WorldWideScience

Sample records for belt conveyors

  1. Belt conveyor for recycle aggregate

    OpenAIRE

    Bezrodný, Roman

    2014-01-01

    This bachelor thesis deals with the belt conveyor for the transport of recycled aggregate in an oblique direction. The aim is to find constructional solutions to the belt conveyor for the assigned transport capacity of 95 000 kg per hour, and the assigned axial distance of 49 m and different height of 12 m. The thesis contains a brief description of the belt conveyor and a description of basic constructional components. It also contains a functional calculation of the capacity and forces acco...

  2. Dynamic characteristics of conveyor belts

    Institute of Scientific and Technical Information of China (English)

    HOU You-fu; MENG Qing-rui

    2008-01-01

    The dynamic characteristics of a belt conveyor are determined to a large extent by the properties of the belt. This paper describes experiments designed to establish the dynamic properties of belting material. The dynamic elastic modulus, viscous damping and theological constants of the belt were measured. Several properties were studied as a function of the tensile loading on the belt. These included longitudinal vibration, the natural vibration frequency in the transverse direction and the response to an impulse excitation. Vibration response was observed under several different excitation frequencies. Most of these properties have not been tested previously under conditions appropriate for the ISO/DP9856 standard. Two types of belt were tested, a steel reinforced belt and a fabric reinforced belt. The test equipment was built to provide data appropriate for designing belt conveyors. It was observed that the stress wave propagation speed increased with tensile load and that tensile load was the main factor influencing longitudinal vibrations.

  3. Chaos on the conveyor belt

    CERN Document Server

    Sándor, Bulcsú; Tél, Tamás; Néda, Zoltán

    2013-01-01

    The dynamics of a spring-block train placed on a moving conveyor belt is investigated both by simple experiments and computer simulations. The first block is connected by spring to an external static point, and due to the dragging effect of the belt the blocks undergo complex stick-slip dynamics. A qualitative agreement with the experimental results can only be achieved by taking into account the spatial inhomogeneity of the friction force on the belt's surface, modeled as noise. As a function of the velocity of the conveyor belt and the noise strength, the system exhibits complex, self-organized critical, sometimes chaotic dynamics and phase transition-like behavior. Noise induced chaos and intermittency is also observed. Simulations suggest that the maximum complexity of the dynamical states is achieved for a relatively small number of blocks, around five.

  4. A Chaos Conveyor Belt

    Science.gov (United States)

    Schmidt, Britney E.

    2013-10-01

    ocean in light of active processes that may form a “chaos conveyor belt” that drives material exchange on Europa.

  5. Computer-aided design of conveyor belts

    Energy Technology Data Exchange (ETDEWEB)

    Karolewski, B.; Pytel, J.

    1984-01-01

    Possibilities are discussed for using mathematical models of belt conveyors for development of computer-aided design of conveyors for coal mining. Examples of optimization tasks and methods for their solution using computerized simulation are analyzed. The analysis is illustrated by an algorithm used to design a starter for the drive system of a belt conveyor. Electromagnetic moment and starting current are used as optimization criteria. A simplified model of a belt conveyor is used. The model consists of an equation of motion with variable braking moment and variable moment of inertia. 3 references.

  6. Design aspects of multiple driven belt conveyors

    NARCIS (Netherlands)

    Nuttall, A.J.G.

    2007-01-01

    Worldwide belt conveyors are used to transport a great variety of bulk solid materials. The desire to carry higher tonnages over longer distances and more diverse routes, while keeping exploitation costs as low as possible, has fuelled many technological advances. An interesting development in the r

  7. Strategy for replacing conveyor belts in complex haulage systems

    Energy Technology Data Exchange (ETDEWEB)

    Gladysiewicz, L.; Jurdziak, L.; Masella, J.

    1986-01-01

    Discusses service life and reliability of conveyor belts used for mine haulage in brown coal surface mining and a method for optimizing belt service life. Based on analysis of operation of 900-1,200 m long belt conveyors in the Konin surface mine, failure rates and factors that influence belt reliability were determined. Effects of joints, length of belt sections and service life of each belt section were analyzed. Formulae for determining the optimum time interval for replacing belt sections on a long belt conveyor were derived. The formulae consider cost of new belt sections, replacement cost and haulage losses associated with possible belt failure caused by excessive belt service life. The optimization procedure has been successfully tested at the Turow surface mine and power plant. 4 refs.

  8. 30 CFR 57.4263 - Underground belt conveyors.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Underground belt conveyors. 57.4263 Section 57... MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Fire Prevention and Control Firefighting Equipment § 57.4263 Underground belt conveyors. Fire protection shall...

  9. LOAD DISTRIBUTION ON DRUMS OF DOUBLE DRIVE BELT CONVEYOR

    Institute of Scientific and Technical Information of China (English)

    薛河; 苏清祖; 马胜利

    1999-01-01

    The double drum drive is widely used on the mine belt conveyor, which are divided the rigid connected double drums and separately driving double drums according to connected method of two drums. Because of the change of real work condition, the load distribution is changed on the two drive drums, which may produce a slippage between a drum and belt. Slippage may intensify the wear of the drum, and sometimes causing the fire of the belt. This restricts the development toward narrow belt, high velocity and large power of belt conveyor. In this paper, the factors affecting the load distribution of two drums of double drum belt conveyor are'systematically analyzed and some computing formulas derived, by these formulas, the actual load distribution onthe two drums of rigid connected or separately driving belt conveyor can be separately calculated. These formulas also can be as the theory base for adjusting the driving force of two drums.

  10. TAKRAF belt conveyors - effective means of transport for bulk materials

    Energy Technology Data Exchange (ETDEWEB)

    Peterman, L.

    1988-11-01

    Presents belt conveyor types produced by TAKRAF, especially those intended for use at surface mines. The FAM works (Transport Equipment) produces belt conveyors 800-1,400 mm wide, with 2.09-5.24 m/s belt velocity, 460-3,750 m/sup 3//h capacity, max. feed distance 2,500 m and (1-5)x55 kW drive power. The drive stations are based on pontoons or caterpillar vehicles while the end-stations are based on pontoons. Charging hoppers have autonomic drives and are mobile on rail. The described conveyors can also be used in power plants. The FAM works produces 650-800 mm wide conveyors for thermal electric power stations. The conveyors are equipped with metal detectors and metal separators.

  11. Research on Dynamic Tension for Belt Conveyor with Constant Force Automatic Take-Up Assembly

    Institute of Scientific and Technical Information of China (English)

    MENG Guo-ying; CHEN Jing-li; LI Yu-jin

    2003-01-01

    The article Provides a dynamic model for belt conveyor. Based on the drive-force of conveyor, take-up tension of take-up assembly, gravity of conveyor belt and material, and friction between belt and idlers, it gives a viscoelastic dynamic equation for conveyor belt. It presents a calculation method of analytic solution to both viscoelastic dynamic equation and geometric dynamic equation when automatic take-up assembly is applied to belt conveyor. The article also makes a study of design method of limiting and eliminating the conveyor belt's elastic vibration.

  12. DEVELOPMENT OF THE TEST METHODS OF THE CONVEYOR BELTS USED IN ENVIRONMENTS ENDANGERED BY EXPLOSION HAZARDS

    Directory of Open Access Journals (Sweden)

    Florin Adrian PĂUN

    2012-05-01

    Full Text Available Conveyor belts are used for a long period of time in the industry branches where potentially explosive atmospheres could occur. Dangerous phenomena which can be in direct connection with the use of conveyor belts are the ones regarding: - sparks influence over the coating layer and/or resistance internal structure of the stopped conveyor belt; - propagation of a flame along the length of a conveyor belt that was exposed to a energy source relative high like a fire or due to blockage of a conveyor belt as a result of the driving mechanism still operating, that generate a local heating of the conveyor belt in contact with the driving drum, rollers or any other heating source generated by friction. Determining the safety parameters characteristic of the conveyor belts by employing test methods allows assessment of the safety level as well as certification of their explosion protection quality when used in environments with explosion danger.

  13. PROPOSALS ON IMPROVING THE EXCAVATION, TRANSPORT AND COAL DEPOSIT, USING THE RUBBER CONVEYOR BELT

    Directory of Open Access Journals (Sweden)

    Nicoleta-Maria MIHUT

    2016-05-01

    Full Text Available In this work we make a study of the improvement methods of quantity of material transported by conveyor belt. Determination of discharge of solids entail establish of the parameters of the conveyor belt. As a result, we determine the belt speed who provide maximum discharge of solids materials.

  14. Single beam optical conveyor belt for chiral particles

    CERN Document Server

    Fernandes, David E

    2016-01-01

    We propose a novel paradigm to selectively manipulate and transport small engineered chiral particles and discriminate different enantiomers using unstructured chiral light. It is theoretically shown that the response of a chiral metamaterial particle may be tailored to enable an optical conveyor belt operation with no optical traps, such that for a fixed incident light helicity and independent of the nanoparticle location, it is either steadily pushed towards the direction of the photon flow or steadily pulled against the photon flow. Our findings create new opportunities for unconventional optical manipulations of tailored nanoparticles and may have applications in sorting racemic mixtures of artificial chiral molecules and in particle delivery.

  15. Colloidal Microworms Propelling via a Cooperative Hydrodynamic Conveyor Belt.

    Science.gov (United States)

    Martinez-Pedrero, Fernando; Ortiz-Ambriz, Antonio; Pagonabarraga, Ignacio; Tierno, Pietro

    2015-09-25

    We study propulsion arising from microscopic colloidal rotors dynamically assembled and driven in a viscous fluid upon application of an elliptically polarized rotating magnetic field. Close to a confining plate, the motion of this self-assembled microscopic worm results from the cooperative flow generated by the spinning particles which act as a hydrodynamic "conveyor belt." Chains of rotors propel faster than individual ones, until reaching a saturation speed at distances where induced-flow additivity vanishes. By combining experiments and theoretical arguments, we elucidate the mechanism of motion and fully characterize the propulsion speed in terms of the field parameters. PMID:26451584

  16. Effective Conveyor Belt Inspection for Improved Mining Productivity

    Energy Technology Data Exchange (ETDEWEB)

    David LaRose

    2006-07-01

    This document details progress on the project ''Effective Conveyor Belt Inspection for Improved Mining Productivity'' during the period from November 15, 2005 to May 14, 2006. Highlights include significant improvements in the accuracy and reliability of computer-vision based vulcanized splice detection, deployment of the vulcanized splice detection algorithms for daily use in two working mines, and successful demonstration of an early prototype of a Smart-Camera based system for on-site mechanical splice detection in coal mine installations.

  17. Nano-optical conveyor belt with waveguide-coupled excitation.

    Science.gov (United States)

    Wang, Guanghui; Ying, Zhoufeng; Ho, Ho-pui; Huang, Ying; Zou, Ningmu; Zhang, Xuping

    2016-02-01

    We propose a plasmonic nano-optical conveyor belt for peristaltic transport of nano-particles. Instead of illumination from the top, waveguide-coupled excitation is used for trapping particles with a higher degree of precision and flexibility. Graded nano-rods with individual dimensions coded to have resonance at specific wavelengths are incorporated along the waveguide in order to produce spatially addressable hot spots. Consequently, by switching the excitation wavelength sequentially, particles can be transported to adjacent optical traps along the waveguide. The feasibility of this design is analyzed using three-dimensional finite-difference time-domain and Maxwell stress tensor methods. Simulation results show that this system is capable of exciting addressable traps and moving particles in a peristaltic fashion with tens of nanometers resolution. It is the first, to the best of our knowledge, report about a nano-optical conveyor belt with waveguide-coupled excitation, which is very important for scalability and on-chip integration. The proposed approach offers a new design direction for integrated waveguide-based optical manipulation devices and its application in large scale lab-on-a-chip integration.

  18. A Parametric Energy Model for Energy Management of Long Belt Conveyors

    Directory of Open Access Journals (Sweden)

    Tebello Mathaba

    2015-12-01

    Full Text Available As electricity prices continue to rise, the increasing need for energy management requires better understanding of models for energy-consuming applications, such as conveyor belts. Conveyor belts are used in a wide range of industries, including power generation, mining and mineral processing. Conveyor technological advances are leading to increasingly long conveyor belts being commissioned. Thus, the energy consumption of each individual belt conveyor unit is becoming increasingly significant. This paper proposes a generic energy model for belt conveyors with long troughed belts. The model has a two-parameter power equation, and it uses a partial differential equation to capture the variable amount of material mass per unit length throughout the belt length. Verification results show that the power consumption calculations of the newly proposed simpler model are consistent with those of a known non-linear model with an error of less than 4%. The online parameter identification set-up of the model is proposed. Simulations indicate that the parameters can be identified successfully from data with up to 15% measurement noise. Results show that the proposed model gives better predictions of the power consumed and material delivered by a long conveyor belt than the steady-state models in the current literature.

  19. Experimental Study of Kinetic Properties of Pyrolysis for Conveyor Belt in Coal Mine

    Institute of Scientific and Technical Information of China (English)

    SONG Zheng-chang

    2005-01-01

    The combustion of conveyor belt is a leading factor of mine fire. In this paper, the pyrolysis properties of ordinary conveyor belt and fire-resistant belt were studied experimentally with thermo-gravimetric analysis and derivative thermo-gravimetric analysis, and the curves of pyrolysis properties were achieved. On this basis, the activation energy and reaction order of pyrolysis were obtained in combination with theoretical analysis, aiming to provide data for further numerical simulation and simulating experiment of mine fire.

  20. An electromyographic and kinematic comparison between an extendable conveyor system and an articulating belt conveyor used for truck loading and unloading tasks.

    Science.gov (United States)

    Lavender, Steven A; Nagavarapu, Shasank; Allread, W Gary

    2017-01-01

    Many retail distribution centers (DCs) manually load and unload boxes into or out of trailers and shipping containers. This study investigated whether an articulating belt conveyor with a height adjustable platform, positioned at the end of an extendable conveyor, significantly reduces shoulder and back muscle loading and the spine kinematics associated with these tasks. Electromyographic and kinematic data were collected from eight volunteer employees as trailers at a shoe DC were unloaded and from nine volunteer employees as trailers at an apparel DC were loaded. Participants in this repeated measures study handled boxes with a conventional powered extendable conveyor system and with the articulating belt conveyor positioned at the end of the extendable conveyor. Bilaterally the normalized activation levels of the erector spinae and anterior deltoid muscles were reduced when loading and unloading boxes with the articulating belt conveyor. Spine movement speeds were also reduced with the articulating conveyor. PMID:27633236

  1. Optimizing the Pipe Diameter of the Pipe Belt Conveyor Based on Discrete Element Method

    Science.gov (United States)

    Guo, Yong-cun; Wang, Shuang; Hu, Kun; Li, De-yong

    2016-03-01

    In order to increase the transport volume of the pipe belt conveyor and reduce lateral pressure of the supporting roller set, this study aims to optimize the pipe diameter of the pipe belt conveyor. A mechanical model of the pipe belt conveyor with six supporting roller sets in the belt bearing section was built based on the infinitesimal method, and the formula for calculating the lateral pressure of each supporting roller was deduced on the basis of reasonable assumption. Simulated analysis was carried out on the operation process of the pipe belt conveyor by using the discrete element method. The result showed that, when the other conditions were certain, as the pipe diameter increased, the average lateral pressure of the supporting roller set increased, with a gradually decreasing increment, which was consistent with the calculated result of the theoretical formula. An optimized pipe diameter under the current conditions was obtained by fitting the curve of the formula for calculating the transport volume of the pipe belt conveyor and its simulation curve. It provided a certain reference value for improving the transport efficiency and prolonging the service life of the pipe belt conveyor.

  2. Mechanism of hydro-viscous soft start of belt conveyor

    Institute of Scientific and Technical Information of China (English)

    MENG Qing-rui; HOU You-fu

    2008-01-01

    The mechanism of a hydro-viscous soft start is of great importance in the design of a hydro-viscous clutch and its control system. To explain the mechanism of a hydro-viscous soft start, the startup process of a belt conveyor was numerically analyzed with the modified Reynolds equation, an energy equation and a temperature-viscosity equation. The effect of temperature and grooves of the friction disk surface on torque transfer and load capacity of the oil film have also been analyzed. The results show that 1) the grooves are the basis of forming dynamic pressure but they may reduce the capacity of torque transfer to a certain extent,2) during the startup process, temperature has little effect on torque transfer and load capacity and the variation in load capacity of the oil film is very small, indicating that it is preferable to use the flow rate as a control object than the pressure of the feed cylinder.The results have been verified by an experiment.

  3. Research on Magnetic Model of Low Resistance Permanent Magnet Pipe Belt Conveyor

    Science.gov (United States)

    Wang, Shuang; Li, De-yong; Guo, Yong-cun

    2016-09-01

    In view of the feasibility of a new type of low resistance permanent magnet pipe belt conveyor, the magnetic properties of the permanent magnet magnetic pipe conveyor belt system are studied. Based on the molecular current hypothesis, the mathematical model of the three dimensional radial magnetic force of permanent magnet pipe conveyor belt was established. The mathematical model of the radial magnetic force was derived, and the influence factors of the radial magnetic force were derived. The finite element simulation of permanent magnet-magnetic pipe conveyor belt magnetic model was carried out, then the magnetic flux density distribution chart under the conditions of different remanence intensity of different permanent magnet and different lengths of the permanent magnets (along the transport direction) were obtained. The simulation results are consistent with the calculation results, which shows that the permanent magnet pipe belt conveyor is feasible. Under certain conditions, the radial magnetic force has nonlinear increase relations with residual magnetism of permanent magnet and the length of the permanent magnet (along the transport direction).

  4. THE INFLUENCE OF INCREASING RELIABILITY OF BELT CONVEYORS UPON THE PRODUCTIVITY OF LIGNITE QUARRIES

    Directory of Open Access Journals (Sweden)

    FLORIN-MIHAI NIȚESCU

    2012-10-01

    Full Text Available At present belt conveyors have an important role in the mines of lignite quarries because they contribute decisively to achieving an optimum production. From this point of view the management of mines should be constantly preoccupied with ensuring, in optimal conditions, the operation of these elements of fixed capital and, if it is necessary they should maintain constant reliability. In this context, this paper has as theme the relation between the reliability of conveyors and the productivity within lignite quarries.

  5. Design of belt conveyor electric control device based on CC-link bus

    Science.gov (United States)

    Chen, Goufen; Zhan, Minhua; Li, Jiehua

    2016-01-01

    In view of problem of the existing coal mine belt conveyor is no field bus communication function, two levels belt conveyor electric control system design is proposed based on field bus. Two-stage belt conveyor electric control system consists of operation platform, PLC control unit, various sensors, alarm device and the water spraying device. The error protection is realized by PLC programming, made use of CC-Link bus technology, the data share and the cooperative control came true between host station and slave station. The real-time monitor was achieved by the touch screen program. Practical application shows that the system can ensure the coalmine production, and improve the automatic level of the coalmine transport equipment.

  6. Dynamics simulation of the belt conveyor possessing feedback loop during starting

    Institute of Scientific and Technical Information of China (English)

    XI Ping-yuan; ZHANG Hai-tao; LIU Jun

    2005-01-01

    Synthesizing the mechanical models of the belt, the driver and the take-up device, the dynamics model was established on the longitudinal vibration of the overall belt conveyor system with finite elemental method, and S-function simulation block of asynchronous motor owing feedback function was built in Matlab/Simulink software, the simulation block indicates that motor rotation speed and its output moment vary with load and time, and the motor is a dynamic feedback system in working process. The state space block was adopted to express model of the belt. Thus it created simulation model of established dynamic model of overall belt conveyor system with Matlab/Simulink software, and simulates the course of starting by properly setting simulation parameters, and processes data for visualization.

  7. Survival of Listeria monocytogenes on a conveyor belt material with or without antimicrobial additives

    NARCIS (Netherlands)

    Chaitiemwong, N.; Hazeleger, W.C.; Beumer, R.R.

    2010-01-01

    Survival of Listeria monocytogenes on a conveyor belt material with or without antimicrobial additives, in the absence or presence of food debris from meat, fish and vegetables and at temperatures of 10, 25 and 37 °C was investigated. The pathogen survived best at 10 °C, and better at 25 °C than at

  8. In Retrospect, Five Year's Splendid Journey of Wind and Rain,Look into the Future, Five Year's Grand Prospect--Shanxi Phoenix Conveyor Belt Co., Ltd.

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ On January 21, 2006, ShanxiPhoenix Conveyor Belt Co.,Ltd. held the 2005 Honor Convention. Those who attended the conference were Mr. Ren Runhou, Board Chairman of Shanxi Phoenix Conveyor Belt Co., Ltd., Board Chairman & General Manager of Shanxi Luan Mining Group, Mr. Shi Wenlin, Director of Shanxi Phoenix Conveyor Belt Co., Ltd.,Vice General Manager of Shanxi Luan Mining Group, Dr. Feng Weimin, General Manager of Shanxi Phoenix Conveyor Belt Co., Ltd. and Mr. Feng Qiang,Administrative General Manager of Shanxi Phoenix Conveyor Belt Co., Ltd.The conference was presided by Vice General Manager Zhu Junhong.

  9. In Retrospect, Five Year's Splendid Journey of Wind and Rain,Look into the Future, Five Year's Grand Prospect--Shanxi Phoenix Conveyor Belt Co., Ltd.

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

      On January 21, 2006, ShanxiPhoenix Conveyor Belt Co.,Ltd. held the 2005 Honor Convention. Those who attended the conference were Mr. Ren Runhou, Board Chairman of Shanxi Phoenix Conveyor Belt Co., Ltd., Board Chairman & General Manager of Shanxi Luan Mining Group, Mr. Shi Wenlin, Director of Shanxi Phoenix Conveyor Belt Co., Ltd.,Vice General Manager of Shanxi Luan Mining Group, Dr. Feng Weimin, General Manager of Shanxi Phoenix Conveyor Belt Co., Ltd. and Mr. Feng Qiang,Administrative General Manager of Shanxi Phoenix Conveyor Belt Co., Ltd.The conference was presided by Vice General Manager Zhu Junhong.……

  10. Singularity Detection of Magnetic Memory Signal of Steel-Cord Conveyor Belt

    Directory of Open Access Journals (Sweden)

    Qiao Tiezhu

    2013-09-01

    Full Text Available Metal magnetic memory technology was an important method for detecting the steel-cord conveyor belt early fault, characteristics of magnetic memory signal extraction is critical for judging of the conveyor belt failure. Generally using of magnetic memory signal maximum gradient value can quickly judge the stress concentration zone, but the magnetic memory signal is susceptible to effected by environmental and noise; In view of the weak and non-stationary characteristics of magnetic memory signal, this paper has proposed the singularity detection method based on wavelet transform modulus maximum for metal magnetic memory signal, the method could exactly judged the stress concentration zone of joints and located the fault points of the steel-cord belt, the characteristic gradient of magnetic memory signal and the Lipschitz exponent were extracted. The result of simulation indicated the technology was effectively for judging the stress concentration zone and fault point. ��

  11. Modeling a magneto-rheological soft starter for use with belt conveyors

    Institute of Scientific and Technical Information of China (English)

    Tian Zuzhi; Hou Youfu

    2012-01-01

    The theory of magnetic circuit design,the constitutive equations of a magneto-rheological fluid,and the load properties of belt conveyors were used to design a magneto-rheological soft starter test-bed.The magnetic field distribution in the working gap was analyzed and the current-speed relationship was investigated.A mathematical model for the time response was deduced.The results show that a linear relationship between current and magnetic field is seen when the magnetic materials are not saturated and the magnetic field is uniform in the working section.The rotation speed of the driven shaft changes linearly with increasing time.The response is rapid and can be as short as milliseconds.This meets the starting requirements of belt conveyors.

  12. Reinforcing materials in conveyor belts: their requirements and developments; Verstaerkungsmaterialien in Foerdergurten: Tendenzen, Anforderungen und Entwicklungen

    Energy Technology Data Exchange (ETDEWEB)

    Kopmels, P. [Akzo Nobel Fibers, Arnhem (Netherlands)

    1994-12-31

    During this century one can observe a gradual change in the textile materials used to reinforce conveyor belt. In the beginning of the 20th century only cotton was used, then rayon came up followed by polyamide and polyester. Nowadays aramid is also used for special applications. These changes in textile reinforcing materials were driven by a better fulfilment of the existing technical requirements and/or a better price/performance ratio. In addition to the search for new polymers, the fiber producers try to improve the yarn properties of existing polymers. An example of a newly developed polyester type is presented. By raising the yarn strength and at the same time improving the efficiency of the yarn in respect to the necessary converting steps like twisting, weaving and dipping the price/performance ratio of this new yarn type has been greatly improved. 11 figs.

  13. Release measurement of great amount of waste. Conveyor belt versus wire mesh pallet systems

    Energy Technology Data Exchange (ETDEWEB)

    Sokcic-Kostic, Marina; Schultheis, Roland; Langer, Felix [NUKEM Technologies Engineering Services GmbH, Alzenau (Germany)

    2014-08-15

    Great amount of waste has to be measured for release during the decommissioning and rebuilding of nuclear facilities and installation. Since the enclosed storage or decontamination is very expensive it is advisable for economic reasons to separate contaminated material. The necessary measurement is however a time and cost intensive work which has carefully provided. There are two general methods to perform this task: one is a continuously running system on the basis of a conveyor belt system. The other approach is a discontinuously running system using wire mesh pallets. With the knowledge from existing installations this article will discuss the pro's and contra's and show the limits of the systems.

  14. The conveyor belt hypothesis for thymocyte migration: participation of adhesion and de-adhesion molecules

    Directory of Open Access Journals (Sweden)

    Villa-Verde D.M.S.

    1999-01-01

    Full Text Available Thymocyte differentiation is the process by which bone marrow-derived precursors enter the thymus, proliferate, rearrange the genes and express the corresponding T cell receptors, and undergo positive and/or negative selection, ultimately yielding mature T cells that will represent the so-called T cell repertoire. This process occurs in the context of cell migration, whose cellular and molecular basis is still poorly understood. Kinetic studies favor the idea that these cells leave the organ in an ordered pattern, as if they were moving on a conveyor belt. We have recently proposed that extracellular matrix glycoproteins, such as fibronectin, laminin and type IV collagen, among others, produced by non-lymphoid cells both in the cortex and in the medulla, would constitute a macromolecular arrangement allowing differentiating thymocytes to migrate. Here we discuss the participation of both molecules with adhesive and de-adhesive properties in the intrathymic T cell migration. Functional experiments demonstrated that galectin-3, a soluble ß-galactoside-binding lectin secreted by thymic microenvironmental cells, is a likely candidate for de-adhesion proteins by decreasing thymocyte interaction with the thymic microenvironment.

  15. ANALYSIS OF MOVEMENT RESISTANCE OF CONVEYOR BELT AND ROLLERS IN THE COAL MINE MYSŁOWICE-WESOŁA

    Directory of Open Access Journals (Sweden)

    Tadeusz OPASIAK

    2014-03-01

    Full Text Available The paper presents a study of new design of SAG rollers. The study focused on the measurement of static and dynamic resistance of rotating rollers and the impact of new construction on the power consumption of the conveyor. Rollers have been modified through the use of class C4 bearing seals and labyrinth seal U4Exp 62/65 with a cover 2LU4 of runner construction. Measurements of static and dynamic resistance of rotating rollers were made on a universal rollers test bench, and power measurements were carried out on a belt conveyor power supply system Gwarek 1200 No. TW in KWK Mysłowice-Wesoła

  16. The interaction between warm conveyor belts and breaking Rossby waves: a climatological perspective.

    Science.gov (United States)

    Madonna, Erica; Joos, Hanna; Martius, Olivia; Aebi, Christine; Limbach, Sebastian

    2014-05-01

    Warm conveyor belts (WCBs) are moist ascending airstreams in extratropical cyclones. Climatologically, they are key for the meridional and vertical transport of water vapour and heat. The rapid ascent of WCBs from the boundary layer to the upper troposphere in about 1-2 days leads to cloud formation, (intense) precipitation and the release of latent heat, which modifies their potential vorticity (PV) value in a significant way. Typically WCBs reach the tropopause level with low PV values (~0.5 pvu) and therefore the cross-isentropic transport of low-PV air in WCBs can amplify upper-level Rossby waves and contribute to the formation of PV streamers downstream. Here, filamentary PV streamers are regarded as clear signs of breaking Rossby waves. They in turn can act as precursors of extreme weather events and/or trigger the genesis of another cyclone, potentially generating a new WCB. The aim of this study is to quantify the interaction of WCBs and PV-streamers from a climatological point of view for the ERA-Interim data set for the period 1989-2010. WCBs are identified from comprehensive trajectory calculations that select air parcels in the vicinity of cyclones with a minimum ascent of 600 hPa in 48 hours. From these WCB trajectories, coherent features of WCB outflows are derived and checked for overlapping with PV streamers, which are identified using a contour searching algorithm. Both, WCBs and PV-streamers are then tracked using a novel feature tracking technique, which is based upon a modified region growing approach. With this technique, the interaction of WCBs and PV-streamers is analysed for a 22-years period leading to novel insight about the role of WCBs for triggering the breaking of Rossby waves, as well as, vice versa, about the importance of PV-streamers for the formation of new WCBs.

  17. A mathematical model and simulation of the drying process of thin layers of potatoes in a conveyor-belt dryer

    Directory of Open Access Journals (Sweden)

    Salemović Duško R.

    2015-01-01

    Full Text Available This paper presents a mathematical model and numerical analysis of the convective drying process of small particles of potatoes slowly moving through the flow of a drying agent - hot moist air. The drying process was analyzed in the form of a one-dimensional thin layer. The mathematical model of the drying process is a system of two ordinary nonlinear differential equations with constant coefficients and an equation with a transcendent character. The appropriate boundary conditions of the mathematical model were given. The presented model is suitable in the automated control. The presented system of differential equations was solved numerically. The analysis presented here and the obtained results could be useful in predicting the drying kinetics of potatoes and similar natural products in a conveyor-belt dryer. [Projekat Ministarstva nauke Republike, br. TR-33049, br. TR-37002 i br. TR-37008

  18. STUDY ON THE CONTROL SYSTEM OF HYDRAULIC MOMENT-ADJUSTED BRAKE FOR DOWNWARD BELT CONVEYOR

    Institute of Scientific and Technical Information of China (English)

    孟国营; 徐志强; 霍森; 方佳雨

    1997-01-01

    Having analyzed the drawbacks on the design of control system of hydraulic momentadjusted brake system, the author presents a closed loop control system in the process of start and braking of the conveyer. On the basis of the concept of the critical time and the critical acceleration and its deductions, the working mode of the conveyer can be identified and controlled in feedback, furthermore, thus realize the process of soft start. In the deceleration process, the author points out the problems that exist in the present control system and sets forward the control process that acted by the combined function of brake moment of motor and the drag torque of hydraulic brake at the beginning of deceleration, it will further improved reliability of conveyor system.

  19. 摩擦阻尼式下运带式输送机的开发与应用%Exploitation and application of friction damp downward belt conveyor

    Institute of Scientific and Technical Information of China (English)

    张玉国; 熊作银; 李秀云; 丁立伟

    2001-01-01

    通过技术和经济分析,说明摒弃传统制动方法而使用摩擦阻尼式下运带式输送机的可行性。%Based on analysis of technology and commercial efficienly,this article introduces the practicability of adopting friction damp downward belt conveyor by way of abandoning traditional way of braking.

  20. New Conveyor Belt Lubrication Self-cleaning System%新型输送带润滑自清洁系统

    Institute of Scientific and Technical Information of China (English)

    王海兵; 许斌; 刘凤臣; 叶鹏

    2011-01-01

    In various types of beverage production line, conveyor belt plays an essential role. In order to prevent the bottle inverting, reducing wear, conveyor belt need to be lubricated. Lubrication by spraying is commonly used, but it exists kinds of problems such as non-uniform, waste, unfriendly-environment, breeding bacteria, scaling, and plugin noggle easily, difficult to clean and so on. Through comparative analysis, the paper proposed a new conveyor belt lubrication selfcleaning system with several advantages such as cycling lubrication, cleanness and asepsis, friendly environment conservation and maintenance fiee.[Ch,5 fig.1 tab.9 ref.]%在各类饮料生产线中,输送带起着不可或缺的作用.为了防止倒瓶、减少输送带自身的磨损,需对输送带进行润滑.通常采用的传统喷洒式润滑方法,在实际使用中存在润滑不均匀、浪费大、不环保、易长菌、易结垢、难清洁、喷嘴易堵塞等问题.通过对比分析,研制出一种新型的输送带滑润自清洁系统,具有循环润滑、清洁无菌、节约环保、免维护的优点.

  1. Occupational exposure to rubber vulcanization products during repair of rubber conveyor belts in a brown coal mine.

    Science.gov (United States)

    Gromiec, Jan P; Wesołowski, Wiktor; Brzeźnicki, Sławomir; Wróblewska-Jakubowska, Krystyna; Kucharska, Małgorzata

    2002-12-01

    Several hundred chemical compounds were found in workroom environments in the rubber industry, but most of the published exposure data relate to the production of tyres; information from the "non-tyre" sections are very limited, if any. This study was carried out to identify chemical substances and measure their air concentrations in the repair shop of a brown coal mine in which damaged rubber conveyor belts were repaired. GC-MS and HPLC analysis of stationary air samples resulted in identification of aliphatic and aromatic hydrocarbons to C12, PAHs, alcohols, phenols, ketones, heterocyclic nitrogen and sulfur compounds. Quantitative evaluation of occupational exposure included determination of organic compound vapours collected on charcoal (GC-MSD), polycyclic aromatic hydrocarbons (HPLC), N-nitrosoamines and other amines (GC-NPD) and DNPH derivatives of aldehydes (HPLC) in the breathing zone of workers representing all job titles. The concentrations of investigated compounds were very low. Carcinogenic substances: N-nitrosoamines, benzene, PAHs were not present in workroom air in concentrations exceeding limits of detection of the analytical methods being applied; concentrations of methylisobutylketone, tetrachloroethylene, naphtha, aromatic hydrocarbons, phthalates and aldehydes were much lower than the respective occupational exposure limit values. The results indicate much lower exposure than that reported in the production of tyres and other fabricated rubber products. PMID:12509065

  2. Standardized components for belt conveyor drives - a design to cost concept; Standardkomponenten fuer Gurtfoerderantriebe - ein kostenguenstiges Konzept

    Energy Technology Data Exchange (ETDEWEB)

    Raphael, E. [A. Friedr. Flender AG, Bocholt (Germany)

    1997-11-01

    The technical progress in material and manufacture allowed an enormous size reduction of mechanical belt drives during the 70s and 80s of this century. Further cost reduction with no change in product quality were achieved by a standardized drive component concept providing all features needed for conveyor drives. There are a lot of details that need to be discussed. To be consequent, service factors of gearing, service life of bearings and thermal stability of the drive have to be redefined. Standardized seal systems help to prevent oil leakages and damages from environmental dust. Examples show that this concept is reliable in heavy duty service conditions of mining applications. (orig.) [Deutsch] Im Bereich der mechanischen Antriebe von Gurtfoerderern haben sich im Verlauf des letzten Jahrzehnts erhebliche technische oder logistische Veraenderungen vollzogen, die die Anschaffungs- und Betriebskosten der Antriebe senken helfen. Nach technischen Quantenspruengen in den Jahren 1970-1990 sind in diesem Jahrzehnt Systeme standardisierter Antriebskomponenten entstanden, welche fuer nahezu alle denkbaren Faelle die bedarfsgerechte Auswahl eines Gurtfoerdererantriebes gestatten. (orig.)

  3. Improvement on the Belt Conveyor of the Coal Mine%浅谈煤矿胶带运输机的改造

    Institute of Scientific and Technical Information of China (English)

    李文光

    2015-01-01

    针对目前煤矿井下特殊环境的要求,对胶带运输机机械的防腐、运输、安装及安全制动问题做了表述。改变了胶带输送机的安装方式,在传动滚筒与卸载滚筒或改向滚筒各安装1台逆止器,改造后的胶带输送机能正常制动、紧急制动,大大提高了输送机的安全可靠与稳定性;同时对多驱动变频电气系统进行了改造,解决了多驱动变频装置同步平衡问题,现场使用效果很好。%Aiming at the requirement of special environment of underground coal mine ,belt conveyor machinery ,transport ,install anti‐cor‐rosion and safe braking problems made statements .Change the installation mode of belt conveyor ,the driving drum and drum or drum to un‐load the installation of 1 sets of backstop ,belt conveyor after transformation can normal braking ,emergency braking ,greatly improves the safety and stability of the conveyor ;at the same time of multi drive variable frequency electric and gas system are modified ,solve the multi drive frequency conversion device of synchronous balance problems ,field use effect is very good .

  4. PLC在胶带输送机上的应用%The Application of PLC on Belt Conveyor

    Institute of Scientific and Technical Information of China (English)

    刘青菊

    2011-01-01

    通过RLC控制系统和PLC可编程控制器的对比,选用可编程序(PLC)控制系统对胶带输送机的电气控制系统进行设计改造,为生产设备集中控制打下基础。本控制系统选用西门子PLC作为控制器,在设计硬件电路中,对PLC及外部低压电器进行选型,设计了硬件接线图并对控制系统提出要求,使之具有控制和保护功能。在软件设计中,给出了程序流程图与梯形图,将硬件和软件有机结合,保证控制系统可靠运行,达到了生产工序要求。%Through the comparison between RLC control system and PLC programmable controller,programmable logic control system(PLC) is used for the electrical control system reform of belt conveyor,to prepare for the centralized control of production equipment.The Siemens PLC control system is used as the controller.In the design of hardware circuit,the selection of proper PLC and external low-voltage electrical appliances is conducted.The hardware wiring diagram is designed and requirement for control system is put forward so that it has control and protection functions.In software design,the program flow chart and ladder diagram is presented,to combine hardware and software to ensure reliable operation of the control system to achieve the production process requirements.

  5. Conveyor belt clock synchronization

    CERN Document Server

    Giovannetti, V; Maccone, L; Shapiro, J H; Wong, F N C; Giovannetti, Vittorio; Lloyd, Seth; Maccone, Lorenzo; Shapiro, Jeffrey H.; Wong, Franco N. C.

    2004-01-01

    A protocol for synchronizing distant clocks is proposed that does not rely on the arrival times of the signals which are exchanged, and an optical implementation based on coherent-state pulses is described. This protocol is not limited by any dispersion that may be present in the propagation medium through which the light signals are exchanged. Possible improvements deriving from the use of quantum-mechanical effects are also addressed.

  6. Modeling and Simulating Research of AMT Driving Belt Conveyor%AMT驱动带式输送机的建模与仿真

    Institute of Scientific and Technical Information of China (English)

    刘春辉; 关志伟; 孟亚东; 周毅

    2011-01-01

    The belt conveyor is the most important translation equipment which can carry categories of materials, but its drive system is expensive, complex and difficult to maintain. Automatic mechanical transmission takes an im-portant role in Automatic Transmission, due to its high transfer efficiency, low cost, easy to manufacture and conven-ient to maintain. Based on this, a program of belt conveyor cranking up is firstly put forward. In this program, three - phase asynchronous motor produces power, AMT transmits power, and ECU controls automatic shifting. The thesis employs the simulation software Matlab/Simulink to build a simulation model for AMT driving belt conveyor. The simulation results show that the maximum acceleration of belt meets requirements. In small power and low velocity occasion, the AMT of five gears is feasible.%研究带式输送机优化速度特性,针对带式输送机驱动装置效率低、物料运量不可变、造价高的问题,根据电控机械式自动变速器传动效率高、实现有级调速、成本低.为了提高系统的传动效率,改进驱动装置,提出一种以AMT作为传动系统,通过电子控制单元的操作实现自动驱动带式输送机进行起动的方案.分析方案的可行性,建立了AMT和带式输送机的动力学模型.利用Matlab工具,建立了AMT驱动带式输送机的仿真模型,并对起动过程进行仿真.仿真结果表明,使输送带的最大加速度和速度满足要求,且方案能保证离合器的优化特性,提高了传动效率,的确为方案的实现提供了理论支持.

  7. Real - time Detection Technology for Prevention of Conveyor Belt Ripstop%带式输送机防撕裂实时检测技术研究

    Institute of Scientific and Technical Information of China (English)

    苏畅; 王从东

    2012-01-01

    Existing domestic real - time detection technology of conveyor belt ripstop is not only expensive but also environmental adaptability. The causes of convzyor belt ripping accidents and the application of ripstop monitoring technology were analyzed. Based on the wireless information transmission with zigbee technology, a new real - time detection method was proposed with improvement of belt' s structure. Convayor belt working status can be determined by detection of pressure change in air bag of the belt. The results showed that the new method is effective in detection and protection from the accidents by immediate alarming and braking, when belt being punctured , ripped or braken.%由于国内现有带式输送机防撕裂实时检测技术不但价格昂贵而且环境适应性差,通过对带式输送机输送带发生撕裂事故原因及现有防撕裂实时监控技术的应用情况分析,基于zigbee技术进行无线信息传输,通过对输送带结构改进,提出一套新的实时检测方案.利用检测输送带气囊内压力变化,判断输送带工作情况是否正常.结果表明:当发生刺穿、撕裂或断裂时立刻报警并制动,能起到有效的检测和保护作用.

  8. 煤炭输送带表面对煤粉的仿生脱附研究%Bionic Anti-adhesive Study Between the Coal Conveyor Belt Surface and the Coal

    Institute of Scientific and Technical Information of China (English)

    李晶; 徐成宇; 曾丽娜

    2013-01-01

    分析了煤炭带式输送机输送带表面与煤粉粘附现象,从生物体表自洁现象中得到启示,利用生物仿生学原理,提出改善输送带表面形貌以达到与煤粉脱附的目的.以荷叶表面结构形貌为原型,分析其微观结构形貌,运用相似工程学原理设计出一种具有凸包结构的输送带表面形貌,以达到有效脱附煤粉,并建立该结构的实体模型.%With analysis of the phenomenon that coal fines adsorb to the belt surface on coal conveyor,a new idea focused on improvement in the surface topography of conveyor belt to decrease adhesion of coal fines is presented on the basis of inspiration from the biological self-cleaning phenomenon and perspective of bionics.The surface topography with papillary structure of conveyor belt surface is designed on the basis of Lotus-leaf-likes surface with analysis of its microstructure in accordance with similarity principle.The new structure could effectively prevent coal fines from adhering to conveyor belt surface.A model of the new structure is also built.

  9. The Green Design of the Belt Conveyor for Cement Industry%浅谈水泥工业用带式输送机的绿色设计

    Institute of Scientific and Technical Information of China (English)

    黄兰

    2015-01-01

    带式输送机广泛应用于水泥工业的多个环节,在转运和输送粉粒状物料的过程中,易产生扬尘和洒落,造成粉尘污染。为了有效降低粉尘污染,引入绿色设计理念,介绍相关粉尘控制的绿色设计方法、技术和措施,实现带式输送机的清洁运输。%Belt conveyor is widely used in cement industry .When transferring the powdery or particulate material ,dust pollution is caused by the fugitive dust .In order to reduce dust pollution ,introducing the concept of green design ,including green design methods ,techniques and measures for dust control .

  10. 浅谈水泥工业用带式输送机的绿色设计%The Green Design of the Belt Conveyor for Cement Industry

    Institute of Scientific and Technical Information of China (English)

    黄兰

    2015-01-01

    带式输送机广泛应用于水泥工业的多个环节,在转运和输送粉粒状物料的过程中,易产生扬尘和洒落,造成粉尘污染。为了有效降低粉尘污染,引入绿色设计理念,介绍相关粉尘控制的绿色设计方法、技术和措施,实现带式输送机的清洁运输。%Belt conveyor is widely used in cement industry .When transferring the powdery or particulate material ,dust pollution is caused by the fugitive dust .In order to reduce dust pollution ,introducing the concept of green design ,including green design methods ,techniques and measures for dust control .

  11. A case study on the formation and evolution of ice supersaturation in the vicinity of a warm conveyor belt's outflow region

    Directory of Open Access Journals (Sweden)

    P. Spichtinger

    2005-01-01

    Full Text Available A case study is presented on the formation and evolution of an ice-supersaturated region (ISSR that was detected by a radiosonde in NE Germany at 06:00 UTC 29 November 2000. The ISSR was situated in the vicinity of the outflow region of a warm conveyor belt associated with an intense event of cyclogenesis in the eastern North Atlantic. Using ECMWF analyses and trajectory calculations it is determined when the air parcels became supersaturated and later subsaturated again. In the case considered, the state of air parcel supersaturation can last for longer than 24h. The ISSR was unusually thick: while the mean vertical extension of ISSRs in NE Germany is about 500m, the one investigated here reached 3km. The ice-supersaturated region investigated was bordered both vertically and horizontally by strongly subsaturated air. Near the path of the radiosonde the ISSR was probably cloud free, as inferred from METEOSAT infrared images. However, at other locations within the ISSR it is probable that there were cirrus clouds. Relative humidity measurements obtained by the Lindenberg radiosonde are used to correct the negative bias of the ECMWF humidity and to construct two-dimensional maps of ice supersaturation over Europe during the considered period. A systematic backward trajectory analysis for the ISSRs on these maps shows that the ISSR air masses themselves experienced only a moderate upward motion during the previous days, whereas parts of the ISSRs were located just above strongly ascending air masses from the boundary layer. This indicates qualitatively that warm conveyor belts associated with mid-latitude cyclogenesis are disturbances that can induce the formation of ISSRs in the upper troposphere. The ISSR maps also lead us to a new perception of ISSRs as large dynamic regions of supersaturated air where cirrus clouds can be embedded at some locations while there is clear air at others.

  12. Combined steam-ultrasound treatment of 2 seconds achieves significant high aerobic count and Enterobacteriaceae reduction on naturally contaminated food boxes, crates, conveyor belts, and meat knives.

    Science.gov (United States)

    Musavian, Hanieh S; Butt, Tariq M; Larsen, Annette Baltzer; Krebs, Niels

    2015-02-01

    Food contact surfaces require rigorous sanitation procedures for decontamination, although these methods very often fail to efficiently clean and disinfect surfaces that are visibly contaminated with food residues and possible biofilms. In this study, the results of a short treatment (1 to 2 s) of combined steam (95°C) and ultrasound (SonoSteam) of industrial fish and meat transportation boxes and live-chicken transportation crates naturally contaminated with food and fecal residues were investigated. Aerobic counts of 5.0 to 6.0 log CFU/24 cm(2) and an Enterobacteriaceae spp. level of 2.0 CFU/24 cm(2) were found on the surfaces prior to the treatment. After 1 s of treatment, the aerobic counts were significantly (P plastic modular conveyor belts with hinge pins and one type of flat flexible rubber belt, all visibly contaminated with food residues. The aerobic counts of 3.0 to 5.0 CFU/50 cm(2) were significantly (P effective replacement for disinfection processes and that it can be used for continuous disinfection at fast process lines. However, the treatment may not be able to replace efficient cleaning processes used to remove high loads of debris. PMID:25710163

  13. Spraying Dust-settling Technology of Belt Conveyor Transfer Point with Conical Hollow Nozzle%带式输送机转载点锥形空心喷嘴喷雾降尘技术

    Institute of Scientific and Technical Information of China (English)

    陈颖兴

    2012-01-01

    根据带式输送机转载点产尘特点,设计出低水压、低耗水、高雾化且适宜带式输送机转载点喷雾降尘的锥形空心喷嘴,并在实验室验证了其在低压力、低耗水情况下的雾化效果。通过在山西国阳新能公司一矿带式运输转载点现场试验和应用,证明锥形空心喷雾降尘技术能有效地治理转载点的粉尘污染。%According to the dust generation features of belt conveyor transfer point,a kind of conical hollow nozzle with low water pressure,less water and high atomization was designed which is suitable for the transfer point spraying dust-settling of belt conveyer.The atomization effect was verified in lab under the condition of low water pressure and less water.Through the on-site test and application with belt conveyor transfer point in No.1 mine of Shanxi Guoyang new energy company,the technology of spraying dust-settling with conical hollow nozzle can effectively solve the dust pollution of belt conveyor transshipment point.

  14. Design of Belt Conveyor Control System Based on PLC SIEMENS S7-200%基于PLC西门子S7-200的带式输送机控制系统设计

    Institute of Scientific and Technical Information of China (English)

    李博

    2015-01-01

    Belt conveyor is a conveyor belt driven by the driving roller, as a continuous conveying equipment, which is one of the main transport equipment in modern mines. In particular, the modern large-scale coal mines, coal transportation is mainly through the conveyor to complete. Conveyor is characterized by large transmission capacity, small power consumption, simple structure, strong adaptability to the material, easy to form water production line, so that the enterprise production process to achieve mechanization. Belt conveyor in coal mine and coal preparation plant plays a important role, under the background of enterprise development of coal mining mechanization, automation, automatic control operation of the conveyor belt is particularly important. In this paper, the design and programming of the conveyor system are carried out with the SIEMENS S7-200 programmable controller as an example.%带式输送机是一种由驱动滚筒带动的输送带,作为一种连续输送的设备,其是现代矿井的主要运输设备之一.尤其是现代化大型的煤矿,煤的运输主要通过输送机来完成.输送机的特点是输送能力大,功耗小,构造简单,对物料的适应性强,便于组成流水生产线,使企业生产过程实现机械化.带式输送机在煤矿及洗煤厂发挥着重要作用,在企业发展采煤机械化、自动化的背景下,带式输送机的自动控制运行显得尤为重要.本文以西门子S7-200可编控制器为例进行输送机系统的编程和设计.

  15. DSJ100/100/3×200型顺槽带式输送机的研制%Development of DSJ1 00/1 00/3 ×200 Type Belt Conveyor

    Institute of Scientific and Technical Information of China (English)

    赵世旭

    2014-01-01

    Aiming at the transportation requirements of special roadway and universality of series product in Xis-han coal and electricity (group)company,on the basis of digestion and absorption the experience of traditional belt conveyor,through optimization design of the existing DSJ100 series tunnel extensible belt conveyor in Xishan coal and electricity group electromechanical factory,a new kind of belt conveyor is developed,which is safe,reliable and en-ergy saving.Introduces through adopting the key techniques such as variable frequency conversion start mode,the new integral base,unloading intermediate drive,the fast disassembly fuselage and so on,adaptability,safety reliabili-ty and economy of belt conveyor to severe environment in the underground of coal mine is improved effectively.%针对西山煤电(集团)公司矿井特殊巷道运输要求和产品系列的通用性,在消化和吸收传统顺槽带式输送机经验的基础上,对西山机电厂现有DSJ100系列顺槽可伸缩带式输送机进行了优化设计,研制开发出了一种安全、可靠、节能的新型带式输送机。介绍了通过采用变频调速启动方式、新式整体底座、卸载式中间驱动、快速可拆卸机身等关键技术,有效提高了带式输送机对煤矿井下恶劣环境的适应能力、安全可靠性及经济性。

  16. Application of PLC Centralized Control System of Coal Mine Belt Conveyor%PLC集中控制系统在煤矿胶带输送机上的应用

    Institute of Scientific and Technical Information of China (English)

    秦永康; 黄和平

    2011-01-01

    针对某矿胶带运输系统线路长、岗位多、联络环节多的特点,提出了一种采用PLC集中控制系统控制煤矿胶带输送机的方案,介绍了PLC集中控制系统的构成、工作原理和系统功能.该系统通过集中控制和工业电视相结合,对井下主煤流强力胶带输送机和振动给煤机及煤仓煤位计等相关设施进行监测,实现了主煤流系统的集中控制.实际应用表明,该系统运行良好,实现了胶带输送机的安全高效运行.%In view of characteristics of long lines, multi posts and multi links of transport system of belt converyor of a mine, the paper proposed a scheme which adopts PLC centralized control system to control coal mine belt conveyor.It introduced composition, working principle and functions of PLC centralized control system.The system combines industrial television with centralized control to monitor related devices such as underground powerful belt conveyor, vibration coal feeder and coal level sensor of coal bunker, which realizes centralized control of main coal flow system.The practical application showed that the system runs well, and achieves safe and efficient running of conveyor belt.

  17. Current methods and possibilities to determine the variability of Cu content in the copper ore on a conveyor belt in one of KGHM Polska Miedz S.A. mines

    Directory of Open Access Journals (Sweden)

    Jurdziak Leszek

    2016-01-01

    Full Text Available In this paper the methodology of ore sampling on a belt conveyor in one of KGHM Polska Miedz S.A. mines was presented together with the results of analysis of the variation of ore tonnage and quality. The ore was transferred from one mine to another one through the analysed transfer conveyor on the route from the mine Division of Mining to copper plants. The transported ore was sampled in person from Division of Concentrators on a regular basis for metal accounting purposes between both mines. The ore quality control became a significant problem since it is impossible to predict with satisfactory advance both Cu content in the feed as well as its lithology composition which is required to improve and optimise the enrichment efficiency.

  18. Solvent minimization induces preferential orientation and crystal clustering in serial micro-crystallography on micro-meshes, in situ plates and on a movable crystal conveyor belt.

    Science.gov (United States)

    Soares, Alexei S; Mullen, Jeffrey D; Parekh, Ruchi M; McCarthy, Grace S; Roessler, Christian G; Jackimowicz, Rick; Skinner, John M; Orville, Allen M; Allaire, Marc; Sweet, Robert M

    2014-11-01

    X-ray diffraction data were obtained at the National Synchrotron Light Source from insulin and lysozyme crystals that were densely deposited on three types of surfaces suitable for serial micro-crystallography: MiTeGen MicroMeshes™, Greiner Bio-One Ltd in situ micro-plates, and a moving kapton crystal conveyor belt that is used to deliver crystals directly into the X-ray beam. 6° wedges of data were taken from ∼100 crystals mounted on each material, and these individual data sets were merged to form nine complete data sets (six from insulin crystals and three from lysozyme crystals). Insulin crystals have a parallelepiped habit with an extended flat face that preferentially aligned with the mounting surfaces, impacting the data collection strategy and the design of the serial crystallography apparatus. Lysozyme crystals had a cuboidal habit and showed no preferential orientation. Preferential orientation occluded regions of reciprocal space when the X-ray beam was incident normal to the data-collection medium surface, requiring a second pass of data collection with the apparatus inclined away from the orthogonal. In addition, crystals measuring less than 20 µm were observed to clump together into clusters of crystals. Clustering required that the X-ray beam be adjusted to match the crystal size to prevent overlapping diffraction patterns. No additional problems were encountered with the serial crystallography strategy of combining small randomly oriented wedges of data from a large number of specimens. High-quality data able to support a realistic molecular replacement solution were readily obtained from both crystal types using all three serial crystallography strategies.

  19. 永磁直驱皮带机系统关键技术的研究%Key Technology of Permanent-magnet Direct Drive Belt Conveyor System

    Institute of Scientific and Technical Information of China (English)

    许赟莉; 朱殿瑞

    2014-01-01

    For solving the problems in the traditional belt conveyor drive system such as low efficiency , unsteady startup , a permanent-magnet direct drive system is developed ,to achieve the purpose of high efficiency ,energy-saving ,stable startup .The permanent-magnet direct drive system using gearless permanent-magnet synchronous frequency conversion drive system composed of a permanent magnet synchronous motor and a frequency converter can realize the power transmission .Without the gear reducer and hydraulic coupler ,the entire drive system is of the advantages of low noise ,no maintenance ,large output torque ,stable starting , constant torque control and so on .%为了改变带式输送机传统驱动系统效率低、启动不平稳、重载启动困难等缺点,达到高效、节能、启动平稳、恒转矩控制的目的,永磁直驱系统采用了无齿轮永磁同步变频直驱系统,即驱动系统由永磁同步电机与变频器相结合实现动力的传递。由于去掉了减速器、液力耦合器,因此整个驱动系统具有低噪声、免维护、输出转矩大、启动平稳、恒转矩控制等优点。

  20. Solvent minimization induces preferential orientation and crystal clustering in serial micro-crystallography on micro-meshes, in situ plates and on a movable crystal conveyor belt

    International Nuclear Information System (INIS)

    Strategies are described for optimizing the signal-to-noise of diffraction data, and for combining data from multiple crystals. One challenge that must be overcome is the non-random orientation of crystals with respect to one another and with respect to the surface that supports them. X-ray diffraction data were obtained at the National Synchrotron Light Source from insulin and lysozyme crystals that were densely deposited on three types of surfaces suitable for serial micro-crystallography: MiTeGen MicroMeshes™, Greiner Bio-One Ltd in situ micro-plates, and a moving kapton crystal conveyor belt that is used to deliver crystals directly into the X-ray beam. 6° wedges of data were taken from ∼100 crystals mounted on each material, and these individual data sets were merged to form nine complete data sets (six from insulin crystals and three from lysozyme crystals). Insulin crystals have a parallelepiped habit with an extended flat face that preferentially aligned with the mounting surfaces, impacting the data collection strategy and the design of the serial crystallography apparatus. Lysozyme crystals had a cuboidal habit and showed no preferential orientation. Preferential orientation occluded regions of reciprocal space when the X-ray beam was incident normal to the data-collection medium surface, requiring a second pass of data collection with the apparatus inclined away from the orthogonal. In addition, crystals measuring less than 20 µm were observed to clump together into clusters of crystals. Clustering required that the X-ray beam be adjusted to match the crystal size to prevent overlapping diffraction patterns. No additional problems were encountered with the serial crystallography strategy of combining small randomly oriented wedges of data from a large number of specimens. High-quality data able to support a realistic molecular replacement solution were readily obtained from both crystal types using all three serial crystallography strategies

  1. Solvent minimization induces preferential orientation and crystal clustering in serial micro-crystallography on micro-meshes, in situ plates and on a movable crystal conveyor belt

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Alexei S., E-mail: soares@bnl.gov [Brookhaven National Laboratory, Upton, NY 11973 (United States); Mullen, Jeffrey D. [Brookhaven National Laboratory, Upton, NY 11973 (United States); University of Oregon, Eugene, OR 97403-1274 (United States); Parekh, Ruchi M. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Suffolk County Community College, Selden, NY 11784 (United States); McCarthy, Grace S.; Roessler, Christian G.; Jackimowicz, Rick; Skinner, John M. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Orville, Allen M. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Brookhaven National Laboratory, Upton, NY 11973 (United States); Allaire, Marc [Brookhaven National Laboratory, Upton, NY 11973 (United States); Sweet, Robert M. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Brookhaven National Laboratory, Upton, NY 11973 (United States)

    2014-10-09

    Strategies are described for optimizing the signal-to-noise of diffraction data, and for combining data from multiple crystals. One challenge that must be overcome is the non-random orientation of crystals with respect to one another and with respect to the surface that supports them. X-ray diffraction data were obtained at the National Synchrotron Light Source from insulin and lysozyme crystals that were densely deposited on three types of surfaces suitable for serial micro-crystallography: MiTeGen MicroMeshes™, Greiner Bio-One Ltd in situ micro-plates, and a moving kapton crystal conveyor belt that is used to deliver crystals directly into the X-ray beam. 6° wedges of data were taken from ∼100 crystals mounted on each material, and these individual data sets were merged to form nine complete data sets (six from insulin crystals and three from lysozyme crystals). Insulin crystals have a parallelepiped habit with an extended flat face that preferentially aligned with the mounting surfaces, impacting the data collection strategy and the design of the serial crystallography apparatus. Lysozyme crystals had a cuboidal habit and showed no preferential orientation. Preferential orientation occluded regions of reciprocal space when the X-ray beam was incident normal to the data-collection medium surface, requiring a second pass of data collection with the apparatus inclined away from the orthogonal. In addition, crystals measuring less than 20 µm were observed to clump together into clusters of crystals. Clustering required that the X-ray beam be adjusted to match the crystal size to prevent overlapping diffraction patterns. No additional problems were encountered with the serial crystallography strategy of combining small randomly oriented wedges of data from a large number of specimens. High-quality data able to support a realistic molecular replacement solution were readily obtained from both crystal types using all three serial crystallography strategies.

  2. Cause analysis of and measures against frequent belt conveyor high-voltage motor faults%带式输送机高压电动机故障频发的原因分析及对策

    Institute of Scientific and Technical Information of China (English)

    薛永杰

    2011-01-01

    The paper carries out field studies specific to the frequent phenomenon that the high-voltage motor is burned in the belt conveyor system, and finds out the root causes that led to the accidents. thereby effectively prevent the impact on the production imposed hy the motor fault.%针对带式输送机系统频繁出现的高压电动机烧毁现象进行现场研究,找出了事故发生的根源,从而有效避免了电动机故障对生产的影响.

  3. 带式输送机盘式制动器转速测量研究%Study on measurement of rotational speed of disc brakes for belt conveyors

    Institute of Scientific and Technical Information of China (English)

    吴向凡; 尹作振

    2012-01-01

    针对带式输送机盘式制动器转速测量误差较大及跳变问题,提出了一种有效的转速测量方法,根据该方法对盘式制动器转速测量系统进行了设计,并开展了相关试验研究。结果表明,该测速方法可有效提高盘式制动器超速控制精度和稳定性,满足带式输送机的速度控制要求。%In view of large measurement error and transient change of rotational speed of the disc brake for the belt conveyor, an effective measurement method for rotational speed was proposed. According to the method, a system of measuring the rotational speed of the disc brake was designed, and related test study was conducted. The results showed that the measurement method could effectively improve the precision and stability of overspeed control of the disc brake as well as satisfy the speed control requirements of the belt conveyor.

