WorldWideScience

Sample records for grounding electric blasting

  1. 29 CFR 1926.906 - Initiation of explosive charges-electric blasting.

    Science.gov (United States)

    2010-07-01

    ... blasting caps shall not be grounded. (j) In underground operations when firing from a power circuit, a..., shall use only blasting galvanometers or other instruments that are specifically designed for this... 29 Labor 8 2010-07-01 2010-07-01 false Initiation of explosive charges-electric blasting....

  2. Modeling and Simulating Blast Effects on Electric Substations

    Energy Technology Data Exchange (ETDEWEB)

    Lyle G. Roybal; Robert F. Jeffers; Kent E. McGillivary; Tony D. Paul; Ryan Jacobson

    2009-05-01

    A software simulation tool was developed at the Idaho National Laboratory to estimate the fragility of electric substation components subject to an explosive blast. Damage caused by explosively driven fragments on a generic electric substation was estimated by using a ray-tracing technique to track and tabulate fragment impacts and penetrations of substation components. This technique is based on methods used for assessing vulnerability of military aircraft and ground vehicles to explosive blasts. An open-source rendering and ray-trace engine was used for geometric modeling and interactions between fragments and substation components. Semi-empirical material interactions models were used to calculate blast parameters and simulate high-velocity material interactions between explosively driven fragments and substation components. Finally, a Monte Carlo simulation was added to model the random nature of fragment generation allowing a skilled analyst to predict failure probabilities of substation components.

  3. Predictions of experimentally observed stochastic ground vibrations induced by blasting.

    Science.gov (United States)

    Kostić, Srđan; Perc, Matjaž; Vasović, Nebojša; Trajković, Slobodan

    2013-01-01

    In the present paper, we investigate the blast induced ground motion recorded at the limestone quarry "Suva Vrela" near Kosjerić, which is located in the western part of Serbia. We examine the recorded signals by means of surrogate data methods and a determinism test, in order to determine whether the recorded ground velocity is stochastic or deterministic in nature. Longitudinal, transversal and the vertical ground motion component are analyzed at three monitoring points that are located at different distances from the blasting source. The analysis reveals that the recordings belong to a class of stationary linear stochastic processes with Gaussian inputs, which could be distorted by a monotonic, instantaneous, time-independent nonlinear function. Low determinism factors obtained with the determinism test further confirm the stochastic nature of the recordings. Guided by the outcome of time series analysis, we propose an improved prediction model for the peak particle velocity based on a neural network. We show that, while conventional predictors fail to provide acceptable prediction accuracy, the neural network model with four main blast parameters as input, namely total charge, maximum charge per delay, distance from the blasting source to the measuring point, and hole depth, delivers significantly more accurate predictions that may be applicable on site. We also perform a sensitivity analysis, which reveals that the distance from the blasting source has the strongest influence on the final value of the peak particle velocity. This is in full agreement with previous observations and theory, thus additionally validating our methodology and main conclusions.

  4. Modelling the Source of Blasting for the Numerical Simulation of Blast-Induced Ground Vibrations: A Review

    Science.gov (United States)

    Ainalis, Daniel; Kaufmann, Olivier; Tshibangu, Jean-Pierre; Verlinden, Olivier; Kouroussis, Georges

    2017-01-01

    The mining and construction industries have long been faced with considerable attention and criticism in regard to the effects of blasting. The generation of ground vibrations is one of the most significant factors associated with blasting and is becoming increasingly important as mining sites are now regularly located near urban areas. This is of concern to not only the operators of the mine but also residents. Mining sites are subjected to an inevitable compromise: a production blast is designed to fragment the utmost amount of rock possible; however, any increase in the blast can generate ground vibrations which can propagate great distances and cause structural damage or discomfort to residents in surrounding urban areas. To accurately predict the propagation of ground vibrations near these sensitive areas, the blasting process and surrounding environment must be characterised and understood. As an initial step, an accurate model of the source of blast-induced vibrations is required. This paper presents a comprehensive review of the approaches to model the blasting source in order to critically evaluate developments in the field. An overview of the blasting process and description of the various factors which influence the blast performance and subsequent ground vibrations are also presented. Several approaches to analytically model explosives are discussed. Ground vibration prediction methods focused on seed waveform and charge weight scaling techniques are presented. Finally, numerical simulations of the blasting source are discussed, including methods to estimate blasthole wall pressure time-history, and hydrodynamic codes.

  5. Analysis of the blasting effect on the electric shove loading efficiency of the open pit

    Institute of Scientific and Technical Information of China (English)

    FU Tian-guang; SUN Ying

    2008-01-01

    The connection between blasting cost and comprehensive cost is the main concern. Some blasting effect factors (such as unit explosive consumption, uniformity of blockness, shape and porosity of blasting heap), which had an influence on electric shove loading efficiency, were analyzed. In the end a project to properly increase in blasting cost to decrease the comprehensive cost was put forward. At the same time, the hole-by-hole blasting is effective technology to improve blasting effect.

  6. Soil Stabilisation Using Ground Granulated Blast Furnace Slag

    Directory of Open Access Journals (Sweden)

    Ashish Kumar Pathak

    2014-05-01

    Full Text Available Stabilisation is a broad sense for the various methods employed and modifying the properties of a soil to improve its engineering performance and used for a variety of engineering works. In today‟s day soil stabilisation is the major problem for civil engineers, either for construction of road and also for increasing the strength or stability of soil and reduces the construction cost. In this thesis the soil are stabilised by ground granulated blast furnace slag (GGBS and this material is obtained from the blast furnace of cement plant, which is the byproduct of iron (from ACC plant, sindri. It is generally obtained in three shaped one is air cooled, foamed shaped and another is in granulated shaped. The use of by-product materials for stabilisation has environmental and economic benefits. Ground granulated blast furnace slag (GGBS material is used in the current work to stabilise soil (clay. The main objectives of this research were to investigate the effect of GGBS on the engineering property (optimum moisture content and maximum dry density, plastic limit, liquid limit, compaction, unconfined compressive strength, triaxial and California bearing ratio test of the soil and determine the engineering properties of the stabilised.

  7. Blasting and Blast Effects in Cold Regions. Part 3. Explosions in Ground Materials

    Science.gov (United States)

    1989-05-01

    entries in Table 8 stuggest 20’ to 26’ for for most materials tends to be around 200 when the equivalent sideslope, while the last four entries 3t0 Fable...34 to 47 . rocal of volume per unit weight is a specific energy Iwo entries in -able 8 (small-scale tests in sand- if multiplied by the energy per unit...the best I I approximation at small scaled radii from ground Explcsion Sensor zero for a deep blast, with square root scaling giv- I Rock Rock2 Rock

  8. Numerical Simulations of Blast Loads from Near-Field Ground Explosions in Air

    Science.gov (United States)

    Dobrociński, Stanisław; Flis, Leszek

    2015-12-01

    Numerical simulations of air blast loading in the near-field acting on the ground have been performed. A simplified blast model based on empirical blast loading data representing spherical and hemispherical explosive shapes has been simulated. Conwep is an implementation of the empirical blast models presented by Kingery and Bulmash, which is also implemented in the commercial code LS-DYNA based on work done by Rahnders-Pehrson and Bannister. This makes it possible to simulate blast loads acting on structures representing spherical and hemispherical explosive shapes of TNT with reasonable computational effort as an alternative to the SPH and Eulerian model. The CPU time for the simplified blast model is however considerably shorter and may still be useful in time consuming concept studies. Reasonable numerical results using reasonable model sizes can be achieved not only for modelling near-field explosions in air but most areas of geotechnical. Calculation was compared with blast SPH and Eulerian model.

  9. Numerical Simulations of Blast Loads from Near-Field Ground Explosions in Air

    Directory of Open Access Journals (Sweden)

    Dobrociński Stanisław

    2015-12-01

    Full Text Available Numerical simulations of air blast loading in the near-field acting on the ground have been performed. A simplified blast model based on empirical blast loading data representing spherical and hemispherical explosive shapes has been simulated. Conwep is an implementation of the empirical blast models presented by Kingery and Bulmash, which is also implemented in the commercial code LS-DYNA based on work done by Rahnders-Pehrson and Bannister. This makes it possible to simulate blast loads acting on structures representing spherical and hemispherical explosive shapes of TNT with reasonable computational effort as an alternative to the SPH and Eulerian model. The CPU time for the simplified blast model is however considerably shorter and may still be useful in time consuming concept studies. Reasonable numerical results using reasonable model sizes can be achieved not only for modelling near-field explosions in air but most areas of geotechnical. Calculation was compared with blast SPH and Eulerian model.

  10. Electrical Ground Support Equipment Fabrication, Specification for

    Science.gov (United States)

    Denson, Erik C.

    2014-01-01

    This document specifies parts, materials, and processes used in the fabrication, maintenance, repair, and procurement of electrical and electronic control and monitoring equipment associated with ground support equipment (GSE) at the Kennedy Space Center (KSC).

  11. Analysis of the blasting effect on the electric shove loading efficiency of the open pit

    Institute of Scientific and Technical Information of China (English)

    FU Tian-guang; SUN Ying

    2008-01-01

    The connection between blasting cost and comprehensive cost is the main concern.Some blasting effect factors (such as unit explosive consumption,uniformity of blockness,shape and porosity of blasting heap),which had an influence on electric shove loading efficiency,were analyzed.In the end a project to properly increase in blasting cost to decrease the comprehensive cost was put forward.At the same time,the hole-by-hole blasting is effective technology to improve blasting effect.

  12. OPTIMAL PARAMETERS OF BLASTING IN TUNNELS USING PATRONED AND PUMPED EXPLOSIVES WITH ELECTRIC AND NON-ELECTRIC INITIATION

    Directory of Open Access Journals (Sweden)

    Zvonimir Deković

    2003-12-01

    Full Text Available The parameters of drilling and blasting procedures during excavation of Grič and mala Kapela Tunnels are presented in this work. The tunnels are being constructed according to NATM (New Austrian Tunneling Method in two parallel tubes. By Comparison of blasting with patroned and pumped explosives and electric and non-electric mode of initiation, optimal technological parameters have been defined concerning duration of blasting working cycle, progress, tunnel category and seismic effects of blasting on the tunnel support system of the parallel tunnel tube.

  13. 46 CFR 105.30-5 - Grounding of electrical equipment.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Grounding of electrical equipment. 105.30-5 Section 105... VESSELS COMMERCIAL FISHING VESSELS DISPENSING PETROLEUM PRODUCTS Electrical Requirements § 105.30-5 Grounding of electrical equipment. (a) All electrical equipment shall be grounded to the vessel's...

  14. Electrical Grounding - a Field for Geophysicists and Electrical Engineers Partnership

    Science.gov (United States)

    Freire, P. F.; Pane, E.; Guaraldo, N.

    2012-12-01

    Technology for designing ground electrodes for high-voltage direct current transmission systems (HVDC) has being using in the last years, deep soil models based on a wide range of geophysical methods. These models shall include detailed representation of shallow soil, down to 100 meters, in order to allow the evaluation of the soil conditions where the ground electrodes will be buried. Also deep soil models are needed, to be used for the interference studies, which shall represent a soil volume of about 15 km deep and a surface area of about 15 to 30 km radius. Large facilities for power plants (hydroelectric and wind farms, for example) and industrial complexes (such as petrochemical plants) has become usual at the current stage of Brazil industrialization. Grounding mats for these facilities are made of a buried cooper mesh, interconnected to a wide variety of metallic masses, such as steel reinforced concrete foundations, ducts in general etc. These grounding systems may present dimensions with the order of hundreds of meters, and, at least in Brazil, are usually calculated by using electrical resistivity soil models, based on short spacing Wenner measurements (with maximum spacing of about 64 m.). The soil model shall be the best possible representation of the environment in which the grounding electrodes are immersed, for the purpose of calculation of resistance or for digital simulation. The model to be obtained is limited by the amount and quality of soil resistivity measurements are available, and the resources to be used in the calculations and simulations. Geophysics uses a wide range of technologies for exploring subsoil, ranging from surface measurements to wells logging - seismic, gravimetric, magnetic, electrical, electromagnetic and radiometric. The electrical and electromagnetic methods includes various measurement techniques (Wenner, Schlumberger, TDEM, Magneto-telluric etc.), which together allow the development of complex resistivity soil models

  15. 46 CFR 169.676 - Grounded electrical systems.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Grounded electrical systems. 169.676 Section 169.676... Machinery and Electrical Electrical Installations Operating at Potentials of 50 Volts Or More on Vessels of Less Than 100 Gross Tons § 169.676 Grounded electrical systems. (a) Except as provided in paragraph...

  16. Simultaneous investigation of blast induced ground vibration and airblast effects on safety level of structures and human in surface blasting

    Institute of Scientific and Technical Information of China (English)

    Faramarzi Farhad⇑; Ebrahimi Farsangi Mohammad Ali; Mansouri Hamid

    2014-01-01

    The significance of studying, monitoring and predicting blast induced vibration and noise level in mining and civil activities is justified in the capability of imposing damages, sense of uncertainty due to negative psychological impacts on involved personnel and also judicial complaints of local inhabitants in the nearby area. This paper presents achieved results during an investigation carried out at Sungun Copper Mine, Iran. Besides, the research also studied the significance of blast induced ground vibration and air-blast on safety aspects of nearby structures, potential risks, frequency analysis, and human response. According to the United States Bureau of Mines (USBM) standard, the attenuation equations were devel-oped using field records. A general frequency analysis and risk evaluation revealed that:94%of generated frequencies are less than 14 Hz which is within the natural frequency of structures that increases risk of damage. At the end, studies of human response showed destructive effects of the phenomena by ranging between 2.54 and 25.40 mm/s for ground vibrations and by the average value of 110 dB for noise levels which could increase sense of uncertainty among involved employees.

  17. A Comparative Study of Ground and Underground Vibrations Induced by Bench Blasting

    Directory of Open Access Journals (Sweden)

    Xiuzhi Shi

    2016-01-01

    Full Text Available Ground vibrations originating from bench blasting may cause damage to slopes, structures, and underground workings in close proximity to an operating open-pit mine. It is important to monitor and predict ground vibration levels induced by blasting and to take measures to reduce their hazardous effects. The aims of this paper are to determine the weaker protection objects by comparatively studying bench blasting induced vibrations obtained at surface and in an underground tunnel in an open-pit mine and thus to seek vibration control methods to protect engineering objects at the site. Vibrations arising from measurement devices at surface and in an underground tunnel at the Zijinshan Open-Pit Mine were obtained. Comparative analysis of the peak particle velocities shows that, in the greatest majority of cases, surface values are higher than underground values for the same vibration distance. The transmission laws of surface and underground vibrations were established depending on the type of rock mass, the explosive charge, and the distance. Compared with the Chinese Safety Regulations for Blasting (GB6722-2014, the bench blasting induced vibrations would not currently cause damage to the underground tunnel. According to the maximum allowable peak particle velocities for different objects, the permitted maximum charges per delay are obtained to reduce damage to these objects at different distances.

  18. A Numerical Study on the Screening of Blast-Induced Waves for Reducing Ground Vibration

    Science.gov (United States)

    Park, Dohyun; Jeon, Byungkyu; Jeon, Seokwon

    2009-06-01

    Blasting is often a necessary part of mining and construction operations, and is the most cost-effective way to break rock, but blasting generates both noise and ground vibration. In urban areas, noise and vibration have an environmental impact, and cause structural damage to nearby structures. Various wave-screening methods have been used for many years to reduce blast-induced ground vibration. However, these methods have not been quantitatively studied for their reduction effect of ground vibration. The present study focused on the quantitative assessment of the effectiveness in vibration reduction of line-drilling as a screening method using a numerical method. Two numerical methods were used to analyze the reduction effect toward ground vibration, namely, the “distinct element method” and the “non-linear hydrocode.” The distinct element method, by particle flow code in two dimensions (PFC 2D), was used for two-dimensional parametric analyses, and some cases of two-dimensional analyses were analyzed three-dimensionally using AUTODYN 3D, the program of the non-linear hydrocode. To analyze the screening effectiveness of line-drilling, parametric analyses were carried out under various conditions, with the spacing, diameter of drill holes, distance between the blasthole and line-drilling, and the number of rows of drill holes, including their arrangement, used as parameters. The screening effectiveness was assessed via a comparison of the vibration amplitude between cases both with and without screening. Also, the frequency distribution of ground motion of the two cases was investigated through fast Fourier transform (FFT), with the differences also examined. From our study, it was concluded that line-drilling as a screening method of blast-induced waves was considerably effective under certain design conditions. The design details for field application have also been proposed.

  19. Ground granulated blast furnace slag efficiency coefficient (k value) in concrete. Applications and limits

    Energy Technology Data Exchange (ETDEWEB)

    Sanjuan, M. A.; Pineiro, A.; Rodriguez, O.

    2011-07-01

    Recently, a k-value for ground granulated blast-furnace slag or k-value has been added to the revision of the European standard EN 206-1:2000. The proposed values during the discussions in the working groups were very different because in most of cases the compressive strength was the only characteristic considered; while only in few cases the concrete durability was taken into account when ground granulated blast-furnace slag is added directly to the mix. Advantages and disadvantages of the k-values found in the literature are discussed in this paper. The final conclusion may be summarised suggesting a logical proposal of addressing to each country the choice of the k-value in function of the concrete application, environment and placing conditions selected according to their own experience. (Author) 15 refs.

  20. Grounding devices of electrical equipment's installation and check to maintain

    Institute of Scientific and Technical Information of China (English)

    王鹏

    2009-01-01

    At this stage in real life,the incidents of electricity are increasing,the main reason is that the subjective sense is weak,non-importance,especially the operation and maintenance is more neglected,and even there is no sense in this area.In this paper,based on electrical equipment grounding system for use in practice,simple introdusing grounding device of electrical equipment's installation and maintenance checks.

  1. REDUCTION OF GROUND MOTION INTENSITY CAUSED BY BLASTING ON STONE QUARRIES"HERCEGOVAC" AND "MAX-STOJA"

    Directory of Open Access Journals (Sweden)

    Marin Petrov

    1993-12-01

    Full Text Available Ground motion intensity caused by deep-hole blasting on the stone quarries »Hercegovac« and »Max-Stoja« was determined by measuring of ground vibrations magnitudes and by interpretation of measuring results under world damage criteria for structures. Reduction of ground motion intensity was realized on the basis of calculation of permissible charge quantity per ignition level (the paper is published in Croatian.

  2. Soft Computing Approach to Evaluate and Predict Blast-Induced Ground Vibration

    Science.gov (United States)

    Khandelwal, Manoj

    2010-05-01

    Drilling and blasting is still one of the major economical operations to excavate a rock mass. The consumption of explosive has been increased many folds in recent years. These explosives are mainly used for the exploitation of minerals in mining industry or the removal of undesirable rockmass for community development. The amount of chemical energy converted into mechanical energy to fragment and displace the rockmass is minimal. Only 20 to 30% of this explosive energy is utilized for the actual fragmentation and displacement of rockmass and rest of the energy is wasted in undesirable ill effects, like, ground vibration, air over pressure, fly rock, back break, noise, etc. Ground vibration induced due to blasting is very crucial and critical as compared to other ill effects due to involvement of public residing in the close vicinity of mining sites, regulating and ground vibration standards setting agencies together with mine owners and environmentalists and ecologists. Also, with the emphasis shifting towards eco-friendly, sustainable and geo-environmental activities, the field of ground vibration have now become an important and imperative parameter for safe and smooth running of any mining and civil project. The ground vibration is a wave motion, spreading outward from the blast like ripples spreading outwards due to impact of a stone dropped into a pond of water. As the vibration passes through the surface structures, it induces vibrations in those structures also. Sometimes, due to high ground vibration level, dwellings may get damaged and there is always confrontation between mine management and the people residing in the surroundings of the mine area. There is number of vibration predictors available suggested by different researchers. All the predictors estimate the PPV based on mainly two parameters (maximum charge used per delay and distance between blast face to monitoring point). However, few predictors considered attenuation/damping factor too. For

  3. Forensic Assessment on Ground Instability Using Electrical Resistivity Imaging (ERI)

    Science.gov (United States)

    Hazreek, Z. A. M.; Azhar, A. T. S.; Aziman, M.; Fauzan, S. M. S. A.; Ikhwan, J. M.; Aishah, M. A. N.

    2017-02-01

    Electrical resistivity imaging (ERI) was used to evaluate the ground settlement in local scale at housing areas. ERI and Borehole results were used to interpret the condition of the problematic subsurface profile due to its differential stiffness. Electrical resistivity of the subsurface profile was measured using ABEM SAS4000 equipment set. ERI results using electrical resistivity anomaly on subsurface materials resistivity shows the subsurface profile exhibited low (1 - 100 Ωm) and medium (> 100 Ωm) value (ERV) representing weak to firm materials. The occurrences of soft to medium cohesive material (SPT N value = 2 - 7) and stiff cohesive material (SPT N ≥ 8) in local scale has created inconsistency of the ground stability condition. Moreover, it was found that a layer of organic decayed wood (ERV = 43 ˜ 29 Ωm & SPT N = 15 ˜ 9) has been buried within the subsurface profile thus weaken the ground structure and finally promoting to the ground settlement. The heterogeneous of the subsurface material presented using integrated analysis of ERI and borehole data enabled ground settlement in this area to be evaluated. This is the major factor evaluating ground instability in the local scale. The result was applicable to assist in planning a strategy for sustainable ground improvement of local scale in fast, low cost, and large data coverage.

  4. Installation and Assembly, Electrical Ground Support Equipment (GSE), Specification for

    Science.gov (United States)

    Denson, Erik C.

    2014-01-01

    This specification covers the general workmanship requirements and procedures for the complete installation and assembly of electrical ground support equipment (EGSE) such as terminal distributors, junction boxes, conduit and fittings, cable trays and accessories, interconnecting cables (including routing requirements), motor-control equipment, and necessary hardware as specified by the applicable contract and drawings.

  5. The effects of structural setting on the azimuthal velocities of blast induced ground motion in perlite

    Energy Technology Data Exchange (ETDEWEB)

    Beattie, S.G. [New Mexico Inst. of Mining and Technology, Socorro, NM (United States)

    1995-02-01

    A series of small scale explosive tests were performed during the spring of 1994 at a perlite mine located near Socorro, NM. The tests were designed to investigate the azimuthal or directional relationship between small scale geologic structures such as joints and the propagation of explosively induced ground motion. Three shots were initiated within a single borehole located at ground zero (gz) at depths varying from the deepest at 83 m (272 ft) to the shallowest at 10 m (32 ft). The intermediate shot was initiated at a depth of 63 m (208 ft). An array of three component velocity and acceleration transducers were placed in two concentric rings entirely surrounding the single shot hole at 150 and 300 azimuths as measured from ground zero. Data from the transducers was then used to determine the average propagation velocity of the blast vibration through the rock mass at the various azimuths. The rock mass was mapped to determine the prominent joint orientations (strike and dip) and the average propagation velocities were correlated with this geologic information. The data from these experiments shows that there is a correlation between the orientation of prominent joints and the average velocity of ground motion. It is theorized that this relationship is due to the relative path the ground wave follows when encountering a joint or structure within the rock mass. The more prominent structures allow the wave to follow along their strike thereby forming a sort of channel or path of least resistance and in turn increasing the propagation velocity. Secondary joints or structures may act in concert with more prominent features to form a network of channels along which the wave moves more freely than it may travel against the structure. The amplitudes of the ground motion was also shown to vary azimuthally with the direction of the most prominent structures.

  6. Chloride leaching from air pollution control residues solidified using ground granulated blast furnace slag.

    Science.gov (United States)

    Lampris, Christos; Stegemann, Julia A; Cheeseman, Christopher R

    2008-11-01

    Ground granulated blast furnace slag (ggbs) has been used to solidify air pollution control (APC) residues obtained from a major UK energy-from-waste plant. Samples were prepared with ggbs additions between 10 and 50 wt% of total dry mass and water/solids ratios between 0.35 and 0.80. Consistence, setting time, compressive strength and leaching characteristics have been investigated. Results indicated that the highly alkaline nature of APC residues due to the presence of free lime can be used to activate ggbs hydration reactions. Increasing ggbs additions and reducing the water content resulted in increased compressive strengths, with 50 wt% ggbs samples having average 28 d strengths of 20.6 MPa. Leaching tests indicate low physical encapsulation and minimal chemical fixation of chloride in ggbs solidified APC residues. The results suggest that more than 50 wt% ggbs additions would be required to treat APC residues to meet the current waste acceptance criteria limits for chloride.

  7. Pore solution chemistry of alkali-activated ground granulated blast-furnace slag

    Energy Technology Data Exchange (ETDEWEB)

    Song, S.; Jennings, H.M. [Northwestern Univ., Evanston, IL (United States)

    1999-02-01

    The chemical composition and pH of the pore solution extracted from six different ground granulated blast-furnace slag (GGBFS) pastes were determined. The concentrations of Si, Ca, Al, and Mg are functions of the pH of the aqueous phase, with high pH associated with the higher concentrations of Si and Al and the lower concentrations of Ca and Mg. When GGBFS is mixed with an aqueous phase with pH higher than 11.5, the reaction is activated or accelerated. The main hydration product was identified as C-S-H, and hydrotalcite, at later stages of hydration, was observed in the pastes with an aqueous phase of a high pH. The effect of pore solution on the alkali activation of GGBFS is discussed with reference to the hydration products.

  8. Constellation Program Electrical Ground Support Equipment Research and Development

    Science.gov (United States)

    McCoy, Keegan S.

    2010-01-01

    At the Kennedy Space Center, I engaged in the research and development of electrical ground support equipment for NASA's Constellation Program. Timing characteristics playa crucial role in ground support communications. Latency and jitter are two problems that must be understood so that communications are timely and consistent within the Kennedy Ground Control System (KGCS). I conducted latency and jitter tests using Alien-Bradley programmable logic controllers (PLCs) so that these two intrinsic network properties can be reduced. Time stamping and clock synchronization also play significant roles in launch processing and operations. Using RSLogix 5000 project files and Wireshark network protocol analyzing software, I verified master/slave PLC Ethernet module clock synchronization, master/slave IEEE 1588 communications, and time stamping capabilities. All of the timing and synchronization test results are useful in assessing the current KGCS operational level and determining improvements for the future.

  9. Mechanisms of hydrogen sulfide removal by ground granulated blast furnace slag amended soil.

    Science.gov (United States)

    Xie, Mengyao; Leung, Anthony Kwan; Ng, Charles Wang Wai

    2017-02-06

    Ground granulated blast furnace slag (GGBS) amended soil has been found able to remove gaseous hydrogen sulfide (H2S). However, how H2S is removed by GGBS amended soil and why GGBS amended soil can be regenerated to remove H2S are not fully understood. In this study, laboratory column tests together with chemical analysis were conducted to investigate and reveal the mechanisms of H2S removal process in GGBS amended soil. Sulfur products formed on the surface of soil particle and in pore water were quantified. The test results reveal that the reaction between H2S and GGBS amended soil was a combined process of oxidation and acid-base reaction. The principal mechanism to remove H2S in GGBS amended soil was through the formation of acid volatile sulfide (AVS), elemental sulfur and thiosulfate. Soil pH value decreased gradually during regeneration and reuse cycles. It is found that the AVS plays a significant role in H2S removal during regeneration and reuse cycles. Adding GGBS increased the production of AVS and at the same time suppressed the formation of elemental sulfur. This mechanism is found to be more prominent when the soil water content is higher, leading to increased removal capacity.

  10. Characterisation of magnesium potassium phosphate cements blended with fly ash and ground granulated blast furnace slag

    Energy Technology Data Exchange (ETDEWEB)

    Gardner, Laura J.; Bernal, Susan A.; Walling, Samuel A.; Corkhill, Claire L.; Provis, John L.; Hyatt, Neil C., E-mail: n.c.hyatt@sheffield.ac.uk

    2015-08-15

    Magnesium potassium phosphate cements (MKPCs), blended with 50 wt.% fly ash (FA) or ground granulated blast furnace slag (GBFS) to reduce heat evolution, water demand and cost, were assessed using compressive strength, X-ray diffraction (XRD), scanning electron microscopy (SEM) and nuclear magnetic resonance (NMR) spectroscopy on {sup 25}Mg, {sup 27}Al, {sup 29}Si, {sup 31}P and {sup 39}K nuclei. We present the first definitive evidence that dissolution of the glassy aluminosilicate phases of both FA and GBFS occurred under the pH conditions of MKPC. In addition to the main binder phase, struvite-K, an amorphous orthophosphate phase was detected in FA/MKPC and GBFS/MKPC systems. It was postulated that an aluminium phosphate phase was formed, however, no significant Al–O–P interactions were identified. High-field NMR analysis of the GBFS/MKPC system indicated the potential formation of a potassium-aluminosilicate phase. This study demonstrates the need for further research on these binders, as both FA and GBFS are generally regarded as inert fillers within MKPC.

  11. Studying the Hydration of a Retarded Suspension of Ground Granulated Blast-Furnace Slag after Reactivation

    Directory of Open Access Journals (Sweden)

    Nick Schneider

    2016-11-01

    Full Text Available This article presents a combined use of a retarder (d-gluconic acid and an alkaline activator (sodium hydroxide in a binder system based on ground granulated blast-furnace slag. The properties of the retarder are extending the dormant hydration period and suppressing the generation of strength-giving phases. Different retarder concentrations between 0.25 and 1.00 wt.% regulate the intensity and the period of the retardation and also the characteristics of the strength development. The activator concentration of 30 and 50 wt.% regulates the overcoming of the dormant period and thereby the solution of the slag and hence the formation of the hydration products. The research objective is to produce a mineral binder system based on two separate liquid components. The highest concentration of retarder and activator generates the highest compressive strength and mass of hydration products—after 90 days of hydration a compressive strength of more than 50 N/mm2. The main phases are calcium silicate hydrate and hydrotalcite. Generally, the combination of retarder and activator shows a high potential in the performance increase of the hydration process.

  12. Reactivation of a Retarded Suspension of Ground Granulated Blast-Furnace Slag

    Directory of Open Access Journals (Sweden)

    Nick Schneider

    2016-03-01

    Full Text Available An effective retarded suspension of ground granulated blast-furnace slag (GGBFS needs a strong activator to reactivate the hydration. In this research study, sodium hydroxide (NaOH as an alkali activator in two different concentrations (30 and 50 wt.% was used to overcome the retardation and give the hardened GGBFS the reasonable strength. The study was carried out with a mixture of GGBFS, a solution of 1.0 wt.% d-gluconic acid (C6H12O7 as a retarder in the mixing water and a methyl cellulose as a stabilizer. The reactivation was executed after seven different periods (up to 28 days after the system was retarded. The following investigations were performed: slump test, measurement of ultrasonic (US velocity, compressive strength and gross density, thermogravimetry (TG and scanning electron microscopy (SEM. The analyses of the hardened samples were carried out seven, 28 and 90 days after the reactivation. The result of the study is an effective reactivation of a retarded suspension. In this case, the activator with 50 wt.% NaOH shows a very high performance. The setting time of the reactivated binders is much longer compared to the reference, but, in the longer term, the compressive strength and the progress of the hydration exceed the performance of the reference.

  13. A Binder of Phosphogypsum-Ground Granulated Blast Furnace Slag-Ordinary Portland Cement

    Institute of Scientific and Technical Information of China (English)

    HUANG Yun; LIN Zongshou

    2011-01-01

    A new hydraulic cementitious binder was developed by mainly utilizing industrial byproducts phosphogypsum (PG) and ground granulated blast furnace slag (GGBFS) with small addition of ordinary portland cement (OPC). The hydration process and microstructure were studied by X-ray diffraction (XRD)and scanning electronic microscopy (SEM). OPC hydrated first at early age to form primarily C-S-H gel, ettringite and calcium hydroxide (CH). GGBFS activated by CH and sulfate ions hydrated continuously at later age, producing more and more hydration products, C-S-H gel and ettringite. Thus the paste developed a denser microstructure and its strength increased. The 28 d compressive strength of the mixture of 50% PG, 46% GGBFS and 4% OPC exceeded 45 MPa. The setting time was faster and 3 d and 7 d strength were higher when the proportion of OPC increased. But the 28 d strength decreased when OPC exceeded 4% due to large amount of ettringite formed at late hydration age which damaged the microstructure.

  14. Determination of blast-induced ground vibration equations for rocks using mechanical and geological properties

    Institute of Scientific and Technical Information of China (English)

    Ranjan Kumar; Deepankar Choudhury; Kapilesh Bhargava

    2016-01-01

    In the recent decades, effects of blast loads on natural and man-made structures have gained considerable attention due to increase in threat from various man-made activities. Site-specific empirical relationships for calculation of blast-induced vibration parameters like peak particle velocity (PPV) and peak particle displacement (PPD) are commonly used for estimation of blast loads in design. However, these relation-ships are not able to consider the variation in rock parameters and uncertainty of in situ conditions. In this paper, a total of 1089 published blast data of various researchers in different rock sites have been collected and used to propose generalized empirical model for PPV by considering the effects of rock parameters like unit weight, rock quality designation (RQD), geological strength index (GSI), and uniaxial compressive strength (UCS). The proposed PPV model has a good correlation coefficient and hence it can be directly used in prediction of blast-induced vibrations in rocks. Standard errors and coefficient of correlations of the predicted blast-induced vibration parameters are obtained with respect to the observed field data. The proposed empirical model for PPV has also been compared with the empirical models available for blast vibrations predictions given by other researchers and found to be in good agreement with specific cases.

  15. Hydration Properties of Ground Granulated Blast-Furnace Slag (GGBS Under Different Hydration Environments

    Directory of Open Access Journals (Sweden)

    Shuhua LIU

    2017-02-01

    Full Text Available The hydration properties of various cementitious materials containing Ground Granulated Blast-furnace Slag (GGBS, two alkali-activated slag cements (AAS-1 and AAS-2 in which sodium silicate and sodium hydroxide act as alkaline activators respectively, supersulfated cement (SSC and slag Portland cement(PSC, are compared with ordinary Portland cement (OPC to investigate the effect of activating environment on the hydration properties in this study by determining the compressive strength of the pastes, the hydration heat of binders within 96 hours, and the hydration products at age of 28 days. The results show that C-S-H gels are the main hydrated products for all cementitious systems containing GGBS. Ca(OH2 is the hydration products of OPC and PSC paste. However, ettringite and gypsum crystals instead of Ca(OH2 are detected in SSC paste. Additionally, tobermorite, a crystalline C-S-H, and calcite are hydrated products in AAS-1. Tobermorite, cowlesite and calcite are hydrated products of AAS-2 as well. Based on strength results, AAS-1 paste exhibits the highest compressive strength followed by POC, PSC, SSC in order at all testing ages and AAS-2 give the lowest compressive strength except for the early age at 3 days, which is higher than SSC but still lower than PSC. From hydration heat analysis, alkalinity in the reaction solution is a vital factor influencing the initial hydration rate and the initial hydration rate from higher to lower is AAS-2, AAS-1, OPC, PSC and SSC. Although AAS possesses a faster reaction rate in the initial hours, cumulative hydration heat of AAS is comparably lower than that of OPC, but higher than those of PSC and SSC in turn, which indicates that the hydration heat of clinkers is much higher than that of slag.DOI: http://dx.doi.org/10.5755/j01.ms.23.1.14934

  16. Study of mass attenuation coefficients and effective atomic numbers of bismuth-ground granulated blast furnace slag concretes

    Science.gov (United States)

    Kumar, Sandeep; Singh, Sukhpal

    2016-05-01

    Five samples of Bismuth-Ground granulated blast furnace slag (Bi-GGBFS) concretes were prepared using composition (0.6 cement + x Bi2O3 + (0.4-x) GGBFS, x = 0.05, 0.10, 0.15, 0.20 and 0.25) by keeping constant water (W) cement (C) ratio. Mass attenuation coefficients (μm) of these prepared samples were calculated using a computer program winXCOM at different gamma ray energies, whereas effective atomic numbers (Zeff) is calculated using mathematical formulas. The radiation shielding properties of Bi-GGBFS concrete has been compared with standard radiation shielding concretes.

  17. The on-line electric vehicle wireless electric ground transportation systems

    CERN Document Server

    Cho, Dong

    2017-01-01

    This book details the design and technology of the on-line electric vehicle (OLEV) system and its enabling wireless power-transfer technology, the “shaped magnetic field in resonance” (SMFIR). The text shows how OLEV systems can achieve their three linked important goals: reduction of CO2 produced by ground transportation; improved energy efficiency of ground transportation; and contribution to the amelioration or prevention of climate change and global warming. SMFIR provides power to the OLEV by wireless transmission from underground cables using an alternating magnetic field and the reader learns how this is done. This cable network will in future be part of any local smart grid for energy supply and use thereby exploiting local and renewable energy generation to further its aims. In addition to the technical details involved with design and realization of a fleet of vehicles combined with extensive subsurface charging infrastructure, practical issues such as those involved with pedestrian safety are c...

  18. Curl-meter of Electrical Fields In The Ground.

    Science.gov (United States)

    Krylov, S. M.; Maibuk, Z.-Ju. Ja.; Nikiforova, N. N.

    A special instrument U curl-meter was designed and manufactured in the Institute of Physics of the Earth of RAS for measuring of variable electric fields during alternation of stressedly-deformed state in rock mass. The instrument consist the four-electrode unit and a circuit of analogue signal processing for separation of E U circulations or according to the StokesSs theorem, Curl E in absence of indirect sources. Four electrodes are laied out in rocks on angles of square and they are affixed by ring-type circuit to uninverting inputs of precision operational amplifiers. First input is connected to electrode N1, the second one is connected to N2 and so on. The independent inputs are grounded to a arbitrary point (the fifth electrode is SzeroT). The transmission factors of the circuit are set by resistors accurate to within 0.25 %. First and third, and also second and fourth outputs of the amplifiers are connected to the grad EX and grad EY calculation circuit (deduction circuits). So, if the vector components have different signs of both two EX values and two values EY, the gradient calculation circuit generates signal extremums. If in this case the signs inside pairs are identical , that means that the signal not- ring-type and it is absent on output (difference of the equal values with equal signs). The signals from outputs of the gradient calculations act into adding device for calculation of Curl E (circulation). Curl-meter differs by high security from clutters and from cues on any of inputs rather of "zero point" (ground) reacting only on a ring-type current, thus it is essential (on the order) the noise level and drift of operational amplifiers is moderated. Curl-meter works in a complex of measuring devices on Obninsk seismological polygon for study of behavior of superlow frequency of tectonic genesis electromagnetic emission. Through four inputs (electrode spacing 7x7 2, resistance between welding rods 0.8 - 1.1 kOm), manufactured from fine- dyspersated

  19. Influence of Carbonation on Fatigue of Concrete with High Volume of Ground Granulated Blast-furnace Slag

    Institute of Scientific and Technical Information of China (English)

    YOU Lushen; JIANG Linhua; CHU Hongqiang

    2015-01-01

    The effect of carbonation on fatigue performance of ground granulated blast-furnace slag concrete was investigated. Based on the static compression tests of carbonated GGBS-concrete, the correlation between carbonation depth and compressive strength was analyzed and an equation between carbonation depth and compressive strength was put forward. Meanwhile, fatigue S-N curves of various carbonation depths were fitted, and the influence of carbonation on fatigue life and strength was studied. Carbonation has a dual effect on the fatigue behavior of GGBS-concrete. A fatigue equation based on the depth of carbonation was established. Also, the probabilistic distribution of fatigue life of carbonated concrete at a given stress level was modeled by the two-parameter Weibull distribution.

  20. Studies on the corrosion resistance of reinforced steel in concrete with ground granulated blast-furnace slag--An overview.

    Science.gov (United States)

    Song, Ha-Won; Saraswathy, Velu

    2006-11-16

    The partial replacement of clinker, the main constituent of ordinary Portland cement by pozzolanic or latent hydraulic industrial by-products such as ground granulated blast furnace slag (GGBFS), effectively lowers the cost of cement by saving energy in the production process. It also reduces CO2 emissions from the cement plant and offers a low priced solution to the environmental problem of depositing industrial wastes. The utilization of GGBFS as partial replacement of Portland cement takes advantage of economic, technical and environmental benefits of this material. Recently offshore, coastal and marine concrete structures were constructed using GGBFS concrete because high volume of GGBFS can contribute to the reduction of chloride ingress. In this paper, the influence of using GGBFS in reinforced concrete structures from the durability aspects such as chloride ingress and corrosion resistance, long term durability, microstructure and porosity of GGBFS concrete has been reviewed and discussed.

  1. The radiation stability of ground granulated blast furnace slag/ordinary Portland cement grouts containing organic admixtures

    Energy Technology Data Exchange (ETDEWEB)

    Palmer, J.D.; Fairhall, G.A. [British Nuclear Fuels, Sellafield (United Kingdom)

    1993-12-31

    At the British Nuclear Fuels (BNFL) Sellafield reprocessing plant in the United Kingdom, cement grouts based on ground granulated blast-furnace slag (BFS) and ordinary Portland cement (OPC) are used extensively for immobilizing radioactive wastes. These grouts have excluded organic admixtures in order to reduce process complexity and uncertainties, regarding the performance of organic admixtures with BFS/OPC grouts, particularly under irradiation. This study has investigated the effects of sulfonated melamine formaldehyde and naphthalene condensates on grout properties. The results show grout settlement and strengths increase on addition of additives, with the additives remaining largely in the pore solution. Under irradiation the additives breakdown liberating hydrogen and carbon dioxide. Strength and product dimensions are unaffected by irradiation.

  2. An ANN-based approach to predict blast-induced ground vibration of Gol-E-Gohar iron ore mine, Iran

    Institute of Scientific and Technical Information of China (English)

    Mahdi Saadat; Manoj Khandelwal; M. Monjezi

    2014-01-01

    Blast-induced ground vibration is one of the inevitable outcomes of blasting in mining projects and may cause substantial damage to rock mass as well as nearby structures and human beings. In this paper, an attempt has been made to present an application of artificial neural network (ANN) to predict the blast-induced ground vibration of the Gol-E-Gohar (GEG) iron mine, Iran. A four-layer feed-forward back propagation multi-layer perceptron (MLP) was used and trained with Levenberg-Marquardt algorithm. To construct ANN models, the maximum charge per delay, distance from blasting face to monitoring point, stemming and hole depth were taken as inputs, whereas peak particle velocity (PPV) was considered as an output parameter. A database consisting of 69 data sets recorded at strategic and vulnerable locations of GEG iron mine was used to train and test the generalization capability of ANN models. Coefficient of determination (R2) and mean square error (MSE) were chosen as the indicators of the performance of the networks. A network with architecture 4-11-5-1 and R2 of 0.957 and MSE of 0.000722 was found to be optimum. To demonstrate the supremacy of ANN approach, the same 69 data sets were used for the prediction of PPV with four common empirical models as well as multiple linear regression (MLR) analysis. The results revealed that the proposed ANN approach performs better than empirical and MLR models.

  3. An ANN-based approach to predict blast-induced ground vibration of Gol-E-Gohar iron ore mine, Iran

    Directory of Open Access Journals (Sweden)

    Mahdi Saadat

    2014-02-01

    Full Text Available Blast-induced ground vibration is one of the inevitable outcomes of blasting in mining projects and may cause substantial damage to rock mass as well as nearby structures and human beings. In this paper, an attempt has been made to present an application of artificial neural network (ANN to predict the blast-induced ground vibration of the Gol-E-Gohar (GEG iron mine, Iran. A four-layer feed-forward back propagation multi-layer perceptron (MLP was used and trained with Levenberg–Marquardt algorithm. To construct ANN models, the maximum charge per delay, distance from blasting face to monitoring point, stemming and hole depth were taken as inputs, whereas peak particle velocity (PPV was considered as an output parameter. A database consisting of 69 data sets recorded at strategic and vulnerable locations of GEG iron mine was used to train and test the generalization capability of ANN models. Coefficient of determination (R2 and mean square error (MSE were chosen as the indicators of the performance of the networks. A network with architecture 4-11-5-1 and R2 of 0.957 and MSE of 0.000722 was found to be optimum. To demonstrate the supremacy of ANN approach, the same 69 data sets were used for the prediction of PPV with four common empirical models as well as multiple linear regression (MLR analysis. The results revealed that the proposed ANN approach performs better than empirical and MLR models.

  4. Monitoring of ground water aquifer by electrical prospecting; Denki tansaho ni yoru chikasui monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Ushijima, K. [Kyushu University, Fukuoka (Japan)] [Faculty of Engineering (Japan)

    1997-12-01

    This paper describes three case studies for monitoring ground water aquifers by electrical prospecting. An example in the Hofu plain, Yamaguchi Prefecture is presented, where the ground water environment has been monitored for more than 30 years from the viewpoint of hydrology. Then, transition from the fresh ground water to sea water is evaluated by a sharp boundary as salt-water wedges through the field survey in a coastal area of a large city for a short term using vertical electrical prospecting. Moreover, streaming potential measurements are described to grasp the real-time behavior of ground water flow. From the long-term monitoring of ground water aquifer, it was found that the variation of ground water streaming can be evaluated by monitoring the long-term successive change in the resistivity of ground water aquifer. From the vertical electrical prospecting, water quality can be immediately judged through data analysis. From the results of streaming potential measurements and vertical electrical prospecting using Schlumberger method, streaming behavior of ground water in the area of spring water source can be estimated by determining three-dimensional resistivity structure. 17 refs., 15 figs.