  4. Application of Explosion-proof Hydraulic Station for Cable Belt Conveyor%钢绳牵引皮带运输机防爆液压站的应用

    Institute of Scientific and Technical Information of China (English)

    常胜涛

    2012-01-01

    PY-140B液压站是专门为钢带机制动器配套设计制造的,它和制动器组合成一套制动系统,当压力油进入制动器油缸推动活塞,碟形弹簧成松闸状态,使钢带机正常运输;当油缸内压力下降时,碟形弹簧复位、推动活塞向前,使闸瓦接触制动盘,实现安全制动;当主机工作发生故障时,能紧急制动使主机安全、可靠的停车。%PY-140B hydraulic station is exclusively designed and manufactured for the brake of cable belt conveyor as a set of braking system with the brake,in which the cable belt conveyor works normally when pressure oil enters the brake cylinder,pushes the piston and makes the disk spring loosen;safe braking is realized when the brake shoe contacts the brake with the pressure oil decreasing,the disk spring resetting and pushing the piston forward;and emergency braking makes the main engine shutdown safely and reliably when the main engine breaks down.

  5. Simulation method to assess dynamic behaviour of belt conveyor systems. From theory to practical application; Simulationsmethode zur Beurteilung des dynamischen Verhaltens von Gurtfoerderanlagen. Vom Stand des Wissens zum Stand der Technik

    Energy Technology Data Exchange (ETDEWEB)

    Griesshaber, J.; Beyer, W. [MAN TAKRAF Foerdertechnik GmbH, Leipzig (Germany); Kunze, G.; Graul, S. [Technische Univ. Dresden (Germany). Inst. fuer Foerdertechnik, Baumaschinen und Logistik (Germany)

    1999-03-01

    With the aid of the simulation method described in this paper it is possible to model the nonsteady and steady operating performance of belt conveyor systems. The simulation results are a valuable aid to the designer, particularly when technical decisions have to be reached. With the modular system comprising diverse model components, creation of the model on the PC is greatly simplified. The definition and designation of the model parameters are listed in tabular form. Parameter data sets obtained for actual projects are stored in a data base. Measured values obtained on actual plants are used to verify the models. This simulation method is a modern design tool that is applied in actual practice. It is used to achieve the technical, operational and economic optimization of belt conveyor systems which in some cases entail heavy costs. (orig.) [Deutsch] Mit dem geschaffenen Simulationsverfahren ist es moeglich, das instationaere und stationaere Betriebsverhalten von Gurtfoerderanlagen nachzubilden. Die Simulationsergebnisse dienen dem Projektanten vorrangig bei technischen Entscheidungen. Mit dem geschaffenen Baukastensystem vielfaeltiger Modellkomponenten wird die Handhabung der Modellgestaltung am PC sehr vereinfacht. Die Definition und Benennung von Modellparametern ist menuegefuehrt. Erstellte Parameterdateien fuer konkrete Projekte werden in einer Datenbank verwaltet. Zur Verifizierung der Modelle dienen Messwerte von realen Anlagen. Das Simulationsverfahren stellt ein modernes, in der Praxis eingefuehrtes Projektierungswerkzeug dar. Es dient der technischen und betriebswirtschaftlichen Optimierung von z.T. sehr kostenintensiven Gurtfoerderanlagen. (orig.)

  6. Applications of overburden conveyor bridges

    Energy Technology Data Exchange (ETDEWEB)

    Schachtschneider, H.

    1987-06-01

    In large scale surface mines of the capacities required today, a cross-pit operation with overburden conveyor bridges is the most economical method of overburden removal and disposal. In order to provide the production capacity required in surface mining equipment by the GDR brown coal industry, VEB Schwermaschinenbau Lauchhammerwerk undertook the design and manufacture of standard overburden conveyor bridges for cut heights of 34 m, 45 m and 60 m. All three base types may be equipped to match the site specific geological and geotechnical conditions, and to meet customer's demands. Specifications of the bridges are given as well as details of conveyor belt speeds, modifications to the standards, and number manufactured. Design problems faced with the 60 m bridge are discussed, together with details of the superstructure, method of operation, transportation rates, structural steel used, assembly and power supply. 5 refs.

  7. Belt-up!

    Energy Technology Data Exchange (ETDEWEB)

    Woof, M.

    1999-07-01

    Advanced control systems, improved materials and new dust control systems have turned the humble conveyor belt into a sophisticated method for transporting materials. RJB Mining has improved productivity at the Price of Wales colliery in Yorkshire, UK, with the installation of Alstom`s VDM drive system; Qualter Hall`s upgraded conveyor system at the Rugely Power Station in the UK is proving its ability to minimise coal spillage. The article highlights advances by several manufacturers in conveyor technology. 5 photos.

  8. Load determination of truss beam and internal force calculation of member bar for pipe belt conveyor%圆管带式输送机桁架梁载荷确定及杆件内力计算

    Institute of Scientific and Technical Information of China (English)

    王坚; 韩刚; 樊涛

    2012-01-01

    分析了圆管带式输送机平行弦桁架梁所承受的载荷类型,并给出了载荷大小的确定方法,对桁架梁各杆件的受力特点进行分析,运用截面法得出最危险杆件的内力简化计算公式.%This paper analyzes types of the loads carried by parallel string truss beam of pipe belt conveyor, proposes the load determination method, and analyzes the load-carrying characteristics of member bars of the truss beam, so that ihe internal force simplified calculation formula for the most dangerous member bar is figured out by the section method.

  9. Working Principle and Structure Design of Conveyor Belt Joint Cross-Sectional Layered Machine%输送带接头剖层机工作原理及结构设计

    Institute of Scientific and Technical Information of China (English)

    金伟; 毛杰; 梁存真

    2015-01-01

    本文通过对橡胶输送带接头剖层机的工作原理研究,以剖层机的刀架和同步链轮组为代表的典型机构在加工过程中所要实现的功能和剖层机工作时运动进行探讨分析,针对提高橡胶剖层机的加工效率和降低加工过中的摩擦阻力提出了具体方法,就整机质量在结构、材质上进行了比对优化,为输送带接头快速黏结工艺推广应用,进行了基础设备探讨研究.%Through the study on the principles of rubber conveyor belt jointcross-sectional layered machine, this paper discussed and analyzed the functions to be achieved and the work movement of cross-sectional layered ma-chine for the typical institution with tool holder and synchronous sprocket set of the cross-sectional layered ma-chine as representatives during processing, put forward specific method to improve processing efficiency and re-duce frictional resistance in the processing of rubber cross-sectional layered machine, compared and optimized the quality of the whole machine in structure and materials for promotion and application of conveyor belt joint rapid bonding process, and conducted basic device research and discussion.

  10. 不停机调节带式输送机托辊偏置角的方法%Method for Adjusting Bias Angle of Rollers when Belt Conveyor Running

    Institute of Scientific and Technical Information of China (English)

    王海斌; 李允旺; 白森; 贾正乾; 陈井刚

    2015-01-01

    Adjusting the bias angle of the roller of the belt conveyor is a common method to adjust the belt deviation. The paper introduces two method for adjusting the bias angle of the rollers when the belt conveyor running. The first method is using a longer shaft roller, the end of the extension shaft is lengthened. There is a longer part of the shaft outside the roller supporting, after the roller is installed on the supporting roller. The outer end of the roller shaft can be lifted and moved to other shaft slot, by hand and using other tools. The second method is using a roller frame which can adjusting the bias angle of the rollers. Second, adopt the bracket which has adjustable offset angle of the roller frame, and the roller frame outer end is provided with a slide deck which can regulate the position through screw, supporting roller shaft end clamping on the slider deck. By turning the screw to regulate the slide deck’s position, to realize the regulating of the supporting roller’s offset angle. That two methods are applied in the belt conveyor of Shanxi Lexus of Coal Industry Co. Ltd. and it is highly effective, safety, and offset regulating effect good when the supporting roller’s offset angle is adjusted.%调节托辊的偏置角是对带式输送机输送带调偏的一个常见方法,介绍了2种不停机调节托辊斜置角的方法。①使用轴端加长的托辊;该托辊一端的伸出轴被加长,安装在托辊架上后,托辊支撑座的外侧伸出一段较长的轴段。可徒手或借用工具将托辊外端抬起,并移至其他卡槽内;②采用可调托辊偏置角的托辊架,该托辊架外端设有可通过螺杆调节位置的滑块卡座,托辊轴的外端头卡装在滑块卡座上。通过转动螺杆调节滑块卡座位置,实现托辊偏置角的调节。这2种方法在山西凌志达煤业有限公司的多部带式输送机上得以应用,调整托辊偏置角时高效、安全,调偏效果良好。

  11. Flow field simulation and structure optimization of confined hood at transshipment point of coal conveyor belt%输煤皮带转载点密闭罩流场模拟与结构优化

    Institute of Scientific and Technical Information of China (English)

    吕太; 车晟; 郭澄昆; 王旭东

    2013-01-01

    To study the effect of flow field on the dust absorption performance in a confined hood,numerical simulation of the gas-solid two-phase flow in a confined hood used in transshipment point of coal conveyor belt was carried out with Fluent.The analysis of gas flow field and distribution of coal dust concentration indicates that,with a larger flow deflection at chute turning point,the coal dust concentration will increase and the local coal dust accumulates more correspondingly.In addition,the analysis reveals that placket angle of the dust exhaust hood also had important influence on the dust absorption performance.In order to divert the gas flow as well as enhancing the effect of dust absorption,some optimization designs about the structure of chute turning point and the dust exhaust hood were devised.The result shows that,gas flow field and distribution of coal dust become more uniform and the dust absorption performance is improved after the optimization.Therefore,the present study provides some guidance for the optimization design of confined hood at the transshipment point of coal conveyor belt.%为了研究输煤皮带转载点密闭罩内流场对吸尘效果的影响,采用Fluent软件对某转载点密闭罩内气固两相流动情况进行了数值模拟.通过气流分布和煤尘浓度分布的分析,发现溜槽转折处较大的气流偏转会增加煤尘起尘量和导致局部煤尘积聚,吸尘罩的开口角度对吸尘效果也有较大影响.为了疏导气流并加强吸尘效果,提出了溜槽转折处和吸尘罩的结构优化设计方案.研究表明,改进后气流分布更加均匀,吸尘效果有所提高,从而为转载点密闭罩的优化设计提供了参考.

  12. GCD无齿轮传动在超大型主斜井带式输送机设计中的运用%Application of GCD gearless driving in the design of belt conveyor for very large main inclined draft

    Institute of Scientific and Technical Information of China (English)

    谢永刚

    2014-01-01

    阐述了中煤大海则煤矿主井带式输送机前期驱动系统方案的设计及选用论证,介绍了国外用于特大功率带式输送机驱动系统的传动方式———GCD无齿轮传动系统,该传动方式的设计理念将给传统带式输送机的传动方式的设计理念和思路给予一定启示。%The earlier design and selection of driving system for belt conveyor used in main draft of Dahaize Coal Mine of China National Coal Group Corporation were expounded�� GCD gearless driving system,used for ultrahigh power belt conveyor in abroad,was introduced��This kind of driving mode will bring a certain inspiration for the driving design of conventional belt conveyor.

  13. Investigation on fire cause of coal belt conveyor gallery fire in power plant%对电厂输煤栈桥火灾原因调查认定

    Institute of Scientific and Technical Information of China (English)

    特木尔巴根

    2011-01-01

    通过现场勘查、调查询问、现场试验评估、走访群众、物证鉴定等方法和措施对内蒙古华润金能热电有限公司4号输煤栈桥火灾开展环境和初步勘查、细项和专项勘查,并对起火部位认定情况及依据、起火原因进行了全面、客观、公正的分析.%By fire scene inquisition, fire investigation, fire scene test, people interview and identification of material evidence, environmental and preliminary and comprehensive investigation were made on No. 4 coal belt conveyor gallery fire in inner Mongolian division of huarun thermal power co. · and objective and impartial analysis was made about fire site identification and fire cause.

  14. Application of Fly Ash Based Flame Retardant in Compound of Conveyor Belt%粉煤灰基阻燃剂在阻燃输送带胶料中的应用研究

    Institute of Scientific and Technical Information of China (English)

    于立东; 肖建斌

    2015-01-01

    研究粉煤灰基阻燃剂替代硼酸锌、季戊四醇、聚磷酸铵和磷酸三甲苯酯在丁腈橡胶(NBR)/氯化聚乙烯(CM)阻燃输送带胶料中的应用。结果表明:粉煤灰基阻燃剂可以替代或部分替代硼酸锌、季戊四醇和聚磷酸铵,胶料的加工性能、物理性能和阻燃性能变化不大,热稳定性显著提高,燃烧前期抑烟效果较好。%The application of lfy ash based lfame retardant in compound of conveyor belt was investigated. The fly ash based flame retardant was used to replace conventional flame retardants, for example, zinc borate, pentaerythritol, ammonium polyphosphate and tricresyl phosphate, in NBR/chlorinated polyethylene (CM) blends. The results showed that lfy ash based lfame retardant could replace or partially replace zinc borate, pentaerythritol and ammonium polyphosphate. The processing properties of compound, the physical properties and lfame retardant properties of the vulcanizates were kept unchanged, and the thermal stability and smoke suppression in early combustion stage were improved.

  15. Design of a Disk Brake for Belt Conveyor Hydraulic Control System Design%一种带式输送机盘式制动器液压控制系统的设计

    Institute of Scientific and Technical Information of China (English)

    曹秀洪

    2013-01-01

      文中基于盘式制动器设计了一个液压控制系统,该系统的设计是针对带式运输机在运输过程中的控制问题设计的,所以它的稳定性能和反映能力都占有绝对的优势。文中简单的介绍了液压系统遇到松闸过程、保压过程、正常停车、超速制动、紧急制动和系统突然断电等情况时的运行状况。%  Based on the design of disk brake on a hydraulic control system, the system design is for the belt conveyor in the transportation process control design, so its stability properties and screening ability has the absolute advantage. This paper introduces the hydraulic system of brake loosing process, encountered pressure, normal parking, overspeed braking, emergency braking and system failure, when the running state airport.

  16. Design and Analysis of Hydraulic System of Disc Brake for Downward Belt Conveyor%下运带式输送机盘式制动器液压系统设计与分析

    Institute of Scientific and Technical Information of China (English)

    刘灿杰; 贾跃虎; 刘志奇

    2011-01-01

    通过分析下运带式输送机制动工况的特点以及盘式制动器的优点,设计出适合各制动工况要求的新型盘式制动器液压系统.该液压系统具有松闸、保压、正常停车制动、超速制动、紧急制动和系统突然断电制动等功能.建立了系统的数学模型,将数学模型线性化后推导出了系统传递函数,分析了各元件参数对系统响应性的影响,为设计压力精细调节的制动器提供了理论基础.%The characteristics of braking condition of downward belt conveyor and advantages of disc brake were analyzed. A new hydraulic system of disc brake which met each braking condition requirement was designed. This hydraulic system have functions of loose braking, the normal parking braking, emergency braking and suddenly lose power braking. The mathematical model of this hydraulic system was established. The transfer function of this hydraulic system was deduced by the mathematical model linearization. The influences of the parameters to the response of the system were analyzed. The research work lays theory foundation for the design of brake with pressure fine adjustment.

  17. 变频驱动带式输送机功率平衡控制研究%Research on Power Balance Control of Belt Conveyor with Variable Frequency Drive

    Institute of Scientific and Technical Information of China (English)

    邢金岭

    2014-01-01

    针对带式输送机在运行过程中电动机功率不平衡的问题,提出按转矩进行负荷分配,在基于功率跟踪控制策略的基础上,确定主电动机采用速度闭环的变频调速方式,从电动机为由主电动机提供转矩给定的控制方式;主、从电动机在转矩分配给定的基础上采用无速度传感器的直接转矩控制与空间电压矢量调制相结合的控制方式,可以对转矩进行直接控制而保证功率平衡,同时通过磁通优化改善电动机运行性能。通过MATLAB仿真和实际现场应用参数验证了此方法可以有效地进行输出转矩分配,并实现功率平衡控制。%According to motor power imbalance issue during the operating process of belt conveyors,a novel control mode was proposed,the master machine adopted close-loop frequency control,and the torque reference of the slave was provided by the master based on power tracking strategy.Both of master and slave adopted the control mode combining direct torque control without speed sensor and space vector modulation control based on the torque distribution given,which could directly control the torque and ensure power balance,while improving motor performance by optimizing magnetic flux.It was verified through MATLAB simulation and field tests that the proposed method could effectively allocate the output torque and realize power balance.

  18. Smart Idlers: RFID in conveyor belt monitoring

    NARCIS (Netherlands)

    Pang, Y.

    2012-01-01

    Radio Frequency Identifi cation (RFID) is a technology that offers unique identifi cation of objects and processes. It can actively or passively communicate and, in combination with sensors, it can capture more detailed physical information. RFID technology has been integrated into our daily life.

  19. The Vibration Wave of Continuous and Automatic Water, Water-Saving Washing Device for Belt Conveyor Systems%采用水中振动波进行输送机网的连续式、自动、节水型洗净装置

    Institute of Scientific and Technical Information of China (English)

    丹羽纪雄

    2016-01-01

    The study introduced the operating principle of KOMATSUBARA FV washer,this continuous and automatic water, water-saving washing device could be applyed to belt conveyor systems in food factory,there was a advantage of high detergency and reducing cost, so that improved the health situation in food factory.%本研究介绍了KOMATSUBARA FV洗涤机的工作原理,这种采用水中振动波的连续式、自动、节水型洗净装置能够用于食品加工厂输送机网的洗涤,洗净效果优良,能够降低生产成本,提高食品生产的卫生状态。

  20. 有机蒙脱土/氯丁橡胶纳米复合材料的结构与性能及在输送带中的应用%Structure and Properties of OMMT/CR Nanocomposite and Its Application in Conveyor Belt

    Institute of Scientific and Technical Information of China (English)

    谷正; 单春鹏; 李培耀; 宋国君; 王立; 杨晓宇

    2012-01-01

    The OMMT/CR nanocomposite was prepared by mechanical blending method, and its structure,properties and application in conveyor belt were investigated. It was found that the halfexfoliated OMMT/CR nanocomposite with uniform dispersion of OMMT was prepared. The reinforcement of OMMT to CR was good,the tensile strength and tear strength of OMMT/CR nanocomposite increased significantly by only using 3 phr OMMT,and the thermal aging property improved. By using OMMT to partially replace carbon black in the cover compound of conveyor belt, the tensile strength and tear strength of compound increased slightly,and the wear resistance increased significantly.%采用机械共混法制备有机蒙脱土(OMMT)/氯丁橡胶(CR)纳米复合材料,对复合材料的结构、性能及在输送带中的应用进行研究.结果表明:采用机械共混法能够制备分散均匀的半剥离型OMMT/CR纳米复合材料;OMMT对CR具有良好的补强作用,当OMMT用量仅为3份时,复合材料的拉伸强度和撕裂强度显著提高,耐热空气老化性能改善;在输送带覆盖胶中采用OMMT部分替代炭黑,覆盖胶的拉伸强度和撕裂强度略有增大,耐磨性能显著提高.

  1. Study of thermal conditions at belt slippage

    Energy Technology Data Exchange (ETDEWEB)

    Hoffmann, R.; Pampel, W.; Pfleger, P.

    1987-04-01

    Conveyor belt slippage experiments are carried out on the Chrudim (Czechoslovakia) industrial sized test stand for belt widths up to 1 m and driving drum forces up to 400 kW. The stand is operated jointly by TAKRAF (GDR) and VITKOVICE VUTZ, Prague. From 1972 to 1981, 7 belt conveyor fires occurred in GDR brown coal surface mines due to belt slippage. One of these cases led to a belt fire after only 15 s at 100% belt slippage. Aim of the study was to determine accurate permissible slippage values. Design of the test stand is explained as well as test procedures with belt slippage at the driving drum varying between 10 and 100%. Belt driving parameters were measured along with temperature of the drum surface. The heat penetration parameter b (in kJ/m/sup 2/) was calculated. Maximum temperatures up to 150 C were measured on the drum during partial slippage and 370 C at 100% belt slippage. The ignition temperature of rubber abrasion fines was also analyzed and found to vary between 40 and 318 C, i.e. substantially lower than belt and drum layer ignition temperatures. Graphs and diagram of slippage measurement results are calculated. Values for permissible maximum slippage time for operating belt slippage monitoring devices are shown. These devices are required to be installed in the GDR at heavy mine belt conveyors with driving forces exceeding 500 kW. 8 refs.

  2. 基于环形耦合策略的带式输送机多机驱动功率平衡的研究%Research on power-balance of multi-motors in belt conveyor based on ring coupling control strategy

    Institute of Scientific and Technical Information of China (English)

    汤伟; 李含君

    2013-01-01

    In order to achieve the power-balance in multi-motor driving belt conveyor system , the ring coupling control strategy is adopted .Modeling for master-slave control and ring coupling control of a three-motor system which based on the fuzzy PID control model were established in the simulation circumstance of Matlab .Simulation results show that the ring coupling control strategy has higer synchronization accuracy and better dynamic performance ,the control demand for power balance of multi-motors in belt coneyor is satisfied .%针对多电机驱动的带式输送机中出现各电机功率不平衡的问题,提出了一种适用于多电机的基于环形耦合策略的功率平衡控制方案。在采用模糊PID的基础上,对三个电机主从控制和环形耦合控制分别进行了建模,并用M atlab进行仿真。仿真结果表明:采用环形耦合控制策略具有更高的同步精度和更好的动态性能,满足带式输送机功率平衡控制的要求。

  3. Current conveyors variants, applications and hardware implementations

    CERN Document Server

    Senani, Raj; Singh, A K

    2015-01-01

    This book serves as a single-source reference to Current Conveyors and their use in modern Analog Circuit Design. The authors describe the various types of current conveyors discovered over the past 45 years, details of all currently available, off-the-shelf integrated circuit current conveyors, and implementations of current conveyors using other, off-the-shelf IC building blocks. Coverage includes prominent bipolar/CMOS/Bi-CMOS architectures of current conveyors, as well as all varieties of starting from third generation current conveyors to universal current conveyors, their implementations and applications. •Describes all commercially available off-the-shelf IC current conveyors, as well as hardware implementations of current conveyors using other off-the-shelf ICs; • Describes numerous variants of current conveyors evolved over the past forty five years; • Describes a number of Bipolar/CMOS/Bi-CMOS architectures of current conveyors, along with their characteristic features; • Includes a comprehe...

  4. Versions of transfer conveyors

    Energy Technology Data Exchange (ETDEWEB)

    Goehring, H. (Technische Universitaet, Dresden (German Democratic Republic))

    1990-05-01

    Compares technical specifications of heavy surface mining transfer conveyors built by the manufacturers TAKRAF, O K, Krupp, Buckau-Wolff, Voest-Alpine and others. Equipment is mainly used in brown coal surface mining; its haulage capacity ranges between 600 and 9,300 m{sup 3}/h. Significant specifications of equipment design are considered to be length relation of the two booms for bulk receiving and transfer, as well as total equipment mass. The best length relation has the value 1.1. Further graphs compare the relation of equipment mass, haulage capacity and transfer boom length. Various design advantages of selected equipment series are outlined. 13 refs.

  5. 西秦岭隧道连续皮带机出碴下的同步衬砌施工组织管理%Construction Organization Management for Synchronous Lining Casting in the Case of Continuous Belt Conveyor Mucking System:Case Study on West Qinling Tunnel

    Institute of Scientific and Technical Information of China (English)

    戴润军; 杨永强

    2011-01-01

    为减小衬砌施工与掘进施工的相互干扰,提高衬砌施工进度、缩短工期、降低工程安全风险,从设备管理、施工管理、劳动组织管理3方面介绍了TBM正常掘进时连续皮带机在出碴情况下的同步衬砌情况。通过合理的协调组织,实现了TBM掘进与衬砌施工的同步,有效缓解了本工程工期压力。%The synchronous lining casting in the case of belt conveyor mucking system during TBM boring is presented in terms of equipment management,construction management and labor organization,so as to minimize the influence between the lining casting and TBM boring,shorten the construction period and reduce the safety risks.In the end,the synchronization between TBM boring and lining casting is realized,which effectively relieves the pressure on the construction schedule.

  6. Analytical Method of Designing and Selecting Take-Up Systems for Mining Belt Conveyors / Analityczna Metoda Projektowania i Doboru UKŁADÓW Napinania Dla GÓRNICZYCH PRZENOŚNIKÓW TAŚMOWYCH

    Science.gov (United States)

    Kulinowski, Piotr

    2013-12-01

    This article presents a method developed to design and select tensioning systems which makes use of standard calculations. It describes procedures for selecting and analysing the operation of devices tensioning the belt, which procedures are based on the static characteristics of these devices, and a proposal for introducing a substitute belt elasticity modulus that would make the calculations of the tensioning stroke length account for the value of the initial force tensioning the belt and for its sag between sets of idlers. Static characteristics of tensioning systems have been used to describe their operation and present the advantages and disadvantages of individual design solutions W artykule przedstawiono opracowaną metodę projektowania i doboru układów napinania taśmy wykorzystującą stosowane standardowe procedury obliczeniowe uzupełnione o zależności analityczne uwzględniające zwis taśmy między zestawami krążnikowymi i charakterystyki statyczne urządzeń napinających taśmę. W pierwszej części publikacji opisano analityczną metodę doboru układu napinania taśmy bazującą na wynikach obliczeń sił w taśmie i szacunkowych kalkulacjach drogi napinania taśmy stosowanych obecnie w standardowych procedurach obliczeniowych (Golka i in., 2007; Gładysiewicz, 2003; Żur i Hardygóra, 1996). Następnie przedstawiono propozycję uzupełnienia stosowanej metody analitycznej o wprowadzenie diagramu drogi napinania i uwzględnienie zastępczego modułu sprężystości taśmy (Kulinowski, 2012). W obliczeniach standardowych przyjmuje się, że długość odcinka taśmy pomiędzy zestawami krążnikowymi jest równa ich rozstawowi. W rzeczywistych warunkach może się zdarzyć, że na niektórych odcinkach złożonego profilu trasy przenośnika wartość zwisu taśmy przekracza wartości dopuszczalne, wtedy długość taśmy między zestawami krążnikowymi jest znacząco większa od rozstawu zestawów. W takich przypadkach wartość modułu spr

  7. Adaptive Design of SZZ800 Reproduced Conveyor Coordinated with the SGZ1250 Scraper Conveyor%SZZ800转载机配套SGZ1250刮板输送机适应性设计

    Institute of Scientific and Technical Information of China (English)

    齐志贤

    2013-01-01

      转载机与输送机是综合化机械运输系统的重要组成部分。转载机将刮板输送机卸载的煤炭经转载机(包括破碎机碎后)提升并卸载到顺槽皮带机上。通过设计改造能够使设备在狭小空间安装使用。%  Reproduced Conveyor and Scraper Conveyor are important parts of the comprehensive mechanized transport system. Reprint machine scraper conveyor unloads coal by the transfer machine (including crusher broken) to ascend and unload into the trough belt conveyor. Through the design, it can be installed and used in narrow space.

  8. Noise Properties of CMOS Current Conveyors

    DEFF Research Database (Denmark)

    Bruun, Erik

    1996-01-01

    The definition of the current conveyor is presented and it is shown how different generations of current conveyors can all be combined into a single definition of a multiple-output second generation current conveyor (CCII). Next, noise sources are introduced into the model, and a general noise...... model for the current conveyor is established. This model is used for the analysis of selected examples of current conveyor based operational amplifier configurations and the relative merits with respect to the noise performance of these configurations are discussed. Finally, the noise model...... is developed for a CMOS current conveyor implementation, and optimization strategies for noise reduction are discussed. It is concluded that a class AB implementation provides more flexibility than does a class A configuration. In both cases it is essential to design low noise current mirrors and current...

  9. A Nanofiber-Based Optical Conveyor Belt for Cold Atoms

    CERN Document Server

    Schneeweiss, Philipp; Mitsch, Rudolf; Reitz, Daniel; Vetsch, Eugen; Rauschenbeutel, Arno

    2012-01-01

    We demonstrate optical transport of cold cesium atoms over millimeter-scale distances along an optical nanofiber. The atoms are trapped in a one-dimensional optical lattice formed by a two-color evanescent field surrounding the nanofiber, far red- and blue-detuned with respect to the atomic transition. The blue-detuned field is a propagating nanofiber-guided mode while the red-detuned field is a standing-wave mode which leads to the periodic axial confinement of the atoms. Here, this standing wave is used for transporting the atoms along the nanofiber by mutually detuning the two counter-propagating fields which form the standing wave. The performance and limitations of the nanofiber-based transport are evaluated and possible applications are discussed.

  10. Water: The conveyor belt for sustainable livelihoods and economic development

    Science.gov (United States)

    Mapani, Benjamin; Meck, Maideyi; Makurira, Hodson; Magole, Lapologang; Mashauri, Damas; mazvimavi, Dominic; Mul, Marloes

    2016-04-01

    The theme for the 2014 symposium focused on the contribution of integrated water resources management (IWRM) to socio-economic development. A number of papers presented various methods that could be used to enable society to access clean water; sanitation and provision of water for rainfed and irrigation based agriculture and aquaculture. Water is the engine of development, that drives both money generating ventures as well as activities which cannot be assigned exact monetary value, but are essential for the social and economic well being of communities. It is now accepted that in order to produce most products, the contribution of water has to be factored in; from manufacturing to mining. The role that water plays in the has a much higher economic value than most people realize.

  11. WIRELESS SENSOR NETWORK BASED CONVEYOR SURVEILLANCE SYSTEM

    OpenAIRE

    Attila Trohák; Máté Kolozsi-Tóth; Péter Rádi

    2011-01-01

    In the paper we will introduce an intelligent conveyor surveillance system. We started a research project to design and develop a conveyor surveillance system based on wireless sensor network and GPRS communication. Our system is able to measure temperature on fixed and moving, rotating surfaces and able to detect smoke. We would like to introduce the developed devices and give an application example.

  12. Joy flexible conveyor train demonstration at Box Flat Colliery

    Energy Technology Data Exchange (ETDEWEB)

    O' Beirne, T.; Napper, A.

    1988-01-01

    Australia's first continuous and flexible face haulage system, the 100 m long Joy 2 Flexible Conveyor Train (FCT), has been installed and trialled. This Joy FCT has, successfully transported 198,334 tonnes of coal from both production drivage and partial pillar extraction. The machine has matched, or exceeded, all of its manufacturer's written specifications except the belt life-span. The only major problem during its use was the replacement of the complete belt at 75,629 tonnes due to internal delamination and the replacement of 2 sections at 173,569 tonnes to try a new batch. The fault appears to be a batch quality control problem. The FCT was installed in conjunction with a rebuilt Jeffrey 120H2 continuous miner and Joy 10SC6 shuttle car modified by the inclusion of a rotary pick breaker and a boom extension. The modified 10SC6 was used to control surges and limit product top size. It acted as a flexible buffer between the miner and the FCT bridge conveyor. In general, the FCT itself has demonstrated its maker's claims and the expectations of the colliery management. The rebuilt face equipment has not been as reliable. The cyclic nature of cutting, machine moves and bolting was definitely the limiting factor in the overall performance of the mining system. In the latter stages of the trial, the 10SC6 was removed totally with some adverse results. The shuttle car based feeder breaker cannot be considered an outstanding success, however, it was a good starting point.

  13. Device for relocating a covered conveyor

    Energy Technology Data Exchange (ETDEWEB)

    Kirilin, V.S.; Aksanov, Sh.I.; Bodendorf, B.A.; Kazakovtseva, M.V.; Solov' yev, I.N.

    1979-04-28

    The innovation applies to mechanized underground coal extraction and can be used to relocate a covered conveyor on rails when working steep seams by the drilling-explosive method. The well known mechanism for relocating the conveyor includes hydraulic jacks, a vertical feed, extensions linked to the conveyor and anchors on the cylinder fastened with hinges to the guard cover, joints, and cylinders which are directly attached to the cover. In this mechanism the vertical feed joints are linked to the hoist joints by sliding chains; this causes unreliable sturdiness in raised positions. The sliding chains permit vibration in large dynamic loads and breakdowns under the effects of shock waves. This prevents effective use of the mechanism during drilling-explosive extraction. The invention allows the equipment to be removed from the danger zone during the drilling-explosive coal extraction. The device relocates the protected conveyor on rails when a thick, steep layer is being thus worked out.

  14. Pickering irradiated fuel transfer conveyor isolation

    International Nuclear Information System (INIS)

    Pickering A NGS has been in operation for 25 years and is one of the longest in service CANDU stations. Some underwater fuel handling equipment, notably the conveyor stops, have been without maintenance throughout that time. This paper describes the concept of a conveyor isolation system that permits draining of a single or multiple elevator columns and also the early stages of a development program for the elastomeric sealing element. The prototype seal element has been proven in lab tests to be capable of limiting leakage to 0.5 IGPM (imperial gallons per minute) at the design pressure of 6.5 psi. The design of a sealing element is particularly interesting because the conveyor tube is a square cross-section which contains an additional obstruction , a conveyor drive cable. A seal delivery, actuating and positioning system has been conceptually laid out and the design is proceeding, with projected implementation in 1998. (author). 8 figs

  15. Konstruktion av current conveyors via makromodellering

    OpenAIRE

    Hjalmarsson, Erik

    2004-01-01

    A current conveyor is an active building block that can be used to implement most active and passive components. It differs from the operation amplifier in that it uses current instead of voltage. The current conveyor also has significantly higher voltage gain over a broader frequency range. To simplify the construction of analogue circuits and increase the construction efficiency it is desirable to use a top-down methodology. This means that the whole system is partitioned into a hierarchy ...

  16. Wear of conveyor chains with polymer rolls

    OpenAIRE

    Kerremans, Vincent; Rolly, Tom; DE BAETS, PATRICK; De Pauw, Jan; Sukumaran, Jacob; Perez Delgado, Yeczain

    2011-01-01

    Roller conveyor chains are common used to transport goods in production lines or assembly lines, such as pallets, cars or steel coils. They are sometimes used in severe environments, soiled with water, foreign particles, chemicals or other contaminants. Normal use will result in wear of the components of the chain which can lead to unexpected failure and costly production downtime. Today, few literature on the wear of conveyor chain is available and there are almost no reliable test-rigs to g...

  17. Conveyor with rotary airlock apparatus

    Energy Technology Data Exchange (ETDEWEB)

    Kronbert, J.W.

    1993-01-01

    This invention is comprised of an apparatus for transferring objects from a first region to a second region, the first and second regions having differing atmospheric environments. The apparatus includes a shell having an entrance and an exit, a conveyer belt running through the shell from the entrance to the exit, and a horizontally mounted `revolving door` with at least four vanes revolving about its axis. The inner surface of the shell and the top surface of the conveyer belt act as opposing walls of the `revolving door`. The conveyer belt dips as it passes under but against the revolving vanes so as not to interfere with them but to engage at least two of the vanes and define thereby a moving chamber. Preferably, the conveyer belt has ridges or grooves on its surface that engage the edges of the vanes and act to rotate the vane assembly. Conduits are provided that communicate with the interior of the shell and allow the adjustment of the atmosphere of the moving chamber or recovery of constituents of the atmosphere of the first region from the moving chamber before they escape to the second region.

  18. 29 CFR 1918.63 - Chutes, gravity conveyors and rollers.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Chutes, gravity conveyors and rollers. 1918.63 Section 1918... Equipment Other Than Ship's Gear § 1918.63 Chutes, gravity conveyors and rollers. (a) Chutes shall be of... and gravity conveyor roller sections shall be firmly placed and secured to prevent...

  19. Floating RC Networks Using Current Conveyors

    Directory of Open Access Journals (Sweden)

    V. Zeman

    1996-06-01

    Full Text Available The paper deals with the design of floating one- and/or two-port high-order networks. The current conveyor CCII+ seems to be a suitable active building block for this purpose. Some examples of the above mentioned networks are shown .

  20. Communication equipment for underground conveyor units

    Energy Technology Data Exchange (ETDEWEB)

    Geurts, J.

    1981-06-01

    There are many factors governing smooth operation of a conveyor system. Communication systems are required for fast access to information in case of disturbances. The following possibilities are reported: Use of the existing telecommunication network, use of radio equipment, use of an independent intercommunication system.

  1. Operational experiences with belt rollers for bulk conveying

    Energy Technology Data Exchange (ETDEWEB)

    Dietl, W.

    1982-05-01

    Explains the design of belt rollers produced by TAKRAF for conveyor belts 0.3 m to 3.0 m wide. Light, medium and heavy-duty rollers are manufactured according to a common basic design; the roller diameters range from 63 mm to 245 mm. Major parameters of rollers are discussed, the theoretical roller service life is calculated. Operational conditions which must be observed in order to obtain the theoretical service life in operation are listed. The principle design of the roller is demonstrated in a scheme, focusing on the axial labyrinth seal. Impact forces on rollers at conveyor feeding stations are analyzed. Tests have been carried out using rollers provided with shock absorbing rubber elements compensating the impact load of the bulk, which, however, did not prove to be advantageous. Conclusions on the design of heavy duty rollers to be used at feeding stations are further outlined. (3 refs.) (In German)

  2. Análisis estructural de un transportador de banda. // Structural analysis of a band conveyor.

    Directory of Open Access Journals (Sweden)

    P. Alvarez Barreras

    2001-07-01

    Full Text Available El presente trabajo contiene el análisis de comprobación de la estructura de la cuna de una máquina transportadora debanda. En el mismo se determinan las cargas de servicio y las condiciones de apoyo, se efectúa el cálculo lineal por elmétodo de los elementos finitos, y finalmente se valoran los resultados en forma de:· Análisis de las tensiones.· Análisis de los desplazamientos.· Análisis de las deformaciones.Palabras claves: Transportador de banda, estructura, análisis de tensiones, elementos finitos.________________________________________________________________________________AbstractThe present work contains the structure analysis of a belt conveyor cradle. The operation loads and conditions of supportare determined, the lineal calculation is made by the Finite Element Method, and finally the results are valued in form of:· Analysis of tensions.· Analysis of displacements.· Analysis of deformations.Key words: Belt conveyor cradle, structure, tension analysis, finite element.

  3. Universal Voltage Conveyor and Current Conveyor in Fast Full-Wave Rectifier

    Directory of Open Access Journals (Sweden)

    Josef Burian

    2012-12-01

    Full Text Available This paper deals about the design of a fast voltage-mode full-wave rectifier, where universal voltage conveyor and second-generation current conveyor are used as active elements. Thanks to the active elements, the input and output impedance of the non-linear circuit is infinitely high respectively zero in theory. For the rectification only two diodes and three resistors are required as passive elements. The performance of the circuit is shown on experimental measurement results showing the dynamic range, time response, frequency dependent DC transient value and RMS error for different values of input voltage amplitudes.

  4. Design, fabrication and testing of a low headroom conveyor transfer chute. Final technical report. [Chutes for transferring material from one conveyor to another

    Energy Technology Data Exchange (ETDEWEB)

    Douglas, S. B.; Larson, P.

    1980-12-01

    This document contains the results of tests performed on eight one-sixth scale models of low headroom transfer chutes for underground belt conveyors. The models were evaluated using a methodology technique to select one chute for further full-scale testing in an underground mine. The study concludes that the slide chute should be tested in an underground 90/sup 0/ transfer point. The report contains a state-of-the-art survey, a literature search, data from mine visits, test results, evaluation based on the methodology technique, and a set of guidelines for the design of low headroom transfer chutes. Also included are the preliminary designs of the slide and stone box chutes, scaled up from the designs used in the tests. Following the first phase of the program, the contract was terminated for the convenience of the government; therefore, the program did not progress to the Phase II full-scale chute fabrication or Phase III field testing.

  5. 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...

  6. Optimation of a Table Conveyor Type Grading Machine to Increase the Performance of Green Coffee Manual Sortation

    Directory of Open Access Journals (Sweden)

    Sukrisno Widyotomo

    2006-05-01

    Full Text Available Coffee consumers request a good quality of green coffee to get a good coffee cup taste. Defective beans e.g. black bean, brown bean and broken bean are associated to low coffee quality which give negative effects to final taste. To meet the standard export requirement, coffee beans have to be graded before being traded. Until now, grading process is generally carried out manually. The method gives better product, so the grading cost is very expensive about 40% of total processing cost. Meanwhile, shortage of skill workers is a limiting factor of the process. Therefore, improving the manual sorting by providing machine for grading of green coffee is good alternative to reduce the grading cost. Indonesian Coffee and Cocoa Research Institute has designed a table conveyor type grading machine in order to improve the performance of the manual grading productivity and consistent quality and to reduce the grading cost. The conveyor belt has a dimension of 5700 mm of length, 610 mm of width and 6 mm of thickness. The rotating of belt conveyor powered by an electro motor 3 HP, 3 phase and 1420 rpm. The result showed that the optimum capacity of grading machine was 390 kg/hour reached when the speed 16 rpm and 3 kg/m 2 of green beans on belt conveyor with productivity 1870 kg/man-day compared to the productivity full manually process 743 kg/man-day. Percentage of product in outlet 1 was 4.2% as broken beans, 0.26% as brown beans, 0.68% as one hole in beans and 0.61% as more than one hole in beans. Percentage of product in outlet 2 was 39.54% as broken beans, 4.23% as brown beans 7.19% as black beans, 4.47% as one hole in beans and 4.43% as more than one hole in beans. Cost of grading process per kg of green coffee is Rp20,-. Key words : Coffee, Grading, Conveyor table, Quality

  7. 30 CFR 56.14201 - Conveyor start-up warnings.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Conveyor start-up warnings. 56.14201 Section 56.14201 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Equipment Safety Practices and Operational Procedures § 56.14201 Conveyor start-up warnings. (a) When...

  8. 30 CFR 57.14201 - Conveyor start-up warnings.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Conveyor start-up warnings. 57.14201 Section 57.14201 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Equipment Safety Practices and Operational Procedures § 57.14201 Conveyor start-up warnings. (a) When...

  9. Analysis of the Noise Characteristics of CMOS Current Conveyors

    DEFF Research Database (Denmark)

    Bruun, Erik

    1997-01-01

    is described. This model is used for the analysis of selected examples of current conveyor based operational amplifier configurations and the noise performance of these configurations is compared. Finally, the noise model is developed for a CMOS current conveyor implementation, and approaches...

  10. Installation of FCT continuous haulage system at Box Flat No. 9 Colliery - preliminary results. [Flexible conveyor train

    Energy Technology Data Exchange (ETDEWEB)

    Napper, A.; Kathage, W.; O' Beirne, T.

    1986-01-01

    In November 1985, a Joy 2FCT-IBH monorail Flexible Conveyor Train (FCT) was installed at Wm. McQueen and Co's. Box Flat No.9 colliery in Australia. It is used in conjunction with a continuous miner and breaker car, giving a total length of 122 m. Central to the FCT's operation is the flexible belt conveyor, constructed with the warp and weft of belt at an angle to the longitudinal axis of the belt, allowing it to negotiate four 9 m radii bends. In use so far, loads of up to 10 tonnes/min have been transported up gradients of 1 in 8. The mining method consists of a five heading, seven sequence, bord and pillar mining cycle. A prop-free roadway supported by rows of three fully encapsulated roof bolts at 1.5 m spacings is used. The FCT equipment has been 95% reliable; an average production shift could yield 660 tonnes, a 100% improvement over shuttle cars.

  11. Failure reasons investigations of dumping conveyor breakdown

    Directory of Open Access Journals (Sweden)

    E. Rusiński

    2007-07-01

    Full Text Available Purpose: The main purposes of the paper are to discuss designing and exploitation problems of machines used in strip mines and investigation of its reasons based on steering frame brake-down of the dumping conveyor.Design/methodology/approach: Numerical and experimental approach was used to investigate reasons of the break-down of the dumping conveyor. Numerical simulations based on the finite element method were used. Fractographic and microscopic evaluation and chemical analysis, were used to perform material evaluations. The objectives are achieved by analysis of the numerical simulations results of the broken part of machine and data coming from material evaluations. Based on the mentioned results conclusions concerning results of the failure were given. Additionally the new design of the steering frame half-shafts systems was discussedFindings: The causes of break-down of the steering frame of dumping conveyor were found. Designing and manufacturing problems were the main reasons of the failure. The half shafts systems in undercarriages of the open pit machines are prone to break-downs. They require detailed analysis to be successfully implemented into steering system. Recommendations for the single shaft system are given in the paper.Research limitations/implications: in the half-shaft undercarriage system, the friction in the supporting areas limits horizontal forces acting on safetying. Investigations of the static and sliding friction coefficients should be performed to estimate correct forces and optimal designing rules.Practical implications: The study provides practical implication into designing of half-shafts undercarriage systems and their safetyings. Discussed design of the safetying should be redesigned or the half-shaft system should be changed into one shaft design.Originality/value: The paper provides information backed by evaluation and test results, stating the nexus of causes of the dumping conveyor failure. The

  12. Trial Application of Pulse-Field Magnetization to Magnetically Levitated Conveyor System

    Directory of Open Access Journals (Sweden)

    Yoshihito Miyatake

    2012-01-01

    Full Text Available Magnetically levitated conveyor system using superconductors is discussed. The system is composed of a levitated conveyor, magnetic rails, a linear induction motor, and some power supplies. In the paper, pulse-field magnetization is applied to the system. Then, the levitation height and the dynamics of the conveyor are controlled. The static and dynamic characteristics of the levitated conveyor are discussed.

  13. Automation of belts; Automatizacion de Cintas de Interior

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    This document presents the most important aspects, and the results of the project DEVELOPMENT AND COMMISSIONING OF AN INTEGRATED HAULAGE AND VENTILATION CONTROL SYSTEM IN A MINE USING VERY LONG SUBLEVEL-CAVING WINNING METHOD. Project's targets were to develop, implement and commission a distributed control system for underground mining, which should allow the control and optimisation of the whole (continuous) haulage network. It should also integrate statutory safety features required for both winning and haulage. The system is capable of controlling the most common devices used in underground coal mining transport networks, like conveyor belts, armored conveyors, regulation silos, etc. from the winning faces to the surface, and also the interlocks between them. Moreover, the system implements statutory safety functions for conveyor belt operation, and for mining activities carried out in culls de sac. Specifically, for its relationship with the transport system, it should monitor secondary ventilation, fire damp and toxic gases concentration, and mains power presence in the culls de sac, which have already reached a length of 2000 m. The prototype was installed in the mine that Carbones de Pedraforca owns in Saldes, Barcelona. (Author)

  14. Full-wave current conveyor precision rectifier

    Directory of Open Access Journals (Sweden)

    Đukić Slobodan R.

    2008-01-01

    Full Text Available A circuit that provides precision rectification of small signal with low temperature sensitivity for frequencies up to 100 kHz without waveform distortion is presented. It utilizes an improved second type current conveyor based on current-steering output stage and biased silicon diodes. The use of a DC current source to bias the rectifying diodes provides higher temperature stability and lower DC offset level at the output. Proposed design of the precision rectifier ensures good current transfer linearity in the range that satisfy class A of the amplifier and good voltage transfer characteristic for low level signals. Distortion during the zero crossing of the input signal is practically eliminated. Design of the proposed rectifier is realized with standard components.

  15. Selección de cadenas para equipos de transporte continuo. // Chain selection software for continuous conveyors.

    Directory of Open Access Journals (Sweden)

    F. Aguilar Parés

    2003-01-01

    ón, transportadores de tablillas, transportadores de rastrillos,elevadores de cangilones._____________________________________________________________________________Abstract:The design of conveyors and elevators that employ chains as driving member is commonly used in industry. An essentialelement for well functioning is the correct chain selection. There are a great variety of chains and attachments thataccomplish any requirements at manufacturers disposal. In order to supply these requirements there is a need to establish aprocedure that considers the following aspects:· Type of equipment (slat conveyor, flight conveyor, bucket conveyor, etc..· Transportation requirements (capacity, transportation velocity, material characteristics, etc..· Transportation conditions (overload, operation conditions, explotation time, etc..The resulting procedure is very annoying because there are stages in which a decision implies accommodation to latecalculations and as usual there is more than one solution. Therefore the SELCAD computation program is conceived for theuse by non experts in design and selection of continuous conveyors equipments. The program use data base from Link BeltIndustrial Chain Division catalog in which 14 types of chains are appraise with an average of 15 models for each and morethan 40 different attachments. Some of the program characteristics are:· User friendly environment (Visual Basic programation, version 5.· Help available at any moment.· Point out the characteristics of both driving member and gear.· Allows visualization of the selected real chain shape and attachment by photos.· Quick analysis of different variations.Key words: Transportation chain, slat conveyors, flight conveyor, bucket conveyor.

  16. Floating Inductance and FDNR Using Positive Polarity Current Conveyors

    Directory of Open Access Journals (Sweden)

    K. Pal

    2004-01-01

    Full Text Available A generalized circuit based on five positive polarity second-generation current conveyors is introduced. The circuit simulates a floating inductance, capacitor floatation circuit and floating fdnr. All these circuits use grounded capacitors.

  17. A Review of Screw Conveyors Performance Evaluation During Handling Process

    Directory of Open Access Journals (Sweden)

    Hemad Zareiforoush

    2010-04-01

    Full Text Available This paper reviews recent work on screw conveyors performance evaluation during handling process, especially in the case of agricultural grains and bulk materials. Experimental work has been mainly carried out to determine a range of parameters, such as auger dimension, screw rotational speed, screw clearance, conveyor intake length and conveying angle for horizontal, inclined and vertical screw conveyors. Several measurement techniques including theoretical models and DEM have been utilized to study the screw conveyors performance. However, each of these techniques is limited in its application. Difficulties in representing vortex motion and interactions among conveying grains and between the particles and screw rotating flight have so far limited the success of advanced modeling. Further work is needed to be conducted on screw augers performance to understand and improve the agricultural grains and bulk materials handling process.

  18. Centrifuging Step-Screw Conveyor for Regolith Project

    Data.gov (United States)

    National Aeronautics and Space Administration — A variety of ISRU operations will utilize lunar regolith as feedstock. The proposed centrifuging step-screw conveyor concept will provide a well controlled robust,...

  19. Development of a high capacity longwall conveyor. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Sparks, C

    1982-05-01

    The objectives of this program were to develop, fabricate, and demonstrate a longwall conveying system capable of transporting coal at a rate of 9000 tons/day (1000 tons/hr) and capable of accommodating a surge rate of 20 tons/min. The equipment was required to have the structural durability to perform with an operating availability of 90%. A review of available literature and discussions with longwall operators identified the problem areas of conveyor design that required attention. The conveyor under this contract was designed and fabricated with special attention given to these areas, and also to be easily maintainable. The design utilized twin 300 hp drives and twin inboard 26-mm chain at 270 ft/min; predictions of capacity and reliability based on the design indicating that it would satisfy the program requirements. Conveyor components were critically tested and the complete conveyor was surface-tested, the results verifying the design specifications. In addition, an instrumentation system was developed with analysis by computer techniques to monitor the performance of the conveyor. The conveyor was installed at a selected mine site, and it was the intention to monitor its performance over the entire longwall panel. Monitoring of the conveyor performance was conducted over approximately one-third of the longwall panel, at which point further effort was suspended. However, during the monitored period, data collected from various sources showed the conveyor to have exhibited its capability of transporting coal at the desired rate, and also to have conformed to the program requirements of reliability and availability.

  20. Belt attachment and system

    Science.gov (United States)

    Schneider, Abraham D.; Davidson, Erick M.

    2016-02-02

    Disclosed herein is a belt assembly including a flexible belt with an improved belt attachment. The belt attachment includes two crossbars spaced along the length of the belt. The crossbars retain bearings that allow predetermined movement in six degrees of freedom. The crossbars are connected by a rigid body that attaches to the bearings. Implements that are attached to the rigid body are simply supported but restrained in pitching rotation.

  1. Discrete element modelling of screw conveyor-mixers

    Directory of Open Access Journals (Sweden)

    Jovanović Aca

    2015-01-01

    Full Text Available Screw conveyors are used extensively in food, plastics, mineral processing, agriculture and processing industries for elevating and/or transporting bulk materials over short to medium distances. Despite their apparent simplicity in design, the transportation action is very complex for design and constructors have tended to rely heavily on empirical performance data. Screw conveyor performance is affected by its operating conditions (such as: the rotational speed of the screw, the inclination of the screw conveyor, and its volumetric fill level. In this paper, horizontal, several single-pitch screw conveyors with some geometry variations in screw blade was investigated for mixing action during transport, using Discrete Element Method (DEM. The influence of geometry modifications on the performance of screw conveyor was examined, different screw designs were compared, and the effects of geometrical variations on mixing performances during transport were explored. During the transport, the particle tumbles down from the top of the helix to the next free surface and that segment of the path was used for auxiliary mixing action. The particle path is dramatically increased with the addition of three complementary helices oriented in the same direction as screw blades (1458.2 mm compared to 397.6 mm in case of single flight screw conveyor Transport route enlarges to 1764.4 mm, when installing helices oriented in the opposite direction from screw blades. By addition of straight line blade to single flight screw conveyor, the longest particle path is being reached: 2061.6 mm [Projekat Ministarstva nauke Republike Srbije, br. TR-31055

  2. Key Technology of Mucking by Continuous Conveyor Belt: Case Study on West Qinling Extra-long Tunnel%西秦岭特长隧道连续皮带机出碴施工关键技术

    Institute of Scientific and Technical Information of China (English)

    许金林; 徐赞; 王艳波

    2011-01-01

    Continuous conveyor belt mucking system and synchronous lining system are adopted in the construction of West Qinling tunnel on Lanzhou-Chongqing railway.The conflicts between the continuous conveyor belt mucking system and the synchronous lining system are presented and solutions are proposed.Automatic muck branching device is adopted,which achieves smooth muck transfer between the continuous conveyor belt mucking system and the truck transporting system.Automatic belt releasing and withdrawing device is applied in the works,which achieves successful belt releasing and withdrawing.The practice shows that the conveyor belt mucking technology is helpful to the tunneling in terms of economy,continuity,safety,efficiency and working intensity.The paper can provide reference for the development of continuous conveyor belt mucking technology in China.%以新建兰渝铁路西秦岭隧道同步衬砌下的特长连续皮带机出碴为研究背景,介绍连续皮带机出碴体系与同步衬砌体系的矛盾并提出解决方案,创造性地引入连续分碴器自动切换装车技术以实现连续皮带机出碴与工程车转运2作业工序的无缝衔接;同时,阐述特长连续皮带机转场方案及皮带收放装置在解决出碴体系中途转场过程中如何实现无损伤快速回收、释放皮带难题的应用。实践证明:上述工艺和技术在经济性、连续性、安全性、施工工效、劳动强度等方面都能够更加合理地辅助现场施工,对于推动我国尚处于起步阶段的连续皮带机出碴技术发展具有较强的参考和指导意义。

  3. Programmable Second-Generation Current-Conveyor With Variable Current Gain

    OpenAIRE

    Abdulrafeeq Abdulshakoor; Abdulrahman Khalaf Al-Ali; Muhammad Taher Abuelma'atti

    1995-01-01

    A new programmable second-generation current-conveyor is proposed. The proposed circuit uses a commercially available second-generation current-conveyor and one operational transconductance amplifier. Simulation results confirming the presented theory are included.

  4. On possible flow back in vertical screw conveyors for cohesionless granular materials

    NARCIS (Netherlands)

    Rademacher, F.J.C.

    1981-01-01

    Conditions for which back flow will be initiated in vertical screw conveyors conveying cohesionless granular material are theoretically established. Use is made of existing knowledge of the performance characteristics of such conveyors. Provided the conveyor is operated at not too low an angular spe

  5. Conveyor belt of flesh: urban space and proliferation of the industrial labor practices

    OpenAIRE

    BALABAN, Utku Barış

    2011-01-01

    The second half of the twentieth century witnessed the worldwide (re)emergence of the
    non-factory forms of industrial labor. Academic studies predominantly emphasize the
    economic and political globalization to explain this phenomenon. This thesis investigates
    the local urban dynamics of this „proliferation of the industrial labor practices‟ with a
    field research in Istanbul, Turkey. 
    The field research focused on the organiza...

  6. Piezoelectric driving of vibration conveyors: an experimental assessment.

    Science.gov (United States)

    Rade, Domingos Alves; de Albuquerque, Emerson Bastos; Figueira, Leandro Chaves; Carvalho, João Carlos Mendes

    2013-07-17

    Vibratory feeders or vibratory conveyors have been widely used for the transport and orientation of individual parts and bulk materials in many branches of industrial activity. From the designer's standpoint, the current endeavor is to conceive efficient vibratory feeders, satisfying constraints of power consumption, vibration transmission and noise emission. Moreover, the interest in the reduction of maintenance cost is always present. In this context, this paper investigates experimentally the concept of vibratory conveying based on the use of piezoelectric materials for motion generation. A small-size prototype of a linear conveyor, in which lead-zirconate-titanate (PZT) patches are bonded to the resilient elements, is described. One of the main design goals is that the prototype is intended to be fed directly from the electric network, aiming at avoiding the use of electronic equipment for driving. To comply with this feature and, at the same time, enable to adjust the transport velocity, a mechanical device has been conceived in such a way that the first natural frequency of the conveyor can be changed. It is shown that the transport velocity is determined by the proximity between the excitation frequency and the first natural frequency of the conveyor. The experimental tests performed to characterize the dynamic behavior of the prototype are described and the range of transport velocities is determined.

  7. Piezoelectric Driving of Vibration Conveyors: An Experimental Assessment

    Directory of Open Access Journals (Sweden)

    Emerson Bastos de Albuquerque

    2013-07-01

    Full Text Available Vibratory feeders or vibratory conveyors have been widely used for the transport and orientation of individual parts and bulk materials in many branches of industrial activity. From the designer’s standpoint, the current endeavor is to conceive efficient vibratory feeders, satisfying constraints of power consumption, vibration transmission and noise emission. Moreover, the interest in the reduction of maintenance cost is always present. In this context, this paper investigates experimentally the concept of vibratory conveying based on the use of piezoelectric materials for motion generation. A small-size prototype of a linear conveyor, in which lead-zirconate-titanate (PZT patches are bonded to the resilient elements, is described. One of the main design goals is that the prototype is intended to be fed directly from the electric network, aiming at avoiding the use of electronic equipment for driving. To comply with this feature and, at the same time, enable to adjust the transport velocity, a mechanical device has been conceived in such a way that the first natural frequency of the conveyor can be changed. It is shown that the transport velocity is determined by the proximity between the excitation frequency and the first natural frequency of the conveyor. The experimental tests performed to characterize the dynamic behavior of the prototype are described and the range of transport velocities is determined.

  8. Flexible Mechanical Conveyors for Regolith Extraction and Transport

    Science.gov (United States)

    Walton, Otis R.; Vollmer, Hubert J.

    2013-01-01

    A report describes flexible mechanical conveying systems for transporting fine cohesive regolith under microgravity and vacuum conditions. They are totally enclosed, virtually dust-free, and can include enough flexibility in the conveying path to enable an expanded range of extraction and transport scenarios, including nonlinear drill-holes and excavation of enlarged subsurface openings without large entry holes. The design of the conveyors is a modification of conventional screw conveyors such that the central screw-shaft and the outer housing or conveyingtube have a degree of bending flexibility, allowing the conveyors to become nonlinear conveying systems that can convey around gentle bends. The central flexible shaft is similar to those used in common tools like a weed whacker, consisting of multiple layers of tightly wound wires around a central wire core. Utilization of compliant components (screw blade or outer wall) increases the robustness of the conveying, allowing an occasional oversized particle to pass hough the conveyor without causing a jam or stoppage

  9. A device for loading coal onto a conveyor

    Energy Technology Data Exchange (ETDEWEB)

    Kartavykh, G.I.; Startsev, V.I.

    1980-04-05

    The device contains sliding bearings mounted in the guides under the chute flight of the conveyor which are hinged to the coulters, and a control jack. In order to increase the effectiveness of the process of loading the coal onto the conveyor, the device is equipped with cleaners that are hinged by one end to the chute flight, and the other ends are mounted to allow for interaction with the coulter, and coulter rotation limiters that are built in the form of chains connected to the sliding bearings, and breakup blades with guides that hold the sliding bearings. The control jack cylinder is connected to the chute flight, while the rod is hinged to the coulter.

  10. Schmitt Trigger with Controllable Hysteresis Using Current Conveyors

    Directory of Open Access Journals (Sweden)

    Jiri Misurec

    2012-07-01

    Full Text Available Active elements working in the current or mixed mode are still attractive for the design of analog functional blocks. The current conveyor (CC was defined already in 1968. This paper deals with hysteresis comparators using second generation current conveyor. The comparator is basically a pulse circuit. In these circuits, the maximum rate of change in the output voltage is required during switching from one state to another. In comparators with operational amplifiers the switching time is given by the slew rate of the operational amplifier used, which is not too high. If a current conveyor is used, the time of switching the comparator gets shorter. The comparator is capable to operate at a higher frequency bands and if it is used, for example, in converters, a higher operating frequency can be reached. The connection of an inverting and a non-inverting comparator with adjustable hysteresis is shown as a practical implementation. Using the AD844, results of experimental measurements are presented that confirm the theoretical  assumptions and the results of computer simulation.

  11. Numerical simulation of dust explosions in pneumatic conveyors

    Science.gov (United States)

    Bielert, U.; Sichel, M.

    Dust conveyors are used in a wide range of industrial applications. Explosions can be transmitted through dust conveyors to different parts of a processing facility and thus can cause a large amount of damage. In order to study the evolution of dust explosions in such conveyors, a numerical model was developed which combines a front tracking method with a solver for the Euler equations. In this model the effects of the chemical reactions and of the flow turbulence were summarized in the turbulent burning velocity of the dust-air mixture. This approach results in a large reduction of the computational effort and thus allows to study the influence of parameter variations. Here results are presented for corn starch-air mixtures. The numerical model was first calibrated by comparison with one set of experimental data. The model was then tested by comparison with different experimental data and the sensitivity of the model parameters is discussed. Finally calculations were performed for different dust concentrations, flow velocities and tube lengths.

  12. Trajectories of soil particles on a hillslope conveyor: Implications for particle age and Be-10 field

    Science.gov (United States)

    Anderson, R. S.