  5. The Improvement and Data Acquisition Systems on Electrical Systems and Grounding Networks in NSRRC

    CERN Document Server

    Liu, Yung-Hui; Chen June Rong; Lin, Yu-Chih; Tsai, Zong-Da

    2005-01-01

    The purpose of this paper is to declare the improvement on electrical and grounding systems in NSRRC. In electrical power system, an Automated Voltage Regulator (AVR) was established to RF system in 2003. The variation of voltage supply from Taiwan Power Company (TPC) is reduced from 3% to 0.2% through the AVR system. And a Supervisory Control and Data Acquisition (SCADA) system was also setup to monitoring the electrical power conditions in each power station. After the high precision grounding systems were constructed in 2004, the stability of beam line was raised. For comprehending the grounding current and noise control, a grounding monitoring system with 32 channels was built in the storage ring. The grounding currents of 4 kickers, one septum and grounding bus are on-line acquisition. Two Electromagnetic Field (EMF) apparatuses were also installed to collect electrical and magnetic fields in the R1 section. It was observed that the electromagnetic field was correlated to grounding currents in certain lo...

  6. Modeling blast waves, gas and particles dispersion in urban and hilly ground areas.

    Science.gov (United States)

    Hank, S; Saurel, R; Le Métayer, O; Lapébie, E

    2014-09-15

    The numerical simulation of shock and blast waves as well as particles dispersion in highly heterogeneous media such as cities, urban places, industrial plants and part of countries is addressed. Examples of phenomena under study are chemical gas products dispersion from damaged vessels, gas dispersion in urban places under explosion conditions, shock wave propagation in urban environment. A three-dimensional simulation multiphase flow code (HI2LO) is developed in this aim. To simplify the consideration of complex geometries, a heterogeneous discrete formulation is developed. When dealing with large scale domains, such as countries, the topography is considered with the help of elevation data. Meteorological conditions are also considered, in particular regarding complex temperature and wind profiles. Heat and mass transfers on sub-scale objects, such as buildings, trees and other obstacles are considered as well. Particles motion is addressed through a new turbulence model involving a single parameter to describe accurately plumes. Validations against experiments in basic situations are presented as well as examples of industrial and environmental computations.

  7. Properties of Concrete Incorporating Bed Ash from Circulating Fluidized Bed Combustion and Ground Granulates Blast-furnace Slag

    Institute of Scientific and Technical Information of China (English)

    CHENG An; HSU Hui-Mi; CHAO Sao-Jeng

    2011-01-01

    The properties of concrete incorporating circulating fluidized bed combustion (CFBC) bed ash and ground granulates blast-furnace slag (GGBS) were studied. Compressive strength,drying shrinkage, mercury intrusion porosimetry (MIP), scanning electronic microscopy (SEM), and X-ray diffraction (XRD) of concrete samples containing CFBC bed ash and GGBS were used. This work used initial surface absorption test (ISAT) and rapid chloride penetration test (RCPT) on concrete to measure the absorption and the ability of concrete to resist chloride ion characteristics for different concrete samples containing CFBC bed ash and GGBS. Open circuit potential (OCP), direct current polarization resistance were obtained to evaluate rebar corrosion. The CFBC bed ash was X-ray amorphous and consist of SiO2, A12O3 and CaO compounds. As the replacement of CFBC for sand increases, the rate of initial surface absorption (ISA) increases but compressive strength decreases.When the content of CFBC bed ash replacement for sand maintains constant, the replacement of GGBS for cement increases, compressive strength increases but the rate of ISA decreases. Chloride and corrosion resistance of rebar significantly improve by utilizing a proper amount of CFBC bed ash and GGBS in concrete.

  8. Recycling ground granulated blast furnace slag as cold bonded artificial aggregate partially used in self-compacting concrete.

    Science.gov (United States)

    Gesoğlu, Mehmet; Güneyisi, Erhan; Mahmood, Swara Fuad; Öz, Hatice Öznur; Mermerdaş, Kasım

    2012-10-15

    Ground granulated blast furnace slag (GGBFS), a by-product from iron industry, was recycled as artificial coarse aggregate through cold bonding pelletization process. The artificial slag aggregates (ASA) replaced partially the natural coarse aggregates in production of self-compacting concrete (SCC). Moreover, as being one of the most widely used mineral admixtures in concrete industry, fly ash (FA) was incorporated as a part of total binder content to impart desired fluidity to SCCs. A total of six concrete mixtures having various ASA replacement levels (0%, 20%, 40%, 60%, and 100%) were designed with a water-to-binder (w/b) ratio of 0.32. Fresh properties of self-compacting concretes (SCC) were observed through slump flow time, flow diameter, V-funnel flow time, and L-box filling height ratio. Compressive strength of hardened SCCs was also determined at 28 days of curing. It was observed that increasing the replacement level of ASA resulted in decrease in the amount of superplasticizer to achieve a constant slump flow diameter. Moreover, passing ability and viscosity of SCC's enhanced with increasing the amount of ASA in the concrete. The maximum compressive strength was achieved for the SCC having 60% ASA replacement.

  9. Strength development characteristics of concrete produced with blended cement using ground granulated blast furnace slag (GGBS) under various curing conditions

    Indian Academy of Sciences (India)

    SHAHAB SAMAD; ATTAULLAH SHAH; MUKESH C LIMBACHIYA

    2017-07-01

    To reduce the embodied carbon dioxide of structural concrete, Portland cement (PC) in concrete can be partially replaced with ground granulated blast furnace slag (GGBS). In this research effect of partial replacement of cement with GGBS on strength development of concrete and cured under summer and wintercuring environments is established. Three levels of cement substitution i.e., 30%, 40% and 50% have been selected. Early-age strength of GGBS concrete is lower than the normal PC concrete which limits its use in the fast-track construction and post-tensioned beams which are subjected to high early loads. The strength gainunder winter curing condition was observed as slower. By keeping the water cement ratio low as 0.35, concrete containing GGBS up to 50% can achieve high early-age strength. GGBS concrete gains more strength than the PC concrete after the age of 28 day till 56 day. The mechanical properties of blended concrete for various levels of cement replacement have been observed as higher than control concrete mix having no GGBS.

  10. Evaluation of Horizontal Electric Field Under Different Lightning Current Models by Perfect Ground Assumption

    Institute of Scientific and Technical Information of China (English)

    LIANG Jianfeng; LI Yanming

    2012-01-01

    Lightning electromagnetics can affect the reliability of the power system or communication system.Therefore,evaluation of electromagnetic fields generated by lightning return stroke is indispensable.Arnold sommerfeld proposed a model to calculate the electromagnetic field,but it involved the time-consuming sommerfeld integral.However,perfect conductor ground assumption can account for fast calculation,thus this paper reviews the perfect ground equation for evaluation of lightning electromagnetic fields,presents three engineering lightning return stroke models,and calculates the horizontal electric field caused by three lightning return stroke models.According to the results,the amplitude of lightning return stroke has a strong impact on horizontal electric fields,and the steepness of lightning return stroke influences the horizontal electric fields.Moreover,the perfect ground method is faster than the sommerfeld integral method.

  11. Study of some health physics parameters of bismuth-ground granulated blast furnace slag shielding concretes

    Science.gov (United States)

    Kumar, Sandeep; Singh, Sukhpal

    2016-05-01

    The Bismuth-ground granulated blastfurnace slang (Bi-GGBFS) concrete samples were prepared. The weight percentage of different elements present inBi-GGBFS Shielding concretewas evaluated by Energy Dispersive X-ray Microanalysis (EDX). The exposure rate and absorbed dose rate characteristics were calculated theoretically for radioactive sources namely 241Am and 137Cs. Our calculations reveal that the Bi-GGBFS concretes are effective in shielding material for gamma radiations.

  12. Electric Signals on and under the Ground Surface Induced by Seismic Waves

    Directory of Open Access Journals (Sweden)

    Akihiro Takeuchi

    2012-01-01

    Full Text Available We constructed three observation sites in northeastern Japan (Honjo, Kyowa, and Sennan with condenser-type large plate electrodes (4 × 4 m2 as sensors supported 4 m above the ground and with pairs of reference electrodes buried vertically at 0.5 m and 2.5 m depth (with a ground velocity sensor at Sennan only. Electrical signals of an earthquake (M6.3 in northeastern Japan were detected simultaneously with seismic waves. Their waveforms were damped oscillations, with greatly differing signal amplitudes among sites. Good positive correlation was found between the amplitudes of signals detected by all electrodes. We propose a signal generation model: seismic acceleration vertically shook pore water in the topsoil, generating the vertical streaming potential between the upper unsaturated water zone and the lower saturated water zone. Maximum electric earth potential difference was observed when one electrode was in the saturated water zone, and the other was within the unsaturated water zone, but not when the electrodes were in the saturated water zone. The streaming potential formed a charge on the ground surface, generating a vertical atmospheric electric field. The large plate electrode detected electric signals related to electric potential differences between the electrode and the ground surface.

  13. Properties of mortars made by uncalcined FGD gypsum-fly ash-ground granulated blast furnace slag composite binder.

    Science.gov (United States)

    Zhong, Shiyun; Ni, Kun; Li, Jinmei

    2012-07-01

    A series of novel mortars were developed from composite binder of uncalcined FGD gypsum, fly ash (FA) and ground granulated blast furnace slag (GGBFS) for the good utilization of flue gas desulphurization (FGD) gypsum. At a fixed ratio (20%) of GGBFS to the composite binder, keeping consistency of the mortar between 9.5 and 10.0 cm, the properties of the composite mortar were studied. The results show that higher water/binder (W/B) is required to keep the consistency when increasing the percentage of FGD gypsum. No obvious influences of the W/B and content of FGD gypsum on the bleeding of paste were observed which keeps lower than 2% under all experimental conditions tried. The highest compressive and flexural strengths (ratio is 20% FGD gypsum, 20% GGBFS and 60% FA) are 22.6 and 4.3 MPa at 28 days, respectively. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) results indicate that massive ettringite crystals and C-S-H gels exist in the hydration products. At 90 days the mortars with FGD gypsum is dramatically smaller drying shrinkage (563-938 micro strain) than that without FGD gypsum (about 2250 micro strain). The release of the SO(4)(2-) from the mortar was analyzed, indicating that the dissolution of sulfate increases with FGD gypsum. The concentration of SO(4)(2-) releasing from the mortar with 10% FGD gypsum is almost equal to that obtained from the mortar without FGD gypsum. The release of SO(4)(2-) from the mortar with 20% FGD gypsum is 9200 mg·m(-2), which is lower than that from the mortar with 95% cement clinker and 5% FGD gypsum.

  14. Blasting Vibration Generated by Breaking-Blasting Large Barriers with EBBLB

    OpenAIRE

    Wang Zhen-xiong; Gu Wen-bin; Liang Ting; Liu Jian-qing; Xu Jing-lin; Liu Xin

    2016-01-01

    Equipment for breaking and blasting large barriers (EBBLB) is new break-blast equipment, which inevitably induces ground vibration and may cause substantial damage to rock mass and nearby structures as well as human beings. The ground vibration induced by break-blast is one of the inevitable outcomes. By monitoring vibration at measuring points at different distances from blasting center, time history curve of vibrating velocity can be obtained; it can be drawn that blasting seismic waves are...

  15. Theoretical investigation of boundary contours of ground-state atoms in uniform electric fields

    Science.gov (United States)

    Shi, Hua; Zhao, Dong-Xia; Yang, Zhong-Zhi

    2015-12-01

    The boundary contours were investigated for first 54 ground-state atoms of the periodic table when they are in uniform electric fields of strengths 106, 107 and 108 V/m. The atomic characteristic boundary model in combination with an ab-initio method was employed. Some regularities of the deformation of atoms, ΔR, in above electric fields are revealed. Furthermore, atomic polarisabilities of the first 54 elements of the periodic table are shown to correlate strongly with the mean variation rate of atomic radial size divided by the strength of the electric field F, ?, which provides a predictive method of calculating atomic polarisabilities of 54 atoms.

  16. 30 CFR 75.1323 - Blasting circuits.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Blasting circuits. 75.1323 Section 75.1323... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1323 Blasting circuits. (a) Blasting circuits shall be protected from sources of stray electric current. (b) Detonators made...

  17. 30 CFR 56.6312 - Secondary blasting.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Secondary blasting. 56.6312 Section 56.6312... Secondary blasting. Secondary blasts fired at the same time in the same work area shall be initiated from one source. Electric Blasting...

  18. Hydrogeological characterisation using cross-borehole ground penetration radar and electrical resistivity tomography

    DEFF Research Database (Denmark)

    Zibar, Majken Caroline Looms

    2007-01-01

    . The methods provided estimates of soil moisture content and electrical resistivity variations among 12 m deep boreholes located 5 – 7 m apart. The moisture content change following natural precipitation was observed to be practically negligible, providing minimal information to constrain the dynamic...... was characterized by ~30 m thick unsaturated zone consisting mainly of sands of varying coarseness. Following an instrumentation of 16 boreholes two geophysical methods (cross-borehole ground penetrating radar and electrical resistivity tomography) were applied during natural precipitation and forced infiltration...... properties of the subsurface. On the other hand, volumetric moisture content variations of up to 5% were observed during a 20-day long forced infiltration experiment. The cross-borehole electrical resistance tomography and ground penetrating radar data collected during this experiment were subsequently...

  19. Hydrogeological characterisation using cross-borehole ground penetration radar and electrical resistivity tomography

    DEFF Research Database (Denmark)

    Zibar, Majken Caroline Looms

    2007-01-01

    . The methods provided estimates of soil moisture content and electrical resistivity variations among 12 m deep boreholes located 5 – 7 m apart. The moisture content change following natural precipitation was observed to be practically negligible, providing minimal information to constrain the dynamic...... was characterized by ~30 m thick unsaturated zone consisting mainly of sands of varying coarseness. Following an instrumentation of 16 boreholes two geophysical methods (cross-borehole ground penetrating radar and electrical resistivity tomography) were applied during natural precipitation and forced infiltration...... properties of the subsurface. On the other hand, volumetric moisture content variations of up to 5% were observed during a 20-day long forced infiltration experiment. The cross-borehole electrical resistance tomography and ground penetrating radar data collected during this experiment were subsequently...

  20. Strength, leachability and microstructure characterisation of Na2SiO3-activated ground granulated blast-furnace slag solidified MSWI fly ash.

    Science.gov (United States)

    Zhang, Dajie; Liu, Wenshi; Hou, Haobo; He, Xinghua

    2007-10-01

    The chemical composition and the leachability of heavy metals in municipal solid waste incinerator (MSWI) fly ash were measured and analysed. For the leachability of unstabilized MSWI fly ash it was found that the concentrations of Pb and Cr exceeded the leaching toxicity standard. Cementitious solidification of the MSWI fly ash by Na2SiO3-activated ground granulated blast-furnace slag (NS) was investigated. Results show that all solidified MSWI fly ash can meet the landfill standards after 28 days of curing. The heavy metals were immobilized within the hydration products such as C-S-H gel and ettringite through physical encapsulation, substitution, precipitation or adsorption mechanisms.

  1. ANALYSIS OF ELECTROPHYSICAL CHARACTERISTICS OF GROUNDS IN THE VICINITY ELECTRICAL SUBSTATION OF UKRAINE

    Directory of Open Access Journals (Sweden)

    D.G. Koliushko

    2015-06-01

    Full Text Available Purpose. Definition of the direction for further research to improve accuracy of the calculation of rated parameters of ground grids based on the analysis of statistical databases of electro-physical characteristics of the soil. Methodology. To solve this problem we compiled the statistical base of soil of Ukraine in the location of electrical substation, we performed the statistical analysis for the number of layers of geoelectric structure, and electrical characteristics. In the experiments implemented the comparing of accuracy calculation of the most typical three-layer soil in the Ukraine, by the new three-layer model of ground grids and the equivalent two-layer model, which used previously. Results. On the results of analysis the ranges of the electrical resistivity and statistical distribution for electro-physical characteristics of the soil are determined. The resulting distributions allow to develop criteria for instruments, installations and means of interpretation during the sounding of soil, as well as the requirements for mathematical models of ground grids. It was found that the most typical for places of locations the electrical substations in Ukraine are three-layer geoelectric structures. In the paper the statistical distribution for three-layer soil by type (Q, K, H, A are described. The results of numerical experiments show that the use of methods to simplify of the multilayers soil does not allow the calculation of grounding grids with high accuracy. In the work recommendations for applicability the method equivalenting depending on the type of geoelectric structure are developed. Originality. For the first time, we obtained the statistical distribution of stratification of the soil in the location of power plant in Ukraine, determined the accuracy of the method to simplify a multi-layer soil in determining the rated parameters of grounding grids. In the paper the necessity to develop a mathematical model of the grounding

  2. Strong ground motion generated by controlled blasting experiments and mining induced seismic events recorded underground at deep level mines in South Africa

    Science.gov (United States)

    Milev, A.; Selllers, E.; Skorpen, L.; Scheepers, L.; Murphy, S.; Spottiswoode, S. M.

    2011-12-01

    A number of simulated rockbursts were conducted underground at deep level gold mines in South Africa in order to estimate the rock mass response when subjected to strong ground motion. The rockbursts were simulated by means of large blasts detonated in solid rock close to the sidewall of a tunnel. The simulated rockbursts involved the design of the seismic source, seismic observations in the near and far field, high-speed video filming, a study of rock mass conditions such as fractures, joints, rock strength etc. Knowledge of the site conditions before and after the simulated rockbursts was also gained. The numerical models used in the design of the simulated rockbursts were calibrated by small blasts taking place at each experimental site. A dense array of shock type accelerometers was installed along the blasting wall to monitor the attenuation of the strong ground motion as a function of the distance from the source. The attenuation of peak particle velocities, was found to be proportional to R^-1.7. Special investigations were carried out to evaluate the mechanism and the magnitude of damage, as well as the support behaviour under excessive dynamic loading. The strong ground motion generated by mining induced seismic events was studied, as part of this work, not only to characterize the rock mass response, but also to estimate the site effect on the surface of the underground excavations. A stand-alone instrument especially designed for recording strong ground motions was used to create a large database of peak particle velocities measured on stope hangingwalls. A total number of 58 sites located in stopes where the Carbon Leader Reef, Ventersdorp Contact Reef, Vaal Reef and Basal Reef are mined, were monitored. The peak particle velocities were measured at the surface of the excavations to identify the effect of the free surface and the fractures surrounding the underground mining. Based on these measurements the generally accepted velocity criterion of 3 m

  3. Repulsion forces of superplasticizers on ground granulated blast furnace slag in alkaline media, from AFM measurements to rheological properties

    Directory of Open Access Journals (Sweden)

    Palacios, M.

    2012-12-01

    Full Text Available The electrostatic and steric repulsion induced by different superplasticizers on ground granulated blast furnace slag in alkaline media have been studied. The superplasticizers were sulfonated naphthalene, sulfonated melamine, vinyl copolymer, and polycarboxylate- based admixtures. With these superplasticizers the slag suspensions had negative zeta potentials, ranging from -3 to -10 mV. For the first time the adsorbed layer thicknesses for superplasticizers on slag using colloidal probe atomic force microscopy has been measured. To model the interparticle force interactions an effective Hamaker constant was computed from dielectric properties measured on a dense slag sample produced by spark plasma sintering. The obtained results conclude that the dispersion mechanism for all the superplasticizers studied in the present work is mainly dominated by the steric repulsion. Results were then used in a yield stress model, YODEL, to predict the yield stress with and without the superplasticizers. Predictions of the yield stress agreed well with experimental results.

    En este trabajo se ha estudiado la repulsión electrostática y estérica inducida por diferentes aditivos superplastificantes en sistemas de escoria de horno alto en medios alcalinos. Se han estudiado aditivos superplastificantes basados en naftaleno, melamina, copolímeros vinílicos y basados en policarboxilato. Estos aditivos inducen en la escoria un potencial zeta negativo, entre -3 y -10 mV. Por primera vez, se ha determinado el grosor de la capa de aditivo adsorbido sobre la escoria mediante microscopía de fuerzas atómicas (AFM. Para modelizar las fuerzas de interacción entre partículas, se ha determinado la constante efectiva de Hamaker de la escoria a partir de las propiedades dieléctricas de una muestra de escoria obtenida mediante sinterización spark plasma sintering. Los resultados obtenidos concluyen que el mecanismo de dispersión de los superplastificantes

  4. Rheology and zeta potential of cement pastes containing calcined silt and ground granulated blast-furnace slag

    Directory of Open Access Journals (Sweden)

    Safi, B.

    2011-09-01

    Full Text Available This study aimed to analyse the re-use of dam silt as a supplementary binder for self-compacting concrete (SCC. When burnt, silt becomes more reactive because the kaolin it contains is converted into metakaolin. Portland cement, calcined or burnt silt and ground granulated blast furnace slag were used in this research. Cement pastes were prepared with blends containing two or three of these materials. The replacement ratio for burnt silt in both cases was 10 % and 20 % by cement weight and the ratio for the slag was a constant 30 % by weight of the blend. Rheological and zeta potential tests were conducted to evaluate paste electrokinetics and rheological behaviour. The findings showed that burnt silt is apt for use as an addition to cement for SCC manufacture.

    En el presente trabajo se ha analizado la posibilidad de utilizar los lodos procedentes de embalses como adición en la fabricación del hormigón autocompactante (HAC. Con la calcinación, estos materiales se vuelven más reactivos debido a la transformación en metacaolín, del caolín que forma parte de su composición. Las materias primas empleadas en esta investigación son: cemento Pórtland, lodos de embalse calcinados y escorias granuladas de horno alto. Se prepararon pastas de cemento con mezclas que contenían dos o tres de estos materiales. El porcentaje de reemplazo de los lodos calcinados osciló entre el 10 y el 20 % en peso del cemento, mientras que el de la escoria fue del 30 % en peso de la mezcla. Se llevaron a cabo ensayos reológicos y de potencial zeta para evaluar el comportamiento electrocinético y reológico de las distintas pastas. De acuerdo con los resultados obtenidos, una vez calcinados, los lodos de embalse son aprovechables como adición al cemento con destino a la preparación de HAC.

  5. 30 CFR 56.6605 - Isolation of blasting circuits.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Isolation of blasting circuits. 56.6605 Section... Extraneous Electricity § 56.6605 Isolation of blasting circuits. Lead wires and blasting lines shall be... sources of stray or static electricity. Blasting circuits shall be protected from any contact...

  6. Characterization of Vacuum Facility Background Gas Through Simulation and Considerations for Electric Propulsion Ground Testing

    Science.gov (United States)

    Yim, John T.; Burt, Jonathan M.

    2015-01-01

    The background gas in a vacuum facility for electric propulsion ground testing is examined in detail through a series of cold flow simulations using a direct simulation Monte Carlo (DSMC) code. The focus here is on the background gas itself, its structure and characteristics, rather than assessing its interaction and impact on thruster operation. The background gas, which is often incorrectly characterized as uniform, is found to have a notable velocity within a test facility. The gas velocity has an impact on the proper measurement of pressure and the calculation of ingestion flux to a thruster. There are also considerations for best practices for tests that involve the introduction of supplemental gas flows to artificially increase the background pressure. All of these effects need to be accounted for to properly characterize the operation of electric propulsion thrusters across different ground test vacuum facilities.

  7. Low Power Ground-Based Laser Illumination for Electric Propulsion Applications

    Science.gov (United States)

    Lapointe, Michael R.; Oleson, Steven R.

    1994-01-01

    A preliminary evaluation of low power, ground-based laser powered electric propulsion systems is presented. A review of available and near-term laser, photovoltaic, and adaptive optic systems indicates that approximately 5-kW of ground-based laser power can be delivered at an equivalent one-sun intensity to an orbit of approximately 2000 km. Laser illumination at the proper wavelength can double photovoltaic array conversion efficiencies compared to efficiencies obtained with solar illumination at the same intensity, allowing a reduction in array mass. The reduced array mass allows extra propellant to be carried with no penalty in total spacecraft mass. The extra propellant mass can extend the satellite life in orbit, allowing additional revenue to be generated. A trade study using realistic cost estimates and conservative ground station viewing capability was performed to estimate the number of communication satellites which must be illuminated to make a proliferated system of laser ground stations economically attractive. The required number of satellites is typically below that of proposed communication satellite constellations, indicating that low power ground-based laser beaming may be commercially viable. However, near-term advances in low specific mass solar arrays and high energy density batteries for LEO applications would render the ground-based laser system impracticable.

  8. Determining the Forces Generated by the Contact of an Electrically-Operated Vehicle with the Ground

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In this paper we analyse the motion of an electric vehicle,when there is only the pure rolling of the wheels on the ground.The equations of holonomic and non-holonomic constraints have been rendered explicitly obtaining 27 equations algebraic-differential system with the same number of unknowns.Besides,this system supplies a model to calculate the bonding reaction forces.

  9. Settlement process of radioactive dust to the ground inferred from the atmospheric electric field measurement

    Directory of Open Access Journals (Sweden)

    M. Yamauchi

    2012-01-01

    Full Text Available Radioactive materials from the accident at Fukushima Dai-ichi nuclear power plant (FNPP in March 2011 spread over a large area, increasing the atmospheric electric conductivity by their ionizing effect, and reducing the vertical (downward component of the DC electric field near the ground, or potential gradient (PG. PG data at Kakioka, 150 km away from the FNPP, showed independent changes compared to the radiation dose rate, and a comparison of these data revealed the local dynamics of the radioactive dust.

    (1 The initial drop of the PG to almost zero during 14–15 March is most likely due to radioactive dust suspended in the air near the ground during cloudy weather. (2 An episode of PG increase to more than 50 V m−1 on 16 March is most likely due to the re-suspension of the radioactive dust from the surface and subsequent removal from Kakioka by the strong wind from the non-contaminated area. (3 Low but finite values of the PG during 16–20 March most likely reflect a reduced amount of radioactive material near the ground after the above wind transported away the majority of the suspended radioactive dust. (4 Very low values of the PG after substantial rain on 20–22 March most likely reflect settlement of the radioactive material by rain-induced fallout. (5 Temporal recovery of daily variations from the end of March to the middle of April with low nighttime fair-weather baseline PG most likely reflects re-suspension of the radioactive dust into the air from the ground and trees, and subsequent transport to the other region or fallout to the ground until late April. (6 Weakening of the daily variation and gradual recovery of the nighttime fair-weather baseline after mid-April suggests a complete settlement of the radioactive material to the ground with partial migration to the subsurface.

  10. Settlement process of radioactive dust to the ground inferred from the atmospheric electric field measurement

    Energy Technology Data Exchange (ETDEWEB)

    Yamauchi, M. [Swedish Institute of Space Physics, Kiruna (Sweden); Takeda, M. [Kyoto Univ. (Japan). Data Analysis Center for Geomagnetism and Space Magnetism; Makino, M.; Miyagi, I. [National Institute of Advanced Industrial Science and Technology, Tsukuba (Japan); Owada, T. [Japan Meteorological Agency, Ishioka (Japan). Kakioka Magnetic Observatory

    2012-07-01

    Radioactive materials from the accident at Fukushima Dai-ichi nuclear power plant (FNPP) in March 2011 spread over a large area, increasing the atmospheric electric conductivity by their ionizing effect, and reducing the vertical (downward) component of the DC electric field near the ground, or potential gradient (PG). PG data at Kakioka, 150 km away from the FNPP, showed independent changes compared to the radiation dose rate, and a comparison of these data revealed the local dynamics of the radioactive dust. (1) The initial drop of the PG to almost zero during 14-15 March is most likely due to radioactive dust suspended in the air near the ground during cloudy weather. (2) An episode of PG increase to more than 50Vm{sup -1} on 16 March is most likely due to the re-suspension of the radioactive dust from the surface and subsequent removal from Kakioka by the strong wind from the non-contaminated area. (3) Low but finite values of the PG during 16-20 March most likely reflect a reduced amount of radioactive material near the ground after the above wind transported away the majority of the suspended radioactive dust. (4) Very low values of the PG after substantial rain on 20-22 March most likely reflect settlement of the radioactive material by rain-induced fallout. (5) Temporal recovery of daily variations from the end of March to the middle of April with low nighttime fair-weather baseline PG most likely reflects re-suspension of the radioactive dust into the air from the ground and trees, and subsequent transport to the other region or fallout to the ground until late April. (6) Weakening of the daily variation and gradual recovery of the nighttime fair-weather baseline after mid-April suggests a complete settlement of the radioactive material to the ground with partial migration to the subsurface. (orig.)

  11. Settlement process of radioactive dust to the ground inferred from the atmospheric electric field measurement

    Science.gov (United States)

    Yamauchi, M.; Takeda, M.; Makino, M.; Owada, T.; Miyagi, I.

    2012-01-01

    Radioactive materials from the accident at Fukushima Dai-ichi nuclear power plant (FNPP) in March 2011 spread over a large area, increasing the atmospheric electric conductivity by their ionizing effect, and reducing the vertical (downward) component of the DC electric field near the ground, or potential gradient (PG). PG data at Kakioka, 150 km away from the FNPP, showed independent changes compared to the radiation dose rate, and a comparison of these data revealed the local dynamics of the radioactive dust. (1) The initial drop of the PG to almost zero during 14-15 March is most likely due to radioactive dust suspended in the air near the ground during cloudy weather. (2) An episode of PG increase to more than 50 V m-1 on 16 March is most likely due to the re-suspension of the radioactive dust from the surface and subsequent removal from Kakioka by the strong wind from the non-contaminated area. (3) Low but finite values of the PG during 16-20 March most likely reflect a reduced amount of radioactive material near the ground after the above wind transported away the majority of the suspended radioactive dust. (4) Very low values of the PG after substantial rain on 20-22 March most likely reflect settlement of the radioactive material by rain-induced fallout. (5) Temporal recovery of daily variations from the end of March to the middle of April with low nighttime fair-weather baseline PG most likely reflects re-suspension of the radioactive dust into the air from the ground and trees, and subsequent transport to the other region or fallout to the ground until late April. (6) Weakening of the daily variation and gradual recovery of the nighttime fair-weather baseline after mid-April suggests a complete settlement of the radioactive material to the ground with partial migration to the subsurface.

  12. Institutional Grounds of State Regulation of Interrelation of Subjects of the Electric Energy Market

    Directory of Open Access Journals (Sweden)

    Koliesnichenko Anastasiia S.

    2014-03-01

    Full Text Available The article improves the theoretical and mathematical mechanism in order to put in order institutional grounds of state regulation of interrelations that appear between subjects of the energy market in the process of electric energy trade. The article establishes structural and logical links between institutional factors of economic development and those functions of the state, which the state regulation of interrelations of subjects of the electric energy market is based upon. Based on the evolution approach the article analyses institutional instruments of state regulation of interrelation of subjects of the electric energy market, which takes into account specific features of its operation, specific conditions of development and creates a scientific and methodical basis for formation of concepts, strategies and programmes of development of the market of electric energy at the state level. The article considers and offers ways of improvement of the regulatory and legal provision of the process of state regulation of inter-subject relations of participants of the electric energy market with the aim of increase of scientific justification of draft laws and taking into consideration urgent problems when improving and developing regulatory and legal acts.

  13. Ground water contamination by electrical prospecting; Denki tansaho ni yoru chikasui osen chosa

    Energy Technology Data Exchange (ETDEWEB)

    Irie, S.; Fujii, Y.; Sakaguchi, S.; Ushijima, K. [Kyushu University, Fukuoka (Japan). Faculty of Engineering

    1996-05-01

    A report is made about the result of vertical electric sounding conducted in the MK district, Fukuoka City, where Kyushu University is about to move. As for the method of electrical prospecting, in consideration of the need for probing a depth of 50m at the shallowest, vertical electrical sounding with a Schlumberger array of electrodes was employed. Measurements were made for 57 locations on the planar ground, the interval between electrodes gradually increased from 1 to 200m. In the 2D structure model analysis, a 2D inversion program was utilized in the ABIC minimization method. Also investigated were the relationship of electric prospecting and the geology, geological conditions, water level in the well, water quality, salt water, and pore rate from the previously-conducted investigative boring. As the result, it was estimated that the boundary between the first and second layers detected by electric prospecting reflected the level of underground water and that the boundary between the second and third layers reflected the portion where the N-value sharply increases. 4 refs., 8 figs.

  14. Strength Development and Hydration Behavior of Self-Activation of Commercial Ground Granulated Blast-Furnace Slag Mixed with Purified Water

    Directory of Open Access Journals (Sweden)

    Hyeoneun Park

    2016-03-01

    Full Text Available In this study, ground granulated blast-furnace slag (GGBFS samples from Singapore, Korea, and the United Arab Emirates were hydrated with purified water to estimate the cementing capabilities without activators. Raw GGBFS samples and hardened pastes were characterized to provide rational explanations for the strengths and hydration products. The slag characteristics that influenced the best strength of raw GGBFS were identified. Although it is widely recognized that GGBFS alone generally shows little cementing capability when hydrated with water, the GGBFSs examined in this study demonstrated various strength developments and hydration behaviors; one of the GGBFS samples even produced a high strength comparable to that of alkali- or Ca(OH2-activated GGBFS. In particular, as the GGBFS exhibited a greater number of favorable slag characteristics for hydraulic reactivity, it produced more C-S-H and ettringite. The results demonstrated a reasonable potential for commercial GGBFS with calcium sulfates to function as an independent cementitious binder without activators.

  15. Effect of High-Temperature Curing Methods on the Compressive Strength Development of Concrete Containing High Volumes of Ground Granulated Blast-Furnace Slag

    Directory of Open Access Journals (Sweden)

    Wonsuk Jung

    2017-01-01

    Full Text Available This paper investigates the effect of the high-temperature curing methods on the compressive strength of concrete containing high volumes of ground granulated blast-furnace slag (GGBS. GGBS was used to replace Portland cement at a replacement ratio of 60% by binder mass. The high-temperature curing parameters used in this study were the delay period, temperature rise, peak temperature (PT, peak period, and temperature down. Test results demonstrate that the compressive strength of the samples with PTs of 65°C and 75°C was about 88% higher than that of the samples with a PT of 55°C after 1 day. According to this investigation, there might be optimum high-temperature curing conditions for preparing a concrete containing high volumes of GGBS, and incorporating GGBS into precast concrete mixes can be a very effective tool in increasing the applicability of this by-product.

  16. Electrical and electromagnetic investigations for HVDC ground electrode sites in India

    Science.gov (United States)

    Manglik, A.; Verma, S. K.; Muralidharan, D.; Sasmal, R. P.

    High Voltage Direct Current (HVDC) power transmission systems require setting up of specially designed ground electrodes at terminal ends of the transmission line to close the circuit with an earth return path. The design parameters of these electrodes need the information about the electrical conductivity structure within a radius and depth of several km of the site in order to ensure that the injected current penetrates deep enough into the earth. Further, detailed conductivity structure, up to 100-200 m depth, of the electrode site covering an area of less than a sq. km is also needed to ensure safe limits for the step and touch potential at the site. Electrical and electromagnetic methods are very useful tools for this purpose. However, artificial source variants such as deep direct current (DC) resistivity sounding pose logistic problems for target depths greater than a couple of kilometers and in inaccessible areas. We have employed magnetotelluric (MT) and electrical resistivity tomography (ERT) tools to investigate the detailed deep and shallow electrical conductivity structure, respectively, of several potential sites in India for a ±800 kV, 6000 MW HVDC multi-terminal system. Investigations of a site in Assam revealed the presence of highly resistive crustal rocks at the depth of about 1.3 km beneath a thick pile of conductive sediments, rendering the site unsuitable even though the shallow conductivity was favorable. At another site identified after analyzing available geological and geophysical data, we inferred the presence of conductive structure up to at least 4.0 km depth. ERT investigation at this site revealed a favorable conductive structure except for the presence of a 20-m-thick near-surface resistive layer. This information has been useful for the electrode design. We suggest that a strategy suitably combining MT and ERT is useful in the selection of ground electrode sites.

  17. Role of induced electrical polarization to identify soft ground/fractured rock conditions

    Science.gov (United States)

    Park, Jinho; Lee, Kang-Hyun; Seo, Hyungjoon; Ryu, Jinwoo; Lee, In-Mo

    2017-02-01

    This study attempted to evaluate the role and effectiveness of induced polarization (IP) along with electrical resistivity to identify soft ground/fractured rock. Theoretical studies as well as laboratory-scale experiments were conducted for this purpose. The theoretical study involved deriving the functional relationship between chargeability and influential variables. This was followed by performing a sensitivity analysis using the derived relationship to reveal that the size of narrow pores (r1) exerted the greatest influence on the chargeability followed by the salinity of the pore water (C0). In the laboratory test, a small-scale fractured rock zone was modeled using sandstone as a parent rock. The chargeability and resistivity were measured by changing the size of the joint aperture filled with tap water and/or sea water, the location of the fractured zone, and the thickness of the soil layer in a soil-rock multi-layered ground. The experimental study modeled the jointed zone between competent sandstone layers and indicated that the chargeability was mostly controlled by the size of the narrow pore (r1) of the surface sandstone and not by the porosity of the jointed zone. Hence, it was concluded that the chargeability did not significantly depend on the fractured characteristics of the jointed rock. It could be difficult to clearly distinguish as to whether the low resistivity value is caused by the sea water intrusion or by the increase in porosity of the fractured ground. However, the IP exploration can be effectively utilized to identify sea water intrusion since the chargeability decreased as the salinity of pore water increased. The experimental study on a soil-rock multi-layered ground indicated that the measured chargeability was controlled by the percentage of current flow that passed through the competent rock as well as by the narrow pore size of the rock itself. In conclusion, the ground condition could be easily identified by measuring the IP in

  18. Calculation of Electric Field at Ground Surface and ADSS Cable Prepared Hanging Point near EHV Power Transmission Tower

    Directory of Open Access Journals (Sweden)

    Xu Bao-Qing

    2016-01-01

    Full Text Available A simplified model of the 750kV tower is established by CDEGS software which is based on the Method Of Moment. The power frequency electric field distribution on the ground is achieved by software calculation and field-measuring. The validity of the calculation is proved when compare the calculation and experiment results. The model also can be used to calculate the electric field in prepared hanging points on the tower. Results show that the electric field distribution on the ground surface around the tower and prepared hanging points are meet the standard by calculation and experiment.

  19. Electrical and seismic mixing rules for detecting changes in ground ice content in permafrost studies

    Science.gov (United States)

    Hauck, Christian; Hilbich, Christin

    2017-04-01

    Geophysical methods are now widely used in permafrost research to detect and monitor frozen ground and potentially quantify the ground ice content in the soil. Hereby, often a combination of different methods is used to reduce the ambiguities inherent with the indirect nature of geophysical surveys. Geophysical mixing rules and petrophysical relationships originally developed by exploration industry may help to quantitatively relate geophysical variables such as the electrical resistivity or the seismic P-wave velocity to the physical properties of the subsurface. Two of these mixing rules were combined by Hauck et al. (2011) in a so-called 4-phase model to attempt to quantify the ground ice, air- and water content and their changes with time in permafrost environments (e.g. Pellet et al. 2016). However, these mixing rules are often either empirically derived (making use of a large number of borehole samples) or based on a simplified mixing model, i.e. an equal weighting of each phase component (ice, water, soil/rock, air) depending on the actual fractional content of each phase. There is thus no obvious 'best choice' model from the available geophysical approaches. Stimulated by recent theoretical work by Glover (2010), who analysed the relationships between the empirical and theory-derived mixing models, this contribution aims to analyse the applicability of various mixing models for electrical and seismic data sets in the context of detecting and monitoring permafrost degradation. Input data stem from various geophysical surveys around the world and ground truth data for validation is available from corresponding permafrost boreholes from the PERMOS and GTN-P data bases. Glover, P. W. (2010). A generalized Archie's law for n phases. Geophysics, 75(6), E247-E265. Hauck, C., Böttcher, M. and Maurer, H. (2011): A new model for estimating subsurface ice content based on combined electrical and seismic data sets. The Cryosphere, 5, 453-468. Pellet C., Hilbich C

  20. Simulative investigation on head injuries of electric self-balancing scooter riders subject to ground impact.

    Science.gov (United States)

    Xu, Jun; Shang, Shi; Qi, Hongsheng; Yu, Guizhen; Wang, Yunpeng; Chen, Peng

    2016-04-01

    The safety performance of an electric self-balancing scooter (ESS) has recently become a main concern in preventing its further wide application as a major candidate for green transportation. Scooter riders may suffer severe brain injuries in possible vehicle crash accidents not only from contact with a windshield or bonnet but also from secondary contact with the ground. In this paper, virtual vehicle-ESS crash scenarios combined with finite element (FE) car models and multi-body scooter/human models are set up. Post-impact kinematic gestures of scooter riders under various contact conditions, such as different vehicle impact speeds, ESS moving speeds, impact angles or positions, and different human sizes, are classified and analyzed. Furthermore, head-ground impact processes are reconstructed using validated FE head models, and important parameters of contusion and laceration (e.g., coup or contrecoup pressures and Von Mises stress and the maximum shear stress) are extracted and analyzed to assess the severity of regional contusion from head-ground contact. Results show that the brain injury risk increases with vehicle speeds and ESS moving speeds and may provide fundamental knowledge to popularize the use of a helmet and the vehicle-fitted safety systems, and lay a strong foundation for the reconstruction of ESS-involved accidents. There is scope to improve safety for the use of ESS in public roads according to the analysis and conclusions.

  1. 30 CFR 57.6312 - Secondary blasting.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Secondary blasting. 57.6312 Section 57.6312... Transportation-Surface and Underground § 57.6312 Secondary blasting. Secondary blasts fired at the same time in the same work area shall be initiated from one source. Electric Blasting—Surface and Underground...

  2. The Influence of Allocation on the Carbon Footprint of Electricity Production from Waste Gas, a Case Study for Blast Furnace Gas

    Directory of Open Access Journals (Sweden)

    Joeri Van Mierlo

    2013-03-01

    Full Text Available Producing electricity from waste gas is an after treatment for waste gas while recovering the energy content. This paper addresses the methodology to calculate the effect that waste gas energy recovery has on lowering the impact of climate change. Greenhouse gases are emitted while burning the waste gas. However, a thorough study should include the production of the feedstock as well as the production of the infrastructure. A framework is developed to calculate the environmental impact of electricity production from waste gas with a life cycle approach. The present paper has a twofold purpose: to assess the climate change impact of generating electricity with blast furnace gas (BFG as a waste gas from the steel industry; and to establish a sensitivity assessment of the environmental implications of different allocation rules.

  3. Mass and elemental distributions of atmospheric particles nearby blast furnace and electric arc furnace operated industrial areas in Australia.

    Science.gov (United States)

    Mohiuddin, Kazi; Strezov, Vladimir; Nelson, Peter F; Stelcer, Eduard; Evans, Tim

    2014-07-15

    The improved understanding of mass and elemental distributions of industrial air particles is important due to their heterogeneous atmospheric behaviour and impact on human health and the environment. In this study, particles of different size ranges were collected from three sites in Australia located in the vicinity of iron and steelmaking industries and one urban background site with very little industrial influence. In order to determine the importance of the type of industrial activity on the urban atmospheric quality, the industrial sites selected in this study were in the close proximity to two blast furnace operated and one electric arc furnace based steelmaking sites. The chemical compositions of the collected air particles were analysed using the proton induced X-ray emission (PIXE) technique. This study revealed significantly higher metal concentrations in the atmospheric particles collected in the industrial sites, comparing to the background urban site, demonstrating local influence of the industrial activities to the air quality. The modality types of the particles were found to be variable between the mass and elements, and among elements in the urban and industrial areas indicating that the elemental modal distribution is as important as particle mass for particle pollution modelling. The highest elemental number distribution at all studied sites occurred with particle size of 0.1 μm. Iron was found as the main dominant metal at the industrial atmosphere in each particle size range. The industrial Fe fraction in the submicron and ultrafine size particles was estimated at up to 95% which may be released from high temperature industrial activities with the iron and steelmaking industries being one of the major contributors. Hence, these industrial elemental loadings can highly influence the atmospheric pollution at local urban and regional levels and are required to consider in the atmospheric modelling settings.

  4. Electric Ground Support Equipment Advanced Battery Technology Demonstration Project at the Ontario Airport

    Energy Technology Data Exchange (ETDEWEB)

    Tyler Gray; Jeremy Diez; Jeffrey Wishart; James Francfort

    2013-07-01

    The intent of the electric Ground Support Equipment (eGSE) demonstration is to evaluate the day-to-day vehicle performance of electric baggage tractors using two advanced battery technologies to demonstrate possible replacements for the flooded lead-acid (FLA) batteries utilized throughout the industry. These advanced battery technologies have the potential to resolve barriers to the widespread adoption of eGSE deployment. Validation testing had not previously been performed within fleet operations to determine if the performance of current advanced batteries is sufficient to withstand the duty cycle of electric baggage tractors. This report summarizes the work performed and data accumulated during this demonstration in an effort to validate the capabilities of advanced battery technologies. This report summarizes the work performed and data accumulated during this demonstration in an effort to validate the capabilities of advanced battery technologies. The demonstration project also grew the relationship with Southwest Airlines (SWA), our demonstration partner at Ontario International Airport (ONT), located in Ontario, California. The results of this study have encouraged a proposal for a future demonstration project with SWA.

  5. TT系统接地和防电击简析%Analysis of TT System Grounding and Electric Shock Protection

    Institute of Scientific and Technical Information of China (English)

    王厚余

    2013-01-01

    阐述IEC 60364-4-41:2005《Low-voltage electrical installations-Part 4-41: Protection for safety-Protection against electric shock》标准规定TT系统内由同一保护电器所保护的所有电气设备必须采用共用接地防电击的原由,举例说明户外农电装置、施工场地、路灯等TT系统应用中的接地和防电击实施方案。着重叙述路灯TT系统共用接地并采用过电流防护电器兼防电击在我国的特殊现实意义。%To elaborate the reason why all electrical equipments protected by the same protective device must adopt common grounding to prevent electric shock as set up in Low-voltage Electrical Installations-Part 4-41:Protection for Safety-Protection against Electric Shock ( IEC 60364 - 4 - 41: 2005) , and to illustrate the implementation plan of grounding and electric shock prevention for outdoor rural power devices, construction sites and street lamps etc. with examples, in particular the special practical significance of TT system of street lamps with common grounding, adopting overcurrent protective devices to prevent against electric shock in China.

  6. Measuring the electrical properties of soil using a calibrated ground-coupled GPR system

    Science.gov (United States)

    Oden, C.P.; Olhoeft, G.R.; Wright, D.L.; Powers, M.H.

    2008-01-01

    Traditional methods for estimating vadose zone soil properties using ground penetrating radar (GPR) include measuring travel time, fitting diffraction hyperbolae, and other methods exploiting geometry. Additional processing techniques for estimating soil properties are possible with properly calibrated GPR systems. Such calibration using ground-coupled antennas must account for the effects of the shallow soil on the antenna's response, because changing soil properties result in a changing antenna response. A prototype GPR system using ground-coupled antennas was calibrated using laboratory measurements and numerical simulations of the GPR components. Two methods for estimating subsurface properties that utilize the calibrated response were developed. First, a new nonlinear inversion algorithm to estimate shallow soil properties under ground-coupled antennas was evaluated. Tests with synthetic data showed that the inversion algorithm is well behaved across the allowed range of soil properties. A preliminary field test gave encouraging results, with estimated soil property uncertainties (????) of ??1.9 and ??4.4 mS/m for the relative dielectric permittivity and the electrical conductivity, respectively. Next, a deconvolution method for estimating the properties of subsurface reflectors with known shapes (e.g., pipes or planar interfaces) was developed. This method uses scattering matrices to account for the response of subsurface reflectors. The deconvolution method was evaluated for use with noisy data using synthetic data. Results indicate that the deconvolution method requires reflected waves with a signal/noise ratio of about 10:1 or greater. When applied to field data with a signal/noise ratio of 2:1, the method was able to estimate the reflection coefficient and relative permittivity, but the large uncertainty in this estimate precluded inversion for conductivity. ?? Soil Science Society of America.

  7. Improvement of ground granulated blast furnace slag on stabilization/solidification of simulated mercury-doped wastes in chemically bonded phosphate ceramics.

    Science.gov (United States)

    Liu, Zhongzhe; Qian, Guangren; Zhou, Jizhi; Li, Chuanhua; Xu, Yunfeng; Qin, Zhe

    2008-08-30

    This paper investigated the effectiveness of (ground granulated blast furnace slag) GGBFS-added chemically bonded phosphate ceramic (CBPC) matrix on the stabilization/solidification (S/S) of mercury chloride and simulated mercury-bearing light bulbs (SMLB). The results showed that the maximal compressive strength was achieved when 15% and 10% ground GGBFS was added for HgCl(2)-doped and SMLB-doped CBPC matrices, respectively. The S/S performances of GGBFS-added matrices were significantly better than non-additive matrices. As pore size was reduced, the leaching concentration of Hg(2+) from GGBFS-added CBPC matrix could be reduced from 697 microg/L to about 3 microg/L when treating HgCl(2). Meanwhile, the main hydrating product of GGBFS-added matrices was still MgKPO(4).6H(2)O. The improvement of S/S effectiveness was mainly due to physical filling of fine GGBFS particles and microencapsulation of chemical cementing gel.

  8. REQUIREMENTS FOR DEVICES FOR VERTICAL ELECTRICAL SOUNDING OF SOIL AT DIAGNOSTICS OF GROUNDING DEVICES

    Directory of Open Access Journals (Sweden)

    S. S. Rudenko

    2016-11-01

    Full Text Available Purpose. Creation the scientific requirements for technical characteristics of equipment for vertical electrical sounding based on the electrophysical characteristics of the soil of energy objects with the different voltage classes. Methodology. In work used statistical methods for the analysis database of results the soil sounding and for receiving distribution of largest size of the grounding system. To determine the required range of measurement and permissible value of circuit resistance applied the mathematical description of the electromagnetic field to calculate the apparent resistivity of the soil and the Wenner method of calculating the resistance of a vertical electrode. Also, in work used elements of probability theory to creation the stochastic correlation between device parameters and characteristics object of the research. Results. In the paper found that in the most severe cases (when the depth of sounding is the three maximal diagonal of grounding at 99% energy objects in Ukraine the lower limit of resistance measurement for the respective classes of voltage must be no more than 1.3 milliohms to 35 kV, 0.6 mOhm to 110 kV, 0.5 milliohms to 150 kV, 0.1 mOhm for ≥ 220 kV. Also it proved that the measurement equipment for vertical electrical sounding when performing electromagnetic diagnostics of grounding system the power facilities Ukraine with 35-750 kV voltage class for all possible values of soil resistivity should be with limit of measurement from 0.1 mOhm to 7.2 kOhm and resistance measuring circuit to 66 kOhm. Originality.For the first time used a statistical approach to evaluate the optimal technical requirements for equipment the soils resistivity when performing diagnostics of grounding systems energy objects of Ukraine. The results obtained in this work, establish the probabilistic dependence of the technical characteristics of measuring equipment from the actual depth of sounding in Wenners configuration (the distance

  9. Modelling the Influence of Ground Surface Relief on Electric Sounding Curves Using the Integral Equations Method

    Directory of Open Access Journals (Sweden)

    Balgaisha Mukanova

    2017-01-01

    Full Text Available The problem of electrical sounding of a medium with ground surface relief is modelled using the integral equations method. This numerical method is based on the triangulation of the computational domain, which is adapted to the shape of the relief and the measuring line. The numerical algorithm is tested by comparing the results with the known solution for horizontally layered media with two layers. Calculations are also performed to verify the fulfilment of the “reciprocity principle” for the 4-electrode installations in our numerical model. Simulations are then performed for a two-layered medium with a surface relief. The quantitative influences of the relief, the resistivity ratios of the contacting media, and the depth of the second layer on the apparent resistivity curves are established.

  10. Atmospheric electric discharges and grounding systems; Descargas atmosfericas y sistemas de conexion a tierra

    Energy Technology Data Exchange (ETDEWEB)

    Rivas, Elena [ed.] [Instituto de Investigaciones Electricas, Temixco, Morelos (Mexico)

    1999-07-01

    In this article the work made by the Institute of Investigaciones Electricas (IIE), in the area of atmospheric electric discharges and grounding connections at Comision Federal de Electricidad (CFE) is presented. The work consisted of the revision of the procedures for the design of transmission lines and substations of CFE from which high indexes of interruptions are reported, from this, a program was defined that allowed to improve the existing designs in CFE. [Spanish] En este articulo se presenta el trabajo realizado por el Instituto de Investigaciones Electricas (IIE), en el area de descargas atmosfericas y conexiones a tierra en Comision Federal de Electricidad (CFE). El trabajo consistio en la revision de los procedimientos de diseno de las areas de transmision y subestaciones de la CFE para los que se reportan altos indices de salidas, a partir de esto se definio un programa que permitio mejorar los disenos existentes en la CFE.

  11. Rock mass response to strong ground motion generated by mining induced seismic events and blasting observed at the surface of the excavations in deep level gold mines in South Africa

    Science.gov (United States)

    Milev, Alexander; Durrheim, Ray; Ogasawara, Hiroshi

    2014-05-01

    The strong ground motion generated by mining induced seismic events was studied to characterize the rock mass response and to estimate the site effect on the surface of the underground excavations. A stand-alone instruments, especially designed for recording strong ground motions, were installed underground at a number of deep level gold mines in South Africa. The instruments were recording data at the surface of the stope hangingwalls. A maximum value of 3 m/s was measured. Therefore data were compared to the data recorded in the solid rock by the mine seismic networks to determine the site response. The site response was defined as the ratio of the peak ground velocity measured at the surface of the excavations to the peak ground velocity inferred from the mine seismic data measured in the solid rocks. The site response measured at all mines studied was found to be 9 ± 3 times larger on average. A number of simulated rockbursts were conducted underground in order to estimate the rock mass response when subjected to extreme ground motion and derive the attenuation factors in near field. The rockbursts were simulated by means of large blasts detonated in solid rock close to the sidewall of a tunnel. The numerical models used in the design of the simulated rockbursts were calibrated by small blasts taking place at each experimental site. A dense array of shock type accelerometers was installed along the blasting wall to monitor the attenuation of the strong ground motion as a function of the distance from the source. The attenuation of the ground motion was found to be proportional to the distance from the source following R^-1.1 & R^-1.7 for compact rock and R^-3.1 & R^-3.4 for more fractured rock close to the surface of the tunnel. In addition the ground motion was compared to the quasi-static deformations taking place around the underground excavations. The quasi-static deformations were measured by means of strain, tilt and closure. A good correspondence

  12. The variation of the ground electric field associated with the Mei-Nung earthquake on Feb. 6, 2016

    Science.gov (United States)

    Bing-Chih Chen, Alfred; Yeh, Er-Chun; Chuang, Chia-Wen

    2017-04-01

    Recent studies show that a strong coupling exists between lithosphere, atmosphere and extending up to the ionosphere. Natural phenomena on the ground surface such as oceans variation, volcanic and seismic activities such as earthquakes, and lightning possibly generate significant impacts at ionosphere immediately by electrodynamic processes. The electric field near the ground is one of the potential quantities to explore this coupling process, especially caused by earthquake. Unfortunately, thunderstorm, dust storm or human activities also affect the measured electric field at ground. To investigate the feasibility of a network to monitor the variation of the ground electric field driven by the lightning and earthquake, a filed mill has been deployed in the NCKU campus since Dec. 2015, and luckily experienced the earthquake with a moment magnitude of 6.4 struck 28 km on 6 Feb. 2016. The recorded ground electric field deceased steadily since 1.5 days before the earthquake, and returned to normal level gradually. Moreover, this special feature can not be identified in the other period of the field test. The detail analysis is reported in this presentation.

  13. Effect of near-earth thunderstorms electric field on the intensity of ground cosmic ray positrons/electrons in Tibet

    Science.gov (United States)

    Zhou, X. X.; Wang, X. J.; Huang, D. H.; Jia, H. Y.

    2016-11-01

    Monte Carlo simulations are performed to study the correlation between the ground cosmic ray intensity and near-earth thunderstorms electric field at YBJ (located at YangBaJing, Tibet, China, 4300 m a. s. l.). The variations of the secondary cosmic ray intensity are found to be highly dependent on the strength and polarity of the electric field. In negative fields and in positive fields greater than 600 V/cm, the total number of ground comic ray positrons and electrons increases with increasing electric field strength. And these values increase more obviously when involving a shower with lower primary energy or a higher zenith angle. While in positive fields ranging from 0 to 600 V/cm, the total number of ground comic ray positrons and electrons declines and the amplitude is up to 3.1% for vertical showers. A decrease of intensity occurs in inclined showers within the range of 0-500 V/cm, which is accompanied by smaller amplitudes. In this paper, the intensity changes are analyzed, especially concerning those decreasing phenomena in positive electric fields. Our simulation results could be helpful in understanding the decreases observed in some ground-based experiments (such as the Carpet air shower array and ARGO-YBJ), and also be useful in understanding the acceleration mechanisms of secondary charged particles caused by an atmospheric electric field.

  14. The use of blast furnace slag

    Directory of Open Access Journals (Sweden)

    V. Václavík

    2012-10-01

    Full Text Available The paper presents the results of experimental research that dealt with the substitution of finely ground blast furnace slag for Portland cement in the course of simple concrete manufacturing. Physical and mechanical properties of experimental concrete mixtures based on finely ground blast furnace slag were observed.

  15. The use of blast furnace slag

    OpenAIRE

    V. Václavík; V. Dirner; T. Dvorský; J. Daxner

    2012-01-01

    The paper presents the results of experimental research that dealt with the substitution of finely ground blast furnace slag for Portland cement in the course of simple concrete manufacturing. Physical and mechanical properties of experimental concrete mixtures based on finely ground blast furnace slag were observed.

  16. Mass and elemental distributions of atmospheric particles nearby blast furnace and electric arc furnace operated industrial areas in Australia

    Energy Technology Data Exchange (ETDEWEB)

    Mohiuddin, Kazi, E-mail: kazi.mohiuddin@students.mq.edu.au [Graduate School of the Environment, Department of Environment and Geography, Faculty of Science, Macquarie University, NSW (Australia); Strezov, Vladimir; Nelson, Peter F. [Graduate School of the Environment, Department of Environment and Geography, Faculty of Science, Macquarie University, NSW (Australia); Stelcer, Eduard [Australian Nuclear Science and Technology Organisation, Lucas Heights, NSW (Australia); Evans, Tim [Graduate School of the Environment, Department of Environment and Geography, Faculty of Science, Macquarie University, NSW (Australia)

    2014-07-01

    The improved understanding of mass and elemental distributions of industrial air particles is important due to their heterogeneous atmospheric behaviour and impact on human health and the environment. In this study, particles of different size ranges were collected from three sites in Australia located in the vicinity of iron and steelmaking industries and one urban background site with very little industrial influence. In order to determine the importance of the type of industrial activity on the urban atmospheric quality, the industrial sites selected in this study were in the close proximity to two blast furnace operated and one electric arc furnace based steelmaking sites. The chemical compositions of the collected air particles were analysed using the proton induced X-ray emission (PIXE) technique. This study revealed significantly higher metal concentrations in the atmospheric particles collected in the industrial sites, comparing to the background urban site, demonstrating local influence of the industrial activities to the air quality. The modality types of the particles were found to be variable between the mass and elements, and among elements in the urban and industrial areas indicating that the elemental modal distribution is as important as particle mass for particle pollution modelling. The highest elemental number distribution at all studied sites occurred with particle size of 0.1 μm. Iron was found as the main dominant metal at the industrial atmosphere in each particle size range. The industrial Fe fraction in the submicron and ultrafine size particles was estimated at up to 95% which may be released from high temperature industrial activities with the iron and steelmaking industries being one of the major contributors. Hence, these industrial elemental loadings can highly influence the atmospheric pollution at local urban and regional levels and are required to consider in the atmospheric modelling settings. - Highlights: • Urban and

  17. [Solidification/Stabilization of Chromite Ore Processing Residue (COPR) Using Zero-Valent Iron and Lime-Activated Ground Granulated Blast Furnace Slag].

    Science.gov (United States)

    Chen, Zhong-lin; Li, Jin-chunzi; Wang, Bin-yuan; Fan, Lei-tao; Shen, Ji-min

    2015-08-01

    The solidification/stabilization (S/S) of chromite ore processing residue (COPR) was performed using zero-valent iron (ZVI) and lime-activated ground granulated blast furnace slag (GGBFS). The degree of Cr immobilization was evaluated using the leaching procedure, mineral composition analysis and morphology analysis. Semi-dynamic leaching tests were implemented to investigate the potential for reusing the final treatment product as a readily available construction material. The results showed that after reduction, all of the S/S treated COPR samples met the pollution control limit of bricks and building block products (Chinese standard HJ/T 301-2007) produced with COPR for total Cr (0.3 mg x L(-1)), the compressive strength of all the S/S samples could meet the compressive strength standard (15 MPa) for producing clay bricks, and Cr existed as the specie that bound to Fe/Mn oxides in the S/S samples. At the same time, all of the S/S treated specimens tested were suitable for utilization at certain levels.

  18. A forward model for ground penetrating radar imaging of buried perfect electric conductors within the physical optics approximation

    DEFF Research Database (Denmark)

    Polat, Burak; Meincke, Peter

    2004-01-01

    A forward model for ground penetrating radar imaging of buried 3-D perfect electric conductors is addressed within the framework of diffraction tomography. The similarity of the present forward model derived within the physical optics approximation with that derived within the first Born...

  19. Reduced Order Modeling for Rapid Simulations of Blast and Rollover Events of a Ground Vehicle and its Occupants Using Rigid Body Dynamic Models

    Science.gov (United States)

    2013-03-11

    IED, SimBRS, PSM , blastoff, slamdown, UBM, facet, pressure, ROM, injury, lsDYNA 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18...Prescribed accelerative vertical motion / PSM ....................................................................................... 25 Blast pressure...33 Figure 5.4 Kinematics at 50 msec for LS-Dyna output with ConWep blast force, and MADYMO output with PSM for all nodes

  20. Detectability of underground electrical cables junction with a ground penetrating radar: electromagnetic simulation and experimental measurements

    Science.gov (United States)

    Liu, Xiang; serhir, mohammed; kameni, abelin; lambert, marc; pichon, lionel

    2016-04-01

    For a company like Electricity De France (EDF), being able to detect accurately using non-destructive methods the position of the buried junction between two underground cables is a crucial issue. The junction is the linking part where most maintenance operations are carried out. The challenge of this work is to conduct a feasibility study to confirm or deny the relevance of Ground Penetrating Radar (GPR) to detect these buried junctions in their actual environment against clutter. Indeed, the cables are buried in inhomogeneous medium at around 80cm deep. To do this, the study is conducted in a numerical environment. We use the 3D simulation software CST MWS to model a GPR scenario. In this simulation, we place the already optimized bowtie antennas operating in the frequency band [0.5 GHz - 3 GHz] in front of wet soil (dispersive) and dry soil where the underground cable is placed at 80cm deep. We collect the amplitude and phase of the reflected waves in order to detect the contrast provoked by the geometric dimensions variation of the cable [1] (diameter of the cable is 48mm and the diameter of the junction 74mm). The use of an ultra-wideband antenna is necessary to reconcile resolution and penetration of electromagnetic waves in the medium to be characterized. We focus on the performance of the GPR method according to the characteristics of the surrounding medium in which the electric cables are buried, the polarization of the Tx and Rx antennas. The experimental measurement collected in the EDF site will be presented. The measured data are processed using the clutter reduction method based on digital filtering [2]. We aim at showing that using the developed bowtie antennas that the GPR technique is well adapted for the cable junction localization even in cluttered environment. References [1] D. J. Daniels, "Surface-Penetrating Radar", London, IEE 1996. [2] Potin, D.; Duflos, E.; Vanheeghe, P., "Landmines Ground-Penetrating Radar Signal Enhancement by Digital

  1. Vertical drainage capacity of new electrical drainage board on improvement of super soft clayey ground

    Institute of Scientific and Technical Information of China (English)

    沈扬; 励彦德; 黄文君; 徐海东; 胡品飞

    2015-01-01

    As an advanced polymer composites electro-kinetic geosynthetics, the electro-osmotic vertical drainage (EVD) board could drain water quickly and accelerate consolidation process. However, the drainage rate was mainly impacted by the vertical drainage capability. Therefore, vertical drainage capability at the top of EVD board was theoretically analyzed. Basic requirements for drainage at the top of the board were summed up, as well as the formula of anode pore pressure when losing the vertical drainage capability. Meanwhile, a contrast test on the top and bottom drainage capacities was conducted. In use of the advanced EVD board, the voltage potential and pore pressure of anode were measured. Moreover, the derived formulas were verified. The result shows that the decrease of electric force gradient had an observable impact on the drainage capability. There was nearly no difference between the energy consumption for the two drainage methods. Although a little less water was discharged, the top drainage method had more advantages, such as high initial drainage velocity, few soil cracks, low anode water content and high soil strength. All of these show that the super soft soil ground could be consolidated quickly in use of the advanced EVD board through the top drainage. The top drainage method could efficiently improve the drainage effect, decrease the energy consumption and speed up the project proceeding.

  2. Urban archaeological investigations using surface 3D Ground Penetrating Radar and Electrical Resistivity Tomography methods

    Science.gov (United States)

    Papadopoulos, Nikos; Sarris, Apostolos; Yi, Myeong-Jong; Kim, Jung-Ho

    2009-02-01

    Ongoing and extensive urbanisation, which is frequently accompanied with careless construction works, may threaten important archaeological structures that are still buried in the urban areas. Ground Penetrating Radar (GPR) and Electrical Resistivity Tomography (ERT) methods are most promising alternatives for resolving buried archaeological structures in urban territories. In this work, three case studies are presented, each of which involves an integrated geophysical survey employing the surface three-dimensional (3D) ERT and GPR techniques, in order to archaeologically characterise the investigated areas. The test field sites are located at the historical centres of two of the most populated cities of the island of Crete, in Greece. The ERT and GPR data were collected along a dense network of parallel profiles. The subsurface resistivity structure was reconstructed by processing the apparent resistivity data with a 3D inversion algorithm. The GPR sections were processed with a systematic way, applying specific filters to the data in order to enhance their information content. Finally, horizontal depth slices representing the 3D variation of the physical properties were created. The GPR and ERT images significantly contributed in reconstructing the complex subsurface properties in these urban areas. Strong GPR reflections and high-resistivity anomalies were correlated with possible archaeological structures. Subsequent excavations in specific places at both sites verified the geophysical results. The specific case studies demonstrated the applicability of ERT and GPR techniques during the design and construction stages of urban infrastructure works, indicating areas of archaeological significance and guiding archaeological excavations before construction work.

  3. Improving Indonesian peatland C stock estimates using ground penetrating radar (GPR) and electrical resistivity imaging (ERI)

    Science.gov (United States)

    Terry, N.; Comas, X.; Slater, L. D.; Warren, M.; Kolka, R. K.; Kristijono, A.; Sudiana, N.; Nurjaman, D.; Darusman, T.

    2014-12-01

    Tropical peatlands sequester an estimated 15% of the carbon pool from peatlands worldwide. Indonesian peatlands account for approximately 65% of all tropical peat, and are believed to be the largest global source of carbon dioxide emissions to the atmosphere from degrading peat. However, there is great uncertainty in these estimates due to insufficient data regarding the thickness of organic peat soils and their carbon content. Meanwhile, Indonesian peatlands are threatened by heightening pressure to drain and develop. Indirect geophysical methods have garnered interest for their potential to non-invasively estimate peat depth and gas content in boreal peatlands. Drawing from these techniques, we employed ground penetrating radar (GPR) and electrical resistivity imaging (ERI) in tandem with direct methods (core sampling) to evaluate the potential of these methods for tropical peatland mapping at 2 distinct study sites on West Kalimantan (Indonesia). We find that: [1] West Kalimantan peatland thicknesses estimated from GPR and ERI in intermediate/shallow peat can vary substantially over short distances (for example, > 2% over less than 0.02° surface topography gradient), [2] despite having less vertical resolution, ERI is able to better resolve peatland thickness in deep peat, and [3] GPR provides useful data regarding peat matrix attributes (such as the presence of wood layers). These results indicate GPR and ERI could help reduce uncertainty in carbon stocks and aid in responsible land management decisions in Indonesia.

  4. Blast Technologies

    Science.gov (United States)

    2011-06-27

    Team Leader Risa Scherer Blast Mitigation Interior and Laboratory Team Leader Blast Technologies POC’s Government Point Of Contacts (POCs): To...to yield injury assessments at higher fidelities and with higher confidence UNCLASSIFIED UNCLASSIFIED Risa Scherer Blast Mitigation Interior and

  5. Use of CaO as an activator for producing a price-competitive non-cement structural binder using ground granulated blast furnace slag

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Min Sik; Jun, Yubin; Lee, Changha, E-mail: clee@unist.ac.kr; Oh, Jae Eun, E-mail: ohjaeeun@unist.ac.kr

    2013-12-15

    The use of calcium oxide (CaO) demonstrates a superior potential for the activation of ground granulated blast furnace slag (GGBFS), and it produces a higher mechanical strength than calcium hydroxide [Ca(OH){sub 2}]. The mechanical strength differences between CaO- and Ca(OH){sub 2}-activated GGBFS binders are explored using isothermal calorimetry, powder X-ray diffraction, thermogravimetric and differential thermal analysis (TGA and DTA) as well as compressive strength testing. Calcium silicate hydrate (C–S–H), Ca(OH){sub 2} and a hydrotalcite-like phase are found as reaction products in all samples. The TGA and DTA results indicate that the use of CaO produces more C–S–H, although this is not likely to be the primary cause of higher strength development in the CaO-activated GGBFS. Rather, other factors such as porosity may govern the strength at a higher order of magnitude. Significant reduction of Ca(OH){sub 2} occurs only with the use of Ca(OH){sub 2}, followed by the formation of carbonate (CaCO{sub 3}), indicating carbonation. -- Highlights: •CaO showed a better potential for the activation of GGBFS than Ca(OH){sub 2}. •Strength test, XRD, TGA/DTA and isothermal calorimetry are used. •C-S-H, Ca(OH){sub 2}, and a hydrotalcite-like phase are found in all samples. •The use of Ca(OH){sub 2} causes some degree of carbonation.

  6. Testing of ground fault relay response during the energisation of megawatt range electric boilers in thermal power plants

    DEFF Research Database (Denmark)

    Silva, Filipe Miguel Faria da; Bak, Claus Leth; Davidsen, Troels

    2015-01-01

    , during the energisation of a boiler. A special case for concern was the presence of an electric arc between the electrodes of the boiler and the water in the boiler during approximately 2s at the energisation, which can in theory be seen as a ground fault by the relay. The voltage and current transient......Large controllable loads may support power systems with an increased penetration of fluctuating renewable energy, by providing a rapid response to a change in the power production. Megawatt range electric boilers are an example of such controllable loads, capable of change rapidly...

  7. Cost Benefit Analysis Modeling Tool for Electric vs. ICE Airport Ground Support Equipment – Development and Results

    Energy Technology Data Exchange (ETDEWEB)

    James Francfort; Kevin Morrow; Dimitri Hochard

    2007-02-01

    This report documents efforts to develop a computer tool for modeling the economic payback for comparative airport ground support equipment (GSE) that are propelled by either electric motors or gasoline and diesel engines. The types of GSE modeled are pushback tractors, baggage tractors, and belt loaders. The GSE modeling tool includes an emissions module that estimates the amount of tailpipe emissions saved by replacing internal combustion engine GSE with electric GSE. This report contains modeling assumptions, methodology, a user’s manual, and modeling results. The model was developed based on the operations of two airlines at four United States airports.

  8. Effect of near-earth thunderstorms electric field on the intensity of ground cosmic ray positrons/electrons in Tibet

    CERN Document Server

    Zhou, X X; Huang, D H; Jia, H Y

    2016-01-01

    Monte Carlo simulations are performed to study the correlation between the ground cosmic ray intensity and near-earth thunderstorms electric field at YBJ (4300 m a.s.l., Tibet, China). The variations of the secondary cosmic ray intensity are found to be highly dependent on the strength and polarity of the electric field. In negative fields and in positive fields greater than 600 V/cm, the total number of ground comic ray positrons and electrons increases with increasing electric field strength. And these values increase more obviously when involving a shower with lower primary energy or a higher zenith angle. While in positive fields ranging from 0 to 600 V/cm, the total number of ground comic ray positrons and electrons declines and the amplitude is up to 3.1% for vertical showers. A decrease of intensity occurs for inclined showers in positive fields less than 500 V/cm, which is accompanied by smaller amplitudes. In this paper, the intensity changes are discussed, especially concerning the decreases in posi...

  9. 30 CFR 57.6404 - Separation of blasting circuits from power source.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Separation of blasting circuits from power... NONMETAL MINES Explosives Electric Blasting-Surface and Underground § 57.6404 Separation of blasting circuits from power source. (a) Switches used to connect the power source to a blasting circuit shall...

  10. 22 CFR 121.11 - Military demolition blocks and blasting caps.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 1 2010-04-01 2010-04-01 false Military demolition blocks and blasting caps... blasting caps. Military demolition blocks and blasting caps referred to in Category IV(a) do not include the following articles: (a) Electric squibs. (b) No. 6 and No. 8 blasting caps, including...

  11. 30 CFR 56.6404 - Separation of blasting circuits from power source.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Separation of blasting circuits from power... MINES Explosives Electric Blasting § 56.6404 Separation of blasting circuits from power source. (a) Switches used to connect the power source to a blasting circuit shall be locked in the open position...

  12. 电雷管脚线成型工艺设备现状与发展趋势%Present Situation and Trends of Process and Equipment of Winding Electric Detonator Lighting Blasting Cap Wire

    Institute of Scientific and Technical Information of China (English)

    杨民刚; 夏光; 杨宗玲

    2014-01-01

    Basing on the production process of winding electric detonator lighting blasting cap wire, the present situation of process and equipment were discussed. With the guidance on the progress of civilian explosives materials technology, the development direction and technical ideas of process technology and equipment for winding electric detonator lighting blasting cap wire were put forward.%在简述电雷管脚线打把生产工艺的基础上,对工艺技术与设备现状进行了分析评述,结合民用爆炸物品技术进步指导意见,提出了工业电雷管脚线制作的工艺技术与设备发展方向和技术思路。

  13. BEHAVIOUR OF BACKFILL MATERIALS FOR ELECTRICAL GROUNDING SYSTEMS UNDER HIGH VOLTAGE CONDITIONS

    Directory of Open Access Journals (Sweden)

    S. C. LIM

    2015-06-01

    Full Text Available Backfill materials like Bentonite and cement are effective in lowering grounding resistance of electrodes for a considerable period. During lightning, switching impulses and earth fault occurrences in medium and high voltage networks, the grounding system needs to handle extremely high currents either for a short duration or prolonged period respectively. This paper investigates the behaviour of bentonite, cement and sand under impulse and alternating high voltage (50Hz conditions. Fulguritic-formation was observed in all materials under alternating high voltage. The findings reveal that performance of grounding systems under high voltage conditions may significantly change from the outcomes anticipated at design stage.

  14. Induced caving by blasting: innovative experiments in blasting gallery panels of underground coal mines of India

    Energy Technology Data Exchange (ETDEWEB)

    Roy, P.P.; Sawmliana, C.; Bhagat, N.K.; Madhu, M. [CMRI, Dhanbad (India). Blasting Dept.

    2003-04-01

    Induced caving by blasting during depillaring of panels in underground coal mines has received limited attention. This technique has become an integral part of a mining operation known as the blasting gallery (BG) method in India. Systematical deep hole (16-30 m) blasting has been successfully carried out from underground split galleries in BG panels. A study of drilling and blasting parameters, gas hazards, strata behaviour and ground vibration was undertaken as part of a research project for the Indian Ministry of Coal and Mines. Strata behaviour during blasting and ground movements were critically investigated. All experiments were conducted using newly developed explosive and detonating cord systems. A new blast damage index is proposed for damage assessment of the underground roof and pillars of BG panels. Useful mathematical formulas are described as an aid to future design.

  15. International Aerospace and Ground Conference on Lightning and Static Electricity. 1984 technical papers. Supplement

    Science.gov (United States)

    1984-01-01

    The indirect effects of lightning on digital systems, ground system protection, and the corrosion properties of conductive materials are addressed. The responses of a UH-60A helicopter and tactical shelters to lightning and nuclear electromagnetic pulses are discussed.

  16. High-resolution electrical resistivity tomography applied to patterned ground, Wedel Jarlsberg Land, south-west Spitsbergen

    Directory of Open Access Journals (Sweden)

    Marek Kasprzak

    2015-06-01

    Full Text Available This article presents results of two-dimensional electrical resistivity tomography (ERT applied to three types of patterned ground in Wedel-Jarlsberg Land (Svalbard, carried out in late July 2012. The structures investigated include sorted circles, non-sorted polygons and a net with sorted coarser material. ERT was used to recognize the internal ground structure, the shape of permafrost table below the active layer and the geometric relationships between permafrost, ground layering and surface patterns. Results of inversion modelling indicate that the permafrost table occurs at a depth of 0.5–1 m in a mountain valley and 1–2.5 m on raised marine terraces. The permafrost table was nearly planar beneath non-sorted deposits and wavy beneath sorted materials. The mutual relationships between the permafrost table and the shape of a stone circle are different from those typically presented in literature. Ground structure beneath the net with sorted coarser materials is complex as implied in convective models. In non-sorted polygons, the imaging failed to reveal vertical structures between them.

  17. Permanent Electron Electric Dipole Moment Search in the X^3Δ_1 Ground State of Tungsten Carbide Molecules

    Science.gov (United States)

    Lee, Jeongwon; Chen, Jinhai; Leanhardt, Aaron

    2011-06-01

    We are developing an experiment to search for the permanent electric dipole moment (EDM) of the electron using the valence electrons in the X^3Δ_1 ground state of Tungsten Carbide (WC) molecules. Currently, we are detecting the molecules by Laser Induced Fluorescence spectroscopy at ˜75cm downstream of a pulsed ablation beam source. We have a detection rate of ˜10 182W12C molecules/second in X^3Δ_1, v"=0, J"=1 state with geometric detection efficiency of 0.004. A continuous WC molecular beam is under development. Additionally, preliminary measurements of the 183W12C hyperfine structure will be presented.

  18. Static electric and magnetic multipole susceptibilities for Dirac one-electron atoms in the ground state

    Science.gov (United States)

    Szmytkowski, Radosław; Łukasik, Grzegorz

    2016-09-01

    We present tabulated data for several families of static electric and magnetic multipole susceptibilities for hydrogenic atoms with nuclear charge numbers from the range 1 ⩽ Z ⩽ 137. Atomic nuclei are assumed to be point-like and spinless. The susceptibilities considered include the multipole electric polarizabilities α E L → E L and magnetizabilities (magnetic susceptibilities) χ M L → M L with 1 ⩽ L ⩽ 4 (i.e., the dipole, quadrupole, octupole and hexadecapole ones), the electric-to-magnetic cross-susceptibilities α E L → M(L - 1) with 2 ⩽ L ⩽ 5 and α E L → M(L + 1) with 1 ⩽ L ⩽ 4, the magnetic-to-electric cross-susceptibilities χ M L → E(L - 1) with 2 ⩽ L ⩽ 5 and χ M L → E(L + 1) with 1 ⩽ L ⩽ 4 (it holds that χ M L → E(L ∓ 1) =α E(L ∓ 1) → M L), and the electric-to-toroidal-magnetic cross-susceptibilities α E L → T L with 1 ⩽ L ⩽ 4. Numerical values are computed from general exact analytical formulas, derived by us elsewhere within the framework of the Dirac relativistic quantum mechanics, and involving generalized hypergeometric functions 3F2 of the unit argument.

  19. Correlation between the spectral features and electric field changes of multiple return strokes in negative cloud-to-ground lightning

    Science.gov (United States)

    Wang, Xuejuan; Yuan, Ping; Cen, Jianyong; Liu, Guorong

    2017-05-01

    Using high time-resolved spectra and simultaneous records of the electric field change of three negative cloud-to-ground (CG) lightning flashes with multiple return strokes, the correlations between the total intensity of ionic lines in the spectra and the corresponding amplitude of the initial electric field change, as well as between the total intensity of the spectra and the channel apparent diameter, have been analyzed. The analysis shows the following: (1) The amplitude of the initial electric field change is roughly proportional to the total intensity of ionic lines. (2) The total intensity of the spectra shows a significant linear correlation with the apparent diameter of the channel. (3) The total intensity of ionic lines for 17 analyzed return strokes decreases with increasing height along the channel, which is consistent with the current variation along the channel in the modified transmission line model; the Master, Uman, Lin, and Standler model; and the Diendorfer-Uman model. Meanwhile, the total intensity of ionic lines for other two analyzed return strokes along the channel without attenuation, this is consistent with the current variation along the channel in the Bruce-Golde model, the transmission line model, and the Traveling Current Source model.

  20. Investigating fluvial features with electrical resistivity imaging and ground-penetrating radar: The Guadalquivir River terrace (Jaen, Southern Spain)

    Science.gov (United States)

    Rey, J.; Martínez, J.; Hidalgo, M. C.

    2013-09-01

    A geophysical survey has been conducted on the lowest terrace levels and the present day floodplain of the current course of the Guadalquivir River, passing through the province of Jaen (Spain), using two techniques: electrical resistivity imaging (ERI) and ground-penetrating radar (GPR). Three areas have been selected. In one of these sectors (Los Barrios) there is an old quarry where there are excellent outcrops that allow for the calibration of the survey techniques. Facies associations on these outcrops are typical of meandering rivers with sequences of channel fills, lateral accretion of point-bars and floodplain facies. The usefulness of the two methods is analysed and compared as a support for stratigraphic and sedimentological studies. The geometry and lithofacies of subsurface deposits were characterised using ERI and compared with field observations. A total of 5 electrical resistivity imaging profiles were obtained. The changes in electric resistivity highlight granulometric differences in terrace sediments. This technique can thus be used to identify the morphology of these bodies, the lithofacies (silt, sand or gravel) and buried channel pattern. In addition, 16 GPR profiles using 100 and 250 MHz antennas were acquired, indicating terrace morphology and the filling of the sedimentary bodies in a more detailed manner than in ERI. The study thus allows for inferring the existence of channel migration, the lateral accretion of point bars and the presence of vertical accretion deposits attributable to the floodplains.

  1. Permafrost Changes along the Alaska Highway Corridor, Southern Yukon, from Ground Temperature Measurements and DC Electrical Resistivity Tomography

    Science.gov (United States)

    Duguay, M. A.; Lewkowicz, A. G.; Smith, S.

    2011-12-01

    A natural gas pipeline running across permafrost terrain from Prudhoe Bay, Alaska, through Canada to US markets was first proposed more than 30 years ago. In the intervening period, mean annual air temperatures in the region have risen by 0.5-1.0°C and it is probable that the ground has also warmed. Renewed interest in the pipeline has meant that information on permafrost and geotechnical conditions within the Alaska Highway Corridor of the southern Yukon must be updated for engineering design and the assessment of environmental impacts. To accomplish this goal, results from 1977-1981 drilling and ground temperature monitoring programs within the proposed pipeline corridor were used in combination with air photo analysis to select sites potentially sensitive to climate change. The sites are distributed across the extensive and sporadic discontinuous permafrost zones over a distance of 475 km between Beaver Creek and Whitehorse. To date, 11 targeted boreholes with permafrost have been found and cased to permit renewed ground temperature monitoring. By the end of summer 2011, it is expected that another 7 will have been instrumented. Measurable temperature increases relative to the 1970s are expected, except where values were previously just below 0°C. In the latter case, if the sites are still in permafrost, latent heat effects may have substantially moderated the temperature increase. Electrical resistivity tomography surveys are also being conducted to characterize the local permafrost distribution and geotechnical conditions. These 2D resistivity profiles will be used with the ground temperatures to examine current conditions and response to climate change and vegetation disturbance.

  2. Reducing Drill and Blast Cost through Blast Optimisation – A Case ...

    African Journals Online (AJOL)

    Michael O. Mensah

    2015-12-02

    Dec 2, 2015 ... for each active pit, for ore and waste zones, were assessed with the Kuz-Ram fragmentation model. ... fragmentation and wall control are technical areas that have well ..... of ground vibration, air blast or air overpressures,.

  3. Mapping refuse profile in Singapore old dumping ground through electrical resistivity, S-wave velocity and geotechnical monitoring.

    Science.gov (United States)

    Yin, Ke; Tong, Huan Huan; Noh, Omar; Wang, Jing-Yuan; Giannis, Apostolos

    2015-03-01

    The purpose of this study was to track the refuse profile in Lorong Halus Dumping Ground, the largest landfill in Singapore, by electrical resistivity and surface wave velocity after 25 years of closure. Data were analyzed using an orthogonal set of plots by spreading 24 lines in two perpendicular geophone-orientation directions. Both geophysical techniques determined that refuse boundary depth was 13 ± 2 m. The refuse boundary revealed a certain degree of variance, mainly ascribed to the different principle of measurements, as well as the high heterogeneity of the subsurface. Discrepancy was higher in spots with greater heterogeneity. 3D analysis was further conducted detecting refuse pockets, leachate mounding and gas channels. Geotechnical monitoring (borehole) confirmed geophysical outcomes tracing different layers such as soil capping, decomposed refuse materials and inorganic wastes. Combining the geophysical methods with borehole monitoring, a comprehensive layout of the dumping site was presented showing the hot spots of interests.

  4. Estimation of submarine groundwater discharge from bulk ground electrical conductivity measurements

    Science.gov (United States)

    Stieglitz, Thomas; Rapaglia, John; Bokuniewicz, Henry

    2008-08-01

    The utility of bulk ground conductivity (BGC) measurements in the estimation of submarine groundwater discharge (SGD) was investigated at four sites covering a range of hydrogeological settings, namely Cockburn Sound (Australia); Shelter Island (USA); Ubatuba Bay (Brazil) and Flic-en-Flac Bay (Mauritius). At each of the sites, BGC was surveyed in the intertidal zone, and seepage meters were used for direct measurements of SGD flow rates. In the presence of detectable salinity gradients in the sediment, a negative correlation between SGD and BGC was recorded. The correlation is site-specific and is dependent on both the type of sediment and the mixing processes. For example, at Shelter Island the maximum mean flow rates were 65 cm d-1 at a BGC of ˜0 mS cm-1 while at Mauritius maximum mean flow rates were 364 cm d-1 at a BGC of ˜0 mS cm-1. BGC measurements are used to estimate SGD over a large scale, and to separate its fresh and saline components. Extrapolating BGC measurements throughout the study sites yields a total discharge of 2.91, 1.59, 7.16, and 25.4 103 m3 d-1 km-1 of shoreline with a freshwater fraction of 41, 24, 29, and 63% at Cockburn Sound, Shelter Island, Ubatuba Bay, and Flic-en-Flac Bay respectively. The results demonstrate that ground conductivity is a useful tracer to survey and separate freshwater and recirculated seawater component of SGD. The presented investigation is a subset within a series of experiments designed to compare different methods to investigate SGD co-organized and carried out by SCOR, LOICZ, IOC and IAEA.

  5. Comparison of Some Blast Vibration Predictors for Blasting in Underground Drifts and Some Observations

    Science.gov (United States)

    Bhagwat, Vaibhab Pramod; Dey, Kaushik

    2016-04-01

    Drilling and blasting are the most economical excavation techniques in underground drifts driven through hard rock formation. Burn cut is the most popular drill pattern, used in this case, to achieve longer advance per blast round. The ground vibration generated due to the propagation of blast waves on the detonation of explosive during blasting is the principal cause for structural and rock damage. Thus, ground vibration is a point of concern for the blasting engineers. The ground vibration from a blast is measured using a seismograph placed at the blast monitoring station. The measured vibrations, in terms of peak particle velocity, are related to the maximum charge detonated at one instant and the distance of seismograph from the blast point. The ground vibrations from a number of blast rounds of varying charge/delay and distances are monitored. A number of scaling factors of these dependencies (viz. Distance and maximum charge/delay) have been proposed by different researchers, namely, square root, cube root, CMRI, Langefors and Kihlstrom, Ghosh-Daemon, Indian standard etc. Scaling factors of desired type are computed for all the measured blast rounds. Regression analysis is carried out between the scaling factors and peak particle velocities to establish the coefficients of the vibration predictor equation. Then, the developed predictor equation is used for designing the blast henceforth. Director General of Mine Safety, India, specified that ground vibrations from eight to ten blast rounds of varying charge/delay and distances should be monitored to develop a predictor equation; however, there is no guideline about the type of scaling factor to be used. Further to this, from the statistical point of view, a regression analysis on a small sample population cannot be accepted without the testing of hypothesis. To show the importance of the above, in this paper, seven scaling factors are considered for blast data set of a hard-rock underground drift using burn

  6. Aspects of blast resistant masonry design

    Energy Technology Data Exchange (ETDEWEB)

    Volkman, D.E.

    1989-01-01

    Blast resistant design should be examined for building code incorporation, due to the potential of explosions occurring in an industrial society. Specifically, public and commercial structures of concrete masonry construction need additional building code criteria, since these buildings have high density populations to protect. Presently, blast resistant design is accomplished by using government published manuals, but these do not address industry standard construction. A design air blast load of 4.54 kg (10 lbs) of TNT, located 0.91 m (3 ft) above ground surface and 30.48 m (100 ft) from a structure should be considered standard criteria. This loading would be sufficient to protect against blast, resist progressive failure, and yet not be an economic impediment. Design details and adequate inspection must be observed to ensure blast resistant integrity. 10 refs., 3 figs., 1 tab.

  7. Ground measurements in Israel of solar events and their effects on the electrical parameters

    Science.gov (United States)

    Yaniv, Roy; Yair, Yoav; Price, Colin

    2017-04-01

    Solar events impact the Earth with fluxes of energetic particles or x-ray radiation and sometimes both together. The energetic particles induce pressure on the magnetosphere, generate enhanced and disruptive geomagnetic storms and deposit their energy to the Earth by altering the chemistry and changing the ionization in the upper atmosphere [Rycroft 2012]. Past measurements showed that in times of geomagnetic disturbances due to solar activity, an increase of the potential gradient (PG or Ez) and the conduction current (Jz) are observed on the day of the impact and on subsequent days [Cobb 1967, Reiter 1969, Nicoll and Harrison 2014, Elhalel et al., 2014, Mironova et al 2015]. We report on ground-based measurements of the Ez and Jz that were conducted continuously from two locations in Israel to measure the effect of solar events in low latitudes (30o35'N, 34o45'E 840m - Mitzpe Ramon and 33o18'N 35o47.2'E 2100m - Mt. Hermon) during days that were defined meteorologically as fair weather days. We present preliminary results of several case studies of solar events, that show a consistent increase of more than 50% in Ez during solar events compared to average fair weather values and to Kp and particles fluxes.