    2015-12-01

    Many geomorphic systems act as conveyor belts onto which material is loaded at a particular rate, and is transported in one direction toward another system that serves as a sink. In general the material will evolve as it travels: it ages, it changes in grain size, it absorbs and releases nutrients, it weathers and it accumulates cosmogenic radionuclides. Here I address the hillslope conveyor. As many geochemical and physical processes are depth-dependent, the depth history of a particle becomes important to know. I calculate soil particle trajectories in the horizontal-depth plane and address three steady state cases, one in which horizontal speeds decline exponentially with depth, a second in which they are uniform with depth, and a third in which horizontal speeds are also uniform but all profile values are vertically well-mixed. Vertical speeds are governed by conservation of mass, which requires that strain rates in the horizontal enact strains rates of opposite sign in the vertical, and by the boundary conditions of zero vertical particle speed at the soil surface and the particle release rate at the saprolite interface. Particle trajectories must become surface-parallel at the surface. Knowledge of soil particle trajectories allows calculation of residence times and concentration profiles of 10Be in the soil. In all steady cases, the particle age and 10Be structure are uniform with distance from the divide. When significant vertical gradients in horizontal speed occur, the vertical profiles of particle age and 10Be concentration are dominated by the depth scale of the transport process. In unmixed cases, the particle age and 10Be concentration in near-surface samples can greatly exceed the vertically averaged values, reflecting the slowing of vertical speeds as particles approach the surface. Where horizontal speeds vary significantly with depth, the vertically-averaged concentration of 10Be within the soil can significantly under-predict the mean 10Be

  13. An on-belt elemental analyser for the cement industry.

    Science.gov (United States)

    Lim, C S; Tickner, J R; Sowerby, B D; Abernethy, D A; McEwan, A J; Rainey, S; Stevens, R; Manias, C; Retallack, D

    2001-01-01

    On-line control of raw mill feed composition is a key factor in the improved control of cement plants. A new and improved on-conveyor belt elemental analyser for cement raw mill feed based on neutron inelastic scatter and capture techniques has been developed and tested successfully in Adelaide Brighton's Birkenhead cement plant on highly segregated material with a depth range of 100 to 180 mm. Dynamic tests in the plant have shown analyser RMS total errors of 0.49, 0.52, 0.38 and 0.23 wt% (on a loss free basis) for CaO, SiO2, Al2O3 and Fe2O3 respectively, when 10-minute counting periods are used. PMID:11144240

  14. Availability analysis of the main conveyor in the Svea Coal Mine in Norway

    Institute of Scientific and Technical Information of China (English)

    Simon Furuly; Javad Barabady; Abbas Barabadi⇑

    2014-01-01

    Reliability and maintainability of mining industry is more in focus than ever, and the mining systems are becoming more complex and the equipment more expensive to repair or modify. Unplanned failures can result in significant costs, especially when the machinery is hard to repair or spare parts are far away. This paper presents a case study describing a reliability and maintainability analysis of the main conveyor system of the Svea Coal Mine located in Svalbard, Norway. The conveyor system includes several separate conveyors. In this study, the main six conveyors of the whole system were selected for the analysis. The failure and repair data of the conveyors were collected for the whole year of 2010 using maintenance and daily reports. The date was analyzed and the result shows that the availability of six conveyers is 96.44%for one year of operation. However, reliability of these conveyers needs to be improved in order to reduce the number of failures.

  15. An integrated multi-criteria decision-making methodology for conveyor system selection

    Directory of Open Access Journals (Sweden)

    Pairat Jiamruangjarus

    2016-12-01

    Full Text Available Material handling equipment (MHE is important for every industry because it has an effect on the productivity of manufacturing. Conveyor systems are presently one popular type of MHE. This paper presents an integration of the analytic network process (ANP with the benefits, opportunities, costs and risk (BOCR model in order to select the best conveyor system. The proposed model established a network with four merits, six strategies criteria, and twenty six sub-criteria with four alternatives (present, roller conveyor, chain conveyor, and monorail. The ANP is to determine the relative weights of an evaluative criteria and decision alternatives. Therefore, the final ranking of the alternatives are calculated by synthesizing the score of each alternative under BOCR. The results showed that the best alternative under all five methods is the chain conveyor. These research results can be easily applied, adapted and used to improve performance of selecting the conveyer system in small and medium enterprises through large industries.

  16. A CAD/CAM system for operating overburden conveyor bridges

    Energy Technology Data Exchange (ETDEWEB)

    Pause, M.; Nadeborn, H.; Klus, R.

    1988-01-01

    Reviews introduction of computer systems for control of conveyor bridges for overburden removal in GDR brown coal surface mines. Three F 60 high capacity bridges at Welzow, Nochten and Jaenschwalde have been automated since 1978, achieving a 10% increase in annual production. A pilot project of complex automation of a F 45 brige at the Meuro mine was started to fully automate bridge movement according to continuous mine geometrical digital survey data. Hardware employed is the U 5000 control system with various peripheral equipment, the A 5120 office computer and the EC 1040 data processing unit. Automation of the Meuro bridge resulted in an annual economic benefit of 2.8 million Marks. A new, fourth F 60 bridge for which a CAD/CAM system based on the U 5000 and K 1520 computer systems is being developed will begin operation at the Reichwalde mine.

  17. A case study on the formation and evolution of ice supersaturation in the vicinity of a warm conveyor belt’s outflow region

    Directory of Open Access Journals (Sweden)

    P. Spichtinger

    2004-12-01

    Full Text Available A case study is presented on the formation and evolution of an ice-supersaturated region (ISSR that was detected by a radiosonde in NE Germany at 06:00 UTC 29 November 2000. The ISSR was situated in the vicinity of the outflow region of a warm conveyor belt associated with an intense event of cyclogenesis in the eastern North Atlantic. Using ECMWF analyses and trajectory calculations it is determined when the air parcels became supersaturated and later subsaturated again. In the case considered, the state of air parcel supersaturation can last for longer than 24 h. The ISSR was unusually thick: while the mean vertical extension of ISSRs in NE Germany is about 500 m, the one investigated here reached 3 km. The investigated ice-supersaturated region was bordered both vertically and horizontally by strongly subsaturated air. Near the path of the radiosonde the ISSR was probably cloud free, as inferred from METEOSAT infrared images. However, at other locations within the ISSR it is probable that there were cirrus clouds. Relative humidity measurements are used to correct the negative bias of the ECMWF humidity and to construct two-dimensional maps of ice supersaturation over Europe during the considered period. A systematic backward trajectory analysis for the ISSRs on these maps shows that the ISSR air masses themselves experienced only a moderate upward motion during the previous days, whereas parts of the ISSRs were located just above strongly ascending air masses from the boundary layer. This indicates qualitatively that warm conveyor belts associated with mid-latitude cyclogenesis are disturbances that can induce the formation of ISSRs in the upper troposphere. The ISSR maps also lead us to a new perception of ISSRs as large dynamic regions of supersaturated air where cirrus clouds can be embedded at some locations while there is clear air at others.

  18. 输送机非线性动力学的研究及其对动态性能的影响%Study on conveyor non-linear dynamics and its effect on dynamic behavior

    Institute of Scientific and Technical Information of China (English)

    李光布

    2004-01-01

    A conveyor linear system assumption is based on an approximate description of belt mechanics behavior and constant elastic module. It produces analysis errors and improper dynamics simulation in large conveyors. The belt non-linear characteristics based on sag are described and the belt equivalent elastic module expression is deduced. The relationship between belt-equivalent elastic module and elastic module is studied, and their ratio varies from 0. 1 to 1. 0. The non-linear motion equation with a lumped element model is put forward. Its increment equation and numerical solution are built. A dynamics simulation on a conveyor is carried out, mainly to calculate and compare belt speed, acceleration, tension, displacement of gravity take-up and wave period with linear and non-linear models. It shows that the simulation errors between two models vary from 6% to 50%.%输送机线性系统的假设是在胶带力学特性和弹性模量不变的情况下近似提出的. 这种假设会使大型输送机产生理论误差和不正确的动力学仿真结果. 本文分析了基于胶带悬垂度的非线性特性, 推导了等效弹性模量的表达式, 研究了胶带等效弹性模量和弹性模量之间的关系, 并发现两者的比值在0. 1~1. 0之间变化. 提出了输送机有限单元模型的非线性运动方程及其增量方程和数值解法. 通过对一输送机动态特性的仿真分析, 发现用线性和非线性2种模型, 它们动态参数(如带速, 胶带加速度, 张力以及重锤位移和张力波速)的计算误差介于6%~50% 之间.

  19. [Effect of local sustained stress on general oxygen consumption in belt conveyer workers].

    Science.gov (United States)

    Nakamura, E; Taguchi, S; Fujiki, Y; Kanetaka, A; Nagata, H

    1984-09-01

    The modern mechanization and rationalization of production procedures have recently reduced the intensity of work in most factories. However, it has been pointed out that monotonous inactive work and/or co-operative work can in some sense impose stronger mental and physical stresses which may induce ill health in workers. In this study, assuming the assembly and adjustment of videotape-recorders on a belt conveyor to be representative of monotonous inactive and co-operative work, changes in oxygen consumption, heart rate, blood pressure, body temperature, critical flicker fusion and subjective symptoms of fatigue throughout a workday have been followed for six female workers engaged in this type of work. The main results obtained were as follows: The average oxygen consumption of six workers was 230 ml/min, almost unchanged during the work. The belt conveyor work indicated the metabolic rate of 0.3 in terms of relative metabolic rate. The net daily energy expenditure due to the work was only about 100 kcal. The average heart rate during assembly and adjustment were respectively, about 1.4 and 1.2 times the average heart rate at rest. The blood pressure and the rate of oxygen removal increased slightly as the work progressed in assembly work, but did not increase at all in adjustment work. The critical flicker fusion and body temperature showed little change during the work.

  20. Simulation and Analysis of Second Generation Current Conveyor using 0.18 µm CMOS Technology

    OpenAIRE

    Prachi Parikh

    2014-01-01

    A wide bandwidth CMOS realization of high performance dual output second generation (CCII±) current conveyor is presented. second generation current conveyor has the advantages of a wide current and voltage bandwidths, controlled intrinsic resistances at port X, Y and Z. SPICE simulation show that the current and voltage bandwidths are respectively 2.05 GHz and 4.3 GHz for a control current of 26 µA. CCII± is a useful building block for analog circuits, especially for applicati...

  1. Designing a system for measuring the flow of material transported on belts using ultrasonic sensors

    Science.gov (United States)

    Mihuţ, N. M.

    2015-11-01

    Excavation tailings (scraping) and extracting the useful (lignite) in surface mine pits in Mining Basin Oltenia is achieved with technological lines of excavation - transport - dump of high productivity. A correlation of working capacity of the main components of technological lines (motor rotor, high capacity transport, car dumps) is necessary for economic reasons on electricity consumption. To achieve experience in the process was chosen excavator SRS 1400 from South Jilt career in the CET Turceni. The question of coal excavated volume has a great importance in the mine pits. At the excavation is desired a density estimate for each machine production tracking, cost estimation and tracking product unit profitability of each band on various sections zones. Permanent display size excavated volume snapshots in the excavator's cabin permits to track tape loading, eliminating unproductive times and information management to determine profitability. Another important requirement is closing the loop of the machine drive system of an excavator for a uniform deposition of carbon on the strip, thus achieving automatic control of the loading belt. Such equipment is important for the system dispatching in surface mine pits. Through a system of three ultrasound transducers to determine the smart instant of coal excavated section which, coupled with the tape speed, integrated over time will determine the amount of excavated coal. The basis of the system developed is a device for determining the volume and quantity of coal excavated acting on the march and optimize the system speed excavator working order. The device is designed primarily following the careers of lignite production: rotor excavators, rubber conveyor belts and dump facilities. Newly developed system aims to achieve the following determines: the optimum energy excavation depending on the nature of excavated material - lignite, shale, clay, etc., economic times to use the excavator bucket teeth rotor, energy

  2. Lap belt injuries in children.

    LENUS (Irish Health Repository)

    McGrath, N

    2010-07-01

    The use of adult seat belts without booster seats in young children may lead to severe abdominal, lumbar or cervical spine and head and neck injuries. We describe four characteristic cases of lap belt injuries presenting to a tertiary children\\'s hospital over the past year in addition to a review of the current literature. These four cases of spinal cord injury, resulting in significant long-term morbidity in the two survivors and death in one child, arose as a result of lap belt injury. These complex injuries are caused by rapid deceleration characteristic of high impact crashes, resulting in sudden flexion of the upper body around the fixed lap belt, and consequent compression of the abdominal viscera between the lap belt and spine. This report highlights the dangers of using lap belts only without shoulder straps. Age-appropriate child restraint in cars will prevent these injuries.

  3. Design and calculation of Scew Conveyor%基于螺旋输送机的设计计算

    Institute of Scientific and Technical Information of China (English)

    李彦

    2014-01-01

    此螺旋输送机的设计主要用于饲料的传送,根据给定的输送量以及物料特性分别进行叶片用料实形、螺旋直径、螺旋转速等主要参数的设计计算。传动部分采用电动机带动皮带,皮带带动一级减速器、减速器连接机体的传动方式。根据计算得出的主要参数选择合适的电动机,从而确定带轮以及减速器的传动比,将主要后续工作引向一级减速器的设计,其中包括主要传动轴的校核、齿轮的选择等计算工作。最后根据计算所得结果整理出安装尺寸以及装配图的绘制。%The screw conveyor is mainly designed to convey feed. Design and calculate the real shape of material, the diame-ter of screw, screw speed and other main parameters of the blade respectively according to the given conveying capacity and ma-terial properties. The transmission part starts with a motor driving belt,and then the transmission belt driving first-level reducer and the connection body of reducer. Select appropriate motor according to the main parameters calculated, and then determine the conveying ratio of belt pulley and reducer. The design of driving main follow-up work to a reducer, includes checking of main transmission shafts the selection of gears and other calculation. Finally, sort out the installation dimensions and draw assembly drawing according to the results calculated.

  4. SLH Timing Belt Powertrain

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, Abe

    2014-04-09

    The main goal of this proposal was to develop and test a novel powertrain solution for the SLH hydroEngine, a low-cost, efficient low-head hydropower technology. Nearly two-thirds of U.S. renewable electricity is produced by hydropower (EIA 2010). According to the U.S. Department of Energy; this amount could be increased by 50% with small hydropower plants, often using already-existing dams (Hall 2004). There are more than 80,000 existing dams, and of these, less than 4% generate power (Blankinship 2009). In addition, there are over 800 irrigation districts in the U.S., many with multiple, non-power, low-head drops. These existing, non-power dams and irrigation drops could be retrofitted to produce distributed, baseload, renewable energy with appropriate technology. The problem is that most existing dams are low-head, or less than 30 feet in height (Ragon 2009). Only about 2% of the available low-head hydropower resource in the U.S. has been developed, leaving more than 70 GW of annual mean potential low-head capacity untapped (Hall 2004). Natel Energy, Inc. is developing a low-head hydropower turbine that operates efficiently at heads less than 6 meters and is cost-effective for deployment across multiple low-head structures. Because of the unique racetrack-like path taken by the prime-movers in the SLH, a flexible powertrain is required. Historically, the only viable technological solution was roller chain. Despite the having the ability to easily attach blades, roller chain is characterized by significant drawbacks, including high cost, wear, and vibration from chordal action. Advanced carbon- fiber-reinforced timing belts have been recently developed which, coupled with a novel belt attachment system developed by Natel Energy, result in a large reduction in moving parts, reduced mass and cost, and elimination of chordal action for increased fatigue life. The work done in this project affirmatively addressed each of the following 3 major uncertainties concerning

  5. Geography of the asteroid belt

    Science.gov (United States)

    Zellner, B. H.

    1978-01-01

    The CSM classification serves as the starting point on the geography of the asteroid belt. Raw data on asteroid types are corrected for observational biases (against dark objects, for instance) to derive the distribution of types throughout the belt. Recent work on family members indicates that dynamical families have a true physical relationship, presumably indicating common origin in the breakup of a parent asteroid.

  6. Dynamic Conveyor Tracking for Delta Robot%基于 Delta 并联机器人的传送带动态跟踪

    Institute of Scientific and Technical Information of China (English)

    邓明星; 刘冠峰; 张国英

    2015-01-01

    Delta并联机器人是最典型的空间三自由度移动的并联机构,其在3C电子产品行业、食品包装行业、生物制药行业均得到了广泛的应用。主要以Delta并联机器人为研究对象,通过视觉系统定位物体的位姿,再结合传送带编码器的位置反馈信息,计算出物体在机器人坐标系下面的实时位姿。实验结果表明,机器人在位置模式下,通过改进后的PID算法,能预测传送带上物体的位姿,并实时调整自身移动速度和末端位姿来跟踪传送带上的物体,最终实现对目标的动态跟踪抓取。%The Delta parallel robot is the most typical space moving parallel mechanism which has three degree of freedom .It is widely used in 3C electronic products ,food packaging and pharmaceutical packaging .In this paper ,Delta parallel robot was taken as study objective ,the pose of the object was got by machine vision system ,which was coupled with the position feedback information of conveyor encoder ,then the object’s real-time pose in the robot coordinate was calculated .The experiment results show that the robot can predict the object’s pose on the conveyor belt ,adjust its speed and pose by the improved PID algorithm in the position mode ,realize the dynamic tracking fetch of the target finally .

  7. Voltage-Controlled Square/Triangular Wave Generator with Current Conveyors and Switching Diodes

    Directory of Open Access Journals (Sweden)

    Martin Janecek

    2012-12-01

    Full Text Available A novel relaxation oscillator based on integrating the diode-switched currents and Schmitt trigger is presented. It is derived from a known circuit with operational amplifiers where these active elements were replaced by current conveyors. The circuit employs only grounded resistances and capacitance and is suitable for high frequency square and triangular signal generation. Its frequency can be linearly and accurately controlled by voltage that is applied to a high-impedance input. Computer simulation with a model of a manufactured conveyor prototype verifies theoretic assumptions.

  8. Some aspects of the characteristics of vertical screw conveyors for granular material

    NARCIS (Netherlands)

    Rademacher, F.J.C.

    1974-01-01

    A theory has been developed, based on a physical model, to describe the behaviour of non-cohesive granular material inside a vertical screw conveyor. By use of this theory, relationships have been derived between dimensionless numbers for capacity, power consumption and efficiency. These relationshi

  9. Theoretical and experimental investigation on optimization of a non-contact air conveyor

    Institute of Scientific and Technical Information of China (English)

    钟伟; 黎鑫; 陶国良; 路波; 香川利春

    2016-01-01

    Air film conveyors equipped with porous pads have been developed to bring the liquid crystal display (LCD) into a non-contact state during transportation process. In this work, a theoretical model including flow property of porous media and Reynolds equation is established within a representative region in order to optimize the design parameters of a partial porous air conveyor. With the theoretical model, an optimization method using nondominated sorting genetic algorithm – II (NSGA-II) is applied for a two-objective optimization to achieve a minimum air consumption and maximum load capacity. Three Pareto-optimal solutions are selected to analyze the influence of each parameter on the characteristics of the air conveyor, and the results indicate that the position of the porous pads has the most significant impact on the performance and of course must be determined with care. Furthermore, experimental results in terms of the supporting force versus gap clearance show that the optimized air conveyor can greatly improve the load capacity over the normal one, indicating that the optimization method is applicable for practical use.

  10. Kuiper Belts Around Nearby Stars

    CERN Document Server

    Nilsson, R; Brandeker, A; Olofsson, G; Pilbratt, G L; Risacher, C; Rodmann, J; Augereau, J -C; Bergman, P; Eiroa, C; Fridlund, M; Thébault, P; White, G J

    2010-01-01

    In order to detect and characterise cold extended circumstellar dust originating from collisions of planetesimal bodies in disks, belts, or rings at Kuiper-Belt distances (30--50\\,AU or beyond) sensitive submillimetre observations are essential. Measurements of the flux densities at these wavelengths will extend existing IR photometry and permit more detailed modelling of the Rayleigh-Jeans tail of the disks spectral energy distribution (SED), effectively constraining dust properties and disk extensions. By observing stars spanning from a few up to several hundred Myr, the evolution of debris disks during crucial phases of planet formation can be studied. // We have performed 870\\,$\\mu$m observations of 22 exo-Kuiper-Belt candidates, as part of a Large Programme with the LABOCA bolometer at the APEX telescope. Dust masses (or upper limits) were calculated from integrated 870\\,$\\mu$m fluxes, and fits to the SED of detected sources revealed the fractional dust luminosities $f_{\\mathrm{dust}}$, dust temperatures...

  11. Current Conveyor All-Pass Sections: Brief Review and Novel Solution

    Directory of Open Access Journals (Sweden)

    Sudhanshu Maheshwari

    2013-01-01

    Full Text Available This study relates to the review of an important analog electronic function in form of all-pass filter’s realization using assorted current conveyor types and their relative performances, which resulted in a novel solution based on a new proposed active element. The study encompasses notable proposals during last the decade or more, and provides a platform for a broader future survey on the topic for enhancing the knowledge penetration amongst the researchers in the specified field. A new active element named EXCCII (Extra-X second generation current conveyor with buffered output is found in the study along with its use in a new first-order all-pass section, with possible realization using commercially available IC (AD-844 and results.

  12. Analytical model of load stream transformation in conveyor-hopper haulage systems in coal mines

    Energy Technology Data Exchange (ETDEWEB)

    Kreimer, E.L. (DonUGI (USSR))

    1989-11-01

    Haulage of coal and mine stones by a system of conveyors and coal hoppers is treated as a stochastic process. Stream of coal flowing from working faces by a conveyor-hopper system is characterized by the G{sub 6} vector consisting of 6 linearly independent parameters: a coefficient of load stream advance, mathematical expectation, standard deviation, maximum coal stream, correlation period of coal stream, mathematical expectation of the length of coal supply periods. An analytical model which permits the G{sub 6} vector to be calculated at any stage of coal haulage system is developed. Analyses show that a coal haulage system is accurately described by a multistage Markov process. 10 refs.

  13. French experience in seat belt use.

    NARCIS (Netherlands)

    Lassarre, S. & Page, Y.

    1992-01-01

    This paper concerns the French experience in seat belt use. As well as the seat belt regulations, the strategies employed to reinforce the wearing of seat belts by using information and encouragement campaigns and checks by the police and gendarmerie are described here along with their timetables an

  14. 皮带机故障分析及处理%Failures Analysis and Disposal on Belt Conveyer

    Institute of Scientific and Technical Information of China (English)

    胡文举

    2012-01-01

    The belt conveyor is a type of material conveying machine. It is widely used in salt field because of its advantages of large transportation capacity, simple structure, easy maintaining , low cost, general purpose and so on. The reasons for failures and the methods for disposal are analyzed in the article.%皮带机作为运输机械,以其输送量大、结构简单、维护方便、成本低、通用性强等优点,在盐场应用相当广泛.文章分析了皮带机常见故障产生的原因及其处理方法.

  15. Development of movable fully-mechanized belt recovery device in mine%煤矿移动式综掘皮带回收装置研制

    Institute of Scientific and Technical Information of China (English)

    董友泉

    2014-01-01

    煤矿综采工作面顺槽综掘施工中,综掘机配套皮带运输机的皮带回收卷带是经常性的工作,关系到综掘掘进工效和安全施工。本装置利用液压泵站为收卷带装置动力源,可以远端控制,实现收卷带机械化,比传统的收带卷带的办法提高了效率和安全性,比目前的电动卷放带装置便捷可靠。%In crossheading fullyGmechanized construction in working face of mine,the belt winding of belt conveyor is regular work,which is related to the fully mechanized excavation effiG ciency and safety in construction.Through a hydraulic pump station,the device collects the powG er for belt winding,which realizes the remote control and belt winding mechanization,and aG chieves more efficiency and safety than the original winding method;it is more convenient and reG liable than the present electric windingGunwinding device.

  16. Use of computational fluid dynamics simulations for design of a pretreatment screw conveyor reactor.

    Science.gov (United States)

    Berson, R Eric; Hanley, Thomas R

    2005-01-01

    Computational fluid dynamics simulations were employed to compare performance of various designs of a pretreatment screw conveyor reactor. The reactor consisted of a vertical screw used to create cross flow between the upward conveying solids and the downward flow of acid. Simulations were performed with the original screw design and a modified design in which the upper flights of the screw were removed. Results of the simulations show visually that the modified design provided favorable plug flow behavior within the reactor. Pressure drop across the length of the reactor without the upper screws in place was predicted by the simulations to be 5 vs 40 kPa for the original design.

  17. Design Considerations for CMOS Current Mode Operational Amplifiers and Current Conveyors

    DEFF Research Database (Denmark)

    Bruun, Erik

    AB conveyor implementations to implementations based on purely digital circuit structures and on more complex analog subsystems such as a voltage mode opamp with feedback to provide a voltage follower action. An important by-product of the investigation of current mode structures is the definition...... constraints into account - the type of opamp providing the highest bandwidth potential is the 'native' opamp type of the feedback system. For instance, if the feedback amplifier system is a transimpedance system (current input, voltage output) the highest bandwidth can be achieved by selecting...

  18. Movement analysis on steel wire rope of continuous conveyor with disc-tube assembly

    Institute of Scientific and Technical Information of China (English)

    LUAN Li-jun; SHI Shu-lin; REN Li-yi

    2004-01-01

    The steel wire rope of continuous conveyor with disc-tube assembly is droved by the driving wheel. When the driving wheel rotates, the gear is combined to the connection disc in turn, promoting the connection disc to move in succession. Turning the whirling torque of driving wheel into the straight-line traction force. When the steel wire rope is winded by the driving wheel some winded along the circumference, others winded along the straight line. Used motion subject law, this article analyses the change of the velocity and the acceleration of the steel wire rope in the straight movement, and observe the mathematics' model of velocity and acceleration.

  19. Event Driven Control of Vibratory Conveyors Operating on the Frahm's Eliminator Basis

    Directory of Open Access Journals (Sweden)

    Klemiato M.

    2015-04-01

    Full Text Available The new, original control method of the vibratory conveyor operating on the Frahm's dynamic eliminator basis, is presented in the paper. The proposed method is based on the application of the control of the feed-forward controler, together with the events detection based on the generalised likelihood ratio (GLR algorithm. Such approach leads to the controller intervention only when it is justified by the current process situation, (e.g. in case of an essential change of the feed mass to enable the stable machine operations and to limit transient states. The results are presented in a form of numerical simulations.

  20. Synchronous and Cogged Fan Belt Performance Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Cutler, D.; Dean, J.; Acosta, J.

    2014-02-01

    The GSA Regional GPG Team commissioned the National Renewable Energy Laboratory (NREL) to perform monitoring of cogged V-belts and synchronous belts on both a constant volume and a variable air volume fan at the Byron G. Rodgers Federal Building and U.S. Courthouse in Denver, Colorado. These motor/fan combinations were tested with their original, standard V-belts (appropriately tensioned by an operation and maintenance professional) to obtain a baseline for standard operation. They were then switched to the cogged V-belts, and finally to synchronous belts. The power consumption by the motor was normalized for both fan speed and air density changes. This was necessary to ensure that the power readings were not influenced by a change in rotational fan speed or by the power required to push denser air. Finally, energy savings and operation and maintenance savings were compiled into an economic life-cycle cost analysis of the different belt options.

  1. Surveying the face head advance rate and the face conveyor position. Ueberwachung des Strebfrontverlaufs und der Lage von Strebfoerdermitteln

    Energy Technology Data Exchange (ETDEWEB)

    1975-01-01

    For a constant monitoring of the face work and the position of the face conveyor, continuous surveying of the conveyor systems is required. This publication of the Steinkohlenbergbauverein describes two well-established surveying techniques using either a folding rule or a tape measure or advance rate meter. The latter is described with regard to its design and functions. Both methods are quasisteady methods which can be carried out by the working staff or by the foreman without disturbing operations and with hardly any loss of time. (MOS).

  2. 一种螺旋输送机的改进设计%An Improved Design of the Screw Conveyor

    Institute of Scientific and Technical Information of China (English)

    左章华

    2014-01-01

    通过一次闲置的螺旋输送机改造过程,叙述了螺旋输送机改造中需要注意的几个相关事项,并对螺旋输送机现场改造中涉及到的问题提出了相应的解决办法。%In this paper ,through the transformation process of an idle screw conveyor ,describes several re-lated issues that need attention on the transformation of the screw conveyor , and on-site issues related to this transformation,here advance a corresponding solution .

  3. NONLINEAR DYNAMIC BEHAVIOR OF VISCOELATIC TRANSMISSION BELT

    Institute of Scientific and Technical Information of China (English)

    Li Yinghui; Gao Qing; Jian Kailin; Yin Xuegang

    2003-01-01

    The nonlinear dynamic responses of viscoelastic axially transmission belts are investigated and the Kelvin viscoelastic differential constitutive model is employed to characterize the material property of belts. The generalized equation of motion is obtained for a viscoelatic axially transmission belts with geometric nonlinearity first, and then is reduced to be a set of second-order nonlinear ordinary differential equations by applying Galerkin's method. Finally, the effects of viscosity parameter and elastic parameter and the moving velocity of the belts on the transient responses are investigated by the research of digital simulation.

  4. Computational fluid dynamics simulation and redesign of a screw conveyor reactor.

    Science.gov (United States)

    Wan, Yinkun; Hanley, Thomas R

    2004-01-01

    National Renewable Energy Laboratory (NREL) designed a shrinking-bed reactor to maintain a constant bulk packing density of cellulosic biomass. The high solid-to-liquid ratio in the pretreatment process allows a high sugar yield and avoids the need to flush large volumes of solution through the reactor. To scale up the shrinking-bed reactor, NREL investigated a pilot-scale screw conveyor reactor in which an interrupted flight between screws was employed to mimic the "shrinking-bed" effect. In the experiments with the screw conveyor reactor, overmixing and uneven flow occurred. These phenomena produce negative effects on biomass hydrolysis. The flow behavior inside the reactor was analyzed to allow redesign of the screw to achieve adequate mixing and even flow. In the present study, computational fluid dynamics (CFD) was utilized to simulate the fluid flow in the porous media, and a new screw design was proposed. CFD analysis performed on the redesigned reactor indicated that an even flow pattern was achieved.

  5. Numerical evaluation of turbulence models for dense to dilute gas-solid flows in vertical conveyor

    Institute of Scientific and Technical Information of China (English)

    Salar Azizi; Dariush Mowla; Goodarz Ahmadi

    2012-01-01

    A two-fluid model (TFM) of multiphase flows based on the kinetic theory and small frictional limit boundary condition of granular flow was used to study the behavior of dense to dilute gas-solid flows in vertical pneumatic conveyor.An axisymmetric 2-dimensional,vertical pipe with 5.6 m length and 0.01 m internal diameter was chosen as the computation domain,same to that used for experimentation in the literature.The chosen particles are spherical,of diameter 1.91 mm and density 2500 kg/m3.Turbulence interaction between the gas and particle phases was investigated by Simonin's and Ahmadi's models and their numerical results were validated for dilute to dense conveying of particles.Flow regimes transition and pressure drop were predicted.Voidage and velocity profiles of each phase were calculated in radial direction at different lengths of the conveying pipe.It was found that the voidage has a minimum,and gas and solid velocities have maximum values along the center line of the conveying pipe and pressure drop has a minimum value in transition from dense slugging to dilute stable flow regime.Slug length and pressure fluctuation reduction were predicted with increasing gas velocity,too.It is shown that solid phase turbulence plays a significant role in numerical prediction of hydrodynamics of conveyor and the capability of particles turbulence models depends on tuning parameters of slip-wall boundary condition.

  6. Irradiation process validation in the new conveyor system installed at PISI: special dosimetry

    International Nuclear Information System (INIS)

    Semi Industrial Irradiation Plant (PISI) is a multipurpose facility which uses 60Co sources to treat different products with numerous purposes, such as sterilization of medical devices, pharmaceutical and veterinarian products; control of pathogenic microorganisms, shelf-life extension and insect disinfestation of food, among others. In order to achieve the desired effect, the product is carried inside the irradiation chamber by means of a conveyor system, and it is exposed to radiation following a pre-established path. The recent installation of a new conveyor system at PISI demands the execution of a thorough validation programme. The scope of this presentation is to describe the dose mapping tasks that will be performed in order to characterize the irradiator and its new conveyor system with respect to distribution and variability of dose, complying with international standards on good irradiation practices. Information about the distribution and variability of dose in a product irradiated under defined conditions will allow the obtaining of process parameters which will conform the process specifications in future routine irradiations. The initial stages of the Validation Programme are the Installation Qualification, the Operational Qualification (OQ) and the Performance Qualification (PQ). To accomplish the IQ diverse tests are being carried out at PISI in order to verify that the system has been installed and is operating according to its technical specifications. Both OQ and PQ require dose mapping on simulated and real product, respectively. Dose mapping consists on placing dosimeters on a process load of homogeneous material -under certain irradiator and process parameters- according to a three-dimensional pre-established placement pattern. Since the replacement of the conveyor system introduces a significant modification in the source-to-product geometry, therefore in dose distribution, there is no reference dosimetry data available, so a more exhaustive

  7. Apparatus for heat treating plastic belts

    Science.gov (United States)

    Topits, A., Jr.

    1975-01-01

    Apparatus performs programed rotating, stretching/shrinking and heat treatment necessary to fabrication of high-performance plastic belts. Belts can be treated in lengths varying from 7 to 48 in., in widths up to 1 in., and in thicknesses up to approximately 0.003 in.

  8. Understanding Quaternions and the Dirac Belt Trick

    Science.gov (United States)

    Staley, Mark

    2010-01-01

    The Dirac belt trick is often employed in physics classrooms to show that a 2n rotation is not topologically equivalent to the absence of rotation whereas a 4n rotation is, mirroring a key property of quaternions and their isomorphic cousins, spinors. The belt trick can leave the student wondering if a real understanding of quaternions and spinors…

  9. Parameters affecting seat belt use in Greece.

    Science.gov (United States)

    Yannis, G; Laiou, A; Vardaki, S; Papadimitriou, E; Dragomanovits, A; Kanellaidis, G

    2011-09-01

    The objective of this research is the exploration of seat belt use in Greece and particularly the identification of the parameters affecting seat belt use in Greece. A national field survey was conducted for the analytical recording of seat belt use. A binary logistic regression model was developed, and the impact of each parameter on seat belt use in Greece was quantified. Parameters included in the model concern characteristics of car occupants (gender, age and position in the car), the type of the car and the type of the road network. The data collection revealed that in Greece, the non-use of seat belt on the urban road network was higher than on the national and rural road network and young and older men use seat belts the least. The developed model showed that travelling on a national road is negative for not wearing the seat belt. Finally, the variable with the highest impact on not wearing a seat belt is being a passenger on the back seats. PMID:21452095

  10. Radiation belt dynamics during solar minimum

    Energy Technology Data Exchange (ETDEWEB)

    Gussenhoven, M.S.; Mullen, E.G. (Geophysics Lab., Air Force Systems Command, Hanscom AFB, MA (US)); Holeman, E. (Physics Dept., Boston College, Chestnut Hill, MA (US))

    1989-12-01

    Two types of temporal variation in the radiation belts are studied using low altitude data taken onboard the DMSP F7 satellite: those associated with the solar cycle and those associated with large magnetic storm effects. Over a three-year period from 1984 to 1987 and encompassing solar minimum, the protons in the heart of the inner belt increased at a rate of approximately 6% per year. Over the same period, outer zone electron enhancements declined both in number and peak intensity. During the large magnetic storm of February 1986, following the period of peak ring current intensity, a second proton belt with energies up to 50 MeV was found at magnetic latitudes between 45{degrees} and 55{degrees}. The belt lasted for more than 100 days. The slot region between the inner and outer electron belts collapsed by the merging of the two populations and did not reform for 40 days.

  11. Shaft conveyor

    International Nuclear Information System (INIS)

    This device for the conveyance along shafts of radioactive waste usually enclosed in metal barrels is based on a single mechanism which has proved successful in mining. The rope-hauled conveying vessel runs on 4 rollers above and below between guide rails on a vertical shaft and in its highest position is above ground in front of a loading device. A motor driven rolling table moves a standing barrel with the material being conveyed to in front of the loading opening of the conveying vessel, where a lever prevents further movement until the conveying vessel is in exactly the right position. After retraction of the interlocking lever, the rolling table moves the material being conveyed on the further rollers in a framework in the conveying vessel. This roller framework with its slightly transverse position leans the transport barrel against the vessel rear wall during transport. In the deep position of the conveying vessel the barrel moving downwards runs off the roller framework due to a slight tilting movement and falls into the cavern. Levers which can rotate around vertical axes grip the barrel in the conveying vessel and secure its position during transport. In the loading and unloading positions, i.e. in the highest and lowest position of the conveying vessel in the shaft, projecting rollers run on the back of the conveying basket on solid control curve paths. Rods connected to the rollers move the stop lever in the conveying vessel back against spring tensions. A barrel can be tipped out below or a new barrel can be loaded above. The tipping of he roller framework (at the lower end of the shaft) is controlled in the same way. The rolling table of the loading device automatically matches its height to the roller framework in the conveying vessel. A moving arm with contact shoe follows the standing barrel in the conveying vessel and checks its correct position. It takes over its task if the rolling table fails. (ER)

  12. The Gould's Belt distance survey

    CERN Document Server

    Loinard, L; Torres, R M; Dzib, S; Rodriguez, L F; Boden, A F

    2011-01-01

    Very Long Baseline Interferometry (VLBI) observations can provide the position of compact radio sources with an accuracy of order 50 micro-arcseconds. This is sufficient to measure the trigonometric parallax and proper motions of any object within 500 pc of the Sun to better than a few percent. Because they are magnetically active, young stars are often associated with compact radio emission detectable using VLBI techniques. Here we will show how VLBI observations have already constrained the distance to the most often studied nearby regions of star-formation (Taurus, Ophiuchus, Orion, etc.) and have started to provide information on their internal structure and kinematics. We will then briefly describe a large project (called The Gould's Belt Distance Survey) designed to provide a detailed view of star-formation in the Solar neighborhood using VLBI observations.

  13. Binaries in the Kuiper Belt

    CERN Document Server

    Noll, K S; Chiang, E I; Margot, J L; Kern, S D; Noll, Keith S.; Grundy, William M.; Chiang, Eugene I.; Margot, Jean-Luc; Kern, Susan D.

    2007-01-01

    Binaries have played a crucial role many times in the history of modern astronomy and are doing so again in the rapidly evolving exploration of the Kuiper Belt. The large fraction of transneptunian objects that are binary or multiple, 48 such systems are now known, has been an unanticipated windfall. Separations and relative magnitudes measured in discovery images give important information on the statistical properties of the binary population that can be related to competing models of binary formation. Orbits, derived for 13 systems, provide a determination of the system mass. Masses can be used to derive densities and albedos when an independent size measurement is available. Angular momenta and relative sizes of the majority of binaries are consistent with formation by dynamical capture. The small satellites of the largest transneptunian objects, in contrast, are more likely formed from collisions. Correlations of the fraction of binaries with different dynamical populations or with other physical variabl...

  14. 变频控制在双向双驱皮带输送机中的应用%Applicationin in Dual Driven Belt Convey of Frequency Conversion Control

    Institute of Scientific and Technical Information of China (English)

    钟开虎

    2015-01-01

    通过变频、PLC 控制方式,保证了皮带输送机两端电机可靠同步运行,根据生产需要,皮带输送机可两端出料。采用变频控制双向双驱皮带输送机,最大限度地发挥了散货码头卸船机作业效率,同时也达到了节能和有效降低生产成本的目的,提高了企业经济效益。%In the control method of inverter and PLC,we ensure the reliable synchronization of both ends in the belt conveyor motor running.Acording to production needs,we have found the usage on both sides of the material keeps frequency conversion control of dual driven belt conveyor,unloader for bulk cargo in operation efficiency.So,we have achieved the objective of energy saving to reduce production costs and improve the economic efficiency of enterprises.

  15. FLUID-BASED SIMULATION APPROACH FOR HIGH VOLUME CONVEYOR TRANSPORTATION SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    Ying WANG; Chen ZHOU

    2004-01-01

    High volume conveyor systems in distribution centers have very large footprint and can handle large volumes and hold thousands of items. Traditional discrete-event cell-based approach to simulate such networks becomes computationally challenging. An alternative approach, in which the traffic is represented by segments of fluid flow of different density instead of individual packages, is presented in this paper to address this challenge. The proposed fluid-based simulation approach is developed using a Hybrid Petri Nets framework. The underlying model is a combination of an extension of a Batches Petri Nets (BPN) and a Stochastic Petri Nets (SPN). The extensions are in the inclusion of random elements and relaxation of certain structural constraints. Some adaptations are also made to fit the target system modeling. The approach is presented with an example.

  16. Seat belt use law in developing countries

    Institute of Scientific and Technical Information of China (English)

    SangWanLee

    1999-01-01

    Objective:To highlight the way to successful implementation of mandantory seat belt use law in developing countries particulary where have significant increase in number or cars and subsequent increase in car occupant casualties.Methods:Literatures concerning seat belt use were reviewed and experiences of the world.Satisfactory or not,investigated.It summed up general aspects of seat belt use as well as benefits,attitude toward legislation and measures to enhance the usage.Results:Seat belt use has been proven and stood time tested as the most effective means to protect car occupants from road crash injuries.It appears to be arduous to achieve the golal of seat belt use law in developing countries. but possible via strategies appropriately leading to legislation and promotion of the belt usage.Conclusions:It is prime necessity for the government authorities to recognize the importance of seat belt use.There needs an organizational structure composed of relevant professional from both private and government sectors which is able to carry out every steps toward successful legislation and implementation:education,publicity,enforcement,evaluation and dissemination of the law's benefits.

  17. DYNAMIC RESPONSES OF VISCOELASTIC AXIALLY MOVING BELT

    Institute of Scientific and Technical Information of China (English)

    李映辉; 高庆; 蹇开林; 殷学纲

    2003-01-01

    Based on the Kelvin viscoelastic differential constitutive law and the motion equation of the axially moving belt, the nonlinear dynamic model of the viscoelastic axial moving belt was established. And then it was reduced to be a linear differential system which the analytical solutions with a constant transport velocity and with a harmonically varying transport velocity were obtained by applying Lie group transformations. According to the nonlinear dynamic model, the effects of material parameters and the steady-state velocity and the perturbed axial velocity of the belt on the dynamic responses of the belts were investigated by the research of digital simulation. The result shows: 1 ) The nonlinear vibration frequency of the belt will become small when the relocity of the belt increases. 2 ) Increasing the value of viscosity or decreasing the value of elasticity leads to a deceasing in vibration frequencies. 3 ) The most effects of the transverse amplitudes come from the frequency of the perturbed velocity when the belt moves with harmonic velocity.

  18. From transmission error measurement to Pulley-Belt slip determination in serpentine belt drives: influence of tensioner and belt characteristics

    OpenAIRE

    Manin, Lionel; Michon, Guilhem; Rémond, Didier; Dufour, Regis

    2007-01-01

    Serpentine belt drives are often used in front end accessory drive of automotive engine. The accessories resistant torques are getting higher within new technological innovations as stater-alternator, and belt transmissions are always asked for higher capacity. Two kind of tensioners are used to maintain minimum tension that insure power transmission and minimize slip: dry friction or hydraulic tensioners. An experimental device and a specific transmission error measurement method have been u...

  19. Comprehensive Assessment of SPJ-800 Belt Conveyor%SPJ-800型带式输送机的综合评定

    Institute of Scientific and Technical Information of China (English)

    杜志远

    2011-01-01

    经对SPJ-800型带式输送机的综合评定,得出结论:SPJ-800型带式输送机B=800 nun,V=1.6 m/s,N=2×37 kW,L=370 β尹=2.50,Q=26°,Q-=260/h,满足生产要求;输送带选用PVG800S阻燃抗静电带,额定拉断力Sn=0.8×10(6)N,满足强度要求.

  20. 传输带时钟同步的量子测量原理%The Quantum Measurement of the Conveyor-belt Clock Synchronization

    Institute of Scientific and Technical Information of China (English)

    王兆华

    2012-01-01

    时钟同步技术不管在民用生活中,还是在军事通信中都起着非常重要的作用.但是,现实中并不存在绝对同步的时钟,所以,测量两地时钟的同步性,是全世界国家所关心和研究的重要课题.在这样的背景下,提出一种传输带时钟同步的方法,此方法并不需要交换信号的传输时间;并基于脉冲纠缠双光子的量子相干性,给出了一种时钟同步的光学实验方案,此方案对介质色散具有很强的扼制效应.%The clock synchronization both in daily life, or in the military communications has a very important significance. But in fact, there is no absolute accurate clock, also there is no absolute synchronous clock. So, it is the national concern and research topic for the whole world to measure the synchronism of the two clock. In such background, a protocol for synchronizing distant clocks is proposed that does not rely on the arrival times of the signals which are exchanged. An optical implementation based on coherent-state pulses is described. This protocol is not limited by any dispersion.

  1. 普茨迈斯特皮带机"挑战"沙特最大港口%Putzmeister Belt Conveyor "Challenging" the Biggest Port in Saudi

    Institute of Scientific and Technical Information of China (English)

    杨朔

    2010-01-01

    @@ 吉达港(Jeddah Port)是中东地区历史最悠久的港口之一,已有1300多年的历史,它是世界第28位最繁忙港口,承担了沙特绝大部分的海运工作,是沙特最大的港口.中国港湾沙特阿拉伯工程有限公司从激烈的国际竞争中脱颖而出,承揽了合同金额2.32亿美元的吉达港集装箱码头扩建工程,该工程内容主要包括:建设2个集装箱码头,3个补给码头以及450万方吹填,建设工期22个月.

  2. Application of SVG in Power Supply System of Port Belt Conveyor%港口皮带机系统SVG动态补偿方案

    Institute of Scientific and Technical Information of China (English)

    孙中旺; 靳立开

    2013-01-01

    Frequency converter devices are widely used to port bulk system to improve the reliability and efficiency. It greatly improves the power factor of equipment, reduces the line loss and voltage drop and the demand for voltage regulation device. But the usage of power electronic converter causes that the system is very sensitive to power quality, harmonic content is over-proof and directly, which affect the normal operation and use of the equipment. In order to better solve the harmonic produced by a large number of electronic current transformer equipment, improve power quality, based on Huanghua Port Phase III Pro-ject, of which the SVG is extensively used on equipment in 6 kV substation. Through the reactive power and harmonic com-pensation, harmonic can reduce reactive power loss and avoid a bigger loss, and improve the utilization rate of electrical e-quipment to improve the injection equipment per unit time of active power, the efficiency is greatly increased and the energy saving effect is remarkable.%港口散货系统为提高系统的可靠性和效率而广泛使用电力电子变流器。这虽然大大提高了设备的功率因数,降低了线路损耗和电压降落,减少了对电压调节设备的需求。但是大量电力电子变流器的使用,导致系统电能质量非常敏感,谐波含量超标,直接影响了设备的正常运行和使用。为了更好地解决大量电子变流设备所产生的谐波,提高电能质量,以三期工程为背景在6 kV变电所内大量使用了SVG设备,通过无功及谐波补偿,不仅减少无功损耗,避免谐波造成更大损耗,还可以提高电气设备利用率,提高单位时间内注入设备的有功功率,工作效率大大提高,节能降耗的效果显著。

  3. Application of microprocessing techniques to belt-conveyors%微处理技术在胶带输送机上的应用

    Institute of Scientific and Technical Information of China (English)

    赵宏志

    1993-01-01

    @@ 可编程序控制器(简称PLC)在工业自动控制上的应用越来越广泛,它不仅可以替代繁锁的继电器逻辑系统,提高安全可靠性,而且还能进行数字运算和高速计数等,从而大大提高了自动控制水平,也为系统功能的变更提供了方便.

  4. 主斜井带式输送机提能改造方法探讨%Investigate Method to Reform Lifting Capacity of Main Slant Belt Conveyor

    Institute of Scientific and Technical Information of China (English)

    王建州

    2014-01-01

    通过分析现有主斜井能力提升改造技术各自的优缺点.探讨一种线摩擦驱动的提能改造方法,在主斜井带式输送机上坡段合适的位置加设一套线摩擦驱动带式输送机,给出了选型方法确定线摩擦机的具体位置、长度、功率等,为用户提供借鉴.

  5. The Compositional Structure of the Asteroid Belt

    CERN Document Server

    DeMeo, Francesca E; Walsh, Kevin J; Chapman, Clark R; Binzel, Richard P

    2015-01-01

    The past decade has brought major improvements in large-scale asteroid discovery and characterization with over half a million known asteroids and over 100,000 with some measurement of physical characterization. This explosion of data has allowed us to create a new global picture of the Main Asteroid Belt. Put in context with meteorite measurements and dynamical models, a new and more complete picture of Solar System evolution has emerged. The question has changed from "What was the original compositional gradient of the Asteroid Belt?" to "What was the original compositional gradient of small bodies across the entire Solar System?" No longer is the leading theory that two belts of planetesimals are primordial, but instead those belts were formed and sculpted through evolutionary processes after Solar System formation. This article reviews the advancements on the fronts of asteroid compositional characterization, meteorite measurements, and dynamical theories in the context of the heliocentric distribution of...

  6. Handbook Timing Belts Principles, Calculations, Applications

    CERN Document Server

    Perneder, Raimund

    2012-01-01

    Timing belts offer a broad range of innovative drivetrain solutions; they allow low-backlash operation in robot systems, they are widely used in automated processes and industrial handling involving highly dynamic start-up loads, they are low-maintenance solutions for continuous operation applications, and they can guarantee exact positioning at high operating speeds. Based on his years of professional experience, the author has developed concise guidelines for the dimensioning of timing belt drives and presents proven examples from the fields of power transmission, transport and linear transfer technology. He offers definitive support for dealing with and compensating for adverse operating conditions and belt damage, as well as advice on drive optimization and guidelines for the design of drivetrain details and supporting systems. All market-standard timing belts are listed as brand neutral. Readers will discover an extensive bibliography with information on the various manufacturers and their websites. This...

  7. Simulation of engine auxiliary drive V-belt slip motion. Part 1. Development of belt slip model; Engine hoki V belt slip kyodo no simulation. 1. Belt slip model no kaihatsu

    Energy Technology Data Exchange (ETDEWEB)

    Kurisu, T. [Mazda Motor Corp., Hiroshima (Japan)

    1997-10-01

    V-belts are widely used for driving auxiliary components of an engine. Inadequet design of such belt system sometimes results in troubles such as belt squeak, side rubber separation and/or bottom rubber crack. However, there has been no design tools which can predict belt slip quantitatively. The author developed a motion simulation program of Auxiliary Drive V-Belt System considering belt slip. The program showed good prediction accuracy for belt slip motion. This paper describes the simulation model. 1 ref., 12 figs.

  8. Two Discrete UHP and HP Metamorphic Belts in the Central Orogenic Belt, China

    Institute of Scientific and Technical Information of China (English)

    Suo Shutian; Zhong Zengqiu; Zhang Li; Zhou Hanwen; You Zhendong

    2006-01-01

    An attempt is made to confirm the existence of the two discrete UHP and HP metamorphic belts in the central orogenic belt in China. Detailed geological mapping and structural and petrological analyses of the Kanfenggou (看丰沟) and Xiangfanggou ( 香坊沟 ) slices exposed in the eastern Qinling (秦岭) orogen indicate that they experienced ultrahigh pressure and high pressure metamorphism, respectively. The former, situated in northern Qinling, contains a large volume of fine-grained coesite and quartz pseudomorphs after coesite- and microdiamond-bearing eclogite lenses, whereas the latter, located in southern Qinling, preserves the relicts of a high pressure metamorphic mineral assemblage. Based on extensive fieldwork together with compilations at the scale of the orogenic belt, and a comparison of Pb isotopic compositions between the UHP metamorphic rocks from Kanfenggou slice and the Dabie UHP metamorphic belt, we propose that there are at least two discrete ultrahigh pressure metamorphic belts with different ages and tectonic evolution within the central orogenic belt in China. The first is the South Altun-North Qaidam-North Qinling ultrahigh pressure metamorphic belt of Early Paleozoic age (~ 500-400 Ma). The Kanfenggou ultrahigh pressure slab is located at its eastern segment. The second is the well constrained Dabie ( 大别 )-Sulu ( 苏鲁 ) ultrahigh/ high pressure metamorphic belt of Triassic age (~250-220 Ma). The Xiangfanggou high pressure metamorphic slab is a westward extension of the Dabie-Sulu ultrahigh/high pressure metamorphic belt. The Pb isotopic compositions of the UHP metamorphic rocks from Kanfenggou UHP fragment in East Qinling are different from those of the UHP rocks in Dabie UHP metamorphic belt, but are consistent with those of the rocks from the Qinling rock group and Erlangping (二郎坪) rock group. The East Qinling UHP metamorphic belt does not appear to link with the Dabie-Sulu UHP metamorphic belt. These two ultrahigh

  9. 螺旋输送装置的研究现状及未来发展%Present Situation and Future Development of Screw Conveyor

    Institute of Scientific and Technical Information of China (English)

    乌兰图雅; 王春光

    2014-01-01

    Screw conveyor becoming increasingly prevalent in a variety of industries , therefore it ’ s required higher per-formance .Study in screw conveyor is significant for implementing mechanization and automation of conveyors .This paper introduces the present situations of screw conveyors at home and abroad , elabrates the main problems in the development of the screw conveyors in our countries , and points out the development tendency , provides theory basis for the develop-ment of screw conveyors .%随着螺旋输送装置在多种行业中的应用日益扩大,对其性能要求也越来越高,因而对输送装置进行深入研究,对我国输送机械化和自动化具有现实意义。为此,对国内外螺旋输送装置的理论分析、设计制造及仿真研究进行综述,分析了目前螺旋输送装置存在的主要问题,探讨了今后研究方向。

  10. A new conveyor system based on a passive magnetic levitation unit having repulsive-type magnetic bearings

    Science.gov (United States)

    Ohji, T.; Ichiyama, S.; Amei, K.; Sakui, M.; Yamada, S.

    2004-05-01

    A magnetic repulsive-type conveyor system is proposed as a new application of repulsive-type magnetic bearings, which use repulsive forces between the stator and rotor permanent magnets. The proposed conveyer is composed by aligning many passive magnetic levitation units. Each unit also contains electromagnets to oscillate a levitator shaft in the radial direction. The way of generating vibration and rotation in the conveyance direction was examined by the various excitation methods.

  11. Determination of Effective Factors on Power Requirement and Conveying Capacity of a Screw Conveyor under Three Paddy Grain Varieties

    Directory of Open Access Journals (Sweden)

    Ezzatollah Askari Asli-Ardeh

    2012-01-01

    Full Text Available An experiment was conducted to investigate the effect of screw speed, inclination angle and variety on the required power, and conveying capacity of a screw conveyor. The experiment was designed with four levels of screw speed (600, 800, 1000, and 1200 rpm, five levels of inclination angle (0, 20, 40, 60, and 80∘, and three levels of variety (Alikazemi, Hashemi, and Khazar. The Length, diameter, and pitch of screw were 2, 0.78, and 0.5 m, respectively. The experimental design was a randomized complete block (RCB with factorial layout. Maximum and minimum power requirements of tested screw conveyor were 99.29 and 81.16 Watt corresponding to conveying capacity of 3.210 and 1.975 ton/hour obtained for khazar and Alikazemi varieties, respectively. The results indicated that as screw inclination angle increased from 0 to 80∘, the conveying capacity decreased significantly from 3.581 to 0.932 t/h. It can be concluded that the most conveying capacity was 4.955 t/h at tests with khazar variety and conveyor inclination angle zero degree.

  12. Determination of effective factors on power requirement and conveying capacity of a screw conveyor under three paddy grain varieties.

    Science.gov (United States)

    Askari Asli-Ardeh, Ezzatollah; Mohsenimanesh, Ahmad

    2012-01-01

    An experiment was conducted to investigate the effect of screw speed, inclination angle and variety on the required power, and conveying capacity of a screw conveyor. The experiment was designed with four levels of screw speed (600, 800, 1000, and 1200 rpm), five levels of inclination angle (0, 20, 40, 60, and 80°), and three levels of variety (Alikazemi, Hashemi, and Khazar). The Length, diameter, and pitch of screw were 2, 0.78, and 0.5 m, respectively. The experimental design was a randomized complete block (RCB) with factorial layout. Maximum and minimum power requirements of tested screw conveyor were 99.29 and 81.16 Watt corresponding to conveying capacity of 3.210 and 1.975 ton/hour obtained for khazar and Alikazemi varieties, respectively. The results indicated that as screw inclination angle increased from 0 to 80°, the conveying capacity decreased significantly from 3.581 to 0.932 t/h. It can be concluded that the most conveying capacity was 4.955 t/h at tests with khazar variety and conveyor inclination angle zero degree.

  13. Seat belts, airbags and child protection devices. [previously: Seat belts and child restraint seats.

    NARCIS (Netherlands)

    2010-01-01

    In the Netherlands, the use of seat belts results in a yearly reduction of hundreds of fatalities. Seat belts reduce the risk of fatal injury by 37 to 48%, depending on the position in the car. At 50%, the effect of child protection devices is even slightly higher. When last measured (in 2010), 97%

  14. Analysis of stress distribution of timing belts by FEM; Yugen yosoho ni yoru timing belt oryoku kaiseki (belt code oryoku bunpu kaiseki hokoku)

    Energy Technology Data Exchange (ETDEWEB)

    Furukawa, Y.; Tomono, K.; Takahashi, H.; Uchida, T. [Honda R and D Co. Ltd., Tokyo (Japan)

    1997-10-01

    A model of the belt analyzed by-ABAQUS (: a general nonlinear finite element program) successfully confirmed the mechanism that generates the belt cord stress. A quite good agreement between experimental and computed results for the stress distribution of the belt cord. It is found that maximum stress of the cords occurs near the root of the tooth by calculation, where the belt cords break off. 3 refs., 9 figs.

  15. Results from the preliminary conveyor evaluation of the high-energy beta scintillation sensor at the Fernald Soil Decontamination Pilot Plant

    International Nuclear Information System (INIS)

    W tested a high-energy beta scintillation sensor to evaluate its efficacy in continually characterizing washed soils moving on a conveyor belt at Fernald's Soil Decontamination Pilot Plant (SDPP). This sensor was originally developed for monitoring uranium-contaminated soils in the field. It has a multi-layer design that enables it to discriminate against lower-energy beta particles from natural sources. It can also distinguish, to some extent, gamma rays and cosmic-induced species. The sensor detects uranium activity indirectly, based on the assumption that secular equilibrium exists between the targeted radionuclide (234mPa) and its parent (238U). Several 1-h background counts were made at the SDPP each day of the evaluation period. The average background count rate was found to be comparable to that observed under previous laboratory conditions. Static runs were performed on soils from SDPP test runs No. 1 and No. 17 to determine the extent of any residual activity following the decontamination process. Soils were found to contain 158±30 pCi/g and 114±25 pCi/g of 234Th-234mPa (238U?), respectively. But the soils had considerable moisture, and concern existed that this moisture would act as an additional beta attenuator and thereby give results that were erroneously low. Therefore, a soil sample was baked overnight, and the hard-baked clay that resulted was ground into small fragments and counted. This sample was counted for 30 min as before, and the total activity was determined to be 313±44 pCi/g of 234Th 234mPa (238U?). Based on the test No. 1 results, a dry-to-wet activity ratio of 1.98 has been established. Hence, if the moisture content of test No. 17 was equivalent to that of test No. 1, the actual 234Th-234mPa (238U?) activity level is expected to be approximately 226 pCi/g

  16. Flat belt continuously variable high speed drive

    Energy Technology Data Exchange (ETDEWEB)

    Kumm, E.L.

    1992-02-01

    A study was undertaken at Kumm Industries funded by DOE in the NBS/DOE Energy-Related Inventions Program starting in August 1990 to design, construct and test a novel very high speed flat belt drive. The test arrangement as shown in Figure 1 consists of a multiple belt-pulley configuration that transmits power from a low speed (2000--4000 RPM) input to a small pulley turbine'' (27,000 to 55,000 RPM) and then to the low speed output variable radius pulley (2000--5000 RPM) via a special self-active tensioner. Transmitting 25 HP to and from the turbine'' corresponds to obtaining 50 HP in one direction only in a possible turbo compounded engine application. The high speed of the turbine'' belts, i.e. 100 meters/sec. at 55,000 RPM, while transferring substantial power is a new much higher operating regime for belts. The study showed that the available belts gave overall test rig efficiencies somewhat above 80% for the higher speeds (50,000 RPM) and higher powers (corresponding to above 90% in the turbocompound application) and a significantly better efficiencies at slightly lower speeds. The tests revealed a number of improved approaches in the design of such high speed drives. It appears that there is considerable possibility for further improvement and application of such equipment.

  17. Hydraulic engines in armoured conveyors; Motores hidraulicos en los transportadores blindados

    Energy Technology Data Exchange (ETDEWEB)

    Fernandez Fernandez, N.; Fernandez Equibar, J.L. [Hullera Vasco-Leones, S.A., Leon (Spain)

    1994-05-01

    The Sociedad Anonima Hullera Vasco-Leonesa (HVL) coal mining company in Spain is exploiting a deposit of large subvertical seams which are characterised by being highly tectonised. A very important part of the work of exploitation is developed in the depths of the mine with the aid of secondary ventilation. In the near future, which will characterise itself with the opening of the `New Mine`, this type of work will come to have a significant relevance in underground mining technology. The limitations of space and the presence of methane necessitate, as for many years, the use of pneumatic moving shields, with the great inconveniences which derive from them: reduced energy efficiency, and elevated production of dust and noise. For this HVL seek to introduce in a conventional working, at the bottom of the mine, a system of armoured conveyors driven by hydraulic units, which besides reducing and/or eliminating the problems referred to above serve, as in the past, to extend hydraulic energy into other parts of mining activity. In order to initiate the proposed investigation a pilot project will be partially financed by Ocicarbon. 5 figs.