  8. Preliminary Study of Realistic Blast Impact on Cultured Brain Slices

    Science.gov (United States)

    2015-04-01

    hippocampal slice samples to better understand blast-induced brain damage. 15. SUBJECT TERMS RDX spheres , organotypic cultures of hippocampus, small...Preliminary Study of Realistic Blast Impact on Cultured Brain Slices by Thuvan Piehler, Rohan Banton, Lars Piehler, Richard Benjamin, Ray...Aberdeen Proving Ground, MD 21005-5066 ARL-TR-7197 April 2015 Preliminary Study of Realistic Blast Impact on Cultured Brain Slices Thuvan

  9. Blast Waves

    CERN Document Server

    Needham, Charles E

    2010-01-01

    The primary purpose of this text is to document many of the lessons that have been learned during the author’s more than forty years in the field of blast and shock. The writing therefore takes on an historical perspective, in some sense, because it follows the author’s experience. The book deals with blast waves propagating in fluids or materials that can be treated as fluids. It begins by distinguishing between blast waves and the more general category of shock waves. It then examines several ways of generating blast waves, considering the propagation of blast waves in one, two and three dimensions as well as through the real atmosphere. One section treats the propagation of shocks in layered gases in a more detailed manner. The book also details the interaction of shock waves with structures in particular reflections, progressing from simple to complex geometries, including planar structures, two-dimensional structures such as ramps or wedges, reflections from heights of burst, and three-dimensional st...

  10. 实验室认可中电热恒温鼓风干燥箱的期间核查%Laboratory Accreditation in the Electric Thermostat Blast Oven During Verification

    Institute of Scientific and Technical Information of China (English)

    王普力; 陈程

    2013-01-01

      本文以DHG-9140A电热恒温鼓风干燥箱为说明对象,按照《检测和校准实验室能力的通用要求》的相关规定,介绍了实验室认可中电热恒温鼓风干燥箱的期间核查操作规程及结果,为实验室认可中期间核查的开展提供了一定的依据。%This paper DHG-9140A electric thermostat blast oven as a description of the object , in accordance with the relevant provi-sions of the"General requirements for the capability of testing and calibration laboratories ", during the verification of operating procedures of the the Laboratory Accreditation electric thermostat blast oven and results provide the basis for conducting laboratory accreditation in during the verification carried out.

  11. 建筑电气安装及接地技术研究%Explore the Building Electrical Installation and Grounding Technology

    Institute of Scientific and Technical Information of China (English)

    刘劲松

    2014-01-01

    This article from the perspective of building elec-trical instal ation to analysis the basic principle and the key links of building electrical instal ation, and then discusses the main grounding technologies in the process of building electr-ical instal ation, in order to provide some meaningful reference for the construction electrical instal ation.%本文从建筑电气安装的角度,分析了建筑电气安装的一些基本的原理和关键环节,进而论述了建筑电气安装过程中的主要的接地技术,以期能够为建筑电气的安装提供有意义的借鉴。

  12. Mapping a Pristine Glaciofluvial Aquifer on the Canadian Shield Using Ground-Penetrating Radar and Electrical Resistivity Tomography

    Science.gov (United States)

    Graves, L. W.; Shirokova, V.; Bank, C.

    2013-12-01

    Our study aims to construct a 3D structural model of an unconfined pristine aquifer in Laurentian Hills, Ontario, Canada. The stratigraphy of the study site, which covers about 5400 square meters, features reworked glaciofluvial sands and glacial till on top of Canadian Shield bedrock. A network of 25 existing piezometers provides ground-truth. We used two types of geophysical surveys to map the water table and the aquifer basin. Ground-penetrating radar (GPR) collected 40 profiles over distances up to 140 meters using 200MHz and 400MHz antennas with a survey wheel. The collected radargrams show a distinct reflective layer, which can be mapped to outcrops of glacial till within the area. This impermeable interface forms the aquitard. Depths of the subsurface features were calculated using hyperbolic fits on the radargrams in Matlab by determining wave velocity then converting measured two-way-time to depth. Electrical resistivity was used to determine the water table elevations because the unconfined water table did not reflect the radar waves. 20 resistivity profiles were collected in the same area using Wenner-Alpha and dipole-dipole arrays with both 24 and 48 electrodes and for 0.5, 0.75, 1.0 and 2.0 meter spacing. The inverted resistivity models show low resistivity values (resistivity values (2000-6000 Ohm.m) above 1 to 2 meter depths. These contrasting resistivity values correspond to saturated and wet sand (lower resistivity) to dry sand (higher resistivity); a correlation we could verify with several bore-hole logs. The water table is marked on the resistivity profiles as a steep resistivity gradient, and the depth can be added to the comprehensive 3D model. This model also incorporates hydrogeological characteristics and geochemical anomalies found within the aquifer. Ongoing seasonal and annual monitoring of the aquifer using geophysical methods will bring a fourth dimension to our understanding of this dynamic system. GPR Profile with Glacial Till

  13. Assessment of MTI Water Temperature Retrievals with Ground Truth from the Comanche Peak Steam Electric Station Cooling Lake

    Energy Technology Data Exchange (ETDEWEB)

    Kurzeja, R.J.

    2002-12-09

    Surface water temperatures calculated from Multispectral Thermal Imager (MTI) brightness temperatures and the robust retrieval algorithm, developed by the Los Alamos National Laboratory (LANL), are compared with ground truth measurements at the Squaw Creek reservoir at the Comanche Peak Steam Electric Station near Granbury Texas. Temperatures calculated for thirty-four images covering the period May 2000 to March 2002 are compared with water temperatures measured at 10 instrumented buoy locations supplied by the Savannah River Technology Center. The data set was used to examine the effect of image quality on temperature retrieval as well as to document any bias between the sensor chip arrays (SCA's). A portion of the data set was used to evaluate the influence of proximity to shoreline on the water temperature retrievals. This study found errors in daytime water temperature retrievals of 1.8 C for SCA 2 and 4.0 C for SCA 1. The errors in nighttime water temperature retrievals were 3.8 C for SCA 1. Water temperature retrievals for nighttime appear to be related to image quality with the largest positive bias for the highest quality images and the largest negative bias for the lowest quality images. The daytime data show no apparent relationship between water temperature retrieval error and image quality. The average temperature retrieval error near open water buoys was less than corresponding values for the near-shore buoys. After subtraction of the estimated error in the ground truth data, the water temperature retrieval error was 1.2 C for the open-water buoys compared to 1.8 C for the near-shore buoys. The open-water error is comparable to that found at Nauru.

  14. 30 CFR 57.6605 - Isolation of blasting circuits.

    Science.gov (United States)

    2010-07-01

    ... NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Explosives Extraneous Electricity-Surface and Underground § 57.6605 Isolation of blasting circuits. Lead wires and blasting lines shall be isolated and insulated from power conductors, pipelines, and railroad tracks, and...

  15. Relationship of ground-level aerosol concentration and atmospheric electric field at three observation sites in the Arctic, Antarctic and Europe

    Science.gov (United States)

    Kubicki, Marek; Odzimek, Anna; Neska, Mariusz

    2016-09-01

    Aerosol number concentrations in the particle size range from 10 nm to 1 μm and vertical electric field strength in the surface layer was measured between September 2012 and December 2013 at three observation sites: mid-latitude station Swider, Poland, and, for the first time, in Hornsund in the Arctic, Spitsbergen, and the Antarctic Arctowski station in the South Shetland Islands. The measurements of aerosol concentrations have been performed simultaneously with measurements of the electric field with the aim to assess the local effect of aerosol on the electric field Ez near the ground at the three stations which at present form a network of atmospheric electricity observatories. Measurements have been made regardless of weather conditions at Swider and Arctowski station and mostly on fair-weather days at Hornsund station. The monthly mean particle number concentrations varied between 580 and 2100 particles cm- 3 at Arctowski, between 90 and 1270 particles cm- 3 in Hornsund, and between 6700 and 14,000 particles cm- 3 in the middle latitude station Swider. Average diurnal variations of the ground-level electric field Ez and particle number concentrations in fair-weather conditions were independent of each other for Arctowski and Hornsund stations. At Swider station the diurnal variation is usually characterized by an increase of aerosol concentration in the evening which results in the increased electric field. The assumption of neglecting the influence of varying aerosol concentration on the variation of the electric field in the polar regions, often adopted in studies, is confirmed here by the observations at Arctowski and Hornsund. The results of aerosol observations are also compared with modelled aerosol concentrations for global atmospheric electric circuit models.

  16. RESPONSE OF ELECTRICAL POWER SYSTEMS TO ELECTRO MAGNETIC EFFECTS OF NUCLEAR DETONATIONS

    Science.gov (United States)

    The response of a typical field army electrical power system to the electromagnetic pulse was measured at sufficient distance from ground zero to...prevent damage from blast and thermal effects. Twenty channels of a recording oscillograph were used to monitor selected variables from -15 seconds to 5...combination of effects such as prompt radiation and effects of the electromag netic pulse. A failure mechanism theory was postulated. Laboratory investigation

  17. Study of blasting vibrations in Sarcheshmeh copper mine

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Ground vibration is one of the side effects of blasting, in which way considerable amount of explosive energy is exhausted, and causes decrease in production and even decline in mine development workings. In this study, 57 recorded 3-C seismograms from 11 blasts in Sarcheshmeh copper mine, Kerman, Iran, are processed and analyzed. These data were recorded by digital seismograph PDAS-100 and analyzed by DADISP software. Finally, blasting parameters, such as explosive weight and type, distance between the structures and blasting site, blasting delays, affecting ground vibration are reviewed and their influence on peak particle velocity (PPV) are studied. Based on this study, suitable detonation delays and explosive type is determined. Considering these data, a graph of PPV versus scaled distance for Sarcheshmeh copper mine is prepared, by the help of which, safe distance for structures and accordingly explosive quantity could be determined.

  18. DNA Master File of Ground-Shock, Air-Blast, and Structure-Response Data. Volume 1. Archive Description and User’s Information

    Science.gov (United States)

    1975-11-01

    Representative (COR) during the early part of the program. Lt Col. D. Burgess was the COR for the remainder of the work. The initial effort was...were conducted near Pueblo, Colorado, to investigate ground response in clay-over- shale geologies. Event I was a 20-ton half-buried shot to be

  19. Occupational exposure to electric and magnetic fields during tasks at ground or floor level at 110 kV substations in Finland

    Science.gov (United States)

    Korpinen, Leena; Pääkkönen, Rauno

    2016-01-01

    The aim was to investigate occupational exposure to electric and magnetic fields during tasks at ground or floor level at 110 kV substations in Finland and to compare the measured values to Directive 2013/35/EU. Altogether, 347 electric field measurements and 100 magnetic field measurements were performed. The average value of all electric fields was 2.3 kV/m (maximum 6.4 kV/m) and that of magnetic fields was 5.8 µT (maximum 51.0 µT). It can be concluded that the electric and magnetic field exposure at ground or floor level is typically below the low action levels of Directive 2013/35/EU. The transposition of the directive will not create new needs to modify the work practice of the evaluated tasks, which can continue to be performed as before. However, for workers with medical implants, the exposure may be high enough to cause interference. PMID:27075421

  20. Lightning rod ionizing natural ionca - Ionic electrode active trimetallictriac of grounding - Definitive and total solution against 'blackouts' and electrical faults generated by atmospheric charges (lightning)

    Energy Technology Data Exchange (ETDEWEB)

    Cabareda, Luis

    2010-09-15

    The Natural Ionizing System of Electrical Protection conformed by: Lightning Rod Ionizing Natural Ionca and Ionic Electrode Active Trimetallic Triac of Grounding offers Total Protection, Maximum Security and Zero Risk to Clinics, Hospitals, Integral Diagnostic Center, avoiding ''the burning'' of Electronics Cards; Refineries, Tanks and Stations of Fuel Provision; Electrical Substations, Towers and Transmission Lines with transformer protection, motors, elevators, A/C, mechanicals stairs, portable and cooling equipment, electrical plants, others. This New High Technology is the solution to the paradigm of Benjamin Franklin and it's the mechanism to end the 'Blackouts' that produces so many damages and losses throughout the world.

  1. An application of regression model for evaluation of blast vibration in an opencast coal mine: a case analysis

    Energy Technology Data Exchange (ETDEWEB)

    Brahma, K.C.; Pal, B.K.; Das, C. [CMPDI, Bhubaneswar (India)

    2005-07-01

    Different models of vibration studies are examined. A case analysis to determine the parameters governing the prediction of blast vibration in an opencast coal mine is described. A regression model was developed to evaluate peak particle velocity (PPV) of the blast. The results are applicable to forecasting ground vibration before blasting and to the design of various parameters in controlled blasting. 16 refs., 1 fig., 1 tab.

  2. Calculation of driling and blasting parameters in blasting performance

    OpenAIRE

    Dambov, Risto; Karanakova Stefanovska, Radmila; Dambov, Ilija

    2015-01-01

    In all mining technology drilling and blasting parameters and works are one of the main production processes at each mine. The parameters of drilling and blasting and explosives consumption per ton of blasting mass are define economic indicators of any blasting no matter for what purpose and where mining is performed. The calculation of rock blasting should always have in mind that the methodology of calculation of all drilling and blasting parameters in blasting performance are performed for...

  3. Static electric multipole susceptibilities of the relativistic hydrogen-like atom in the ground state: Application of the Sturmian expansion of the generalized Dirac-Coulomb Green function

    CERN Document Server

    Szmytkowski, Radosław

    2016-01-01

    The ground state of the Dirac one-electron atom, placed in a weak, static electric field of definite $2^{L}$-polarity, is studied within the framework of the first-order perturbation theory. The Sturmian expansion of the generalized Dirac-Coulomb Green function [R. Szmytkowski, J. Phys. B 30 (1997) 825, erratum: 30 (1997) 2747] is used to derive closed-form analytical expressions for various far-field and near-nucleus static electric multipole susceptibilities of the atom. The far-field multipole susceptibilities --- the polarizabilities $\\alpha_{L}$, electric-to-magnetic cross-susceptibilities $\\alpha_{\\mathrm{E}L\\to\\mathrm{M}(L\\mp1)}$ and electric-to-toroidal-magnetic cross-susceptibilities $\\alpha_{\\mathrm{E}L\\to\\mathrm{T}L}$ --- are found to be expressible in terms of one or two non-terminating generalized hypergeometric functions ${}_{3}F_{2}$ with the unit argument. Counterpart formulas for the near-nucleus multipole susceptibilities --- the electric nuclear shielding constants $\\sigma_{\\mathrm{E}L\\to\\m...

  4. Measured electric and magnetic fields from an unusual cloud-to-ground lightning flash containing two positive strokes followed by four negative strokes

    Science.gov (United States)

    Jerauld, J. E.; Uman, M. A.; Rakov, V. A.; Rambo, K. J.; Jordan, D. M.; Schnetzer, G. H.

    2009-10-01

    We present electric and magnetic fields measured at multiple stations between about 300 and 800 m of a cloud-to-ground "bipolar" lightning flash containing two initial positive strokes, separated in time by 53 ms and striking ground at two locations separated by about 800 m, followed by four negative strokes that traversed the same path as the second positive stroke. The leader electric field durations for the positive first, positive second, and negative third strokes were about 120 ms, 35 ms, and 1 ms, respectively. The first-stroke leader electric field changes measured at five stations ranged from about +16 to +35 kV/m, the second stroke +8 to +13 kV/m, and the third stroke -0.9 to -1.8 kV/m (atmospheric electricity sign convention). The microsecond-scale return stroke waveforms of the first and second (positive) strokes exhibited a similar "slow-front/fast-transition" to those observed for close negative first strokes. The peak rate-of-change of the positive first stroke electric field normalized to 100 km was about 20 V m-1μs-1, similar to the values observed for close negative first strokes. The positive second stroke was followed by a long continuing current of duration at least 400 ms, while the positive first stroke had a total current duration of only about 1 ms. All four negative strokes were followed by long continuing current, with durations ranging from about 70 ms to about 230 ms. The overall flash duration was about 1.5 s.

  5. Blasting response of the Eiffel Tower

    Science.gov (United States)

    Horlyck, Lachlan; Hayes, Kieran; Caetano, Ryan; Tahmasebinia, Faham; Ansourian, Peter; Alonso-Marroquin, Fernando

    2016-08-01

    A finite element model of the Eiffel Tower was constructed using Strand7 software. The model replicates the existing tower, with dimensions justified through the use of original design drawings. A static and dynamic analysis was conducted to determine the actions of the tower under permanent, imposed and wind loadings, as well as under blast pressure loads and earthquake loads due to an explosion. It was observed that the tower utilises the full axial capacity of individual members by acting as a `truss of trusses'. As such, permanent and imposed loads are efficiently transferred to the primary columns through compression, while wind loads induce tensile forces in the windward legs and compressive forces in the leeward. Under blast loading, the tower experienced both ground vibrations and blast pressures. Ground vibrations induced a negligibly small earthquake loading into the structure which was ignored in subsequent analyses. The blast pressure was significant, and a dynamic analysis of this revealed that further research is required into the damping qualities of the structure due to soil and mechanical properties. In the worst case scenario, the blast was assumed to completely destroy several members in the adjacent leg. Despite this weakened condition, it was observed that the tower would still be able to sustain static loads, at least for enough time for occupant evacuation. Further, an optimised design revealed the structure was structurally sound under a 46% reduction of the metal tower's mass.

  6. Prediction of vibration level in tunnel blasting; Tonneru kusshin happa ni yotte reiki sareru shindo no reberu yosoku ho

    Energy Technology Data Exchange (ETDEWEB)

    Hirata, A. [Kumamoto Industries Univ, Kumamoto (Japan); Yamamoto, M. [Asahi Chemical Industry Co. Ltd., Tokyo (Japan); Inaba, C. [Nishimatsu Construction Co. Ltd., Kanagawa (Japan); Kaneko, K. [Hokkaido Univ (Japan)

    1997-08-01

    For avoiding the generation of public hazard due to ground vibration causes by blasting in tunneling, it is important to devise a blasting method for ensuring the level of the ground vibration caused thereby under a limit, and an exact predication of ground vibration before blasting is desirable. In this study, the characteristics of the ground vibration caused by tunnel blasting are analyzed, and a summary of amplitude spectra calculating method is described. A theoretical analysis method for predicting the vibration level is proposed based on spectrum-multiplicative method. Vibration caused by multistage blasting in tunneling is most strong and deemed as important. When observing the process of elastic wave motion caused by multistage blasting being measured, the process can be divided into three element processes in frequency area as vibration source spectrum, transmission attenuation spectrum and frequency response function vibrating test, and, with the multiplication of them, the amplitude spectra at an observation portion can be estimated. 12 refs., 12 figs.

  7. Design of a grounding network in electrical substations. Materials and formulas the most used; Diseno de redes de tierra en subestaciones electricas. Materiales y formulas mas utilizadas

    Energy Technology Data Exchange (ETDEWEB)

    Raull Martin, J. [Facultad de Ingenieria, UNAM, Mexico, D.F. (Mexico)

    2000-09-01

    The purpose of this paper is to present a summarized version of the different types of construction of grounding systems, as well as their materials and formulas, which are necessary and useful for the design and building of a grounding network for medium to high voltage facilities. A description is also made of how to determine the electrical resistivity of subsoil layers with different physical characteristics. Several illustrative examples are also solved in the paper. [Spanish] El proposito de este articulo es presentar de manera resumida los diferentes tipos de construccion de los sistemas de tierra, asi como sus materiales y formulas, los cuales son necesarios y utiles para el diseno y edificacion de una red de tierra para instalaciones de mediana y alta tension. Se describe tambien la obtencion de las diferentes resistividades que presenta los terrenos con diversas caracteristicas fisicas. Asimismo, se solucionan ejercicios ilustrativos a lo largo del articulo.

  8. Methodology for evaluating the grounding system in electrical substations; Metodologia para la evaluacion del sistema de puesta a tierra en subestaciones electricas

    Energy Technology Data Exchange (ETDEWEB)

    Torrelles Rivas, L.F [Universidad Nacional Experimental Politecnica: Antonio Jose de Sucre (UNEXPO), Guayana, Bolivar (Venezuela)]. E-mail: torrellesluis@gmail.com; Alvarez, P. [Petroleos de Venezuela S.A (PDVSA), Maturin, Monagas (Venezuela)]. E-mail: alvarezph@pdvsa.com

    2013-03-15

    The present work proposes a methodology for evaluating grounding systems in electrical substations from medium and high voltage, in order to diagnose the state of the elements of the grounding system and the corresponding electrical variables. The assessment methodology developed includes a visual inspection phase to the elements of the substation. Then, by performing measurements and data analysis, the electrical continuity between the components of the substation and the mesh ground is verified, the soil resistivity and resistance of the mesh. Also included in the methodology the calculation of the step and touch voltage of the substation, based on the criteria of the International IEEE standards. We study the case of the 115 kV Pirital Substation belonging to PDVSA Oriente Transmission Network. [Spanish] En el presente trabajo se plantea una metodologia para la evaluacion de sistemas de puesta a tierra en subestaciones electricas de media y alta tension, con la finalidad de diagnosticar el estado de los elementos que conforman dicho sistema y las variables electricas correspondientes. La metodologia de evaluacion desarrollada incluye una fase de inspeccion visual de los elementos que conforman la subestacion. Luego, mediante la ejecucion de mediciones y analisis de datos, se verifica la continuidad electrica entre los componentes de la subestacion y la malla de puesta a tierra, la resistividad del suelo y resistencia de la malla. Se incluye tambien en la metodologia el calculo de las tensiones de paso y de toque de la subestacion, segun lo fundamentado en los criterios de los estandares Internacionales IEEE. Se estudia el caso de la Subestacion Pirital 115 kV perteneciente a la Red de Transmision de PDVSA Oriente.

  9. A new experimental approach for characterizing the internal trapped charge and electric field build up in ground-coated insulators during their e sup - irradiation

    CERN Document Server

    Jbara, O; Belhaj, M; Cazaux, J; Rau, E I; Filippov, M; Andrianov, M V

    2002-01-01

    An original method is proposed to investigate the dynamical trapping properties of bulk insulators during their irradiation by keV electrons when they are coated with a grounded metallic film. This method is based on the measurement of the displacement current and it allows to evaluate time constants for charging and discharging the dielectric as well as to evaluate the electric field build up and trapped charge density below the coating. This method is illustrated by the estimate of the charging and discharging time constants in e sup - irradiated PMMA and the estimate of the magnitude of the electric field which drives the migration of the mobile ions in e sup - irradiated glasses.

  10. Theoretical Electric Dipole Moments and Dissociation Energies for the Ground States of GaH-BrH

    Science.gov (United States)

    Pettersson, Lars G. M.; Langhoff, Stephen R.

    1986-01-01

    Reliable experimental diople moments are available for the ground states of SeH and BrH whereas no values have been reported for GaH and AsH a recently reported experimental dipole moment for GeH of 1.24 + or -0.01 D has been seriously questioned, and a much lower value of, 0.1 + or - 0.05 D, suggested. In this work, we report accurate theoretical dipole moments, dipole derivatives, dissociation energies, and spectroscopic constants (tau(sub e), omega(sub e)) for the ground states of GaH through BrH.

  11. Ground-based instrumentation for measurements of atmospheric conduction current and electric field at the South Pole

    Science.gov (United States)

    Byrne, G. J.; Benbrook, J. R.; Bering, E. A.; Few, A. A.; Morris, G. A.; Trabucco, W. J.; Paschal, E. W.

    1993-01-01

    Attention is given to instruments constructed to measure the atmospheric conduction current and the atmospheric electric field - two fundamental parameters of the global-electric circuit. The instruments were deployed at the Amundsen-Scott South Pole Station in January 1991 and are designed to operate continuously for up to one year without operator intervention. The atmospheric current flows into one hemisphere, through the electronics where it is measured, and out the other hemisphere. The electric field is measured by a field mill of the rotating dipole type. Sample data from the first days of operation at the South Pole indicate variations in the global circuit over time scales from minutes to hours to days.

  12. Ground-penetrating radar and electrical resistivity tomography for mapping bedrock topography and fracture zones: a case study in Viru-Nigula, NE Estonia

    Directory of Open Access Journals (Sweden)

    Ivo Sibul

    2017-06-01

    Full Text Available The Geological Base Map (GBM, presenting an elongated buried valley running beneath the Varudi bog, triggered the geophysical studies near Viru-Nigula borough in northeastern Estonia. After the Geological Survey of Estonia had compiled the GBM map set, the course and extent of the valley still remained indistinct. Principally the morphology of the Varudi valley had been determined just by one borehole characterizing the 30 m thick Quaternary succession within the valley. The thickness of Quaternary sediments is, however, just a few metres in adjacent boreholes. We used ground-penetrating radar and electrical resistivity tomography (ERT for acquiring extra knowledge about the extent and morphology of the Varudi structure. Ground-penetrating radar enabled us to specify the thickness and composition of Quaternary deposits, and to recognize dislocations of the bedrock blocks. As the radar images provided information on the topmost ~4 m only, ERT (Wenner and Wenner–Schlumberger arrays was applied to define deeper, down to 40 m, electrical resistivity anomalies. The ERT studies revealed two fracture zones where regular Ordovician carbonate beds have been crushed and replaced by Quaternary sediments. The Varudi valley coincides with the southern zone. Both fracture zones probably acted as groundwater flow channels and sediment pathways in the Late Pleistocene, and hence supported the creation of the Varudi bog.

  13. Comparative regional-scale soil salinity assessment with near-ground apparent electrical conductivity and remote sensing canopy reflectance

    Science.gov (United States)

    Soil salinity is recognized worldwide as a major threat to agriculture, particularly in arid and semi-arid regions. Farmers and decision makers need updated and accurate maps of salinity in agronomically and environmentally relevant ranges (i.e., salinity is measured as electrical...

  14. An In-Depth Look at Ground Source Heat Pumps and Other Electric Loads in Two GreenMax Homes

    Energy Technology Data Exchange (ETDEWEB)

    Puttagunta, Srikanth [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States); Shapiro, Carl [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States)

    2012-04-01

    Building America research team Consortium for Advanced Residential Buildings (CARB) partnered with WPPI Energy to answer key research questions on in-field performance of ground-source heat pumps and lighting, appliance, and miscellaneous loads (LAMELs) through extensive field monitoring at two WPPI GreenMax demonstration homes in Wisconsin. These two test home evaluations provided valuable data on the true in-field performance of various building mechanical systems and LAMELs.

  15. Methods and applications of electrical simulation in ground-water studies in the lower Arkansas and Verdigris River Valleys, Arkansas and Oklahoma

    Science.gov (United States)

    Bedinger, M.S.; Reed, J.E.; Wells, C.J.; Swafford, B.F.

    1970-01-01

    The Arkansas River Multiple-Purpose Plan will provide year-round navigation on the Arkansas River from near its mouth to Muskogee, Okla., and on the Verdigris River from Muskogee to Catoosa, Okla. The altered regimen in the Arkansas and Verdigris Rivers will affect ground-water conditions in the adjacent alluvial aquifers. In 1957 the U.S. Geological Survey and U.S. Army Corps of Engineers entered into a cooperative agreement for a comprehensive ground-water study of the lower Arkansas and Verdigris River valleys. At the request of the Corps of Engineers, the Geological Survey agreed to provide (1) basic ground-water data before, during, and after construction of the Multiple-Purpose Plan and (2) interpretation and projections of postconstruction ground-water conditions. The data collected were used by the Corps of Engineers in preliminary foundation and excavation estimates and by the Geological Survey as the basis for defining the hydrologic properties of, and the ground-water conditions in, the aquifer. The projections of postconstruction ground-water conditions were used by the Corps of Engineers in the planning, design, construction, and operation of the Multiple-Purpose Plan. Analysis and projections of ground-water conditions were made by use of electrical analog models. These models use the analogy between the flow of electricity in a resistance-capacitance circuit and the flow of a liquid in a porous and permeable medium. Verification provides a test of the validity of the analog to perform as the aquifer would, within the range of historic forces. The verification process consists of simulating the action of historic forces which have acted upon the aquifer and of duplicating the aquifer response with the analog. The areal distribution of accretion can be treated as an unknown and can be determined by analog simulation of the piezometric surface in an aquifer. Comparison of accretion with depth to piezometric surface below land surface shows that

  16. Ground-truthing electrical resistivity methods in support of submarine groundwater discharge studies: Examples from Hawaii, Washington, and California

    Science.gov (United States)

    Johnson, Cordell; Swarzenski, Peter W.; Richardson, Christina M.; Smith, Christopher G.; Kroeger, Kevin D.; Ganguli, Priya M.

    2015-01-01

    Submarine groundwater discharge (SGD) is an important conduit that links terrestrial and marine environments. SGD conveys both water and water-borne constituents into coastal waters, where these inflows may impact near-shore ecosystem health and sustainability. Multichannel electrical resistivity techniques have proven to be a powerful tool to examine scales and dynamics of SGD and SGD forcings. However, there are uncertainties both in data aquisition and data processing that must be addressed to maximize the effectiveness of this tool in estuarine or marine environments. These issues most often relate to discerning subtle nuances in the flow of electricity through variably saturated media that can also be highly conductive (i.e., seawater).

  17. A microbial fuel cell in contaminated ground delineated by electrical self-potential and normalized induced polarization data

    Science.gov (United States)

    Doherty, R.; Kulessa, B.; Ferguson, A. S.; Larkin, M. J.; Kulakov, L. A.; Kalin, R. M.

    2010-09-01

    There is a growing interest in the use of geophysical methods to aid investigation and monitoring of complex biogeochemical environments, for example delineation of contaminants and microbial activity related to land contamination. We combined geophysical monitoring with chemical and microbiological analysis to create a conceptual biogeochemical model of processes around a contaminant plume within a manufactured gas plant site. Self-potential, induced polarization and electrical resistivity techniques were used to monitor the plume. We propose that an exceptionally strong (>800 mV peak to peak) dipolar SP anomaly represents a microbial fuel cell operating in the subsurface. The electromagnetic and electrical geophysical data delineated a shallow aerobic perched water body containing conductive gasworks waste which acts as the abiotic cathode of microbial fuel cell. This is separated from the plume below by a thin clay layer across the site. Microbiological evidence suggests that degradation of organic contaminants in the plume is dominated by the presence of ammonium and its subsequent degradation. We propose that the degradation of contaminants by microbial communities at the edge of the plume provides a source of electrons and acts as the anode of the fuel cell. We hypothesize that ions and electrons are transferred through the clay layer that was punctured during the trial pitting phase of the investigation. This is inferred to act as an electronic conductor connecting the biologically mediated anode to the abiotic cathode. Integrated electrical geophysical techniques appear well suited to act as rapid, low cost sustainable tools to monitor biodegradation.

  18. INFLUENCE OF THE MODERN SYSTEMS OF THE BLAST STEEL-FURNACE ELECTRICAL PARAMETERS CONTROL ON CAPACITY AND TECHNICAL AND ECONOMICAL INDICES OF MELTING

    Directory of Open Access Journals (Sweden)

    D. N. Andrianov

    2006-01-01

    Full Text Available The reduction of time under the current, electric energy rate, electrodes rate at working of arc steel-furnace with new transformer of capacity 95 MBA and with regulating system SIMELT-AC-NEC are noted.

  19. a Finite Difference Numerical Model for the Propagation of Finite Amplitude Acoustical Blast Waves Outdoors Over Hard and Porous Surfaces

    Science.gov (United States)

    Sparrow, Victor Ward

    1990-01-01

    This study has concerned the propagation of finite amplitude, i.e. weakly non-linear, acoustical blast waves from explosions over hard and porous media models of outdoor ground surfaces. The nonlinear acoustic propagation effects require a numerical solution in the time domain. To model a porous ground surface, which in the frequency domain exhibits a finite impedance, the linear phenomenological porous model of Morse and Ingard was used. The phenomenological equations are solved in the time domain for coupling with the time domain propagation solution in the air. The numerical solution is found through the method of finite differences. The second-order in time and fourth -order in space MacCormack method was used in the air, and the second-order in time and space MacCormack method was used in the porous medium modeling the ground. Two kinds of numerical absorbing boundary conditions were developed for the air propagation equations to truncate the physical domain for solution on a computer. Radiation conditions first were used on those sides of the domain where there were outgoing waves. Characteristic boundary conditions secondly are employed near the acoustic source. The numerical model agreed well with the Pestorius algorithm for the propagation of electric spark pulses in the free field, and with a result of Pfriem for normal plane reflection off a hard surface. In addition, curves of pressure amplification versus incident angle for waves obliquely incident on the hard and porous surfaces were produced which are similar to those in the literature. The model predicted that near grazing finite amplitude acoustic blast waves decay with distance over hard surfaces as r to the power -1.2. This result is consistent with the work of Reed. For propagation over the porous ground surface, the model predicted that this surface decreased the decay rate with distance for the larger blasts compared to the rate expected in the linear acoustics limit.

  20. BLAST: A balloon-borne, large-aperture, submillimetre telescope

    Science.gov (United States)

    Wiebe, Donald Victor

    BLAST is a balloon-borne large-aperture, submillimetre telescope, which makes large area (1--200 square degree) surveys of Galactic and extragalactic targets. Since BLAST observes in the stratosphere, it is able to make broad-band observations between 200 mum and 550 mum which are difficult or impossible to perform from the ground. BLAST has been designed to probe star formation both in the local Galaxy and in the high redshift (z = 1--4) universe. Because BLAST is flown on an unmanned stratospheric balloon platform, it has been designed to be able to operate autonomously, without needing operator intervention to perform its scientific goals. This thesis includes an overview of the design of the BLAST platform, with emphasis on the command and control systems used to operate the telescope. BLAST has been flown on two long-duration balloon flights. The first of these, from Esrange, Sweden in June of 2005, acquired ˜70 hours of primarily Galactic data. During the second flight, from Willy Field, Antarctica in December of 2006, BLAST acquired ˜225 hours of both Galactic and extragalactic data. Operational performance of the platform during these two flights is reviewed, with the goal of providing insight on how future flights can be improved. Reduction of the data acquired by these large-format bolometer arrays is a challenging procedure, and techniques developed for BLAST data reduction are reviewed. The ultimate goal of this reduction is the generation of high quality astronomical maps which can be used for subsequent portions of data analysis. This thesis treats, in detail, the iterative, maximum likelihood map maker developed for BLAST. Results of simulations performed on the map maker to characterise its ability to reconstruct astronomical signals are presented. Finally, astronomical maps produced by this map maker using real data acquired by BLAST are presented, with a discussion on non-physical map pathologies resulting from the data reduction pipeline and

  1. Dry ice blasting

    Science.gov (United States)

    Lonergan, Jeffrey M.

    1992-04-01

    As legal and societal pressures against the use of hazardous waste generating materials has increased, so has the motivation to find safe, effective, and permanent replacements. Dry ice blasting is a technology which uses CO2 pellets as a blasting medium. The use of CO2 for cleaning and stripping operations offers potential for significant environmental, safety, and productivity improvements over grit blasting, plastic media blasting, and chemical solvent cleaning. Because CO2 pellets break up and sublime upon impact, there is no expended media to dispose of. Unlike grit or plastic media blasting which produce large quantities of expended media, the only waste produced by CO2 blasting is the material removed. The quantity of hazardous waste produced, and thus the cost of hazardous waste disposal is significantly reduced.

  2. Electric Control System Grounding Analysis of Railway Heavy Duty Track Maintenance Machine%铁路大型养路机械电气控制系统接地分析

    Institute of Scientific and Technical Information of China (English)

    程连飞

    2011-01-01

    分析了铁路大型养路机械电气系统的接地方式,阐述了因接地不当对电气控制系统造成的影响,并提出了改进措施.合理的接地能够改善大型养路机械的作业精度,并提高电气控制系统的可靠性和稳定性.%Grounding styles of electric system for the railway heavy duty tracl maintenance machine were analyzed,and impac due to improper grounding as well as improving mesaures of electric control system was described.It was proved that resonable grounding can improve operation accuracy of the railway heavy duty track maintenance machine and the reliability and stability of the electric control system.

  3. Electric field modulation of the tetragonal domain orientation revealed in the magnetic ground state of quantum paraelectric EuTiO3

    Science.gov (United States)

    Petrović, A. P.; Kato, Y.; Sunku, S. S.; Ito, T.; Sengupta, P.; Spalek, L.; Shimuta, M.; Katsufuji, T.; Batista, C. D.; Saxena, S. S.; Panagopoulos, C.

    2013-02-01

    We present a study of the thermodynamic and magnetic properties of single-crystal EuTiO3. Signatures of metastability are visible in the heat capacity below the cubic-tetragonal phase transition at 283 K, supporting the evidence for a mismatch between long and short range structural order from previous x-ray diffraction studies. Employing the anisotropic magnetization as an indirect structural probe, we confirm the emergence of multiple orthogonal domains at low temperature. Torque magnetometry is capable of revealing the nature and temperature dependence of the magnetic anisotropy in spite of the domain misalignment; we hence deduce that tetragonal EuTiO3 enters an easy-axis antiferromagnetic phase at 5.6 K, with a first-order phase transition to an easy-plane ground state below 3 K. Our experimentally determined magnetic phase diagram is accurately reproduced by a three-dimensional (3D) anisotropic Heisenberg spin model. Furthermore, we demonstrate that electric field cooling acts to suppress this orientational disorder by realigning the domains due to the strong coupling between electric fields and lattice dipoles characteristic of paraelectric materials.

  4. Modeling the high-latitude ground response to the excitation of the ionospheric MHD modes by atmospheric electric discharge

    Science.gov (United States)

    Fedorov, E.; Mazur, N.; Pilipenko, V.; Baddeley, L.

    2016-11-01

    The ionospheric Alfvén resonator (IAR) and fast magnetosonic (FMS) waveguide, which can trap the electromagnetic wave energy in the range from fractions of Hz to several Hz, are characteristic features of the upper ionosphere. Their role in the electromagnetic impulsive coupling between atmospheric discharge processes and the ionosphere can be elucidated with a proper model. The presented model is based on numerical solution of coupled wave equations for electromagnetic modes in the ionosphere and atmosphere in a realistic ionosphere modeled with the use of IRI (International Reference Ionosphere) vertical profiles. The geomagnetic field is supposed to be nearly vertical, so the model can be formally applied to high latitudes, though the main features of ground ULF structure will be qualitatively similar at middle latitudes as well. The modeling shows that during the lightning discharge a coupled wave system comprising IAR and MHD waveguide is excited. Using the model, the spatial structure, frequency spectra, and polarization parameters have been calculated at various distances from a vertical dipole. In the lightning proximity (about several hundred kilometer) only the lowest IAR harmonics are revealed in the radial magnetic component spectra. At distances >800 km the multiband spectral structure is formed predominantly by harmonics of FMS waveguide modes. The model predictions do not contradict the results of search coil magnetometer observations on Svalbard; however, the model validation demands more dedicated experimental studies.

  5. Realization of Multi-Stable Ground States in a Nematic Liquid Crystal by Surface and Electric Field Modification

    Science.gov (United States)

    Gwag, Jin Seog; Kim, Young-Ki; Lee, Chang Hoon; Kim, Jae-Hoon

    2015-06-01

    Owing to the significant price drop of liquid crystal displays (LCDs) and the efforts to save natural resources, LCDs are even replacing paper to display static images such as price tags and advertising boards. Because of a growing market demand on such devices, the LCD that can be of numerous surface alignments of directors as its ground state, the so-called multi-stable LCD, comes into the limelight due to the great potential for low power consumption. However, the multi-stable LCD with industrial feasibility has not yet been successfully performed. In this paper, we propose a simple and novel configuration for the multi-stable LCD. We demonstrate experimentally and theoretically that a battery of stable surface alignments can be achieved by the field-induced surface dragging effect on an aligning layer with a weak surface anchoring. The simplicity and stability of the proposed system suggest that it is suitable for the multi-stable LCDs to display static images with low power consumption and thus opens applications in various fields.

  6. LTC vacuum blasting maching (concrete): Baseline report: Greenbook (Chapter)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-07-31

    The LTC shot blast technology was tested and is being evaluated at Florida International University (FIU) as a baseline technology. In conjuction with FIU`s evaluation of efficiency and cost, this report covers the evaluation conducted for safety and health issues. It is a commercially available technology and has been used for various projects at locations throughout the country. The LTC 1073 Vacuum Blasting Machine uses a high-capacity, direct-pressure blasting system which incorporates a continuous feed for the blast media. The blast media cleans the surface within the contained brush area of the blast. It incorporates a vacuum system which removes dust and debris from the surface as it is blasted. The safety and health evaluation during the testing demonstration focused on two main areas of exposure: dust and noise. Dust exposure during maintenance activities was minimal, but due to mechanical difficulties dust monitoring could not be conducted during operation. Noise exposure was significant. Further testing for each of these exposures is recommended because of the outdoor environment where the testing demonstration took place. This may cause the results to be inaccurate. It is feasible that the dust and noise levels will be higher in an enclosed environment. In addition, other safety and health issues found were ergonomics, heat stress, tripping hazards, electrical hazards, lockout/tagout, and arm-hand vibration.

  7. Soil bulk electrical resistivity and forage ground cover: nonlinear models in an alfalfa (Medicago sativa L. case study

    Directory of Open Access Journals (Sweden)

    Roberta Rossi

    2015-12-01

    Full Text Available Alfalfa is a highly productive and fertility-building forage crop; its performance, can be highly variable as influenced by within-field soil spatial variability. Characterising the relations between soil and forage- variation is important for optimal management. The aim of this work was to model the relationship between soil electrical resistivity (ER and plant productivity in an alfalfa (Medicago sativa L. field in Southern Italy. ER mapping was accomplished by a multi-depth automatic resistivity profiler. Plant productivity was assessed through normalised difference vegetation index (NDVI at 2 dates. A non-linear relationship between NDVI and deep soil ER was modelled within the framework of generalised additive models. The best model explained 70% of the total variability. Soil profiles at six locations selected along a gradient of ER showed differences related to texture (ranging from clay to sandy-clay loam, gravel content (0 to 55% and to the presence of a petrocalcic horizon. Our results prove that multi-depth ER can be used to localise permanent soil features that drive plant productivity.

  8. Technique for determining the channel expansion rate at the stage of electrical breakdown using a grounded intercepting ring

    Science.gov (United States)

    Apollonov, V. V.; Pletnev, N. V.

    2016-11-01

    A method is described that allows one to study the conductivity dynamics of a channel produced by explosion of a wire at the stage of electrical breakdown. Experimental data have been presented for the expansion rate of the conductivity channel in extended (up to 1.9 m long) arbitrarily shaped gapes that were produced by an exploding copper wire 90 µm in diameter. The initial stored energy and applied voltage were, respectively, 2.7-3.7 kJ and 8-10 kV. It has been shown that the expansion rate of the conductivity channel coincides with the propagation rate of a shock wave and is inversely proportional to the square root of its radius and propagation time. The radius of the shock wave is a linear function of the square root of its propagation rate. Experimental data are in satisfactory agreement with the calculated results obtained by Lin [18] in terms of the model of an intense shock wave. It has been shown that the diameter of the conductivity channel depends on the position of the trailing edge of the shock wave.

  9. A Testing Ground for Polarized Maser Transport: Multi-Epoch Analysis of a π/2 Electric Vector Rotation

    Science.gov (United States)

    Tobin, Taylor; Kemball, Athol J.

    2017-01-01

    The near circumstellar environment (NCSE) around Asymptotic Giant Branch (AGB) stars is chaotic, exhibiting shocks, turbulence, velocity gradients, and a potentially dynamically significant magnetic field (Vlemmings et al. 2005). Very Long Baseline Interferometry (VLBI) of masers emanating from these environments can provide sub-milliarcsecond angular resolution of the NCSE (Kemball 2002). Solidifying the origin of the polarization in these masers may be the key to understanding the magnitude and behavior of these stars' magnetic fields (eg. Goldreich et al. 1973; Elitzur 1996). However, other theories of polarized maser transport do not rely heavily on the magnetic field; some are more dependent on anisotropic pumping (Elitzur 1996; Watson 2009) or anisotropic resonant scattering (Asensio Ramos et al. 2005; Houde 2014). One optimal test of these theories is their ability to account for a π/2 rotation of the Electric Vector Position Angle (EVPA) observed in some maser features. The profile of linear polarization across such a feature varies with the generating mechanism. In this study, we utilize multi-epoch observations of ν=1, J=1-0 SiO maser emission around TX Cam (Diamond & Kemball 2003; Kemball et al. 2009; Gonidakis et al. 2010) to analyze a single feature with a π/2 rotation that persisted for five epochs and compare it to the behavior expected according to various theories of maser polarization. In addition, we analyze the low levels of circular polarization - now achievable due to recent improvements in millimeter-wavelength circular polarization reduction (Kemball & Richter 2011) - and compare their correlation with other parameters to further test these polarization generation theories.