  18. LOAD EQUILIBRATION OF WORKING PLACES ARRANGED ON CONVEYORS USED FOR FOOTWEAR UPPERS MANUFACTURING

    Directory of Open Access Journals (Sweden)

    HARNAGEA Florentina

    2016-05-01

    Full Text Available In the present paper there is presented how to achieve a load equilibration of workstations for a conveyor with imposed pace, in the case of manufacturing uppers for a women boots model. Equilibration of work charging is done by switching worker’s operations in order to use at full time each worker placed in the technological flow process. In the manufacruring process of shoe uppers of the considered model, there have been established the operative time and production rates per operation. Thus there has been calculated the work necessary amount Nci for accomplishing different production rates: Q=600,650, 700, 750... 900pairs/ 8 h and the necessary amount of work Nai was adopted. A technology line of manufacturing a footwear item is used at its optimum capacity when the number of work vacancy is minimum, 0.013 corresponding to a flow production of 700pairs / 8h the highest labor productivity being obtained, ie 17.5 pairs / worker • 8h. By equilibrating the work charge for each operation, it is obtained, for a daily production of 700pairs / 8h, a reduction of the number of workspaces from 40 to 36 workers and hence a labor productivity of 19.44 pairs / worker • 8h.

  19. Development of synchronous accessory belt type tear resistant control system for conveyor belt%同步辅带型输送带防撕裂控制系统的研制

    Institute of Scientific and Technical Information of China (English)

    徐伟

    2006-01-01

    介绍同步辅带型输送带防撕裂控制系统的组成、控制原理及安装运行.该系统主要包括电气自动控制系统和环行辅助带两部分.辅助带安装在输送带的内表面,与输送带同步运行.当输送带发生撕裂时,辅助带也被撕裂,此时传感器不能正确接收到预埋在辅助带内传感器线圈的信号,系统停车并报警,实现防撕裂保护功能.该系统还具有防止输送带打滑和跑偏等功能.

  20. The Compositions of Kuiper Belt Objects

    CERN Document Server

    Brown, Michael E

    2011-01-01

    Objects in the Kuiper belt are small and far away thus difficult to study in detail even with the best telescopes available at earth. For much of the early history of the Kuiper belt, studies of the compositions of these objects were relegated to collections of moderate quality spectral and photometric data that remained difficult to interpret. Much early effort was put into simple correlations of surface colors and identifications of spectral features, but it was difficult to connect the observations to a larger understanding of the region. The last decade, however, has seen a blossoming in our understanding of the compositions of objects in the Kuiper belt. This blossoming is a product of the discoveries of larger -- and thus easier to study -- objects, continued dedication to the collection of a now quite large collection of high quality photometric and spectroscopic observations, and continued work at the laboratory and theoretical level. Today we now know of many processes which affect the surface compos...

  1. Perceptual findings on the broadway belt voice.

    Science.gov (United States)

    DeLeo LeBorgne, Wendy; Lee, Linda; Stemple, Joseph C; Bush, Heather

    2010-11-01

    The present study required raters (casting directors) to evaluate the belt voice quality of 20 musical theater majors who were proficient in the singing style referred to as belting. Two specified vocalizes and six short excerpts from the belting repertoire were used for rating purposes. The raters were asked to judge the belters on a set of seven perceptual parameters (loudness, vibrato, ring, timbre, focus, nasality, and registration breaks), and then report an overall score for these student belters. The four highest and lowest average scores were used to establish the elite and average student belters. A correlation analysis and linear regression analysis provided insight regarding which perceptual judgments correlated most highly with the elite and average scores. The present study found the perceptual ratings of vibrato and ring to be most highly correlated to the elite student belter. In addition, vibrato and ring were found to highly correlate with perceived loudness. PMID:19900789

  2. Composite Microdiscs with a Magnetic Belt

    DEFF Research Database (Denmark)

    Knaapila, Matti; Høyer, Henrik; Helgesen, Geir

    2015-01-01

    We describe an emulsion-based preparation of patchy composite particles (diameter of 100-500 mu m) consisting of a disclike epoxy core and a belt of porous polystyrene particles (diameter of 30 mu m) with magnetite within the pores. Compared to the magnetically uniform polystyrene particles......, the spontaneous aggregation of composite particles is suppressed when dispersed into liquid, which is attributed to the increased particle size, reduced magnetic susceptibility, and the shape of the magnetic domain distribution within the particles (spherical versus a belt). When the composite particles...

  3. The thrust belts of Western North America

    Energy Technology Data Exchange (ETDEWEB)

    Moulton, F.C.

    1993-08-01

    Most of the Basin and Range physiographic province of western North America is now believed to be part of the overthrust. The more obvious overthrust belt along the eastern edge of the Basin and Range Province is named the Sevier orogenic belt, where older rocks are observed thrust onto younger rocks. More detailed surface geological mapping, plus deep multiple-fold geophysical work and many oil and gas wildcat wells, have confirmed an east-vergent shortened and stacked sequence is present in many places in the Basin and Range. This western compressive deformed area in east central Nevada is now named the Elko orogenic belt by the U.S. Geological Survey. This older compressed Elko orogenic belt started forming approximately 250 m.y. ago when the North American plate started to move west as the Pangaea supercontinent started to fragment. The North American plate moved west under the sediments of the Miogeocline that were also moving west. Surface-formed highlands and oceanic island arcs on the west edge of the North American plate restricted the westward movement of the sediments in the Miogeocline, causing east-vergent ramp thrusts to form above the westward-moving North American plate. The flat, eastward-up-cutting thrust assemblages moved on the detachment surfaces.

  4. Imaging Jupiter Radiation Belts At Low Frequencies

    Science.gov (United States)

    Girard, J. N.; de Pater, I.; Zarka, P.; Santos-Costa, D.; Sault, R.; Hess, S.; Cecconi, B.; Fender, R.; Pewg, Lofar

    2014-04-01

    The ultra-relativistic electrons, trapped in the inner radiation belts of Jupiter, generates a strong synchrotron radio emission (historically known as the jovian decimeter radiation (DIM)) which is beamed, polarized (~20% linear, ~1% circular) and broadband. It has been extensively observed by radio telescopes/ probes and imaged by radio interferometers over a wide frequency spectrum (from >300 MHz up to 22 GHz). This extended emission presents two main emission peaks constantly located on both sides of the planet close to the magnetic plane. High latitude emissions were also regularly observed at particular frequencies, times and in particular observational configurations. This region of the magnetosphere is "frozen" due to the strong magnetic field (~4.2 G as the equator) and therefore is forced to rotate at the planetary period (T≈9h55m). Due to the tilt (~ 10o) between the spin axis of the planet and the magnetic axis (which can be seen as dipolar in first approximation), the belts and the associated radio emission wobble around the planet center. The analysis of the flux at different frequencies highlighted spatial, temporal and spectral variabilities which origins are now partly understood. The emission varies at different time scales (short-time variations of hours to long-term variation over decades) due to the combination of visibility effect (wobbling, beaming, position of the observer in the magnetic rotating reference frame) [1], [2] and intrinsic local variations (interaction between relativistic electrons and satellites/dust, delayed effect of the solar wind ram pressure, impacts events) [3], [4], [5]. A complete framework is necessary to fully understand the source, loss and transport processes of the electrons originating from outside the belt, migrating by inward diffusion and populating the inner region of the magnetosphere. Only a few and unresolved measurements were made below 300 MHz and the nonsystematic observation of this radio emission

  5. 砷料送料机的螺旋输送机的设计%Design of Screw Conveyor in Arsenic Materials Feeder

    Institute of Scientific and Technical Information of China (English)

    刘涛; 陈秋月; 朱磊; 刘铁

    2014-01-01

    To meet the accurate feeding requirement of arsenic material feeder ,a screw conveyor is designed .The structure design and calculation of the screw conveyor under this working condition is introduced ,the transmission system of the device is described in detail .This screw conveyor can garantee the arsenic material's accurate feeding and improves the efficiency of equipment .%为满足砷料送料机工作的要求,采用螺旋输送机构进行精确送料,对此工况下所要求的螺旋输送机结构进行设计与计算,对其驱动装置做了深入设计,保证了砷料的精确送料,提高了设备的生产效率。

  6. An Integrated MCDM Model for Conveyor Equipment Evaluation and Selection in an FMC Based on a Fuzzy AHP and Fuzzy ARAS in the Presence of Vagueness.

    Science.gov (United States)

    Nguyen, Huu-Tho; Dawal, Siti Zawiah Md; Nukman, Yusoff; Rifai, Achmad P; Aoyama, Hideki

    2016-01-01

    The conveyor system plays a vital role in improving the performance of flexible manufacturing cells (FMCs). The conveyor selection problem involves the evaluation of a set of potential alternatives based on qualitative and quantitative criteria. This paper presents an integrated multi-criteria decision making (MCDM) model of a fuzzy AHP (analytic hierarchy process) and fuzzy ARAS (additive ratio assessment) for conveyor evaluation and selection. In this model, linguistic terms represented as triangular fuzzy numbers are used to quantify experts' uncertain assessments of alternatives with respect to the criteria. The fuzzy set is then integrated into the AHP to determine the weights of the criteria. Finally, a fuzzy ARAS is used to calculate the weights of the alternatives. To demonstrate the effectiveness of the proposed model, a case study is performed of a practical example, and the results obtained demonstrate practical potential for the implementation of FMCs. PMID:27070543

  7. 罗宾斯TBM连续皮带机急停系统改造%The Reforming of Robbins Company TBM Continuous Belt Stop System

    Institute of Scientific and Technical Information of China (English)

    李文帅

    2014-01-01

    Lanyu railway west Qinling tunnel XQLS2 mark right line engineering used TBM which was the production of U.S.ROBBINS company roadway construction.The rock ballast was con-veyed long distances to waste disposal area by continuous belt conveyor.The electrical control part was ultra long span cable signal transmission control system developed by the company for the first time.Due to construction environment constraints,the fiber easily broken,for the actual construction environment conditions,the continuous belt stop system for the technological trans-formation,to improve the reliability of the latter part of the construction of the system.%兰渝铁路西秦岭隧道 XQLS2标右线工程的采用 ROBBINS 公司生产的 TBM掘进施工。石渣由连续皮带机长距离运至洞外弃渣场,其电气控制部分是该公司首次研发的超长距离光缆信号传输控制系统。因受施工环境限制,其光纤易断,针对实际施工环境条件,对连续皮带急停系统进行了技术改造,提高了后期施工中该系统的可靠性。

  8. Detecting Extrasolar Asteroid Belts Through Their Microlensing Signatures

    CERN Document Server

    Lake, Ethan; Dong, Subo

    2016-01-01

    We propose that extrasolar asteroid belts can be detected through their gravitational microlensing signatures. Asteroid belt + star lens systems create so-called "pseudo-caustics", regions in the source plane where the magnification exhibits a finite but discontinuous jump. These features allow such systems to generate distinctive microlensing light curves across a wide region of belt parameter space and possess remarkably large lensing cross-sections. Sample light curves for a range of asteroid belt parameters are presented. In the near future, space-based microlensing surveys (e.g., WFIRST) may be able to discover extrasolar asteroid belts with masses of the order of $0.1 M_{\\oplus}$.

  9. DELTA机器人传送带与视觉的综合标定方法%Method of Integrated Calibration on DELTA Robot Conveyor and Vision

    Institute of Scientific and Technical Information of China (English)

    杨强; 刘冠峰

    2015-01-01

    In this paper we propose an method of integrated calibration on DELTA robot conveyor and vision. We first use the end of DELTA robot arm to touch the same point on the conveyor when the conveyor moves some distance,which allows us to obtain the value of the point’s location in the robot coordinate system and the corresponding value of the encoder.,then we get the scale factor of the robot and conveyor,determine the transformation matrix between the robot coordinate system and the conveyor coordinate system, then we can know the pose of the conveyor coordinate system relative to the coordinate system of the robot,which is the conveyor calibration. By using the camera to posit in contact with the robot at the same point, we obtain the intrinsic matrix and the external parameters matrix of the camera, which can know the transformation matrix between the robot coordinate system and the camera coordinate system, which is the robot vision calibration. DELTA robot conveyor and vision calibration will make the foundation of achieving DELTA robot high-precision control.%提出一种关于DELTA机器人传送带与视觉的综合标定方法。通过DELTA机器人臂末端在传送带移动一段距离接触传送带始末同一点,得到该点在机器人坐标系的位置和编码器上对应的读数,得到传送带与机器人的比例因子,确定机器人坐标系与传送带坐标系的转化矩阵,从而得到传动带相对于机器人坐标系的位姿,即传送带的标定。通过相机定位与机器人接触同一点,从而确定相机的内参矩阵与外参矩阵,从而得到机器人与相机坐标系的转换关系,即机器人视觉的标定。DELTA机器人传送带与视觉的标定,为DELTA机器人高精度控制的实现打下基础。

  10. Seat Belt Use Among Adult Workers - 21 States, 2013.

    Science.gov (United States)

    Boal, Winifred L; Li, Jia; Rodriguez-Acosta, Rosa L

    2016-01-01

    Roadway incidents involving motorized vehicles accounted for 24% of fatal occupational injuries in the United States during 2013 and were the leading cause of fatal injuries among workers.* In 2013, workers' compensation costs for serious, nonfatal injuries among work-related roadway incidents involving motorized land vehicles were estimated at $2.96 billion.(†) Seat belt use is a proven method to reduce injuries to motor vehicle occupants (1). Use of lap/shoulder seat belts reduces the risk for fatal injuries to front seat occupants of cars by 45% and the risk to light truck occupants by 60%.(§) To characterize seat belt use among adult workers by occupational group, CDC analyzed data from the 2013 Behavioral Risk Factor Surveillance System (BRFSS) and found that not always using a seat belt was significantly associated with occupational group after controlling for factors known to influence seat belt use. Occupational groups with the highest prevalences of not always using a seat belt included construction and extraction; farming, fishing, and forestry; and installation, maintenance, and repair. To increase seat belt use among persons currently employed, states can enact and enforce primary seat belt laws, employers can set and enforce safety policies requiring seat belt use by all vehicle occupants, and seat belt safety advocates can target interventions to workers in occupational groups with lower reported seat belt use. PMID:27309488

  11. Social anxiety disorder: radio electric asymmetric conveyor brain stimulation versus sertraline

    Directory of Open Access Journals (Sweden)

    Fontani V

    2011-11-01

    Full Text Available Vania Fontani1, Piero Mannu1,2, Alessandro Castagna1, Salvatore Rinaldi11Department of Neuro Psycho Physio Pathology, Rinaldi Fontani Institute, Florence; 2Psychic Studies Center, Cagliari, ItalyPurpose: Social anxiety disorder (SAD is a disabling condition that affects almost 5% of the general population. Many types of drugs have shown their efficacy in the treatment of SAD. There are also some data regarding psychotherapies, but no data are available today about the efficacy of brain stimulation techniques. The aim of the study is to compare the efficacy of noninvasive brain stimulation neuro psycho physical optimization (NPPO protocol performed by radio electric asymmetric conveyor (REAC with that of sertraline in adults with SAD.Patients and methods: Twenty SAD patients on sertraline were compared with 23 SAD patients who refused any drug treatment and who chose to be treated with NPPO-REAC brain stimulation. This was a 6-month, open-label, naturalistic study. Patients on sertraline received flexible doses, whereas NPPO-REAC patients received two 18-session cycles of treatment. Clinical Global Improvement scale items "much improved" or "very much improved" and Liebowitz Social Anxiety Scale total score variation on fear and avoidance components were used to detect the results. The statistical analysis was performed with t-test. All measures <0.05 have been considered statistically significant.Results: Ten of 23 subjects on NPPO-REAC and six of the 20 taking sertraline were much improved or very much improved 1 month after the first NPPO-REAC cycle (t1. Sixteen of the subjects on NPPO-REAC and ten of the subjects taking sertraline were much improved or very much improved 1 month after the second NPPO-REAC cycle (t2. In respect of the Liebowitz Social Anxiety Scale, at t1 NPPO-REAC resulted in statistically more efficacy for sertraline on both fear and avoidance total scores. At t2, NPPO-REAC resulted in statistically more efficacy for

  12. 宝通带业中试生产基地大楼的设计构思%The Design Concept for Pilot Production Base Building of Baotong Belt Co

    Institute of Scientific and Technical Information of China (English)

    张晨曦

    2012-01-01

    结合宝通带业宝通-高校先进输送带中试生产基地设计创作,阐述在地块限制条件较多的情况下如何进行创作,并强调建筑创作必须根据用地实际将使用功能和外观造型有机结合。%This paper illustrates the design process of the basement on which the advanced conveyor belt is in the pilot production of a college in Baotong. In the design process of which is restricted a lot, it clarified how to do well in achieving both the function and the outer style as well as emphasizing that the design must be focused on the circumstances in the present.

  13. Alien Asteroid Belt Compared to our Own

    Science.gov (United States)

    2005-01-01

    [figure removed for brevity, see original site] Figure 1: Band of Light Comparison This artist's concept illustrates what the night sky might look like from a hypothetical alien planet in a star system with an asteroid belt 25 times as massive as the one in our own solar system (alien system above, ours below; see Figure 1). NASA's Spitzer Space Telescope found evidence for such a belt around the nearby star called HD 69830, when its infrared eyes spotted dust, presumably from asteroids banging together. The telescope did not find any evidence for a planet in the system, but astronomers speculate one or more may be present. The movie begins at dusk on the imaginary world, when HD 69830, like our Sun, has begun to set over the horizon. Time is sped up to show the onset of night and the appearance of a brilliant band of light. This light comes from dust in a massive asteroid belt, which scatters sunlight. In our solar system, anybody observing the skies on a moonless night far from city lights can see the sunlight that is scattered by dust in our asteroid belt. Called zodiacal light and sometimes the 'false dawn,' this light appears as a dim band stretching up from the horizon when the Sun is about to rise or set. The light is faint enough that the disk of our Milky Way galaxy remains the most prominent feature in the sky. (The Milky Way disk is shown perpendicular to the zodiacal light in both pictures.) In contrast, the zodiacal light in the HD 69830 system would be 1,000 times brighter than our own, outshining even the Milky Way.

  14. The atmospheric implications of radiation belt remediation

    Directory of Open Access Journals (Sweden)

    C. J. Rodger

    2006-08-01

    Full Text Available High altitude nuclear explosions (HANEs and geomagnetic storms can produce large scale injections of relativistic particles into the inner radiation belts. It is recognised that these large increases in >1 MeV trapped electron fluxes can shorten the operational lifetime of low Earth orbiting satellites, threatening a large, valuable population. Therefore, studies are being undertaken to bring about practical human control of the radiation belts, termed "Radiation Belt Remediation" (RBR. Here we consider the upper atmospheric consequences of an RBR system operating over either 1 or 10 days. The RBR-forced neutral chemistry changes, leading to NOx enhancements and Ox depletions, are significant during the timescale of the precipitation but are generally not long-lasting. The magnitudes, time-scales, and altitudes of these changes are no more significant than those observed during large solar proton events. In contrast, RBR-operation will lead to unusually intense HF blackouts for about the first half of the operation time, producing large scale disruptions to radio communication and navigation systems. While the neutral atmosphere changes are not particularly important, HF disruptions could be an important area for policy makers to consider, particularly for the remediation of natural injections.

  15. Araguaia fold belt, new geochronological data

    International Nuclear Information System (INIS)

    The northern part of the Araguaia Fold Belt (AFB) outcrops in a N-S direction for about 400 km in the state of Tocantins. Dome-like structures occur in this fold belt also in a N-S direction. Both deformation and metamorphism increase from the West to the East. The basement of the AFB consist of Colmeia complex and Cantao gneiss, which crop out mainly in the core of the dome-like structures. The supracrustals rocks of the fold belt belongs to the Baixo Araguaia supergroup which is divided into the lower Estrondo group and the upper Tocantins group. Preliminary Sm-Nd data from the Colmeia complex (Grota Rica dome) gave Archean model ages of 2.8 Ga (TNd sub(DM)) while Rb-Sr data in the same rocks give an age of 2530 ± 200 Ma. In the others dome-like structures, the Rb-Sr systematics gave ages for the Colmeia a complex of 2239 ± 47 Ma (Colmeia structure) and 1972 ± 46 Ma (Lontra structure). These younger ages are believed to represent partial to total isotopic resetting of the Rb-Sr system during the Transamazonian Event. The Rb-Sr studies of the Cantao gneiss gave an age of 1774 ± 31 Ma. (author)

  16. Seat belt use during pregnancy in Iran: attitudes and practices

    Institute of Scientific and Technical Information of China (English)

    Mojgan Karbakhsh; Zahra Ershadi; Ali Khaji; Fatemeh Rahimi-Sharbaf

    2010-01-01

    Objective: Seat belt use during pregnancy reduces injury to the mother and her fetus. During recent years, the use of seat belts has been mandated by law in Iran. The purpose of this study was to determine the attitudes and practices of pregnant women regarding seat belt use.Methods: In this cross-sectional study, we asked 335 pregnant women at a hospital-based prenatal care clinic on the use of safety belt before and during pregnancy. SPSS version 13.0 was used for data analysis.Results: The mean age of study subjects was 27.3 years±5.3 years with the median of 27 years. Compared with the seat belt use before pregnancy, no change was detected in 48.7% of the women; seat belt use had increased in 17.5 %of them and decreased in 33.8 %. Eighty-one percent of women knew the correct placing of both lap belt and shoulder belt. Only 4% of women had received education on proper restraint use during pregnancy.Conclusions: The prevalence of seat belt use during pregnancy is lower than reports which are mostly from developed nations. The fact that about one-third of women have decreased their seat belt usage during pregnancy highlights the importance of education of mothers on this topic.

  17. Technical transformation of screw conveyors for PVC drying system%PVC 干燥系统螺旋输送器的技术改造

    Institute of Scientific and Technical Information of China (English)

    陈六娟; 张军锋

    2013-01-01

    介绍了PVC旋流干燥工艺中螺旋输送器存在的问题以及改造措施。%Problems existed in the crew conveyors for the cyclone drying process of PVC were in-troduced as well as technical transform measures.

  18. Characteristic analysis on screw conveyor used for lignite molding%褐煤成型用螺旋输送机的特性分析

    Institute of Scientific and Technical Information of China (English)

    郝兵; 崔郎郎; 李聪杰; 白爱民; 蒋惠民; 刘正魁; 高洁

    2013-01-01

    根据褐煤成型机用螺旋输送机的工作特点,通过对螺旋轴结构进行分析及试验研究,确定一种合理的螺旋结构.通过试验数据得出螺旋输送机输送能力受煤粉的水分、温度和粒度的影响.物料水分增加,会增加螺旋输送机的功耗;物料水分下降,既能降低螺旋输送机功耗,又能提升成型机的成型压力.因此,合理设计螺旋输送机的结构,可为成型机运行参数的确定提供参考.%Based on the operating features of the screw conveyor used for lignite molding machine,after the structure of the screw shaft was analyzed and tested,a screw with reasonable structure was determined.Test data showed the influences of moisture,temperature and granularity of pulverized coal on the transportation capacity of the screw conveyor.The moisture raise led to increase in power consumption of the screw conveyor; the moisture reduction led to decrease in power consumption of the screw conveyor and increase in molding pressure of the molding machine.The screw conveyor with reasonable structure could offer foundation for determining the operating parameters of the molding machine.

  19. Health Monitoring for Coated Steel Belts in an Elevator System

    OpenAIRE

    Yimei Mao; Zuoying Huang; Guiyun Tian; Hui Zhao; Huaming Lei

    2012-01-01

    This paper presents a method of health monitoring for coated steel belts in an elevator system by measuring the electrical resistance of the ropes embedded in the belt. A model on resistance change caused by fretting wear and stress fatigue has been established. Temperature and reciprocating cycles are also taken into consideration when determining the potential strength degradation of the belts. It is proved by experiments that the method could effectively estimate the health degradation of ...

  20. Modal analysis of coupled vibration of belt drive systems

    Institute of Scientific and Technical Information of China (English)

    LI Xiao-jun; CHEN Li-qun

    2008-01-01

    The modal method is applied to analyze coupled vibration of belt drive systems. A belt drive system is a hybrid system consisting of continuous belts modeled as strings as well as discrete pulleys and a tensioner arm. The characteristic equation of the system is derived from the governing equation. Numerical results demenstrate the effects of the transport speed and the initial tension on natural frequencies.

  1. Health Monitoring for Coated Steel Belts in an Elevator System

    Directory of Open Access Journals (Sweden)

    Huaming Lei

    2012-01-01

    Full Text Available This paper presents a method of health monitoring for coated steel belts in an elevator system by measuring the electrical resistance of the ropes embedded in the belt. A model on resistance change caused by fretting wear and stress fatigue has been established. Temperature and reciprocating cycles are also taken into consideration when determining the potential strength degradation of the belts. It is proved by experiments that the method could effectively estimate the health degradation of the most dangerous section as well as other ones along the whole belts.

  2. CHAOTIC BELT PHENOMENA IN NONLINEAR ELASTIC BEAM

    Institute of Scientific and Technical Information of China (English)

    张年梅; 杨桂通

    2003-01-01

    The chaotic motions of axial compressed nonlinear elastic beam subjected totransverse load were studied. The damping force in the system is nonlinear. Consideringmaterial and geometric nonlinearity, nonlinear governing equation of the system wasderived. By use of nonlinear Galerkin method, differential dynamic system was set up.Melnikov method was used to analyze the characters of the system. The results showed thatchaos may occur in the system when the load parameters P0 and f satisfy some conditions.The zone of chaotic motion was belted. The route from subharmonic bifurcation to chaoswas analyzed. The critical conditions that chaos occurs were determined.

  3. Dust bands in the asteroid belt

    Science.gov (United States)

    Sykes, Mark V.; Greenberg, Richard; Dermott, Stanley F.; Nicholson, Philip D.; Burns, Joseph A.

    1989-01-01

    This paper describes the original IRAS observations leading to the discovery of the three dust bands in the asteroid belt and the analysis of data. Special attention is given to an analytical model of the dust band torus and to theories concerning the origin of the dust bands, with special attention given to the collisional equilibrium (asteroid family), the nonequilibrium (random collision), and the comet hypotheses of dust-band origin. It is noted that neither the equilibrium nor nonequilibrium models, as currently formulated, present a complete picture of the IRAS dust-band observations.

  4. Parametric resonances of convection belt system

    Institute of Scientific and Technical Information of China (English)

    Zhi-an YANG; Gao-feng LI

    2009-01-01

    Based on the Coriolis acceleration and the Lagrangian strain formula,a generalized equation for the transverse vibration system of convection belts is derived using Newton's second law.The method of multiple scales is directly applied to the governing equations,and an approximate solution of the primary parameter resonance of the system is obtained.The detuning parameter,cross-section area,elastic and viscoelastic parameters,and axial moving speed have a significant influences on the amplitudes of steady-state response and their existence boundaries.Some new dynamical phenomena are revealed.

  5. Voltage-Mode All-Pass Filters Using Universal Voltage Conveyor and MOSFET-Based Electronic Resistors

    Directory of Open Access Journals (Sweden)

    N. Herencsar

    2011-04-01

    Full Text Available The paper presents two novel realizations of voltage-mode first-order all-pass filters. Both circuits use single universal voltage conveyor (UVC, single capacitor, and two grounded resistors. Using the two NMOS transistors-based realizations of the electronic resistor with two symmetrical power supplies, presented all-pass filter circuits can be easily made electronically tunable. Proposed filter structures provide both inverting and non-inverting outputs at the same configuration simultaneously and they have high-input and low-output impedances that are desired for easy cascading in voltage-mode operations. The nonidealities of the proposed circuits are also analyzed and compared. The theoretical results of both circuits are verified by SPICE simulations using TSMC 0.35 μm CMOS process parameters. Based on the evaluation, the behavior of one of the circuits featuring better performance was also experimentally measured using the UVC-N1C 0520 integrated circuit.

  6. Stabilization of electrostatic accelerator charging belt current

    International Nuclear Information System (INIS)

    For the purpose of improving reliability and quality of electrostatic accelerator basic parameters the stabilizer of charging belt current is developed. The stabilizer consists of two units: high-voltage unit and control unit. The charging rectifier assures voltage up to 60 kV at total current load of 750 μA. For the EG- 2.5 and the EGP-10 M accelerators supply circuits of charging device with an earth screen and posAitive voltage supply the needles. t the EGP-10-1 accelerator negative charging voltage is supplied to the screens of the charging device. ''Plus'' of the rectifier is earthed. Charging and recharging are performed by means of brushes slipping over the internal belt side. At all accelerators the stability of charging current mean value is not worse 0.1%. The highest response of the system are obtained at the EG-2.5 accelerator for account of rectifier load by charging current and instrument resistor from 140 to 400 MOhm

  7. Fading of Jupiter's South Equatorial Belt

    Science.gov (United States)

    Sola, Michael A.; Orton, Glenn; Baines, Kevin; Yanamandra-Fisher, Padma

    2011-01-01

    One of Jupiter's most dominant features, the South Equatorial Belt, has historically gone through a "fading" cycle. The usual dark, brownish clouds turn white, and after a period of time, the region returns to its normal color. Understanding this phenomenon, the latest occurring in 2010, will increase our knowledge of planetary atmospheres. Using the near infrared camera, NSFCAM2, at NASA's Infrared Telescope Facility in Hawaii, images were taken of Jupiter accompanied by data describing the circumstances of each observation. These images are then processed and reduced through an IDL program. By scanning the central meridian of the planet, graphs were produced plotting the average values across the central meridian, which are used to find variations in the region of interest. Calculations using Albert4, a FORTRAN program that calculates the upwelling reflected sunlight from a designated cloud model, can be used to determine the effects of a model atmosphere due to various absorption, scattering, and emission processes. Spectra that were produced show ammonia bands in the South Equatorial Belt. So far, we can deduce from this information that an upwelling of ammonia particles caused a cloud layer to cover up the region. Further investigations using Albert4 and other models will help us to constrain better the chemical make up of the cloud and its location in the atmosphere.

  8. Young Stellar Objects in the Gould Belt

    CERN Document Server

    Dunham, Michael M; Evans, Neal J; Broekhoven-Fiene, Hannah; Cieza, Lucas; Di Francesco, James; Gutermuth, Robert A; Harvey, Paul M; Hatchell, Jennifer; Heiderman, Amanda; Huard, Tracy; Johnstone, Doug; Kirk, Jason M; Matthews, Brenda C; Miller, Jennifer F; Peterson, Dawn E; Young, Kaisa E

    2015-01-01

    We present the full catalog of Young Stellar Objects (YSOs) identified in the 18 molecular clouds surveyed by the Spitzer Space Telescope "cores to disks" (c2d) and "Gould Belt" (GB) Legacy surveys. Using standard techniques developed by the c2d project, we identify 3239 candidate YSOs in the 18 clouds, 2966 of which survive visual inspection and form our final catalog of YSOs in the Gould Belt. We compile extinction corrected SEDs for all 2966 YSOs and calculate and tabulate the infrared spectral index, bolometric luminosity, and bolometric temperature for each object. We find that 326 (11%), 210 (7%), 1248 (42%), and 1182 (40%) are classified as Class 0+I, Flat-spectrum, Class II, and Class III, respectively, and show that the Class III sample suffers from an overall contamination rate by background AGB stars between 25% and 90%. Adopting standard assumptions, we derive durations of 0.40-0.78 Myr for Class 0+I YSOs and 0.26-0.50 Myr for Flat-spectrum YSOs, where the ranges encompass uncertainties in the ado...

  9. Ambient Response Analysis of the Great Belt Bridge

    DEFF Research Database (Denmark)

    Brincker, Rune; Frandsen, J. B.; Andersen, P.

    2000-01-01

    In this paper an ambient response analysis of the Great Belt Bridge is presented. The Great Belt Bridge is one of the largest suspension bridges in the world, and the analysis was carried out in order to investigate the possibilities of estimating reliable damping values from the ambient response...

  10. Teaching Taekwondo in Physical Education: Incorporating the Color Belt System

    Science.gov (United States)

    Oh, Hyun-Ju; Hannon, James C.; Banks, Aaron

    2006-01-01

    Taekwondo is an excellent lifetime physical activity that provides both physical and mental benefits to its participants. The color belt system may be creatively used in physical education to encourage improvement in all learning domains. This article provides information on incorporating the color belt system into physical education, and provides…

  11. Safety belt usage in Finland and in other Nordic countries.

    NARCIS (Netherlands)

    Valtonen, J.

    1992-01-01

    Legislation has played a significant role in increasing safety belt usage in Finland and in the other Nordic countries. Publicity and enforcement have, however, been required to support the legislation. The development of safety belt regulations has been nearly similar in all these countries, both i

  12. Canadian seat belt wearing rates, promotion programs, and future directions.

    NARCIS (Netherlands)

    Grant, B.A.

    1992-01-01

    On the basis of a national driver seat belt survey conducted in Canada each year, the most important results are presented. A number of programmes for increasing seat belt use has been evaluated in Canada. Finally, a description is given of some of the current and planned activities within Canada wh

  13. Landscape distribution characteristics of northern foothill belts of Tianshan Mountains

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The foothill belts of Tianshan Mountains are about 280 km long and 60 km wide, and the study area extends from Kuitun city to Fukang city. They are transitional belts between mountains and plains, appearing in three rows of folds with different morphologies and their age becoming younger from south to north. Based on GIS and RS methods, and materials of the previous researchers, this paper deals with the genetics of the foothill belts and their landscape features resulting from folding by neotectonic movements, and also describes their length, width and slope by remote sensing image interpretation. The characteristics of the foothill belts are found to be very important for the surrounding environment by preventing groundwater from flowing into plains, changing groundwater, increasing flow of surface runoff, in addition to their roles in protecting the surrounding environment. The purpose of this paper is to provide an in-depth understanding of the foothill belts and influence on its surrounding environment.

  14. a Wave Model for a Pneumatic Tyre Belt

    Science.gov (United States)

    PINNINGTON, R. J.; BRISCOE, A. R.

    2002-06-01

    A one-dimensional wave equation of an infinite flattened tyre belt is generated. The belt vibration is controlled by bending, tension, shear and the sidewall stiffness. The dispersion relations for two waves in the belt are calculated and used to find both the input impedance and attenuation on a tyre belt of infinite extent. Tension and the sidewall controls the deformation and stiffness below 100Hz. Waves propagate around the belt above this frequency. The wave speeds due to bending and shear were predicted and measured. The model presented here should be valid for the prediction of tyre response above about 400 Hz when for a car tyre the modal behaviour is observed to cease. In this high-frequency region, the tyre at the input appears to be of infinite extent.

  15. Radiation-belt dynamics during solar minimum. Technical report

    Energy Technology Data Exchange (ETDEWEB)

    Gussenhoven, M.S.; Mullen, E.G.; Holeman, E.

    1989-12-01

    Two types of temporal variation in the radiation belts are studied using low altitude data taken onboard the DMSP F7 satellite: those associated with the solar cycle and those associated with large magnetic storm effects. Over a three-year period from 1984 to 1987 and encompassing solar minimum, the protons in the heart of the inner belt increased at a rate of approximately 6% per year. Over the same period, outer zone electron enhancements declined both in number and peak intensity. During the large magnetic storm of February 1986, following the period of peak ring current intensity, a second proton belt with energies up to 50 MeV was found at magnetic latitudes between 45 deg. and 55 deg. The belt lasted for more than 100 days. The slot region between the inner and outer electron belts collapsed by the merging of the two populations and did not reform for 40 days.

  16. Experimental Measurements of Belt Gears in Newly Developed Device

    Directory of Open Access Journals (Sweden)

    Jozef Mascenik

    2016-05-01

    Full Text Available The paper deals with the alternative of determination of state of the belt gear. To realize themeasurements a newly developed device was designed for measurement and diagnostics of the belt gears. The main task is to detect the V-belt slip expressed by the coefficient of elastic creep and of specific slip with a measuring device. The measurements regarding can be performed if input revolutions of the electric motor and torque of the belt gear are constant whereas the tensioning force of the belt gear changes. It is also possible to perform the measurement if the input revolutions of the electric motor and the tensioning forces are constant and the torque changes.

  17. A Study on the Vibration of the Charging Belt in an Electrostatic Accelerator

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The vibration of the charging belt in an electrostatic accelerator has intense influences on the accelerator operation. A calculating model was set up in this paper to study the belt vibration. The results show that the belt tension, belt velocity and belt current all contribute to the belt vibration. There is an optimal relationship among the three factors by which the belt would run most smoothly. There exists a minimum value of optimal tension for various belt velocities. The vibrating frequency of the is generally around several Hz.

  18. Equilibria and Free Vibration of a Two-Pulley Belt-Driven System with Belt Bending Stiffness

    Directory of Open Access Journals (Sweden)

    Jieyu Ding

    2014-01-01

    Full Text Available Nonlinear equilibrium curvatures and free vibration characteristics of a two-pulley belt-driven system with belt bending stiffness and a one-way clutch are investigated. With nonlinear dynamical tension, the transverse vibrations of the translating belt spans and the rotation motions of the pulleys and the accessory shaft are coupled. Therefore, nonlinear piecewise discrete-continuous governing equations are established. Considering the bending stiffness of the translating belt spans, the belt spans are modeled as axially moving beams. The pattern of equilibria is a nontrivial solution. Furthermore, the nontrivial equilibriums of the dynamical system are numerically determined by using two different approaches. The governing equations of the vibration near the equilibrium solutions are derived by introducing a coordinate transform. The natural frequencies of the dynamical systems are studied by using the Galerkin method with various truncations and the differential and integral quadrature methods. Moreover, the convergence of the Galerkin truncation is investigated. Numerical results reveal that the study needs 16 terms after truncation in order to determine the free vibration characteristics of the pulley-belt system with the belt bending stiffness. Furthermore, the first five natural frequencies are very sensitive to the bending stiffness of the translating belt.

  19. East Central Uplift Belt of Junggar Basin

    Institute of Scientific and Technical Information of China (English)

    1996-01-01

    @@ Mosuowandong ( Z3 ) and Dongdaohaizi (Z4) are two bidding blocks located in the east part of central uplift Belt, the hinterland of Junggar Basin. Xinjiang Uygur Autonomous Region. It totally covers an area of 8 100km2. Topographically, the two blocks are quite gentle with elevation of 380-400 m on average. The north part is desert and the south area is good for farming. There are three ephemeral streams flowing across the desert from south to north. The ground water is buried at the depth ranging from 6 to 8 m. It belongs to continental climate with the annually averaged precipitation of 80 mm. The traffic is rather convenient in the south part of both blocks. There are several sand-paved roads and two asphalt roads connected with the highway from Karamay to Urumqi City.

  20. The Foundations of Radiation Belt Research

    Science.gov (United States)

    Ludwig, G. H.

    2008-12-01

    phenomenon. It also provided the first hint that there were two distinct radiation belts, although that conclusion was not reached until later. Although that new information was quickly announced, the results of the high altitude nuclear detonations were kept secret until well into 1959. They clearly revealed the charged particle shells created by the Argos nuclear detonations. The next major step in mapping and understanding the high-intensity radiation involved the launch of deep space probes Pioneers III and IV in December 1958 and March 1959. Although both launches fell short in their primary objective, to reach the moon, they traveled far enough from the Earth to fully meet the needs of the scientific experiment. They very clearly showed the two-radiation belt structure, and mapped its extent. They also showed the probable effect of a magnetic storm on 25 February, thus indicating the direct influence of solar activity on the outer belt. By the end of 1959, the existence of the Van Allen Radiation Belts and their general structure were solidly established, early information about the composition of the radiation was appearing in print, and energetic work was under way to understand the physics of the processes involved.

  1. 大容量物料存储输送中螺旋输送机的控制%Control of Large Capacity Storage Conveying Screw Conveyor

    Institute of Scientific and Technical Information of China (English)

    宋向前; 许胜; 沈春龙; 赵振江

    2015-01-01

    针对螺旋输送机在大容量物料输送过程中对超载敏感、易堵塞等问题,设计了大型料罐存储物料、以空气压缩泵及电动料罐阀为辅助动作、由螺旋输送机大容量输送的触摸屏控制系统。%In the process of screw conveyor in the bulk material on overload sensitive, blockage problem, the design of large tank storage material, with air compressor pump and electric tank valve action, assisted by a screw conveyor bulk transport of touch screen control system.

  2. 物料压缩率对长距离绞龙输送的影响%Effect of product compression ratio in the long transfer screw conveyor

    Institute of Scientific and Technical Information of China (English)

    崔斌; 孔震; 徐飞翔; 赵雪峰; 韩俊巍

    2013-01-01

    In this article we present the concepts of product compression ratio, and analyse the effect of product compression ratio in the long transfer screw conveyor, also give the solution for the jam which cause by the compression ratio in the long transfer screw conveyor.%文章提出了物料压缩率的概念,针对物料压缩率的特性对长距离绞龙的影响作出了分析,并且对长距离绞龙由于物料压缩率问题引起的堵料提出了解决方案。

  3. 粮食输送设备密封的重要性及其分类%The important and classification of seal for food conveyors

    Institute of Scientific and Technical Information of China (English)

    赵显荣; 付忠华

    2014-01-01

    It is necessary to ensure good seal performance for food conveyors .this article introduces emphasize several common seal construction,for example,woolens seal、flexible filler seal、high molecule material seal and so on , and the development tendency of seal requirement in the food conveyors.%粮食输送设备具有良好的密封性能是很必要的,本文重点介绍了毛毡密封、软填料密封、高分子材料密封等几种常见的密封结构及粮食输送设备密封要求的发展趋势。

  4. 螺旋输送钢球过程中的粒子夹卡问题%Particle clamping problem during delivery of steel particles by screw conveyor

    Institute of Scientific and Technical Information of China (English)

    崔海博; 赵惠清

    2012-01-01

    在粒子冲击钻井系统中,钢球高压螺旋输送机是关键装置之一.因钢球材质的特性及输送工况与常规螺旋输送机有着很大差异,进而所造成的钢球夹卡现象(严重时导致闷车)是不容忽视的问题.文中通过试验研究,找出了钢球在螺旋输送过程中极易夹卡的位置,分析了各种夹卡现象存在的原因,对螺旋输送机的结构进行了适应性改进.%The screw conveyor delivering steel particles material under high pressure is among key facilities of particle ?injection system used for the particle impact drilling. The steel particles would always be got stuck is a serious problem. Because the nature of steel particles and the working conditions of screw conveyor is different from conventional screw conveyor. This article finds out where it happens, analyzes the reason and finishes the structural improvement by experiment. The paper has researched influence.

  5. 半封闭螺旋输送机运动量及几何参数确定%Semi-enclosed Screw Conveyor Exercise and Geometric Parameters

    Institute of Scientific and Technical Information of China (English)

    李新; 薛风

    2013-01-01

      Based on the closed spiral conveyor within a single material as the research object, this paper carries on the analysis, obtains the granular material parameter design criterion and the formula for calculation and checking, providing the way for selecting and determining semi-enclosed screw conveyor operating parameters and geometric parameters, to be conduce to semi hermetic screw conveyor design and application.%  通过对半封闭螺旋输送机内单颗物料为研究对象进行分析,得出了输送散体物料过程中主要参数设计准则及其计算和校验公式,为半封闭螺旋输送机的工作参数和几何参数的选择和确定提供了方法,有助于半封闭螺旋输送机的设计和应用。

  6. Geometry, kinematics and evolution of the Tongbai orogenic belt

    Institute of Scientific and Technical Information of China (English)

    HUANG Shaoying; XU Bei; WANG Changqiu; ZHAN Sheng; DENG Rongjing

    2006-01-01

    The Tongbai orogenic belt (TOB) is composed of six tectonic units. From south to north these units are: Tongbai gneiss rise (TGR); Hongyihe-Luozhuang eclogite belt (HLE); Maopo-Hujiazhai igneous rock belt (MHI); Zhoujiawan flysch belt (ZFB); Yangzhuang greenschist belt (YGB); and Dongjiazhuang marble belt (DMB).The geometry and kinematic images of the TOB include: the antiformal structures caused by a later uplift process, the top-to-north ductile shear structure that related to a process that the ultrahigh pressure rocks are brought to surface, the top-to-south ductile shear thrust and the sinistrial shear structures related to a south-north direction compression, and the east-west direction fold structures in the upper crust. In the view of the multistage subduction-collision orogenic belt, according to the characters of petrology and its distribution, geometry, kinematics and structural chronology in these tectonic units, tectonic evolution of the TOB can be divided into four stages: oceanic crust subduction during 400-300 Ma, continental collision during 270-250 Ma, continental deep subduction and uplift during 250-205 Ma and doming deformation during 200-185 Ma.

  7. Power Transmission Through Timing Belt In Two Wheeler Motors

    Directory of Open Access Journals (Sweden)

    Gurumurthy Veerapathiran

    2015-03-01

    Full Text Available This paper studies the effect of noise and friction on performance of the chain drive system for motor bikes. Experiment shows that chain transmission in chain drive system leads to poor overall performance, due to its noise and chain gets loose due to aging and sprockets wear due to chain friction etc., the proposed system consists of drive and driven pulley with timing belt transmission. Compared to conventional method, proposed method give improved tension in pulleys and belt by the additional arrangement called belt tensioner. This gives good overall performance of the system, and reduces noise, vibration and gives high transmission speed.

  8. Detection of Small Kuiper Belt Objects by Stellar Occultations

    OpenAIRE

    Stevenson, R

    2007-01-01

    Knowledge of the Kuiper Belt is currently limited to those objects that can be detected directly. Objects with diameters less than $\\sim$10km reflect too little light to be detected. These smaller bodies could contain most of the mass in the Kuiper Belt while the abundance of these bodies may constrain the distribution of mass. The overall size distribution of bodies within the Kuiper Belt can also be inferred from the relative abundances of sub-km and larger bodies. Stellar occultations are ...

  9. MACRO MODEL OF SEAT BELT USE BY CAR DRIVERS AND PASSENGERS

    Directory of Open Access Journals (Sweden)

    Kazimierz JAMROZ

    2013-12-01

    Full Text Available The article presents some problems of seat belt use by car drivers and passengers. It looks in particular at seat belt use and effectiveness in selected countries. Next, factors of seat belt use are presented and methodology of model development. A macro model of seat belt use is presented based on data from around fifty countries from different continents.

  10. Noninvasive radioelectric asymmetric conveyor brain stimulation treatment improves balance in individuals over 65 suffering from neurological diseases: pilot study

    Directory of Open Access Journals (Sweden)

    Margotti ML

    2012-02-01

    Full Text Available Vania Fontani1, Salvatore Rinaldi1, Alessandro Castagna1, Matteo Lotti Margotti21Department of Neuro Psycho Physio Pathology, Rinaldi Fontani Institute, Florence, Italy; 2Department of Information Technology and Statistical Analysis, Rinaldi Fontani Institute, Florence, ItalyPurpose: In the elderly population, problems with walking and balance are very common. These problems seriously affect the quality of life of the elderly. When gait and balance problems are caused by neurological disease, these problems can be more serious and difficult to handle. The aim of this pilot study was to verify the effect of a noninvasive radioelectric conveyor asymmetric brain stimulation protocol, named neuropostural optimization (NPO, to improve balance in neurological elderly.Patients and methods: Twelve patients suffering from various neurological diseases participated in this study. They were assessed with the Romberg test, which was performed on a computerized stabilometric platform before, immediately following, and 72 hours after NPO was used to improve balance.Results: The results showed that a stabilization of balance was recorded in all subjects a few minutes after administration of NPO. This stabilization increased 72 hours after treatment.Conclusion: The results show that NPO could be a valuable therapeutic approach to improve sensory-motor strategies and neurological control of balance in elderly patients suffering from various neurological diseases.Keywords: Romberg test, instability, imbalance, gait, REAC, neuropostural optimization

  11. 螺旋输送机螺旋体优化设计%Optimization Design of Screw in Screw Conveyor

    Institute of Scientific and Technical Information of China (English)

    王铁流; 郭晓梅; 陈仙明

    2012-01-01

    The process of finite element analysis and optimization design of screw for screw conveyor with the Pro/Engineer is discussed, the main steps and methods are also introduced. Subject to the requirements of the structural parameters and design objectives, the optimal design is realized efficiently and rapidly. A practical method is improved for the design quality of screw.%应用Pro/Engineer软件,研究了螺旋输送机螺旋体的有限元分析和优化设计方法和过程,介绍了设计过程的主要步骤和方法.在满足结构参数和设计目标要求的前提下,快捷、有效地实现了优化设计,提高了设计质量,为螺旋体的设计提供了一种有效的方法.

  12. 一种电动辊道输送车%One Type of Electric Roller Conveyor Truck

    Institute of Scientific and Technical Information of China (English)

    祝洲杰; 吴锂力

    2015-01-01

    Based on the accurate judgment of warehousing market and combined with the actual needs of customers,designed a new type of electric roller conveyor truck. This paper introduces the technical characteristics and performance characteristics of this truck , elaborates the structure. This truck provides a good solution to solve the actual problems in some working conditions.%通过对仓储物流细分市场的准确判断,结合客户的实际需求,研制了全电动辊道输送车。本文介绍了该车型的主要技术特点和性能特点,详细阐述了其结构实现方式和工作原理。该车型为解决某些工况环境下的实际问题提供了良好的解决方案。

  13. Experiment on asphalt mixture segregation in screw conveyor%沥青混合料在螺旋处的离析试验

    Institute of Scientific and Technical Information of China (English)

    谢立扬; 张晨光; 赵利军

    2013-01-01

    In order to exactly find out segregation reasons and segregation distribution regularities of asphalt mixture in screw conveyor during the paving process,based on the kinetic characteristics of mixture,this paper analyzed the relationship between the particles' axial and circumferential velocity and radius,pitch,rotational speed and friction coefficient under the action of screw conveyor.Meanwhile,field tests were conducted to get the segregation distribution regularities of asphalt mixture in screw conveyor.The results indicate that the mixture segregation is mainly affected by the spiral structure and the kinetic parameters.With the increase of radius,the particles' axial velocity monotonically increases,the circumferential velocity increases first and then decreases and the circumferential velocity is approximately equal to the axial velocity in the primary working range (radius 14~21 cm).So the segregation can be restricted by changing the rotational speed of screw conveyor and the relative position of screw conveyor and asphalt mixture.The asphalt content in the upper part of the screw is 2% higher than that in the bottom,the asphalt content in the central part of the screw is 0.7 % higher than that in both sides,the deviation of asphalt mixture gradation is in the specified range,but the asphalt mixture in the upper part of the screw contains more fine aggregate.Using the method of completely burying the crew conveyor,we can solve the asphalt content segregation occurring in the crew suspension.But the segregation between the upper and the lower part of the crew conveyor still exists.2 tabs,9 figs,11 refs.%为准确掌握摊铺过程中沥青混合料在螺旋分科器中的离析原因及分布规律,基于混合料在螺旋内的运动特性,分析了螺旋作用下混合料颗粒的轴向速度及圆周速度与螺旋半径、节距、转速及摩擦因数之间的关系,并通过现场试验给出了混合料离析在螺旋中的分布规律.结果

  14. 4 National Standards for Rubber Belt Products Issued

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    On May 20, National General Administration of Quality Supervision, Inspection and Quarantine and National Standardization Administration approved to issue 4 national standards for rubber belt products, which come into effect from October 1.

  15. Face-Saving Devices: Seat Belts and Air Bags

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_160032.html Face-Saving Devices: Seat Belts and Air Bags Using ... 11 percent) suffered facial fractures -- nasal and mid-face fractures most often. Those most likely to suffer ...

  16. Periumbilical allergic contact dermatitis: blue jeans or belt buckles?

    Science.gov (United States)

    Byer, Tara T; Morrell, Dean S

    2004-01-01

    Nickel is the most ubiquitous contact allergen among children and adolescents. Metal blue jeans buttons and belts have been noted to cause nickel dermatitis around the umbilicus. For these children, traditional teaching is strict avoidance of all pants with metal snaps/buttons, particularly blue jeans. In this study we tested 90 pairs of blue jeans and 47 belts for nickel using the dimethylglyoxime spot test. Only 10% of blue jeans tested positive, while 53% of belts tested positive. Furthermore, 10 pairs of nickel-negative blue jeans remained negative after 10 washings. Overall we found no resistance to testing in clothing stores. From these results, we recommend that patients with allergic contact dermatitis secondary to nickel need not strictly avoid blue jeans and metal belt buckles. Rather, families should be encouraged to use the dimethylglyoxime spot test to test these items for nickel prior to purchase.

  17. "Abomination"--life as a Bible belt gay.

    Science.gov (United States)

    Barton, Bernadette

    2010-01-01

    Drawing on observation, autoethnography, and audio-taped interviews, this article explores the religious backgrounds and experiences of Bible Belt gays. In the Bible Belt, Christianity is not confined to Sunday worship. Christian crosses, messages, paraphernalia, music, news, and attitudes permeate everyday settings. Consequently, Christian fundamentalist dogma about homosexuality-that homosexuals are bad, diseased, perverse, sinful, other, and inferior-is cumulatively bolstered within a variety of other social institutions and environments in the Bible Belt. Of the 46 lesbians and gay men interviewed for this study (age 18-74 years), most describe living through spirit-crushing experiences of isolation, abuse, and self-loathing. This article argues that the geographic region of the Bible Belt intersects with religious-based homophobia. Informants explained that negative social attitudes about homosexuality caused a range of harmful consequences in their lives including the fear of going to hell, depression, low self-esteem, and feelings of worthlessness.

  18. "Abomination"--life as a Bible belt gay.

    Science.gov (United States)

    Barton, Bernadette

    2010-01-01

    Drawing on observation, autoethnography, and audio-taped interviews, this article explores the religious backgrounds and experiences of Bible Belt gays. In the Bible Belt, Christianity is not confined to Sunday worship. Christian crosses, messages, paraphernalia, music, news, and attitudes permeate everyday settings. Consequently, Christian fundamentalist dogma about homosexuality-that homosexuals are bad, diseased, perverse, sinful, other, and inferior-is cumulatively bolstered within a variety of other social institutions and environments in the Bible Belt. Of the 46 lesbians and gay men interviewed for this study (age 18-74 years), most describe living through spirit-crushing experiences of isolation, abuse, and self-loathing. This article argues that the geographic region of the Bible Belt intersects with religious-based homophobia. Informants explained that negative social attitudes about homosexuality caused a range of harmful consequences in their lives including the fear of going to hell, depression, low self-esteem, and feelings of worthlessness. PMID:20391006

  19. 5m Main Belt Asteroid Population Estimation Using Vesta Imagery

    Science.gov (United States)

    Rynders, Michael; Trilling, David E.

    2016-10-01

    The Main Belt is the largest source of Near-Earth asteroids, but objects 2 pixels in diameter that were counted in a 33km 2 region to give a crater density. By knowing the crater density and making some reasonable assumptions about the orbital distribution of asteroids and the age of Vesta's surface, an estimate of the population of small asteroids in the inner main belt was made. It was found that the inner region of the main asteroid belt contains approximately 20 billion asteroids larger than 5 m. These results agree well with the measured inner Main Belt Size distribution derived by the Wide-field Infrared Survey Explorer, WISE (Masiero et al. 2011).

  20. FORMATION AND EVOLUTION OF THE CENOZOIC THRUST FOLD BELT IN JINPING, SICHUAN

    Institute of Scientific and Technical Information of China (English)

    LIAO Zhongli; DENG Yongfu; LIAO Guangyu

    2003-01-01

    The Jinping orogenic belt in Sichuan, China consists mainly of the Jinpingshan intracontinental thrust-nappe belt, foreland thrust-nappe belt and foreland uplift belt. Based on analyses about the characteristics of the structural units in this area, the authors propose in this paper that Chapuzi-Bazhe revival fault belt is the regional boundary fault, and points out that after the formation of the Pre-Sinian basement, the western edge of the Yangtze paraplatform was turned into the passive continental margin in Sinian to Triassic, then into the Mesozoic collision orogenic belt, and finally into the Cenozoic orogenic belt through intracontinental orogeny.

  1. Cenozoic intracontinental deformation of the Kopeh Dagh Belt, Northeastern Iran

    Science.gov (United States)

    Chu, Yang; Wan, Bo; Chen, Ling; Talebian, Morteza

    2016-04-01

    Compressional intracontinental orogens represent large tectonic zones far from plate boundaries. Since intracontinental mountain belts cannot be framed in the conventional plate tectonics theory, several hypotheses have been proposed to account for the formations of these mountain belts. The far-field effect of collision/subduction at plate margins is now well accepted for the origin and evolution of the intracontinental crust thickening, as exemplified by the Miocene tectonics of central Asia. In northern Iran, the Binalud-Alborz mountain belt witnessed the Triassic tectonothermal events (Cimmerian orogeny), which are interpreted as the result of the Paleotethys Ocean closure between the Eurasia and Central Iran blocks. The Kopeh Dagh Belt, located to the north of the Binalud-Alborz Belt, has experienced two significant tectonic phases: (1) Jurassic to Eocene rifting with more than 7 km of sediments; and (2) Late Eocene-Early Oligocene to Quaternary continuous compression. Due to the high seismicity, deformation associated with earthquakes has received more and more attention; however, the deformation pattern and architecture of this range remain poorly understood. Detailed field observations on the Cenozoic deformation indicate that the Kopeh Dagh Belt can be divided into a western zone and an eastern zone, separated by a series of dextral strike-slip faults, i.e. the Bakharden-Quchan Fault System. The eastern zone characterized by km-scale box-fold structures, associated with southwest-dipping reverse faults and top-to-the NE kinematics. In contrast, the western zone shows top-to-the SW kinematics, and the deformation intensifies from NE to SW. In the northern part of this zone, large-scale asymmetrical anticlines exhibit SW-directed vergence with subordinate thrusts and folds, whereas symmetrical anticlines are observed in the southern part. In regard to its tectonic feature, the Kopeh Dagh Belt is a typical Cenozoic intracontinental belt without ophiolites or

  2. SPECIFIC RESISTANCE AND SPECIFIC INTENSITY OF BELT SANDING OF WOOD

    Directory of Open Access Journals (Sweden)

    Boleslaw Porankiewicz

    2010-06-01

    Full Text Available This paper examines and discusses the specific belt sanding resistance K (N·cm-2 and specific belt sanding intensity SI (g·cm-2·min-1, for wood of Pinus sylvestris L., Picea abies L., Quercus robra L., Acer pseudoplatanus L., Alnus glutinosa Gaertn., and Populus Nigra L., by different sanding pressure pS, different sanding grit NG number, and different wood grain angles Phi(v.

  3. Tribological Properties of Metal V-Belt Type CVT Lubricant

    OpenAIRE

    Keiichi Narita

    2012-01-01

    The priority for lubricant performance for metal V-belt-type CVT (B-CVTFs) should be the improvement of transmittable torque capacity between the belt and pulley plus excellent antishudder properties for lockup clutch used in B-CVTs. This study intends to investigate the effect of lubricant additives for improving these performances of B-CVTs. In addition, surface analysis techniques were utilized to gain a novel insight into the chemical composites and morphology of the tribofilms. As a resu...

  4. Promoting automobile safety belt use by young children.

    OpenAIRE

    Sowers-Hoag, K M; Thyer, B A; Bailey, J S

    1987-01-01

    A program using behavioral practice, assertiveness training, and social and contrived reinforcers was developed to establish and maintain automobile safety belt use by young children. Sixteen children (ages 4.8 to 7 years) who never used their safety belts during a 5-day preexperimental observation period were randomly assigned to two groups of eight each. A multiple baseline design across groups was used to evaluate the effectiveness of the training program. During the 8-day baseline period ...

  5. Design of MGA trajectories for main belt asteroid

    Institute of Scientific and Technical Information of China (English)

    崔祜涛; 乔栋; 崔平远; 栾恩杰

    2003-01-01

    Asteroid exploration is one of the most sophisticated missions currently being investigated. Gravityassist trajectories have proven valuable in interplanetary missions such as the Pioneer, Voyager and Galileo. In this paper, we design interplanetary trajectory for main belt asteroid exploration mission with the Mars gravityassist (MGA) using "pork chop" plots and patched-conic theory and give some initial valuable trajectory parameters on main belt asteroid exploration mission with MGA.

  6. Occultation Searches for Kuiper Belt Objects

    CERN Document Server

    Cooray, A R; Cooray, Asantha; Farmer, Alison J.

    2003-01-01

    The occultation of background stellar sources by foreground Kuiper Belt Objects (KBOs) can be used to survey physical properties of the KBO population. We discuss statistics related to a KBO occultation survey, such as the event duration distribution, and suggest that occultation searches can be effectively used to probe the KBO size distribution below 10 km. In particular, we suggest that occultation surveys may be best suited to search for a turnover radius in the KBO size distribution due to collisions between small-size objects. For occultation surveys that monitor stellar sources near the ecliptic over a few square degrees, with time sampling intervals of order 0.1 sec and sensitivity to flux variations of a few percent or more, a turnover radius between 0.1 and 1.0 km can be probed. While occultation surveys will probe the low-radius limit and imaging surveys will detect KBOs of size 100 km or more, statistics of objects with sizes in the intermediate range of around 1 km to 100 km will likely remain un...

  7. Orion revisited III. The Orion Belt population

    CERN Document Server

    Kubiak, K; Bouy, H; Sarro, L M; Ascenso, J; Burkert, A; Forbrich, J; Großschedl, J; Hacar, A; Hasenberger, B; Lombardi, M; Meingast, S; Köhler, R; Teixeira, P S

    2016-01-01

    This paper continues our study of the foreground population to the Orion molecular clouds. The goal is to characterize the foreground population north of NGC 1981 and to investigate the star formation history in the large Orion star-forming region. We focus on a region covering about 25 square degrees, centered on the $\\epsilon$ Orionis supergiant (HD 37128, B0\\,Ia) and covering the Orion Belt asterism. We used a combination of optical (SDSS) and near-infrared (2MASS) data, informed by X-ray (\\textit{XMM-Newton}) and mid-infrared (WISE) data, to construct a suite of color-color and color-magnitude diagrams for all available sources. We then applied a new statistical multiband technique to isolate a previously unknown stellar population in this region. We identify a rich and well-defined stellar population in the surveyed region that has about 2\\,000 objects that are mostly M stars. We infer the age for this new population to be at least 5\\, Myr and likely $\\sim10$\\,Myr and estimate a total of about 2\\,500 mem...

  8. Detecting Mass Loss in Main Belt Asteroids

    Science.gov (United States)

    Sandberg, Erik; Rajagopal, Jayadev; Ridgway, Susan E.; Kotulla, Ralf C.; Valdes, Francisco; Allen, Lori

    2016-01-01

    Sandberg, E., Rajagopal, J., Ridgway, S.E, Kotulla, R., Valdes, F., Allen, L.The Dark Energy Camera (DECam) on the 4m Blanco telescope at the Cerro Tololo Inter-American Observatory (CTIO) is being used for a survey of Near Earth Objects (NEOs). Here we attempt to identify mass loss in main belt asteroids (MBAs) from these data. A primary motivation is to understand the role that asteroids may play in supplying dust and gas for debris disks. This work focuses on finding methods to automatically pick out asteroids that have qualities indicating possible mass loss. Two methods were chosen: looking for flux above a certain threshold in the asteroid's radial profile, and comparing its PSF to that of a point source. After sifting through 490 asteroids, several have passed these tests and should be followed up with a more rigorous analysis.Sandberg was supported by the NOAO/KPNO Research Experience for Undergraduates (REU) Program which is funded by the National Science Foundation Research Experiences for Undergraduates Program (AST-1262829)

  9. Dark nebulae, dark lanes, and dust belts

    CERN Document Server

    Cooke, Antony

    2012-01-01

    As probably the only book of its type, this work is aimed at the observer who wants to spend time with something less conventional than the usual fare. Because we usually see objects in space by means of illumination of one kind or another, it has become routine to see them only in these terms. However, part of almost everything that we see is the defining dimension of dark shading, or even the complete obscuration of entire regions in space. Thus this book is focused on everything dark in space: those dark voids in the stellar fabric that mystified astronomers of old; the dark lanes reported in many star clusters; the magical dust belts or dusty regions that have given so many galaxies their identities; the great swirling 'folds' that we associate with bright nebulae; the small dark feature detectable even in some planetary nebulae; and more. Many observers pay scant attention to dark objects and details. Perhaps they are insufficiently aware of them or of the viewing potential they hold, but also it may be...

  10. Forming the Cold Classical Kuiper Belt in a light Disk

    CERN Document Server

    Shannon, Andrew; Lithwick, Yoram

    2015-01-01

    Large Kuiper Belt Objects are conventionally thought to have formed out of a massive planetesimal belt that is a few thousand times its current mass. Such a picture, however, is incompatible with multiple lines of evidence. Here, we present a new model for the conglomeration of Cold Classical Kuiper belt objects, out of a solid belt only a few times its current mass, or a few percent of the solid density in a Minimum Mass Solar Nebula. This is made possible by depositing most of the primordial mass in grains of size centimetre or smaller. These grains collide frequently and maintain a dynamically cold belt out of which large bodies grow efficiently: an order-unity fraction of the solid mass can be converted into large bodies, in contrast to the ~0.1% efficiency in conventional models. Such a light belt may represent the true outer edge of the Solar system, and it may have effectively halted the outward migration of Neptune. In addition to the high efficiency, our model can also produce a mass spectrum that pe...

  11. Delivery of meteorites from the asteroid belt

    Science.gov (United States)

    Nolan, Michael Craig

    The process of the delivery of meteorites to the surface of the Earth from plausible source regions such as the asteroid belt is currently understood in general terms, but important uncertainties and conflicts remain to be resolved. Stochastic effects of the rare disruptions of large asteroids on the population of meteorite-sized Earth-crossing asteroids can change the flux and the proportions of compositional types in the infalling meteorite population. These changes can be significant in magnitude over timescales of 108 years. Changes of the order of 1 percent can be expected on timescales of 105-106 y, consistent with small differences between the Antarctic meteorites and modern falls. The magnitude of changes depends strongly on poorly-understood details of collisions. Asteroids 961 Gaspra and 243 Ida were recently imaged by the Galileo spacecraft. I use a numerical hydrocode model to examine the outcomes of various sire impacts into targets the sizes of these asteroids. A shock wave fractures the asteroid in advance of crater excavation flow; thus, for impactors larger than 100 m, impacting at 5.3 km s-1, tensile strength is unimportant in these bodies, whether they are initially intact or are 'rubble piles'. Because of the shock-induced fracture, impact results are controlled by gravity. Therefore these asteroids are much more resistant to catastrophic disruption than predicted by previous estimates, which had assumed that strength was controlling these processes for rock targets. Fracture of km-size asteroids is different from fracture in terrestrial experiments using few-cm targets. The composition distribution of delivered meteorites depends on the outcomes of such asteroid impacts.

  12. Activating main belt comets by collisions

    Science.gov (United States)

    Maindl, T. I.; Haghighipour, N.; Schäfer, C.; Speith, R.

    2016-02-01

    Since their identification as a new class of bodies by Hsieh and Jewitt in 2006 active asteroids (or Main Belt Comets, MBCs) have attracted a great deal of interest. Given that sublimation of volatile material (presumably water-ice) drives MBC activity, these bodies are probable candidates for delivering a significant amount of Earth's water. Dynamical studies suggest in-situ formation of MBCs as the remnants of the break-up of large icy asteroids. Also, collisions between MBCs and small objects might have exposed sub-surface water-ice triggering the cometary activity of these bodies. In order to advance the effort of understanding the nature of MBC activation, we have investigated these collision processes by simulating the impacts in detail using a smooth particle hydrodynamics (SPH) approach that includes material strength and fracture models. Our simulations cover a range of impact velocities (between 0.5 km/s and 5.3 km/s) and angles, allowing m-sized impactors to erode enough of an MBC's surface to expose volatiles and trigger its activation. We also varied the material strength of the active asteroid's surface to study its influence on crater depths and shapes. As expected, depending on the impact energy, impact angle, and MBC's material strength we observe different crater depths. Across all scenarios however, our results show that the crater depths do not exceed a few meters. This implies that if the activity of MBCs is due to sublimating water-ice, ice has to exist in no deeper than a few meters from the surface.

  13. Meningococcal carriage in the African meningitis belt

    Science.gov (United States)

    2013-01-01

    A meningococcal serogroup A polysaccharide/tetanus toxoid conjugate vaccine (PsA-TT) (MenAfriVac#x2122;) is being deployed in countries of the African meningitis belt. Experience with other polysaccharide/protein conjugate vaccines has shown that an important part of their success has been their ability to prevent the acquisition of pharyngeal carriage and hence to stop transmission and induce herd immunity. If PsA-TT is to achieve the goal of preventing epidemics, it must be able to prevent the acquisition of pharyngeal carriage as well as invasive meningococcal disease and whether PsA-TT can prevent pharyngeal carriage needs to be determined. To address this issue, a consortium (the African Meningococcal Carriage (MenAfriCar) consortium) was established in 2009 to investigate the pattern of meningococcal carriage in countries of the African meningitis belt prior to and after the introduction of PsA-TT. This article describes how the consortium was established, its objectives and the standardised field and laboratory methods that were used to achieve these objectives. The experience of the MenAfriCar consortium will help in planning future studies on the epidemiology of meningococcal carriage in countries of the African meningitis belt and elsewhere. Un vaccin conjugué contenant un polysaccharide du sérogroupe A méningococcique et une anatoxine du tétanos (PsA-TT) (MenAfriVac™) est en cours de déploiement dans les pays de la ceinture africaine de la méningite. L’ expérience avec d’ autres vaccins conjugués polysaccharide/protéine a montré qu’ une partie importante de leur succès a été leur capacité à empêcher l’ acquisition du portage pharyngé et donc à arrêter la transmission et à induire une immunité de group. Si PsA-TT doit d’ atteindre l’ objectif de prévenir les épidémies, il devrait être en mesure d’ empêcher l’ acquisition du portage pharyngé ainsi que la méningococcie invasive et le fait que PsA-TT puisse emp

  14. Meningococcal carriage in the African meningitis belt

    Science.gov (United States)

    2013-01-01

    A meningococcal serogroup A polysaccharide/tetanus toxoid conjugate vaccine (PsA-TT) (MenAfriVac#x2122;) is being deployed in countries of the African meningitis belt. Experience with other polysaccharide/protein conjugate vaccines has shown that an important part of their success has been their ability to prevent the acquisition of pharyngeal carriage and hence to stop transmission and induce herd immunity. If PsA-TT is to achieve the goal of preventing epidemics, it must be able to prevent the acquisition of pharyngeal carriage as well as invasive meningococcal disease and whether PsA-TT can prevent pharyngeal carriage needs to be determined. To address this issue, a consortium (the African Meningococcal Carriage (MenAfriCar) consortium) was established in 2009 to investigate the pattern of meningococcal carriage in countries of the African meningitis belt prior to and after the introduction of PsA-TT. This article describes how the consortium was established, its objectives and the standardised field and laboratory methods that were used to achieve these objectives. The experience of the MenAfriCar consortium will help in planning future studies on the epidemiology of meningococcal carriage in countries of the African meningitis belt and elsewhere. Un vaccin conjugué contenant un polysaccharide du sérogroupe A méningococcique et une anatoxine du tétanos (PsA-TT) (MenAfriVac™) est en cours de déploiement dans les pays de la ceinture africaine de la méningite. L’ expérience avec d’ autres vaccins conjugués polysaccharide/protéine a montré qu’ une partie importante de leur succès a été leur capacité à empêcher l’ acquisition du portage pharyngé et donc à arrêter la transmission et à induire une immunité de group. Si PsA-TT doit d’ atteindre l’ objectif de prévenir les épidémies, il devrait être en mesure d’ empêcher l’ acquisition du portage pharyngé ainsi que la méningococcie invasive et le fait que PsA-TT puisse emp

  15. Noninvasive brain stimulation by radioelectric asymmetric conveyor in the treatment of agoraphobia: open-label, naturalistic study

    Directory of Open Access Journals (Sweden)

    Mannu P

    2011-11-01

    Full Text Available Piero Mannu, Salvatore Rinaldi, Vania Fontani, Alessandro Castagna, Matteo Lotti MargottiDepartment of Neuro Psycho Physio Pathology, Rinaldi Fontani Institute, Florence, ItalyBackground: Agoraphobia is considered to be the most serious complication of panic disorder. It involves progressive development of debilitating anxiety symptoms related to being in situations where one would be extremely embarrassed and could not be rescued in the case of a panic attack. This study aimed to investigate the efficacy of noninvasive brain stimulation using a radioelectric asymmetric conveyor (REAC for agoraphobia.Patients and methods: Twenty-three patients (3 males and 20 females suffering from agoraphobia and without a history of panic disorder were evaluated by a psychiatrist using the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision, and the Agoraphobia Scale (AS. The patients were subjected to two 18-session cycles of noninvasive brain stimulation with the REAC, according to an established therapeutic protocol called neuro-psycho-physical optimization.Results: Analyzing the anxiety and avoidance parameters of the AS after the first and second cycles of REAC treatment revealed variation in levels of response to treatment, including weak (AS item 7, moderate (AS items 10 and 13, and good responses (AS items 1–6, 8, 9, 11, 12, and 14–20.Conclusion: These results highlight the potential of the REAC to treat complex clinical situations such as agoraphobia, which is typically resistant to pharmacologic treatments. Furthermore, these data show the advantages of REAC treatment, even compared with modern cognitive behavioral therapy, including a relatively rapid and “stable” clinical response (just over 6 months and economic cost.Keywords: anxiety, avoidance, fear, REAC

  16. Conveyor Cultivation of the Halophytic Plant Salicornia europaea for the Recycling of NaCl from Human Liquid Waste in a Biological Life Support System.

    Science.gov (United States)

    Balnokin, Yurii; Myasoedov, Nikolay; Popova, Larissa; Tikhomirov, Alexander A.; Ushakova, Sofya; Tikhomirova, Natalia; Lasseur, Christophe; Gros, Jean-Bernard

    One problem in designing bioregenerative life support systems (BLSS) is developing technolo-gies to include human liquid and solid waste in intrasystem recycling. A specific task is recycling of NaCl excreted in urine by humans. We showed recently that this could be achieved through inclusion of the salt accumulating halophyte Salicornia europaea in the autotrophic compart-ment of the BLSS (Balnokin et al., ASR, 2010, in press). A model of NaCl circulation in BLSS with inclusion of S. europaea was based on the NaCl turnover in the human -urine -nutrient solution -S. europaea -human cycle. Mineralized urine was used as a basis for preparation of a nutrient solution for the halophyte cultivation. The shoots of the halophyte cultivated in the mineralized urine and containing NaCl could to be used by the BLSS inhabitants in their diets. In this report we describe cultivation of S. europaea which allows turnover of NaCl and produces daily shoot biomass containing Na+ and Cl- in quantities approximately equal to those excreted in daily human urine. The plants were grown in water culture in a climatic chamber under controlled conditions. A solution simulating mineralized urine (SSMU) was used as a basis for preparation of a nutri-ent solution for S. europaea cultivation. For continuous biomass production, seedlings of S. europaea, germinated preliminary in moist sand, were being transferred to the nutrient solu-tion at regular intervals (every two days). Duration of the conveyor operation was 112 days. During the first 56 days, the seedlings were being planted in SSMU diluted by a factor of 1.5 (2/3 SSMU). The same solution was introduced into the growth vessels as volumes of growth medium decreased due to plant transpiration. Starting from the 56th day as conveyor operation was initiated, the plants were being harvested every two days; the solutions from the discharged vessels were mixed with the fresh SSMU and the mixture was introduced into all other growth vessels of

  17. Digital Spectra and Analysis of Altitudinal Belts in Tianshan Mountains,China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Baiping; MO Shenguo; WU Hongzhi; XIAO Fei

    2004-01-01

    Based on the framework of the geo-info spectra of montane altitudinal belts, this paper firstly reviews six classification systems for the spectra of mountain altitudinal belts in China and considers that detailed regional study of altitudinal belts is the key for reaching standardization and systemization of mountain altitudinal belts. Only can this furtheridentify and resolve problems with the study of altitudinal belts. The factors forming the spectra of altitudinal belts are analyzed in the Tianshan Mountains of China, and a digital altitudinal belt system is constructed for the northern flank, Southern flank, the heartland, and Ilivalley in the west. The characteristics of each belt are revealed with a summarization of the pattern of areal differentiation of altitudinal belts.

  18. A Physical Model of Electron Radiation Belts of Saturn

    Science.gov (United States)

    Lorenzato, L.; Sicard-Piet, A.; Bourdarie, S.

    2012-04-01

    Radiation belts causes irreversible damages on on-board instruments materials. That's why for two decades, ONERA proposes studies about radiation belts of magnetized planets. First, in the 90's, the development of a physical model, named Salammbô, carried out a model of the radiation belts of the Earth. Then, for few years, analysis of the magnetosphere of Jupiter and in-situ data (Pioneer, Voyager, Galileo) allow to build a physical model of the radiation belts of Jupiter. Enrolling on the Cassini age and thanks to all information collected, this study permits to adapt Salammbô jovian radiation belts model to the case of Saturn environment. Indeed, some physical processes present in the kronian magnetosphere are similar to those present in the magnetosphere of Jupiter (radial diffusion; interaction of energetic electrons with rings, moons, atmosphere; synchrotron emission). However, some physical processes have to be added to the kronian model (compared to the jovian model) because of the particularity of the magnetosphere of Saturn: interaction of energetic electrons with neutral particles from Enceladus, and wave-particle interaction. This last physical process has been studied in details with the analysis of CASSINI/RPWS (Radio and Plasma Waves Science) data. The major importance of the wave particles interaction is now well known in the case of the radiation belts of the Earth but it is important to investigate on its role in the case of Saturn. So, importance of each physical process has been studied and analysis of Cassini MIMI-LEMMS and CAPS data allows to build a model boundary condition (at L = 6). Finally, results of this study lead to a kronian electrons radiation belts model including radial diffusion, interactions of energetic electrons with rings, moons and neutrals particles and wave-particle interaction (interactions of electrons with atmosphere particles and synchrotron emission are too weak to be taken into account in this model). Then, to

  19. 多功能马铃薯清选输送机的设计%Design on Multi-functional Potato Cleaning Conveyor

    Institute of Scientific and Technical Information of China (English)

    李学强; 卢延芳; 苏国粱; 魏忠彩; 王法明; 孙传祝

    2016-01-01

    With the aim to solve the problems of slow development of potato cleaning and conveying equipment, so as seriously restricting the potato planting industry, a kind of multi-functional potato cleaning conveyor was designed. The scarification wheels stirred and rubbed the mixture of potato when the mixture of potato, soil and debris transported above the cleaning device, and lost the soil adhereing to the potato. And then the mixture was transported to the cleaning roller to clean gradu-ally. The cleared soil fell from the gap between cleaning roller to the soil conveyor; when the cleaned potato was conveyed above the sorting device, the potatoes smaller than the gap between the rolls fell to the small potato conveyor, and the big potatoes crossed the roll and fell to the big potato conveyor. A kind of multi-functional potato cleaning conveyer with clean-ing, sorting, multiway conveying and loading was provided, which had a great significance for solving the labor shortage and promoting the development of potato planting industry.%针对国内马铃薯清选输送设备发展缓慢、严重制约马铃薯种植业的发展等问题,设计了一种多功能马铃薯清选输送机.当马铃薯和泥土及杂物的混合物输送到清选装置上方时,各松土轮即对马铃薯的混合物进行搅动和揉搓,使粘着在马铃薯上的泥土松动后,再输送到各清选辊上逐步清选,清除的泥土从各清选辊之间的缝隙落入泥土输送机上;清选干净的马铃薯被输送到分选装置上方时,小于两分选辊之间缝隙的小马铃薯落入小薯输送机上,大马铃薯则越过分选辊后落入大薯输送机上.本研究为马铃薯种植户提供了一款集清选、分选、多向输送和装载于一体的多功能马铃薯清选输送机,对解决农忙时节用工荒,推进马铃薯种植业的发展具有重要意义.

  20. Evolution of the Bhandara-Balaghat granulite belt along the southern margin of the Sausar Mobile Belt of central India

    Indian Academy of Sciences (India)

    H M Ramachandra; Abhinaba Roy

    2001-12-01

    The Bhandara-Balaghat granulite (BBG) belt occurs as a 190 km long, detached narrow, linear, NE-SW to ENE-WSW trending belt that is in tectonic contact on its northern margin with the Sausar Group of rocks and is bordered by the Sakoli fold belt in the south. The Bhandara part of the BBG belt is quite restricted, comprising a medium to coarse grained two-pyroxene granulite body that is of gabbroic composition and preserves relic igneous fabric. The main part of the belt in Arjuni-Balaghat section includes metasedimentary (quartzite, BIF, Al- and Mg-Al metapelites) and metaigneous (metaultramafic, amphibolite and two-pyroxene granulite) protoliths interbanded with charnockite and charnockitic gneiss. These rocks, occurring as small bands and enclaves within migmatitic and granitic gneisses, show polyphase deformation and metamorphism. Geochemically, basic compositions show tholeiitic trend without Fe-enrichment, non-komatitic nature, continental affinity and show evolved nature. Mineral parageneses and reaction textures in different rock compositions indicate early prograde, dehydration melt forming reactions followed by orthopyroxene stability with or without melt. Coronitic and symplectitic garnets have formed over earlier minerals indicating onset of retrograde IBC path. Evidences for high temperature ductile shearing are preserved at places. Retrogressive hydration events clearly post-date the above paths. The present study has shown that the BBG belt may form a part of the Bastar Craton and does not represent exhumed oceanic crust of the Bundelkhand Craton. It is further shown that rocks of the BBG belt have undergone an earlier high-grade granulite metamorphism at 2672 ± 54 Ma (Sm-Nd age) and a post-peak granulite metamorphism at 1416 ± 59 Ma (Sm-Nd age, 1380 ± 28 Ma Rb-Sr age). These events were followed by deposition of the Sausar supracrustals and Neoproterozoic Sausar orogeny between 973 ± 63 Ma and 800 ± 16 Ma (Rb-Sr ages).

  1. Rotationally driven 'zebra stripes' in Earth's inner radiation belt.

    Science.gov (United States)

    Ukhorskiy, A Y; Sitnov, M I; Mitchell, D G; Takahashi, K; Lanzerotti, L J; Mauk, B H

    2014-03-20

    Structured features on top of nominally smooth distributions of radiation-belt particles at Earth have been previously associated with particle acceleration and transport mechanisms powered exclusively by enhanced solar-wind activity. Although planetary rotation is considered to be important for particle acceleration at Jupiter and Saturn, the electric field produced in the inner magnetosphere by Earth's rotation can change the velocity of trapped particles by only about 1-2 kilometres per second, so rotation has been thought inconsequential for radiation-belt electrons with velocities of about 100,000 kilometres per second. Here we report that the distributions of energetic electrons across the entire spatial extent of Earth's inner radiation belt are organized in regular, highly structured and unexpected 'zebra stripes', even when the solar-wind activity is low. Modelling reveals that the patterns are produced by Earth's rotation. Radiation-belt electrons are trapped in Earth's dipole-like magnetic field, where they undergo slow longitudinal drift motion around the planet because of the gradient and curvature of the magnetic field. Earth's rotation induces global diurnal variations of magnetic and electric fields that resonantly interact with electrons whose drift period is close to 24 hours, modifying electron fluxes over a broad energy range into regular patterns composed of multiple stripes extending over the entire span of the inner radiation belt. PMID:24646996

  2. JOVIAN EARLY BOMBARDMENT: PLANETESIMAL EROSION IN THE INNER ASTEROID BELT

    Energy Technology Data Exchange (ETDEWEB)

    Turrini, D.; Coradini, A.; Magni, G., E-mail: diego.turrini@ifsi-roma.inaf.it [Istituto di Astrofisica e Planetologia Spaziali, INAF-IAPS, Via Fosso del Cavaliere 100, 00133, Rome (Italy)

    2012-05-01

    The asteroid belt is an open window on the history of the solar system, as it preserves records of both its formation process and its secular evolution. The progenitors of the present-day asteroids formed in the Solar Nebula almost contemporary to the giant planets. The actual process producing the first generation of asteroids is uncertain, strongly depending on the physical characteristics of the Solar Nebula, and the different scenarios produce very diverse initial size-frequency distributions (SFDs). In this work, we investigate the implications of the formation of Jupiter, plausibly the first giant planet to form, on the evolution of the primordial asteroid belt. The formation of Jupiter triggered a short but intense period of primordial bombardment, previously unaccounted for, which caused an early phase of enhanced collisional evolution in the asteroid belt. Our results indicate that this Jovian Early Bombardment caused the erosion or the disruption of bodies smaller than a threshold size, which strongly depends on the SFD of the primordial planetesimals. If the asteroid belt was dominated by planetesimals less than 100 km in diameter, the primordial bombardment would have caused the erosion of bodies smaller than 200 km in diameter. If the asteroid belt was instead dominated by larger planetesimals, the bombardment would have resulted in the destruction of bodies as big as 500 km.

  3. Flat belt continuously variable high speed drive. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kumm, E.L.

    1992-02-01

    A study was undertaken at Kumm Industries funded by DOE in the NBS/DOE Energy-Related Inventions Program starting in August 1990 to design, construct and test a novel very high speed flat belt drive. The test arrangement as shown in Figure 1 consists of a multiple belt-pulley configuration that transmits power from a low speed (2000--4000 RPM) input to a small pulley ``turbine`` (27,000 to 55,000 RPM) and then to the low speed output variable radius pulley (2000--5000 RPM) via a special self-active tensioner. Transmitting 25 HP to and from the ``turbine`` corresponds to obtaining 50 HP in one direction only in a possible turbo compounded engine application. The high speed of the ``turbine`` belts, i.e. 100 meters/sec. at 55,000 RPM, while transferring substantial power is a new much higher operating regime for belts. The study showed that the available belts gave overall test rig efficiencies somewhat above 80% for the higher speeds (50,000 RPM) and higher powers (corresponding to above 90% in the turbocompound application) and a significantly better efficiencies at slightly lower speeds. The tests revealed a number of improved approaches in the design of such high speed drives. It appears that there is considerable possibility for further improvement and application of such equipment.

  4. 盾构螺旋输送机驱动密封故障处理与防护技术%Countermeasures for Malfunctions of Drive Sealing of Screw Conveyors of Shield Machines

    Institute of Scientific and Technical Information of China (English)

    吴朝来

    2012-01-01

    The causes for the malfunctions of the drive sealing of screw conveyors of shield machines, such as irrational screw conveyor design, inclining of screw rod, damage of contacting surface of the screw conveyor case, leaping forward of the screw rod and inadequate grease injection, are analyzed, and countermeasures, including screw conveyor structure optimization, ground conditioning, rationally selecting the screw conveyor speed, avoiding boring with empty chamber and controlling the manufacturing process, are proposed, with the practice in Chongqing as an example. The paper can provide reference for the coping with the malfunctions of the drive sealing of screw conveyors of shield machines in similar projects in the future.%为解决盾构螺旋机驱动密封故障问题,以重庆地区盾构施工情况为依托,结合多台盾构螺旋输送机驱动密封的修复经验,重点分析螺旋输送机驱动密封产生故障的原因:螺旋机设计不合理、螺旋机螺杆倾斜、筒体连接面磨损、螺杆向前蹿动、油脂注入量不足。总结出新的故障处理(螺旋机结构优化、渣土改良、合理选择螺旋机转速、防止空仓掘进、严控加工工艺等)与预防措施(螺旋机叶片修复、改善油脂注入量、更换损坏部件)。为今后盾构施工中处理螺旋输送机驱动密封故障处理与防护技术提供依据。

  5. Aqueous alteration on main-belt asteroids

    Science.gov (United States)

    Fornasier, S.; Lantz, C.; Barucci, M.; Lazzarin, M.

    2014-07-01

    The study of aqueous alteration is particularly important for unraveling the processes occurring during the earliest times in Solar System history, as it can give information both on the thermal processes and on the localization of water sources in the asteroid belt, and for the associated astrobiological implications. The aqueous alteration process produces the low temperature (< 320 K) chemical alteration of materials by liquid water which acts as a solvent and produces materials like phyllosilicates, sulphates, oxides, carbonates, and hydroxides. This means that liquid water was present in the primordial asteroids, produced by the melting of water ice by heating sources, very probably by ^{26}Al decay. Hydrated minerals have been found mainly on Mars surface, on primitive main-belt asteroids (C, G, B, F, and P-type, following the classification scheme by Tholen, 1984) and possibly also on few transneptunian objects. Reflectance spectroscopy of aqueous altered asteroids shows absorption features in the 0.6-0.9 and 2.5-3.5-micron regions, which are diagnostic of, or associated with, hydrated minerals. In this work, we investigate the aqueous alteration process on a large sample of 600 visible spectra of C-complex asteroids available in the literature. We analyzed all these spectra in a similar way to characterize the absorption-band parameters (band center, depth, and width) and spectral slope, and to look for possible correlations between the aqueous alteration process and the asteroids taxonomic classes, orbital elements, heliocentric distances, albedo, and sizes. We find that 4.6 % of P, 7.7 % of F, 9.8 % of B, 50.5 % of C, and 100 % of the G-type asteroids have absorption bands in the visible region due to hydrated silicates. Our analysis shows that the aqueous alteration sequence starts from the P-type objects, practically unaltered, and increases through the P → F → B → C → G asteroids, these last being widely aqueously altered, strengthening thus

  6. Two new basaltic asteroids in the Outer Main Belt

    CERN Document Server

    Duffard, R

    2007-01-01

    The identification of other basaltic objects in the asteroid belt is mandatory to explain the diversity in the collection of basaltic meteorites. This diversity requires more than one differentiated parent body, a fact that is consistent with the diversity of differentiated parent bodies implied by the iron meteorites. Based on a list of previously identified candidate basaltic (V-type) asteroids, two asteroids in the outer main belt, (7472) Kumakiri and (10537) 1991 RY16, were spectroscopically observed during an observational run in Calar Alto Observatory, Spain. We confirm the V-type character of these two asteroids that, together with (1459) Magnya, become the only known traces of basaltic found in the outer main belt up to now. We also demonstrate that the searching for candidate V-type asteroids using a photometric survey, like the Sloan Digital Sky Survey, produces reliable results.

  7. Gravity inferred subsurface structure of Gadwal Schist belt, Andhra Pradesh

    Indian Academy of Sciences (India)

    G Ramadass; I B Ramaprasada Rao; N Srinivasulu

    2001-03-01

    Detailed gravity data collected across the Gadwal schist belt in the state of Andhra Pradesh show an 8.4 mgal residual gravity anomaly associated with meta-sediments/volcanics of the linear NNW-SSE trending schist belt that shows metamorphism from green schist to amphibolite facies. This schist belt is flanked on either side by the peninsular gneissic complex. The elevation and slab Bouguer corrected residual gravity profile data were interpreted using 2-D prism models. The results indicate a synformal structure having a width of 1.8 km at the surface, tapering at a depth of about 2.6 km with a positive density contrast of 0.15 gm/cc with respect to the surrounding peninsular gneissic complex.

  8. Regional Fault Systems of Qaidam Basin and Adjacent Orogenic Belts

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The purpose of this paper is to analyze the regional fault systems of Qaidam basin and adjacent orogenic belts. Field investigation and seismic interpretation indicate that five regional fault systems occurred in the Qaidam and adjacent mountain belts, controlling the development and evolution of the Qaidam basin. These fault systems are: (1)north Qaidam-Qilian Mountain fault system; (2) south Qaidam-East Kunlun Mountain fault system; (3)Altun strike-slip fault system; (4)Elashan strike-slip fault system, and (5) Gansen-Xiaochaidan fault system. It is indicated that the fault systems controlled the orientation of the Qaidam basin, the formation and distribution of secondary faults within the basin,the migration of depocenters and the distribution of hydrocarbon accumulation belt.

  9. Relativistic surfatron process for Landau resonant electrons in radiation belts

    CERN Document Server

    Osmane, A

    2014-01-01

    Recent theoretical studies of the nonlinear wave-particle interactions for relativistic particles have shown that Landau resonant orbits could be efficiently accelerated along the mean background magnetic field for propagation angles $\\theta$ in close proximity to a critical propagation $\\theta_\\textrm{c}$ associated with a Hopf--Hopf bifurcation condition. In this report, we extend previous studies to reach greater modeling capacities for the study of electrons in radiation belts by including longitudinal wave effects and inhomogeneous magnetic fields. We find that even though both effects can limit the surfatron acceleration of electrons in radiation belts, gains in energy of the order of 100 keV, taking place on the order of ten milliseconds, are sufficiently strong for the mechanism to be relevant to radiation belt dynamics.

  10. The Belt voice: Acoustical measurements and esthetic correlates

    Science.gov (United States)

    Bounous, Barry Urban

    This dissertation explores the esthetic attributes of the Belt voice through spectral acoustical analysis. The process of understanding the nature and safe practice of Belt is just beginning, whereas the understanding of classical singing is well established. The unique nature of the Belt sound provides difficulties for voice teachers attempting to evaluate the quality and appropriateness of a particular sound or performance. This study attempts to provide answers to the question "does Belt conform to a set of measurable esthetic standards?" In answering this question, this paper expands on a previous study of the esthetic attributes of the classical baritone voice (see "Vocal Beauty", NATS Journal 51,1) which also drew some tentative conclusions about the Belt voice but which had an inadequate sample pool of subjects from which to draw. Further, this study demonstrates that it is possible to scientifically investigate the realm of musical esthetics in the singing voice. It is possible to go beyond the "a trained voice compared to an untrained voice" paradigm when evaluating quantitative vocal parameters and actually investigate what truly beautiful voices do. There are functions of sound energy (measured in dB) transference which may affect the nervous system in predictable ways and which can be measured and associated with esthetics. This study does not show consistency in measurements for absolute beauty (taste) even among belt teachers and researchers but does show some markers with varying degrees of importance which may point to a difference between our cognitive learned response to singing and our emotional, more visceral response to sounds. The markers which are significant in determining vocal beauty are: (1) Vibrancy-Characteristics of vibrato including speed, width, and consistency (low variability). (2) Spectral makeup-Ratio of partial strength above the fundamental to the fundamental. (3) Activity of the voice-The quantity of energy being produced. (4

  11. Cold bonding sewing up repairing technology for flame-retardant solid woven conveyor belt%阻燃整芯输送带冷粘缝合修复技术

    Institute of Scientific and Technical Information of China (English)

    杨景才; 贾剑珉; 葛长淮; 于广顺; 刘勇; 张巨清

    2003-01-01

    对纵向边部撕裂宽度达300 mm的芬纳公司产10级PVG阻燃整芯输送带进行了冷粘缝合修复.修复时采用了PVC输送带粘合专用高强度柔性结构胶(简称116胶),粘合部位设计为斜面粘合结构,施工中采用粘合面加压吻后低温硫化(80 ℃×6 h)的方法.冷粘缝合修复后的PVG阻燃整芯输送带基本可满足正常生产要求.

  12. Make selection for the position of the second head in double-drive-head belt conveyor%双机头驱动带式输送机第2机头位置的选定

    Institute of Scientific and Technical Information of China (English)

    石同利; 李军鸿

    2004-01-01

    根据煤矿平巷运输的生产实际,针对双机头驱动带式输送机第2机头位置选定的原则及计算方法进行了探讨,以运行阻力为计算依据,以输送带传动的欧拉公式为基本理论,以对阻力的合理分配为选定原则,介绍了2种确定方法,得出第2机头距机尾距离占运输全长35%的结论.

  13. 长距离重载胶带输送机提速与能耗的关系%Relationship between the Speed Increase and Energy Consumption for Long Distance Heavy Belt Conveyor

    Institute of Scientific and Technical Information of China (English)

    陈立志; 刘文英; 党琪

    2014-01-01

    量化分析速度对胶带输送机主要阻力各分量的影响,指出学者们两种对立的观点.采用提速增加能耗的保守理论计算秦皇岛港煤三期胶带输送机实例,结论是对长距离重载胶带输送机,只提速可能会使能耗有限度增加,辅之以改变托辊直径或布置方式等其它措施后,能耗将会下降.

  14. Application of the Technique on Switcher Synchronous Following Belt Conveyor%胶带输送机与开关同步跟进技术的设计与应用

    Institute of Scientific and Technical Information of China (English)

    陈丽青

    2006-01-01

    在综采工作面采煤过程中,当遇到地质条件恶劣、炸帮煤及支柱多等情况时,利用胶带输送机与开关同步跟进技术是行之有效的手段,为实现工作面的顺利开采提供了宝贵的经验.

  15. Implement of a Large-scale Belt Conveyor HARRISON-start with 6RA70%大型带式输送机HARRISON起动6RA70的实现

    Institute of Scientific and Technical Information of China (English)

    丁黎梅; 张海; 高磊鸿; 杨津听; 蔡莲如

    2006-01-01

    介绍了大型胶带机理想的HARRISON起动方式以及HARRISON起动方式的数学模型,介绍了高性能的6RA70全数字直流调速装置,并利用其内嵌的数学运算模块实现了HARRISON起动,详细阐述了HARRISON起动的实现原理.

  16. Thermal-structure Coupling Analysis of Disc Brake of Conveyor Belt%带式输送机盘式制动器热结构耦合分析

    Institute of Scientific and Technical Information of China (English)

    张杰; 李军霞

    2016-01-01

    揭示了盘式制动器的热结构耦合过程,分析了盘式制动器的热传导过程并建立了温度场的数学模型.利用Workbench有限元分析软件进行了制动过程的仿真和模拟,揭示了应力场、应变场以及温度场的分布情况与变化规律,并在不同的初始条件下做了对比分析,从而为盘式制动器的优化设计和改进提供了理论依据.

  17. DTL长距离弯曲带式输送机在选煤厂的应用%Application on DTL Long Bending Belt Conveyor in the Coal Preparation Plant

    Institute of Scientific and Technical Information of China (English)

    翟中朝

    2013-01-01

    DTL长距离弯曲带式输送机在斜沟煤矿选煤厂的成功应用,缩减了矸石在长距离运输过程中的转运环节.设备维护更加方便,降低了设备故障率,减少了设备的维护量.使工艺系统的布置更灵活、简捷、紧凑,便于生产管理.取得了直接和间接的经济效益,并在使用过程中取得了良好效果.通过对弯曲皮带输送机在该厂的成功应用进行研究,使该项技术在受地形制约及需长距离运输的选煤厂建设中得到广泛的应用.

  18. 基于COSMOS/Works的带式输送机传动滚筒的有限元分析%Finite Element Analysis of Driving Drum of Belt Conveyor Based on COSMOS/Works

    Institute of Scientific and Technical Information of China (English)

    李晓丽; 袁圆

    2010-01-01

    对输送机传动滚筒受力状况做了理论分析,运用有限元分析软件COSMOS/Works对传动滚筒进行了静力分析,得出滚筒在载荷作用下的应力和变形分布规律.分析结果表明,该传动滚筒的结构设计完全满足其强度、刚度要求.

  19. Finite Element Analysis of Expanding Sleeve Connection of Belt Conveyor Based on COSMOS/Works%基于COSMOS/Works的带式输送机胀套联接的有限元分析

    Institute of Scientific and Technical Information of China (English)

    陆悌元; 郭永存; 胡坤

    2010-01-01

    胀套联接作为带式输送机中滚筒轴与轮毂之间的一种联接形式,具有其自身的优越性.通过建立胀套的有限元模型,利用COSMOS/Works插件的接触分析功能来检查胀套及其所联接的滚筒轴的应力和变形情况,从而选择合适的滚筒轴和确保其安装的精确性.并在此基础上比较胀套与其他联接的优缺点.

  20. MTD1200型薄煤层胶带机自移机尾的设计%Design on self moved tail of MTD 1200 thin seam belt conveyor

    Institute of Scientific and Technical Information of China (English)

    王赟

    2009-01-01

    阐述了研发设计薄煤层顺槽运输设备胶带机自移机尾的必要性,以MTD1200型胶带机自移机尾为例,对其结构布局和设计中的关键问题进行了综合分析,介绍了该设备的主要技术参数和性能特点,为薄煤层胶带机自移机尾的研发进行了有益探索.

  1. Traffic restrictions due to wind on the Fehmarn Belt bridge

    DEFF Research Database (Denmark)

    Dellwik, E.; Mann, Jakob; Rosenhagen, G.

    2006-01-01

    This report documents the calculations carried out in order to estimate the wind climate at the site where the Fehmarn Belt bridge is planned. Further, an estimate of how often and for how long traffic restrictions will be enforced according to statedcriteria (sec. 3.2) is given. This estimate...... are the same as used in this report and here the comparison is satisfactory. We estimate that the prospective Fehmarn Belt bridge will be closed roughly 2% of the timefor light roadway vehicles (unloaded trucks and caravans), corresponding to 7 days per year. This is slightly less than for the Fehmarnsund...

  2. Bifurcation for Dynamical Systems of Planet-Belt Interaction

    OpenAIRE

    Jiang, Ing-Guey; Yeh, Li-Chin

    2002-01-01

    The dynamical systems of planet-belt interaction are studied by the fixed-point analysis and the bifurcation of solutions on the parameter space is discussed. For most cases, our analytical and numerical results show that the locations of fixed points are determined by the parameters and these fixed points are either structurally stable or unstable. In addition to that, there are two special fixed points: the one on the inner edge of the belt is asymptotically stable and the one on the outer ...

  3. Improvement Design of Tension Device for Tail of Scraper Conveyor%刮板运输机机尾张紧装置的改进

    Institute of Scientific and Technical Information of China (English)

    敖剑忠; 敖金龙

    2014-01-01

    坪湖矿洗煤厂的刮板运输机尾张紧调节通常采用丝杆-滑块拉紧装置,其所处环境差,设备易腐蚀,使得机尾调节难度较大,严重影响设备的正常使用,给设备运行留下了安全隐患。洗煤厂根据自身条件对设备进行改进,研制出蜗轮蜗杆减速器张紧装置,使得机尾调节变得安全、方便、快捷,获得了成功应用。%The lead-screw -slider tension device used to be used in tension adjustment for the tail of scraper conveyor in Pinghu Coal Washing Plant .The poor environmental conditions and perishable equipment made the tail adjustment difficult ,which seriously affected the normal use of equipment and left safety hazards for equip-ment running .The paper presents the improvement design of tension device for the tail of scraper conveyor , which has made the tail adjustment safe ,convenient and fast .

  4. Análisis de la fuerza axial en un transportador de sinfín // Analysis of axial force in a screw conveyor.

    Directory of Open Access Journals (Sweden)

    F. Aguilar Parés

    1999-01-01

    Full Text Available Durante el movimiento de un material en un transportador de sinfín surge una fuerza en dirección axial que influye en laselección de uno de los cojinetes de apoyo del equipo. En el artículo aparecen algunas soluciones constructivas que tienen encuentan la fuerza axial. Por otro lado se establece la relación entre la fuerza axial y el empuje axial y se precisa de quiendepende el sentido del empuje axial. Por último se propone un modelo matemático que relaciona la fuerza axial con la potenciarequerida por el equipo.Palabras claves: Transportador de sinf in, fuerza axial , empuje axial ._________________________________________________________________________AbstractDuring the movement of material in a screw conveyor surge a force in axial direction that influence in the selection of one ofthe equipment support bearings. Some constructive solutions appear in the article for considering the axial force. In the otherhand it is established the relation between axial force and axial thurst and it is precised whose direction thurst axial depend of.Finally it is proposed a mathematic model that relates the axial force with the power required by the equipment.Key words: Screw conveyor, axial force, axial thurst .

  5. Development of Parameter Design System of Screw Conveyor%螺旋输送机参数设计系统的开发

    Institute of Scientific and Technical Information of China (English)

    刘海军; 孙井坤; 郑先哲

    2012-01-01

    Parameter design of screw conveyor was realized according to the computation model of screw convey or parameters on platform of Visual Basic 6.0 with object oriented programming. Overall function of system, design of process, and the implementation technique of every functional module were discussed. Developing and running environment of the system were introduced. Parameters according with different working conditions can be designed using the system, which makes design work of screw conveyor fast and exact.%根据螺旋输送机参数计算的数学模型,在Visual Basic6.0的平台下,利用面向对象的程序设计,实现了螺旋输送机的参数计算设计。讨论了系统总体功能及流程的设计以及各主要功能模块的实现技术,并阐述了系统的开发和运行环境。该系统能够设计出符合不同工作条件的螺旋输送机参数,使螺旋输送机的设计工作快速、准确。

  6. Design study of flat belt CVT for electric vehicles

    Science.gov (United States)

    Kumm, E. L.

    1980-01-01

    A continuously variable transmission (CVT) was studied, using a novel flat belt pulley arrangement which couples the high speed output shaft of an energy storage flywheel to the drive train of an electric vehicle. A specific CVT arrangement was recommended and its components were selected and sized, based on the design requirements of a 1700 KG vehicle. A design layout was prepared and engineering calculations made of component efficiencies and operating life. The transmission efficiency was calculated to be significantly over 90% with the expected vehicle operation. A design consistent with automotive practice for low future production costs was considered, together with maintainability. The technology advancements required to develop the flat belt CVT were identified and an estimate was made of how the size of the flat belt CVT scales to larger and smaller design output torques. The suitability of the flat belt CVT for alternate application to an electric vehicle powered by an electric motor without flywheel and to a hybrid electric vehicle powered by an electric motor with an internal combustion engine was studied.

  7. Resolving the Planetesimal Belt of HR 8799 with ALMA

    CERN Document Server

    Booth, Mark; Casassus, Simon; Hales, Antonio S; Dent, William R F; Faramaz, Virginie; Matrà, Luca; Barkats, Denis; Brahm, Rafael; Cuadra, Jorge

    2016-01-01

    The star HR 8799 hosts one of the largest known debris discs and at least four giant planets. Previous observations have found evidence for a warm belt within the orbits of the planets, a cold planetesimal belt beyond their orbits and a halo of small grains. With the infrared data, it is hard to distinguish the planetesimal belt emission from that of the grains in the halo. With this in mind, the system has been observed with ALMA in band 6 (1.34 mm) using a compact array format. These observations allow the inner edge of the planetesimal belt to be resolved for the first time. A radial distribution of dust grains is fitted to the data using an MCMC method. The disc is best fit by a broad ring between $145^{+12}_{-12}$ AU and $429^{+37}_{-32}$ AU at an inclination of $40^{+5}_{-6}${\\deg} and a position angle of $51^{+8}_{-8}${\\deg}. A disc edge at ~145 AU is too far out to be explained simply by interactions with planet b, requiring either a more complicated dynamical history or an extra planet beyond the orb...

  8. Nature of the Kirkwood gaps in the asteroid belt

    Energy Technology Data Exchange (ETDEWEB)

    Dermott, S.F.; Murray, C.D. (Cornell Univ., Ithaca, NY (USA). Lab. for Planetary Studies)

    1983-01-20

    The distributions of orbital eccentricities and inclinations near the Jovian resonances in the asteroid belt show that the observed Kirkwood gaps in the distribution of the semimajor axes were formed after the asteroids had dispersed from the near-coplanar disk in which they accreted.

  9. Uranium deposits of the Grants, New Mexico mineral belt (II)

    International Nuclear Information System (INIS)

    This is part of a study of the genesis of the U deposits of the Grants mineral belt. Enrichment of Mg in ore zones is frequently observed, with chlorite being a common product. Clay mineralogic studies argue for chlorite-illite-montmorillonite associations with ores. The methods include scanning electron microscopy, Eh-pH diagrams, activation analysis, and rare earth element studies

  10. Resolving the planetesimal belt of HR 8799 with ALMA

    Science.gov (United States)

    Booth, Mark; Jordán, Andrés; Casassus, Simon; Hales, Antonio S.; Dent, William R. F.; Faramaz, Virginie; Matrà, Luca; Barkats, Denis; Brahm, Rafael; Cuadra, Jorge

    2016-07-01

    The star HR 8799 hosts one of the largest known debris discs and at least four giant planets. Previous observations have found evidence for a warm belt within the orbits of the planets, a cold planetesimal belt beyond their orbits and a halo of small grains. With the infrared data, it is hard to distinguish the planetesimal belt emission from that of the grains in the halo. With this in mind, the system has been observed with ALMA in band 6 (1.34 mm) using a compact array format. These observations allow the inner edge of the planetesimal belt to be resolved for the first time. A radial distribution of dust grains is fitted to the data using an MCMC method. The disc is best fitted by a broad ring between 145^{+12}_{-12} au and 429^{+37}_{-32} au at an inclination of 40^{+5}_{-6}° and a position angle of 51^{+8}_{-8}°. A disc edge at ˜145 au is too far out to be explained simply by interactions with planet b, requiring either a more complicated dynamical history or an extra planet beyond the orbit of planet b.

  11. Collisional and dynamic evolution of dust from the asteroid belt

    Science.gov (United States)

    Gustafson, Bo A. S.; Gruen, Eberhard; Dermott, Stanley F.; Durda, Daniel D.

    1992-01-01

    The size and spatial distribution of collisional debris from main belt asteroids is modeled over a 10 million year period. The model dust and meteoroid particles spiral toward the Sun under the action of Poynting-Robertson drag and grind down as they collide with a static background of field particles.

  12. Influence of the Gould Belt on Interstellar Extinction

    CERN Document Server

    Gontcharov, George

    2016-01-01

    A new analytical 3D model of interstellar extinction within 500 pc of the Sun as a function of the Galactic spherical coordinates is suggested. This model is physically more justified than the widely used Arenou model, since it takes into account the presence of absorbing matter both in the layer along the equatorial Galactic plane and in the Gould Belt. The extinction in the equatorial layer varies as the sine of the Galactic longitude and in the Gould Belt as the sine of twice the longitude in the Belt plane. The extinction across the layers varies according to a barometric law. It has been found that the absorbing layers intersect at an angle of 17 deg and that the Sun is located near the axial plane of the absorbing layer of the Gould Belt and is probably several parsecs below the axial plane of the equatorial absorbing layer but above the Galactic plane. The model has been tested using the extinction of real stars from three catalogs.

  13. Structural appraisal of the Gadag schist belt from gravity investigations

    Indian Academy of Sciences (India)

    G Ramadass; D Himabindu; N Srinivasulu

    2003-12-01

    Semi-detailed gravity investigations were carried out over an area of approximately 2750 sq km with maximum N-S and E-W extents of 55 and 50km respectively in the Gadag region in the Dharwar craton with a view to obtain a clearer perception of the structural configuration of the region. From qualitative analysis of the gravity data, several tectonic features are inferred: the high density Gadag schist belt is characterized by a gravity high and occurs in two discontinuous segments — the main N-S trending segment, and its thinner NW-SE trending extension, the two separated by a NE-SW trending deep seated fault. While the N-S trend of the Gadag schist belt is bounded on its east by the NW-SE trending Chitradurga thrust fault and on its west by another major NNW-SSE trending fault, the NW-SE extension is likewise bounded by two other NW-SE major faults. Quantitative evaluation from forward modeling/inversion of five profiles in the region, assuming a density contrast of 0.29 gm/cc of the anomalous schistose body with the gneissic host rocks indicated a synclinal structure plunging to the southeast along its axis for the Gadag schist belt. The maximum width and depth from surface of the schist belt are 22km and 5.6km respectively.

  14. 1991 National campaign to increase safety belt usage.

    NARCIS (Netherlands)

    National Highway Traffic Safety Administration NHTSA

    1992-01-01

    The central theme of this paper is the national campaign of the USA to be conducted in 1991 and 1992, in order to reach the goal of 70 percent safety belt usage by 1992. Among other things, it is shown that visible enforcement of existing laws offers the greatest potential for achieving this goal. F

  15. WISE Albedos for Tens of Thousands of Main Belt Asteroids

    NARCIS (Netherlands)

    Masiero, Joseph R.; Mainzer, A. K.; Bauer, J.; Cutri, R.; Dailey, J.; Delbo, M.; Grav, T.; McMillan, R. S.; Mueller, M.; Walker, R.; Wright, E.; WISE Science Team, [No Value

    2010-01-01

    Using thermal IR data from the Wide-field Infrared Survey Explorer (WISE) mission we have calculated diameters for tens of thousands of previously known Main Belt asteroids. Using archival optical observations we have also determined albedos for each object. We present our results from this investig

  16. Shaping mobile belts by small-scale convection.

    Science.gov (United States)

    Faccenna, Claudio; Becker, Thorsten W

    2010-06-01

    Mobile belts are long-lived deformation zones composed of an ensemble of crustal fragments, distributed over hundreds of kilometres inside continental convergent margins. The Mediterranean represents a remarkable example of this tectonic setting: the region hosts a diffuse boundary between the Nubia and Eurasia plates comprised of a mosaic of microplates that move and deform independently from the overall plate convergence. Surface expressions of Mediterranean tectonics include deep, subsiding backarc basins, intraplate plateaux and uplifting orogenic belts. Although the kinematics of the area are now fairly well defined, the dynamical origins of many of these active features are controversial and usually attributed to crustal and lithospheric interactions. However, the effects of mantle convection, well established for continental interiors, should be particularly relevant in a mobile belt, and modelling may constrain important parameters such as slab coherence and lithospheric strength. Here we compute global mantle flow on the basis of recent, high-resolution seismic tomography to investigate the role of buoyancy-driven and plate-motion-induced mantle circulation for the Mediterranean. We show that mantle flow provides an explanation for much of the observed dynamic topography and microplate motion in the region. More generally, vigorous small-scale convection in the uppermost mantle may also underpin other complex mobile belts such as the North American Cordillera or the Himalayan-Tibetan collision zone. PMID:20520711

  17. Paired Magmatic-Metallogenic Belts in Myanmar - an Andean Analogue?

    Science.gov (United States)

    Gardiner, Nicholas; Robb, Laurence; Searle, Michael; Morley, Christopher

    2015-04-01

    Myanmar (Burma) is richly endowed in precious and base metals, having one of the most diverse collections of natural resources in SE Asia. Its geological history is dominated by the staged closing of Tethys and the suturing of Gondwana-derived continental fragments onto the South China craton during the Mesozoic-Cenozoic. The country is located at a crucial geologic juncture where the main convergent Tethyan collision zone swings south around the Namche Barwa Eastern Himalayan syntaxis. However, despite recent work, the geological and geodynamic history of Myanmar remains enigmatic. Plate margin processes, magmatism, metasomatism and the genesis of mineral deposits are intricately linked, and there has long been recognized a relationship between the distribution of certain mineral deposit types, and the tectonic settings which favour their genesis. A better knowledge of the regional tectonic evolution of a potential exploration jurisdiction is therefore crucial to understanding its minerals prospectivity. This strong association between tectonics and mineralization can equally be applied in reverse. By mapping out the spatial, and temporal, distribution of presumed co-genetic mineral deposits, coupled with an understanding of their collective metallogenetic origin, a better appreciation of the tectonic evolution of a terrane may be elucidated. Identification and categorization of metallotects within a geodynamically-evolving terrane thus provides a complimentary tool to other methodologies (e.g. geochemical, geochronological, structural, geophysical, stratigraphical), for determining the tectonic history and inferred geodynamic setting of that terrane through time. Myanmar is one such study area where this approach can be undertaken. Here are found two near-parallel magmatic belts, which together contain a significant proportion of that country's mineral wealth of tin, tungsten, copper, gold and silver. Although only a few 100 km's apart, these belts exhibit a

  18. Belt(s) of debris resolved around the Sco-Cen star HIP 67497

    CERN Document Server

    Bonnefoy, M; Ménard, F; Vigan, A; Lagrange, A -M; Delorme, P; Boccaletti, A; Lazzoni, C; Galicher, R; Desidera, S; Chauvin, G; Augereau, J C; Mouillet, D; Pinte, C; van der Plas, G; Gratton, R; Beust, H; Beuzit, J L

    2016-01-01

    In 2015, we initiated a survey of Scorpius-Centaurus A-F stars that are predicted to host warm-inner and cold-outer belts of debris similar to the case of the system HR~8799. The survey aims to resolve the disks and detect planets responsible for the disk morphology. In this paper, we study the F-type star HIP~67497 and present a first-order modelisation of the disk in order to derive its main properties. We used the near-infrared integral field spectrograph (IFS) and dual-band imager IRDIS of VLT/SPHERE to obtain angular-differential imaging observations of the circumstellar environnement of HIP~67497. We removed the stellar halo with PCA and TLOCI algorithms. We modeled the disk emission with the GRaTeR code. We resolve a ring-like structure that extends up to $\\sim$450 mas ($\\sim$50 au) from the star in the IRDIS and IFS data. It is best reproduced by models of a non-eccentric ring with an inclination of $80\\pm1^{\\circ}$, a position angle of $-93\\pm1^{\\circ}$, and a semi-major axis of $59\\pm3$ au. We also ...

  19. TECTONICS OF THE DABIE OROGENIC BELT, CENTRAL CHINA

    Institute of Scientific and Technical Information of China (English)

    GUO Fu-sheng; XIA Fei; PENG Hua-ming; DU Yang-song

    2002-01-01

    Tectonically the Dabie orogenic belt consists mainly of the Dabieshan Yanshanian uplifted zone and the Beihuaiyang Variscan-Indosinian folding zone. In the north boundary adjoining the North China Block, there are an Early Palaeozoic ophiolitic mixtite belt and the Hefei Mesozoic-Cenozoic faulted basin which overlaps on the suture belt. In the south of Dabie orogen, there is a secondary tectonic unit called Foreland thrust-faulted structural zone which was mainly formed by the intracontinental subductions during Mesozoic era. The study shows that the Dabie Block is a part of mid-late Proterozoic palaeo-island arc at the north margin of Yangtze Block. During Caledonian period, as a submerged uplift at the northen continental margin of Yangtze Block, the Dabie Block collided with the early Palaeozoic palaeo-island arc at the south margin of North China Block, resulting in the convergence of the North and South China Blocks and the disappearance of oceanic crust. Since then,large-scale intracontinental subductions were followed. Dabie Orogenic Belt is the product of overlapping of Yangtze Block, Dabie Block and North China Block under the mechanism of intracontinental subduction. Indosinian period is the period of chief deformation and high pressure dynamic metamorphism for Dabie Block, and Yanshan period is the main orogenic period in which the remelting of crust caused by basement shearing resulted in large scale thermometamorphism. The present tectonic framework of the orogen was finally formed by the rapid uplifting of the Dabieshan mountains and gliding southwards, which result in the developing of thrust belt on south side and the extensional tectonic movement on north side.

  20. Flexible electrode belt for EIT using nanofiber web dry electrodes

    International Nuclear Information System (INIS)

    Efficient connection of multiple electrodes to the body for impedance measurement and voltage monitoring applications is of critical importance to measurement quality and practicality. Electrical impedance tomography (EIT) experiments have generally required a cumbersome procedure to attach the multiple electrodes needed in EIT. Once placed, these electrodes must then maintain good contact with the skin during measurements that may last several hours. There is usually also the need to manage the wires that run between the electrodes and the EIT system. These problems become more severe as the number of electrodes increases, and may limit the practicality and portability of this imaging method. There have been several trials describing human–electrode interfaces using configurations such as electrode belts, helmets or rings. In this paper, we describe an electrode belt we developed for long-term EIT monitoring of human lung ventilation. The belt included 16 embossed electrodes that were designed to make good contact with the skin. The electrodes were fabricated using an Ag-plated PVDF nanofiber web and metallic threads. A large contact area and padding were used behind each electrode to improve subject comfort and reduce contact impedances. The electrodes were incorporated, equally spaced, into an elasticated fabric belt. We tested the electrode belt in conjunction with the KHU Mark1 multi-frequency EIT system, and demonstrate time-difference images of phantoms and human subjects during normal breathing and running. We found that the Ag-plated PVDF nanofiber web electrodes were suitable for long-term measurement because of their flexibility and durability. Moreover, the contact impedance and stability of the Ag-plated PVDF nanofiber web electrodes were found to be comparable to similarly tested Ag/AgCl electrodes. (paper)

  1. ASSESSMENT OF HOMEOWNERSHIP AND ASSET POVERTY IN THE ALABAMA BLACK BELT AND NON-BLACK BELT COUNTIES

    OpenAIRE

    Kanyi, Peter M.; Baharanyi, Ntam; Ngandu, Mudiayi Sylvain; Zabawa, Robert

    2008-01-01

    This study assessed homeownership and how it is affected by race, residency in or out of Alabama Black Belt, family status, poverty and other variables. All variables showed significant relationship to Alabama homeownership with single-parenthood showing a negative impact on White homeownership but insignificant to Black homeownership in the region.

  2. Conveyor Lines - USACE IENC

    Data.gov (United States)

    Department of Homeland Security — These inland electronic Navigational charts (IENCs) were developed from available data used in maintenance of Navigation channels. Users of these IENCs should be...

  3. Driven roller conveyor

    OpenAIRE

    Pokorný, Pavel

    2016-01-01

    Tato bakalářská práce se zabývá výpočetním a konstrukčním návrhem poháněné horizontální válečkové dráhy o délce 100 metrů, pro přepravu plastového materiálu na plastových europaletách nebo v plastových paletových boxech, o maximální hmotnosti břemene 200 kilogramů, v rámci vnitropodnikové přepravy. Součástí této práce je funkční výpočet válečkové dráhy, určení hlavních rozměrů dráhy, pevnostní výpočty pláště a hřídele poháněného válečku a provedení návrhu a kontroly rámu dráhy. V přílohách je...

  4. Nanoscale mass conveyors

    Science.gov (United States)

    Regan, Brian C.; Aloni, Shaul; Zettl, Alexander K.

    2008-03-11

    A mass transport method and device for individually delivering chargeable atoms or molecules from source particles is disclosed. It comprises a channel; at least one source particle of chargeable material fixed to the surface of the channel at a position along its length; a means of heating the channel; and a means for applying an controllable electric field along the channel, whereby the device transports the atoms or molecules along the channel in response to applied electric field. In a preferred embodiment, the mass transport device will comprise a multiwalled carbon nanotube (MWNT), although other one dimensional structures may also be used. The MWNT or other structure acts as a channel for individual or small collections of atoms due to the atomic smoothness of the material. Also preferred is a source particle of a metal such as indium. The particles move by dissociation into small units, in some cases, individual atoms. The particles are preferably less than 100 nm in size.

  5. Break the Green Belt? The differences between green belt and its alternative green wedge : A comparative study of London and Stockholm

    OpenAIRE

    Kong, Luyao

    2012-01-01

    The paper sets out to compare two widely applied planning strategies--- green belt and green wedge--- to understand if as an alternative, the green wedge has more strengths than green belt. Green belt has long been the planning policy with a steady position in UK, and also accepted by other countries, Australia, Japan, Korea for example. But during recent years, this policy has been under accusation for fostering un-sustainability, housing shortage and value degradation of the green space. A ...