  10. Predicting the Impact of Rock Blasting on Building Structures at Awunakrom in the Ahanta West District of Ghana

    Directory of Open Access Journals (Sweden)

    K.J. Bansah

    2014-07-01

    Full Text Available Blasting is an important process after drilling is completed in hard rock mining. It involves placing explosives in drill holes and detonating them to cause explosion. The energy released during this process fragments the rocks into sizes for desired end use. The detonation of these explosives may produce undesirable effects such as ground vibration which is capable of causing damage to building structures. It is therefore, necessary to conduct blast impact studies to determine potential impact of blast induced ground vibration prior to mining and establish remediation techniques. Blast impact study was conducted at Awunakrom in the Ahanta West District of Ghana. Building structures within the study area were mapped and characterized. A blast impact prediction model was also generated. Blast induced vibrations that may propagate from the Father Brown pit of Golden Star Wassa Limited using various instantaneous charges were determined. It was found that bench blasting at the Father Brown pit has a potential of causing damage to building structures within the Awunakrom community if the maximum instantaneous charge adopted at the southernmost periphery of the pit exceeds 30 kg. It was therefore, recommended that all bench blast conducted at the southern periphery of the Father Brown pit should adopt a maximum instantaneous charge of 30 kg to avert any potential blast damage. However, variable instantaneous charges of more than 30 kg can be adopted as the blast location moves towards the northern periphery.

  11. International Aerospace and Ground Conference on Lightning and Static Electricity (ICOLSE) (10th) and the Congres International Aeronautiq (17th) Held in Paris (France) on 10-13 June 1985

    Science.gov (United States)

    1985-06-13

    MATHPAL and 3. RAI.- Ground electrostatic field changes due to lightning 89 1 XII 2B-3 Y. GOTO, K. NARITA, M. NAITO and R. FUNAYAMA.- Electric...t 8 3H2 M.W. Maier et al. Tabla 3. - DIrictlon flndar bearing arror (in dagraaa] for tin triggered flaahsa. I Direction Flndar Flaah 1 Flaah

  12. Electrically floating, near vertical incidence, skywave antenna

    Science.gov (United States)

    Anderson, Allen A.; Kaser, Timothy G.; Tremblay, Paul A.; Mays, Belva L.

    2014-07-08

    An Electrically Floating, Near Vertical Incidence, Skywave (NVIS) Antenna comprising an antenna element, a floating ground element, and a grounding element. At least part of said floating ground element is positioned between said antenna element and said grounding element. The antenna is separated from the floating ground element and the grounding element by one or more electrical insulators. The floating ground element is separated from said antenna and said grounding element by one or more electrical insulators.

  13. Interatomic potentials, electric properties, and spectroscopy of the ground and excited states of the Rb_2 molecule: Ab initio calculations and effect of a non-resonant field

    CERN Document Server

    Tomza, Michał; Musiał, Monika; González-Férez, Rosario; Koch, Christiane P; Moszynski, Robert

    2013-01-01

    In this paper we formulate the theory of the interaction of a diatomic linear molecule in a spatially degenerate state with the non-resonant laser field and of the rovibrational dynamics in the presence of the field. We report on \\textit{ab initio} calculations employing the double electron attachment intermediate Hamiltonian Fock space coupled cluster method restricted to single and double excitations for all electronic states of the Rb$_2$ molecule up to $5s+5d$ dissociation limit of about 26.000$\\,$cm$^{-1}$. In order to correctly predict the spectroscopic behavior of Rb$_2$, we have also calculated the electric transition dipole moments, non-adiabatic coupling and spin-orbit coupling matrix elements, and static dipole polarizabilities, using the multireference configuration interaction method. When a molecule is exposed to a strong non-resonant light, its rovibrational levels get hybridized. We study the spectroscopic signatures of this effect for transitions between the X$^1\\Sigma_g^+$ electronic ground ...

  14. Imaging tropical peatlands in Indonesia using ground penetrating radar (GPR and electrical resistivity imaging (ERI: implications for carbon stock estimates and peat soil characterization

    Directory of Open Access Journals (Sweden)

    X. Comas

    2015-01-01

    Full Text Available Current estimates of carbon (C storage in peatland systems worldwide indicate tropical peatlands comprise about 15% of the global peat carbon pool. Such estimates are uncertain due to data gaps regarding organic peat soil thickness and C content. Indonesian peatlands are considered the largest pool of tropical peat carbon (C, accounting for an estimated 65% of all tropical peat while being the largest source of carbon dioxide emissions from degrading peat worldwide, posing a major concern regarding long-term sources of greenhouse gases to the atmosphere. We combined a set of indirect geophysical methods (ground penetrating radar, GPR, and electrical resistivity imaging, ERI with direct observations from core samples (including C analysis to better understand peatland thickness in West Kalimantan (Indonesia and determine how geophysical imaging may enhance traditional coring methods for estimating C storage in peatland systems. Peatland thicknesses estimated from GPR and ERI and confirmed by coring indicated variation by less than 3% even for small peat-mineral soil interface gradients (i.e. below 0.02°. The geophysical data also provide information on peat matrix attributes such as thickness of organomineral horizons between peat and underlying substrate, the presence of wood layers, buttressed trees and soil type. These attributes could further constrain quantification of C content and aid responsible peatland management in Indonesia.

  15. Imaging tropical peatlands in Indonesia using ground penetrating radar (GPR) and electrical resistivity imaging (ERI): implications for carbon stock estimates and peat soil characterization

    Science.gov (United States)

    Comas, X.; Terry, N.; Slater, L.; Warren, M.; Kolka, R.; Kristijono, A.; Sudiana, N.; Nurjaman, D.; Darusman, T.

    2015-01-01

    Current estimates of carbon (C) storage in peatland systems worldwide indicate tropical peatlands comprise about 15% of the global peat carbon pool. Such estimates are uncertain due to data gaps regarding organic peat soil thickness and C content. Indonesian peatlands are considered the largest pool of tropical peat carbon (C), accounting for an estimated 65% of all tropical peat while being the largest source of carbon dioxide emissions from degrading peat worldwide, posing a major concern regarding long-term sources of greenhouse gases to the atmosphere. We combined a set of indirect geophysical methods (ground penetrating radar, GPR, and electrical resistivity imaging, ERI) with direct observations from core samples (including C analysis) to better understand peatland thickness in West Kalimantan (Indonesia) and determine how geophysical imaging may enhance traditional coring methods for estimating C storage in peatland systems. Peatland thicknesses estimated from GPR and ERI and confirmed by coring indicated variation by less than 3% even for small peat-mineral soil interface gradients (i.e. below 0.02°). The geophysical data also provide information on peat matrix attributes such as thickness of organomineral horizons between peat and underlying substrate, the presence of wood layers, buttressed trees and soil type. These attributes could further constrain quantification of C content and aid responsible peatland management in Indonesia.

  16. Field experiment for blasting crater

    Institute of Scientific and Technical Information of China (English)

    YE Tu-qiang

    2008-01-01

    A series of single hole blasting crater experiments and a variable distance multi-hole simultaneous blasting experiment was carded in the Yunfu Troilite Mine, according to the Livingston blasting crater theory. We introduce in detail, our methodology of data collection and processing from our experiments. Based on the burying depth of the explosives, the blasting crater volume was fitted by the method of least squares and the characteristic curve of the blasting crater was obtained using the MATLAB software. From this third degree polynomial, we have derived the optimal burying depth, the critical burying depth and the optimal explosive specific charge of the blasting crater.

  17. 24 CFR 3280.809 - Grounding.

    Science.gov (United States)

    2010-04-01

    ... connected to the grounding bus in the distribution panelboard or disconnecting means. (2) In the electrical... DEVELOPMENT MANUFACTURED HOME CONSTRUCTION AND SAFETY STANDARDS Electrical Systems § 3280.809 Grounding. (a) General. Grounding of both electrical and nonelectrical metal parts in a manufactured home shall...

  18. Prediction of environmental impacts of quarry blasting operation using fuzzy logic.

    Science.gov (United States)

    Fişne, Abdullah; Kuzu, Cengiz; Hüdaverdi, Türker

    2011-03-01

    Blast-induced ground vibration is one of the most important environmental impacts of blasting operations because it may cause severe damage to structures and plants in nearby environment. Estimation of ground vibration levels induced by blasting has vital importance for restricting the environmental effects of blasting operations. Several predictor equations have been proposed by various researchers to predict ground vibration prior to blasting, but these are site specific and not generally applicable beyond the specific conditions. In this study, an attempt has been made to predict the peak particle velocity (PPV) with the help of fuzzy logic approach using parameters of distance from blast face to vibration monitoring point and charge weight per delay. The PPV and charge weight per delay were recorded for 33 blast events at various distances and used for the validation of the proposed fuzzy model. The results of the fuzzy model were also compared with the values obtained from classical regression analysis. The root mean square error estimated for fuzzy-based model was 5.31, whereas it was 11.32 for classical regression-based model. Finally, the relationship between the measured and predicted values of PPV showed that the correlation coefficient for fuzzy model (0.96) is higher than that for regression model (0.82).

  19. Frequency-Dependent Attenuation of Blasting Vibration Waves

    Science.gov (United States)

    Zhou, Junru; Lu, Wenbo; Yan, Peng; Chen, Ming; Wang, Gaohui

    2016-10-01

    The dominant frequency, in addition to the peak particle velocity, is a critical factor for assessing adverse effects of the blasting vibration on surrounding structures; however, it has not been fully considered in blasting design. Therefore, the dominant frequency-dependent attenuation mechanism of blast-induced vibration is investigated in the present research. Starting with blasting vibration induced by a spherical charge propagating in an infinite viscoelastic medium, a modified expression of the vibration amplitude spectrum was derived to reveal the frequency dependency of attenuation. Then, ground vibration induced by more complex and more commonly used cylindrical charge that propagates in a semi-infinite viscoelastic medium was analyzed by numerical simulation. Results demonstrate that the absorptive property of the medium results in the frequency attenuation versus distance, whereas a rapid drop or fluctuation occurs during the attenuation of ground vibration. Fluctuation usually appears at moderate to far field, and the dominant frequency generally decreases to half the original value when rapid drop occurs. The decay rate discrepancy between different frequency components and the multimodal structure of vibration spectrum lead to the unsmooth frequency-dependent attenuation. The above research is verified by two field experiments. Furthermore, according to frequency-based vibration standards, frequency drop and fluctuation should be considered when evaluating blast safety. An optimized piecewise assessment is proposed for more accurate evaluation: With the frequency drop point as the breakpoint, the assessment is divided into two independent sections along the propagating path.

  20. ESF BLAST DESIGN ANALYSIS

    Energy Technology Data Exchange (ETDEWEB)

    E.F. fitch

    1995-03-13

    The purpose and objective of this design analysis are to develop controls considered necessary and sufficient to implement the requirements for the controlled drilling and blasting excavation of operations support alcoves and test support alcoves in the Exploratory Studies Facility (ESF). The conclusions reached in this analysis will flow down into a construction specification ensuring controlled drilling and blasting excavation will be performed within the bounds established here.

  1. Blast Overpressure Studies.

    Science.gov (United States)

    1998-05-01

    USAARL Contract Report No. CR-98-Ö3 Blast Overpressure Studies By Daniel L. Johnson EG&G Management Systems, Inc. Albuquerque, New Mexico May...Both studies were done at the Blast Overpressure-Kirtland Test Site (BOP-KTS) in New Mexico . Under a contract conducted for the USAMRMC, EG&G was... TDH -4 9 elements mounted in a David Clark 9AN/2 ear muff for added noise isolation. The calibration of the earphones was accomplished using a Bruel

  2. Electrical Resistivity Tomography and Ground Penetrating Radar for locating buried petrified wood sites: a case study in the natural monument of the Petrified Forest of Evros, Greece

    Science.gov (United States)

    Vargemezis, George; Diamanti, Nectaria; Tsourlos, Panagiotis; Fikos, Ilias

    2014-05-01

    A geophysical survey was carried out in the Petrified Forest of Evros, the northernmost regional unit of Greece. This collection of petrified wood has an age of approximately 35 million years and it is the oldest in Greece (i.e., older than the well-known Petrified Forest of Lesvos island located in the North Aegean Sea and which is possibly the largest of the petrified forests worldwide). Protection, development and maintenance projects still need to be carried out at the area despite all fears regarding the forest's fate since many petrified logs remain exposed both in weather conditions - leading to erosion - and to the public. This survey was conducted as part of a more extensive framework regarding the development and protection of this natural monument. Geophysical surveying has been chosen as a non-destructive investigation method since the area of application is both a natural ecosystem and part of cultural heritage. Along with electrical resistivity tomography (ERT), ground penetrating radar (GPR) surveys have been carried out for investigating possible locations of buried fossilized tree trunks. The geoelectrical sections derived from ERT data in combination with the GPR profiles provided a broad view of the subsurface. Two and three dimensional subsurface geophysical images of the surveyed area have been constructed, pointing out probable locations of petrified logs. Regarding ERT, petrified trunks have been detected as high resistive bodies, while lower resistivity values were more related to the surrounding geological materials. GPR surveying has also indicated buried petrified log locations. As these two geophysical methods are affected in different ways by the subsurface conditions, the combined use of both techniques enhanced our ability to produce more reliable interpretations of the subsurface. After the completion of the geophysical investigations of this first stage, petrified trunks were revealed after a subsequent excavation at indicated

  3. Remote operated vehicle with carbon dioxide blasting (ROVCO{sub 2})

    Energy Technology Data Exchange (ETDEWEB)

    Resnick, A.M. [Oceaneering International, Inc., Upper Marlboro, MD (United States)

    1995-10-01

    The Remote Operated Vehicle with Carbon Dioxide Blasting (ROVCO{sub 2}), as shown in a front view is a six-wheeled remote land vehicle used to decontaminate concrete floors. The remote vehicle has a high pressure Cryogenesis blasting subsystem, Oceaneering Technologies (OTECH) developed a CO{sub 2} xY Orthogonal Translational End Effector (COYOTEE) subsystem, and a vacuum/filtration and containment subsystem. The cryogenesis subsystem performs the actual decontamination work and consists of the dry ice supply unit, the blasting nozzle, the remotely controlled electric and pneumatic valves, and the vacuum work-head. The COYOTEE subsystem positions the blasting work-head within a planar work space and the vacuum subsystem provides filtration and containment of the debris generated by the CO{sub 2} blasting. It employs a High Efficiency Particulate Air (HEPA) filtration unit to separate contaminants for disposal. All of the above systems are attached to the vehicle subsystem via the support structure.

  4. The field enhancement factor of sand-blasted electrodes

    DEFF Research Database (Denmark)

    McAllister, Iain Wilson; Vibholm (fratrådt), Svend

    1992-01-01

    A sample of six sand-blasted electrodes has been subjected to both mechanical and electrical investigations. When the surfaces of a series of conductors are mechanically treated, the resultant microscopic surface geometries will be similar, but not identical. As a consequence of this spread in th...... enhancement factor m for a particular surface treatment. For the sample studied, the mean electric field enhancement factor was found to be 6.6. The mechanical surface parameters indicated a sand aging effect...

  5. High-low-blasting technology and its application in methane dynamic disaster prevention

    Institute of Scientific and Technical Information of China (English)

    LI Xian-zhong; LIN Bai-quan; YANG Wei; NI Guan-hua; LI Quan-gui

    2011-01-01

    The gas cooperative control model combined local pressure-relief with regional pressure-relief was established,based on the theory of multi-parameters cooperative.For the status of high gas contents,high in-situ stress and low-permeability of Ji-15 seam of No.12 coal mine in Pingmei Group.The law of detonation wave propagation and ground-stress change distribution were simulated by means of the finite element analysis software.The technology of high-low-blasting,composed of high blasting(deep crossing hole controlled hydraulic blasting) and low blasting (special roadway deep hole controlled blasting) were developed.The research shows that around control hole produce maximum tension fracture failure,and result in directional and controlled blasting,when the distance between control hole and blasting hole is 1.2 m.The theory makes blasting force and hydraulic force advantage superimpose,which raises the effect of pressure relief and permeability enhancements compared with general blasting.High blasting influence radius and low blasting influence radius superimposed with each other,that prevents methane dynamic disaster.The result of type approval test shows that the technology can increase gas permeability as high as 22.7~36.2 ratio,decrease gas pressure from 2.85 MPa to 0.30 MPa,increase drilling influence radius to about 9 m.The technology realizes regional overall permeability improvement,that provides a new technical measure for methane dynamic disaster prevention.

  6. Simulation Analysis on Power Frequency Electric Field at Ground Surface Near EHV Power Transmission Tower%超高压输电线路铁塔附近地面工频电场仿真分析

    Institute of Scientific and Technical Information of China (English)

    李永明; 范与舟; 徐禄文

    2013-01-01

    根据铁塔实际结构和导线抛物线方程,建立了铁塔附近三维电场计算模型.基于模拟电荷法分析了500 kV输电线路铁塔周围地面上的工频电场分布,分析了铁塔对其附近电场环境的影响,并讨论了影响电场计算结果的因素.研究结果表明:铁塔对其附近地面电场有一定屏蔽作用,电场强度在铁塔下方显著降低且在金属构架处产生畸变;铁塔的影响范围和铁塔高度及塔基尺寸有关;铁塔构架等效半径、线单元剖分段数以及铁塔不同简化模型都会影响计算结果.%Based on actual structure of power transmission tower and parabolic equation of transmission lines,a three-dimensional model to compute power frequency electric field at ground surface near transmission tower is built.According to charge simulation method,the distribution of power frequency electric field at ground surface near 500kV transmission tower as well as the impacts of transmission tower on nearby electric field is analyzed,and the factors impacting computational results of electric field are discussed.Research results show that there is a certain screening effect of transmission tower on ground surface electric field nearby the tower,so the electric field intensity beneath the tower decreases obviously and electric field distortion appears at the positions where metal frameworks are erected.The impacting area is related to the height of the tower and the size of tower foundation; computational result of electric field will be impacted by the equivalent radius of tower framework,the number of line segments and different simplified models of the tower.

  7. Analysis of MINIE2013 Explosion Air-Blast Data

    Energy Technology Data Exchange (ETDEWEB)

    Schnurr, Julie M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Univ. of Hawaii, Manoa, HI (United States); Rodgers, Arthur J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kim, Keehoon [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ford, Sean R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ramirez, Abelardo L. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2016-10-14

    We report analysis of air-blast overpressure measurements from the MINIE2013 explosive experiments. The MINIE2013 experiment involved a series of nearly 70 near-surface (height-ofburst, HOB, ranging from -1 to +4 m) low-yield (W=2-20 kg TNT equivalent) chemical highexplosives tests that were recorded at local distances (230 m – 28.5 km). Many of the W and HOB combinations were repeated, allowing for quantification of the variability in air-blast features and corresponding yield estimates. We measured canonical signal features (peak overpressure, impulse per unit area, and positive pulse duration) from the air-blast data and compared these to existing air-blast models. Peak overpressure measurements showed good agreement with the models at close ranges but tended to attenuate more rapidly at longer range (~ 1 km), which is likely caused by upward refraction of acoustic waves due to a negative vertical gradient of sound speed. We estimated yields of the MINIE2013 explosions using the Integrated Yield Determination Tool (IYDT). Errors of the estimated yields were on average within 30% of the reported yields, and there were no significant differences in the accuracy of the IYDT predictions grouped by yield. IYDT estimates tend to be lower than ground truth yields, possibly because of reduced overpressure amplitudes by upward refraction. Finally, we report preliminary results on a development of a new parameterized air-blast waveform.

  8. CONTROL OF FRAGMENTATION BY BLASTING

    Directory of Open Access Journals (Sweden)

    Branko Božić

    1998-12-01

    Full Text Available The degree of fragmentation influences the economy of the excavation operations. Characteristics of blasted rock such as fragment size, volume and mass are fundamental variables effecting the economics of a mining operation and are in effect the basis for evaluating the quality of a blast. The properties of fragmentation, such as size and shape, are very important information for the optimization of production. Three factors control the fragment size distribution: the rock structure, the quantity of explosive and its distribution within the rock mass. Over the last decade there have been considerable advances in our ability to measure and analyze blasting performance. These can now be combined with the continuing growth in computing power to develop a more effective description of rock fragmentation for use by future blasting practitioners. The paper describes a view of the fragmentation problem by blasting and the need for a new generation of engineering tools to guide the design and implementation of blasting operations.

  9. 'Development and introduction of ice water conveyance system and verification of low temperature blast system' for leveling off electric power load; Denryoku fuka heijunka wo misueta 'hyosui hanso hoshiki no kaihatsu donyu to teion sofu hoshiki no kensho'

    Energy Technology Data Exchange (ETDEWEB)

    Kuriyama, T. [Nikken Sekkei Ltd., Osaka (Japan)

    1999-11-05

    From the view point of the earth environment protection, energy-saving in the field of building air-conditioning has become increasingly important. On the other hand, the utilization of nighttime electric power is needed to ease the electric power supply and demand problem, and in this connection, a wider introduction of the ice heat storage system is recommended as one of the means to cope with such a problem. However, the ice heat storage system also has problems to be solved such as energy savability, and economy. Under such circumstances, various technical research and development efforts as well as evaluation thereof have been made centering around the 'technical development of the ice water conveyance system' and the 'evaluation of the low temperature blast system' for energy-saving, facility cost reduction and electric power load leveling off, and as a matter of fact these systems have been installed in actual buildings with useful results. (author)

  10. An Assessment of Blasting Vibrations: A Case Study on Quarry Operation

    Directory of Open Access Journals (Sweden)

    Alessandro Giraudi

    2009-01-01

    Full Text Available Problem statement: One of the major environmental concerns related to blasting operation in mining and civil engineering projects is ground vibration. Approach: This study presented an assessment of ground vibrations caused by the blasting experiments at a marlstone quarry in northern Italy. The primary goal of this study was to determine the vibration level in order to protect dwelling area adjacent to the quarry. Based on the data obtained from the field, a new equation for the level of ground vibrations was proposed. Results: A comparative analysis between the results obtained by the new equation and common empirical predictors currently used in blasting practice was also carried out. Conclusion: Results indicated that a new equation may be used as a reliable predictor of the vibration level for the studied quarry.

  11. Blast effects of external explosions

    OpenAIRE

    Sochet, Isabelle

    2010-01-01

    International audience; Security considerations for industrial production and storage require characterization of the mechanical effects caused by blast waves resulting from a detonation or deflagration. This paper evaluates current analytical methods to determine the characteristic parameters of a blast wave with respect to the pressure, impulse and duration of the positive phase of the blast. In the case of a detonation, the trinitrotoluene (TNT) equivalent-based method determines the mass ...

  12. The lost church of Montemurro (Basilicata, Italy): Ground Penetrating Radar and Electrical Resistivity Tomography for detecting its buried remains in S. Maria Square.

    Science.gov (United States)

    Bavusi, Massimo; Giocoli, Alessandro; de Martino, Gregory; Loperte, Antonio; Lapenna, Vincenzo

    2010-05-01

    Montemurro is a little centre town located in the Agri Valley (Basilicata Region, Italy) which was affected by two catastrophic events: in the 1842 a very large landslide has damaged great part of the centre and in the 1857 the town was destroyed completely by the "Great Neapolitan Earthquake" (Mallet, 1862), a seismic event having epicenter in the Agri Valley (Cello et al., 2003; Bavusi et al., 2004). Signs of those tragic events can be still found in the fabric of the city. One of these is certainly S. Maria square, a place suspected to house a church before the disastrous events of 1842. This suspicion is supported by a series of evidences: a historical drawing, dating back to before 1842, shows a church in position compatible with the location of the square; in aerial view S. Maria square appears as tear in the fabric of the city; the tales of the erderlies of Montemurro speak about an ancient missing church in the town. Then, in the attempt to resolve the doubt about the presence of the church, a geophysical survey was planned in S. Maria Square with the aim to detect some buried masonry structures related to the church. In this work we selected two active techniques such as the Ground Penetrating Radar (GPR) and the Electrical Resistivity Tomography (ERT). Sixty parallel GPR profiles 0.5 m spaced were gathered in S. Maria Square and in a contiguous street by using a GSSI SIR3000 system with a central frequency antenna of 200 MHz. Processed radargrams showed numerous reflectors and heterogeneities in the subsoil related to manmade objects. Then, a laborious data processing (Nuzzo et al., 2002) allowed to obtain several time-slices showing noticeable reflections compatible with masonry structures. Moreover, two ERT profiles were carried out by using an IRIS Syscal R2 system equipped with a multielectrode cable. The first ERT profile 86 m long and having 44 electrodes 2 m spaced allowed to investigate up to 9 m of depth. The second, overlapped on the previous

  13. Rock blasting and explosives engineering

    Energy Technology Data Exchange (ETDEWEB)

    Persson, P.-A.; Holmberg, R.; Lee, J. (New Mexico Institute of Mining and Technology, Socorro, NM (United States). Research Center for Energetic Materials)

    1994-01-01

    The book covers the practical engineering aspects of different kinds of rock blasting. It includes a thorough analysis of the cost of the entire process of tunneling by drilling and blasting compared with full-face boring. It covers the economics of the entire rock blasting operation and its dependence on the size of excavation. The book highlights the fundamentals of rock mechanics, shock waves and detonation, initiation and mechanics of rock motion. It describes the engineering design principles and computational techniques for many separate mining methods and rock blasting operations. 274 refs.

  14. International Aerospace and Ground Conference on Lightning and Static Electricity (8th), Lightning Technology Roundup. Held in Fort Worth, Texas on 21-23 June 1983. Addendum

    Science.gov (United States)

    1983-10-01

    velocity, angle of attack and dis- "Electrical Measurement of Pulverized ŕ tance downstream. The core of the vortex Coal Suspension ," J. Engr. for...electric field and particle "Measurement Of Electro-Static Charge density distributions downstream of the On Solid Gas Suspension Flow," Rev...radial distance greater than the visible damage Comportement a la Foudre de Structures en .’- reported in reference (7). Materiaux Composites Haut Module

  15. Numerical Simulation of Dynamic Response and Collapse for Steel Frame Structures Subjected to Blast Load

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiuhua; DUAN Zhongdong; ZHANG Chunwei

    2008-01-01

    The progressive collapse of steel frame structures under the blast load was investigated using LS-DYNA.The multi-material Eulerian and Lagrangian coupling algorithm was adopted.A fluid-structure coupling finite element model was established which consists of Lagrange element for simulating steel frame structures and concrete ground,multiple ALE element for simulating air and TNT explosive material.Numerical simulations of the blast pressure wave propagation,structural dynamic responses and deformation,and progressive collapse of a five-story steel frame structure in the event of an explosion near above ground were performed.The numerical analysis showed that the Lagrangian and Eulerian coupling algorithm gave good simulations of the shock wave propagation in the mediums and blast load effects on the structure.The columns subjected to blast load may collapse by shear yielding rather than by flexural deformation.The columns and joints of steel beam to column in the front steel frame structure generated enormous plastic deformation subjected to intensive blast waves,and columns lost carrying capacity,subsequently leading to the collapse of the whole structure.The approach coupling influence between structural deformation and fluid load well simulated the progressive collapse process of structures,and provided an effective tool for analyzing the collapse mechanism of the steel frame structure under blast load.

  16. Valorization of electric arc furnace primary steelmaking slags for cement applications.

    Science.gov (United States)

    Kim, Hyung-Seok; Kim, Kee-Seok; Jung, Sung Suk; Hwang, Jin Ill; Choi, Jae-Seok; Sohn, Il

    2015-07-01

    To produce supplementary cementitious materials from electric arc furnace (EAF) slags, FeO was reduced using a two-stage reduction process that included an Al-dross reduction reaction followed by direct carbon reduction. A decrease in FeO was observed on tapping after the first-stage reduction, and further reduction with a stirred carbon rod in the second-stage reduction resulted in final FeO content below 5wt%, which is compatible with cement clinker applications. The reduced electric arc furnace slags (REAFS) mixed with cement at a unit ratio exhibited physical properties comparable to those of commercialized ground granulated blast furnace slags (GGBFS). Confocal laser scanning microscopy (CLSM) was used to obtain fundamental information on the cooling characteristics and conditions required to obtain amorphous REAFS. REAFS can be applied in cement mixtures to achieve the hydraulic properties needed for commercial use. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. 30 CFR 18.24 - Electrical clearances.

    Science.gov (United States)

    2010-07-01

    ... Requirements § 18.24 Electrical clearances. Minimum clearances between uninsulated electrical conductor surfaces, or between uninsulated conductor surfaces and grounded metal surfaces, within the enclosure...

  18. 29 CFR 1926.912 - Underwater blasting.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Underwater blasting. 1926.912 Section 1926.912 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Blasting and the Use of Explosives § 1926.912 Underwater blasting. (a) A blaster shall conduct all blasting operations, and no shot shall be fired...

  19. 30 CFR 57.6803 - Blasting lines.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Blasting lines. 57.6803 Section 57.6803 Mineral... and Underground § 57.6803 Blasting lines. Permanent blasting lines shall be properly supported. All blasting lines shall be insulated and kept in good repair. General Requirements—Surface and Underground...

  20. 30 CFR 56.6803 - Blasting lines.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Blasting lines. 56.6803 Section 56.6803 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Blasting lines. Permanent blasting lines shall be properly supported. All blasting lines shall be...

  1. Identification of blast resistance genes for managing rice blast disease

    Science.gov (United States)

    Rice blast, caused by the fungal pathogen Magnaporthe oryzae, is one of the most devastating diseases worldwide. In the present study, an international set of monogenic differentials carrying 24 major blast resistance (R) genes (Pia, Pib, Pii, Pik, Pik-h, Pik-m, Pik-p, Pik-s, Pish, Pit, Pita, Pita2,...

  2. Manual for the prediction of blast and fragment loadings on structures

    Energy Technology Data Exchange (ETDEWEB)

    1980-11-01

    The purpose of this manual is to provide Architect-Engineer (AE) firms guidance for the prediction of air blast, ground shock and fragment loadings on structures as a result of accidental explosions in or near these structures. Information in this manual is the result of an extensive literature survey and data gathering effort, supplemented by some original analytical studies on various aspects of blast phenomena. Many prediction equations and graphs are presented, accompanied by numerous example problems illustrating their use. The manual is complementary to existing structural design manuals and is intended to reflect the current state-of-the-art in prediction of blast and fragment loads for accidental explosions of high explosives at the Pantex Plant. In some instances, particularly for explosions within blast-resistant structures of complex geometry, rational estimation of these loads is beyond the current state-of-the-art.

  3. Shock tubes and blast injury modeling

    Institute of Scientific and Technical Information of China (English)

    Ya-Lei Ning; Yuan-Guo Zhou

    2015-01-01

    Explosive blast injury has become the most prevalent injury in recent military conflicts and terrorist attacks.The magnitude of this kind of polytrauma is complex due to the basic physics of blast and the surrounding environments.Therefore,development of stable,reproducible and controllable animal model using an ideal blast simulation device is the key of blast injury research.The present review addresses the modeling of blast injury and applications of shock tubes.

  4. NCBI BLAST: a better web interface.

    Science.gov (United States)

    Johnson, Mark; Zaretskaya, Irena; Raytselis, Yan; Merezhuk, Yuri; McGinnis, Scott; Madden, Thomas L

    2008-07-01

    Basic Local Alignment Search Tool (BLAST) is a sequence similarity search program. The public interface of BLAST, http://www.ncbi.nlm.nih.gov/blast, at the NCBI website has recently been reengineered to improve usability and performance. Key new features include simplified search forms, improved navigation, a list of recent BLAST results, saved search strategies and a documentation directory. Here, we describe the BLAST web application's new features, explain design decisions and outline plans for future improvement.

  5. Numerical simulation of muzzle blast

    NARCIS (Netherlands)

    Tyler-Street, M.

    2014-01-01

    Structural design methods for naval ships include environmental, operational and military load cases. One of the operational loads acting on a typical naval vessel is the muzzle blast from a gun. Simulating the muzzle blast load acting on a ship structure with CFD and ALE methods leads to large nume

  6. BLAST: the Redshift Survey

    CERN Document Server

    Eales, Stephen; Devlin, Mark J; Dye, Simon; Halpern, Mark; Hughes, David H; Marsden, Gaelen; Mauskopf, Philip; Moncelsi, Lorenzo; Netterfield, Calvin B; Pascale, Enzo; Patanchon, Guillaume; Raymond, Gwenifer; Rex, Marie; Scott, Douglas; Semisch, Christopher; Siana, Brian; Truch, Matthew D P; Viero, Marco P

    2009-01-01

    The Balloon-borne Large Aperture Submillimeter Telescope (BLAST) has recently surveyed ~=8.7 deg^2 centered on GOODS-South at 250, 350 and 500 microns. In Dye et al. (2009) we presented the catalogue of sources detected at $\\rm 5\\sigma$ in at least one band in this field and the probable counterparts to these sources in other wavebands. In this paper, we present the results of a redshift survey in which we succeeded in measuring redshifts for 83 of these counterparts. We have used the spectroscopic redshifts to carry out a test of the ability of photometric redshift methods to estimate the redshifts of dusty galaxies. We have also investigated the cases where there are two possible counterparts to the BLAST source, finding that in at least half of these there is evidence that the two galaxies are physically associated, either because they are interacting or because they are in the same large-scale structure. Finally, we have made the first direct measurements of the luminosity function in the three BLAST band...

  7. Demystifying blast effects on buildings

    Energy Technology Data Exchange (ETDEWEB)

    Malhotra, A.; Carson, D.; Stevens, T. [Halsall Associates Ltd., Toronto, ON (Canada)

    2007-07-01

    This paper presented methods of designing the structures of building structures in such a way that the effects of blast loads can be mitigated. The methods were designed to provide strength and ductility so that kinetic energy delivered by the blast is resisted by strain energy. Fundamental aspects of blast effects were examined, and the design of flexural members subject to blast loading were discussed. An equivalent static load procedure based on the equivalency of kinetic and strain energies was also presented along with a threat independent approach which included principles to prevent progressive collapse, ductile columns, and the addition of upward resistance to floors. Measures to mitigate damage caused by shattered glass and other cladding elements during blasts were also discussed.

  8. Circulation in blast driven instabilities

    Science.gov (United States)

    Henry de Frahan, Marc; Johnsen, Eric

    2016-11-01

    Mixing in many natural phenomena (e.g. supernova collapse) and engineering applications (e.g. inertial confinement fusion) is often initiated through hydrodynamic instabilities. Explosions in these systems give rise to blast waves which can interact with perturbations at interfaces between different fluids. Blast waves are formed by a shock followed by a rarefaction. This wave profile leads to complex time histories of interface acceleration. In addition to the instabilities induced by the acceleration field, the rarefaction from the blast wave decompresses the material at the interface, further increasing the perturbation growth. After the passage of the wave, circulation circulation generated by the blast wave through baroclinic vorticity continues to act upon the interface. In this talk, we provide scaling laws for the circulation and amplitude growth induced by the blast wave. Numerical simulations of the multifluid Euler equations solved using a high-order accurate Discontinuous Galerkin method are used to validate the theoretical results.

  9. 46 CFR 120.376 - Grounded distribution systems (Neutral grounded).

    Science.gov (United States)

    2010-10-01

    ... ELECTRICAL INSTALLATION Power Sources and Distribution Systems § 120.376 Grounded distribution systems... distribution system having a neutral bus or conductor must have the neutral grounded. (c) The neutral or each... generator is connected to the bus, except the neutral of an emergency power generation system must...

  10. Design of Surge Protection & Ground Connection at Four Electricity Integration Field in Railway Section%铁路区间四电综合场坪防雷接地系统集约化设计实践

    Institute of Scientific and Technical Information of China (English)

    林明嘉

    2014-01-01

    On the basis of the previous substation design and the study of the national and industrial standards and railway technique specifications for surge protection and grounding design, and with reference to Ha - Da passenger dedicated line, surge protection & ground connection design of Four Electricity ( Communication, Signal, Power and Electrification) Integration field in railway section is discussed and practiced to solve the problems encountered in this regard. This paper puts forward new ideas with respect to some particulars and requirements, which may be used as references in future design of surge protection & ground connection.%在参考以往变电站接地设计的基础上,通过对国家和行业标准以及铁路技术规章有关防雷接地要求的研究,以哈大客运专线为例,对铁路区间四电场坪各系统设备进行统一的综合接地设计进行探讨和实践,试图解决类似设计中所面临的主要难点,并在某些细节的做法和要求提出了自己的看法,希望能对以后的设计有所借鉴。

  11. The Use of Rice Varietal Diversity for Rice Blast Control

    Institute of Scientific and Technical Information of China (English)

    ZHU You-yong; LI Zuo-shen; LU Bao-rong; CHEN Hai-ru; FAN Jing-hua; WANG Yun-yue; LI Yan; FAN Jin-xiang; YANG Shi-sheng; MA Guan-liang; CHEN Jian-bin

    2003-01-01

    Field experiments of mixed- (intercropping) and pure-planting (monoculture) of four rice vari-eties, representing improved hybrid varieties (Shanyou63 and Shanyou22) and high-quality traditional varie-ties (Huangkenuo and Zigu) from Yunnan Province, were conducted based on their differences in genetic back-ground and agro-economical characteristics. The results demonstrated that the mixed-planting of the hybridrice and high-quality traditional rice varieties had a significantly greater effect on controlling rice blast diseasethan the monocuiture of these varieties, particularly the traditional ones. It is evident for the highly suscepti-ble traditional varieties in mixed-planting to achieve disease control, with significant decreases in blast inci-dences and severity indexes. The blast control efficiency reached up to 83 - 98 % under such planting model.This suggests that an appropriate mixed-planting of rice varieties with diverse genetic background and agro-e-conomical characteristics is an effective approach for rice blast control. In addition, resistance of the tradi-tional rice varieties to lodging was considerably increased in the plots with mixed-planting, compared with theplots with monoculture. The average rate of grain-yield increase ranged from 6.5 to 9.7 % in the plots withmixed-planting.

  12. Reliability and Assessment Techniques on Ground Excavation

    Directory of Open Access Journals (Sweden)

    Sanga Tangchawal

    2009-05-01

    Full Text Available Planning and assessment on the excavation of the brittle materials (soil or rock can be done by using the machinery and/or explosives. The reliability assessment has been proposed to predict the failure of ground during excavation process. The stability planning on cutting soil (rock face by machinery can be compared between the deterministic and the statistical method. The risk of using explosives for rock excavation has to concern on the damage and environmental impacts after blasting events.

  13. Application of vertical electrical sounding combined with induced polarization method in ground water exploration; IP koka wo koryoshita hiteikoho suichoku tansa no chikasui chosa eno tekiyo

    Energy Technology Data Exchange (ETDEWEB)

    Kondo, M.; Sakurada, H. [Sumiko Consultants Co. Ltd., Tokyo (Japan); Suzuki, T. [Hokkaido Development Bureau, Hokkaido Development Agency, Sapporo (Japan)

    1996-10-01

    For ground water exploration using vertical Schlumberger exploration method, measurement and analysis combined with induced polarization (IP) effect were conducted as trial. For the Schlumberger method, potential is measured at the center between potential electrodes during flow of dc current between current electrodes. In the case of vertical exploration, measurements are repeated with fixed potential electrodes by extending the distance between current electrodes. Ground water exploration was conducted using this method at Otaki village, Hokkaido. Geology of surveyed plateau consists of a basement of Pliocene tuffs and Quaternary Pleistocene sediments covering on the surface. For the results of analysis, four to seven beds were detected from the resistivity. The depth up to the lowest bed was between 25 and 85 m, the resistivity of each bed was between 9 and 8,000 ohm{times}m, and the polarizability was between 1 and 15 mV/V. Among these resistivity zones, it was judged that zones satisfying following three conditions correspond to coarse grain sediments saturated with ground water, and can be expected as aquifers; having resistivity ranging between 100 and 1,000 ohm{times}m, polarizability higher than 10 mV/V, and relatively large thickness. 11 refs., 6 figs.

  14. Sorption and desorption of iron-cyanide complexes in deposited blast furnace sludge.

    Science.gov (United States)

    Rennert, Thilo; Mansfeldt, Tim

    2002-11-01

    Blast furnace sludge is a waste originating from pig iron production and contains small amounts of iron-cyanide complexes. Leaching of iron-cyanide complexes from deposited blast furnace sludge into the ground water seems to be possible in principle. We investigated the sorption of the iron-cyanide complexes ferrocyanide, [FeII(CN)6](4-), and ferricyanide, [FeIII(CN)6](3-), in 22 samples of deposited blast furnace sludge in batch experiments. Subsequently, desorption of iron-cyanide complexes was investigated using 1 M NaCl. Sorption in five samples was evaluated with Langmuir isotherms. The blast furnace sludge samples were neutral to slightly alkaline (pH 7.6-9) and consisted of X-ray amorphous compounds and crystalline Fe oxides primarily. X-ray amorphous compounds are assumed to comprise coke-bound C and amorphous Fe, Zn, and Al oxides. The experiments that were evaluated with Langmuir isotherms indicated that the extent of ferricyanide sorption was higher than that of ferrocyanide sorption. Saturation of blast furnace sludge with iron-cyanide complexes was achieved. Sorption of iron-cyanide complexes in 22 blast furnace sludge samples at one initial concentration showed that 12 samples sorbed more ferrocyanide than ferricyanide. The extent of sorption largely differed between 0.07 and 2.76 Micromol [Fe(CN)6] m(-2) and was governed by coke-bound C. Ferricyanide sorption was negatively influenced by crystalline Fe oxides additionally. Only small amounts of iron-cyanide complexes sorbed in blast furnace sludge were desorbed by 1 M NaCl (ferrocyanide, 3.2%; ferricyanide, 1.1%, given as median). This indicated strong interactions of iron-cyanide complexes in blast furnace sludge. The mobility of iron-cyanide complexes in deposited blast furnace sludge and consequently contamination of the seepage and ground water was designated as low, because (i) deposited blast furnace sludge is able to sorb iron-cyanide complexes strongly, (ii) the solubility of the iron

  15. International Aerospace and Ground Conference on Lightning and Static Electricity (15th) Held in Atlantic City, New Jersey on October 6 - 8, 1992. Addendum

    Science.gov (United States)

    1992-11-01

    Current Channel to a Uniaxially Anisotropic Composite Skin . 62-1 Poh H. Ng, Paul M. McKenna Study of Atmospheric Electrical Events Above Complex Terrain...Lightning by Launch V ehicles .................. ............................... ... 74-1" Rodney A. Perala, Terence H. Rudolph, Calvin C. Easterbrook...MacGorman, Donald R. 55* Rudolph, Terence H. 74 Maier, Matthew R. 28 Matsuura, K. 60, 61 Sanicandro, Rocco 7t Mauriello, A. J. 34 Sargent, Noel B. 36

  16. Grounded theory.

    Science.gov (United States)

    Harris, Tina

    2015-04-29

    Grounded theory is a popular research approach in health care and the social sciences. This article provides a description of grounded theory methodology and its key components, using examples from published studies to demonstrate practical application. It aims to demystify grounded theory for novice nurse researchers, by explaining what it is, when to use it, why they would want to use it and how to use it. It should enable nurse researchers to decide if grounded theory is an appropriate approach for their research, and to determine the quality of any grounded theory research they read.

  17. A Study on Nuclear Blast Overpressure on Buildings and other infrastructures using Geospatial Technology

    Directory of Open Access Journals (Sweden)

    D. Thirumalaivasan

    2012-01-01

    Full Text Available An Improvised Nuclear Device or nuclear bomb of yield 10 kiloton to 20 kiloton explodes in any major city due to terrorism or any other reason can cause catastrophic damages on the building's and other infrastructures and also shutting down of critical life-safety systems.. The explosion may produce blast overpressure, thermal radiation and harmful instant and delayed nuclear radiations. The buildings and other Civil Engineering structures may be highly vulnerabke due to the blast overpressure from the explosion and thermal radiation. In this present study Remote Sensing and Geographical Information System is effectively utilized to model the blast affected zone from the ground Zero of the study area. This study also introduces different emperical methods to estimate blast loads and structural response. The purpose is to describe the blast effects of a nuclear explosion, thereby informing people of the real dangers posed by nuclear weapons. Therefore, as a case study, we consider a hypothetical City as a target for detonation. Due to security reasons the data for existing City is not used for this study purpose. The study area is hypothetically detonated with a 15 kiloton yield nuclear explosion as surface blast and wind spped is assumed as 5 meters per second.

  18. 接地开关电动操动机构的研发与结构设计研究%Grounding Switch Electric Operating Mechanism Research and Structure Design Research

    Institute of Scientific and Technical Information of China (English)

    李小平

    2014-01-01

    With the development of the electric power industry, the high voltage switch equipment also got great development. Parts of the high voltage switch disconnected or grounding switch in the closing switch points, used for gear transmission structure or screw the two transmission ways. The two transmission ways to switch design put forward higher request, only the design more perfect switch electric operating mechanism, to provide support for the drive way. In addition, the modern distribution system and power system is becoming more and more high to the requirement of switchgear, so, must accelerate the earthing switch electric operation, promote the earthing switch in many aspects, such as monitoring, control and protection of intelligent, improve the accuracy of the grounding switch electric operating mechanism and reliability.%随着电力事业的发展,高压开关设备也得到了很大的发展。高压开关中的部分隔离开关或接地开关在进行开关分合闸时,使用了传动结构为齿轮或丝杆的两种传动方式。这两种传动方式对开关设计提出了更高的要求,只有设计出更完善的开关电动操动机构,才能为这种传动方式提供支撑。此外,现代配电系统和用电系统对开关设备的要求也越来越高,所以,必须要加速接地开关的电动操作,促进接地开关在监测、控制和保护等诸多方面的智能化,提高接地开关电动操作机构的准确性和可靠程度。

  19. 75 FR 56489 - Separation Distances of Ammonium Nitrate and Blasting Agents From Explosives or Blasting Agents...