  6. 螺旋叶片对垂直螺旋输送机性能的影响%Influence of screw blade of performance for vertical screw conveyor

    Institute of Scientific and Technical Information of China (English)

    余书豪; 谌永祥

    2016-01-01

    为了研究在垂直螺旋输送机物料输送过程中的细观甚至微观特征,降低颗粒输送过程中近轴处的涡流引起的能耗,增大近壁面处的轴向速度,考察不同母线形状的螺旋叶片,借助颗粒仿真软件EDEM 2.5进行数值试验,模拟垂直螺旋输送机内颗粒速度、功率消耗、能量耗散、质量流量等性能指标,通过数据处理软件Origin Pro 8.0作图分析各项指标的变化情况.结果表明:与传统直线型母线的螺旋叶片相比,弯曲型母线的螺旋叶片在近轴处的切向速度减小73.87%,大大降低近轴处的涡流效应;近壁面处的轴向速度在高转速时增大12.34%,完成预定输送任务基础上,有效地降低额外的能量消耗,提升整机性能.%In order to figure out the meso and microscopic characteristics during bulk material being conveyed within the vertical screw conveyor and reduce the swirl flow near the screw shag and increase the axial velocity of particles near the wall during the particulate being conveyed,the different shape screw blades were surveyed,by means of the software of particle simulation EDEM 2.5,numerical test was done,the standards of performance such as particle velocity,power consumption,energy dissipation and average mass flow rate within the vertical screw conveyor were simulated.The trend charts were plotted based on the data processing software Origin Pro 8.0,to analysis the changes of indicators.The result shows that compared with the line type screw blade,the curved screw blade of tangential velocity near the shaft is reduce by 73.87%,the vortex motion decreases evidently.The axial velocity near the wall is increased by 12.34%,the extra energy dissipation effectively reduces on the basis of finishing the intended work,which promotes the whole performance of vertical screw conveyor

  7. Dynamics of the earth's radiation belts and inner magnetosphere (geophysical monograph series)

    CERN Document Server

    2013-01-01

    Dynamics of the Earth's Radiation Belts and Inner Magnetosphere draws together current knowledge of the radiation belts prior to the launch of Radiation Belt Storm Probes (RPSP) and other imminent space missions, making this volume timely and unique. The volume will serve as a useful benchmark at this exciting and pivotal period in radiation belt research in advance of the new discoveries that the RPSP mission will surely bring. Highlights include the following: a review of the current state of the art of radiation belt science; a complete and up-to-date account of the wave-particle interactions that control the dynamical acceleration and loss processes of particles in the Earth's radiation belts and inner magnetosphere; a discussion emphasizing the importance of the cross-energy coupling of the particle populations of the radiation belts, ring current, and plasmasphere in controlling the dynamics of the inner magnetosphe...

  8. Toroidal, Counter-Toroidal, and Upwelling Flow in the Mantle Wedge of the Rivera and Cocos Plates: Implications for IOB Geochemistry in the Trans-Mexican Volcanic Belt

    Science.gov (United States)

    Neumann, Florian; Vásquez-Serrano, Alberto; Tolson, Gustavo; Negrete-Aranda, Raquel; Contreras, Juan

    2016-10-01

    We carried out analog laboratory modeling at a scale 1:4,000,000 and computer rendering of the flow patterns in a simulated western Middle American subduction zone. The scaled model consists of a transparent tank filled with corn syrup and housing two conveyor belts made of polyethylene strips. One of the strips dips 60° and moves at a velocity of 30 mm/min simulating the Rivera plate. The other one dips 45°, moves at 90 mm/min simulating the subduction of the Cocos plate. Our scaled subduction zone also includes a gap between the simulated slabs analogous to a tear recently observed in shear wave tomography studies. An acrylic plate 3 mm thick floats on the syrup in grazing contact with the polyethylene strips and simulates the overriding North America plate. Our experiments reveal a deep toroidal flow of asthenospheric mantle through the Cocos-Rivera separation. The flow is driven by a pressure gradient associated with the down-dip differential-motion of the slabs. Similarly, low pressure generated by the fast-moving Cocos plate creates a shallow counter-toroidal flow in the uppermost 100 km of the mantle wedge. The flow draws mantle beneath the western Trans-Mexican Volcanic Belt to the Jalisco block, then plunges into the deep mantle by the descending poloidal cell of the Cocos slab. Moreover, our model suggests a hydraulic jump causes an ~250 km asthenosphere upwelling around the area where intra-arc extensional systems converge in western Mexico. The upwelling eventually merges with the shallow counter-toroidal flow describing a motion in 3D space similar to an Archimedes' screw. Our results indicate the differential motion between subducting slabs drives mixing in the mantle wedge of the Rivera plate and allows the slab to steepen and retreat. Model results are in good agreement with seismic anisotropy studies and the geochemistry of lavas erupted in the Jalisco block. The model can explain the eruption of OIB lavas in the vicinity of the City of

  9. Toroidal, Counter-Toroidal, and Upwelling Flow in the Mantle Wedge of the Rivera and Cocos Plates: Implications for IOB Geochemistry in the Trans-Mexican Volcanic Belt

    Science.gov (United States)

    Neumann, Florian; Vásquez-Serrano, Alberto; Tolson, Gustavo; Negrete-Aranda, Raquel; Contreras, Juan

    2015-12-01

    We carried out analog laboratory modeling at a scale 1:4,000,000 and computer rendering of the flow patterns in a simulated western Middle American subduction zone. The scaled model consists of a transparent tank filled with corn syrup and housing two conveyor belts made of polyethylene strips. One of the strips dips 60° and moves at a velocity of 30 mm/min simulating the Rivera plate. The other one dips 45°, moves at 90 mm/min simulating the subduction of the Cocos plate. Our scaled subduction zone also includes a gap between the simulated slabs analogous to a tear recently observed in shear wave tomography studies. An acrylic plate 3 mm thick floats on the syrup in grazing contact with the polyethylene strips and simulates the overriding North America plate. Our experiments reveal a deep toroidal flow of asthenospheric mantle through the Cocos-Rivera separation. The flow is driven by a pressure gradient associated with the down-dip differential-motion of the slabs. Similarly, low pressure generated by the fast-moving Cocos plate creates a shallow counter-toroidal flow in the uppermost 100 km of the mantle wedge. The flow draws mantle beneath the western Trans-Mexican Volcanic Belt to the Jalisco block, then plunges into the deep mantle by the descending poloidal cell of the Cocos slab. Moreover, our model suggests a hydraulic jump causes an ~250 km asthenosphere upwelling around the area where intra-arc extensional systems converge in western Mexico. The upwelling eventually merges with the shallow counter-toroidal flow describing a motion in 3D space similar to an Archimedes' screw. Our results indicate the differential motion between subducting slabs drives mixing in the mantle wedge of the Rivera plate and allows the slab to steepen and retreat. Model results are in good agreement with seismic anisotropy studies and the geochemistry of lavas erupted in the Jalisco block. The model can explain the eruption of OIB lavas in the vicinity of the City of

  10. 冰晶石湿料螺旋输送机的故障分析%Fault analysis of screw conveyor for transporting wet material of cryolite

    Institute of Scientific and Technical Information of China (English)

    业文成

    2012-01-01

    LS型螺旋输送机输送冰晶石湿料常发生螺旋轴扭断故障,分析故障产生的原因,介绍为防止螺旋输送机故障在管理、物料及设备方面所采取的整改措施,达到了设备稳定运行的效果。%The LS type screw conveyor for transporting wet material of cryolite screw shaft, the reasons of the fault are analyzed, the rectification measures in usually happen twist off of management, materials and equipment of the action for preventing fault are introduced, achieving the stable operation of the equipment.

  11. 螺旋输送机在固废处理中的应用与展望%Application and Prospect of Screw Conveyor in Solid Waste Disposal

    Institute of Scientific and Technical Information of China (English)

    柴彬; 闫志海; 魏少华; 葛砚; 唐滨

    2016-01-01

    螺旋输送机具有结构简单、横截面积小、密封性好、操作方便、维修容易、便于封闭运输等优点。简要介绍了螺旋输送机的结构组成和工作原理及其在飞灰处理、除臭卸料、垃圾渗沥液等固废处理方面的应用。%The screw conveyor has advantages of simple structure,small cross-sectional area,good sealing,convenient operation,easy to maintain and enclosed conveying,etc.This article briefly introduces its structure,working principle and application in solid waste disposal such as fly ash handling,deodorant discharge and leachate treatment.

  12. Tribological Properties of Metal V-Belt Type CVT Lubricant

    Directory of Open Access Journals (Sweden)

    Keiichi Narita

    2012-01-01

    Full Text Available The priority for lubricant performance for metal V-belt-type CVT (B-CVTFs should be the improvement of transmittable torque capacity between the belt and pulley plus excellent antishudder properties for lockup clutch used in B-CVTs. This study intends to investigate the effect of lubricant additives for improving these performances of B-CVTs. In addition, surface analysis techniques were utilized to gain a novel insight into the chemical composites and morphology of the tribofilms. As a result, it is vital for greater torque capacity to give higher boundary friction coefficient between the metal contacting interfaces, and the process of boundary lubricant film formation derived from antiwear additives used in B-CVTFs strongly impacts on the torque capacity. Moreover, it is found that a sort of lubricant formulation gave an excellent antishudder performance for wet clutch with keeping higher friction coefficient between the metals, which would result in improving the performance of B-CVTs.

  13. MINIMIZATION OF CORD WASTAGES IN BELT INDUSTRY USING DMAIC

    Directory of Open Access Journals (Sweden)

    SHAILESH N. KHEKALE,

    2010-08-01

    Full Text Available Manufacturing processes tend to produce operational wastages due to various reasons, which can be reduced by identifying and eliminating those using Six Sigma methodologies. In the presented work, DMAIC (Define, Measure, Analyze, Improve and Control has been used to reduce cord wastages in belt manufacturing. Core issues, pain areas or processes related to cord wastages are identified to formulate the problem. Later the concerned data is collected to examine the current performance and process capability; also the root causes are identified. Solutions are found out from improvement point of view, and various tools are properly implemented for tracking the processes. This study reports reduction in cord wastages in belt manufacturing through reduction in DPMO (Defects per Million Opportunities from 549531 to 17240, also the Sigma Level isimproved from 1.37 to 3.6.

  14. Statistical properties of the radiation belt seed population

    Science.gov (United States)

    Boyd, A. J.; Spence, H. E.; Huang, C.-L.; Reeves, G. D.; Baker, D. N.; Turner, D. L.; Claudepierre, S. G.; Fennell, J. F.; Blake, J. B.; Shprits, Y. Y.

    2016-08-01

    We present a statistical analysis of phase space density data from the first 26 months of the Van Allen Probes mission. In particular, we investigate the relationship between the tens and hundreds of keV seed electrons and >1 MeV core radiation belt electron population. Using a cross-correlation analysis, we find that the seed and core populations are well correlated with a coefficient of ≈0.73 with a time lag of 10-15 h. We present evidence of a seed population threshold that is necessary for subsequent acceleration. The depth of penetration of the seed population determines the inner boundary of the acceleration process. However, we show that an enhanced seed population alone is not enough to produce acceleration in the higher energies, implying that the seed population of hundreds of keV electrons is only one of several conditions required for MeV electron radiation belt acceleration.

  15. The Analysis of Insects Population on Fields in Forest Belts

    OpenAIRE

    Gribust Irina Romuvaldovna

    2014-01-01

    The introduction into the agricultural and ecological system of multifunctional forest belts contributes to the formation of a qualitatively new environment, and, as a consequence, to the transformation of insects populations. Change of the faunal diversity in transformed agro-ecosystems and identification of entomofauna characteristics by a number of biotic indices, which undergo cumulative impact of organized farm ecosystem components, have not been sufficiently studied. This question is th...

  16. Discovery of the candidate Kuiper belt object 1992 QB1

    Science.gov (United States)

    Jewitt, David; Luu, Jane

    1993-01-01

    The discovery of a new faint object in the outer solar system, 1992 QB1, moving beyond the orbit of Neptune is reported. It is suggested that the 1992 QB1 may represent the first detection of a member of the Kuiper belt (Edgworth, 1949; Kuiper, 1951), the hypothesized population of objects beyond Neptune and a possible source of the short-period comets, as suggested by Whipple (1964), Fernandez (1980), and Duncan et al. (1988).

  17. Radiation Belt Electron Dynamics Driven by Large-Amplitude Whistlers

    Science.gov (United States)

    Khazanov, G. V.; Tel'nikhin, A. A.; Kronberg, T. K.

    2013-01-01

    Acceleration of radiation belt electrons driven by oblique large-amplitude whistler waves is studied. We show analytically and numerically that this is a stochastic process; the intensity of which depends on the wave power modified by Bessel functions. The type of this dependence is determined by the character of the nonlinear interaction due to coupling between action and phase. The results show that physically significant quantities have a relatively weak dependence on the wave power.

  18. Future aerosol reductions and widening of the northern tropical belt

    Science.gov (United States)

    Allen, Robert J.; Ajoku, Osinachi

    2016-06-01

    Observations show that the tropical belt has widened over the past few decades, a phenomenon associated with poleward migration of subtropical dry zones and large-scale atmospheric circulation. Although part of this signal is related to natural climate variability, studies have identified an externally forced contribution primarily associated with greenhouse gases (GHGs) and stratospheric ozone loss. Here we show that the increase in aerosols over the twentieth century has led to contraction of the northern tropical belt, thereby offsetting part of the widening associated with the increase in GHGs. Over the 21st century, however, when aerosol emissions are projected to decrease, the effects of aerosols and GHGs reinforce one another, both contributing to widening of the northern tropical belt. Models that have larger aerosol forcing, by including aerosol indirect effects on cloud albedo and lifetime, yield significantly larger Northern Hemisphere (NH) tropical widening than models with direct aerosol effects only. More targeted simulations show that future reductions in aerosols can drive NH tropical widening as large as greenhouse gases, and idealized simulations show the importance of NH midlatitude aerosol forcing. Mechanistically, the 21st century reduction in aerosols peaks near 40°N, which results in a corresponding maximum increase in surface solar radiation, NH midlatitude tropospheric warming amplification, and a poleward shift in the latitude of maximum baroclinicity, implying a corresponding shift in atmospheric circulation. If models with aerosol indirect effects better represent the real world, then future aerosol changes are likely to be an important -- if not dominant -- driver of NH tropical belt widening.

  19. Development of a new Global RAdiation Belt model: GRAB

    Science.gov (United States)

    Sicard-Piet, Angelica; Lazaro, Didier; Maget, Vincent; Rolland, Guy; Ecoffet, Robert; Bourdarie, Sébastien; Boscher, Daniel; Standarovski, Denis

    2016-07-01

    The well known AP8 and AE8 NASA models are commonly used in the industry to specify the radiation belt environment. Unfortunately, there are some limitations in the use of these models, first due to the covered energy range, but also because in some regions of space, there are discrepancies between the predicted average values and the measurements. Therefore, our aim is to develop a radiation belt model, covering a large region of space and energy, from LEO altitudes to GEO and above, and from plasma to relativistic particles. The aim for the first version is to correct the AP8 and AE8 models where they are deficient or not defined. At geostationary, we developed ten years ago for electrons the IGE-2006 model which was proven to be more accurate than AE8, and used commonly in the industry, covering a broad energy range, from 1keV to 5MeV. From then, a proton model for geostationary orbit was also developed for material applications, followed by the OZONE model covering a narrower energy range but the whole outer electron belt, a SLOT model to asses average electron values for 2file system to switch between models, in order to obtain at each location in space and energy point the most reliable value. Of course, the way the model is developed is well suited to add new local developments or to include international partnership. This model will be called the GRAB model, as Global Radiation Belt model. We will present first beta version during this conference.

  20. The benefit of seat belt legislation in the United Kingdom.

    OpenAIRE

    M. McCarthy

    1989-01-01

    Legislation for compulsory wearing of seat belts by car drivers and front seat passengers has been acclaimed as a major public health advance. Reports from other countries, and two recent evaluative studies in the United Kingdom, have suggested that legislation reduces both deaths and injuries. To assess the effect of the UK law 5 years after its implementation, trends in routine data for 1976-1987 have been reviewed. There were two sources of data: mortality statistics, published by the Offi...

  1. Coralling a distant planet with extreme resonant Kuiper belt objects

    CERN Document Server

    Malhotra, Renu; Wang, Xianyu

    2016-01-01

    The four longest period Kuiper belt objects have orbital periods close to small integer ratios with each other. A hypothetical planet with orbital period $\\sim$17,117 years, semimajor axis $\\sim$665 AU, would have N/1 and N/2 period ratios with these four objects. The orbital geometries and dynamics of resonant orbits constrain the orbital plane, the orbital eccentricity and the mass of such a planet, as well as its current location in its orbital path.

  2. Rotation Period Determination of Four Main-belt Asteroids

    Science.gov (United States)

    Ferrero, Andrea

    2016-10-01

    Observations of four main-belt asteroids (MBA) revealed the following rotation periods and lightcurve amplitudes: 3861 Lorenz, P = 11.91 ± 0.01 h, A = 0.28 mag; 6173 Jimwestphal P = 2.908 ± 0.001 h, A = 0.41 mag; 10259 Osipovyurij, P = 6.356 ± 0.001 h, A = 0.30 mag; 29470 Higgs, P = 36.31 ± 0.01 h, A = 0.48 mag.

  3. Inner radiation belt source of helium and heavy hydrogen isotopes

    Science.gov (United States)

    Leonov, A. A.; Galper, A. M.; Koldashov, S. V.; Mikhailov, V. V.; Casolino, M.; Picozza, P.; Sparvoli, R.

    Nuclear interactions between inner zone protons and atoms in the upper atmosphere provide the main source of energetic H and He isotopes nuclei in the radiation belt. This paper reports on the specified calculations of these isotope intensities using various inner zone proton intensity models (AP-8 and SAMPEX/PET PSB97), the atmosphere drift-averaged composition and density model MSIS-90, and cross-sections of the interaction processes from the GNASH nuclear model code. To calculate drift-averaged densities and energy losses of secondaries, the particles were tracked in the geomagnetic field (modelled through IGRF-95) by integrating numerically the equation of the motion. The calculations take into account the kinematics of nuclear interactions along the whole trajectory of trapped proton. The comparison with new data obtained from the experiments on board RESURS-04 and MITA satellites and with data from SAMPEX and CRRES satellites taken during different phases of solar activity shows that the upper atmosphere is a sufficient source for inner zone helium and heavy hydrogen isotopes. The calculation results are energy spectra and angular distributions of light nuclear isotopes in the inner radiation belt that may be used to develop helium inner radiation belt model and to evaluate their contribution to SEU (single event upset) rates.

  4. Structural setting of the Apennine-Maghrebian thrust belt

    Institute of Scientific and Technical Information of China (English)

    PieroElter; MarioGrasso; MaurizioParotto; LivioVezzani

    2003-01-01

    The Apennine-Maghrebian fold-and-thrust belt devel-oped from the latest Cretaceous to Early Pleistocene at the subduction-collisional boundary between the Euro-pean and the westward-subducted Ionian and Adria plates. Large parts of the Mesozoic oceanic lithosphere were subducted during an Alpine phase from the Late Cretaceous to Middle Eocene. The chain developed through the deformation of major paleogeographic internal domains (tectono-sedimentary sequences of the Ligurian-Piedmont Ocean) and external domains (sedi-mentary sequences derived from the deformation of the continental Adria-African passive mareinL The continu-ity of the Apennine chain is abruptly interrupted in the Calabrian Arc by the extensive klippe of Kabylo-Calabrian crystalline exotic terranes, derived from deformation of the European passive margin.Major complexities (sharp deflections in the arcuate configuration of the thrust belt, out-of-sequence propagation of the thrusts) are referred to contrasting rheology and differential buoyancy of the subducted lithosphere (transitional from conti-nental to oceanic) and consequent differential roll-back of the Adria plate margin, and to competence contrasts in the Mesozoic stratigraphic sequences,where multiple décollement horizons at different stratigraphic levels may have favored significant differential shortening.From the Late Miocene, the geometry of the thrust belt was strongly modified by extensional fault-ing, volcanic activity, crustal thinning and formation of oceanic crust correlated with the development of the Tyrrhenian Basin.

  5. Investigating radiation belt losses though numerical modelling of precipitating fluxes

    Directory of Open Access Journals (Sweden)

    C. J. Rodger

    2004-11-01

    Full Text Available It has been suggested that whistler-induced electron precipitation (WEP may be the most significant inner radiation belt loss process for some electron energy ranges. One area of uncertainty lies in identifying a typical estimate of the precipitating fluxes from the examples given in the literature to date. Here we aim to solve this difficulty through modelling satellite and ground-based observations of onset and decay of the precipitation and its effects in the ionosphere by examining WEP-produced Trimpi perturbations in subionospheric VLF transmissions. In this study we find that typical Trimpi are well described by the effects of WEP spectra derived from the AE-5 inner radiation belt model for typical precipitating energy fluxes. This confirms the validity of the radiation belt lifetimes determined in previous studies using these flux parameters. We find that the large variation in observed Trimpi perturbation size occurring over time scales of minutes to hours is primarily due to differing precipitation flux levels rather than changing WEP spectra. Finally, we show that high-time resolution measurements during the onset of Trimpi perturbations should provide a useful signature for discriminating WEP Trimpi from non-WEP Trimpi, due to the pulsed nature of the WEP arrival.

  6. An Experimental Concept for Probing Nonlinear Radiation Belt Physics

    Science.gov (United States)

    Amatucci, Bill; Ganguli, Guru; Crabtree, Chris; Mithaiwala, Manish; Siefring, Carl; Tejero, Erik

    2014-10-01

    The SMART sounding rocket is designed to probe the nonlinear response of a known ionospheric stimulus. High-speed neutral barium atoms generated by a shaped charge explosion perpendicular to the magnetic field in the ionosphere form a ring velocity distribution of photo-ionized Ba+ that will generate lower hybrid waves. Induced nonlinear scattering of lower hybrid waves into whistler/magnetosonic waves has been theoretically predicted, confirmed by simulations, and observed in the lab. The effects of nonlinear scattering on wave evolution and whistler escape to the radiation belts have been studied and observable signatures quantified. The fraction of the neutral atom kinetic energy converted into waves is estimated at 10-12%. SMART will carry a Ba release module and an instrumented daughter section with vector wave magnetic and electric field sensors, Langmuir probes and energetic particle detectors to determine wave spectra in the source region and detect precipitated particles. The Van Allen Probes can detect the propagation of the scattered whistlers and their effects in the radiation belts. By measuring the radiation belt whistler energy density, SMART will confirm the nonlinear scattering process and the connection to weak turbulence. Supported by the Naval Research Laboratory Base Funds.

  7. Periodicity in tree rings from the corn belt.

    Science.gov (United States)

    Meko, D M; Stockton, C W; Blasing, T J

    1985-07-26

    Previous tree-ring studies indicated that the total area affected by drought in the western United States has rhythmically expanded and contracted over the past 300 years, with a period near the 18.6-year lunar nodal and 22-year double-sunspot cycles. Recently collected tree-ring data from the U.S. Corn Belt for the years 1680 to 1980 were examined for evidence of either of these cycles on a regional scale. Spectral analysis indicated no periodicity in the eastern part of the Corn Belt, but a significant 18.33-year period in the western part. The period length changed from 17.60 to 20.95 years between the first 150 years and the last 151. High-resolution frequency analysis showed that the structure of the 18.33-year spectral peak was complex, with contributions from several frequencies near both the lunar nodal and double-sunspot periods. A t-test of difference of means in reconstructed annual precipitation weakly corroborated a previous finding of an association between drought area and the phase of the double-sunspot cycle. Both the high-resolution frequency analysis and the t-test results indicate that the periodic component of drought near 20 years is too weak and irregular to be of use in drought forecasting for the Corn Belt.

  8. Detection of Small Kuiper Belt Objects by Stellar Occultations

    CERN Document Server

    Stevenson, R

    2007-01-01

    Knowledge of the Kuiper Belt is currently limited to those objects that can be detected directly. Objects with diameters less than $\\sim$10km reflect too little light to be detected. These smaller bodies could contain most of the mass in the Kuiper Belt while the abundance of these bodies may constrain the distribution of mass. The overall size distribution of bodies within the Kuiper Belt can also be inferred from the relative abundances of sub-km and larger bodies. Stellar occultations are already used to study dark objects in the Solar System, such as asteroids or planetary rings. Occultation by a KBO of a size comparable to, or larger than, that of the Fresnel Scale will result in Fresnel diffraction. Detection of diffraction effects requires fast multiple-star photometry, which will be conducted in July 2007 using the Orthogonal Parallel Transfer Imaging Camera (OPTIC) mounted on the University of Hawaii 2.2m telescope on Mauna Kea. This paper details how knowledge of the mass and structure of the outer ...

  9. Non-Vestoid candidates in the inner Main Belt

    Science.gov (United States)

    Moskovitz, Nicholas; Oszkiewicz, Dagmara; Skiff, Brian; Kankiewicz, Pawel; Licandro, Javier; Galiazzo, Mattia; Zeilinger, Werner

    2016-10-01

    Most Howardite-Eucrite-Diogenite (HED) meteorites (analogues to V-type asteroids) are thought to originate from asteroid (4) Vesta. However some HEDs show distinct oxygen isotope ratios and therefore are thought to originate from other asteroids. In this study we try to identify asteroids that may represent parent bodies of those mismatching HEDs. In particular the origin of the anomalous Bunburra Rockhole meteorite was traced back to the inner main asteroid belt, showing that there might be asteroids that are not genetically linked to the asteroid (4) Vesta (the main source of V-type asteroids and HED meteorites) in the inner main belt. In this work we identify V-type asteroids outside the dynamical Vesta family whose rotational properties (retrograde vs prograde rotation) suggest the direction of Yarkovsky drift that sets them apart from typical Vestoids and Vesta fugitives. Specificly Nesvorny et al. 2008 simulated escapes paths from the Vesta family and showed that typical Vesta fugitives in the inner main asteroid belt at semi-major axis a drift or showing Yarkovsky drift direction towards (4) Vesta are the best candidates for non-Vestoidal V-type asteroids and therefore parent bodies of anomalous HED. In this study we have performed accurate photometric observations and determined sense of rotation for several asteroids testing their links to Vesta and anomalous HED. We have found several potential non-Vestoid candidates. Those objects have to be studied in more detail to fully confirm their link to anomalous HEDs.

  10. Collisional Grooming Models of the Kuiper Belt Dust Cloud

    CERN Document Server

    Kuchner, Marc J

    2010-01-01

    We modeled the 3-D structure of the Kuiper Belt dust cloud at four different dust production rates, incorporating both planet-dust interactions and grain-grain collisions using the collisional grooming algorithm. Simulated images of a model with a face-on optical depth of ~10^-4 primarily show an azimuthally-symmetric ring at 40-47 AU in submillimeter and infrared wavelengths; this ring is associated with the cold classical Kuiper Belt. For models with lower optical depths (10^-6 and 10^-7), synthetic infrared images show that the ring widens and a gap opens in the ring at the location of of Neptune; this feature is caused by trapping of dust grains in Neptune's mean motion resonances. At low optical depths, a secondary ring also appears associated with the hole cleared in the center of the disk by Saturn. Our simulations, which incorporate 25 different grain sizes, illustrate that grain-grain collisions are important in sculpting today's Kuiper Belt dust, and probably other aspects of the Solar System dust c...

  11. Tool Belts: Latitudinal-Belt Predictions for the Persistence of Landscapes

    Science.gov (United States)

    Willenbring, Jane; Brocard, Gilles

    2016-04-01

    The ability of rivers to cut through rock and re-establish equilibrium sets the pace of landscape response to uplift. Because of associations between tectonics, erosion, and weathering, high rates of rock uplift may initiate a cascade of processes that are linked to high rates of weathering and eventually sequestration of CO2 over geologic timescales. How long does it take to completely change the topographic form after uplift and where on Earth do relict landscapes persist despite uplift? Large expanses of subdued landscapes are common at high elevation in mountain ranges. Preservation of subdued fragments amongst steeply dissected regions can therefore be a simple matter of chance, reflecting the time it takes for dissection to remove any remaining parcel of the pre-existing topography after a tectonic perturbation. Some of these relicts may, however, possess characteristics - often a product of the climate - that make them intrinsically resistant to dissection. One common mode of conversion of a subdued landscape into a deeply dissected one is the propagation of upstream-migrating erosion waves that transmit the signal of uplift and base level lowering across entire landscapes. Following a shift in tectonic forcing, the Earth's surface progressively adjusts its topographic form over millions of years, seeking to re-establish equilibrium with the new forcing. Here, we show that a high degree of weathering leading to smaller average soil grains at the surface hinders the capacity of rivers to incise. We show that globally, rates of cosmogenic nuclide-derived denudation rates fall into latitudinal belts with (1) low rates of denudation in areas with high temperatures and high precipitation where rock fragments do not persist at the soil surface, (2) high rates of denudation at mid-latitudes where rock fragments exist and are carried efficiently by the river flow, and (3) low rates of denudation at high latitudes where large grains at the surface inhibit channelized

  12. Structure of the Asteroid Belt from the Gas Giants' Growth and Chaotic Dynamics

    Science.gov (United States)

    Izidoro, André; Raymond, Sean N.; Pierens, Arnaud; Morbidelli, Alessandro; Winter, Othon; Nesvorny, David

    2016-05-01

    The structure of the asteroid belt holds a record of the Solar System's dynamical history. The current belt only contains 10-3 Earth masses yet the asteroids' orbits are dynamically excited, with a large spread in eccentricity and inclination. The belt is also chemically segregated: the inner belt is dominated by dry S-types and the outer belt by hydrated C-types. Here we propose a new model in which the asteroid belt was always low-mass and was partially populated and sculpted by the giant planets on chaotic, resonant orbits. We first show that the compositional dichotomy of the asteroid belt is a simple consequence of Jupiter's growth in the gaseous protoplanetary disk. As Jupiter's core rapidly grew by accreting gas, orbits of nearby planetesimals were perturbed onto Jupiter-crossing trajectories. A significant fraction (~10%) of objects in the neighborhood exterior of Jupiter's orbit were implanted by gas drag into the outer parts of the asteroid belt as C-types. While the gas giants were likely in mean motion resonance at the end of the gaseous disk phase, we show that small perturbations may have driven them into a chaotic but stable state. After the dissipation of the gaseous disk, stochastic variations in the gas giants orbits caused resonances to chaotically jump across the main belt and excite the asteroids' orbits. Our results suggest that the early Solar System was chaotic and introduce a simple framework to understand the origins of the asteroid belt.

  13. 沥青混合料保温车螺旋输送机结构设计和仿真%Design and Simulation of the Screw Conveyor for Asphalt Mixing Material Insulation Vehicle

    Institute of Scientific and Technical Information of China (English)

    高长银; 虞正平; 吴晓铃

    2013-01-01

    针对沥青混合料保温车螺旋输送机,从速度分析入手,应用数学方法推导出螺旋输送机的轴向运动速度和圆周速度,从而进一步推导出螺旋轴转速、螺旋叶片直径、螺旋螺距等计算公式,进而完成沥青混合料螺旋输送机参数设计.最后,运用工程流体力学软件EFD软件建立了螺旋输送机内物料流动分析模型,对沥青混合料流动过程进行数值模拟,结果表明,输送机工作时将能带动物料混合搅拌,但由于出口处空间限制,要靠螺旋面挤出卸料,应尽可能减少伸出尺寸.%For the screw conveyor of the asphalt mixture insulation vehicle,by means of the mathematical methods the axial movement speed and the circumferential speed of the screw conveyor are derived,and then the calculation formula of the spiral shaft rotation speed,helical blade diameter and pitch are deduced.According to the calculation formula,the design parameters of the screw conveyor of the asphalt mixture insulation vehicle are calculated.Finally,by using of Engineering Fluid Dynamics software the material flow analysis model of the screw conveyor is established,and the flow field of asphalt mixing material is simulated.The results show that the screw conveyor can stir and mix the materials,as a result of exit space limitation the material is dumped by screw extrusion and should minimize the extend size.The reference for the selection,design and optimization of the screw conveyor will be provided by the research results.

  14. The constraints of strain partitioning and geochronology in Luonan-Luanchuan tectonic belts on Qinling orogenic belt

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The Luonan-Luanchuan tectonic belt lies between the North China Block and Qinling Mountains, in- cluding the Luonan-Luanchuan fault zone and the strong deformation zone to the north of the fault. The ductile shear zone, imbricate brittle fault and duplex structure in the fault zone now are the expression of the same tectonic event in different depth. Such lineation structure exists in the tectonic belts as mineral lineation, elongation lineation, crenulation lineation, sheath folds and so on, indicating NE-directed plate motion. Fold axes and thrusts in the strong deformation zone are inclined to the Luonan-Luanchuan fault zone at small angles. The structures with different natures show a regular pattern, produced during oblique convergence of plates. The convergence factors are as follows:The direction of plate convergence is 22°, 31° and the angle between the plate convergence direction and plate boundary is 73°, 82° respectively in the west and east segment. The Luonan-Luanchuan tectonic belt was deformed strongly in 372 Ma, resulted from Erlangping back-arc ocean basin subduction sin- istrally and obliquely to North China Block during the collision of North China Block and South China Block.

  15. The constraints of strain partitioning and geochronology in Luonan-Luanchuan tectonic belts on Qinling orogenic belt

    Institute of Scientific and Technical Information of China (English)

    SONG ChuanZhong; ZHANG GuoWei; WANG YongSheng; LI JiaHao; CHEN ZeChao; CAI ZhiChuan

    2009-01-01

    The Luonan-Luanchuan tectonic belt lies between the North China Block and Qinling Mountains,including the Luonan-Luanchuan fault zone and the strong deformation zone to the north of the fault.The ductile shear zone,imbricate brittle fault and duplex structure in the fault zone now are the expression of the same tectonic event in different depth.Such lineation structure exists in the tectonic belts as mineral lineation,elongation lineation,crenulation lineation,sheath folds and so on,indicating NE-directed plate motion.Fold axes and thrusts in the strong deformation zone are inclined to the Luonan-Luanchuan fault zone at small angles.The structures with different natures show a regular pattern,produced during oblique convergence of plates.The convergence factors are as follows:The direction of plate convergence is 22°,31° and the angle between the plate convergence direction and plate boundary is 73°,82° respectively in the west and east segment.The Luonan-Luanchuan tectonic belt was deformed strongly in 372 Ma,resulted from Erlangping back-arc ocean basin subduction sinistrally and obliquely to North China Block during the collision of North China Block and South China Block.

  16. The prevalence of seat belt use in Jamaica. An observational study.

    Science.gov (United States)

    Crandon, I W; Branday, J M; Simeon, D T; Rhoden, A; Thompson, H; Carpenter, R

    1996-03-01

    An observational cross-sectional survey showed that 21.1% of private motor vehicle drivers and 13.5% of front seat passengers voluntarily wore seat belts in Kingston, Jamaica, where there is no law requiring this. Rear passenger utilisation was not examined. Compared to males, females were significantly more likely to wear seat belts when driving but not as front seat passengers. Of all motor vehicles examined, 10.1% were not equipped with seat belts. The oldest group of vehicles were mostly not fitted with seat belts. Drivers of older vehicles were significantly less likely to use seat belts even when the vehicles were equipped with belts. Implementation of legislation can reduce mortality, morbidity and costs from road traffic accidents which are relatively frequent in Jamaica. Male drivers, drivers of older vehicles and all passengers may require specific targeting in an educational and enforcement campaign should legislation, which is highly desirable, be implemented.

  17. 高温水冷倾斜25°螺旋输送机的设计与应用%Design and Application of Water-cooled Screw Conveyor Inclined at 25°

    Institute of Scientific and Technical Information of China (English)

    王一冰; 杨志勇

    2015-01-01

    针对3 M W循环流化床锅炉岛系统热态试验台工程设计了高温水冷倾斜25°螺旋输送机。介绍了高温水冷倾斜25°螺旋输送机的主要参数、输送工艺和结构特点。%Aiming at the thermalstate test rig for boiler island system of 3 MW circulating fluidized bed ,we design a 25° inclined screw conveyor cooled by water .This paper introduces the main parameters ,process and structure features of the water‐cooled screw conveyor inclined at 25° .

  18. Analysis on Earth Conveying and Pressure Maintaining of Screw Conveyors of EPB Shields%土压平衡盾构螺旋输送机排土及保压作用分析

    Institute of Scientific and Technical Information of China (English)

    周冠南

    2012-01-01

    The earth conveying and pressure maintaining of screw conveyors play an important role in the safe and effi- cient boring of EPB shields. The working principles and influencing factors of the earth conveying and pressure maintai- ning of screw conveyors are systematically analyzed. Conclusions drawn are as follows : 1 ) The earth pressure balance in the boring of EPB shields includes the pressure balance between inside chamber and outside chamber, the pressure bal- ance inside the screw conveyor, and the earth input/output volume balance, which can be realized by controlling the volume of earth conveyed. 2) When the earth enters the screw conveyors, the water/soil pressure in the chamber is re- sisted by the gravity of the earth and the friction with the screw rod, lamina and the inner side of the conveyor, so as to keep stable earth conveying. 3 ) The earth behavior, which has great influence on the earth conveying and pressure maintaining of screw conveyors, can be improved by injecting ground conditioning agents into areas ahead of the cutter heads and into the chamber. 4) Regarding the structure of the screw conveyor, the pressure maintaining effect can be improved by means of reducing the pitch, adopting discontinuous screw and double screw conveyors.%螺旋输送机的排土和保压作用的发挥对土压平衡盾构的施工安全与效率有重要影响,对其作用机制及影响其作用发挥的因素进行系统的理论分析,并参考工程实测数据,得出以下结论:1)盾构施工中的土压平衡包括土仓内外与螺旋输送机内的压力平衡和进、出土量的平衡,其通过螺旋输送机排土量的控制来实现;2)渣土进入螺旋输送机后,依靠自身重力及与螺杆、叶片和筒壁界面间的摩擦作用来抵抗土仓内的水土压力,保持出渣过程的稳定性;3)渣土性质对螺旋输送机的排土和保压效果有较大影响,主要通过向刀盘前方和土仓内添加改良材料的

  19. 硅铁除尘系统中螺旋输灰机构参数的选择%SELECTION OF PARAMETERS OF SCREW CONVEYOR IN BAG HOUSE DUST COLLECTOR IN FeSi FURNACE

    Institute of Scientific and Technical Information of China (English)

    卢鹏翔

    2001-01-01

    The screw conveyor was adopted in bag house dust collector in 12.5MVA FeSi furnace,and its parameters were calculated and selected.The practice showed that the screw conveyor runned well,the service effect was good.%12.5MVA硅铁炉布袋反吸烟气净化系统中采用了螺旋输灰机构,并对输灰机构的参数进行了计算和选择。经生产中使用,螺旋输灰机运行良好,取得了较好的使用效果。

  20. Data From HANE-Generated Radiation Belts and the Origin of Diffusion Theory

    Energy Technology Data Exchange (ETDEWEB)

    Winske, Dan [Los Alamos National Laboratory

    2012-07-16

    In this presentation we briefly review some of the published data regarding the artificial radiation belts produced by the Starfish and R2 high altitude nuclear explosions in 1962. The data showed slow temporal variations of the belts in altitude (L) and pitch angle ({alpha}) that could be modeled as a diffusion process. That early work formed the basis for more complex radiation belt diffusion models that are in use at present.

  1. The "One Belt and One Road" is an Important Mutually Beneficial and Win-win Strategy

    Institute of Scientific and Technical Information of China (English)

    Long; Kaifeng

    2015-01-01

    The"One Belt and One Road"strategic conception carries the dream of development and prosperity of countries concerned,and gives the ancient Silk Road a brand new content of the time.In September and October 2013,President Xi Jinping proposed building the"New Silk Road Economic Belt"(One Belt)and the"Twenty-first Century Maritime Silk Road"(One Road)strategic conception respectively,emphasizing a mutual-beneficial and win-win

  2. Progress in porphyry copper exploration from the Gangdise belt, Tibet, China

    Institute of Scientific and Technical Information of China (English)

    ZHENG Youye; DUO Ji; CHENG Shunbo; GAO Shunbao; DAI Fanghua

    2007-01-01

    Recent mineral exploration in the Gangdise porphyry copper deposit belt, an important component of the Himalaya-Tethyan metallogenic belt, has led to the discovery of a number of deposits, as exemplified by the world-class Miocene Qulong porphyry Cu deposit. This paper reviews major advances in the studies of ore genesis and metallogenic regularity and progresses in mineral exploration of porphyry Cu deposits in the belt. Existing problems and suggestion for future exploration also are given.

  3. «Granulite» zircons of the Lapland granulite belt

    Science.gov (United States)

    Kaulina, T.

    2003-04-01

    An age of the main stage of granulite metamorphism, which followed the overthrusting of the Lapland granulite belt (LGB) is estimated at about 1.91-1.95 Ga (Tugarinov, Bibikova, 1980; Bernard-Griffiths et al., 1984; Bibikova et al., 1993; Mitrofanov et al., 1993). This high-grade metamorphism is dated by U-Pb method on short prismatic gem-quality zircons that are typical for granulites and are interpreted as formed under stress and space-shortage conditions of the high pressure. And the common belief is that these zircon ages are dating the peak conditions of a metamorphic P-T path, since zircon has a high closure temperature of its U-Pb system. We studied rocks with different degree of metamorphism from Yavr and Pados rivers district (Kola Peninsula, Russia) located in the connection zone of the Tanaelv belt and LGB. Samples from the Tanaelv belt were taken from: 1) leucocratic garnet-clinopyroxene-amphibole plagiogneiss, chemically corresponds to andesite and formed under amphibolite facies 2) leucocratic biotite-pyroxene plagiogneiss with mineral association of granulite facies. Lapland granulites are represented by sillimanite-garnet-biotite gneiss from khondalite complex and leuco-mesocratic amphibole-pyroxene-plagioschist, belonging to the charnockite complex. Metamorphic zircons in all studied samples are represented practically by crystals of the same image. These are round or isometric (rarely subidiomorphic-prismatic in mafic granulites) large crystals with bright luster and high transparency. They are colorless or weakly colored into yellowish-pinkish tones. Crystals are zoneless but may contain cores, especially zircons from khondalite, 60% of which contain zoned cores. Thus typically “granulitic” zircon, described in many works, is the dominant type both in granulites of the Lapland belt and in amphiboles gneisses of the Tanaelv belt. Zircons are distinguished by low U contents (up to 100 ppm) and high Th/U and Zr/Hf ratios (0.6-0.7 and 42

  4. The Migration Characteristics of Strong Earthquakes on the North-South Seismic Belt and Its Relation with the South Asia Seismic Belt

    Institute of Scientific and Technical Information of China (English)

    Wang Yipeng; Ma Jin; Li Chuanyou

    2008-01-01

    Migration of strong earthquakes (M≥7.0) along the North-South Seismic Belt of China since 1500 AD shows three patterns: Approximately equal time and distance interval migration from N to S, varied patterns of migration from S to N and grouped strong earthquake activity in a certain period over the entire seismic belt. Analysis of strong earthquakes in the past hundred years shows that the seismicity on the North-South Seismic Belt is also associated with strong earthquake activities on the South Asia Seismic Belt which extends from Myanmar to Sumatra, Indonesia. Strong earthquakes on the former belt often lag several months or years behind the quakes occurring on the later belt. So, after the occurrence of the December 26, 2004 M8.7 great earthquake off the western coast of Sumatra, Indonesia, the possibility of occurrence of strong earthquakes on the North-South Seismic Belt of China cannot be ignored. The above-mentioned migration characteristics of strong earthquakes are related to the northeastward collision and subduction of the India Plate as well as the interaction between the Qinghai-Xizang (Tibet) Plateau and the stable and hard Ordos and Alashan Massifs at its northeastern margin.

  5. The Design of PLC Control Programs of Screens and Spiral Conveyors%格栅除污机及螺旋输送机PLC控制程序设计

    Institute of Scientific and Technical Information of China (English)

    谢凯; 袁鹏; 王明军

    2011-01-01

    本文分析了污水提升泵站格栅除污机及螺旋输送机自动控制运行原理,以西门子S7-300系列PLC为例,设计出了PLC控制程序.%This paper analy es the automatic operation principle of screens and spiral conveyors at wastewater pumping stations,designs the PLC control programs based on S7-300 of Siemens.

  6. Design and Application of New High-pressure Sealing Screw Conveyor%新型高压密封螺旋输送机的设计与应用

    Institute of Scientific and Technical Information of China (English)

    杨丽珍; 钟少振; 张晓冬

    2011-01-01

    螺旋输送机主要用于输送各种粉状、粒状、小块状等散状物料,常用于食品、化工、煤炭、建筑 及冶炼等工业.随着新工艺新技术的发展,在化工及冶炼行业常伴有高压有毒有害气体,对螺旋输送机性能提出了新的要求.天津赛瑞机器设备有限公司为满足市场需求研发出一种适用于输送过程中伴有高压及密封要求的新型高压密封螺旋输送机.本文介绍了该高压密封螺旋输送机的主要参数、输送工艺和结构技术特点.%High-pressure sealing screw conveyor is a kind of machine for carrying materials of a variety of powder,grain and little nub, which is common in the industries of food, chemistry, coal, construction and smelting. Gencrally is accompanied with high pressure noxious gas in chemistry and smelting industry, the development of new process and technology new demands of screw conveyor's performance will be occurred. Our company researched and designed a new type of highpressure sealing screw conveyor with requirements of high-pressure and sealing to satisfy market's demand. The paper introduced the main parameter, carrying process and structure specifics of high-pressure sealing screw conveyor.

  7. Geological characteristics and metallogenic prognosis of main gold deposit in Altai gold ore belt, Xinjiang

    Institute of Scientific and Technical Information of China (English)

    SHEN Yuan-chao; SHEN Ping; ZHENG Qing-dong; LIU Tie-bing; LI Guang-ming

    2004-01-01

    Altai polymetallic mineralization belt is famous copper-polymetallic mineralization belt in the world. There are a lot of gold deposits in the Altai ore belt in Xinjiang, China. These gold deposits belong to two genetic types: volcanogene late-stage hydrothermal type and fractured altered rock type. The authors discuss mainly the geological and mineralized features of fractured altered rock type of gold deposits in Altai gold ore belt. Base on this study, the metallogenic law is summarized and the deep metallogenic prognosis has been done in Duolanasayi and Tuokuzibayi gold deposits, and some mineralized anomalys have been discovered.

  8. Triggering Sublimation-driven Activity of Main Belt Comets

    Science.gov (United States)

    Haghighipour, N.; Maindl, T. I.; Schäfer, C.; Speith, R.; Dvorak, R.

    2016-10-01

    It has been suggested that the comet-like activity of main belt comets (MBCs) is due to the sublimation of sub-surface water–ice that has been exposed as a result of their surfaces being impacted by meter-sized bodies. We have examined the viability of this scenario by simulating impacts between meter-sized and kilometer-sized objects using a smooth particle hydrodynamics approach. Simulations have been carried out for different values of the impact velocity and impact angle, as well as different target material and water-mass fractions. Results indicate that for the range of impact velocities corresponding to those in the asteroid belt, the depth of an impact crater is slightly larger than 10 m, suggesting that if the activation of MBCs is due to the sublimation of sub-surface water–ice, this ice has to exist no deeper than a few meters from the surface. Results also show that ice exposure occurs in the bottom and on the interior surface of impact craters, as well as on the surface of the target where some of the ejected icy inclusions are re-accreted. While our results demonstrate that the impact scenario is indeed a viable mechanism to expose ice and trigger the activity of MBCs, they also indicate that the activity of the current MBCs is likely due to ice sublimation from multiple impact sites and/or the water contents of these objects (and other asteroids in the outer asteroid belt) is larger than the 5% that is traditionally considered in models of terrestrial planet formation, providing more ice for sublimation. We present the details of our simulations and discuss their results and implications.

  9. DREAM3D simulations of inner-belt dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Cunningham, Gregory Scott [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-05-26

    A 1973 paper by Lyons and Thorne explains the two-belt structure for electrons in the inner magnetosphere as a balance between inward radial diffusion and loss to the atmosphere, where the loss to the atmosphere is enabled by pitch-angle scattering from Coulomb and wave-particle interactions. In the 1973 paper, equilibrium solutions to a decoupled set of 1D radial diffusion equations, one for each value of the first invariant of motion, μ, were computed to produce the equilibrium two-belt structure. Each 1D radial diffusion equation incorporated an L-and μ-dependent `lifetime' due to the Coulomb and wave-particle interactions. This decoupling of the problem is appropriate under the assumption that radial diffusion is slow in comparison to pitch-angle scattering. However, for some values of μ and L the lifetime associated with pitch-angle scattering is comparable to the timescale associated with radial diffusion, suggesting that the true equilibrium solutions might reflect `coupled modes' involving pitch-angle scattering and radial diffusion and thus requiring a 3D diffusion model. In the work we show here, we have computed the equilibrium solutions using our 3D diffusion model, DREAM3D, that allows for such coupling. We find that the 3D equilibrium solutions are quite similar to the solutions shown in the 1973 paper when we use the same physical models for radial diffusion and pitch-angle scattering from hiss. However, we show that the equilibrium solutions are quite sensitive to various aspects of the physics model employed in the 1973 paper that can be improved, suggesting that additional work needs to be done to understand the two-belt structure.

  10. Archaean greenstone belts and associated granitic rocks - A review

    Science.gov (United States)

    Anhaeusser, Carl R.

    2014-12-01

    Archaean greenstone belts and associated granitic rocks comprise some of the most diverse rock types on the Earth's surface and were formed during the early stages of the development of the planet from Eoarchaean to Neoarchaean times - a period extending back from about 4000 to 2500 million years ago. Because of their great age, these rocks have received unprecedented attention from a wide spectrum of Earth scientists striving to learn more about the evolution of the Earth, including its crust, hydrosphere, atmosphere, the commencement of life, and the nature and distribution of mineral deposits. The knowledge gained thus far has accumulated incrementally, beginning with solid field-based studies, the latter being supplemented with increasingly advanced technological developments that have enabled scientists to probe fundamental questions of Earth history. Archaean granite-greenstone terranes display considerable variability of lithologies and geotectonic events, yet there are unifying characteristics that distinguish them from other geological environments. Most greenstone belts consist of a wide variety of volcanic and sedimentary rocks that reflect different evolutionary conditions of formation and all have invariably been influenced by subsequent geotectonic factors, including the intrusion of ultramafic, mafic and granitic complexes, resulting in widespread deformation, metamorphism, metasomatism, as well as mineralization. Geochemical and isotopic age determinations have shown how complex these ancient rocks are and efforts at understanding the nature and evolution of the hydrosphere, atmosphere and primitive life have made Archaean terranes exciting environments in which to study. Conflicting views as to the nature, history and origin of many of the rock types and events in Archaean terranes has been ongoing and stimulating. This review attempts to describe the main lithotypes and other characteristics of granite-greenstone belt geology and points to some

  11. On the oldest asteroid families in the main belt

    Science.gov (United States)

    Carruba, V.; Nesvorný, D.; Aljbaae, S.; Domingos, R. C.; Huaman, M.

    2016-06-01

    Asteroid families are groups of minor bodies produced by high-velocity collisions. After the initial dispersions of the parent bodies fragments, their orbits evolve because of several gravitational and non-gravitational effects, such as diffusion in mean-motion resonances, Yarkovsky and Yarkovsky-O'Keefe-Radzievskii-Paddack (YORP) effects, close encounters of collisions, etc. The subsequent dynamical evolution of asteroid family members may cause some of the original fragments to travel beyond the conventional limits of the asteroid family. Eventually, the whole family will dynamically disperse and no longer be recognizable. A natural question that may arise concerns the time-scales for dispersion of large families. In particular, what is the oldest still recognizable family in the main belt? Are there any families that may date from the late stages of the late heavy bombardment and that could provide clues on our understanding of the primitive Solar system? In this work, we investigate the dynamical stability of seven of the allegedly oldest families in the asteroid main belt. Our results show that none of the seven studied families has a nominally mean estimated age older than 2.7 Gyr, assuming standard values for the parameters describing the strength of the Yarkovsky force. Most `paleo-families' that formed between 2.7 and 3.8 Gyr would be characterized by a very shallow size-frequency distribution, and could be recognizable only if located in a dynamically less active region (such as that of the Koronis family). V-type asteroids in the central main belt could be compatible with a formation from a paleo-Eunomia family.

  12. Extensive Admixture and Selective Pressure Across the Sahel Belt.

    Science.gov (United States)

    Triska, Petr; Soares, Pedro; Patin, Etienne; Fernandes, Veronica; Cerny, Viktor; Pereira, Luisa

    2015-11-26

    Genome-wide studies of African populations have the potential to reveal powerful insights into the evolution of our species, as these diverse populations have been exposed to intense selective pressures imposed by infectious diseases, diet, and environmental factors. Within Africa, the Sahel Belt extensively overlaps the geographical center of several endemic infections such as malaria, trypanosomiasis, meningitis, and hemorrhagic fevers. We screened 2.5 million single nucleotide polymorphisms in 161 individuals from 13 Sahelian populations, which together with published data cover Western, Central, and Eastern Sahel, and include both nomadic and sedentary groups. We confirmed the role of this Belt as a main corridor for human migrations across the continent. Strong admixture was observed in both Central and Eastern Sahelian populations, with North Africans and Near Eastern/Arabians, respectively, but it was inexistent in Western Sahelian populations. Genome-wide local ancestry inference in admixed Sahelian populations revealed several candidate regions that were significantly enriched for non-autochthonous haplotypes, and many showed to be under positive selection. The DARC gene region in Arabs and Nubians was enriched for African ancestry, whereas the RAB3GAP1/LCT/MCM6 region in Oromo, the TAS2R gene family in Fulani, and the ALMS1/NAT8 in Turkana and Samburu were enriched for non-African ancestry. Signals of positive selection varied in terms of geographic amplitude. Some genomic regions were selected across the Belt, the most striking example being the malaria-related DARC gene. Others were Western-specific (oxytocin, calcium, and heart pathways), Eastern-specific (lipid pathways), or even population-restricted (TAS2R genes in Fulani, which may reflect sexual selection).

  13. Power Consumption and Experimental Study of Maize Straw Screw Conveyor%螺旋输送装置输送玉米秸秆功耗研究

    Institute of Scientific and Technical Information of China (English)

    乌兰图雅; 王春光; 谢胜仕; 赵圆圆

    2015-01-01

    In order to reduce the power consumption of the screw conveyor and increase its conveying efficiency , the the-oretical analyzing method and experimental research were used to establish the mathematical models of the power con -sumption which suitable for the different conveying state .The effects of screw rotational speeds and the feeding rates on power consumption and productivity ratio were studied by experimental study .The results show that the conveying power consumption increases 5~9 W when the rotational speed increased 10 r/min ( filling rate is fixed value ) , and the conve-ying power consumption increases 10~12W when the filling rate increased 0.1kg/s(rotational speed is fixed value).The experimental results still prove that the screw conveyor has the highest productivity ratio :0 .704~0 .714 kg/W when the moisture content of material is 24%, the rotational speed and filling rate are 120r/min and 0.88kg/s respectively.At the same time , the mechanical properties of materials to be delivered with the change of moisture content and the effects of moisture content on the power consumption were studied .The results show that the sliding friction angle increases 3 °~5 ° when the moisture content of material is increased 10%.And the internal friction angle increase first and then decreased along with the increasing of moisture content ,and the power consumption of the screw conveyor increased 7~9 W under certain filling rate and rotational speed .%为了降低螺旋输送装置的输送功耗,提高输送效率,通过理论分析和试验研究,建立了不同输送条件下螺旋输送粗饲料功耗的数学模型,试验研究了螺旋转速及喂入量对输送装置的输送功耗和比能产量的影响。试验结果表明:转速每增加10r/min(喂入量为定值),输送装置的输送功耗增大5~9W,喂入量每增加0.1kg/s (转速为定值),输送功耗增大10~12 W;同时得知:输送含水率约24%的揉

  14. Accuracy and performance analysis of a nuclear belt weigher

    International Nuclear Information System (INIS)

    Nuclear belt weighers have a broad range of applications in the solid particle industry. This work analyzes the accuracy and sensitivity of nuclear weighers for a wide range of operational conditions and design parameters. The problem of the effect of material profile and bulk density variations on the scale performance is quantitatively addressed. A new methodology is developed to calculate the minimum detectable load accounting for both accuracy and sensitivity. Accuracies of less than 1% can be achieved in some ideal situations by proper design of the source length and geometrical configuration. (orig.)

  15. Ultra low frequency waves impact on radiation belt energetic particles

    Institute of Scientific and Technical Information of China (English)

    ZONG QiuGang; HAO YongQiang; WANG YongFu

    2009-01-01

    One of the most fundamental important issues in the space physics is to understand how solar wind energy transports into the inner magnetosphere.Ultra low frequency(ULF)wave in the magnetosphere and its impact on energetic particles,such as the wave-particle resonance,modulation,and particle acceleration,are extremely important topics in the Earth's radiation belt dynamics and solar windmagnetospheric coupling.In this review,we briefly introduce the recent advances on ULF waves study.Further,we will explore the density structures and ion compositions around the plasmaspheric boundary layer(PBL)and discuss its possible relation to the ULF waves.

  16. Rapid energization of radiation belt electrons by nonlinear wave trapping

    Directory of Open Access Journals (Sweden)

    Y. Katoh

    2008-11-01

    Full Text Available We show that nonlinear wave trapping plays a significant role in both the generation of whistler-mode chorus emissions and the acceleration of radiation belt electrons to relativistic energies. We have performed particle simulations that successfully reproduce the generation of chorus emissions with rising tones. During this generation process we find that a fraction of resonant electrons are energized very efficiently by special forms of nonlinear wave trapping called relativistic turning acceleration (RTA and ultra-relativistic acceleration (URA. Particle energization by nonlinear wave trapping is a universal acceleration mechanism that can be effective in space and cosmic plasmas that contain a magnetic mirror geometry.

  17. Ultra low frequency waves impact on radiation belt energetic particles

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    One of the most fundamental important issues in the space physics is to understand how solar wind energy transports into the inner magnetosphere.Ultra low frequency(ULF)wave in the magnetosphere and its impact on energetic particles,such as the wave-particle resonance,modulation,and particle acceleration,are extremely important topics in the Earth’s radiation belt dynamics and solar wind― magnetospheric coupling.In this review,we briefly introduce the recent advances on ULF waves study. Further,we will explore the density structures and ion compositions around the plasmaspheric boundary layer(PBL)and discuss its possible relation to the ULF waves.

  18. Determination of Flutter Derivatives for the Great Belt Bridge

    DEFF Research Database (Denmark)

    Poulsen, Niels Kjølstad; Damsgaard, Aage; Reinhold, Thim A.

    1992-01-01

    A new method which combines control theory and system identification techniques has been used to extract flutter derivatives from section model tests for the Great Belt East Bridge. Tests were conducted by exciting the section model simultaneously in vertical and torsional modes of vibration. Tests...... were primarily conducted in smooth flow for various ratios between vertical and torsional frequencies of vibration. Limited testing was also conducted in turbulent flow and for different angles of attack. The analysis technique described allowed extraction of seven aerodynamic derivatives including...

  19. Horizontal-belt filtration at Randfontein Estates Mine

    International Nuclear Information System (INIS)

    The paper describes tests on horizontal-belt filters for the filtration of gold and uranium. The promising results led to the installation of 17 such filters (ten of them 120 m2 in size) in the mine's metallurgical plants, and their operation is discussed. Although several problems were encountered both in operation and maintenance, it is concluded that, with correct operation and suitable filter cloths, exceptionally good metallurgical recoveries can be achieved at filtration rates twice to three times higher than those on rotary filters

  20. Radial diffusion of radiation belt electrons in three dimensions

    Science.gov (United States)

    Perry, Kara Lynn

    It is becoming increasingly important to understand the dynamics of radiation belt energetic particles given their potentially hazardous effects on satellites and our ever-increasing dependence on those satellites. There is a need to determine whether existing two-dimensional models are adequate in estimating the dynamics of the radiation belts or if a three-dimensional model is required. Discussion of general space physics and radiation belt topology is followed by an account of existing models and how these models can be improved by extending dynamic calculations from two dimensions to three. A model is then developed describing magnetic and electric fields associated with poloidal mode Pc5 ULF waves. The frequency and L dependence of the ULF wave power is included in this model by incorporating published ground-based magnetometer data. The influence of ultra low frequency (ULF) waves in the Pc5 frequency range on radiation belt electrons in a dipole magnetic field is examined. This is the first analysis in three dimensions utilizing model ULF wave electric and magnetic fields in the guiding center trajectories of relativistic electrons. It is demonstrated here that realistic spectral characteristics play a significant role in the rate of diffusion of relativistic electrons via drift resonance with poloidal mode ULF waves. Radial diffusion rates including bounce motion are calculated for alphaeq ≥ 50° (lambda ≤ 20°). Energy, L and pitch angle dependence of diffusion rates are calculated for L-independent, L-dependent, frequency independent and frequency dependent field power. During geomagnetic storms when ULF wave power is increased, ULF waves are a significant driver of increased fluxes of relativistic electrons inside geosynchronous orbit. Diffusion time scales obtained here, when frequency and L dependence compared to observations of ULF wave power is included, support this conclusion. A compression is then added to the dipole field model and diffusion

  1. WFIRST Ultra-Precise Astrometry I: Kuiper Belt Objects

    CERN Document Server

    Gould, Andrew

    2014-01-01

    I show that the WFIRST microlensing survey will enable detection and precision orbit determination of Kuiper Belt Objects (KBOs) down to H_vega=28.2 over an effective area of about 17 square deg. Typical fractional period errors will be ~1.5% X 10^{0.4(H-28.2)} with similar errors in other parameters for roughly 5000 KBOs. Binary companions to detected KBOs can be detected to even fainter limits, H_vega=29, corresponding to R~31 and effective diameters D~7.5 km. This will provide an unprecedented probe of orbital resonance and KBO mass measurements.

  2. 刮板输送机联接罩筒的计算和分析%Calculation and Analysis Scraper Conveyor Tube Connecting the Hood

    Institute of Scientific and Technical Information of China (English)

    谢地; 卫星

    2014-01-01

    The coupling cap tube coupling plays an important role in the scraper conveyor, crusher and other downhole equipment transmission devices. However, in the actual design process, because of its shape and force the situation is more complicated, and not be calculated, but based on past experience on the size previously used the analogy of the coupling cap tube, and then extended on the basis of its or thickened, this is bound to cause some waste, but also can not quantify the performance of the coupling cover. To a certain type scraper conveyor drive unit coupling cover cylinder example, according to its sides the forces, its overall strength, stiffness and weld calculation method of local life and stability to sort out, and according to the force case the finite element model, the calculated results were analyzed and compared.%联接罩筒在刮板输送机、破碎机等井下设备传动装置中起着重要的联接作用。但是,在实际设计过程中,由于其外形和受力情况较为复杂,并没有对其进行计算,而是根据以往经验在以前用过的联接罩筒的尺寸上进行类比,然后在其基础上加长或加厚,这样势必会造成一定的浪费,同时,也不能具体量化联接罩的性能。以某型号刮板输送机传动装置中的联结罩筒为例,根据其两边受力情况,对其整体的强度、刚度和焊缝寿命以及局部稳定性方面的计算方法进行梳理,并根据受力情况建立有限元模型,将计算结果进行分析和比较。

  3. Architecture and Channel-Belt Clustering in the Fluvial lower Wasatch Formation, Uinta Basin, Utah

    Science.gov (United States)

    Pisel, J. R.; Pyles, D. R.; Bracken, B.; Rosenbaum, C. D.

    2013-12-01

    The Eocene lower Wasatch Formation of the Uinta Basin contains exceptional outcrops of low net-sand content (27% sand) fluvial strata. This study quantitatively documents the stratigraphy of a 7 km wide by 300 meter thick strike-oriented outcrop in order to develop a quantitative data base that can be used to improve our knowledge of how some fluvial systems evolve over geologic time scales. Data used to document the outcrop are: (1) 550 meters of decimeter to half meter scale resolution stratigraphic columns that document grain size and physical sedimentary structures; (2) detailed photopanels used to document architectural style and lithofacies types in the outcrop; (3) thickness, width, and spatial position for all channel belts in the outcrop, and (4) directional measurements of paleocurrent indicators. Two channel-belt styles are recognized: lateral and downstream accreting channel belts; both of which occur as either single or multi-story. Floodplain strata are well exposed and consist of overbank fines and sand-rich crevasse splay deposits. Key upward and lateral characteristics of the outcrop documented herein are the following. First, the shapes of 243 channels are documented. The average width, thickness and aspect ratios of the channel belts are 110 m, 7 m, and 16:1, respectively. Importantly, the size and shape of channel belts does not change upward through the 300 meter transect. Second, channels are documented to spatially cluster. 9 clusters are documented using a spatial statistic. Key upward patterns in channel belt clustering are a marked change from non-amalgamated isolated channel-belt clusters to amalgamated channel-belt clusters. Critically, stratal surfaces can be correlated from mudstone units within the clusters to time-equivalent floodplain strata adjacent to the cluster demonstrating that clusters are not confined within fluvial valleys. Finally, proportions of floodplain and channel belt elements underlying clusters and channel belts

  4. Triggering Sublimation-Driven Activity of Main Belt Comets

    CERN Document Server

    Haghighipour, Nader; Schaefer, Christoph; Speith, Roland; Dvorak, Rudolf

    2016-01-01

    It has been suggested that the comet-like activity of Main Belt Comets are due to the sublimation of sub-surface water-ice that has been exposed as a result of their surfaces being impacted by m-sized bodies. We have examined the viability of this scenario by simulating impacts between m-sized and km-sized objects using a smooth particle hydrodynamics approach. Simulations have been carried out for different values of the impact velocity and impact angle as well as different target material and water-mass fraction. Results indicate that for the range of impact velocities corresponding to those in the asteroid belt, the depth of an impact crater is slightly larger than 10 m suggesting that if the activation of MBCs is due to the sublimation of sub-surface water-ice, this ice has to exist no deeper than a few meters from the surface. Results also show that ice-exposure occurs in the bottom and on the interior surface of impact craters as well as the surface of the target where some of the ejected icy inclusions...

  5. Study of the NWC electrons belt observed on DEMETER Satellite

    CERN Document Server

    Li, Xinqiao; Wang, Ping; Wang, Huanyu; Lu, Hong; Zhang, Xuemin; Huang, Jianping; Shi, Feng; Yu, Xiaoxia; Xu, Yanbing; Meng, Xiangcheng; Wang, Hui; Zhao, Xiaoyun; Parrot, M

    2010-01-01

    We analyzed the data from 2007 to 2008, which is observed by IDP onboard DEMETER satellite, during ten months of NWC working and seven months of NWC shutdown. The characteristic of the space instantaneous electron belts, which come from the influence of the VLF transmitted by NWC, is studied comprehensively. The main distribution region of the NWC electron belts and the flux change are given. We also studied the distribution characteristic of the average energy spectrum in different magnetic shell at the height of DEMETER orbit and the difference of the average energy spectrum of the electrons in the drift loss-cone between day and night. As a result, the powerful power of NWC transmitter and the 19.8 kHz narrow bandwidth VLF emission not only created a momentary electrons enhancement region, which strides 180 degree in them longitude direction and from 1.6 to 1.9 in L value, with the rise of the electrons flux reaching to 3 orders of magnitude mostly, but also induced the enhancement or loss of electrons in ...

  6. A Method for Determining Sedimentary Micro-Facies Belts Automatically

    Institute of Scientific and Technical Information of China (English)

    Linfu Xue; Qitai Mei; Quan Sun

    2003-01-01

    It is important to understand the distribution of sedimentary facies, especially the distribution of sand body that is the key for oil production and exploration. The secondary oil recovery requires analyzing a great deal of data accumulated within decades of oil field development. At many cases sedimentary micro-facies maps need to be reconstructed and redrawn frequently, which is time-consuming and heavy. This paper presents an integrated approach for determining the distribution of sedimentary micro-facies, tracing the micro-facies boundary, and drawing the map of sedimentary micro-facies belts automatically by computer technique. The approach is based on the division and correlation of strata of multiple wells as well as analysis of sedimentary facies. The approach includes transform, gridding, interpolation, superposing, searching boundary and drawing the map of sedimentary facies belts, and employs the spatial interpolation method and "worm" interpolation method to determine the distribution of sedimentary micro-facies including sand ribbon and/or sand blanket. The computer software developed on the basis of the above principle provides a tool for quick visualization and understanding the distribution of sedimentary micro-facies and reservoir. Satisfied results have been achieveed by applying the technique to the Putaohua Oil Field in Songliao Basin, China.

  7. Polyphase thrust tectonic in the Barberton greenstone belt

    Science.gov (United States)

    Paris, I. A.

    1986-01-01

    In the circa 3.5 by-old Barberton greenstone belt, the supracrustal rocks form a thick and strongly deformed thrust complex. Structural studies in the southern part of the belt have shown that 2 separate phases of over-thrusting (D sub 1 and D sub 2) successively dismembered the original stratigraphy. Thrust nappes were subsequently refolded during later deformations (D sub 3 and D sub 4). This report deals with the second thrusting event which, in the study region appears to be dominant, and (unlike the earlier thrusting), affects the entire supracrustal pile. The supracrustal rocks form a predominantly NE/SW oriented, SE dipping tectonic fan (the D sub 2 fan) in which tectonic slices of ophiolitic-like rocks are interleaved with younger sedimentary sequences of the Diepgezet and malalotcha groups. Structural and sedimentological data indicate that the D sub 2 tectonic fan was formed during a prolonged, multi-stage regional horizontal shortening event during which several types of internal deformation mechanisms were successively and/or simultaneously active. Movement appears to have been predominantly to the NW and to the N. During D sub 2, periods of quiescence and sedimentation followed periods of thrust propagation. Although the exact kinematics which led to the formation of this fan is not yet known, paleoenvironmental interpretations together with structural data suggest that D sub 2 was probably related to (an) Archean collision(s).

  8. Finding the Faintest Exozodi and Asteroid Belt Analogs in WISE

    Science.gov (United States)

    Patel, Rahul; Metchev, S.; Heinze, A.

    2014-01-01

    The presence of circumstellar dust in the terrestrial planet zone and asteroid belt regions of stars can be ascertained from the excess flux from main sequence stars in the near to mid-infrared wavelengths. Finding dust in these regions around stars is significant as it traces material related to terrestrial planet formation. In this study, we use the WISE All-Sky Survey data to detect circumstellar debris disks at the 12 and 22 μm bandpasses (W3 and W4, respectively). We present the detection of a sample of over 220 exozodi and asteroid belt analog candidates, 74% of which are brand new detections all at confidence levels >95%. This was done by cross-matching Hipparcos main-sequence stars with the WISE All-Sky Data Release for stars within 75 pc and outside the galactic plane (|b|>5°) and then seeking color excesses at W3 and W4. In addition to applying the standard WISE photometric flags and filters to remove contaminants from our sample, we also improved our selection techniques by correcting for previously unknown systematic behavior in the WISE photometry. Our debris disk candidates are reliable detections as well as unprecedentedly faint, due in large part to these improved selection techniques.

  9. Main-Belt Comet P/2012 T1 (PANSTARRS)

    CERN Document Server

    Hsieh, Henry H; Novakovic, Bojan; Yang, Bin; Haghighipour, Nader; Micheli, Marco; Denneau, Larry; Fitzsimmons, Alan; Jedicke, Robert; Kleyna, Jan; Veres, Peter; Wainscoat, Richard J; Ansdell, Megan; Elliott, Garrett T; Keane, Jacqueline V; Meech, Karen J; Moskovitz, Nicholas A; Riesen, Timm E; Sheppard, Scott S; Sonnett, Sarah; Tholen, David J; Urban, Laurie; Kaiser, Nick; Chambers, K C; Burgett, William S; Magnier, Eugene A; Morgan, Jeffrey S; Price, Paul A

    2013-01-01

    We present initial results from observations and numerical analyses aimed at characterizing main-belt comet P/2012 T1 (PANSTARRS). Optical monitoring observations were made between October 2012 and February 2013 using the University of Hawaii 2.2 m telescope, the Keck I telescope, the Baade and Clay Magellan telescopes, Faulkes Telescope South, the Perkins Telescope at Lowell Observatory, and the Southern Astrophysical Research (SOAR) telescope. The object's intrinsic brightness approximately doubles from the time of its discovery in early October until mid-November and then decreases by ~60% between late December and early February, similar to photometric behavior exhibited by several other main-belt comets and unlike that exhibited by disrupted asteroid (596) Scheila. We also used Keck to conduct spectroscopic searches for CN emission as well as absorption at 0.7 microns that could indicate the presence of hydrated minerals, finding an upper limit CN production rate of QCN100 Myr and is unlikely to be a rec...

  10. The Distribution of Basaltic Asteroids in the Main Belt

    CERN Document Server

    Moskovitz, Nicholas A; Gaidos, Eric; Willman, Mark; Nesvorny, David; Fevig, Ronald; Ivezic, Zeljko

    2008-01-01

    We present the observational results of a survey designed to target and detect asteroids whose colors are similar to those of Vesta family members and thus may be considered as candidates for having a basaltic composition. Fifty basaltic candidates were selected with orbital elements that lie outside of the Vesta dynamical family. Optical and near-infrared spectra were used to assign a taxonomic type to 11 of the 50 candidates. Ten of these were spectroscopically confirmed as V-type asteroids, suggesting that most of the candidates are basaltic and can be used to constrain the distribution of basaltic material in the Main Belt. Using our catalog of V-type candidates and the success rate of the survey, we calculate unbiased size-frequency and semi-major axis distributions of V-type asteroids. These distributions, in addition to an estimate for the total mass of basaltic material, suggest that Vesta was the predominant contributor to the basaltic asteroid inventory of the Main Belt, however scattered planetesim...

  11. Future Rangeland Ecosystems in the Dryland Belt of Asia

    Science.gov (United States)

    Qi, Jiaguo

    2015-04-01

    One of the greatest challenges humans are facing is sustainably managing water and land resources under changing global environment. This issue is especially pertinent in dryland belt in Asia where freshwater is scarce and shared among many nations. The region is heavily dependent on the diminishing Himalayan glaciers and limited and changing precipitation patterns. With increasing climate variability and a regional warming trend water security issues are acute and if not properly addressed could affect regional stability and lead to international conflicts. Solutions to these urgent regional issues are lacking and further research efforts are needed. Adaptive strategies addressing the complex and multifaceted water resource issues in the region will require a co-design and co-delivery of knowledge specific to the region and must consider exogenous factors such as policies of neighbouring countries and changing precipitation patterns due to climate change. There is a need to determine and fund scientific research priorities and practical approaches co-developed by local stakeholders and scientists to change the region's paradigm to "science for society". This presentation will summarize the collective outcome from a focused group discussion at the international workshop on "Future Earth and Science for Society" to be held from February 25-27, 2015 at Michigan State University, including knowledge gaps, research priorities, a general framework and international collaborations to move forward to addressing the future of the dyrland belt of Asia.

  12. Main-Belt Comet 238P/Read Revisited

    CERN Document Server

    Hsieh, Henry H; Pittichova, Jana

    2011-01-01

    We present a series of observations of the return of activity in main-belt comet 238P/Read. Using data obtained in July and August 2010 when 238P appeared to be largely inactive, we find best-fit IAU phase function parameters of H=19.05+/-0.05 mag, corresponding to a nucleus radius of r_n ~ 0.4 km (assuming an albedo of p_R=0.05), and G=-0.03+/-0.05. Observations from September 2010 onward show a clear rise in activity, causing both a notable change in visible morphology and increasing photometric excesses beyond what would be expected based on bare nucleus observations. By the end of the observing period reported on here, the dust mass in the coma shows indications of reaching a level comparable to that observed in 2005, but further observations are highly encouraged once 238P again becomes observable from Earth in mid-2011 to confirm whether this level of activity is achieved, or if a notable decrease in activity strength compared to 2005 can be detected. Comet 238P is now the second main-belt comet (after ...

  13. Paleoproterozoic postcollisional magmatic belt of the southern Siberian craton

    Science.gov (United States)

    Salnikova, E. B.; Larin, A. M.; Kotov, A. B.; Levitsky, V. I.; Reznitsky, L. Z.; Kovach, V. P.; Yakovleva, S. Z.

    2003-04-01

    Paleoproterozoic time is characterized by large-scale collisional and postcollisional magmatic activity evidenced in the most of ancient cratons. This global event is related to the Arctic supercontinent assemblage (Rogers, 1996). The formation of postcollisional magmatic belt at 1.9-1.8 Ga within the south-west flanking of the Siberian craton is a remarkable example of these processes happened during overall lithospheric convergence. This belt is extends for about 3000 km from the southern Enisey ridge at the west to the central Aldan shield at the east. Within the central Aldan shield the latest collisional event occurred 1925+/-5 Ma (Kotov et al, 2003) and post-collisional subalkaline S- and I-type granites emplaced at 1916+/-10 Ma (Bibikova et al., 1989), 1901+/-1 Ma (Frost et al., 1998) and 1899+/-6 Ma (Kotov et al, 2003). However at the southern Olekma terrain (western Aldan shield) the syncollisional granites have formed at 1906+/-4 Ma and postcollisional Kodar granitoids were generated at 1876-1873 Ma (Larin et al., 2000). The is a tendency outlined in timing of postcollision processes to the west (in modern coordinates). Ages of postcollisional Kevakta granitoid plutons (1846+/-8 Ma) and volcanics of North-Baikal volcano-plutonic belt (1869+/-6 Ma 1856+/-3 Ma), Baikal folded area, support this tendency. Emplacement of the Primorsky complex postcollisional rapakivi-type granitoids (southern Baikal lake) occurred at 1859+/-16 Ma (Donskaya et al., 2002). New results of U-Pb single zircon and baddeleyite dating demonstrate that formation of late-synkinematic syenite, charnockite and pegmatitic veins (1856±12 Ma, 1853±20 Ma) and calciphyre (1868±2 Ma) within the eastern part of the Sharyzhalgay block (southern Baikal lake) occurred virtually within the same episode. Postcollisional intrusive charnockite of the Shumikha complex from the western Sharyzhalgay block dated at 1861±1 Ma (Donskaya et al., 2001) and 1871±17 Ma (Levitsky et al., 2002). Subalcaline

  14. 粒煤螺旋输送特性实验研究%Screw conveying characteristics of granular coal from screw conveyor

    Institute of Scientific and Technical Information of China (English)

    陈汝超; 陈晓平; 蔡佳莹; 刘道银; 梁财

    2012-01-01

    The screw conveying characteristics of granular coal from an screw conveyor was investigated.The results show that coal particle size,moisture content and conveying angle have significant effects on the screw conveying characteristics of granular coal.Screw velocity increases with the increasing of particle size of granular coal and decreases with the increasing of moisture content of granular coal.Increasing the conveying angle leads to serious sliding of the granular coal,and the filling coefficient increases.The filling coefficient increases with the increasing of particle size and moisture content of granular coal.%在自行设计的粒煤螺旋输送系统上对粒煤的螺旋输送特性进行了研究。结果表明:粒煤的粒径、外水分及螺旋倾角对其输送特性有显著影响。粒煤的平均粒径越大,外水分越小,其输送速率越大;螺旋倾角越大,输送过程中物料的滑移现象越严重,填充系数越大;粒煤的外水分越大,平均粒径越大,输送过程中的填充系数越大。

  15. Analysis on Oil Seal Leakage for Sprocket Assembly of Armored Face Conveyors%刮板输送机链轮轴组油封漏油分析

    Institute of Scientific and Technical Information of China (English)

    朱秀梅

    2014-01-01

    Armored face conveyor works in bad environment.Its floating oil seal installed in sprocket assembly is always failed and causes oil leakage,which may cause the lubricating oil waste and pollute the work environment,and even cause the damage of the bearing inside sprocket assembly.Various factors caused seal failure were analyzed from the quality of sprocket assembly floating oil seal,component installation,the habits of users and other aspects.It has a certain reference role to improve the seal reliability in sprocket assembly.%刮板输送机工作环境恶劣,其链轮轴组的浮动油封经常失效导致漏油,轻则造成润滑油浪费、工作环境被污染,重则导致链轮轴组内轴承损坏。从链轮轴组浮动油封自身质量、组件安装、用户使用等各环节对造成密封失效的各种因素进行分析,对提高链轮轴组密封可靠性有一定参考作用。

  16. Design the assembly shop of wide plate conveyor line%总装车间宽板输送线设计

    Institute of Scientific and Technical Information of China (English)

    李彬; 王迎斌; 岳小兵

    2016-01-01

    文章主要结合蒙城项目 OK 线宽板链输送线自主非标设计来阐述整个宽板输送线的非标设计详细流程、电机减速机选型校核及其他主要组成部件受力强度的安全校核等内容,有利于提高总装装配人员的非标设计能力、节约设计成本。%This paper mainly with Mengcheng project OK width plate chain conveyor line independent non-standard design to explain the whole wide board conveying line non-standard design process, motor reducer selection check and other major components of stress strength safety checking and other content, is beneficial to improving the General Assembly staff non-standard design capability, saving the cost of design.

  17. The optimal design to the chain of pallet conveyors%平板输送机链条的优化设计

    Institute of Scientific and Technical Information of China (English)

    杨志斌

    2013-01-01

    The chain of ordinary pallet conveyor, consisted of roller sleeve chain with K-shaped accessory and steel squared pipe, moves at rolling and sliding between roller and the guide rail when load motion, so the power consumption is comparatively large. In this article was introduced the redesign of the roller structure, the needle roller bearing was equipped in the roller to change supporting motion into simple rolling motion, with the friction loading and main power consumption reduced.%普通平板输送机的链条,由带K型附件的滚子套筒链和方管钢组成,该链条在负载运行时,滚子和链条导轨之间是滚动兼滑动的摩擦运动形式,所消耗的动力功率较大。本文以该问题为切入点,重新设计了滚子结构,在滚子里面加装滚针轴承,使支撑运动形式变为了纯滚动,减小了运动中链条的摩擦负载,降低了主动功耗。

  18. Evaluation of variations in CO2 gas exchange in the atmosphere of the BTLSS with plants grown in a conveyor mode on the soil-like substrate

    Science.gov (United States)

    Velichko, Vladimir; Tikhomirov, Alexander A.; Tikhomirova, Natalia; Ushakova, Sofya

    2016-07-01

    The soil-like substrate (SLS) included in the bioregenerative life support system (BLSS) exerts a substantial effect on its gas exchange. This effect is determined by the non-uniform rate of organic matter degradation in the SLS, on the one hand, and by the variable intensity of photosynthesis of the plants grown on it, on the other. The purpose of this study was to compare CO2 variations in the atmosphere of the higher plants - SLS system at different intervals in uneven-aged higher plant conveyers. The study showed that CO2 concentration could reach and exceed the levels of atmospheric carbon dioxide acceptable for humans (over 1%) even when the conveyer interval was rather short. CO2 variations in the atmosphere of the higher plants - SLS system were determined not only by the frequency of adding plant waste to the SLS and the mass of the waste but also by the amount of the harvested actively photosynthesizing plant biomass. At the same time, no significant differences were found in the mineral and production components between the plants in different experiments. Results of the study can be used to optimize the conveyor interval and the associated effectiveness of mineralization of the plant waste added to the SLS and to stabilize the CO2 gas exchange. This study was carried out in the IBP SB RAS and supported by the grant of the Russian Science Foundation (Project No. 14-14-00599).

  19. Northwest trending tectonic belt in the middle Yanshan Orogenic Belt of northeast Hebei Province, North China:Tectonic evolution and geochronology

    Institute of Scientific and Technical Information of China (English)

    ZHANG; Changhou; WU; Ganguo; WANG; Genhou; ZHANG; Weijie

    2004-01-01

    The northwest trending tectonic belt in the middle part of the Mesozoic intraplate Yanshan Orogenic Belt, northeast Hebei Province, is composed of thrusts, extensional faults,strike-slip faults and syntectonic sedimentations as well. The northeastward basement-involved major thrusting deformation occurred between 174Ma and 168MaBP and was followed by an intrusion of the granitic plutonic rocks. As a part of the post-thrusting extensional deformations a northwest extending volcano-sedimentation system of Late Jurassic and Early Cretaceous formed in the southwest side of the belt. These volcano-sedimentary sequences are divided into Tuchengzi Formation, Zhangjiakou Formation, Yixian Formation and Jiufotang Formation respectively. They are characterized by southeastward migration as a result of the increasing down-dip slip displacement along the major extensional fault toward the southeast of the belt.The provenance area of the Jiufotang Formation north to it experienced southwestward thrusting during and after its later sedimentation. The thrusting in this stage resulted in the formation of an asymmetric footwall syncline with vergence to SW in the Jiufotang Formation in the NE side of the basin. Finally a dextral strike-slip deformation occurred along the NW tectonic belt. The striking tectono-geomorphological features and present seismic activities along this belt indicate that it has been being active since Cenozoic era and is still in the active state at present. This northwest extending tectonic belt was following the same direction and location as the existing fault systems within the basement as revealed by former geological and geophysical studies. So it is reasonable to infer the Mesozoic deformation along this belt to be a result of reactivation of the basement structures in a favorable tectonic stress field. The reactivation of basement structures might be taken as one of the mechanisms of intraplate deformation and orogeny.

  20. A mathematical analysis of a belt system with a low and time-varying velocity

    NARCIS (Netherlands)

    Suweken, Gede

    2003-01-01

    In this thesis a mathematical analysis has been given for model which describes the transversal vibrations of belt systems. The belt speed is assumed to be time-varying and to be small compared to the wave speed. Not only linear string-like or beam-like models but also nonlinear models have been stu

  1. Planck intermediate results. XII: Diffuse Galactic components in the Gould Belt System

    DEFF Research Database (Denmark)

    Planck Collaboration,; Ade, P. A. R.; Aghanim, N.;

    2013-01-01

    We perform an analysis of the diffuse low-frequency Galactic components in the Southern part of the Gould Belt system (130^\\circ\\leq l\\leq 230^\\circ and -50^\\circ\\leq b\\leq -10^\\circ). Strong ultra-violet (UV) flux coming from the Gould Belt super-association is responsible for bright diffuse...

  2. Thrust Belts and Foreland Basins——SGF/SGE Joint Earth Science Meeting

    Institute of Scientific and Technical Information of China (English)

    Olivier Lacombe; Jér(o)me Lavé; Fran(c)ois Roure

    2006-01-01

    @@ What is the important geologic information that thrust belts and foreland basins have recorded on the erogenic evolution of adjacent mountain belts? How can they reveal the coupled influence of deep (flexure, plate rheology and kinematics) and surficial (erosion, sedimentation) geological processes?

  3. Lithofacies Associations and Depositional Environments of the Neogene Molasse succession, Pishin Belt, northwestern Pakistan

    DEFF Research Database (Denmark)

    Kasi, Aimal K.; Kassi, Akhtar M.; Friis, Henrik;

    The Pishin Belt is a NE-SW trending mixed flysch and molasse basin, situated at the northwestern part of Pakistan, bordered by Afghan Block of the Eurasian Plate in the west and Indian Plate in the east. Western boundary of the belt is marked by the well-known Chaman Transform Fault, whereas the ...

  4. Illicit Drug Use and the Social Context of HIV/AIDS in Alabama's Black Belt

    Science.gov (United States)

    Lichtenstein, Bronwen

    2007-01-01

    Context: The rural Black Belt of Alabama is among the poorest areas of the nation. Poverty, lack of health infrastructure, and health disparities involving HIV/AIDS and other diseases reflect the lower life expectancy of people in the region. The Black Belt region has the highest HIV rates in rural America. Purpose: Using Alabama as a case…

  5. The sedimentary dynamics in natural and human-influenced delta channel belts

    NARCIS (Netherlands)

    Hobo, N.

    2015-01-01

    This study investigates the increased anthropogenic influence on the within-channel belt sedimentary dynamics in the Rhine delta. To make this investigation, the sedimentary dynamics within the life-cycle of a single channel belt were reconstructed for three key periods of increasing human impact, w

  6. 77 FR 30885 - Clarification of Prior Interpretations of the Seat Belt and Seating Requirements for General...

    Science.gov (United States)

    2012-05-24

    ... Airplane Flight Manual (14 CFR 23.1581(j)). See 36 FR 12511; see also 14 CFR 23.562, 23.785; Legal... 121, part 91 did not require that each person have a separate seat and/or seat belt. See 36 FR 12511... Belt and Seating Requirements for General Aviation Flights AGENCY: Federal Aviation Administration...

  7. Critical taper wedge mechanics of fold-and-thrust belts on Venus - Initial results from Magellan

    Science.gov (United States)

    Suppe, John; Connors, Chris

    1992-01-01

    Examples of fold-and-thrust belts from a variety of tectonic settings on Venus are introduced. Predictions for the mechanics of fold-and-thrust belts on Venus are examined on the basis of wedge theory, rock mechanics data, and currently known conditions on Venus. The theoretical predictions are then compared with new Magellan data.

  8. Triggering Comet-Like Activity of Main Belt Comets

    Science.gov (United States)

    Haghighipour, Nader; Maindl, Thomas I.; Schaefer, Christoph; Speith, Roland; Dvorak, Rudolf

    2016-10-01

    Main-belt comets (MBCs) have attracted a great deal of interest since their identification as activated asteroids by Hsieh and Jewitt in 2006. It has been suggested that the comet-like activity of these objects are due to the sublimation of sub-surface water-ice that has been exposed as a result of their surfaces being impacted by small (e.g, m-sized) bodies. We have examined the viability of this scenario by simulating impacts between m-sized impactors and km-sized targets using a smooth particle hydrodynamics (SPH) approach. We have carried out simulations for a range of impact velocities and angles, material type and strength, and water content of the target allowing m-sized impactors to erode enough of an MBC's surface to trigger its activation. Results indicate that for the range of impact velocities corresponding to those in the asteroid belt, the depth of an impact crater is slightly larger than 10 m suggesting that if the activation of MBCs is due to the sublimation of sub-surface water-ice, this ice has to exist no deeper than a few meters from the surface. Our simulations point to a clearly notable spread in the aggregated crater depths due to different impact energy, impact angles, and MBC's water contents showing deeper craters due to less overall material strength. Results also show that ice-exposure occurs in the bottom and on the interior surface of impact craters as well as the surface of the target where some of the ejected icy inclusions are re-accreted. Our results, in addition to demonstrating that the impact scenario is indeed a viable mechanism to expose ice and trigger the activity of MBCs, indicate that the activity of the current MBCs is likely due to ice sublimation from multiple impact sites and/or the water contents of these objects (and other asteroids in the outer asteroid belt) is larger than the 5% that is traditionally considered in models of terrestrial planet formation. We present details of our simulations and discuss their

  9. Photometry of Main Belt and Trojan asteroids with K2

    Science.gov (United States)

    Szabó, Gyula; Kiss, Csaba; Pal, Andras; Szabo, Robert

    2016-10-01

    Due to the failure of the second reaction wheel, a new mission was conceived for the otherwise healthy Kepler space telescope. In the course of the K2 Mission, the telescope is staring at the plane of the Ecliptic, hence thousands of Solar System bodies cross the K2 fields, usually causing extra noise in the highly accurate photometric data.We could measure the first continuous asteroid light curves, covering several days wthout interruption, that has been unprecedented to date. We studied the K2 superstamps covering the M35 and Neptune/Nereid fields observed in the long cadence (29.4-min sampling) mode. Asteroid light curves are generated by applying elongated apertures. We investigated the photometric precision that the K2 Mission can deliver on moving Solar System bodies, and determined the first uninterrupted optical light curves of main-belt and Trojan asteroids. We use thed Lomb-Scargle method to find periodicities due to rotation.We derived K2 light curves of 924 main-belt asteroids in the M35 field, and 96 in the path of Neptune and Nereid. Due to the faintness of the asteroids and the high density of stars in the M35 field, 4.0% of the asteroids with at least 12 data points show clear periodicities or trend signalling a long rotational period, as opposed to 15.9% in the less crowded Neptune field. We found that the duty cycle of the observations had to reach ˜ 60% in order to successfully recover rotational periods.The derived period-amplitude diagram is consistent to the known distribution of Main Belt asteroids. For Trojan asteroids, the contribution of our 56 objects with newly determined precise period and amplitude is in the order of all previously known asteroids. The comparison with earth-based determinations showed a previous bias toward short periods and has also proven that asteroid periods >20 hour can be unreliable in a few cases because of daylight time and diurnal calibrations. These biases are avoided from the space. We present an unbiased

  10. Periodic responses of a pulley-belt system with one-way clutch under inertia excitation

    Science.gov (United States)

    Ding, Hu

    2015-09-01

    The stable steady-state periodic response of a two-pulley belt drive system coupled with an accessory by a one-way clutch is presented. For the first time, the pulley-belt system is studied under double excitations. Specifically, the dual excitations consist of harmonic motion of the driving pulley and inertia excitation. The belt spans are modeled as axially moving viscoelastic beams by considering belt bending stiffness. Therefore, integro-partial-differential equations are derived for governing the transverse vibrations of the belt spans. Moreover, the transverse vibrations of the moving belt are coupled with the rotation vibrations of the pulleys by nonlinear dynamic tension. For describing the unidirectional decoupling function of the one-way device, rotation vibrations of the driven pulley and accessory are modeled as coupled piecewise ordinary differential equations. In order to eliminate the influence of the boundary of the belt spans, the non-trivial equilibriums of the pulley-belt system are numerically determined. Furthermore, A nonlinear piecewise discrete-continuous dynamical system is derived by introducing a coordinate transform. Coupled vibrations of the pulley-belt system are investigated via the Galerkin truncation. The natural frequencies of the coupled vibrations are obtained by using the fast Fourier transform. Moreover, frequency-response curves are abstracted from time histories. Therefore, resonance areas of the belt spans, the driven pulley and the accessory are presented. Furthermore, validity of the Galerkin method is examined by comparing with the differential and integral quadrature methods (DQM & IQM). By comparing the results with and without one-way device, significant damping effect of clutch on the dynamic response is discovered. Furthermore, the effects of the intensity of the driving pulley excitation and the inertia excitation are studied. Moreover, numerical results demonstrate that the two excitations interact on the steady

  11. The Development of the “One Belt and One Road” and Its Impacts on China-U.S. Relations

    Institute of Scientific and Technical Information of China (English)

    Xia; Liping

    2015-01-01

    In 2013,Chinese President Xi Jinping has taken the initiatives of promoting the"One Belt and One Road".The"One Belt"refers to the Silk Road Economic Belt,and"One Road"to the 21st Century Maritime Silk Road.The"One Belt and One Road"has become one important part of China’s strategy of domestic economic and social development,as well as one important part of China’s foreign strategy.

  12. Inner Radiation Belt Generation of Light Nuclei Isotope

    Science.gov (United States)

    Galper, A. M.; Koldashov, S. V.; Leonv, A. A.; Mikhailov, V. V.

    2003-07-01

    Nuclear interactions between inner zone protons and atoms in the upper atmosphere provide the essential source of H and He isotop es nuclei in radiation belt. This paper reports the calculations of these isotop es intensities from the inner zone proton intensity model AP-8, the atmosphere drift-averaged composition and densities model MSIS-90, and cross sections for the various interaction processes. To calculate drift-averaged densities and energy losses of secondaries the particles are traced in geomagnetic field according IGRF-95 model by numerical solution of motion equation. The calculations account for nuclear interactions kinematic along the whole trapped protons trajectories. The results of calculations are compared with experimental data from SAMPEX, CRRES, RESURS-04 and MITA satellites taken during different solar activity phases. The comparison with observational data shows that the atmosphere is sufficient source for inner zone 4 He, 3 He,2 H and 3 H for L-shell less than 1.3.

  13. A Tropical "NAT-like" belt observed from space

    CERN Document Server

    Chepfer, Hélène; 10.1029/2008GL036289

    2009-01-01

    The optical properties of cold tropical tropopause clouds are examined on a global scale, using two years of space-borne lidar observations from CALIPSO (June 2006 ? May 2008). The linear depolarization ratio, color ratio and backscatter signal are analyzed in tropical clouds colder than 200 K in a way similar to recent studies of Polar Stratospheric Clouds (PSCs). It is found that the three categories of particles encountered in PSC (Ice, Sulfate Ternary Solutions or STS, and Nitric Acid Trihydrate or NAT) do also occur in tropical cold cloud layers. Particles with optical properties similar to NAT are few, but they cover the tropical belt and represent about 20% of cold cloud tropical particles. The optical behavior of these particles requires them to be small, non-spherical, optically thin, and persistent in the TTL at temperatures colder than 200 K; NAT particles and very small ice crystals meet these criteria.

  14. Exploring the Jupiter's and Saturn's radiation belts with LOFAR

    Science.gov (United States)

    Girard, Julien N.; Zarka, Philippe; Pater Imke, de; Hess, Sebastien; Tasse, Cyril; Courtin, Regis; Hofstadter, Mark; Santos-Costa, Daniel; Nettelmann, Nadine; lorenzato, Lise

    2014-05-01

    Since its detection in the mid-fifties, the decimeter synchrotron radiation (DIM), originating from the radiation belts of Jupiter, has been extensively observed over a wide spectrum (from >300 MHz to 22 GHz) by various radio instruments (VLA, ATCA, WSRT, Cassini...). They provided accurate flux measurements as well as resolved maps of the emission that revealed spatial, temporal and spectral variabilities. The strong magnetic field (~4.2 G at the equator) is responsible for the radio emission generated by relativistic electrons. The emission varies at different time scales (short-time variations of hours to long-term variation over decades) due to the combination of visibility configuration (fast rotating 'dipole' magnetic field, beamed radio emission) and intrinsic local variations (interaction between relativistic electrons and satellites/dust, delayed effect of the solar wind ram pressure, impacts events) (e.g. de Pater & Klein, 1989; de Pater & Dunn, 2003; Bagenal (ed.) et al., 2004; Santos-Costa, 2009, 2011). A complete framework is necessary to fully understand the source, loss and transport processes of the electrons populating the inner magnetosphere over a wide frequency range. The low frequencies are associated with electron of lower energies situated in weaker magnetic field regions. LOFAR, the LOw Frequency ARray (LOFAR) (van Haarlem et al., 2012), the last generation of versatile and digital ground-based radio interferometer operates in the [30-250] MHz bandwidth. It brings very high time (~μsec), frequency (~kHz) and angular (~asec) resolutions and huge sensitivities (~mJy). In November 2011, a single 10-hour track enabled to cover an entire planetary rotation and led to image, for the first time, the radiation belts between 127-172 MHz (Girard et al. 2012, 2013). In Feb 2013, an 11-hour joint LOFAR/WSRT observing campaign seized the dyname state of the radiation belts from 45 MHz up to 5 GHz. We will present the current study of the radiation belts

  15. On the oldest asteroid families in the main belt

    CERN Document Server

    Carruba, V; Aljbaae, S; Domingos, R C; Huaman, M

    2016-01-01

    Asteroid families are groups of minor bodies produced by high-velocity collisions. After the initial dispersions of the parent bodies fragments, their orbits evolve because of several gravitational and non-gravitational effects,such as diffusion in mean-motion resonances, Yarkovsky and YORP effects, close encounters of collisions, etc. The subsequent dynamical evolution of asteroid family members may cause some of the original fragments to travel beyond the conventional limits of the asteroid family. Eventually, the whole family will dynamically disperse and no longer be recognizable. A natural question that may arise concerns the timescales for dispersion of large families. In particular, what is the oldest still recognizable family in the main belt? Are there any families that may date from the late stages of the Late Heavy Bombardment and that could provide clues on our understanding of the primitive Solar System? In this work, we investigate the dynamical stability of seven of the allegedly oldest familie...

  16. Why style matters - uncertainty and structural interpretation in thrust belts.

    Science.gov (United States)

    Butler, Rob; Bond, Clare; Watkins, Hannah

    2016-04-01

    Structural complexity together with challenging seismic imaging make for significant uncertainty in developing geometric interpretations of fold and thrust belts. Here we examine these issues and develop more realistic approaches to building interpretations. At all scales, the best tests of the internal consistency of individual interpretations come from structural restoration (section balancing), provided allowance is made for heterogeneity in stratigraphy and strain. However, many existing balancing approaches give misleading perceptions of interpretational risk - both on the scale of individual fold-thrust (trap) structures and in regional cross-sections. At the trap-scale, idealised models are widely cited - fault-bend-fold, fault-propagation folding and trishear. These make entirely arbitrary choices for fault localisation and layer-by-layer deformation: precise relationships between faults and fold geometry are generally invalidated by real-world conditions of stratigraphic variation and distributed strain. Furthermore, subsurface predictions made using these idealisations for hydrocarbon exploration commonly fail the test of drilling. Rarely acknowledged, the geometric reliability of seismic images depends on the assigned seismic velocity model, which in turn relies on geological interpretation. Thus iterative approaches are required between geology and geophysics. The portfolio of commonly cited outcrop analogues is strongly biased to examples that simply conform to idealised models - apparently abnormal structures are rarely described - or even photographed! Insight can come from gravity-driven deep-water fold-belts where part of the spectrum of fold-thrust complexity is resolved through seismic imaging. This imagery shows deformation complexity in fold forelimbs and backlimbs. However, the applicability of these, weakly lithified systems to well-lithified successions (e.g. carbonates) of many foreland thrust belts remains conjectural. Examples of

  17. Qinling Orogenic Belt: Its Palaeozoic- Mesozoic Evolution and Metallogenesis

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The formation, development and evolution of the Qinling orogenic belt can be divided into three stages: (1) formation and development of Precambrian basement in the Late Archaean- Palaeoproterozoic (3.0- 1.6 Ga), (2) plate evolution (0.8- 0.2 Ga), and (3) intracontinental orogeny and tectonic evolution in the Mesozoic. The Devonian (D) and Triassic (T) were the key transition period of the tectonic evolution of the Qinling orogenic belt. That is to say, in the Devonian, the Qinling micro-plate was separated from the northern margin of the Yangtze plate (passive continental margin). This period witnessed transition of the micro-plate from the compressional to extensional state, and consequently three types of sedimentary basins were formed, namely, the rift hydrothermal basin in the micro-plate, restricted ocean basin in the south, and residual ocean basin resulting from collision on the northern margin. In the Triassic the Qinling area was turned into the intracontinental orogen.The Devonian and Triassic were the main periods of enrichment of large amounts of metals. In the Devonian, many sedex-type massive Pb-Zn- (Cu)-Ag deposits were formed in the hydrothermal basins. In the Triassic (Indosinian-Yanshanian movements), many sediment-hosted disseminated gold deposits and reworked sedimentary type Pb-Zn-Hg-Sb (Au) deposits were formed in the rift hydrothermal basins. Many ductile shear zone-related gold deposits were formed in the restricted ocean basins and residual ocean basins on the two sides of the Qinling micro-plate. The above-mentioned discussion indicates that metallogenesis is not only consistent with geological events, but also controlled by them.

  18. A Path Planning Method for Robotic Belt Surface Grinding

    Institute of Scientific and Technical Information of China (English)

    WANG Wei; YUN Chao

    2011-01-01

    The flexible contact and machining with wide strip are two prominent advantages for the robotic belt grinding system,which can be widely used to improve the surface quality and machining efficiency while finishing the workpieces with sculptured surfaces.There lacks research on grinding path planning with the constraint of curvature.With complicated contact between the contact wheel and the workpiece,the grinding paths for robot can be obtained by the theory of contact kinematics.The grinding process must satisfy the universal demands of the belt grinding technologies,and the most important thing is to make the contact wheel conform to the local geometrical features on the contact area.For the local surfaces with small curvature,the curve length between the neighboring cutting locations becomes longer to ensure processing efficiency.Otherwise,for the local areas with large curvature,the curve length becomes shorter to ensure machining accuracy.A series of planes are created to intersect with the target surface to be ground,and the corresponding sectional profile curves are obtained.For each curve,the curve length between the neighboring cutting points is optimized by inserting a cutter location at the local area with large curvatures.A method of generating the grinding paths including curve length spacing optimization is set up.The validity is completely approved by the off-line simulation,and during the grinding experiments with the method,the quality of surface is improved.The path planning method provides a theoretical support for the smooth and accuracy path of robotic surface grinding.

  19. Inward diffusion and loss of radiation belt protons

    Science.gov (United States)

    Selesnick, R. S.; Baker, D. N.; Jaynes, A. N.; Li, X.; Kanekal, S. G.; Hudson, M. K.; Kress, B. T.

    2016-03-01

    Radiation belt protons in the kinetic energy range 24 to 76 MeV are being measured by the Relativistic Electron Proton Telescope on each of the two Van Allen Probes. Data have been processed for the purpose of studying variability in the trapped proton intensity during October 2013 to August 2015. For the lower energies (≲32 MeV), equatorial proton intensity near L = 2 showed a steady increase that is consistent with inward diffusion of trapped solar protons, as shown by positive radial gradients in phase space density at fixed values of the first two adiabatic invariants. It is postulated that these protons were trapped with enhanced efficiency during the 7 March 2012 solar proton event. A model that includes radial diffusion, along with known trapped proton source and loss processes, shows that the observed average rate of increase near L = 2 is predicted by the same model diffusion coefficient that is required to form the entire proton radiation belt, down to low L, over an extended (˜103 year) interval. A slower intensity decrease for lower energies near L = 1.5 may also be caused by inward diffusion, though it is faster than predicted by the model. Higher-energy (≳40 MeV) protons near the L = 1.5 intensity maximum are from cosmic ray albedo neutron decay. Their observed intensity is lower than expected by a factor ˜2, but the discrepancy is resolved by adding an unspecified loss process to the model with a mean lifetime ˜120 years.

  20. Two kinds of silicalites in Mount Ailao belt, Yunnan Province

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Two kinds of radiolarian silicalites at the bottom and top of the ophiolite in the Mount (Mt.) Ailao belt, Yunnan Province, are dealt with in this work in terms of geology, micro-paleontology, isotope and REE. The first kind of silicalite was defined as the turbidite formation. In this category, the radiolarian species lived in the Late Devonian (D3). The corresponding ecologic assemblage, composed of δ 30Si (0.4‰-0.5‰, average 0.03‰), δ Ce (0.77- 0.97, average 0.85) and LaN /YbN (0.77-1.06, average 0.96) of silicalite, shows that it occurred in the abyssal environment. The second kind of silicalite was defined as the mud-siliceous formation. Contacting conformably with the basalt of the ophiolite suit, the radiolarian silicalite at the top of ophiolite was in the category of the component units of the ophiolite in the Mt. Ailao belt. In this category, the radiolarian species lived in the Early Carboniferous (C1-). The corresponding ecologic assemblage, composed of d 30Si (0.2‰-1.3‰, averaging 0.7‰), dδCe (0.88- 0.92, averaging 0.90) and LaN /YbN (0.77-1.45, averaging 1.22), of silicalites indicate that it occurred in the bathyal environment. All these facts domonstrate that the Mt. Ailao must have been a small ocean basin at that time.

  1. Environmental benefits of enclosed conveying

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, K.

    1995-08-01

    Increasingly stringent legislation on operating controls in the bulk industry and increased environmental awareness has helped promote the role of enclosed conveying systems for solids handling. The article details developments in the field, emphasizing environmental benefits of the various enclosed conveying systems currently on the market. It is divided into sections on: pipe conveyors (from Bridgestone, Sicon, Imperial Technologies, Conveytech, PWM Anlagen and System, Mitsubishi Nagasaki Machinery Company, MAN Takraf, MVT Bernard Blatton and Huwood); en masse conveyors (from Redler and Scren Conveyor Corporation); and high angle conveyors (from Continental Conveyor). Specialist conveyors for Aerobelt Conveyors and Cavier are descried, which in addition to using some form of cladding to provide enclosure, include an air supported conveyor system or one where side rollers are replaced by a UHMW or stainless steel wing support for the conveyor belting provide a dust free system. A table lists details of sale of Continental Conveyor and Equipment Company high angle conveyors. 1 fig., 1 tab., 9 photos.

  2. First ultraviolet reflectance measurements of several Kuiper Belt objects, Kuiper Belt object satellites, and new ultraviolet measurements of A Centaur

    Energy Technology Data Exchange (ETDEWEB)

    Stern, S. A.; Schindhelm, E. [Southwest Research Institute, 1050 Walnut Street, Boulder, CO 80302 (United States); Cunningham, N. J., E-mail: astern@swri.edu [Nebraska Wesleyan University, 5000 Saint Paul Avenue, Lincoln, NE 68504 (United States)

    2014-05-01

    We observed the 2600-3200 Å (hereafter, mid-UV) reflectance of two Kuiper Belt Objects (KBOs), two KBO satellites, and a Centaur, using the Hubble Space Telescope (HST) Cosmic Origins Spectrograph (COS). Other than measurements of the Pluto system, these constitute the first UV measurements obtained of KBOs, and KBO satellites, and new HST UV measurements of the Centaur 2060 Chiron. We find significant differences among these objects, constrain the sizes and densities of Haumea's satellites, and report the detection of a possible spectral absorption band in Haumea's spectrum near 3050 Å. Comparisons of these objects to previously published UV reflectance measurements of Pluto and Charon are also made here.

  3. Explaining the dynamics of the ultra-relativistic third Van Allen radiation belt

    Science.gov (United States)

    Mann, I. R.; Ozeke, L. G.; Murphy, K. R.; Claudepierre, S. G.; Turner, D. L.; Baker, D. N.; Rae, I. J.; Kale, A.; Milling, D. K.; Boyd, A. J.; Spence, H. E.; Reeves, G. D.; Singer, H. J.; Dimitrakoudis, S.; Daglis, I. A.; Honary, F.

    2016-10-01

    Since the discovery of the Van Allen radiation belts over 50 years ago, an explanation for their complete dynamics has remained elusive. Especially challenging is understanding the recently discovered ultra-relativistic third electron radiation belt. Current theory asserts that loss in the heart of the outer belt, essential to the formation of the third belt, must be controlled by high-frequency plasma wave-particle scattering into the atmosphere, via whistler mode chorus, plasmaspheric hiss, or electromagnetic ion cyclotron waves. However, this has failed to accurately reproduce the third belt. Using a data-driven, time-dependent specification of ultra-low-frequency (ULF) waves we show for the first time how the third radiation belt is established as a simple, elegant consequence of storm-time extremely fast outward ULF wave transport. High-frequency wave-particle scattering loss into the atmosphere is not needed in this case. When rapid ULF wave transport coupled to a dynamic boundary is accurately specified, the sensitive dynamics controlling the enigmatic ultra-relativistic third radiation belt are naturally explained.

  4. Seat belt syndrome: Delayed or missed intestinal injuries, a case report and review of literature

    Science.gov (United States)

    Al-Ozaibi, Labib; Adnan, Judy; Hassan, Batool; Al-Mazroui, Alya; Al-Badri, Faisal

    2016-01-01

    Introduction Seat belt injuries are not uncommon. The use of seat belts is associated with a unique injury profile collectively termed “the seat belt syndrome”. The aim is to aid in the early diagnosis of seat belt injuries. Case presentation Two different patients presented to the emergency after sustaining a motor vehicle accident. Both were the drivers, restrained and had a frontal impact. On presentation they were hemodynamically stable with mild tenderness on the abdomen and the abdominal computed tomography (CT) did not show any signs of bowel or mesenteric injuries. The signs of peritonitis became obvious after 24 h in one case and after 3 days in the other. Discussion Early diagnosis provides better outcomes for patients with seat belt injuries, but this remains a challenge to trauma surgeons. The typical findings of peritonitis might not be present initially. The presence of abdominal wall ecchymosis (seat belt sign) increases the chance of intraabdominal injuries by eight folds. Conclusion Clinical signs of intestinal injuries might not be obvious on presentation. In the presence of seat belt sign the possibility of bowl injury must be suspected. Admit the patient for observation even if no clinical or radiological findings are present at presentation. PMID:26826929

  5. Metamorphism and plutonism in the Quetico Belt, Superior Province, N.W. Ontario

    Science.gov (United States)

    Percival, J. A.

    1986-01-01

    The Quetico Belt lies between the metavolcanic Wawa-Shebandowan and Wabigoon Belts. It consists of marginal metasedimentary rocks and central pelitic, gneissic and plutonic rocks. Metamorphism is Barrovian, at depths less than 10 km, and grade increases from margins to core of the belt: the outermost pelites are at chlorite-muscovite grade; inward a garnet-andalusite zone formed throughout the inner margin; and the central zone ranges form garnet-andalusite in the west and garnet-sillimanite-muscovite to garnet-sillimanite-cordierite and rare kyanite 6 to 150 km to the east. This increase is correlated with granitic intrusives. Migmatites in the core have intrusive leucosomes in the west and locally derived ones in the east. Isograd surfaces are steep where the belt is narrow and dip gently where it is wide. The Quetico Park intrusive complex of the central region of the Quetico Belt shows a zonation across it 20 to 50 km width from older, medium grained biotite composition to younger, coarse to pegmatitic granitic composition. Sediment of the Quetico basin had its source in the bordering metavolcanic belts and was deposited ca. 2.75 to 2.70 Ga ago. Boundaries of the belt dip inward, so it essentially is a graben of inter-arc or back-arc type.

  6. 切碎玉米秸秆螺旋输送性能试验研究%Performance Experiment of Screw Conveyor for Chopped Corn Stalks

    Institute of Scientific and Technical Information of China (English)

    赵圆圆; 王春光; 乌兰图雅; 王金莲

    2015-01-01

    This paper studied the single factor test and the orthogonal test of the screw conveyor performance of chopped corn stalks in the horizontal screw conveyor test device .The experiment studied the influence to the productivity and power consumption on the screw shaft speed , filling coefficient and pitch .The single factor test showed that the screw shaft speed , filling coefficient and pitch influenced the productivity and power consumption significantly ;and with the in-crease of screw shaft speed , the increase of filling coefficient and the increase of pitch , the productivity and power con-sumption are on the rise .The orthogonal test showed that these three factors impact on the productivity of the primary and secondary order is pitch , filling coefficient , screw shaft speed;these three factors impact on the power consumption of the primary and secondary order is screw shaft speed;pitch , filling coefficient .By the integrated balance method , the opti-mal level combination to maximize the productivity is A 1 B1 C3 , namely screw shaft speed 56 r/min, filling coefficient of 0.3, the pitch of 300 mm.This experiment can provide reference to improve the overall quality of the corn stalks spiral conveying .%在水平螺旋输送试验装置上对切碎玉米秸秆的螺旋输送性能进行了单因素试验和正交试验,研究了螺旋轴转速、填充系数和螺距对输送量和功率消耗的影响。单因素试验结果表明:螺旋轴转速、填充系数和螺距对输送量和功率消耗的影响显著;且随着螺旋轴转速、填充系数和螺距的增大,输送量和功率消耗都呈上升趋势。正交试验结果表明:因素对输送量影响的主次顺序是螺距、填充系数、转速;因素对功率消耗影响的主次顺序是转速、螺距、填充系数。采用综合平衡法最终得到的较优水平组合是 A1 B1 C3,即螺旋轴转速56 r/min、填充系数0.3、螺距300 mm。本试验可为提高玉米

  7. The Relative Deep Penetrations of Energetic Electrons and Ions into the Slot Region and Inner Belt

    Science.gov (United States)

    Zhao, H.; Li, X.; Claudepierre, S. G.; Fennell, J. F.; Blake, J. B.; Larsen, B.; Skoug, R. M.; Funsten, H. O.; Baker, D. N.; Reeves, G. D.; Spence, H. E.

    2015-12-01

    Energetic electrons in the inner magnetosphere are distributed into two regions: the inner radiation belt and the outer radiation belt, with the slot region in between separating the two belts. Though many studies have focused on the outer belt dynamics, the energetic electrons in the slot region and especially inner belt did not receive much attention until recently. A number of new features regarding electrons in the low L region have been reported lately, including the abundance of 10s-100s of keV electrons in the inner belt, the frequent deep injections of 100s of keV electrons, and 90°-minimum pitch angle distributions of 100s of keV electrons in the inner belt and slot region. In this presentation, we focus on the relative deep injections into the slot region and inner belt of energetic electrons and ions using observations from HOPE and MagEIS instruments on the Van Allen Probes. It is shown that while 10s - 100s of keV electrons penetrate commonly deep into the low L region and are persistent in the inner belt, the deep injections of ions with similar energies occur rarely, possibly due to the fast loss of ions in the low L region. The energy spectra and pitch angle distributions of electrons and ions during injections are also very different, indicating the existence of different physical mechanisms acting on them. In addition, some intriguing similarities between lower energy ions and higher energy electrons will also be discussed.

  8. A method for automated control of belt velocity changes with an instrumented treadmill.

    Science.gov (United States)

    Hinkel-Lipsker, Jacob W; Hahn, Michael E

    2016-01-01

    Increased practice difficulty during asymmetrical split-belt treadmill rehabilitation has been shown to improve gait outcomes during retention and transfer tests. However, research in this area has been limited by manual treadmill operation. In the case of variable practice, which requires stride-by-stride changes to treadmill belt velocities, the treadmill control must be automated. This paper presents a method for automation of asymmetrical split-belt treadmill walking, and evaluates how well this method performs with regards to timing of gait events. One participant walked asymmetrically for 100 strides, where the non-dominant limb was driven at their self-selected walking speed, while the other limb was driven randomly on a stride-by-stride basis. In the control loop, the key factors to insure that the treadmill belt had accelerated to its new velocity safely during the swing phase were the sampling rate of the A/D converter, processing time within the controller software, and acceleration of the treadmill belt. The combination of these three factors resulted in a total control loop time during each swing phase that satisfied these requirements with a factor of safety that was greater than 4. Further, a polynomial fit indicated that belt acceleration was the largest contributor to changes in this total time. This approach appears to be safe and reliable for stride-by-stride adjustment of treadmill belt speed, making it suitable for future asymmetrical split-belt walking studies. Further, it can be incorporated into virtual reality rehabilitation paradigms that utilize split-belt treadmill walking. PMID:26654110

  9. Pb Isotope Mapping in the Tongbai-Dabie Orogenic Belt, Central China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Li; ZHONG Zengqiu; WANG Linsen; Zhang Benren

    2008-01-01

    Tongbai-Dabie orogenic belt in Central China is a part of the collisional belt between the Yangtze and North China cratons. It represents one of the most extensive ultrahigh-pressure (UHP) and high-pressure (HP) metamorphic rocks in the world. The Pb isotope mapping in this area is a significant method to constrain the crustal structure and tectonic evolution and to identify the tectonic boundaries within the vertical tectonic stack. Based on the Pb isotope compositions of the Dabie complex (DBC), the Tongbai complex (TBC), UHP and HP metamorphic rocks and associated foliated granites, the lower metamorphosed rocks from North Huaiyang (NHY) tectonic belt, and Cretaceous granites in the Tongbai-Dabie orogenic belt, we determined the Pb isotope geochemical map of the Tongbai-Dabie orogenic belt. The Pb isotope map shows that the Pb isotope compositions are similar within each geological body or lithotectonic unit, but the Pb isotope compositions of different lithotectonic units show systematic variations in the Tongbai-Dabie orogenic belt. The NHY tectonic belt contrasts strongly with the Tongbal-Dabie UHP-HP metamorphic belt in Pb isotope compositions.It is suggested that the line along the Xiaotian-Mozitan fault, the north limit of the Tongbai-Dabie UHP and HP metamorphic rocks, represents an important tectonic boundary. Within the Tongbai-Dabie HP -UHP metamorphic belt, to the south of Xiaotian-Mozitan fault, the vertical variations of Pb isotope compositions in different lithotectonic units and the spatial relationship among different major lithotectonic units have been constrained.

  10. Analysis on damage cause of belt eyes for bypass feedwater isolation valves of Daya Bay and Ling'ao NPPs

    International Nuclear Information System (INIS)

    When all of bypass feedwater isolation valves of Daya Bay and Ling'ao NPPs were inspected under disassembled condition, it was found that the belt eyes were damaged in various degrees. The analysis on macro appearance, chemical composition, metallographic, Scanning Electron Microscope and fluid mechanics simulation were carried out on the damaged belt eyes. The results show that the flow rate of belt eye is well above the manufacturer's recommendation so that flow accelerated corrosion and cavitation erosion occur on the belt eyes. According to the damage causes of the belt eyes, corresponding corrective actions are proposed. (authors)

  11. Avaliação técnica de um transportador pneumático de grãos por aspiração Technical evaluation of a suction pneumatic grain conveyor

    Directory of Open Access Journals (Sweden)

    Luís Antônio Bortolaia

    2008-04-01

    Full Text Available Este trabalho apresenta os resultados da avaliação técnica do protótipo do transportador pneumático de grãos por aspiração ASP 200. O equipamento foi construído para uso em instalações armazenadoras agrícolas, na limpeza de pés de elevadores, moegas e renovação do ar em galerias de silos. Os testes avaliaram características mecânicas do equipamento, descargas de material e ar, perdas de carga, vedação do equipamento, eficiência dos captores e o diâmetro das mangueiras. Os resultados subsidiaram diversas recomendações para melhoria no projeto do equipamento, que aumentarão a sua eficiência operacional. Embora o transporte pneumático seja considerado uma ciência experimental, os autores notaram a falta de procedimentos, parâmetros e orientações para testes e comparações na literatura, que são fundamentais para o desenvolvimento do projeto desses transportadores.This research shows the results that were obtained from technical evaluation of ASP 200 prototype that is a suction pneumatic grain conveyor. This equipment was built to use in agricultural storage facilities to clean bucket elevator feet, loading hoppers and air renovation in silo galleries. The tests have evaluated mechanical characteristics of conveyor, air and material discharges, pressure losses, air infiltration, intake nozzle efficiency and piping diameters. The results have allowed several recommendations to improve equipment design that will increase its operational efficiency. Although pneumatic conveying is considered an experimental science, the authors have perceived the lack of procedures, parameters and orientations to conduct tests and comparisons in literature, that are fundamental to develop a design of this conveyor type.

  12. Three Alkali—Rich Intrusive Rock Belts Bewly Discovered in the Mt.Kunlkun—Mt.Altun Region,Xinjiang,China

    Institute of Scientific and Technical Information of China (English)

    朱笑青; 王元龙; 等

    2002-01-01

    The newly discovered three alkali-rich intrusive rock belts in the Mt.Kunlun Mt.Altun region of southern Xinjiang are the Lapeiquan-Yitunbulak alkali-rich intrusive fock belt, the Gez-Taxkorgan alkali-rich intrusive rock belt and the Beeilisai-Abulash alkali-rich intrusive rock belt.The former two belts were formed during the Yanshanian period,and the third one was formed during the Himalayan period,which is the youngest alkali-rich intrusive rock belt in China.The discovery of the alkali-rich intrusive rock belts is of great significance in shedding light on the history of tectono-magmatic activities in this region.

  13. Three Alkali-Rich Intrusive Rock Belts Newly Discovered in the Mt. Kunlun-Mt. Altun Region, Xinjiang, China

    Institute of Scientific and Technical Information of China (English)

    朱笑青; 王元龙; 毕华; 王中刚

    2002-01-01

    The newly discovered three alkali-rich intrusive rock belts in the Mt. Kunlun Mt.Altun region of southern Xinjiang are the Lapeiquan-Yitunbulak alkali-rich intrusive rock belt,the Gez-Taxkorgan alkali-rich intrusive rock belt and the Beilisai-Abulash alkali-rich intrusive rock belt. The former two belts were formed during the Yanshanian period, and the third one was formed during the Himalayan period, which is the youngest alkali-rich intrusive rock belt in China. The discovery of the alkali-rich intrusive rock belts is of great significance in shedding light on the history of tectono-magmatic activities in this region.