    Science.gov (United States)

    2010-09-16

    ... Ammonium Nitrate and Blasting Agents From Explosives or Blasting Agents (2002R-226P) AGENCY: Bureau of... CFR 555.220 set forth a table of separation distances of ammonium nitrate and blasting agents from explosives or blasting agents followed by six explanatory notes. Note three (3) states that the...

  20. Power Tillers for Demining: Blast Test

    Directory of Open Access Journals (Sweden)

    Emanuela Elisa Cepolina

    2008-11-01

    Full Text Available Power tillers are very simple and versatile machines with large scale diffusion in developing countries, where they are commonly used both for agriculture and for transportation purposes. A new integrated participatory approach that makes use of and improves local end-users knowledge has been used to design a new robotic system for humanitarian demining applications in Sri Lanka, using power tiller as core module. A demining machine composed by a tractor unit, a ground processing tool and a vegetation cutting tool is here presented together with results obtained from the first blast test on the preliminary version of tractor unit armouring. Different breakable connections between wheels and axle have been designed to cause physical detachment and interrupt the transmission of the shock wave released by the explosion of a mine under one wheel. Effects of explosions on different types of wheels and on the chassis have been recorded and commented.

  1. Experimental Study on the Measurement of Water Bottom Vibration Induced by Underwater Drilling Blasting

    Directory of Open Access Journals (Sweden)

    Gu Wenbin

    2015-01-01

    Full Text Available Due to the lack of proper instrumentations and the difficulties in underwater measurements, the studies about water bottom vibration induced by underwater drilling blasting are seldom reported. In order to investigate the propagation and attenuation laws of blasting induced water bottom vibration, a water bottom vibration monitor was developed with consideration of the difficulties in underwater measurements. By means of this equipment, the actual water bottom vibration induced by underwater drilling blasting was measured in a field experiment. It shows that the water bottom vibration monitor could collect vibration signals quite effectively in underwater environments. The followed signal analysis shows that the characteristics of water bottom vibration and land ground vibration induced by the same underwater drilling blasting are quite different due to the different geological environments. The amplitude and frequency band of water bottom vibration both exceed those of land ground vibration. Water bottom vibration is mainly in low-frequency band that induced by blasting impact directly acts on rock. Besides the low-frequency component, land vibration contains another higher frequency band component that induced by followed water hammer wave acts on bank slope.

  2. 小电流接地电网故障选线方法的研究%Research on Low Current Grounding Electric Network Fault Line Selection

    Institute of Scientific and Technical Information of China (English)

    何金朋; 聂赫; 刘颖

    2011-01-01

    The 35 kV or below power distribution network in China and small current grounding system single phase occurs single grounding,there is less difference between normal lines and fault line transient zero sequence current,which affects the precision of line selection.In view of this,one kind of digital filter is designed.The pure fault component of zero sequence current is extracted and the data is being analyzed,combined with substation automation generatrix insulate monitoring device and automation reclose device,the fault line is selected.The theoretical analysis and Matlab simulation experiment indicates the accuracy and reliability of line selection method has improved significantly.%针对我国35 kV及以下配电网小电流接地系统发生单相接地时,健全线路与故障线路暂态零序电流相差不大,影响了选线的精度等状况,设计了一种数字滤波器。它可提取零序电流的纯故障分量,对数据进行相关分析,结合变电站自动化母线绝缘监视装置以及自动重合闸装置,选出故障线路。通过理论分析和Matlab实验仿真表明,这种选线方法,其准确性、可靠性有明显提高。

  3. Reliability of Hydrox explosive blasting

    Energy Technology Data Exchange (ETDEWEB)

    Chikunov, V.I.; Chulkov, O.G.; Domanov, V.P.

    1980-03-01

    The safest method of blasting in coal mines with methane and coal dust hazards is with the flameless Hydrox charges. The results of operational tests on Hydrox BV-A2U charges with a I-43 initiator in underground coal mines are discussed. Efficiency and reliability of blasting using Hydrox BV-A2U compared to BV-48 Hydrox charges is evaluated. Results of blasting and the percentage of charge failures are given in tables. It is suggested that BV-A2U Hydrox charges are superior to BV-48, as no charge failures occur, operational time of BV-A2U is up to 5 seconds and the maximum operational time spread is 1.8 sec (weight of initiator 0.05 kg). Blasting properties of BV-A2U are stable and do not change as a result of long storage. (In Russian)

  4. Source model for blasting vibration

    Institute of Scientific and Technical Information of China (English)

    DING; Hua(丁桦); ZHENG; Zhemin(郑哲敏)

    2002-01-01

    By analyzing and comparing the experimental data, the point source moment theory and the cavity theory, it is concluded that the vibrating signals away from the blasting explosive come mainly from the natural vibrations of the geological structures near the broken blasting area. The source impulses are not spread mainly by the inelastic properties (such as through media damping, as believed to be the case by many researchers) of the medium in the propagation pass, but by this structure. Then an equivalent source model for the blasting vibrations of a fragmenting blasting is proposed, which shows the important role of the impulse of the source's time function under certain conditions. For the purpose of numerical simulation, the model is realized in FEM, The finite element results are in good agreement with the experimental data.

  5. Explosive Blast Neuropathology and Seizures

    Directory of Open Access Journals (Sweden)

    S. Krisztian eKovacs

    2014-04-01

    Full Text Available Traumatic brain injury (TBI due to explosive blast exposure is a leading combat casualty. It is also implicated as a key contributor to war related mental health diseases. A clinically important consequence of all types of TBI is a high risk for development of seizures and epilepsy. Seizures have been reported in patients who have suffered blast injuries in the Global War on Terror but the exact prevalence is unknown. The occurrence of seizures supports the contention that explosive blast leads to both cellular and structural brain pathology. Unfortunately, the exact mechanism by which explosions cause brain injury is unclear, which complicates development of meaningful therapies and mitigation strategies. To help improve understanding, detailed neuropathological analysis is needed. For this, histopathological techniques are extremely valuable and indispensable. In the following we will review the pathological results, including those from immunohistochemical and special staining approaches, from recent preclinical explosive blast studies.

  6. Centrifugal shot blast system

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-02-01

    This report describes a demonstration of Concrete cleaning, Inc., modified centrifugal shot blast technology to remove the paint coating from concrete flooring. This demonstration is part of the Chicago Pile-5 (CP-5) Large-Scale Demonstration Project (LSDP) sponsored by the US Department of Energy (DOE), office of Science and Technology (OST), Deactivation and Decommissioning Focus Area (DDFA). The objective of the LSDP is to select and demonstrate potentially beneficial technologies at the Argonne National Laboratory-East (ANL) CP-5 Research Reactor. The purpose of the LSDP is to demonstrate that using innovative and improved decontamination and decommissioning (D and D) technologies from various sources can result in significant benefits, such as decreased cost and increased health and safety, as compared with baseline D and D technologies. Potential markets exist for the innovative centrifugal shot blast system at the following sites: Fernald Environmental Management Project, Los Alamos, Nevada, Oak Ridge Y-12 and K-25, Paducah, Portsmouth Gaseous Diffusion site, and the Savannah River Site. This information is based on a revision to the OST Linkage Tables dated August 4, 1997.

  7. Grounded cognition.

    Science.gov (United States)

    Barsalou, Lawrence W

    2008-01-01

    Grounded cognition rejects traditional views that cognition is computation on amodal symbols in a modular system, independent of the brain's modal systems for perception, action, and introspection. Instead, grounded cognition proposes that modal simulations, bodily states, and situated action underlie cognition. Accumulating behavioral and neural evidence supporting this view is reviewed from research on perception, memory, knowledge, language, thought, social cognition, and development. Theories of grounded cognition are also reviewed, as are origins of the area and common misperceptions of it. Theoretical, empirical, and methodological issues are raised whose future treatment is likely to affect the growth and impact of grounded cognition.

  8. Design of Blast Resistant Structure

    Directory of Open Access Journals (Sweden)

    C. K. Gautam

    1997-04-01

    Full Text Available A shock blast resistant structure designed, developed and experimentally evaluated by the authors is described. We structure, capable of with standing dynamic loading (12 psi and a static pressure of 1.5 m earth cover due to blast or any other explosion, also gives protection against radiation, chemical and thermal hazards. Some results and details of analysis and experimentation are presented.

  9. Porcine head response to blast

    Directory of Open Access Journals (Sweden)

    Jay eShridharani

    2012-05-01

    Full Text Available Recent studies have shown an increase in the frequency of traumatic brain injuries related to blast exposure. However, the mechanisms that cause blast neurotrauma are unknown. Blast neurotrauma research using computational models has been one method to elucidate that response of the brain in blast, and to identify possible mechanical correlates of injury. However, model validation against experimental data is required to ensure that the model output is representative of in vivo biomechanical response. This study exposed porcine subjects to primary blast overpressures generated using a compressed-gas shock tube. Shock tube blasts were directed to the unprotected head of each animal while the lungs and thorax were protected using ballistic protective vests similar to those employed in theater. The test conditions ranged from 110-740 kPa peak incident overpressure with scaled durations from 1.3-6.9 ms and correspond approximately with a 50% injury risk for brain bleeding and apnea in a ferret model scaled to porcine exposure. The bulk head acceleration and the pressure at the surface of the head and in the cranial cavity were measured. Immediately after the blast, 5 of the 20 animals tested were apneic. Three subjects recovered without intervention within thirty seconds and the remaining two recovered within 8 minutes following bagging and administration of the respiratory stimulant doxapram. Gross examination of the brain revealed no indication of bleeding. Intracranial pressures ranged from 80-685 kPa as a result of the blast and were notably lower than the shock tube reflected pressures of 300-2830 kPa, indicating pressure attenuation by the skull up to a factor of 8.4. Peak head accelerations were measured from 385-3845 G’s and were well correlated with peak incident overpressure (R2=0.90. One standard deviation corridors for the surface pressure, intracranial pressure, and head acceleration are presented to provide experimental data for

  10. FEATURES OF DRILLING-AND-BLASTING AT CONSTRUCTION OF BESKIDSKIY TUNNEL

    Directory of Open Access Journals (Sweden)

    V. D. Petrenko

    2016-10-01

    blowing using mine fans of special mining enterprises. Originality. The developed seismically safety charge masses are based on the well-known state about antiseismic blasting regulations. Practical value. The authors proposed and grounded the efficient technology for reduction to practice of drilling and blasting works (with dividing of the tunnel cross-section into the calotte and stross during of the Beskydy high-mountain tunnel construction. The results of technological experiment are presented.

  11. Rock fragmentation control in opencast blasting

    Directory of Open Access Journals (Sweden)

    P.K. Singh

    2016-04-01

    Full Text Available The blasting operation plays a pivotal role in the overall economics of opencast mines. The blasting sub-system affects all the other associated sub-systems, i.e. loading, transport, crushing and milling operations. Fragmentation control through effective blast design and its effect on productivity are the challenging tasks for practicing blasting engineer due to inadequate knowledge of actual explosive energy released in the borehole, varying initiation practice in blast design and its effect on explosive energy release characteristic. This paper describes the result of a systematic study on the impact of blast design parameters on rock fragmentation at three mines in India. The mines use draglines and shovel–dumper combination for removal of overburden. Despite its pivotal role in controlling the overall economics of a mining operation, the expected blasting performance is often judged almost exclusively on the basis of poorly defined parameters such as powder factor and is often qualitative which results in very subjective assessment of blasting performance. Such an approach is very poor substitutes for accurate assessment of explosive and blasting performance. Ninety one blasts were conducted with varying blast designs and charging patterns, and their impacts on the rock fragmentation were documented. A high-speed camera was deployed to record the detonation sequences of the blasts. The efficiency of the loading machines was also correlated with the mean fragment size obtained from the fragmentation analyses.

  12. BLEVE blast by expansion-controlled evaporation

    NARCIS (Netherlands)

    Berg, A.C. van den; Voort, M.M. van der; Weerheijm, J.; Versloot, N.H.A.

    2006-01-01

    This report presents a new method to calculate the blast effects originating from an exploding vessel of liquefied gas. Adequate blast calculation requires full knowledge of the blast source characteristics, that is, the release and subsequent evaporation rate of the flashing liquid. Because the

  13. 30 CFR 72.610 - Abrasive blasting.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Abrasive blasting. 72.610 Section 72.610... HEALTH STANDARDS FOR COAL MINES Miscellaneous § 72.610 Abrasive blasting. (a) Surface and underground mines. When an abrasive blasting operation is performed, all exposed miners shall properly...

  14. BLEVE blast by expansion-controlled evaporation

    NARCIS (Netherlands)

    Berg, A.C. van den; Voort, M.M. van der; Weerheijm, J.; Versloot, N.H.A.

    2006-01-01

    This report presents a new method to calculate the blast effects originating from an exploding vessel of liquefied gas. Adequate blast calculation requires full knowledge of the blast source characteristics, that is, the release and subsequent evaporation rate of the flashing liquid. Because the con

  15. 30 CFR 58.610 - Abrasive blasting.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Abrasive blasting. 58.610 Section 58.610... SAFETY AND HEALTH HEALTH STANDARDS FOR METAL AND NONMETAL MINES Miscellaneous § 58.610 Abrasive blasting. (a) Surface and underground mines. When an abrasive blasting operation is performed, all...

  16. Long-term Geophysical Monitoring of Simulated Clandestine Graves using Electrical and Ground Penetrating Radar Methods: 4-6 Years After Burial.

    Science.gov (United States)

    Pringle, Jamie K; Jervis, John R; Roberts, Daniel; Dick, Henry C; Wisniewski, Kristopher D; Cassidy, Nigel J; Cassella, John P

    2016-03-01

    This ongoing monitoring study provides forensic search teams with systematic geophysical data over simulated clandestine graves for comparison to active cases. Simulated "wrapped," "naked," and "control" burials were created. Multiple geophysical surveys were collected over 6 years, here showing data from 4 to 6 years after burial. Electrical resistivity (twin electrode and ERI), multifrequency GPR, grave and background soil water were collected. Resistivity surveys revealed that the naked burial had low-resistivity anomalies up to year four but then difficult to image, whereas the wrapped burial had consistent large high-resistivity anomalies. GPR 110- to 900-MHz frequency surveys showed that the wrapped burial could be detected throughout, but the naked burial was either not detectable or poorly resolved. 225-MHz frequency GPR data were optimal. Soil water analyses showed decreasing (years 4 to 5) to background (year 6) conductivity values. Results suggest both resistivity and GPR surveying if burial style unknown, with winter to spring surveys optimal and increasingly important as time increases.

  17. DYNAMIC INFLUENCE CAUSED BY CLOSE BLASTING ON PRIMARY AND SECONDARY SUPPORT SYSTEM IN TUNNEL "SV. ROK"

    Directory of Open Access Journals (Sweden)

    Zvonimir Ester

    2003-12-01

    Full Text Available At the construction site of the road tunnel Sv. Rok, the second, left tunnels tube is being constructed parallel to the unfinished right tunnel. The part of right tunnel tube is supported with primary support system according to NAMT, the second part is supported complete with concrete. Distance between axes of the tunnel tubes is approximately 35 m. Drifting of the left tube is being done by blasting. A potential problem of damaging the surrounding rock and support system was recognized. It is well known that the ground vibration particle velocity due to a blast is a measure of damage on the nearby construction. The three component seismographs were used to measure ground oscillation velocities in the right tunnel tube. Total of 30 measurements were executed and 720 values were processed (including all three component oscillation velocities. Maximum ground oscillation velocity recorded was 232.061 mm/s. This paper brings conclusion derived from monitoring data achieved at close proximity to the blasting area, damage level criteria for the rock mass and support system and discusses how these results could assist further development in the control of blasting technique.

  18. 30 CFR 77.1300 - Explosives and blasting.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Explosives and blasting. 77.1300 Section 77... Explosives and Blasting § 77.1300 Explosives and blasting. (a) No explosives, blasting agent, detonator, or any other related blasting device or material shall be stored, transported, carried, handled,...

  19. 30 CFR 75.1326 - Examination after blasting.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Examination after blasting. 75.1326 Section 75... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1326 Examination after blasting. (a) After blasting, the blasting area shall not be entered until it is clear of...

  20. Numerical simulation of stress for the blasting of foundation pit

    Institute of Scientific and Technical Information of China (English)

    FEI Hong-lu; ZHAO Xin-pu

    2008-01-01

    Through the simulation of explicit dynamic analysis software LS-DYNA, made an analysis to the particle velocity and the stress distribution of surrounding rock when the explosives blasting. Explicated the mechanical character of surrounding rock in the foun-dation pit blasting, provided a basis to set of blasting parameters and optimized the blast-ing construction.

  1. 30 CFR 780.13 - Operation plan: Blasting.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Operation plan: Blasting. 780.13 Section 780.13... Operation plan: Blasting. (a) Blasting plan. Each application shall contain a blasting plan for the proposed... methods to be applied in controlling the adverse effects of blasting operations. (b) Monitoring...

  2. Ground ice conditions in Salluit, Northern Quebec

    Science.gov (United States)

    Allard, M.; Fortier, R.; Calmels, F.; Gagnon, O.; L'Hérault, E.

    2011-12-01

    Salluit in Northern Québec (ca. 1300 inhabitants) faces difficult ground ice conditions for its development. The village is located in a U-shaped valley, along a fjord that was deglaciated around 8000 cal BP. The post-glacial marine limit is at the current elevation of 150 m ASL. Among the mapped surficial geology units, three contain particularly ice-rich permafrost: marine clays, till and silty colluviums. A diamond drill was used to extract 10 permafrost cores down to 23 m deep. In addition, 18 shallow cores (to 5 m deep) were extracted with a portable drill. All the frozen cores were shipped to Québec city where ground ice contents were measured and cryostructures were imaged by CT-Scanning. Water contents, grain-size and pore water salinity were measured. Refraction seismic profiles were run to measure the depth to bedrock. GPR and electrical resistivity surveys helped to map ice-rich areas. Three cone penetration tests (CPT) were run in the frozen clays to depths ranging from 8 to 21 m. Maximum clay thickness is ca. 50 m deep near the shoreline. The cone penetration tests and all the cores in clays revealed large amounts of both segregated and aggradational ice (volumetric contents up to 93% over thicknesses of one meter) to depths varying between 2.5 and 4 m, below which the ice content decreases and the salinity increases (values measured up to 42 gr/L between 4.5 and 6 m deep). Chunks of organic matter buried below the actual active layer base indicate past cryoturbations under a somewhat warmer climate, most probably associated with intense frost boil action, as widely observed today. The stony till has developed large quantities of segregation ice which can be seen in larger concentrations and as thicker lenses under boulders and in matrix rich (≥ 50% sand and silt) parts of the glacial sediment. As digging for a sewage pond was undertaken in winter 2008 by blasting, the clast-influenced cryostructure of the till could be observed in cuts and in

  3. Toxicology of blast overpressure.

    Science.gov (United States)

    Elsayed, N M

    1997-07-25

    Blast overpressure (BOP) or high energy impulse noise, is the sharp instantaneous rise in ambient atmospheric pressure resulting from explosive detonation or firing of weapons. Blasts that were once confined to military and to a lesser extent, occupational settings, are becoming more universal as the civilian population is now increasingly at risk of exposure to BOP from terrorist bombings that are occurring worldwide with greater frequency. Exposure to incident BOP waves can cause auditory and non-auditory damage. The primary targets for BOP damage are the hollow organs, ear, lung and gastrointestinal tract. In addition, solid organs such as heart, spleen and brain can also be injured upon exposure. However, the lung is more sensitive to damage and its injury can lead to death. The pathophysiological responses, and mortality have been extensively studied, but little attention, was given to the biochemical manifestations, and molecular mechanism(s) of injury. The injury from BOP has been, generally, attributed to its external physical impact on the body causing internal mechanical damage. However, a new hypothesis has been proposed based on experiments conducted in the Department of Respiratory Research, Walter Reed Army Institute of Research, and later in the Department of Occupational Health, University of Pittsburgh. This hypothesis suggests that subtle biochemical changes namely, free radical-mediated oxidative stress occur and contribute to BOP-induced injury. Understanding the etiology of these changes may shed new light on the molecular mechanism(s) of injury, and can potentially offer new strategies for treatment. In this symposium. BOP research involving auditory, non-auditory, physiological, pathological, behavioral, and biochemical manifestations as well as predictive modeling and current treatment modalities of BOP-induced injury are discussed.

  4. Photovoltaic module mounting clip with integral grounding

    Science.gov (United States)

    Lenox, Carl J.

    2010-08-24

    An electrically conductive mounting/grounding clip, usable with a photovoltaic (PV) assembly of the type having an electrically conductive frame, comprises an electrically conductive body. The body has a central portion and first and second spaced-apart arms extending from the central portion. Each arm has first and second outer portions with frame surface-disrupting element at the outer portions.

  5. 27 CFR 555.220 - Table of separation distances of ammonium nitrate and blasting agents from explosives or blasting...

    Science.gov (United States)

    2010-04-01

    ... distances of ammonium nitrate and blasting agents from explosives or blasting agents. 555.220 Section 555... ammonium nitrate and blasting agents from explosives or blasting agents. Table: Department of Defense... Blasting agent Minimum thickness of artificial barricades (in.) 100 3 11 12 100 300 4 14 12 300 600 5 18...

  6. Ground Wars

    DEFF Research Database (Denmark)

    Nielsen, Rasmus Kleis

    Political campaigns today are won or lost in the so-called ground war--the strategic deployment of teams of staffers, volunteers, and paid part-timers who work the phones and canvass block by block, house by house, voter by voter. Ground Wars provides an in-depth ethnographic portrait of two...... infrastructures that utilize large databases with detailed individual-level information for targeting voters, and armies of dedicated volunteers and paid part-timers. Nielsen challenges the notion that political communication in America must be tightly scripted, controlled, and conducted by a select coterie...... of professionals. Yet he also quashes the romantic idea that canvassing is a purer form of grassroots politics. In today's political ground wars, Nielsen demonstrates, even the most ordinary-seeming volunteer knocking at your door is backed up by high-tech targeting technologies and party expertise. Ground Wars...

  7. Simulating geometrically complex blast scenarios

    Directory of Open Access Journals (Sweden)

    Ian G. Cullis

    2016-04-01

    Full Text Available The effects of blast waves generated by energetic and non-energetic sources are of continuing interest to the ballistics research community. Modern conflicts are increasingly characterised by asymmetric urban warfare, with improvised explosive devices (IEDs often playing a dominant role on the one hand and an armed forces requirement for minimal collateral effects from their weapons on the other. These problems are characterised by disparate length- and time-scales and may also be governed by complex physics. There is thus an increasing need to be able to rapidly assess and accurately predict the effects of energetic blast in topologically complex scenarios. To this end, this paper presents a new QinetiQ-developed advanced computational package called EAGLE-Blast, which is capable of accurately resolving the generation, propagation and interaction of blast waves around geometrically complex shapes such as vehicles and buildings. After a brief description of the numerical methodology, various blast scenario simulations are described and the results compared with experimental data to demonstrate the validation of the scheme and its ability to describe these complex scenarios accurately and efficiently. The paper concludes with a brief discussion on the use of the code in supporting the development of algorithms for fast running engineering models.

  8. Simulating geometrically complex blast scenarios

    Institute of Scientific and Technical Information of China (English)

    Ian G. CULLIS; Nikos NIKIFORAKIS; Peter FRANKL; Philip BLAKELY; Paul BENNETT; Paul GREENWOOD

    2016-01-01

    The effects of blast waves generated by energetic and non-energetic sources are of continuing interest to the ballistics research community. Modern conflicts are increasingly characterised by asymmetric urban warfare, with improvised explosive devices (IEDs) often playing a dominant role on the one hand and an armed forces requirement for minimal collateral effects from their weapons on the other. These problems are characterised by disparate length-and time-scales and may also be governed by complex physics. There is thus an increasing need to be able to rapidly assess and accurately predict the effects of energetic blast in topologically complex scenarios. To this end, this paper presents a new QinetiQ-developed advanced computational package called EAGLE-Blast, which is capable of accurately resolving the generation, propagation and interaction of blast waves around geometrically complex shapes such as vehicles and buildings. After a brief description of the numerical methodology, various blast scenario simulations are described and the results compared with experimental data to demonstrate the validation of the scheme and its ability to describe these complex scenarios accurately and efficiently. The paper concludes with a brief discussion on the use of the code in supporting the development of algorithms for fast running engineering models.

  9. 电动汽车车身平顺性及车轮接地性分析与优化%Analysis and Optimization of Ride Comfort and Wheel Ground Adhesion of Electric Vehicle

    Institute of Scientific and Technical Information of China (English)

    张擎宇; 陈辛波

    2014-01-01

    以某分布式四轮驱动电动汽车为研究对象,在Adams/car中建立了整车模型,通过对前、后悬架参数进行灵敏度分析,探讨其对车身平顺性与车轮接地性的影响。基于α法建立评价车身平顺性与车轮接地性指标的多目标函数,对灵敏度较高的悬架参数进行优化设计。结果表明,优化后前、后悬架的刚度减小,前悬架的阻尼增大。与优化前相比,车身垂向加速度均方根值减小16%,左、右前轮动载荷的均方根值均减小11%。%With a distributed 4WD electric vehicle as research object, a vehicle model is constructed in Adams/car environment. Sensitivity analysis is made to the front and rear suspension parameters, its effect on ride comfort and wheel ground adhesion is investigated. Multi-objective function to evaluate body ride comfort and wheel ground adhesion is established based on α method and suspension parameters with high sensitivity are optimized. The results indicate that stiffness of the optimized front and rear suspension descends, whereas damping of the front suspension ascends. Compared with the suspension before optimization, the root-mean-square value of body vertical acceleration is reduced by 16%, and that of the front wheels on both sides is reduced by 11%.

  10. Blast Loading on above Ground Barricaded Munition Storage Magazines.

    Science.gov (United States)

    1984-05-01

    2073 227 0.490 0.49 p2. * . -- .4’ -ID fi1~~< .*. di * ~22 -o, ..i w7I-.7-, .* , . -. -. • . ’... .7 7 9 .. . TEST: QUICKLOAD AMMO 309 SHOT: 3 488...S5 5%5. * .-....-. ’.... -%...- - -.- .- - TEST: QUICKLOAD AMMO 3r SHOT. 3 480 256STATION: 3 1 - 388 ~ISM 296 * V) . 8 0.5 t 1.5 2 TID, HSEC TEST...STATION: 2 los - a 8.5 I 1.5 2 TII( MSEC TEST: QUICKLOAD AMMO 3880 SHOT: 4 2 480 3STATION- 2 388 28W lo wO oo " . 9 _5_ 8 8 .51 . TME, MSEC TEST

  11. Blast Loading on Above Ground Barricaded Munition Storage Magazines - II

    Science.gov (United States)

    1986-08-01

    BARRICADES Peak Arrival Shot Station Distance Overpressure Impulse Time Duration Remarks m kPa kPa-ms ms ms 19 1.006 1537 207 0.48 1.16 0.8Q / 3m 20 1.523 279...STATI(ON: 14 2m - 2-W 1. I. 2 S9.5 Il 1.52 "TEST": STORAG AFT 3 _ SWOT : 2 .200 258Peo 15F20: ISO • Station 14 1709 TEST: $TW SAFETY i m I - ISO...3.79 2.42 1711 TEST- STORAGE SAFETY SwOT : I Ise IW T40, IC TEST.: STORAG AFl I SliOT2 Is. Ise 19 IW 5.5 6 .5 1 1.5 2 TIME, C TEST: STORAGE SAFETY a0s

  12. Performance monitoring of electric shovels digging oil sands

    Energy Technology Data Exchange (ETDEWEB)

    Patnayak, S. [Alberta Univ., Edmonton, AB (Canada). Natural Resources Engineering Facility; Tannant, D.D. [Alberta Univ., Edmonton, AB (Canada). School of Mining and Petroleum Engineering; Parsons, I. [Syncrude Canada Ltd., Edmonton, AB (Canada). Edmonton Research Centre; Del Valle, V. [Syncrude Canada Ltd., Fort McMurray, AB (Canada)

    2005-07-01

    Some of the largest available mining equipment is used for oil sand mining operations. However, the performance of electric cable shovels varies with the diggability characteristics of the ground. In particular, oil sands diggability with cable shovels depends on structural geology, the depositional environment and geotechnical parameters. This paper described some of the key shovel performance indicators such as dig cycle time, digging energy and digging power. In winter, frost penetration can also affect oil sands diggability. The challenge of hard digging in oil sands is often addressed by blasting or ripping, which increases the cost of production and impedes productivity. The shovel performance is also influenced by other parameters such as operator skills, bucket and tooth design and shovel dipper trajectory. This paper demonstrated that hoist and crowd motor voltages and currents are useful in identifying the beginning and end of dig cycles. Performance indicators such as dig cycle time, hoist motor energy and power, and crowd motor energy and power were considered to assess material diggability. It was suggested that hoist power represents the ground diggability better than other performance indicators. 5 refs., 1 tab., 10 figs.

  13. 30 CFR 57.20031 - Blasting underground in hazardous areas.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Blasting underground in hazardous areas. 57... MINES Miscellaneous § 57.20031 Blasting underground in hazardous areas. In underground areas where... removed to safe places before blasting....

  14. Improved BLAST for wireless communications

    Institute of Scientific and Technical Information of China (English)

    Li Yongzhao; Liao Guisheng; Wang Feng

    2006-01-01

    Bell layered space-time architecture (BLAST) is a multi-antenna communication structure with high spectrum efficiency, and it has found wide applications in LANs and WLANs. However, its performance is much poorer than those of other space-time coding approaches. In order to improve its performance, an improved BLAST based on RAKE receiving is investigated. The new system introduces orthogonal spreading sequences (OSS) into the transmitter while retains the basic structure of BLAST. The proposed receiver suppresses interferences from other antennas by the orthogonality contained in the received signals, and extracts information from each receiving antenna by using RAKE receiving principle to construct efficient statistic decision. Simulation results show that the improved system performs well over both frequency-flat and frequency-selective fading channels.

  15. Numerical simulation of the fluid-structure interaction between air blast waves and soil structure

    Science.gov (United States)

    Umar, S.; Risby, M. S.; Albert, A. Luthfi; Norazman, M.; Ariffin, I.; Alias, Y. Muhamad

    2014-03-01

    Normally, an explosion threat on free field especially from high explosives is very dangerous due to the ground shocks generated that have high impulsive load. Nowadays, explosion threats do not only occur in the battlefield, but also in industries and urban areas. In industries such as oil and gas, explosion threats may occur on logistic transportation, maintenance, production, and distribution pipeline that are located underground to supply crude oil. Therefore, the appropriate blast resistances are a priority requirement that can be obtained through an assessment on the structural response, material strength and impact pattern of material due to ground shock. A highly impulsive load from ground shocks is a dynamic load due to its loading time which is faster than ground response time. Of late, almost all blast studies consider and analyze the ground shock in the fluid-structure interaction (FSI) because of its influence on the propagation and interaction of ground shock. Furthermore, analysis in the FSI integrates action of ground shock and reaction of ground on calculations of velocity, pressure and force. Therefore, this integration of the FSI has the capability to deliver the ground shock analysis on simulation to be closer to experimental investigation results. In this study, the FSI was implemented on AUTODYN computer code by using Euler-Godunov and the arbitrary Lagrangian-Eulerian (ALE). Euler-Godunov has the capability to deliver a structural computation on a 3D analysis, while ALE delivers an arbitrary calculation that is appropriate for a FSI analysis. In addition, ALE scheme delivers fine approach on little deformation analysis with an arbitrary motion, while the Euler-Godunov scheme delivers fine approach on a large deformation analysis. An integrated scheme based on Euler-Godunov and the arbitrary Lagrangian-Eulerian allows us to analyze the blast propagation waves and structural interaction simultaneously.

  16. Blast-Induced Damage on Millisecond Blasting Model Test with Multicircle Vertical Blastholes

    Directory of Open Access Journals (Sweden)

    Qin-yong Ma

    2015-01-01

    Full Text Available To investigate the blast-induced damage effect on surrounding rock in vertical shaft excavation, 4 kinds of millisecond blasting model tests with three-circle blastholes were designed and carried out with excavation blasting in vertical shaft as the background. The longitudinal wave velocity on the side of concrete model was also measured before and after blasting. Then blast damage factor was then calculated by measuring longitudinal wave velocity before and after blasting. The test results show that the blast-induced damage factor attenuated gradually with the centre of three-circle blastholes as centre. With the threshold value of 0.19 for blast-induced damage factor, blast-induced damage zones for 4 kinds of model tests are described and there is an inverted cone blast-induced damage zone in concrete model. And analyses of cutting effect and blast-induced damage zone indicate that in order to minimize the blast-induced damage effect and ensure the cutting effect the reasonable blasting scheme for three-circle blastholes is the inner two-circle blastholes initiated simultaneously and the outer third circle blastholes initiated in a 25 ms delay.

  17. EFFECTS OF BLAST-FURNACE SLAG ON NATURAL POZZOLAN-BASED GEOPOLYMER CEMENT

    Directory of Open Access Journals (Sweden)

    MAHSHAD YAZDANIPOUR

    2011-03-01

    Full Text Available A number of geopolymer cement mixes were designed and produced by alkali-activation of a pumice-type natural pozzolan. Effects of blast-furnace slag on basic engineering properties of the mixes were studied. Different engineering properties of the mixes such as setting times and 28-day compressive strength were studied at different amounts of blast-furnace slag, sodium oxide content, and water-to-cement ratio. The mix comprising of 5 wt.% blast-furnace slag and 8 wt.% Na2O with a water-to-dry binder ratio of 0.30 exhibits the highest 28-day compressive strength, i.e. 36 MPa. Mixes containing 5 wt.% of ground granulated blast furnace slag showed the least efflorescence or best soundness. Laboratory techniques of X-ray diffractometry (XRD, fourier transform infrared spectroscopy (FTIR, and scanning electron microscopy (SEM were utilized for characterizing a number of mixes and studying their molecular and micro-structure. Investigations done by scanning electron microscopy confirm that smaller blast-furnace slag particles react totally while the larger ones react partially with alkaline activators and contribute to the formation of a composite microstructure.

  18. Blast Wave Characteristics and Equivalency

    OpenAIRE

    Sochet, Isabelle; Schneider, Helmut

    2010-01-01

    ISBN 978-5-94588-079-5; The characteristics of blast waves generated by detonation of gas clouds are studies theoretically and validated by both small-scale and large-scale experiments with ethylene-air mixtures of different equivalence ratio. The mixtures were confined in hemispherical or spherical balloons made from thin polyethylene foils of 0.75 m³ and 15 m³ in volume. The detonation of gas mixtures was initiated by a solid explosive. The characteristics of the blast wave in terms of over...

  19. Electric and magnetic dipole shielding constants for the ground state of the relativistic hydrogen-like atom: Application of the Sturmian expansion of the generalized Dirac-Coulomb Green function

    CERN Document Server

    Stefańska, Patrycja

    2011-01-01

    The Sturmian expansion of the generalized Dirac-Coulomb Green function [R. Szmytkowski, J. Phys. B 30 (1997) 825; erratum 30 (1997) 2747] is exploited to derive closed-form expressions for electric ($\\sigma_{\\mathrm{E}}$) and magnetic ($\\sigma_{\\mathrm{M}}$) dipole shielding constants for the ground state of the relativistic hydrogen-like atom with a point-like and spinless nucleus of charge $Ze$. It is found that $\\sigma_{\\mathrm{E}}=Z^{-1}$ (as it should be) and $$\\sigma_{\\mathrm{M}}=-(2Z\\alpha^{2}/27)(4\\gamma_{1}^{3}+6\\gamma_{1}^{2}-7\\gamma_{1}-12) /[\\gamma_{1}(\\gamma_{1}+1)(2\\gamma_{1}-1)],$$ where $\\gamma_{1}=\\sqrt{1-(Z\\alpha)^{2}}$ ($\\alpha$ is the fine-structure constant). This expression for $\\sigma_{\\mathrm{M}}$ agrees with earlier findings of several other authors, obtained with the use of other analytical techniques, and is elementary compared to an alternative one presented recently by Cheng \\emph{et al.} [J. Chem. Phys. 130 (2009) 144102], which involves an infinite series of ratios of the Euler'...

  20. Ground state prop erties and excitation prop erties of ZnSe under different external electric fields%ZnSe在外电场下的基态性质和激发特性研究∗

    Institute of Scientific and Technical Information of China (English)

    李世雄; 吴永刚; 令狐荣锋; 孙光宇; 张正平; 秦水介

    2015-01-01

    The Hartree-Fork (HF) method with LANL2DZ basis set is used to investigate the equilibrium structures, atomic charge distributions, the highest occupied molecular orbital (HOMO) energy levels, the lowest unoccupied molecular orbital (LUMO) energy levels, energy gaps, dipole moments, harmonic frequencies and infrared intensities of ZnSe under different external electric fields ranging from −0.025 to 0.040 a.u. The excitation energies, transition wavelengths and oscillator strengths under the same external electric fields are calculated by the time-dependent-HF method. The results show that the bond length and electric dipole moment are proved to be first decreasing, and then increasing with the variation of the external field; the total energy is found to decrease linearly with the variation of external field; but the HOMO energy and energy gap are proved to increase with the variation of external field. The harmonic frequency and LUMO energy are found to first increase, and then decrease, but the infrared intensities are proved to first decrease, and then increase. The external electric field has significant effect on the excitation properties of ZnSe molecule. The excited energies from ground state to the first nine excited states are found to increase, and the transition wavelengths are decreasing with the variation of the external field. Meanwhile, the strongest excited state becomes very weak, and the weak excited state becomes strongest by the external field. The excitation properties of ZnSe material can be changed with external electric field.%以LANL2DZ为基组,采用Hartree-Fock(HF)方法研究了不同外电场(−0.025—0.040 a.u.)对ZnSe分子的基态几何结构、电荷分布、能量、电偶极矩、最高占据轨道(HOMO)能级、最低空轨道(LUMO)能级、能隙、红外光谱特性的影响;继而采用含时的TD-HF方法研究了ZnSe分子在外电场下前9个激发态的吸收谱、激发能、振子强度等激发特性.研究

  1. Recovery Act: ArcelorMittal USA Blast Furnace Gas Flare Capture

    Energy Technology Data Exchange (ETDEWEB)

    Seaman, John

    2013-01-14

    The U.S. Department of Energy (DOE) awarded a financial assistance grant under the American Recovery and Reinvestment Act of 2009 (Recovery Act) to ArcelorMittal USA, Inc. (ArcelorMittal) for a project to construct and operate a blast furnace gas recovery boiler and supporting infrastructure at ArcelorMittal’s Indiana Harbor Steel Mill in East Chicago, Indiana. Blast furnace gas (BFG) is a by-product of blast furnaces that is generated when iron ore is reduced with coke to create metallic iron. BFG has a very low heating value, about 1/10th the heating value of natural gas. BFG is commonly used as a boiler fuel; however, before installation of the gas recovery boiler, ArcelorMittal flared 22 percent of the blast furnace gas produced at the No. 7 Blast Furnace at Indiana Harbor. The project uses the previously flared BFG to power a new high efficiency boiler which produces 350,000 pounds of steam per hour. The steam produced is used to drive existing turbines to generate electricity and for other requirements at the facility. The goals of the project included job creation and preservation, reduced energy consumption, reduced energy costs, environmental improvement, and sustainability.

  2. MEASUREMENT IN BLAST HOLE STEM AND INFLUENCE OF STEMING MATERIAL ON BLASTING QUALITY

    Directory of Open Access Journals (Sweden)

    Mario Dobrilović

    2005-12-01

    Full Text Available Paper presents results of blast hole stem materials, that were conducted to assert best stem materials for surface blasting in quarry of technical / construction stone. Blasting has been performed with equal explosives and test-minefield parameters (length of the stem, volume of the explosive charge, mine-drill depth, and angle on various sites / quarry. Results are guidelines in materials to be chosen in surface blasting of quarry works, adding to quality of mining works and reduction of costs.

  3. Finite Element Analysis of Composite Hardened Walls Subjected to Blast Loads

    Directory of Open Access Journals (Sweden)

    Girum S. Urgessa

    2009-01-01

    Full Text Available Problem statement: There is currently no standard design guideline to determine the number of composites needed to retrofit masonry walls in order to withstand a given explosion. Past design approaches were mainly based on simplified single-degree-of-freedom analysis. A finite element analysis was conducted for concrete masonry walls hardened with composites and subjected to short duration blast loads. Approach: The analysis focused on displacement time history responses which form the basis for retrofit design guidelines against blast loadings. The blast was determined from 0.5 kg equivalent TNT explosive at 1.83 m stand-off distance to simulate small mailroom bombs. Two and four layered retrofitted walls were investigated. Uncertainties in the finite model analysis of walls such as pressure distributions, effect of mid height explosive bursts versus near the ground explosive bursts and variations in modulus of elasticity of the wall were presented. Results: Uniformly distributed blast loads over the retrofitted wall height produced a small difference in peak displacement results when compared to the non-uniform pressure distribution. Ground explosive burst was shown to produce a 62.7% increase in energy and a higher peak displacement response when compared to mid-height explosive burst. Conclusion: The parametric study on the variation of modulus of elasticity of concrete masonry showed no significant effect on peak displacement affirming the use of the resistance deflection contribution of the composite in retrofit designs.

  4. A geophysical shock and air blast simulator at the National Ignition Facility

    Energy Technology Data Exchange (ETDEWEB)

    Fournier, K. B.; Brown, C. G.; May, M. J.; Compton, S.; Walton, O. R.; Shingleton, N.; Kane, J. O.; Holtmeier, G.; Loey, H.; Mirkarimi, P. B.; Dunlop, W. H. [Lawrence Livermore National Laboratory, P.O. Box 808, L-481, Livermore, California 94550 (United States); Guyton, R. L.; Huffman, E. [National Securities Technologies, Vasco Rd., Livermore, California 94551 (United States)

    2014-09-15

    The energy partitioning energy coupling experiments at the National Ignition Facility (NIF) have been designed to measure simultaneously the coupling of energy from a laser-driven target into both ground shock and air blast overpressure to nearby media. The source target for the experiment is positioned at a known height above the ground-surface simulant and is heated by four beams from the NIF. The resulting target energy density and specific energy are equal to those of a low-yield nuclear device. The ground-shock stress waves and atmospheric overpressure waveforms that result in our test system are hydrodynamically scaled analogs of full-scale seismic and air blast phenomena. This report summarizes the development of the platform, the simulations, and calculations that underpin the physics measurements that are being made, and finally the data that were measured. Agreement between the data and simulation of the order of a factor of two to three is seen for air blast quantities such as peak overpressure. Historical underground test data for seismic phenomena measured sensor displacements; we measure the stresses generated in our ground-surrogate medium. We find factors-of-a-few agreement between our measured peak stresses and predictions with modern geophysical computer codes.

  5. A geophysical shock and air blast simulator at the National Ignition Facility

    Energy Technology Data Exchange (ETDEWEB)

    Fournier, K. B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Brown, C. G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); May, M. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Compton, S. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Walton, O. R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Shingleton, N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kane, J. O. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Holtmeier, G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Loey, H. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Mirkarimi, P. B. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Dunlop, W. H. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Guyton, R. L. [National Security Technologies, Livermore, CA (United States); Huffman, E. [National Security Technologies, Livermore, CA (United States)

    2014-09-01

    The energy partitioning energy coupling experiments at the National Ignition Facility (NIF) have been designed to measure simultaneously the coupling of energy from a laser-driven target into both ground shock and air blast overpressure to nearby media. The source target for the experiment is positioned at a known height above the ground-surface simulant and is heated by four beams from the NIF. The resulting target energy density and specific energy are equal to those of a low-yield nuclear device. The ground-shock stress waves and atmospheric overpressure waveforms that result in our test system are hydrodynamically scaled analogs of full-scale seismic and air blast phenomena. This report summarizes the development of the platform, the simulations, and calculations that underpin the physics measurements that are being made, and finally the data that were measured. Agreement between the data and simulation of the order of a factor of two to three is seen for air blast quantities such as peak overpressure. Historical underground test data for seismic phenomena measured sensor displacements; we measure the stresses generated in our ground-surrogate medium. We find factors-of-a-few agreement between our measured peak stresses and predictions with modern geophysical computer codes.

  6. Blast-Induced Acceleration in a Shock Tube: Distinguishing Primary and Tertiary Blast Injury

    Science.gov (United States)

    2015-10-01

    crushing action (i.e. static pressure) which envelops the head as well as some aerodynamic drag (i.e. dynamic pressure creating blast wind). The use of...with an advanced blast simulator (ABS) yield a higher fidelity, ecologically valid simulation of blast and thereby provide critical insights into

  7. Mask materials for powder blasting

    NARCIS (Netherlands)

    Wensink, Henk; Jansen, Henri V.; Berenschot, J.W.; Elwenspoek, Miko C.

    2001-01-01

    Powder blasting, or abrasive jet machining (AJM), is a technique in which a particle jet is directed towards a target for mechanical material removal. It is a fast, cheap and accurate directional etch technique for brittle materials such as glass, silicon and ceramics. The particle jet (which expand

  8. Identifying structural damage with ground penetrating radar

    CSIR Research Space (South Africa)

    Van Schoor, Abraham M

    2008-07-01

    Full Text Available Ground penetrating radar (GPR) and electrical resistance tomography (ERT) surveys were conducted in an urban environment in an attempt to identify the cause of severe structural damage to a historically significant residential property...