  14. TERRAIN TECTONICS OF THE CENTRAL ASIAN FOLDED BELT

    Directory of Open Access Journals (Sweden)

    M. M. Buslov

    2015-09-01

    Full Text Available The terrain analysis concept envisages primarily a possibility of approximation of fragments / terrains of various geodynamic settings which belong to different plates. The terrain analysis can supplement the theory of plate tectonics in solving problems of geodynamics and tectonics of regions of the crust with complex structures. The Central Asian belt is among such complicated regions. Terrain structures occurred as a result of combined movements in the system of 'frontal' and/or oblique subduction – collision. In studies of geological objects, it is required first of all to prove their (vertical and horizontal autochthony in relations to each other and then proceed to paleogeodynamic, paleotectonic and paleogeographic reconstructions. Obviously, such a complex approach needs data to be obtained by a variety of research methods, including those applied to study geologic structures, stratigraphy, paleontology, paleogeography, lithothlogy, geochemistry, geochronology, paleomagnetism etc. Only by correlating such data collected from inter-disciplinary studies of the regions, it is possible to establish reliable characteristics of the geological settings and avoid mistakes and misinterpretations that may be associated with the 'stratigraphic' approach to solutions of both regional and global problems of geodynamics and tectonics of folded areas. The terrain analysis of the Central Asian folded belt suggests that its tectonic structure combines marginal continental rock complexes that were formed by the evolution of two major oceanic plates. One of them is the plate of the Paleo-Asian Ocean. As the analogue of the current Indo-Atlantic segment of Earth, it is characterised by the presence of continental blocks in the composition of the oceanic crust and the formation of oceanic basins resulting from the breakup of Rodinia and Gondvana. In the course of its evolution, super-continents disintegrated, and the blocks were reunited into the Kazakhstan

  15. New insights into main belt asteroid collisional lifetimes

    Science.gov (United States)

    Henych, Tomas; Holsapple, Keith

    2016-10-01

    We are developing a new Monte Carlo code to study the collisional and spin evolution of main belt asteroids. A byproduct is information on asteroid lifetimes. We find new interpretations and values of those lifetimes.In the conventional approach, the "collisional lifetime" is measured by the time when an asteroid is struck by an impactor large enough to remove one-half of the target's mass. That event is called a catastrophic disruption (CD). From an assumed population of impactors and Poisson statistics, one can estimate the largest expected impactor to impact in a given time interval to get its expected collisional lifetime. However, our Monte Carlo simulations give lifetimes that are distinctly shorter. That raises questions about the basic definition of catastrophic disruption.During its presence in the main belt, many other asteroids of all sizes continually strike a target asteroid. Before the CD one happens, there are many small impacts, and a few less than but not equal to the CD one. Each impact erodes the target asteroid. Very commonly, it is eroded to a much smaller mass before some CD event. We will present examples.So what shall we define as its collisional lifetime? Should it be the time for which its mass is reduced to one-half of its original mass, irrespective of how that happened, perhaps from many impacts? Or when any single impact reduces its mass to one-half of its original mass? Or when a single impact reduces it to one-half of its current mass?We propose that collisional lifetime is defined as the time at which it reaches 50% of its original mass, from any combination of small and/or large events. We use cratering and ejecta scaling formulas (e.g. Holsapple, 1993, Housen and Holsapple, 2011) to calculate the eroded mass history of the target for a history of impactors and calculate the outcome of any impact using the current size. In the gravity regime, the eroded body is easier to disrupt. We will present our lifetime estimates and those of

  16. The absolute magnitude distribution of Kuiper Belt objects

    Energy Technology Data Exchange (ETDEWEB)

    Fraser, Wesley C. [Herzberg Institute of Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Brown, Michael E. [Division of Geological and Planetary Sciences, California Institute of Technology, 1200 East California Boulevard, Pasadena, CA 91125 (United States); Morbidelli, Alessandro [Laboratoire Lagrange, UMR7293, Université de Nice Sophia-Antipolis, CNRS, Observatoire de la Côte d' Azur, BP 4229, F-06304 Nice (France); Parker, Alex [Department of Astronomy, University of California at Berkeley, Berkeley, CA 94720 (United States); Batygin, Konstantin, E-mail: wesley.fraser@nrc.ca [Institute for Theory and Computation, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, MS 51, Cambridge, MA 02138 (United States)

    2014-02-20

    Here we measure the absolute magnitude distributions (H-distribution) of the dynamically excited and quiescent (hot and cold) Kuiper Belt objects (KBOs), and test if they share the same H-distribution as the Jupiter Trojans. From a compilation of all useable ecliptic surveys, we find that the KBO H-distributions are well described by broken power laws. The cold population has a bright-end slope, α{sub 1}=1.5{sub −0.2}{sup +0.4}, and break magnitude, H{sub B}=6.9{sub −0.2}{sup +0.1} (r'-band). The hot population has a shallower bright-end slope of, α{sub 1}=0.87{sub −0.2}{sup +0.07}, and break magnitude H{sub B}=7.7{sub −0.5}{sup +1.0}. Both populations share similar faint-end slopes of α{sub 2} ∼ 0.2. We estimate the masses of the hot and cold populations are ∼0.01 and ∼3 × 10{sup –4} M {sub ⊕}. The broken power-law fit to the Trojan H-distribution has α{sub 1} = 1.0 ± 0.2, α{sub 2} = 0.36 ± 0.01, and H {sub B} = 8.3. The Kolmogorov-Smirnov test reveals that the probability that the Trojans and cold KBOs share the same parent H-distribution is less than 1 in 1000. When the bimodal albedo distribution of the hot objects is accounted for, there is no evidence that the H-distributions of the Trojans and hot KBOs differ. Our findings are in agreement with the predictions of the Nice model in terms of both mass and H-distribution of the hot and Trojan populations. Wide-field survey data suggest that the brightest few hot objects, with H{sub r{sup ′}}≲3, do not fall on the steep power-law slope of fainter hot objects. Under the standard hierarchical model of planetesimal formation, it is difficult to account for the similar break diameters of the hot and cold populations given the low mass of the cold belt.

  17. The Main Asteroid Belt: The Crossroads of the Solar System

    Science.gov (United States)

    Michel, Patrick

    2015-08-01

    Orbiting the Sun between Mars and Jupiter, main belt asteroids are leftover planetary building blocks that never accreted enough material to become planets. They are therefore keys to understanding how the Solar System formed and evolved. They may also provide clues to the origin of life, as similar bodies may have delivered organics and water to the early Earth.Strong associations between asteroids and meteorites emerged thanks to multi-technique observations, modeling, in situ and sample return analyses. Spacecraft images revolutionized our knowledge of these small worlds. Asteroids are stunning in their diversity in terms of physical properties. Their gravity varies by more orders of magnitude than its variation among the terrestrial planets, including the Moon. Each rendezvous with an asteroid thus turned our geological understanding on its head as each asteroid is affected in different ways by a variety of processes such as landslides, faulting, and impact cratering. Composition also varies, from ice-rich to lunar-like to chondritic.Nearly every asteroid we see today, whether of primitive or evolved compositions, is the product of a complex history involving accretion and one or more episodes of catastrophic disruption that sometimes resulted in families of smaller asteroids that have distinct and indicative petrogenic relationships. These families provide the best data to study the impact disruption process at scales far larger than those accessible in laboratory. Tens, perhaps hundreds, of early asteroids grew large enough to thermally differentiate. Their traces are scattered pieces of their metal-rich cores and, more rarely, their mantles and crusts.Asteroids represent stages on the rocky road to planet formation. They have great stories to tell about the formation and evolution of our Solar System as well as other planetary systems: asteroid belts seem common around Sun-like stars. We will review our current knowledge on their properties, their link to

  18. Improved electroacoustic dewatering (EAD) belt press for food products. Phase 3, Technical progress report

    Energy Technology Data Exchange (ETDEWEB)

    1994-02-01

    Battelle`s electroacoustic dewatering (EAD) process improves the performance of mechanical dewatering processes for several food products (such as corn fiber) by superimposing electric and ultrasonic fields. EAD has the potential to save 0.027 to 0.035 quad/yr energy by 1995 in the food processing industry, which consumed 0.15 to 0.18 quad in 1986. This report covers Phase III for demonstrating the EAD prototype on corn wet milling products (corn fiber and gluten); only Task 1 (prototype preparation and planning) was completed. EAD performance was examined in the laboratory; availability of a test site was examined. The single-roll, postdewatering EAD belt press prototype can accept material predewatered by a screw press, centrifuge, or any other mechanical dewatering device. The two-belt system, utilizing a copper-polymer cathode belt, performed as well as the three-belt system used in Phase II.

  19. Percentage of Drivers and Front Seat Passengers Wearing Seat Belts, 2012, Region 9 - San Francisco

    Data.gov (United States)

    U.S. Department of Health & Human Services — Source for national data: National Occupant Protection Use Survey (NOPUS), 2012. Source for state data: State Observational Survey of Seat Belt Use, 2012.

  20. CRED REA Fish Team Belt Transect Survey at Kauai, Main Hawaiian Islands, 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 7 sites at Kauai in the Main...

  1. CRED REA Fish Team Belt Transect Survey at Ofu-Olosega, American Samoa, 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 12 sites at Ofu-Olosega in the...

  2. CRED REA Fish Team Belt Transect Surveys at Maro Reef, 2002

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 5 sites at Maro Reef in October,...

  3. CRED REA Fish Team Belt Transect Surveys at Pearl and Hermes Reef, 2002

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 17 sites at Pearl Hermes Reef in...

  4. CRED REA Fish Team Belt Transect Surveys at Laysan Island, 2002

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 3 sites at Laysan Island in...

  5. CRED REA Fish Team Belt Transect Surveys at French frigate Shoals, 2002

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 12 sites at French Frigate Shoals...

  6. CRED REA Fish Team Belt Transect Surveys at the Midway Atoll, 2002

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 12 sites at Midway Atoll in...

  7. Principal Resonance of Parametrically Excited Moving Viscoelastic Belts with Geometrical Nonlinearity

    Institute of Scientific and Technical Information of China (English)

    侯之超; 祖武争

    2004-01-01

    Nonlinear dynamic analysis is performed on moving belts subjected to geometric nonlinearity and initial tension fluctuation.To incorporate more accurately the damping mechanism of belt material, linear viscoelastic models are adopted in a unified form of differential operators.To circumvent high-order differential vibration equation of time-varying coefficients and with gyroscopic and nonlinear terms, where analytical solution is almost impossible, a systematic approach is presented by reforming the motion equation and directly using the method of multiple scales.To exemplify the procedure, the solutions at principal resonance are obtained and their stability conditions are derived for employing a Kelvin-Voigt model to reflect the property of the belt material.The solutions and stability conditions successfully reduce to those for using Kelvin model and elastic model, which validate the present approaches.Numerical simulations highlight the effects of tension fluctuations and translating speeds on the stability of the belt vibration.

  8. Wave-induced loss of ultra-relativistic electrons in the Van Allen radiation belts

    Science.gov (United States)

    Shprits, Yuri Y.; Drozdov, Alexander Y.; Spasojevic, Maria; Kellerman, Adam C.; Usanova, Maria E.; Engebretson, Mark J.; Agapitov, Oleksiy V.; Zhelavskaya, Irina S.; Raita, Tero J.; Spence, Harlan E.; Baker, Daniel N.; Zhu, Hui; Aseev, Nikita A.

    2016-01-01

    The dipole configuration of the Earth's magnetic field allows for the trapping of highly energetic particles, which form the radiation belts. Although significant advances have been made in understanding the acceleration mechanisms in the radiation belts, the loss processes remain poorly understood. Unique observations on 17 January 2013 provide detailed information throughout the belts on the energy spectrum and pitch angle (angle between the velocity of a particle and the magnetic field) distribution of electrons up to ultra-relativistic energies. Here we show that although relativistic electrons are enhanced, ultra-relativistic electrons become depleted and distributions of particles show very clear telltale signatures of electromagnetic ion cyclotron wave-induced loss. Comparisons between observations and modelling of the evolution of the electron flux and pitch angle show that electromagnetic ion cyclotron waves provide the dominant loss mechanism at ultra-relativistic energies and produce a profound dropout of the ultra-relativistic radiation belt fluxes. PMID:27678050

  9. CRED REA Fish Team Belt Transect Surveys at Johnston Island, 2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 12 sites at Johnston Island in...

  10. Rapid flattening of butterfly pitch angle distributions of radiation belt electrons by whistler-mode chorus

    Science.gov (United States)

    Yang, Chang; Su, Zhenpeng; Xiao, Fuliang; Zheng, Huinan; Wang, Yuming; Wang, Shui; Spence, H. E.; Reeves, G. D.; Baker, D. N.; Blake, J. B.; Funsten, H. O.

    2016-08-01

    Van Allen radiation belt electrons exhibit complex dynamics during geomagnetically active periods. Investigation of electron pitch angle distributions (PADs) can provide important information on the dominant physical mechanisms controlling radiation belt behaviors. Here we report a storm time radiation belt event where energetic electron PADs changed from butterfly distributions to normal or flattop distributions within several hours. Van Allen Probes observations showed that the flattening of butterfly PADs was closely related to the occurrence of whistler-mode chorus waves. Two-dimensional quasi-linear STEERB simulations demonstrate that the observed chorus can resonantly accelerate the near-equatorially trapped electrons and rapidly flatten the corresponding electron butterfly PADs. These results provide a new insight on how chorus waves affect the dynamic evolution of radiation belt electrons.

  11. CRED REA Fish Team Belt Transect Survey at Santa Rosa Bank, Marianas Archipelago, 2005

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 2 sites at Santa Rosa Bank in the...

  12. CRED REA Fish Team Belt Transect Survey at Santa Rosa Reef, 2003

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 2 sites at Santa Rosa Reef in the...

  13. CRED REA Fish Team Belt Transect Surveys at Midway Atoll, 2003

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 9 sites at Midway Atoll in July,...

  14. CRED REA Fish Team Belt Transect Survey at Rose, American Samoa, 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 12 sites at Rose in the American...

  15. Sm-Nd dating of Fig Tree clay minerals of the Barberton greenstone belt, South Africa

    Science.gov (United States)

    Toulkeridis, T.; Goldstein, S. L.; Clauer, N.; Kroner, A.; Lowe, D. R.

    1994-01-01

    Sm-Nd isotopic data from carbonate-derived clay minerals of the 3.22-3.25 Ga Fig Tree Group, Barberton greenstone belt, South Africa, form a linear array corresponding to an age of 3102 +/- 64 Ma, making these minerals the oldest dated clays on Earth. The obtained age is 120-160 m.y. younger than the depositional age determined by zircon geochronology. Nd model ages for the clays range from approximately 3.39 to 3.44 Ga and almost cover the age variation of the Barberton greenstone belt rocks, consistent with independent evidence that the clay minerals are derived from material of the belt. The combined isotopic and mineralogical data provide evidence for a cryptic thermal overprint in the sediments of the belt. However, the highest temperature reached by the samples since the time of clay-mineral formation was <300 degrees C, lower than virtually any known early Archean supracrustal sequence.

  16. Motivating signage prompts safety belt use among drivers exiting senior communities.

    Science.gov (United States)

    Cox, B S; Cox, A B; Cox, D J

    2000-01-01

    Senior drivers are vulnerable to automobile crashes and subsequent injury and death. Safety belts reduce health risks associated with auto crashes. Therefore, it is important to encourage senior drivers to wear safety belts while driving. Using an AB design, replicated five times, we evaluated the short- and long-term effects of a sign with the message "BUCKLE UP, STAY SAFE" attached to a stop sign at the exits of five different senior communities. Safety belt use was stable during two pretreatment assessments averaged across the five sites and 250 drivers (72% and 68% usage), but significantly increased following installation of these signs (94% usage). Six months after installation of the signs, the effect persisted (88% usage). Use of such signs may be a cost-effective way of promoting safety belt use.

  17. CRED REA Fish Team Belt Transect Survey at Midway, NW Hawaiian Islands, 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 9 sites at Midway in the NW...

  18. Watershed regressions for pesticides (WARP) for predicting atrazine concentration in Corn Belt streams

    Science.gov (United States)

    Stone, Wesley W.; Gilliom, Robert J.

    2011-01-01

    Watershed Regressions for Pesticides (WARP) models, previously developed for atrazine at the national scale, can be improved for application to the U.S. Corn Belt region by developing region-specific models that include important watershed characteristics that are influential in predicting atrazine concentration statistics within the Corn Belt. WARP models for the Corn Belt (WARP-CB) were developed for predicting annual maximum moving-average (14-, 21-, 30-, 60-, and 90-day durations) and annual 95th-percentile atrazine concentrations in streams of the Corn Belt region. All streams used in development of WARP-CB models drain watersheds with atrazine use intensity greater than 17 kilograms per square kilometer (kg/km2). The WARP-CB models accounted for 53 to 62 percent of the variability in the various concentration statistics among the model-development sites.

  19. The WISE Survey of the Albedo Distribution of Main Belt Asteroids

    NARCIS (Netherlands)

    Masiero, J.; Mainzer, A.; Grav, T.; Delbó, M.; Mueller, M.; WISE Team, [No Value

    2010-01-01

    Using date from the Wide-field Infrared Survey Explorer (WISE) we investigate the albedo distribution across the main belt of asteroids. When complete WISE will measure albedos and diameters for ~100,000 asteroids.

  20. The Contraction/Expansion History of Charon with implication for its Planetary Scale Tectonic Belt

    CERN Document Server

    Malamud, Uri; Schubert, Gerald

    2016-01-01

    The New-Horizons mission to the Kuiper Belt has recently revealed intriguing features on the surface of Charon, including a network of chasmata, cutting across or around a series of high topography features, conjoining to form a belt. It is proposed that this tectonic belt is a consequence of contraction/expansion episodes in the moon's evolution associated particularly with compaction, differentiation and geophysical reactions of the interior. The proposed scenario involves no need for solidification of a vast subsurface ocean and/or a warm initial state. This scenario is based on a new, detailed thermo-physical evolution model of Charon that includes multiple processes. According to the model, Charon experiences two contraction/expansion episodes in its history that may provide the proper environment for the formation of the tectonic belt. This outcome remains qualitatively the same even if we assume a different initial composition and mass. Two alternative explanations for the precise localization and orie...

  1. CRED REA Fish Team Belt Transect Survey at Pathfinder Reef, Marianas Archipelago, 2005

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 2 sites at Pathfinder Reef in the...

  2. CRED REA Fish Team Belt Transect Survey at Baker, Pacific Remote Island Areas in 2008

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 4 sites at Baker in the Pacific...

  3. CRED REA Fish Team Belt Transect Survey at Ta'u, 2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 9 sites at Ta'u Islands in...

  4. Poleward expansion of the tropical belt derived from upper tropospheric water vapour

    OpenAIRE

    You, Qinglong; Min, Jinzhong; Kang, Shichang; Pepin, Nick

    2015-01-01

    Based on intersatellite-calibrated high-resolution infrared radiation sounder (HIRS) upper tropospheric water vapour (UTWV) brightness temperatures, the width of the tropical belt is defined as the distance between the latitudes at which maximum HIRS UTWV brightness temperatures are recorded in both hemispheres. Poleward expansion of the tropical belt is evident during 1979–2013 on an annual basis, with an average global magnitude of 1.57° latitude per decade. Most rapid widening is evident i...

  5. EFFECTS OF BELT SPEED, PRESSURE AND GRIT SIZE ON THE SANDING OF Pinus elliottii WOOD

    OpenAIRE

    Manoel Cléber de Sampaio Alves; Luiz Fernando Frezzatti Santiago; Marcos Tadeu Tiburcio Gonçalves; Ivaldo De Domênico Valarelli; Francisco Mateus Faria de Almeida Varasquim

    2015-01-01

    The present paper aims to evaluate the influence of the factors (belt speed, pressure and grit size) on the output parameters (temperature and surface roughness) for Pinus elliottii wood sanding, processed parallel to the fibers. Three levels of belt speed, three levels of pressure and four levels of grit size were employed, with six replicates for each process, totaling 216 observations. The experiment conducted under a randomized complete block design (RCBD). The results were...

  6. Organochlorine and organophosphorus pesticide residues in fodder and milk samples along Musi river belt, India

    OpenAIRE

    Korrapati Kotinagu; Nelapati Krishnaiah

    2015-01-01

    Aim: The present study was conducted to find the organochlorine pesticide (OCP) and organophosphorus pesticide (OPP) residues in fodder and milk samples along Musi river belt, India. Materials and Methods: Fodder and milk samples collected from the six zones of Musi river belt, Hyderabad India were analyzed by gas chromatography with electron capture detector for OCP residues and pulsated flame photometric detector for the presence of OPP residues. Results: The gas chromatographic analysis of...

  7. MEASURING RESULTS NUMERAL TREATMENT OF IMPULSIVE CURRENTS BY MEANS OF ROGOVSKY BELT APPLICATION

    Directory of Open Access Journals (Sweden)

    U. Batygin

    2009-01-01

    Full Text Available The technique of numerical processing of measurement results of pulse currents by means of Rogovsky belt application is offered in the given work. It is shown that at measurement of signals by digital oscillographs and further numerical transformation of target signals, the possibilities of Rogovsky belt without the application of additional devices that in turn allows to define parameters of pulse currents with any peak-time characteristics essentially expand.

  8. The New Horizons Pluto Kuiper belt Mission: An Overview with Historical Context

    OpenAIRE

    Stern, S. Alan

    2007-01-01

    NASA's New Horizons (NH) Pluto-Kuiper belt (PKB) mission was launched on 19 January 2006 on a Jupiter Gravity Assist (JGA) trajectory toward the Pluto system for a 14 July 2015 closest approach; Jupiter closest approach occurred on 28 February 2007. It was competitively selected by NASA for development on 29 November 2001. New Horizons is the first mission to the Pluto system and the Kuiper belt; and will complete the reconnaissance of the classical planets. The ~400 kg spacecraft carries sev...

  9. The Physiologic Responses of Dutch Belted Rabbits Infected with Inhalational Anthrax

    OpenAIRE

    Lawrence, William S.; Hardcastle, Jason M; Brining, Douglas L; Weaver, Lori E; Ponce, Cindy; Whorton, Elbert B.; Johnny W. Peterson

    2009-01-01

    Bacillus anthracis, the causative agent of anthrax, is a category A priority pathogen that causes extensive damage in humans. For this reason, B. anthracis has been the focus of numerous studies using various animal models. In this study, we explored physiologic parameters in Dutch belted rabbits with inhalation anthrax to characterize the disease progression in this model. To this end, we infected Dutch belted rabbits with 100 LD50 B. anthracis Ames spores by nasal instillation and continuou...

  10. Measurement and monitoring of electrocardiogram belt tension in premature infants for assessment of respiratory function

    Directory of Open Access Journals (Sweden)

    Hegyi Thomas

    2007-04-01

    Full Text Available Abstract Background Monitoring of the electrocardiogram (ECG in premature infants with conventional adhesive-backed electrodes can harm their sensitive skin. Use of an electrode belt prevents skin irritation, but the effect of belt pressure on respiratory function is unknown. A strain gauge sensor is described which measures applied belt tension. Method The device frame was comprised of an aluminum housing and slide to minimize the device weight. Velcro tabs connected housing and slide to opposite tabs located at the electrode belt ends. The slide was connected to a leaf spring, to which were bonded two piezoresistive transducers in a half-bridge circuit configuration. The device was tested for linearity and calibrated. The effect on infant respiratory function of constant belt tension in the normal range (30 g–90 g was determined. Results The mechanical response to a step input was second order (fn = 401 Hz, ζ = 0.08. The relationship between applied tension and output voltage was linear in the range 25–225 gm of applied tension (r2 = 0.99. Measured device sensitivity was 2.18 mV/gm tension using a 5 V bridge excitation voltage. When belt tension was increased in the normal range from 30 gm to 90 gm, there was no significant change in heart rate and most respiratory functions during monitoring. At an intermediate level of tension of 50 gm, pulmonary resistance and work of breathing significantly decreased. Conclusion The mechanical and electrical design of a device for monitoring electrocardiogram electrode belt tension is described. Within the typical range of application tension, cardiovascular and respiratory function are not substantially negatively affected by electrode belt force.

  11. Community food environment measures in the Alabama Black Belt: Implications for cancer risk reduction

    OpenAIRE

    Rebecca Gyawu; Quansah, Joseph E.; Souleymane Fall; Gichuhi, Peter N; Bovell-Benjamin, Adelia C

    2015-01-01

    In-store measures were utilized to evaluate the availability of healthy food choices and nutrition/health promotion messages for cancer risk reduction in the selected Alabama Black Belt counties/cities. Sixty one retail food outlets (RFOs) were audited in 12 Alabama Black Belt cities. Store types included convenience stores (49.2%), restaurants (19.7%), fast food restaurants (16.4%), small supermarkets (8.2%), and large supermarket and farmers' markets (3.3 %), respectively. Although there we...

  12. Aeromagnetic and aeromagnetic-based geologic maps of the Coastal Belt, Franciscan Complex, northern California

    Science.gov (United States)

    Langenheim, V.E.; Jachens, R.C.; McLaughlin, R.J.

    2011-01-01

    The Coastal belt of the Franciscan Complex represents a Late Cretaceous to Miocene accretionary prism and overlying slope deposits. Its equivalents may extend from the offshore outer borderland of southern California to north of the Mendocino Triple Junction under the Eel River Basin and in the offshore of Cascadia. The Coastal belt is exposed on land in northern California, yet its structure and stratigraphy are incompletely known because of discontinuous exposure, structural disruption, and lithologically non-distinctive clastic rocks. The intent of this report is to make available, in map form, aeromagnetic data covering the Coastal belt that provide a new dataset to aid in mapping, understanding, and interpreting the incompletely understood geology and structure in northern California. The newly merged aeromagnetic data over the Coastal belt of the Franciscan Complex reveal long, linear anomalies that indicate remarkably coherent structure within a terrane where mapping at the surface indicates complex deformation and that has been described as "broken formation" and, even locally as "melange". The anomalies in the Coastal belt are primarily sourced by volcanic-rich graywackes and exotic blocks of basalt. Some anomalies along the contact of the Coastal belt with the Central belt are likely caused by local interleaving of components of the Coast Ranges ophiolite. These data can be used to map additional exotic blocks within the Coastal belt and to distinguish lithologically indistinct graywackes within the Coastal terrane. Using anomaly asymmetry allows projection of these "layers" into the subsurface. This analysis indicates predominant northeast dips consistent with tectonic interleaving of blocks within a subduction zone.

  13. Optimal linear filters for radiometric transport belt balances

    International Nuclear Information System (INIS)

    Due to a very short measuring path, dynamic measurement can be performed with the radiometric transport band balance. The stochastic perturbations of the measured signal afford the use of adequate filter algorithms. In the case of highly dynamical measurements it may even become necessary to improve the dynamics of the drive system. With essential improvements, the loading measurements can be performed far in front of the belt discharge location. For this purpose a solution is developed on the basis of an optimal control loop synthesis. A simpler solution is based on the optimal choise of the measuring point in order to compensate partially for the inertance of the drive. In addition a linear filter is used to process the radiometric signals. For the optimal design of this filter a method is used, which allows to limit the pulse response to a final time interval. As a consequence, analytical equations can be deduced for the calculation and discussion of the expected filter characteristic. (orig./DG)

  14. Interpreting the Densities of the Kuiper Belt's Dwarf Planets

    CERN Document Server

    Barr, Amy C

    2016-01-01

    Kuiper Belt objects with absolute magnitude less than 3 (radius $\\gtrsim$500 km), the dwarf planets, have a range of different ice/rock ratios, and are more rock-rich than their smaller counterparts. Many of these objects have moons, which suggests that collisions may have played a role in modifying their compositions. We show that the dwarf planets fall into two categories when analysed by their mean densities and satellite-to-primary size ratio. Systems with large moons, such as Pluto/Charon and Orcus/Vanth, can form in low-velocity grazing collisions in which both bodies retain their compositions. We propose that these systems retain a primordial composition, with a density of about 1.8 g/cm$^3$. Triton, thought to be a captured KBO, could have lost enough ice during its early orbital evolution to explain its rock-enrichment relative to the primordial material. Systems with small moons, Eris, Haumea, and Quaoar, formed from a different type of collision in which icy material, perhaps a few tens of percent ...

  15. Uraniferous mineralizations in the Kuusamo Schist Belt, northeastern Finland

    International Nuclear Information System (INIS)

    The Kouveraara Co-Cu-Au mineralization was found in 1982 with the aid of a geophysical ground survey. This survey was connected with research on the Kouvervaara uranium mineralization in the Early Proterozoic Kuusamo Schist Belt, located just south of the Arctic Circle. In further work, using the Kouvervaara sulphide mineralization as a reference, six Co and Au bearing sulphide mineralizations were discovered, with the help of low altitude aerial geophysical techniques. The Co-Au mineralizations, hosted by the Sericite Quartzite Formation, occur within the hydrothermally altered zones. These zones consist of chloritization, carbonatization, sulphidization, sericitization and albitization, the latter being the most extensive. Excluding the Juomasuo mineralization, uranium is only a trace element in these mineralizations. Other characteristic trace elements are molybdenum and tungsten. The Sivakkaharju and Konttiaho Co-Au-U-Mo mineralizations were found by radiometric ground surveys carried out in 1985 and 1986. These hydrothermal mineralizations occur within brecciated quartz-albite-carbonate rocks and are good manifestations of the positive correlation between uranium and gold in the Kuusamo area. Compared with the other sulphide mineralizations, the Au, U, and Mo contents are remarkably high. Genetically, the mineralizations in the Kuusamo area are associated with deep seated fracture and fault zones, controlled by ancient intracontinental hot spot activity and continental rifting. (author). 31 refs, 6 figs, 2 tabs

  16. Structural style of the Marathon thrust belt, West Texas

    Science.gov (United States)

    Hickman, Robert G.; Varga, Robert J.; Altany, Robert M.

    2009-09-01

    The Marathon portion of the Ouachita thrust belt consists of a highly deformed allochthonous wedge of Cambrian-Pennsylvanian slope strata (Marathon facies) that was transported to the northwest and emplaced over Pennsylvanian foredeep sediments. The foredeep strata in turn overlie early-middle Paleozoic shelfal sediments which are deformed by late Paleozoic basement-involved reverse faults. The Dugout Creek thrust is the basal thrust of the allochthon. Shortening in this sheet and overlying sheets is ˜80%. Steep imbricate faults link the Dugout Creek thrust to upper level detachments forming complex duplex zones. Progressive thrusting and shortening within the allochthon folded the upper level detachments and associated thrust sheets. The Caballos Novaculite is the most competent unit within the Marathon facies and controlled development of prominent detachment folds. Deeper imbricate sheets composed of the Late Pennsylvanian foredeep strata, and possibly early-middle Paleozoic shelfal sediments developed concurrently with emplacement of the Marathon allochthon and folded the overlying allochthon. Following termination of thrusting in the earliest Permian, subsidence and deposition shifted northward to the Delaware, Midland and Val Verde foreland basins.

  17. Belted kingfishers as ecological monitors of contamination: A review

    Energy Technology Data Exchange (ETDEWEB)

    Landrum, C.L. [North Texas Univ., Denton, TX (United States). Dept. of Biology; Ashwood, T.L.; Cox, D.K. [Oak Ridge National Lab., TN (United States)

    1993-03-01

    Aquatic systems serve as transport pathways and reservoirs for most of the contaminants known to be present on the Oak Ridge Reservation (ORR). Organisms that live in aquatic systems accumulate some of these contaminants from their food and directly from the water or sediment. A wide array of terrestrial organisms feeds on aquatic organisms and may accumulate contaminants from aquatic prey. The belted kingfisher (Ceryle alcyon) is a piscivorous and territorial avian species that may be a suitable monitor of contaminant accumulation at specific sites on the ORR. A kingfisher collected on White Oak Lake in 1991 had a {sup 137}Cs concentration of 568 pCi/g in muscle tissue, which exceeds levels found in any other waterfowl collected from the lake. An investigation into the efficacy of using the kingfisher as an ecological indicator of aquatic contaminants on the ORR was initiated in late August 1992. The primary objective of this study was to acquire information concerning the ecology of the kingfisher to determine how the species could be used within the framework of the Biological Monitoring and Abatement Program at Oak Ridge National Laboratory (ORNL). A second important objective of the study was to examine the possible somatic and reproductive effects of polychlorinated biphenyls (PCBs), Hg, and various radioactive contaminants on piscivorous birds by reviewing pollution ecology studies conducted on those species.

  18. Earthquake source characteristics along the arcuate Himalayan belt: Geodynamic implications

    Indian Academy of Sciences (India)

    Prosanta Kumar Khan; Md Afroz Ansari; S Mohanty

    2014-07-01

    The occurrences of moderate to large magnitude earthquakes and associated subsurface geological processes were critically examined in the backdrop of Indian plate obliquity, stress obliquity, topography, and the late Tertiary regional tectonics for understanding the evolving dynamics and kinematics in the central part of the Himalayas. The higher topographic areas are likely associated with the zones of depressions, and the lower topographic areas are found around the ridges located in the frontal part of the orogen. A positive correlation between plate and stress obliquities is established for this diffuse plate boundary. We propose that the zone of sharp bending of the descending Indian lithosphere is the nodal area of major stress accumulation which is released occasionally in form of earthquakes. The lateral geometry of the Himalayas shows clusters of seismicity at an angle of ∼20° from the centre part of the arc. Such spatial distribution is interpreted in terms of compression across the arc and extension parallel to the arc. This biaxial deformation results in the development of dilational shear fractures, observed along the orogenic belt, at an angle of ∼20° from the principal compressive stress axis.

  19. Geochronological review of Sambagawa metamorphic belt in Southwest Japan

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Based on almost all available published age data, the protolith ages, peak metamorphic ages and cooling rate of the Sambagawa metamorphic belt have been discussed and the latest constraints on the ages of the Sambagawa metamorphism and subduction-related accretionary evolutions were summarized. Peak metamorphic conditions attained within the Kuma nappe complex at ca. 145~185 Ma, and uplift through ca. 500℃ at ca. 150 Ma and 350~400℃ at ca. 110~ 115 Ma. The protolith sediments of the Besshi nappe complex were accumulated and subsequently progressively subducted and suffered high P-T prograde metamorphism during the Kuma nappe complex uplifting. The Besshi nappe complex arrived maximum metamorphic conditions at ca. 110 ~ 120 Ma and subsequently started rapid uplift with the cooling rate of ca. 14.2℃/Ma at ca. 75 ~85 Ma, followed with the cooling rate of ca. 6.0 ~8.9℃/Ma. The Oboke nappe complex started subduction later than other tectonic units and arrived the peak metamorphic conditions at ca. 75 Ma, which followed by the uplift with a cooling rate of ca. 8℃/Ma.

  20. The Gould Belt 'MISFITS' Survey: The Real Solar Neighborhood Protostars

    CERN Document Server

    Heiderman, Amanda

    2015-01-01

    We present an HCO$^{+}$ J=3-2 survey of Class 0+I and Flat SED young stellar objects (YSOs) found in the Gould Belt clouds by surveys with Spitzer. Our goal is to provide a uniform Stage 0+I source indicator for these embedded protostar candidates. We made single point HCO$^{+}$ J = 3-2 measurements toward the source positions at the CSO and APEX of 546 YSOs (89% of the Class 0+I + Flat SED sample). Using the criteria from van Kempen et al. (2009), we classify sources as Stage 0+I or bona fide protostars and find that 84% of detected sources meet the criteria. We recommend a timescale for the evolution of Stage 0+I (embedded protostars) of 0.54 Myr. We find significant correlations of HCO$^{+}$ integrated intensity with ${\\alpha}$ and $T_{bol}$ but not with $L_{bol}$. The detection fraction increases smoothly as a function of ${\\alpha}$ and $L_{bol}$, while decreasing smoothly with $T_{bol}$. Using the Stage 0+I sources tightens the relation between protostars and high extinction regions of the cloud; 89% of ...

  1. Volatile Loss and Classification of Kuiper Belt Objects

    CERN Document Server

    Johnson, R E; Young, L A; Volkov, A N; Schmidt, C

    2015-01-01

    Observations indicate that some of the largest Kuiper Belt Objects (KBOs) have retained volatiles in the gas phase, which implies the presence of an atmosphere that can affect their reflectance spectra and thermal balance. Volatile escape rates driven by solar heating of the surface were estimated by Schaller and Brown (2007) (SB) and Levi and Podolak (2009)(LP) using Jeans escape from the surface and a hydrodynamic model respectively. Based on recent molecular kinetic simulations these rates can be hugely in error (e.g., a factor of $\\sim 10^{16}$ for the SB estimate for Pluto). In this paper we estimate the loss of primordial N$_2$ for several large KBOs guided by recent molecular kinetic simulations of escape due to solar heating of the surface and due to UV/EUV heating of the upper atmosphere. For the latter we extrapolate simulations of escape from Pluto (Erwin et al. 2013) using the energy limited escape model recently validated for the KBOs of interest by molecular kinetic simulations (Johnson et al. 2...

  2. Initial highlights from the Herschel Gould Belt survey

    CERN Document Server

    André, Ph; Bontemps, S; Könyves, V; Motte, F; Schneider, N; Didelon, P; Minier, V; Saraceno, P; Ward-Thompson, D; Di Francesco, J; White, G; Molinari, S; Testi, L; Abergel, A; Griffin, M; Henning, Th; Royer, P; Merín, B; Vavrek, R; Attard, M; Arzoumanian, D; Wilson, C D; Ade, P; Aussel, H; Baluteau, J -P; Benedettini, M; Bernard, J -Ph; Blommaert, J A D L; Cambrésy, L; Cox, P; Di Giorgio, A; Hargrave, P; Hennemann, M; Huang, M; Kirk, J; Krause, O; Launhardt, R; Leeks, S; Pennec, J Le; Li, J Z; Martin, P; Maury, A; Olofsson, G; Omont, A; Peretto, N; Pezzuto, S; Prusti, T; Roussel, H; Russeil, D; Sauvage, M; Sibthorpe, B; Sicilia-Aguilar, A; Spinoglio, L; Waelkens, C; Woodcraft, A; Zavagno, A

    2010-01-01

    We summarize the first results from the Gould Belt survey, obtained toward the Aquila Rift and Polaris Flare regions during the 'science demonstration phase' of Herschel. Our 70-500 micron images taken in parallel mode with the SPIRE and PACS cameras reveal a wealth of filamentary structure, as well as numerous dense cores embedded in the filaments. Between ~ 350 and 500 prestellar cores and ~ 45-60 Class 0 protostars can be identified in the Aquila field, while ~ unbound starless cores and no protostars are observed in the Polaris field. The prestellar core mass function (CMF) derived for the Aquila region bears a strong resemblance to the stellar initial mass function (IMF), already confirming the close connection between the CMF and the IMF with much better statistics than earlier studies. Comparing and contrasting our Herschel results in Aquila and Polaris, we propose an observationally-driven scenario for core formation according to which complex networks of long, thin filaments form first within molecul...

  3. Storm/substorm signatures in the outer belt

    International Nuclear Information System (INIS)

    The response of the ring current region is compared for periods of storm and substorm activity, with an attempt to isolate the contributions of both processes. The authors investigate CRRES particle data in an overview format that allows the display of long-term variations of the outer radiation belt. They compare the evolution of the ring current population to indicators of storm (Dst) and substorm (AE) activity and examine compositional changes. Substorm activity leads to the intensification of the ring current at higher L (L ∼ 6) and lower ring current energies compared to storms (L ∼ 4). The O+/H+ ratio during substorms remains low, near 10%, but is much enhanced during storms (can exceed 100%). They conclude that repeated substorms with an AE ∼ 900 nT lead to a ΔDst of ∼ 30 nT, but do not contribute to Dst during storm main phase as substorm injections do not form a symmetric ring current during such disturbed times

  4. Baseline air quality evaluation for the Venezuelan Orinoco Bitumen Belt

    International Nuclear Information System (INIS)

    To achieve a harmonic relationship between oil exploration and production activities and the environment, Petroleos de Venezuela and its affiliated companies conducted environmental evaluations of the physical and bionic media in the Orinoco Bitumen Belt. This region covers an area of approximately 42000 km2 with estimated bitumen reserves on the order of 3 x 1012 barrels, one of the largest bitumen reservoirs in the world. This paper presents the results of a study of baseline air quality conditions: an emissions inventory, surface and upper layer meteorological conditions and measurements of air quality parameters of interest (CO, HC, NOx, SO2, H2S and T.S.P.) taken by a network of automated air quality stations using standard international reference techniques. The temporal (hourly and daily basis) and spatial air quality variability and the variables/activities that might determine the observed trends are discussed. NO, NO2, SO2 and H2S concentrations were lower than the detection limits of the analytical methods, while O3 and CO 1-hour average levels ranged from 5-30 ppb and 0.5-1.8 ppm, respectively, and T.S.P. daily means varied from 10-50 μg/m3, all of which is close to natural background concentrations. Maximum hourly average reactive hydrocarbon concentrations of 0.37 ppm were found near a producing oil field

  5. Two Color Populations of Kuiper Belt and Centaur Objects

    Science.gov (United States)

    Tegler, Stephen C.; Romanishin, William; Consolmagno, Guy

    2016-10-01

    We present new optical colors for 64 Kuiper belt objects (KBOs) and Centaur objects measured with the 1.8-meter Vatican Advanced Technology Telescope (VATT) and the 4.3-meter Discovery Channel Telescope (DCT). By combining these new colors with our previously published colors, we increase the sample size of our survey to 154 objects. Our survey is unique in that the uncertainties in our color measurements are less than half the uncertainties in the color measurements reported by other researchers in the literature. Small uncertainties are essential for discerning between a unimodal and a bimodal distribution of colors for these objects as well as detecting correlations between colors and orbital elements. From our survey, it appears red Centaurs have a broader color distribution than grey Centaurs. We find red Centaurs have a smaller orbital inclination angle distribution than grey Centaurs at the 99.3% confidence level. Furthermore, we find that our entire sample of KBOs and Centaurs exhibits bimodal colors at the 99.4% confidence level. KBOs and Centaurs with HV > 7.0 have bimodal colors at the 99.96% confidence level and KBOs with HV < 6.0 have bimodal colors at the 96.3% confidence level.We are grateful to the NASA Solar System Observations Program for support, NAU for joining the Discovery Channel Telescope Partnership, and the Vatican Observatory for the consistent allocation of telescope time over the last 12 years of this project.

  6. First results from the Herschel Gould Belt Survey in Taurus

    CERN Document Server

    Kirk, J M; Palmeirim, P; Andre, Ph; Griffin, M J; Hargrave, P J; Konyves, V; Bernard, J P; Nutter, D J; Sibthorpe, B; Di Francesco, J; Abergel, A; Arzoumanian, D; Benedettini, M; Bontemps, S; Elia, D; Hennemann, M; Hill, T; Men'shchikov, A; Motte, F; Nguyen-Luong, Q; Peretto, N; Pezzuto, S; Rygl, K L J; Sadavoy, S I; Schisano, E; Schneider, N; Testi, L; White, G

    2013-01-01

    The whole of the Taurus region (a total area of 52 sq. deg.) has been observed by the Herschel SPIRE and PACS instruments at wavelengths of 70, 160, 250, 350 and 500 {\\mu}m as part of the Herschel Gould Belt Survey. In this paper we present the first results from the part of the Taurus region that includes the Barnard 18 and L1536 clouds. A new source-finding routine, the Cardiff Source-finding AlgoRithm (CSAR), is introduced, which is loosely based on CLUMPFIND, but that also generates a structure tree, or dendrogram, which can be used to interpret hierarchical clump structure in a complex region. Sources were extracted from the data using the hierarchical version of CSAR and plotted on a mass-size diagram. We found a hierarchy of objects with sizes in the range 0.024-2.7 pc. Previous studies showed that gravitationally bound prestellar cores and unbound starless clumps appeared in different places on the mass-size diagram. However, it was unclear whether this was due to a lack of instrumental dynamic range ...

  7. Belted kingfishers as ecological monitors of contamination: A review

    International Nuclear Information System (INIS)

    Aquatic systems serve as transport pathways and reservoirs for most of the contaminants known to be present on the Oak Ridge Reservation (ORR). Organisms that live in aquatic systems accumulate some of these contaminants from their food and directly from the water or sediment. A wide array of terrestrial organisms feeds on aquatic organisms and may accumulate contaminants from aquatic prey. The belted kingfisher (Ceryle alcyon) is a piscivorous and territorial avian species that may be a suitable monitor of contaminant accumulation at specific sites on the ORR. A kingfisher collected on White Oak Lake in 1991 had a 137Cs concentration of 568 pCi/g in muscle tissue, which exceeds levels found in any other waterfowl collected from the lake. An investigation into the efficacy of using the kingfisher as an ecological indicator of aquatic contaminants on the ORR was initiated in late August 1992. The primary objective of this study was to acquire information concerning the ecology of the kingfisher to determine how the species could be used within the framework of the Biological Monitoring and Abatement Program at Oak Ridge National Laboratory (ORNL). A second important objective of the study was to examine the possible somatic and reproductive effects of polychlorinated biphenyls (PCBs), Hg, and various radioactive contaminants on piscivorous birds by reviewing pollution ecology studies conducted on those species

  8. Arable weed flora in the Western Siberian grain belt

    Directory of Open Access Journals (Sweden)

    Kämpf, Immo

    2016-02-01

    Full Text Available Between Ekaterinburg and Nowosibirsk, in the Western Siberian grain belt, spring wheat is grown on fertile Chernozem soils. Field and farm sizes are large but the land-use intensity per area is low compared to Central Europe. Fertilizers and pesticides are applied only in low to moderate quantities and yields range between 10 and 20 dt ha-1. We studied the arable weed flora in the northern forest steppe zone of Tyumen region using a randomized sampling design. Surprisingly, the species richness was only moderate, on average 9.8 ± 3.8 species per 100 m². Compared to weed communities of Bashkiria (Southern Ural and less intensively used arable land of Central Europe these numbers are rather low. Moreover, most of the recorded species were cosmopolitans or widely distributed throughout the temperate zone. We suggest that the land use intensity was high enough to reduce the density of a number of weed species in a way that they were not registered by our random sampling design. The limited conservational value of the weed vegetation of large grain fields in Tyumen leads to the conclusion that if intensification of land use is unavoidable, it should be directed to arable land and not to ex-arable land or ancient grassland, which is of higher conservation value.

  9. Size Distribution of Main-Belt Asteroids with High Inclination

    CERN Document Server

    Terai, Tsuyoshi

    2010-01-01

    We investigated the size distribution of high-inclination main-belt asteroids (MBAs) to explore asteroid collisional evolution under hypervelocity collisions of around 10 km/s. We performed a wide-field survey for high-inclination sub-km MBAs using the 8.2-m Subaru Telescope with the Subaru Prime Focus Camera (Suprime-Cam). Suprime-Cam archival data were also used. A total of 616 MBA candidates were detected in an area of 9.0 deg^2 with a limiting magnitude of 24.0 mag in the SDSS r filter. Most of candidate diameters were estimated to be smaller than 1 km. We found a scarcity of sub-km MBAs with high inclination. Cumulative size distributions (CSDs) were constructed using Subaru data and published asteroid catalogs. The power-law indexes of the CSDs were 2.17 +/- 0.02 for low-inclination ( 15 deg) MBAs in the 0.7-50 km diameter range. The high-inclination MBAs had a shallower CSD. We also found that the CSD of S-like MBAs had a small slope with high inclination, whereas the slope did not vary with inclinatio...

  10. Kuiper belt structure around nearby super-Earth host stars

    CERN Document Server

    Kennedy, Grant M; Marmier, Maxime; Greaves, Jane S; Wyatt, Mark C; Bryden, Geoffrey; Holland, Wayne; Lovis, Christophe; Matthews, Brenda C; Pepe, Francesco; Sibthorpe, Bruce; Udry, Stéphane

    2015-01-01

    We present new observations of the Kuiper belt analogues around HD 38858 and HD 20794, hosts of super-Earth mass planets within 1 au. As two of the four nearby G-type stars (with HD 69830 and 61 Vir) that form the basis of a possible correlation between low-mass planets and debris disc brightness, these systems are of particular interest. The disc around HD 38858 is well resolved with Herschel and we constrain the disc geometry and radial structure. We also present a probable JCMT sub-mm continuum detection of the disc and a CO J=2-1 upper limit. The disc around HD 20794 is much fainter and appears marginally resolved with Herschel, and is constrained to be less extended than the discs around 61 Vir and HD 38858. We also set limits on the radial location of hot dust recently detected around HD 20794 with near-IR interferometry. We present HARPS upper limits on unseen planets in these four systems, ruling out additional super-Earths within a few au, and Saturn-mass planets within 10 au. We consider the disc st...

  11. Imaging Jupiter's radiation belts down to 127 MHz with LOFAR

    CERN Document Server

    Girard, J N; Tasse, C; Hess, S; de Pater, I; Santos-Costa, D; Nenon, Q; Sicard, A; Bourdarie, S; Anderson, J; Asgekar, A; Bell, M E; van Bemmel, I; Bentum, M J; Bernardi, G; Best, P; Bonafede, A; Breitling, F; Breton, R P; Broderick, J W; Brouw, W N; Brüggen, M; Ciardi, B; Corbel, S; Corstanje, A; de Gasperin, F; de Geus, E; Deller, A; Duscha, S; Eislöffel, J; Falcke, H; Frieswijk, W; Garrett, M A; Grießmeier, J; Gunst, A W; Hessels, J W T; Hoeft, M; Hörandel, J; Iacobelli, M; Juette, E; Kondratiev, V I; Kuniyoshi, M; Kuper, G; van Leeuwen, J; Loose, M; Maat, P; Mann, G; Markov, S; McFadden, R; McKay-Bukowski, D; Moldon, J; Munk, H; Nelles, A; Norden, M J; Orru, E; Paas, H; Pandey-Pommier, M; Pizzo, R; Polatidis, A G; Reich, W; Röttgering, H; Rowlinson, A; Schwarz, D; Smirnov, O; Steinmetz, M; Swinbank, J; Tagger, M; Thoudam, S; Toribio, M C; Vermeulen, R; Vocks, C; van Weeren, R J; Wijers, R A M J; Wucknitz, O

    2015-01-01

    Context. Observing Jupiter's synchrotron emission from the Earth remains today the sole method to scrutinize the distribution and dynamical behavior of the ultra energetic electrons magnetically trapped around the planet (because in-situ particle data are limited in the inner magnetosphere). Aims. We perform the first resolved and low-frequency imaging of the synchrotron emission with LOFAR at 127 MHz. The radiation comes from low energy electrons (~1-30 MeV) which map a broad region of Jupiter's inner magnetosphere. Methods (see article for complete abstract) Results. The first resolved images of Jupiter's radiation belts at 127-172 MHz are obtained along with total integrated flux densities. They are compared with previous observations at higher frequencies and show a larger extent of the synchrotron emission source (>=4 $R_J$). The asymmetry and the dynamic of east-west emission peaks are measured and the presence of a hot spot at lambda_III=230 {\\deg} $\\pm$ 25 {\\deg}. Spectral flux density measurements ar...

  12. Dynamical delivery of volatiles to the outer main belt

    Science.gov (United States)

    Grazier, Kevin R.; Castillo-Rogez, Julie C.; Sharp, Philip W.

    2014-04-01

    We quantify the relative contribution of volatiles supplied from outer Solar System planetesimal reservoirs to large wet asteroids during the first few My after the beginning of the Solar System. To that end, we simulate the fate of planetesimals originating within different regions of the Solar System - and thus characterized by different chemical inventories - using a highly accurate integrator tuned to handle close planet/planetesimal encounters. The fraction of icy planetesimals crossing the Asteroid Belt was relatively significant, and our simulations show that planetesimals originating from the Jupiter/Saturn region were orders of magnitude more abundant than those stemming from the Uranus and Neptune regions when the planets were just embryos. As the planets reached their full masses the Jupiter/Saturn and Saturn/Uranus regions contributed similar fractions of planetesimals for any material remaining in these reservoirs late in the stage of planetary formation, This implies that large asteroids like Ceres accreted very little material enriched in low-eutectic volatiles (e.g., methanol, nitrogen and methane ices, etc.) and clathrate hydrates expected to condense at the very low temperatures predicted for beyond Saturn’s orbit in current early solar nebula models. Further, a large fraction of the content in organics of Ceres and neighboring ice-rich objects originates from the outer Solar System.

  13. Developing and improving underground haulage system in the Raspadskaya mine

    Energy Technology Data Exchange (ETDEWEB)

    Bol' shanin, N.I.; Sergienko, A.N.; Bakhtin, V.N.

    1980-06-01

    Coal haulage system in the Raspadskaya coal mine consists of several belt conveyors and vertical spiral chute conveyors. 1LT-80 and 2L-80 belt conveyors hauling coal from working faces cooperate with: PTK-1 and 1KSP-2 loaders; in breaking inclined planes 1LB-100, 2LB-120, 1LU-100 and 2LU-100 conveyors, which haul coal to the spiral chute conveyors, are installed. Capacity of a spiral chute conveyor is 700 t/h. The Raspadskaya haulage system is fully based on belt conveyors. One of its features is lack of storage capacity which could be used if the quantity of transported materials is temporarily higher than the haulage capacity of conveyors and chutes. Haulage capacity of both conveyors and spiral chutes is analyzed. In the case of conveyors their capacity depends mainly on width of the belt and speed of movement, and capacity of spiral chutes depends to a significant degree not only on size but also on moisture content in coal. When coal moisture increases from 3% to 8% haulage capacity decreases by 17 to 7 t/min. Some construction changes of the chutes are proposed which would prolong their service life 2 to 2.5 times. Proposals for modernizing the mine's haulage system are also made. They consist of: using belt conveyors with increased haulage capacity, modernizing spiral chutes and constructing temporary coal bunkers which could be used when haulage capacity of conveyors is lower than the flow of coal and rock.

  14. The Roles of Transport and Wave-Particle Interactions on Radiation Belt Dynamics

    Science.gov (United States)

    Fok, Mei-Ching; Glocer, Alex; Zheng, Qiuhua

    2011-01-01

    Particle fluxes in the radiation belts can vary dramatically during geomagnetic active periods. Transport and wave-particle interactions are believed to be the two main types of mechanisms that control the radiation belt dynamics. Major transport processes include substorm dipolarization and injection, radial diffusion, convection, adiabatic acceleration and deceleration, and magnetopause shadowing. Energetic electrons and ions are also subjected to pitch-angle and energy diffusion when interact with plasma waves in the radiation belts. Important wave modes include whistler mode chorus waves, plasmaspheric hiss, electromagnetic ion cyclotron waves, and magnetosonic waves. We investigate the relative roles of transport and wave associated processes in radiation belt variations. Energetic electron fluxes during several storms are simulated using our Radiation Belt Environment (RBE) model. The model includes important transport and wave processes such as substorm dipolarization in global MHD fields, chorus waves, and plasmaspheric hiss. We discuss the effects of these competing processes at different phases of the storms and validate the results by comparison with satellite and ground-based observations. Keywords: Radiation Belts, Space Weather, Wave-Particle Interaction, Storm and Substorm

  15. On the formation and evolution of asteroid belts and their potential significance for life

    CERN Document Server

    Martin, Rebecca G

    2012-01-01

    Suggestions have been made that asteroid belts may be important both for the existence of life and perhaps even for the evolution of complex life on a planet. Using numerical models for protoplanetary discs we calculate the location of the snow line, and we propose that asteroid belts are most likely to form in its vicinity. We then show that observations of warm dust in exo-solar systems, thought to be produced by collisions between asteroids in a belt, indicate that asteroid belts (when they exist), indeed coincide with the radial location and the temperature of the snow line. Giant planets form outside the snow line and prevent planet formation just inside of their orbit creating an asteroid belt there. However, the migration of giant planets through the asteroid belt likely disperses the compact formation. We examine existing observations of giant exo-planets and find that less than 4% are at radial locations outside of the snow line. This definitely may be the consequence of observational selection effec...

  16. Biomechanical caracterisation of lumbar belt by full-field techniques: Preliminary results

    CERN Document Server

    Bonnaire, Rebecca; Calmels, Paul; Convert, Reynald

    2013-01-01

    In France, 50% of the population per year is suffering from low back pain. Lumbar belt are frequently proposed as a part of the treatment of this pathology. However mechanical ways of working of this medical device is not clearly understood, but abdominal pressure is often related. So an optical method was developed in this study to measure strain in lumbar belt and trunk interface and to derive a pressure estimation. Optical method consisted of coupling fringe projection and digital image correlation (DIC). Measurement has been carried out on the right side of a manikin wearing a lumbar belt. Average strain is 0.2 and average pressure is 1 kPa. Continuation of this study will be comparison of strain and pressure in different areas of lumbar belt (left side, front and back) and comparison of different lumbar belts. Results will be used in a finite elements model to determine lumbar belt impact in intern body. In long term, this kind of study will be done on human.

  17. Discussion about the relationship between seismic belt and seismic statistical zone

    Institute of Scientific and Technical Information of China (English)

    潘华; 金严; 胡聿贤

    2003-01-01

    This paper makes a summary of status of delimitation of seismic zones and belts of China firstly in aspects of studying history, purpose, usage, delimiting principles, various presenting forms and main specialties. Then the viewpoints are emphasized, making geographical divisions by seismicity is just the most important purpose of delimiting seismic belts and the concept of seismic belt is also quite different from that of seismic statistical zone used in CPSHA method. The concept of seismic statistical zone and its history of evolvement are introduced too. Large differences between these two concepts exist separately in their statistical property, actual meaning, gradation, required scale, and property of refusing to overlap each other, aim and usage of delimitation. But in current engineering practice, these two concepts are confused. On the one hand, it causes no fit theory for delimiting seismic statistical zone in PSHA to be set up; on the other hand, researches about delimitation of seismic belts with purposes of seismicity zoning and studying on structural environment, mechanism of earthquake generating also pause to go ahead. Major conclusions are given in the end of this paper, that seismic statistical zone bases on the result of seismic belt delimiting, it only arises in and can be used in the especial PSHA method of China with considering spatially and temporally inhomogeneous seismic activities, and its concept should be clearly differentiated from the concept of seismic belt.

  18. Seismic tomography beneath the orogenic belts and adjacent basins of northwestern China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Three-dimensional velocity images of the crust and upper mantlebeneath orogenic belts and adjacent basins of the northwestern continent of China are reconstructed by seismic tomography, based on arrival data of P wave recorded in seismic networks in Xinjiang, Qinghai, Gansu of China and Kyrgyzstan. The velocity images of upper crust demonstrate the tectonic framework on the ground surface. High velocities are observed beneath orogenic belts, and low velocities are observed in the basins and depressions that are obviously related to unconsolidated sediments. The velocity image in mid-crust maintains the above features, and in addition low velocities appear in some earthquake regions and a low velocity boundary separates the western Tianshan Mts. from eastern Tianshan Mts. The orogenic belts and the northern Tibetan plateau have a Moho depth over 50 km, whereas the depths of the Moho in basins and depressions are smaller than 50 km. The velocity images of upper mantle clearly reveal the colliding relationship and location of deep boundaries of the continental blocks in northwestern China, indicating a weakness of the upper mantle structure of orogenic belts. The top depth of upper mantle asthenosphere varies from place to place. It seems shallower under the northern Tibetan plateau, Altay and Qilian Mts., and deeper under the Tarim and Tianshan regions. Hot mantle probably rose to the bottom of some orogenic belts along tectonic boundaries when continental blocks collided to each other. Therefore their dynamic features are closely correlated to the formation and evolution of orogenic belts in northwestern China.

  19. Development of Computational Models for Coiling Process with the Belt Wrapper

    Science.gov (United States)

    Park, Yonghui; Park, Hyunchul

    2016-10-01

    This study introduces coiling mechanism with the belt wrapper to understand a force equilibrium for successful coiling. By establishing a finite element (FE) model, strips were coiled 2 to 3 rotations by the belt wrapper on the sleeve without coiling tension T, then T was applied to the opposite side of the strips near the pinch roller, and the belt wrapper was removed from the strip coil at the same time. Additionally, analytical model corresponding to FE model was defined by thick and thin cylinder theorems to quantize coiling mechanisms. Especially elasticity of the belt wrapper E [N/m2], coiling tension T [N/m2], and friction coefficient μ were checked on how these variables affect each other, were converted into pressure P [N/m2], and P were used to calculate when the strip coil come untied. For instance, the strip coil came untied when E was lower than 1 × 109 N/m2 corresponding to ( {{{{Pressure}} {{on}} {{outmost}} {{of the belt wrapper}} P_{{o,belt}} }/{{{Pressure} {{on}} {{innermost}} {{of the sleeve}} P_{{i,sleeve}} }} = 0.877} ) . Lastly, radial stress on the outmost of the sleeve σ r,o,sleeve [N/m2] according to E were compared to the previous coiling method with the grooved joint to see how these methods are different. Based on these results, this paper suggests coiling criteria to avoid coiling failure of slip of the strip coil.

  20. The Hawaii Trails Project: Comet-Hunting in the Main Asteroid Belt

    CERN Document Server

    Hsieh, Henry H

    2009-01-01

    The mysterious solar system object 133P/(7968) Elst-Pizarro is dynamically asteroidal, yet displays recurrent comet-like dust emission. Two scenarios were hypothesized to explain this unusual behavior: (1) 133P is a classical comet from the outer solar system that has evolved onto a main-belt orbit, or (2) 133P is a dynamically ordinary main-belt asteroid on which subsurface ice has recently been exposed. If (1) is correct, the expected rarity of a dynamical transition onto an asteroidal orbit implies that 133P could be alone in the main belt. In contrast, if (2) is correct, other icy main-belt objects should exist and could also exhibit cometary activity. Believing 133P to be a dynamically ordinary, yet icy main-belt asteroid, I set out to test the primary prediction of the hypothesis: that 133P-like objects should be common and could be found by an appropriately designed observational survey. I conducted just such a survey -- the Hawaii Trails Project -- of selected main-belt asteroids in a search for objec...