  9. Plastic Media Blasting Data Gathering Study

    Science.gov (United States)

    1986-12-01

    matt, reducing the filtering surface. 25 3) Cartridge Collectors: Cartridge dust collectors consist of a number of nonwoven tubular filters placed...Engineering Command 03 SPLASTIC MEDIA BLASTING DATA GATHERING STUDY: FINAL REPORT ABSTRAC>lastic Media Blasting (PMB) is proving to be a cost effective method...facilities; needed blasting and media recovery equipment; different types of media ; and media disposal. The Economics section gives two examples of economic

  10. Alkaline carbonates in blast furnace process

    Directory of Open Access Journals (Sweden)

    P. Besta

    2014-10-01

    Full Text Available The production of iron in blast furnaces is a complex of physical, chemical and mechanical processes. The input raw materials contain not only metallic components, but also a number of negative elements. The most important negative elements include alkaline carbonates. They can significantly affect the course of the blast furnace process and thus the overall performance of the furnace. As a result of that, it is essential to accurately monitor the alkali content in the blast furnace raw materials. The article analyzes the alkali content in input and output raw materials and their impact on the blast furnace process.

  11. Transmission Lines or Poles, Electric, Electricity Transmission Lines; electran; Major above ground high voltage electrical transmission lines as shown on USGS 7.5 minute topo quads and/or as confirmed through identification of visible right of way cuts on digital orthophotgraphy., Published in 2001, 1:4800 (1in=400ft) scale, State of Rhode Island and Providence Plantations.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Transmission Lines or Poles, Electric dataset, published at 1:4800 (1in=400ft) scale, was produced all or in part from Orthoimagery information as of 2001. It...

  12. Absence of Magnetic Dipolar Phase Transition and Evolution of Low-Energy Excitations in PrNb2Al20 with Crystal Electric Field Γ3 Ground State: Evidence from 93Nb-NQR Studies

    Science.gov (United States)

    Kubo, Tetsuro; Kotegawa, Hisashi; Tou, Hideki; Higashinaka, Ryuji; Nakama, Akihiro; Aoki, Yuji; Sato, Hideyuki

    2015-07-01

    We report measurements of bulk magnetic susceptibility and 93Nb nuclear quadrupole resonance (NQR) in the Pr-based caged compound PrNb2Al20. By analyzing the magnetic susceptibility and magnetization, the crystal electric field (CEF) level scheme of PrNb2Al20 is determined to be Γ3(0 K)-Γ4(21.32 K)-Γ5(43.98 K)-Γ1(51.16 K) within the framework of the localized 4f electron picture. The 93Nb-NQR spectra exhibit neither spectral broadening nor spectral shift upon cooling down to 75 mK. The 93Nb-NQR spin-lattice relaxation rate 1/T1 at 5 K depends on the frequency and remains almost constant below 5 K. The frequency dependence of 1/T1 is attributed to the magnetic fluctuation due to the hyperfine-enhanced 141Pr nuclear moment inherent in the nonmagnetic Γ3 CEF ground state. The present NQR results provide evidence that no symmetry-breaking magnetic dipole order occurs down to 75 mK. Also, considering an invariant form of the quadrupole and octupole couplings between a 93Nb nucleus and Pr 4f electrons, Pr 4f quadrupoles and an octupole can couple with a 93Nb nuclear quadrupole moment and nuclear spin, respectively. Together with the results of bulk measurements, the present NQR results suggest that the possibility of a static quadrupole or octupole ordering can be excluded down to 100 mK. At low temperatures below 500 mK, however, the nuclear spin-echo decay rate gradually increases and the decay curve changes from Gaussian decay to Lorentzian decay, suggesting the evolution of a low-energy excitation.

  13. Blast-induced electromagnetic fields in the brain from bone piezoelectricity.

    Science.gov (United States)

    Lee, Ka Yan Karen; Nyein, Michelle K; Moore, David F; Joannopoulos, J D; Socrate, Simona; Imholt, Timothy; Radovitzky, Raul; Johnson, Steven G

    2011-01-01

    In this paper, we show that bone piezoelectricity-a phenomenon in which bone polarizes electrically in response to an applied mechanical stress and produces a short-range electric field-may be a source of intense blast-induced electric fields in the brain, with magnitudes and timescales comparable to fields with known neurological effects. We compute the induced charge density in the skull from stress data on the skull from a finite-element full-head model simulation of a typical IED-scale blast wave incident on an unhelmeted human head as well as a human head protected by a kevlar helmet, and estimate the resulting electric fields in the brain in both cases to be on the order of 10 V/m in millisecond pulses. These fields are more than 10 times stronger than the IEEE safety guidelines for controlled environments (IEEE Standards Coordinating Committee 28, 2002) and comparable in strength and timescale to fields from repetitive Transcranial Magnetic Stimulation (rTMS) that are designed to induce neurological effects (Wagner et al., 2006a). They can be easily measured by RF antennas, and may provide the means to design a diagnostic tool that records a quantitative measure of the head's exposure to blast insult.

  14. 30 CFR 75.1316 - Preparation before blasting.

    Science.gov (United States)

    2010-07-01

    ... HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1316 Preparation... using a blasting multimeter or other instrument specifically designed for such use. (3) The blasting... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Preparation before blasting. 75.1316 Section...

  15. Numerical simulation of stress for the blasting of foundation pit

    Institute of Scientific and Technical Information of China (English)

    FEI Hong-lu; ZHAO Xin-pu

    2008-01-01

    Through the simulation of explicit dynamic analysis software LS-DYNA,made an analysis to the particle velocity and the stress distribution of surrounding rock when the explosives blasting.Explicated the mechanical character of surrounding rock in the foundation pit blasting,provided a basis to set of blasting parameters and optimized the blasting construction.

  16. 30 CFR 77.1304 - Blasting agents; special provisions.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Blasting agents; special provisions. 77.1304... COAL MINES Explosives and Blasting § 77.1304 Blasting agents; special provisions. (a) Sensitized ammonium nitrate blasting agents, and the components thereof prior to mixing, shall be mixed and stored...

  17. Condition for Contur Blasting use on Openpit Mines

    OpenAIRE

    Krsmanovic, I; Dambov, Risto

    2010-01-01

    For purpose of obtaining a stable final slope in open pit mines practice, the most common approach is the contour blasting method and investigation of possible applications of various primary blasting methods for purpose of gaining the optimal techno-economical effects. This paper presents one of the contour blasting methods, drilling and blasting parameters, construction of explosive charges and method of initiation.

  18. 30 CFR 75.1320 - Multiple-shot blasting.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Multiple-shot blasting. 75.1320 Section 75.1320... MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1320 Multiple-shot blasting... periods of 1,000 milliseconds or less shall be used. (d) When blasting in anthracite mines, each...

  19. 30 CFR 56.6306 - Loading, blasting, and security.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Loading, blasting, and security. 56.6306... § 56.6306 Loading, blasting, and security. (a) When explosive materials or initiating systems are... permitted within the blast site shall be those activities directly related to the blasting operation and...

  20. 29 CFR 1926.910 - Inspection after blasting.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Inspection after blasting. 1926.910 Section 1926.910 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Blasting and the Use of Explosives § 1926.910 Inspection after blasting. (a) Immediately after the blast has been fired, the firing line shall...

  1. 'Grounded' Politics

    DEFF Research Database (Denmark)

    Schmidt, Garbi

    2012-01-01

    play within one particular neighbourhood: Nørrebro in the Danish capital, Copenhagen. The article introduces the concept of grounded politics to analyse how groups of Muslim immigrants in Nørrebro use the space, relationships and history of the neighbourhood for identity political statements....... The article further describes how national political debates over the Muslim presence in Denmark affect identity political manifestations within Nørrebro. By using Duncan Bell’s concept of mythscape (Bell, 2003), the article shows how some political actors idealize Nørrebro’s past to contest the present...

  2. Dynamic Analysis of Tunnel in Weathered Rock Subjected to Internal Blast Loading

    Science.gov (United States)

    Tiwari, Rohit; Chakraborty, Tanusree; Matsagar, Vasant

    2016-11-01

    The present study deals with three-dimensional nonlinear finite element (FE) analyses of a tunnel in rock with reinforced concrete (RC) lining subjected to internal blast loading. The analyses have been performed using the coupled Eulerian-Lagrangian analysis tool available in FE software Abaqus/Explicit. Rock and RC lining are modeled using three-dimensional Lagrangian elements. Beam elements have been used to model reinforcement in RC lining. Three different rock types with different weathering conditions have been used to understand the response of rock when subjected to blast load. The trinitrotoluene (TNT) explosive and surrounding air have been modeled using the Eulerian elements. The Drucker-Prager plasticity model with strain rate-dependent material properties has been used to simulate the stress-strain response of rock. The concrete damaged plasticity model and Johnson-Cook plasticity model have been used for the simulation of stress-strain response of concrete and steel, respectively. The explosive (TNT) has been modeled using Jones-Wilkins-Lee (JWL) equation of state. The analysis results have been studied for stresses, deformation and damage of RC lining and the surrounding rock. It is observed that damage in RC lining results in higher stress in rock. Rocks with low modulus and high weathering conditions show higher attenuation of shock wave. Higher amount of ground shock wave propagation is observed in case of less weathered rock. Ground heave is observed under blast loading for tunnel close to ground surface.

  3. Blast-Resistance Inheritance of Space-Induced Rice Lines and Their Genomic Polymorphism by Microsatellite Markers

    Institute of Scientific and Technical Information of China (English)

    XIAO Wu-ming; YANG Qi-yun; CHEN Zhi-qiang; WANG Hui; GUO Tao; LIU Yong-zhu; ZHU Xiao-yuan

    2009-01-01

    To understand the resistance inheritance basis of space-induced rice lines to blast,and to probe mutants'genomic DNA polymorphism compared with ground control by microsatellite markers,three space-induced lines were crossed with a highly susceptible variety LTH,and their F1 and F2 populations were inoculated by two representative blast isolates with broad pathogenicity to analyze their resistance inheritance basis.Meanwhile three mutant lines and the ground control were analyzed by 225 rice SSR(simple sequence repeat)primer pairs selected throughout the 12 chromosomes of whole rice genome,to scan the mutagenesis in genome of the mutant lines.The results indicated the blast-resistant genes harbored in these mutant lines were dominant.It was demonstrated that the resistance of mutant H1 to isolate GD0193 and GD3286 was controlled by a single gene,respectively;while mutants H2 and H3 were controlled by two pairs of major genes against isolate GD3286 and H2 showed complicated genetic mechanism to isolate GD0193.H3's resistance to isolate GD0193 was verified to be controlled by a single gene.According to the results of SSR analysis,three mutant lines showed different mutant rates as compared with the ground control,and the mutant rates also varied.Resistance genes can be induced from rice by space mutation,and different genomic variations were detected in blast-resistant lines.

  4. The influence of the blast furnace slag replacement on chloride penetration in concrete

    Directory of Open Access Journals (Sweden)

    Juan Lizarazo Marriaga

    2011-05-01

    Full Text Available  Corrosion of steel reinforcement due to chloride penetration is the greatest cause of durability problems in concrete; intense international research has been carried out to understand and avoid this. This paper summarises the results of a theoretical and experimental research programme investigating the influence of blast furnace slag on chloride-related transport properties. The relationship between the apparent chloride diffusion coefficient, electrical resistivity and compressive strength was measured. Chloride, hydroxide, sodium and potassium’s intrinsic diffusion coefficients were obtained by using a computational model and an electrical migration test. The initial hydroxide composition of the pore solution, porosity and chloride binding capacity were also determined from the model. The results showed that blast furnace slag improved chloride penetration resistance, resulting in concrete which was less vulnerable to corrosion. 

  5. Refractory Pellet for Hot Blast Stove

    Institute of Scientific and Technical Information of China (English)

    Wang Jing; Peng Xigao

    2011-01-01

    1 Scope This standard specifies the term,definition,classification,specification,technical requirements,test methods,quality appraisal procedures,packing,marking,transportation,storage,and quality certificate of refractory pellet for hot blast stove.This standard is applicable to refractory pellet for hot blast stove.

  6. Blast mitigation experimental and numerical studies

    CERN Document Server

    2013-01-01

    Presents experimental methods of material and structural response to dynamic blast loads Includes computational analysis of material and structural response to dynamic blast loads Offers mitigation measures for structures in various environments Relates lab experiments to larger field tests Features more than 150 illustrations

  7. Fabrication of microstructures by powder blasting

    NARCIS (Netherlands)

    Wensink, H.

    2002-01-01

    This thesis deals with the use of powder blasting as a micromachining technique to create micro systems. Powder blasting is a technology in which small particles, accelerated by an air jet, are directed towards a brittle target for mechanical material removal. It is especially useful for glass

  8. Fabrication of microstructures by powder blasting

    NARCIS (Netherlands)

    Wensink, Hendrik

    2002-01-01

    This thesis deals with the use of powder blasting as a micromachining technique to create micro systems. Powder blasting is a technology in which small particles, accelerated by an air jet, are directed towards a brittle target for mechanical material removal. It is especially useful for glass machi

  9. Laboratory blast wave driven instabilities

    Science.gov (United States)

    Kuranz, Carolyn

    2008-11-01

    This presentation discusses experiments involving the evolution of hydrodynamic instabilities in the laboratory under high-energy-density (HED) conditions. These instabilities are driven by blast waves, which occur following a sudden, finite release of energy, and consist of a shock front followed by a rarefaction wave. When a blast wave crosses an interface with a decrease in density, hydrodynamic instabilities will develop. Instabilities evolving under HED conditions are relevant to astrophysics. These experiments include target materials scaled in density to the He/H layer in SN1987A. About 5 kJ of laser energy from the Omega Laser facility irradiates a 150 μm plastic layer that is followed by a low-density foam layer. A blast wave structure similar to those in supernovae is created in the plastic layer. The blast wave crosses an interface having a 2D or 3D sinusoidal structure that serves as a seed perturbation for hydrodynamic instabilities. This produces unstable growth dominated by the Rayleigh-Taylor (RT) instability in the nonlinear regime. We have detected the interface structure under these conditions using x-ray backlighting. Recent advances in our diagnostic techniques have greatly improved the resolution of our x-ray radiographic images. Under certain conditions, the improved images show some mass extending beyond the RT spike and penetrating further than previously observed or predicted by current simulations. The observed effect is potentially of great importance as a source of mass transport to places not anticipated by current theory and simulation. I will discuss the amount of mass in these spike extensions, the associated uncertainties, and hypotheses regarding their origin We also plan to show comparisons of experiments using single mode and multimode as well as 2D and 3D initial conditions. This work is sponsored by DOE/NNSA Research Grants DE-FG52-07NA28058 (Stewardship Sciences Academic Alliances) and DE-FG52-04NA00064 (National Laser User

  10. Safety of collieries blasting operations

    Energy Technology Data Exchange (ETDEWEB)

    Carbonel, P. (Cerchar, 75 - Paris (France))

    1984-01-01

    The slight increase in periodicity of blasting incidents and their nature have led to remind one of the basic safety principles: to reduce the probability of dust and methane ignition by the explosive used or by the shotfiring line; to carefully select the explosive in accordance to the work to be carried out. It is reminded that using an anti-gassy explosive does not necessarily mean that no ignition will occur.

  11. Detonation safety of blasting caps

    Institute of Scientific and Technical Information of China (English)

    谢兴华; 彭小圣

    2002-01-01

    By means of researching into sympathetic detonation of blasting detonators in air, the regular patterns are concluded from blasting detonators interaction with the shock loading. The aerial distribution of initiating ability of detonators looks like a butterfly. The initiating ability mainly consists of shock wave, explosive gases and fliers. But fundamental questions remain. When does shock wave take the leading role? When and how does the explosive gases or the fliers take function? For those questions, there is less quantitative research. Through the theoretic deduction of the overpressure, the energy calculation of fliers and the experiment of sympathetic detonation of detonators, we can learn the sympathetic detonation distances of several kinds of detonators and make an inquiry into the lateral initiating regulations of detonators. So, we can provide the base data for the research into no sympathetic detonation of herd blasting detonators and then control the detonation between them. Then we can make full use of detonators and reduce the frequency of accidents caused by detonators.

  12. The Next Generation BLAST Experiment

    CERN Document Server

    Galitzki, Nicholas; Angilè, Francesco E; Ashton, Peter; Beall, James A; Becker, Dan; Bradford, Kristi J; Che, George; Cho, Hsiao-Mei; Devlin, Mark J; Dober, Bradley J; Fissel, Laura M; Fukui, Yasuo; Gao, Jiansong; Groppi, Christopher E; Hillbrand, Seth; Hilton, Gene C; Hubmayr, Johannes; Irwin, Kent D; Klein, Jeffrey; Van Lanen, Jeff; Li, Dale; Li, Zhi-Yun; Lourie, Nathan P; Mani, Hamdi; Martin, Peter G; Mauskopf, Philip; Nakamura, Fumitaka; Novak, Giles; Pappas, David P; Pascale, Enzo; Pisano, Giampaolo; Santos, Fabio P; Savini, Giorgio; Scott, Douglas; Stanchfield, Sara; Tucker, Carole; Ullom, Joel N; Underhill, Matthew; Vissers, Michael R; Ward-Thompson, Derek

    2014-01-01

    The Balloon-borne Large Aperture Submillimeter Telescope for Polarimetry (BLASTPol) was a suborbital experiment designed to map magnetic fields in order to study their role in star formation processes. BLASTPol made detailed polarization maps of a number of molecular clouds during its successful flights from Antarctica in 2010 and 2012. We present the next-generation BLASTPol instrument (BLAST-TNG) that will build off the success of the previous experiment and continue its role as a unique instrument and a test bed for new technologies. With a 16-fold increase in mapping speed, BLAST-TNG will make larger and deeper maps. Major improvements include a 2.5 m carbon fiber mirror that is 40% wider than the BLASTPol mirror and ~3000 polarization sensitive detectors. BLAST-TNG will observe in three bands at 250, 350, and 500 microns. The telescope will serve as a pathfinder project for microwave kinetic inductance detector (MKID) technology, as applied to feedhorn coupled submillimeter detector arrays. The liquid he...

  13. IED blast postconcussive syncope and autonomic dysregulation.

    Science.gov (United States)

    Sams, Richard; LaBrie, D Walter; Norris, Jacob; Schauer, Judy; Frantz, Earl

    2012-01-01

    Concussions are the most frequent battle injury sustained in Afghanistan. The Concussion Restoration Care Center provides multidisciplinary care to concussed service members in theater. The Concussion Restoration Care Center has managed over 500 concussions, the majority being from improvised explosive device (IED) blasts. Syncope following a concussion without a loss of consciousness is rarely reported in the literature. The pathophysiology of concussion from a blast injury may be distinct from a concussion secondary to blunt trauma. Two cases of syncope following concussions with an alteration of consciousness are presented, and a mechanism of action is proposed. Post-IED blast concussive symptom frequency at initial presentation on a cohort of patients is reported, with 1.3% of patients experiencing postconcussive syncope. Syncope following an IED blast may be related to centrally mediated autonomic dysregulation at the brain stem level. Syncope should be added to the list of possible symptoms that occur following concussions, in particular concussions following a blast injury.

  14. Numerical Simulation for Blast Analysis of Insulating Glass in a Curtain Wall

    Science.gov (United States)

    Deng, Rong-bing; Jin, Xian-long

    2010-04-01

    This article presents a three-dimensional numerical simulation method for blast response calculation of insulating glass in a curtain wall based on multi-material arbitrary Lagrangian-Eulerian (ALE) formulation and high-performance computer. The whole analytical model consists of explosion, air, curtain wall system, and ground. In particular, detailed components including insulating glass panels, aluminum column, silicone sealant, and other parts in the curtain wall are set up in terms of actual size and actual assembly. This model takes account of the coupling between blast and structure, nonlinear material behavior, brittle failure of glass material, and non-reflecting boundary definition. Final calculation has been performed on the Dawning 4000A supercomputer using the finite-element code LS-DYNA 971 MPP. The propagation of shock wave in air and blast-structure interaction is quite well estimated by numerical calculation. The damage regions of outer and inner glass are reproduced in the numerical simulations, which are in agreement with the experimental observations. The result provides a global understanding of insulating glass panels under blast loading in the curtain wall system. It may be generated to supplement experimental studies for developing appropriate design guidelines for curtain wall systems as well.

  15. Fluid dynamics of the 1997 Boxing Day volcanic blast on Montserrat, West Indies

    Science.gov (United States)

    Esposti Ongaro, T.; Clarke, A. B.; Neri, A.; Voight, B.; Widiwijayanti, C.

    2008-03-01

    Directed volcanic blasts are powerful explosions with a significant laterally directed component, which can generate devastating, high-energy pyroclastic density currents (PDCs). Such blasts are an important class of eruptive phenomena, but quantified understanding of their dynamics and effects is still incomplete. Here we use 2-D and 3-D multiparticle thermofluid dynamic flow codes to examine a powerful volcanic blast that occurred on Montserrat in December 1997. On the basis of the simulations, we divide the blast into three phases: an initial burst phase that lasts roughly 5 s and involves rapid expansion of the gas-pyroclast mixture, a gravitational collapse phase that occurs when the erupted material fails to mix with sufficient air to form a buoyant column and thus collapses asymmetrically, and a PDC phase that is dominated by motion parallel to the ground surface and is influenced by topography. We vary key input parameters such as total gas energy and total solid mass to understand their influence on simulations, and we compare the simulations with independent field observations of damage and deposits, demonstrating that the models generally capture important large-scale features of the natural phenomenon. We also examine the 2-D and 3-D model results to estimate the flow Mach number and conclude that the range of damage sustained at villages on Montserrat can be reasonably explained by the spatial and temporal distribution of the dynamic pressure associated with subsonic PDCs.

  16. Device, system and method for a sensing electrical circuit

    Science.gov (United States)

    Vranish, John M. (Inventor)

    2009-01-01

    The invention relates to a driven ground electrical circuit. A driven ground is a current-measuring ground termination to an electrical circuit with the current measured as a vector with amplification. The driven ground module may include an electric potential source V.sub.S driving an electric current through an impedance (load Z) to a driven ground. Voltage from the source V.sub.S excites the minus terminal of an operational amplifier inside the driven ground which, in turn, may react by generating an equal and opposite voltage to drive the net potential to approximately zero (effectively ground). A driven ground may also be a means of passing information via the current passing through one grounded circuit to another electronic circuit as input. It may ground one circuit, amplify the information carried in its current and pass this information on as input to the next circuit.

  17. Quarry blasts assessment and their environmental impacts on the nearby oil pipelines, southeast of Helwan City, Egypt

    Directory of Open Access Journals (Sweden)

    Adel M.E. Mohamed

    2013-06-01

    Full Text Available Ground vibrations induced by blasting in the cement quarries are one of the fundamental problems in the quarrying industry and may cause severe damage to the nearby utilities and pipelines. Therefore, a vibration control study plays an important role in the minimization of environmental effects of blasting in quarries. The current paper presents the influence of the quarry blasts at the National Cement Company (NCC on the two oil pipelines of SUMED Company southeast of Helwan City, by measuring the ground vibrations in terms of Peak Particle Velocity (PPV. The seismic refraction for compressional waves deduced from the shallow seismic survey and the shear wave velocity obtained from the Multi channel Analysis of Surface Waves (MASW technique are used to evaluate the closest site of the two pipelines to the quarry blasts. The results demonstrate that, the closest site of the two pipelines is of class B, according to the National Earthquake Hazard Reduction Program (NEHRP classification and the safe distance to avoid any environmental effects is 650 m, following the deduced Peak Particle Velocity (PPV and scaled distance (SD relationship (PPV = 700.08 × SD−1.225 in mm/s and the Air over Pressure (air blast formula (air blast = 170.23 × SD−0.071 in dB. In the light of prediction analysis, the maximum allowable charge weight per delay was found to be 591 kg with damage criterion of 12.5 mm/s at the closest site of the SUMED pipelines.

  18. Evaluation of human response to blasting vibration from excavation of a large scale rock slope: A case study

    Science.gov (United States)

    Yan, Peng; Lu, Wenbo; Zhang, Jing; Zou, Yujun; Chen, Ming

    2017-04-01

    Ground vibration, as the most critical public hazard of blasting, has received much attention from the community. Many countries established national standards to suppress vibration impact on structures, but a world-accepted blasting vibration criterion on human safety is still missing. In order to evaluate human response to the vibration from blasting excavation of a large-scale rock slope in China, this study aims to suggest a revised criterion. The vibration frequency was introduced to improve the existing single-factor (peak particle velocity) standard recommended by the United States Bureau of Mines (USBM). The feasibility of the new criterion was checked based on field vibration monitoring and investigation of human reactions. Moreover, the air overpressure or blast effects on human beings have also been discussed. The result indicates that the entire zone of influence can be divided into three subzones: severe-annoyance, light-annoyance and perception zone according to the revised safety standard. Both the construction company and local residents have provided positive comments on this influence degree assessment, which indicates that the presented criterion is suitable for evaluating human response to nearby blasts. Nevertheless, this specific criterion needs more field tests and verifications before it can be

  19. Planetary Atmospheric Electricity

    CERN Document Server

    Leblanc, F; Yair, Y; Harrison, R. G; Lebreton, J. P; Blanc, M

    2008-01-01

    This volume presents our contemporary understanding of atmospheric electricity at Earth and in other solar system atmospheres. It is written by experts in terrestrial atmospheric electricity and planetary scientists. Many of the key issues related to planetary atmospheric electricity are discussed. The physics presented in this book includes ionisation processes in planetary atmospheres, charge generation and separation, and a discussion of electromagnetic signatures of atmospheric discharges. The measurement of thunderstorms and lightning, including its effects and hazards, is highlighted by articles on ground and space based instrumentation, and new missions.Theory and modelling of planetary atmospheric electricity complete this review of the research that is undertaken in this exciting field of space science. This book is an essential research tool for space scientists and geoscientists interested in electrical effects in atmospheres and planetary systems. Graduate students and researchers who are new to t...

  20. Blast Valve Design and Related Studies : A Review

    Directory of Open Access Journals (Sweden)

    P. K. Sharma

    2016-04-01

    Full Text Available The protective structures required for performing critical operations are vulnerable to the blast and shock loads of advanced weapons. A blast valve is an important component of such structures for ventilation during normal conditions and for protection from blast/ shock during explosion. In this paper, various aspects of blast valve design and related studies are briefly reviewed. The concept and effects of blast wave, blast impact, numerical modelling and deformation of circular plate (one of the critical components of blast valve have been discussed. The merits and demerits of sensing mechanisms viz. remote and direct sensing are discussed. The leakage of blast pressure during finite closing period of the valve (one of the critical problems and the shock tube as a major experimental facility for testing of blast valves are briefly discussed.

  1. 46 CFR 183.372 - Equipment and conductor grounding.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Equipment and conductor grounding. 183.372 Section 183... conductor grounding. (a) All metallic enclosures and frames of electrical equipment must be permanently... equipment must be bonded together to a common ground by a normally non-current carrying conductor....

  2. 49 CFR 229.97 - Grounding fuel tanks.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Grounding fuel tanks. 229.97 Section 229.97 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Equipment § 229.97 Grounding fuel tanks. Fuel tanks and related piping shall be electrically grounded....

  3. 30 CFR 56.12026 - Grounding transformer and switchgear enclosures.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Grounding transformer and switchgear enclosures... MINES Electricity § 56.12026 Grounding transformer and switchgear enclosures. Metal fencing and metal buildings enclosing transformers and switchgear shall be grounded....

  4. 30 CFR 57.12026 - Grounding transformer and switchgear enclosures.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Grounding transformer and switchgear enclosures... NONMETAL MINES Electricity Surface and Underground § 57.12026 Grounding transformer and switchgear enclosures. Metal fencing and metal buildings enclosing transformers and switchgear shall be grounded....

  5. Blast Injuries: From Improvised Explosive Device Blasts to the Boston Marathon Bombing.

    Science.gov (United States)

    Singh, Ajay K; Ditkofsky, Noah G; York, John D; Abujudeh, Hani H; Avery, Laura A; Brunner, John F; Sodickson, Aaron D; Lev, Michael H

    2016-01-01

    Although most trauma centers have experience with the imaging and management of gunshot wounds, in most regions blast wounds such as the ones encountered in terrorist attacks with the use of improvised explosive devices (IEDs) are infrequently encountered outside the battlefield. As global terrorism becomes a greater concern, it is important that radiologists, particularly those working in urban trauma centers, be aware of the mechanisms of injury and the spectrum of primary, secondary, tertiary, and quaternary blast injury patterns. Primary blast injuries are caused by barotrauma from the initial increased pressure of the explosive detonation and the rarefaction of the atmosphere immediately afterward. Secondary blast injuries are caused by debris carried by the blast wind and most often result in penetrating trauma from small shrapnel. Tertiary blast injuries are caused by the physical displacement of the victim and the wide variety of blunt or penetrating trauma sustained as a result of the patient impacting immovable objects such as surrounding cars, walls, or fences. Quaternary blast injuries include all other injuries, such as burns, crush injuries, and inhalational injuries. Radiography is considered the initial imaging modality for assessment of shrapnel and fractures. Computed tomography is the optimal test to assess penetrating chest, abdominal, and head trauma. The mechanism of blast injuries and the imaging experience of the victims of the Boston Marathon bombing are detailed, as well as musculoskeletal, neurologic, gastrointestinal, and pulmonary injury patterns from blast injuries.

  6. Establishment and Application of a Set of Material System for Studying the Resistance to Blast in Rice

    Institute of Scientific and Technical Information of China (English)

    LI Xiao-fang; LUO Wen-yong; XIAO Xin; MAO Xing-xue; LIU Yan-zhuo

    2003-01-01

    The study used Waixuan35, a blast resistant rice material adopted widely previously in South China, Yuexiangzhan, a rice variety with the largest planting area in Guangdong Province at present and with the characteristics of horizontal blast resistance and high harvest index, and Qisizhan, the earliest good eating quality variety in Guangdong Province as parent materials, and created an important material systems for studying agricultural characters such as rice blast resistance genes, their resistance mechanisms and quality by hybridization offspring single grain transfer method and DNA hybridization method, namely recombination inbred line RIL, extend recombination inbred line ERIL and transferred-mutant recombination inbred line TRIL assemblages. In RIL assemblage, various materials of resistance gene combinations for identifying rice blast pathogen strains had been identified from the material system, providing direct material evidence for gene to gene theory. Using the same control and same method, in ERIL assemblage, it was proved that there were several main resistance genes and several minor resistance genes in horizontal resistant Yuexiangzhan,providing preliminary evidences for multigene control in horizontal resistance. A set of stable material assemblage for studying future horizontal resistance had been created. A mutation material of Yuexiangzhan from horizontal resistance to vertical resistance was obtained by wild rice external DNA electric stimulation introduction, and variation in mutation assemblage was certified by SSLP. These studies and materials provided important new materials for studying rice blast resistance mechanisms, gene cloning, resistance genes especially horizontal resistance.

  7. Lipid Mediators and Human Leukemic Blasts

    Directory of Open Access Journals (Sweden)

    Rémi Fiancette

    2011-01-01

    Full Text Available Some of the most potent inflammatory mediators share a lipid origin. They regulate a wide spectrum of cellular processes including cell proliferation and apoptosis. However, the precise roles and ways (if any in which these compounds impact the growth and apoptosis of leukemic blasts remain incompletely resolved. In spite of this, significant advances have been recently made. Here we briefly review the current knowledge about the production of lipid mediators (prostaglandins, leukotrienes, platelet-activating factor by leukemic blasts, the enzymatic activities (phospholipase A2, cyclooxygenases, lipoxygenases involved in their productions and their effects (through specific membrane bound receptors on the growth, and apoptosis of leukemic blasts.

  8. Peak Overpressures for Internal Blast

    Science.gov (United States)

    1979-06-01

    condensed into relatively simple algebraic equa- tions for the (logarithm of the) equilibrium constant of formation as a function of absolute...blast for three conventional fuels-benzene, JP-4 (a hydrocarbon fuel with an empirical formula C9H17 ), and ethylene oxide-are plotted as a function of...256 .26 9.4 6.36 2166 7.89 2666 .27 Cubica . 9.5 6.66 2244 7.91 2591 .13 0.028 9.7 6.51 2197 7.97 2801 .19 9.9 6.17 2090 8.01 2607 .23 9.9 7.59 2495

  9. Blast Wave Experiments at Z

    Science.gov (United States)

    2007-06-01

    radiation flows upward, it passes though a 1.7-mm high, tapered, 25-μm thick gold wall cone that is filled 20 ± 3 mg/cm3 silica aerogel (SiO2). Above...this cone is a 20 ± 3 mg/cm3 silica aerogel filled, 1-mm high, 2.4-mm inner diameter, 25-μm thick gold wall cylinder. On the cylinder rests a 4-mm...diameter gold platform that supports a higher density (40-60 mg/cm3) silica aerogel . This aerogel is the region where the blast wave forms after

  10. Preparation of Ceramic-Bonded Carbon Block for Blast Furnace

    Science.gov (United States)

    Li, Yiwei; Li, Yawei; Sang, Shaobai; Chen, Xilai; Zhao, Lei; Li, Yuanbing; Li, Shujing

    2014-01-01

    Traditional carbon blocks for blast furnaces are mainly produced with electrically calcined anthracite owing to its good hot metal corrosion resistance. However, this kind of material shows low thermal conductivity and does not meet the demands for cooling of the hearth and the bottom of blast furnaces. In this article, a new kind of a high-performance carbon block has been prepared via ceramic-bonded carbon (CBC) technology in a coke bed at 1673 K (1400 °C) using artificial graphite aggregate, alumina, metallic aluminum, and silicon powders as starting materials. The results showed that artificial graphite aggregates were strongly bonded by the three-dimensional network of ceramic phases in carbon blocks. In this case, the good resistance of the CBC blocks against erosion/corrosion by the hot metal is provided by the ceramic matrix and the high thermal conductivity by the graphite aggregates. The microstructure of this carbon block resembles that of CBC composites with a mean pore size of less than 0.1 μm, and up to 90 pct of the porosity shows a pore size <1 μm. Its thermal conductivity is higher than 30 W · m-1 · K-1 [293 K (20 °C)]. Meanwhile, its hot metal corrosion resistance is better than that of traditional carbon blocks.

  11. BLAST-EXPLORER helps you building datasets for phylogenetic analysis

    Directory of Open Access Journals (Sweden)

    Claverie Jean-Michel

    2010-01-01

    Full Text Available Abstract Background The right sampling of homologous sequences for phylogenetic or molecular evolution analyses is a crucial step, the quality of which can have a significant impact on the final interpretation of the study. There is no single way for constructing datasets suitable for phylogenetic analysis, because this task intimately depends on the scientific question we want to address, Moreover, database mining softwares such as BLAST which are routinely used for searching homologous sequences are not specifically optimized for this task. Results To fill this gap, we designed BLAST-Explorer, an original and friendly web-based application that combines a BLAST search with a suite of tools that allows interactive, phylogenetic-oriented exploration of the BLAST results and flexible selection of homologous sequences among the BLAST hits. Once the selection of the BLAST hits is done using BLAST-Explorer, the corresponding sequence can be imported locally for external analysis or passed to the phylogenetic tree reconstruction pipelines available on the Phylogeny.fr platform. Conclusions BLAST-Explorer provides a simple, intuitive and interactive graphical representation of the BLAST results and allows selection and retrieving of the BLAST hit sequences based a wide range of criterions. Although BLAST-Explorer primarily aims at helping the construction of sequence datasets for further phylogenetic study, it can also be used as a standard BLAST server with enriched output. BLAST-Explorer is available at http://www.phylogeny.fr

  12. Silica Brick for Hot Blast Stove

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ 1 Scope This standard specifies the glossary and definition, marking, shape and dimension, technical requirements, test method, quality appraisal procedure, packing, label, transportation, storage and quality certification of silica brick for hot blast stove.

  13. Fireclay Refractory Bricks for Hot Blast Stove

    Institute of Scientific and Technical Information of China (English)

    Wang Jing; Zhang Yongfang; Chai Junlan

    2008-01-01

    @@ 1 Scope This standard specifies the classification, shape, dimension, technical requirements, test method,inspection rules, packing, marking,transportation,storage and quality certification of fireclay refractory bricks for hot blast stove.

  14. Material Systems for Blast-Energy Dissipation

    Energy Technology Data Exchange (ETDEWEB)

    James Schondel; Henry S. Chu

    2010-10-01

    Lightweight panels have been designed to protect buildings and vehicles from blast pressures by activating energy dissipation mechanisms under the influence of blast loading. Panels were fabricated which featured a variety of granular materials and hydraulic dissipative deformation mechanisms and the test articles were subjected to full-scale blast loading. The force time-histories transmitted by each technology were measured by a novel method that utilized inexpensive custom-designed force sensors. The array of tests revealed that granular materials can effectively dissipate blast energy if they are employed in a way that they easily crush and rearrange. Similarly, hydraulic dissipation can effectively dissipate energy if the panel features a high fraction of porosity and the panel encasement features low compressive stiffness.

  15. Blast vulnerability assessment : challenges and myths

    Energy Technology Data Exchange (ETDEWEB)

    Braimah, A.; Contestabile, E. [Natural Resources Canada, Ottawa, ON (Canada). Canadian Explosives Research Laboratory

    2007-07-01

    Challenges related to the creation of a comprehensive blast vulnerability assessment program for Canadian buildings was presented. Many building owners are now seeking to assess the vulnerability of their structures to blast loads, and wish to increase the survivability of both occupants and structures. However, the engineering community has not yet incorporated existing physical security measures into comprehensive mitigation strategies and designs. Different institutions are currently using varying amounts of explosives in vulnerability assessments, and there is an urgent need for information on terrorist capabilities in both the present and the future. Pressure-impulse diagrams are now used by engineers to assess component responses to blasts. However, pressure-impulse diagrams are based on single modes of failure, and may not be capable of capturing all failure modes of building components, nor are they able to ensure that vulnerability assessments do not overestimate the blast load resistance of buildings.

  16. Anhydrous Taphole Mix for Blast Furnace

    Institute of Scientific and Technical Information of China (English)

    Yu Lingyan

    2010-01-01

    @@ 1 Scope This standard specifies the term,definition,brand,label,technical requirements,test methods,quality appraisal procedures,packing,marking,transportation,storage,and quality certificate of anhydrous taphole mix for blast furnace.

  17. Kaolinite Refractory Bricks for Blast Furnaces

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    @@ This standard is suitable to the fireclay bricks for blast furnace. 1 Classification, Shape and Dimension 1 According to physical and chemical indexes, the brick can be divided into two trademarks: ZGN-42 and GN-42.

  18. Basic Local Alignment Search Tool (BLAST)

    Data.gov (United States)

    U.S. Department of Health & Human Services — BLAST finds regions of similarity between biological sequences. The program compares nucleotide or protein sequences to sequence databases and calculates the...

  19. Study on compressive strength of self compacting mortar cubes under normal & electric oven curing methods

    Science.gov (United States)

    Prasanna Venkatesh, G. J.; Vivek, S. S.; Dhinakaran, G.

    2017-07-01

    In the majority of civil engineering applications, the basic building blocks were the masonry units. Those masonry units were developed as a monolithic structure by plastering process with the help of binding agents namely mud, lime, cement and their combinations. In recent advancements, the mortar study plays an important role in crack repairs, structural rehabilitation, retrofitting, pointing and plastering operations. The rheology of mortar includes flowable, passing and filling properties which were analogous with the behaviour of self compacting concrete. In self compacting (SC) mortar cubes, the cement was replaced by mineral admixtures namely silica fume (SF) from 5% to 20% (with an increment of 5%), metakaolin (MK) from 10% to 30% (with an increment of 10%) and ground granulated blast furnace slag (GGBS) from 25% to 75% (with an increment of 25%). The ratio between cement and fine aggregate was kept constant as 1: 2 for all normal and self compacting mortar mixes. The accelerated curing namely electric oven curing with the differential temperature of 128°C for the period of 4 hours was adopted. It was found that the compressive strength obtained from the normal and electric oven method of curing was higher for self compacting mortar cubes than normal mortar cube. The cement replacement by 15% SF, 20% MK and 25%GGBS obtained higher strength under both curing conditions.

  20. Brain Injury Risk from Primary Blast

    Science.gov (United States)

    2012-02-29

    injury has been studied extensively in air-containing organs such as the lungs , gastrointestinal tract, and ear due to their increased...veterans (Owens, 2008). Primary blast injury has been studied extensively in air-containing organs such as the lungs , gastrointestinal tract, and ear... contusions typically on or around the brainstem though there were no skull fractures for any blast intensity. Risk functions were developed that

  1. The Effects of Underwater Blast on Divers

    Science.gov (United States)

    2007-11-02

    bladder, including hepatic tear can cause referred right shoulder pain. Transient paralysis in the lower limbs, testicular pain, nausea, vomiting...blast trauma . This is probably because most immersion blast has been studied with heads above the water, 24 sinus injury is unlikely to threaten life and...without impediment. Close to the explosive source, however; there is violent trauma to the rib-cage, chest and abdominal contents, and limb fractures

  2. Research on Effects of Blast Casting Vibration and Vibration Absorption of Presplitting Blasting in Open Cast Mine

    Directory of Open Access Journals (Sweden)

    Li Ma

    2016-01-01

    Full Text Available The impact energy produced by blast casting is able to break and cast rocks, yet the strong vibration effects caused at the same time would threaten the safety of mines. Based on the theory of Janbu’s Limit Equilibrium Method (LEM, pseudo-static method has been incorporated to analyze the influence of dynamic loads of blasting on slope stability. The horizontal loads produced by blast vibrations cause an increase in sliding forces, and this leads to a lower slope stability coefficient. When the tensile stresses of the two adjacent blast holes are greater than the tensile strength of rock mass, the radical oriented cracks are formed, which is the precondition for the formation of presplit face. Thus, the formula for calculating the blast hole spacing of presplit blasting can be obtained. Based on the analysis of the principles of vibration tester and vibration pick-up in detecting blast vibrations, a detection scheme of blast vibration is worked out by taking the blast area with precrack rear and non-precrack side of the detection object. The detection and research results of blast vibration show that presplit blasting can reduce the attenuation coefficient of stress wave by half, and the vibration absorption ratio could reach 50.2%; the impact of dynamic loads on the end-wall slope stability coefficient is 1.98%, which proves that presplit blasting plays an important role in shock absorption of blast casting.

  3. Electricity Customers

    Science.gov (United States)

    This page discusses key sectors and how they use electricity. Residential, commercial, and industrial customers each account for roughly one-third of the nation’s electricity use. The transportation sector also accounts for a small fraction of electricity.

  4. Reduction of sidewall inclination and blast lag of powder blasted channels

    NARCIS (Netherlands)

    Wensink, Henk; Elwenspoek, Miko C.

    2002-01-01

    Powder blasting (abrasive jet machining) is a fast directional machining technique for brittle materials like silicon and glass. The cross-section of a powder blasted channel has a rounded V-shape. These inclined sidewalls are caused by the typical impact angle dependent removal rate for brittle mat

  5. Design and commissioning of a semi-confined blast chamber

    Institute of Scientific and Technical Information of China (English)

    I.M. SNYMAN; F.J. MOSTERT; W. GRUNDLING

    2016-01-01

    This paper presents the design, test and analysis of a scaled cylindrical blast chamber. The blast chamber is a one-fifth dimensional size replica of the full-scale blast chamber (Emily). The blast chamber is semi-confined as one end is open. The scaled blast chamber is used to test concepts for closing the open end and allows the gas to vent at the same time. ANSYS AUTODYN calculated the pressure time histories for different closure scenarios. Comparing the results suggested a viable scenario, namely a structure consisting of a circular disc and a frame positioned at the open end of the blast chamber. The structure and cylindrical blast chamber were subjected to scaled blast tests and the pressure results are presented and discussed.

  6. Information modeling system for blast furnace control

    Science.gov (United States)

    Spirin, N. A.; Gileva, L. Y.; Lavrov, V. V.

    2016-09-01

    Modern Iron & Steel Works as a rule are equipped with powerful distributed control systems (DCS) and databases. Implementation of DSC system solves the problem of storage, control, protection, entry, editing and retrieving of information as well as generation of required reporting data. The most advanced and promising approach is to use decision support information technologies based on a complex of mathematical models. The model decision support system for control of blast furnace smelting is designed and operated. The basis of the model system is a complex of mathematical models created using the principle of natural mathematical modeling. This principle provides for construction of mathematical models of two levels. The first level model is a basic state model which makes it possible to assess the vector of system parameters using field data and blast furnace operation results. It is also used to calculate the adjustment (adaptation) coefficients of the predictive block of the system. The second-level model is a predictive model designed to assess the design parameters of the blast furnace process when there are changes in melting conditions relative to its current state. Tasks for which software is developed are described. Characteristics of the main subsystems of the blast furnace process as an object of modeling and control - thermal state of the furnace, blast, gas dynamic and slag conditions of blast furnace smelting - are presented.

  7. 46 CFR 111.05-17 - Generation and distribution system grounding.

    Science.gov (United States)

    2010-10-01

    ... Section 111.05-17 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Equipment Ground, Ground Detection, and Grounded Systems § 111.05-17... neutral bus permanently connected to the neutral bus on the main switchboard; and (3) No switch,...

  8. SparkBLAST: scalable BLAST processing using in-memory operations.

    Science.gov (United States)

    de Castro, Marcelo Rodrigo; Tostes, Catherine Dos Santos; Dávila, Alberto M R; Senger, Hermes; da Silva, Fabricio A B

    2017-06-27

    The demand for processing ever increasing amounts of genomic data has raised new challenges for the implementation of highly scalable and efficient computational systems. In this paper we propose SparkBLAST, a parallelization of a sequence alignment application (BLAST) that employs cloud computing for the provisioning of computational resources and Apache Spark as the coordination framework. As a proof of concept, some radionuclide-resistant bacterial genomes were selected for similarity analysis. Experiments in Google and Microsoft Azure clouds demonstrated that SparkBLAST outperforms an equivalent system implemented on Hadoop in terms of speedup and execution times. The superior performance of SparkBLAST is mainly due to the in-memory operations available through the Spark framework, consequently reducing the number of local I/O operations required for distributed BLAST processing.

  9. A Table-top Blast Driven Shock Tube

    OpenAIRE

    Courtney, Michael; Courtney, Amy

    2011-01-01

    The prevalence of blast-induced traumatic brain injury in conflicts in Iraq and Afghanistan has motivated laboratory scale experiments on biomedical effects of blast waves and studies of blast wave transmission properties of various materials in hopes of improving armor design to mitigate these injuries. This paper describes the design and performance of a table-top shock tube that is more convenient and widely accessible than traditional compression driven and blast driven shock tubes. The d...

  10. Temporal Progression of Visual Injury from Blast Exposure

    Science.gov (United States)

    2016-09-01

    sample was then separated into three equal tubes. FIGURE 1. PRESSURE-TIME HISTORY AT LOCATION OF ANIMAL PLACEMENT WITHIN BLAST TUBE SB3C2015...exposed to blast between 2007-12  Complete first set of 40 animal blast experiments CY14 Goals – Animal testing, service member studies  Complete data...analysis from retrospective study  Enrollment, interviews, and ocular examination of service members  Complete animal blast experiments  Complete

  11. Alkahest NuclearBLAST : a user-friendly BLAST management and analysis system

    Directory of Open Access Journals (Sweden)

    Burke Mark

    2005-06-01

    Full Text Available Abstract Background - Sequencing of EST and BAC end datasets is no longer limited to large research groups. Drops in per-base pricing have made high throughput sequencing accessible to individual investigators. However, there are few options available which provide a free and user-friendly solution to the BLAST result storage and data mining needs of biologists. Results - Here we describe NuclearBLAST, a batch BLAST analysis, storage and management system designed for the biologist. It is a wrapper for NCBI BLAST which provides a user-friendly web interface which includes a request wizard and the ability to view and mine the results. All BLAST results are stored in a MySQL database which allows for more advanced data-mining through supplied command-line utilities or direct database access. NuclearBLAST can be installed on a single machine or clustered amongst a number of machines to improve analysis throughput. NuclearBLAST provides a platform which eases data-mining of multiple BLAST results. With the supplied scripts, the program can export data into a spreadsheet-friendly format, automatically assign Gene Ontology terms to sequences and provide bi-directional best hits between two datasets. Users with SQL experience can use the database to ask even more complex questions and extract any subset of data they require. Conclusion - This tool provides a user-friendly interface for requesting, viewing and mining of BLAST results which makes the management and data-mining of large sets of BLAST analyses tractable to biologists.

  12. A blast absorber test: measurement and model results

    NARCIS (Netherlands)

    Eerden, F.J.M. van der; Berg, F. van den; Hof, J. van 't; Arkel, E. van

    2006-01-01

    A blast absorber test was conducted at the Aberdeen Test Centre from 13 to 17 June 2005. The test was set up to determine the absorbing and shielding effect of a gravel pile, of 1.5 meters high and 15 by 15 meters wide, on blasts from large weapons: e.g. armor, artillery or demolition. The blast was

  13. 30 CFR 56.6300 - Control of blasting operations.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Control of blasting operations. 56.6300 Section... § 56.6300 Control of blasting operations. (a) Only persons trained and experienced in the handling and use of explosive material shall direct blasting operations and related activities. (b) Trainees...

  14. 30 CFR 57.6300 - Control of blasting operations.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Control of blasting operations. 57.6300 Section... Transportation-Surface and Underground § 57.6300 Control of blasting operations. (a) Only persons trained and experienced in the handling and use of explosive material shall direct blasting operations and...

  15. 30 CFR 816.64 - Use of explosives: Blasting schedule.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Use of explosives: Blasting schedule. 816.64... ACTIVITIES § 816.64 Use of explosives: Blasting schedule. (a) General requirements. (1) The operator shall conduct blasting operations at times approved by the regulatory authority and announced in the...

  16. 30 CFR 57.22607 - Blasting on shift (III mines).

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Blasting on shift (III mines). 57.22607 Section... Standards for Methane in Metal and Nonmetal Mines Explosives § 57.22607 Blasting on shift (III mines). When blasting on shift, tests for methane shall be made in the mine atmosphere by a competent person...

  17. 30 CFR 75.1310 - Explosives and blasting equipment.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Explosives and blasting equipment. 75.1310... SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Explosives and Blasting § 75.1310 Explosives and blasting equipment. (a) Only permissible explosives, approved sheathed explosive units,...

  18. 30 CFR 57.6306 - Loading, blasting, and security.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Loading, blasting, and security. 57.6306... Transportation-Surface and Underground § 57.6306 Loading, blasting, and security. (a) When explosive materials or... blasting operation and the activities of surveying, stemming, sampling of geology, and reopening of...

  19. Experimental Validation of the Butyl-Rubber Finite Element (FE) Material Model for the Blast-Mitigating Floor Mat

    Science.gov (United States)

    2015-08-01

    environment. I also would like to thank the members of the Blast Protection Branch and its specialists for supporting the numerical analysis , experiment...each signal in the postprocessing on the data- analysis software (MathWorks, MATLAB ). The test was also recorded by the high-speed imaging camera...AGENCY NAME(S) AND ADDRESS(ES) Survivability and Firepower Analysis Section, Ballistic Research Division, Ground Systems Research Center ATTN: Masayuki

  20. Cygnus Loop Supernova Blast Wave

    Science.gov (United States)

    1993-01-01

    This is an image of a small portion of the Cygnus Loop supernova remnant, which marks the edge of a bubble-like, expanding blast wave from a colossal stellar explosion, occurring about 15,000 years ago. The HST image shows the structure behind the shock waves, allowing astronomers for the first time to directly compare the actual structure of the shock with theoretical model calculations. Besides supernova remnants, these shock models are important in understanding a wide range of astrophysical phenomena, from winds in newly-formed stars to cataclysmic stellar outbursts. The supernova blast is slamming into tenuous clouds of insterstellar gas. This collision heats and compresses the gas, causing it to glow. The shock thus acts as a searchlight revealing the structure of the interstellar medium. The detailed HST image shows the blast wave overrunning dense clumps of gas, which despite HST's high resolution, cannot be resolved. This means that the clumps of gas must be small enough to fit inside our solar system, making them relatively small structures by interstellar standards. A bluish ribbon of light stretching left to right across the picture might be a knot of gas ejected by the supernova; this interstellar 'bullet' traveling over three million miles per hour (5 million kilometres) is just catching up with the shock front, which has slowed down by ploughing into interstellar material. The Cygnus Loop appears as a faint ring of glowing gases about three degrees across (six times the diameter of the full Moon), located in the northern constellation, Cygnus the Swan. The supernova remnant is within the plane of our Milky Way galaxy and is 2,600 light-years away. The photo is a combination of separate images taken in three colors, oxygen atoms (blue) emit light at temperatures of 30,000 to 60,000 degrees Celsius (50,000 to 100,000 degrees Farenheit). Hydrogen atoms (green) arise throughout the region of shocked gas. Sulfur atoms (red) form when the gas cools to

  1. Battery Lifetime Analysis and Simulation Tool (BLAST) Documentation

    Energy Technology Data Exchange (ETDEWEB)

    Neubauer, J.

    2014-12-01

    The deployment and use of lithium-ion batteries in automotive and stationary energy storage applications must be optimized to justify their high up-front costs. Given that batteries degrade with use and storage, such optimizations must evaluate many years of operation. As the degradation mechanisms are sensitive to temperature, state-of-charge histories, current levels, and cycle depth and frequency, it is important to model both the battery and the application to a high level of detail to ensure battery response is accurately predicted. To address these issues, the National Renewable Energy Laboratory has developed the Battery Lifetime Analysis and Simulation Tool (BLAST) suite of tools. This suite of tools pairs NREL's high-fidelity battery degradation model with a battery electrical and thermal performance model, application-specific electrical and thermal performance models of the larger system (e.g., an electric vehicle), application-specific system use data (e.g., vehicle travel patterns and driving data), and historic climate data from cities across the United States. This provides highly realistic, long-term predictions of battery response and thereby enables quantitative comparisons of varied battery use strategies.

  2. Battery Lifetime Analysis and Simulation Tool (BLAST) Documentation

    Energy Technology Data Exchange (ETDEWEB)

    Neubauer, J. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-12-01

    The deployment and use of lithium-ion (Li-ion) batteries in automotive and stationary energy storage applications must be optimized to justify their high up-front costs. Given that batteries degrade with use and storage, such optimizations must evaluate many years of operation. As the degradation mechanisms are sensitive to temperature, state-of-charge (SOC) histories, current levels, and cycle depth and frequency, it is important to model both the battery and the application to a high level of detail to ensure battery response is accurately predicted. To address these issues, the National Renewable Energy Laboratory (NREL) has developed the Battery Lifetime Analysis and Simulation Tool (BLAST) suite. This suite of tools pairs NREL’s high-fidelity battery degradation model with a battery electrical and thermal performance model, application-specific electrical and thermal performance models of the larger system (e.g., an electric vehicle), application-specific system use data (e.g., vehicle travel patterns and driving data), and historic climate data from cities across the United States. This provides highly realistic long-term predictions of battery response and thereby enables quantitative comparisons of varied battery use strategies.

  3. FastBLAST: homology relationships for millions of proteins.

    Directory of Open Access Journals (Sweden)

    Morgan N Price

    Full Text Available BACKGROUND: All-versus-all BLAST, which searches for homologous pairs of sequences in a database of proteins, is used to identify potential orthologs, to find new protein families, and to provide rapid access to these homology relationships. As DNA sequencing accelerates and data sets grow, all-versus-all BLAST has become computationally demanding. METHODOLOGY/PRINCIPAL FINDINGS: We present FastBLAST, a heuristic replacement for all-versus-all BLAST that relies on alignments of proteins to known families, obtained from tools such as PSI-BLAST and HMMer. FastBLAST avoids most of the work of all-versus-all BLAST by taking advantage of these alignments and by clustering similar sequences. FastBLAST runs in two stages: the first stage identifies additional families and aligns them, and the second stage quickly identifies the homologs of a query sequence, based on the alignments of the families, before generating pairwise alignments. On 6.53 million proteins from the non-redundant Genbank database ("NR", FastBLAST identifies new families 25 times faster than all-versus-all BLAST. Once the first stage is completed, FastBLAST identifies homologs for the average query in less than 5 seconds (8.6 times faster than BLAST and gives nearly identical results. For hits above 70 bits, FastBLAST identifies 98% of the top 3,250 hits per query. CONCLUSIONS/SIGNIFICANCE: FastBLAST enables research groups that do not have supercomputers to analyze large protein sequence data sets. FastBLAST is open source software and is available at http://microbesonline.org/fastblast.

  4. COMPARATIVE ANALYSIS OF GROUNDING RESISTANCE VALUE IN SOIL AND SEPTICTANK

    Directory of Open Access Journals (Sweden)

    Abdul Syakur

    2012-02-01

    Full Text Available The aim of grounding system to protect of electrical equipment and instrumentation system and peopletogether. The lightning stroke near the strucutre of building can damage of equipment and instrumentationsystem. Therefore, it is very important to protect theese electrical and electronic equipment from lightningstrike uses lightning protection system and grounding system.This paper presents kind of grounding system at type of soil and place. The measurement of groundingresistance in soil and septictank have done. Types of soil for grounding resistance measuring aremarshland, clay and rockland.The measurement results of grounding resistance show that value of grounding resistance depend ondeepness of electrode and kind of soil and septictank. Grounding resistance value in septictank is morelower than soil.

  5. A New Method of Grounding Grid Design

    Directory of Open Access Journals (Sweden)

    Feng Zhen-Bao

    2016-01-01

    Full Text Available In order to equalize the electric potential distribution of the grounding grid surface, and improve the safety level of the grounding grid, method for optimal arrangement of conducts in the grounding grid is proposed in this paper. The calculation results about maximum touch voltages and mesh potentials show that the method can reduce touch voltage and equilibrium surface potential. It is shown that the design of the grounding grid is related to not only the soil environment, but also the rectangular shape. Comparing with other methods, the method proposed in the paper can reduce maximum touch voltage about 12%. This method also can be applied in a uniform and non-uniform soil, rectangular and square grounding grids. The optimize effect meets the related standards of the power industry.

  6. Vibration velocity and frequency of underwater short-hole blasting

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Based on the measuring data of underwater blasting vibrationand the regression analysis results of these data, two formulae usually used of blasting vibration velocity were compared. Factors that canaffect blasting vibration and frequency were summarized and analyzed.It is thought that the effect of the number of freedom face and burden direction on blasting vibration should be considered during blastingdesign. Based on the relevant research results and the regression results of these data, a formula to calculate under water blasting frequency was put forward.

  7. Conceptual design and simulation analysis of thermal behaviors of TGR blast furnace and oxygen blast furnace

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Extensive use of carbon based fuel is the main inducement for global warming and more extreme weather.Reducing carbon dioxide emission and enhancing energy use is a common subject in steel industry.In the integrated steel plant,decreasing carbon dioxide emission must consider energy balance in the whole iron and steel works,and secondary energy must be actively utilized.As promising blast-furnaces,top gas recovery blast furnace(TGR-BF) and oxygen blast furnace have been investigated.In this paper,conceptual TGR blast furnace and oxygen blast furnace are proposed.Base on the idea of blast furnace gas de-CO2 circulating as reducing agent and the idea of pure oxygen blast decreasing the thermal reserve zone temperature,process modeling is conducted with ASPEN Plus.It is shown that the developed model reasonably describes the energy balance and mass balance feature of the furnace,and provides basic thermodynamic condition for furnaces.The effects of changes in different operation conditions are studied by sensitivity analysis and reference data from simulation.

  8. Divide and Conquer (DC BLAST: fast and easy BLAST execution within HPC environments

    Directory of Open Access Journals (Sweden)

    Won Cheol Yim

    2017-06-01

    Full Text Available Bioinformatics is currently faced with very large-scale data sets that lead to computational jobs, especially sequence similarity searches, that can take absurdly long times to run. For example, the National Center for Biotechnology Information (NCBI Basic Local Alignment Search Tool (BLAST and BLAST+ suite, which is by far the most widely used tool for rapid similarity searching among nucleic acid or amino acid sequences, is highly central processing unit (CPU intensive. While the BLAST suite of programs perform searches very rapidly, they have the potential to be accelerated. In recent years, distributed computing environments have become more widely accessible and used due to the increasing availability of high-performance computing (HPC systems. Therefore, simple solutions for data parallelization are needed to expedite BLAST and other sequence analysis tools. However, existing software for parallel sequence similarity searches often requires extensive computational experience and skill on the part of the user. In order to accelerate BLAST and other sequence analysis tools, Divide and Conquer BLAST (DCBLAST was developed to perform NCBI BLAST searches within a cluster, grid, or HPC environment by using a query sequence distribution approach. Scaling from one (1 to 256 CPU cores resulted in significant improvements in processing speed. Thus, DCBLAST dramatically accelerates the execution of BLAST searches using a simple, accessible, robust, and parallel approach. DCBLAST works across multiple nodes automatically and it overcomes the speed limitation of single-node BLAST programs. DCBLAST can be used on any HPC system, can take advantage of hundreds of nodes, and has no output limitations. This freely available tool simplifies distributed computation pipelines to facilitate the rapid discovery of sequence similarities between very large data sets.

  9. Evolution of blast wave profiles in simulated air blasts: experiment and computational modeling

    Science.gov (United States)

    Chandra, N.; Ganpule, S.; Kleinschmit, N. N.; Feng, R.; Holmberg, A. D.; Sundaramurthy, A.; Selvan, V.; Alai, A.

    2012-09-01

    Shock tubes have been extensively used in the study of blast traumatic brain injury due to increased incidence of blast-induced neurotrauma in Iraq and Afghanistan conflicts. One of the important aspects in these studies is how to best replicate the field conditions in the laboratory which relies on reproducing blast wave profiles. Evolution of the blast wave profiles along the length of the compression-driven air shock tube is studied using experiments and numerical simulations with emphasis on the shape and magnitude of pressure time profiles. In order to measure dynamic pressures of the blast, a series of sensors are mounted on a cylindrical specimen normal to the flow direction. Our results indicate that the blast wave loading is significantly different for locations inside and outside of the shock tube. Pressure profiles inside the shock tube follow the Friedlander waveform fairly well. Upon approaching exit of the shock tube, an expansion wave released from the shock tube edges significantly degrades the pressure profiles. For tests outside the shock tube, peak pressure and total impulse reduce drastically as we move away from the exit and majority of loading is in the form of subsonic jet wind. In addition, the planarity of the blast wave degrades as blast wave evolves three dimensionally. Numerical results visually and quantitatively confirm the presence of vortices, jet wind and three-dimensional expansion of the planar blast wave near the exit. Pressure profiles at 90° orientation show flow separation. When cylinder is placed inside, this flow separation is not sustained, but when placed outside the shock tube this flow separation is sustained which causes tensile loading on the sides of the cylinder. Friedlander waves formed due to field explosives in the intermediate-to far-field ranges are replicated in a narrow test region located deep inside the shock tube.

  10. Effectiveness of eye armor during blast loading.

    Science.gov (United States)

    Bailoor, Shantanu; Bhardwaj, Rajneesh; Nguyen, Thao D

    2015-11-01

    Ocular trauma is one of the most common types of combat injuries resulting from the interaction of military personnel with improvised explosive devices. Ocular blast injury mechanisms are complex, and trauma may occur through various injury mechanisms. However, primary blast injuries (PBI) are an important cause of ocular trauma that may go unnoticed and result in significant damage to internal ocular tissues and visual impairment. Further, the effectiveness of commonly employed eye armor, designed for ballistic and laser protection, in lessening the severity of adverse blast overpressures (BOP) is unknown. In this paper, we employed a three-dimensional (3D) fluid-structure interaction computational model for assessing effectiveness of the eye armor during blast loading on human eyes and validated results against free field blast measurements by Bentz and Grimm (2013). Numerical simulations show that the blast waves focused on the ocular region because of reflections from surrounding facial features and resulted in considerable increase in BOP. We evaluated the effectiveness of spectacles and goggles in mitigating the pressure loading using the computational model. Our results corroborate experimental measurements showing that the goggles were more effective than spectacles in mitigating BOP loading on the eye. Numerical results confirmed that the goggles significantly reduced blast wave penetration in the space between the armor and the eyes and provided larger clearance space for blast wave expansion after penetration than the spectacles. The spectacles as well as the goggles were more effective in reducing reflected BOP at higher charge mass because of the larger decrease in dynamic pressures after the impact. The goggles provided greater benefit of reducing the peak pressure than the spectacles for lower charge mass. However, the goggles resulted in moderate, sustained elevated pressure loading on the eye, that became 50-100% larger than the pressure loading

  11. Implementation of top turbine of blast furnace 3 - USIMINAS Ipatinga; Implantacao da turbina de topo do alto-forno 3 - USIMINAS Unidade Ipatinga

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Murilo Alves Tito de; Rosa, Ericson Rimen Ribeiro; Oliveira, Claudiney Freitas de [Usinas Siderurgicas de Minas Gerais S/A (USIMINAS), Ipatinga, MG (Brazil)

    2010-07-01

    The use of turbine for energy recovery from top gas from blast furnace is aligned with the strategic objectives of USIMINAS Ipatinga to increase their own power generation, reduce environmental impacts and improve operational control of pressure from the top. This study aimed to present the progress in controlling the top pressure and electric power generation using turbine drawing gas kinetic energy. Will be addressed by developing methods used to control the pressure of the top from the start of operation of Blast Furnace 3 to the present day. Will also be discussed operating procedures and expected performance. (author)

  12. Ground water and energy

    Energy Technology Data Exchange (ETDEWEB)

    1980-11-01

    This national workshop on ground water and energy was conceived by the US Department of Energy's Office of Environmental Assessments. Generally, OEA needed to know what data are available on ground water, what information is still needed, and how DOE can best utilize what has already been learned. The workshop focussed on three areas: (1) ground water supply; (2) conflicts and barriers to ground water use; and (3) alternatives or solutions to the various issues relating to ground water. (ACR)

  13. Blasting practices in a quarry with karstic cavities

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The blasting practices in a limestone quarry with karstic cavities have been presented. The existence of karstic cavities in the quarry has reduced blasting efficiency significantly. In order to improve blasting efficiency different blasting strategies (loading holes with ANFO in plastic bag, recording cavity location along the holes and charging the holes according to this information, and modifying blasting pattern according to karstic cavities) had been implemented and the results were evaluated on per ton cost basis. It was concluded that efficient blasting in such aquarries requires determining the size and shape of karstic cavities and based on this information, to modify the blast pattern and charge the holes. The suggested method is to record the cavity along the drill hole and to generate 3D model of cavities. By doing this, the production cost in the limestone quarry has decreased from 0.407 $/t to 0.354 $/t.

  14. Blast-induced traumatic brain injury: a new trend of blast injury research

    Institute of Scientific and Technical Information of China (English)

    Yan Zhao; Zheng-Guo Wang

    2015-01-01

    Blast injury has become the major life-and function-threatening injuries in recent warfares.There is increased research interest in the mental disorders caused by blast-induced traumatic brain injury (bTBI),which has been proved as one of the "signature wounds" in modern battlefield.We reviewed the recent progresses in bTBl-related researches and concluded that the new era of blast injury research has shifted from the traditional physical impairments to cognitive dysfunctional/mental disorders that are proved to be more related to the outcome of combat casualty care.

  15. 46 CFR 98.25-85 - Electrical bonding.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Electrical bonding. 98.25-85 Section 98.25-85 Shipping... § 98.25-85 Electrical bonding. (a) Each cargo tank shall be electrically grounded to the hull. The.... This electrical connection shall be maintained until after the cargo hose has been disconnected and...

  16. Neuropsychological outcome from blast versus non-blast: mild traumatic brain injury in U.S. military service members.

    Science.gov (United States)

    Lange, Rael T; Pancholi, Sonal; Brickell, Tracey A; Sakura, Sara; Bhagwat, Aditya; Merritt, Victoria; French, Louis M

    2012-05-01

    The purpose of this study was to compare the neuropsychological outcome from blast-related versus non-blast related mild traumatic brain injury (MTBI). Participants were 56 U.S. military service members who sustained an MTBI, divided into two groups based on mechanism of injury: (a) non-blast related (Non-blast; n = 21), and (b) blast plus secondary blunt trauma (Blast Plus; n = 35). All participants had sustained their injury in theatre whilst deployed during Operation Iraqi Freedom or Operation Enduring Freedom. Patients had been seen for neuropsychological evaluation at Walter Reed Army Medical Center on average 4.4 months (SD = 4.1) post-injury. Measures included 14 clinical scales from the Personality Assessment Inventory (PAI) and 12 common neurocognitive measures. For the PAI, there were no significant differences between groups on all scales (p > .05). However, medium effect sizes were found for the Depression (d = .49) and Stress (d = .47) scales (i.e., Blast Plus > Non-blast). On the neurocognitive measures, after controlling for the influence of psychological distress (i.e., Depression, Stress), there were no differences between the Non-blast and Blast Plus groups on all measures. These findings provide little evidence to suggest that blast exposure plus secondary blunt trauma results in worse cognitive or psychological recovery than blunt trauma alone. (JINS, 2012, 18, 595-605).

  17. quality of computerized blast load simulation for non-linear dynamic ...

    African Journals Online (AJOL)

    STRANCOM

    purpose, commercial software system ... the analysis model of choice and the stand-off ... This paper addresses the blast-load simulation .... effectively design structures under blast loads. .... Fig. 4: Distribution of Blast Load on Structural Elements.

  18. Electrical, Electronic, and Electromechanical (EEE) Parts Management and Control Requirements for Space Flight Hardware and Critical Ground Support Equipment...aka... The NASA EEE Parts Standard, NASA-STD 8739.10

    Science.gov (United States)

    Majewicz, Peter; Sampson, Michael

    2016-01-01

    Describes development and content of a new NASA Standard for Electrical Electronic and Electromechanical (EEE) parts. This Standard reflects current practices, instead of changing them. Most NASA Centers utilize local documents, but there is minimal consistency across the Agency. A gap analysis clearly shows the differences that exist among the different centers and with respect to the NASA Parts Policy. Once approved, the new standard can be referenced in contracts and agreements with organizations outside of NASA.

  19. Blast Diffusion by Different Shapes of Domes

    Directory of Open Access Journals (Sweden)

    Ram Ranjan Sahu

    2015-03-01

    Full Text Available Domes have been used since ancient times in constructions. These are effective structures in supporting loads for large span. Dome has an added advantage of having good looking in structural applications. Many shapes of domes are being used nowadays for residential, commercial, and industrial purposes. Specific purpose domes are also used for nuclear containment. Main threats to structures are from the bomb blast. Hence, domes too are to be designed to withstand effectively the pressure energy generated by the blast. A comparative theoretical study is proposed on the different shapes of domes having same weight and thickness. Various responses are estimated through numerical method after simulating blast and comparing their intensities.Defence Science Journal, Vol. 65, No. 1, January 2015, pp.77-82, DOI:http://dx.doi.org/10.14429/dsj.65.6908

  20. Electric Power

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ China Council for the Promotion of International Trade Electric Power Industry Office (CCPIT Electric Power), one of the pro-fessional industrial branches of China Council for the Promotion of International Trade (CCPIT), was established in 2006.

  1. Electricity economics

    CERN Document Server

    Hu, Zhaoguang

    2013-01-01

    Systematically analyzing for the first time the production output from electricity consumption for enterprises, sectors, and industries, this study uses the function of EAI (electricity as input), and includes national E-GDP figures for more than 20 countries.

  2. Complexity analysis of blast-induced vibrations in underground mining:A case study

    Institute of Scientific and Technical Information of China (English)

    Cardu Marilena; Dompieri Mauricio; Seccatore Jacopo

    2012-01-01

    Blasting in geological bodies is an industrial process acting in an environment characterized by high uncertainties (natural joints,faults,voids,abrupt structural changes),which are transposed into the process parameters (e.g.energetic transfer to rock mass,hole deviations,misfires,vibrations,fly-rock,etc.).The approach to this problem searching for the "optimum" result can be ineffective.The geological environment is marked out by too many uncertainties,to have an "optimum" suitable to different applications.Researching for "Robustness" in a blast design gives rise to much more efficiency.Robustness is the capability of the system to behave constantly under varying conditions,without leading to unexpected results.Since the geology varies from site to site,setting a robust method can grant better results in varying environments,lowering the costs and increasing benefits and safety.Complexity Analysis (C.A.) is an innovative approach to systems.C.A.allows analyzing the Complexity of the Blast System and the criticality of each variable (drilling,charging and initiation parameters).The lower is the complexity,the more robust is the system,and the lower is the possibility of unexpected results.The paper presents the results obtained thanks to the C.A.approach in an underground gypsum quarry (Italy),exploited by conventional rooms and pillars method by drilling and blasting.The application of C.A.led to a reliable solution to reduce the charge per delay,hence reducing the impact of ground vibration on the surrounding structures.The analysis of the correlation degree between the variables allowed recognizing empirical laws as well.

  3. Dielectric properties of Al2O3 coatings deposited via atmospheric plasma spraying and dry-ice blasting correlated with microstructural characteristics

    Science.gov (United States)

    Dong, Shujuan; Song, Bo; Liao, Hanlin; Coddet, Christian

    2015-01-01

    In this work, atmospheric plasma spraying combined with dry-ice blasting have been used to prepare alumina (Al2O3) coatings designed for insulating applications. The microstructural characteristics and dielectric properties of Al2O3 coatings were presented. The electrical insulating properties, i.e., dielectric strength and breakdown voltage, were investigated by dielectric breakdown test using direct current and alternating current. Relationships between dielectric properties and coating characteristics were discussed. The results showed that dry-ice blasting used during atmospheric plasma spray process allowed the production of coatings with better dielectric properties than those prepared without dry-ice blasting. The dielectric properties were correlated with the microstructural characteristics, not with phase composition.

  4. Reproduction of an animal model of landmine blast injuries

    Directory of Open Access Journals (Sweden)

    Sen ZHANG

    2014-03-01

    Full Text Available Objective To reproduce an animal model of landmine blast injuries for studying its mechanism and characteristics. Methods Fifteen healthy New Zealand white rabbits (body weight 1.9-2.4 kg were prepared as experimental animals. Punctiform burster was used to simulate the landmine, and it was electrically detonated far away to produce landmine blast injuries on unilateral hind limb of rabbits in upright state. The vital signs before and 5min, 15min, 30min, 45min, 1h, 2h, 3h, 6h, 9h and 12h after injuries were recorded. Autopsy of dead animals was performed immediately and the survivors were sacrificed for pathological examination 6h and 12h after the injury. Macroscopic and microscopic changes in the injured limb and distant organs were observed. Fifteen random adult body weights were generated by random number table, and the explosive energy of M14 landmine (about 29g TNT explosive energy was simulated, to compare the ratio of explosive force equivalent to weight calculated between experimental animals and randomly selected adults. Results No significant change in blood pressure was observed at different time points before and after injuries. A broom-like change was found in the injured limb by the general observation. The subareas and pathological changes of injured limb coincided with the typical limb injuries produced by landmine explosion. Damage in different degrees was found in distant organs, and the wound characteristics and injury of major organs were in accordance with the reports of relevant literature. The ratio of explosive equivalent to weight of experimental animals (0.50±0.04g TNT/kg was similar to that of randomly selected adults (0.51±0.05g TNT/kg. Conclusion The present animal model could simulate the landmine explosive injuries, and may be used in research of landmine explosive injuries. DOI: 10.11855/j.issn.0577-7402.2014.01.14

  5. Improved blasting results with precise initiation:Numerical simulation of sublevel caving blasting

    OpenAIRE

    Yi, Changping

    2013-01-01

    A series of numerical simulations of rock blasting using LS-DYNA software havebeen conducted to investigate the effect of short delay time on the fragmentation inunderground mines. The purpose was to test the hypothesis proposed by Rossmaniththat stress wave interaction could result in finer fragmentation by controlling theinitiation times. The blasted rock was simulated with RHT material model. After thecalculation, the elements with damage level above 0.6 were removed to simulate thefractur...

  6. Blast-Induced Acceleration in a Shock Tube: Distinguishing Primary and Tertiary Blast Injury

    Science.gov (United States)

    2014-10-01

    Annual, Year 2 3. DATES COVERED 4. TITLE AND SUBTITLE Blast-Induced Acceleration in a Shock Tube : Distinguishing Primary and Tertiary 5a...Using a highly characterized shock tube simulation of blast, rats will be exposed to BOP with varied peak amplitudes and impulse in association...understanding of the relation of the former to the latter. As the use of shock tubes has greatly expanded in recent years for biomedical research

  7. Mathematical model and software for control of commissioning blast furnace

    Science.gov (United States)

    Spirin, N. A.; Onorin, O. P.; Shchipanov, K. A.; Lavrov, V. V.

    2016-09-01

    Blowing-in is a starting period of blast furnace operation after construction or major repair. The current approximation methods of blowing-in burden analysis are based on blowing-in practice of previously commissioned blast furnaces. This area is theoretically underexplored; there are no common scientifically based methods for selection of the burden composition and blast parameters. The purpose of this paper is development and scientific substantiation of the methods for selection of the burden composition and blast parameters in the blast furnace during the blowing-in period. Research methods are based on physical regularities of main processes running in the blast furnace, system analysis, and application of modern principles for development and construction of mathematical models, algorithms and software designed for automated control of complex production processes in metallurgy. As consequence of the research made by the authors the following results have been achieved: 1. A set of mathematical models for analysis of burden arrangement throughout the height of the blast furnace and for selection of optimal blast and gas dynamic parameters has been developed. 2. General principles for selection of the blowing-in burden composition and blast and gas dynamic parameters have been set up. 3. The software for the engineering and process staff of the blast furnace has been developed and introduced in the industry.

  8. Acute Blast Injury Reduces Brain Abeta in Two Rodent Species

    Directory of Open Access Journals (Sweden)

    Rita eDe Gasperi

    2012-12-01

    Full Text Available Blast-induced traumatic brain injury (TBI has been a major cause of morbidity and mortality in the conflicts in Iraq and Afghanistan. How the primary blast wave affects the brain is not well understood. In particular, it is unclear whether blast injures the brain through mechanisms similar to those found in non-blast closed impact injuries (nbTBI. The β-amyloid (Aβ peptide associated with the development of Alzheimer’s disease (AD is elevated acutely following TBI in humans as well as in experimental animal models of nbTBI. We examined levels of brain Aβ following experimental blast injury using enzyme-linked immunosorbent assays for Aβ 40 and 42. In both rat and mouse models of blast injury, rather than being increased, endogenous rodent brain Aβ levels were decreased acutely following injury. Levels of the amyloid precursor protein (APP were increased following blast exposure although there was no evidence of axonal pathology based on APP immunohistochemical staining. Unlike the findings in nbTBI animal models, levels of the β-secretase, BACE-1, and the γ-secretase component presenilin-1 were unchanged following blast exposure. These studies have implications for understanding the nature of blast injury to the brain. They also suggest that strategies aimed at lowering Aβ production may not be effective for treating acute blast injury to the brain.

  9. SUPPORTING PROCEDURE AND FIELD MEASUREMENT IN THE SHAFT THROUGH GLIDING TECTONIC GROUND

    Institute of Scientific and Technical Information of China (English)

    XIAJianzhong; TENGNianbao

    1995-01-01

    The paper describes mechanical properties and deformation features of shaft adjoining rocks in gliding tectonic ground and presents the shaft-fupporting procedure of smooth-wall cushion blasting ,preliminary bolting and shotcreting and pouring reinforced concrete liner in one-time-whole-section in the basis of adjoining rock deformations measured dynamically in site ,Field measurements of the pressure exerted on shaft wall show that this supporting procedure has enough safety reserve to meet the safety repuirements in mining production.

  10. Electric drives

    CERN Document Server

    Boldea, Ion

    2005-01-01

    ENERGY CONVERSION IN ELECTRIC DRIVESElectric Drives: A DefinitionApplication Range of Electric DrivesEnergy Savings Pay Off RapidlyGlobal Energy Savings Through PEC DrivesMotor/Mechanical Load MatchMotion/Time Profile MatchLoad Dynamics and StabilityMultiquadrant OperationPerformance IndexesProblemsELECTRIC MOTORS FOR DRIVESElectric Drives: A Typical ConfigurationElectric Motors for DrivesDC Brush MotorsConventional AC MotorsPower Electronic Converter Dependent MotorsEnergy Conversion in Electric Motors/GeneratorsPOWER ELECTRONIC CONVERTERS (PECs) FOR DRIVESPower Electronic Switches (PESs)The

  11. Electrical contracting

    CERN Document Server

    Neidle, Michael

    2013-01-01

    Electrical Contracting, Second Edition is a nine-chapter text guide for the greater efficiency in planning and completing installations for the design, installation and control of electrical contracts. This book starts with a general overview of the efficient cabling and techniques that must be employed for safe wiring design, as well as the cost estimation of the complete electrical contract. The subsequent chapters are devoted to other electrical contracting requirements, including electronic motor control, lighting, and electricity tariffs. A chapter focuses on the IEE Wiring Regulations an

  12. Development of Semi—Graphite Carbon—Silicon Carbide Brick and Its Application in Slag Forming Zone of Large—sized Blast Furnace

    Institute of Scientific and Technical Information of China (English)

    HAOYun-zhong; CHENQian-wan

    1994-01-01

    Based on the damage mechanism of the lining at the slag forming zone of the blast furnace and the charactieristics of various refractory ma-terials,the methods to increase the service life of the lining at the slag forming zone have been found:(1) to improve the capacity of the blast furnace brick lining subjet to heat impact;(2) to reduce the working side temperature of the brick lining.On this basis,the semi-graphitized ,high temperature electrically calcined anthracite and silicon carbide etc ,were used as the main raw materials,Through a lot of experiments the proper raw material mix and grain size compo-sition were determined,In addition ,a suitable amount of additives and binders was added.After high pressur forming,high temperature firing and grinding ,the semi-graphitic carbon-silicon carbide bricks with close dimension tler-ances and ideal physical and chemical properties have been made.They have been applied in some blast furnaces,such as No.11(2580 m3) and No.6(1050 m3) blast furnaces etc.at Anshan Iron and Steel Company,and the problem of short service life at slag forming zone of blast furnace has been solved.

  13. Distinguishing Realistic Military Blasts from Firecrackers in Mitigation Studies of Blast Induced Traumatic Brain Injury

    Energy Technology Data Exchange (ETDEWEB)

    Moss, W C; King, M J; Blackman, E G

    2011-01-21

    In their Contributed Article, Nyein et al. (1,2) present numerical simulations of blast waves interacting with a helmeted head and conclude that a face shield may significantly mitigate blast induced traumatic brain injury (TBI). A face shield may indeed be important for future military helmets, but the authors derive their conclusions from a much smaller explosion than typically experienced on the battlefield. The blast from the 3.16 gm TNT charge of (1) has the following approximate peak overpressures, positive phase durations, and incident impulses (3): 10 atm, 0.25 ms, and 3.9 psi-ms at the front of the head (14 cm from charge), and 1.4 atm, 0.32 ms, and 1.7 psi-ms at the back of a typical 20 cm head (34 cm from charge). The peak pressure of the wave decreases by a factor of 7 as it traverses the head. The blast conditions are at the threshold for injury at the front of the head, but well below threshold at the back of the head (4). The blast traverses the head in 0.3 ms, roughly equal to the positive phase duration of the blast. Therefore, when the blast reaches the back of the head, near ambient conditions exist at the front. Because the headform is so close to the charge, it experiences a wave with significant curvature. By contrast, a realistic blast from a 2.2 kg TNT charge ({approx} an uncased 105 mm artillery round) is fatal at an overpressure of 10 atm (4). For an injury level (4) similar to (1), a 2.2 kg charge has the following approximate peak overpressures, positive phase durations, and incident impulses (3): 2.1 atm, 2.3 ms, and 18 psi-ms at the front of the head (250 cm from charge), and 1.8 atm, 2.5 ms, and 16.8 psi-ms at the back of the head (270 cm from charge). The peak pressure decreases by only a factor of 1.2 as it traverses the head. Because the 0.36 ms traversal time is much smaller than the positive phase duration, pressures on the head become relatively uniform when the blast reaches the back of the head. The larger standoff implies

  14. Electric vehicles

    Science.gov (United States)

    1990-03-01

    Quiet, clean, and efficient, electric vehicles (EVs) may someday become a practical mode of transportation for the general public. Electric vehicles can provide many advantages for the nation's environment and energy supply because they run on electricity, which can be produced from many sources of energy such as coal, natural gas, uranium, and hydropower. These vehicles offer fuel versatility to the transportation sector, which depends almost solely on oil for its energy needs. Electric vehicles are any mode of transportation operated by a motor that receives electricity from a battery or fuel cell. EVs come in all shapes and sizes and may be used for different tasks. Some EVs are small and simple, such as golf carts and electric wheel chairs. Others are larger and more complex, such as automobile and vans. Some EVs, such as fork lifts, are used in industries. In this fact sheet, we will discuss mostly automobiles and vans. There are also variations on electric vehicles, such as hybrid vehicles and solar-powered vehicles. Hybrid vehicles use electricity as their primary source of energy, however, they also use a backup source of energy, such as gasoline, methanol or ethanol. Solar-powered vehicles are electric vehicles that use photovoltaic cells (cells that convert solar energy to electricity) rather than utility-supplied electricity to recharge the batteries. These concepts are discussed.

  15. ELECTRICAL TECHNIQUES FOR ENGINEERING APPLICATIONS.

    Science.gov (United States)

    Bisdorf, Robert J.

    1985-01-01

    Surface electrical geophysical methods have been used in such engineering applications as locating and delineating shallow gravel deposits, depth to bedrock, faults, clay zones, and other geological phenomena. Other engineering applications include determining water quality, tracing ground water contaminant plumes and locating dam seepages. Various methods and electrode arrays are employed to solve particular geological problems. The sensitivity of a particular method or electrode array depends upon the physics on which the method is based, the array geometry, the electrical contrast between the target and host materials, and the depth to the target. Each of the available electrical methods has its own particular advantages and applications which the paper discusses.

  16. Fast Prediction of Blast Damage from Airbursts: An Empirical Monte Carlo approach

    Science.gov (United States)

    Brown, Peter G.; Stokan, Ed

    2016-10-01

    The February 15, 2013 Chelyabinsk airburst was the first modern bolide whose associated shockwave caused blast damage at the ground (Popova et al., 2013). Near-Earth Object (NEO) impacts in the Chelyabinsk-size range (~20 m) are expected to occur every few decades (Boslough et al., 2015) and therefore we expect ground damage from meteoric airbursts to be the next planetary defense threat to be confronted. With pre-impact detections of small NEOs certain to become more common, decision makers will be faced with estimating blast damage from impactors with uncertain physical properties on short timescales.High fidelity numerical bolide entry models have been developed in recent years (eg. Boslough and Crawford, 2008; Shuvalov et al., 2013), but the wide range in a priori data about strength, fragmentation behavior, and other physical properties for a specific impactor make predictions of bolide behavior difficult. The long computational running times for hydrocode models make the exploration of a wide parameter space challenging in the days to hours before an actual impact.Our approach to this problem is to use an analytical bolide entry model, the triggered-progressive fragmentation model (TPFM) developed by ReVelle (2005) within a Monte Carlo formalism. In particular, we couple this model with empirical constraints on the statistical spread in strength for meter-scale impactors from Brown et al (2015) based on the observed height at maximum bolide brightness. We also use the correlation of peak bolide brightness with total energy as given by Brown (2016) as a proxy for fragmentation behaviour. Using these constraints, we are able to quickly generate a large set of realizations of probable bolide energy deposition curves and produce simple estimates of expected blast damage using existing analytical relations.We validate this code with the known parameters of the Chelyabinsk airburst and explore how changes to the entry conditions of the observed bolide may have

  17. Modeling of Near-Field Blast Performance

    Science.gov (United States)

    2013-11-01

    The freeze-out temperature is chosen by comparison of calorimetry experiments (2, 3) and thermoequilibrium calculations using CHEETAH (4). The near...P.; Vitello, P. CHEETAH Users Manual; Lawrence Livermore National Laboratory: Livermore, CA, 2012. 5. Walter, P. Introduction to Air Blast

  18. Carbon monoxide exposure in blast furnace workers.

    Science.gov (United States)

    Lewis, S; Mason, C; Srna, J

    1992-09-01

    This study investigated the occupational exposure to carbon monoxide (CO) of a group of blast furnace workers from an integrated steelworks, compared to a control group having no significant occupational CO exposure from other areas in the same works. The study was undertaken in 1984 at Port Kembla, New South Wales. Carboxyhaemoglobin (COHb) levels before and after an eight-hour work shift were measured in 98 male steelworkers: 52 from two CO-exposed iron blast furnaces and 46 controls from production areas in the same steelworks. The sample was stratified by smoking habits. Environmental air CO levels had been found to be consistently higher on one furnace than on the other. Absorption of CO from the working environment occurred in workers on the blast furnace with higher CO levels, regardless of smoking habits. On this blast furnace, some readings of COHb levels after a workshift in nonsmokers approached the proposed Australian occupational limit of 5 per cent COHb saturation. Overall, workers with the highest occupational exposure who smoked most heavily had the highest absorption of CO over a work shift. Biological monitoring gives an accurate measure of individual worker 'dose' of CO from all sources. Both environmental monitoring and biological monitoring need to be included as part of a program for controlling occupational CO exposure.

  19. An experimental investigation of blast driven turbulence

    Science.gov (United States)

    Musci, Benjamin; Ranjan, Devesh

    2016-11-01

    In the Georgia Tech Shock and Advanced Mixing Lab, a facility is being built to study blast driven turbulence. Motivated by the discrepancies observed between actual and modeled supernovae, this facility aims to resolve the important spatial scales in the extensive mixing of the outer layers. These outer layers will be modeled by subjecting two-three gases of varying density to a blast wave generated by Exploding Bridge Wires. The blast wave's interaction with perturbations at the gaseous, membrane-less, interfaces will induce the Richtmeyer-Meshkov or Rayleigh Taylor Instability, depending on the acceleration history and perturbation amplitude. Through the use of simultaneous Particle Image Velocimetry, and Planar Laser Induced Fluorescence, this project aims to determine the effect of interface initial conditions on turbulence. A 2D Diverging Wedge and 3D Diverging Conical Tube are being built to enable repeatable blast-wave production, continuous optical viewing of the flow, reproducible multi-layer interface creation, and the collection of simultaneous density-velocity measurements to directly measure turbulent quantities. The preliminary analysis informing the design of this facility, the construction progress, and updates on newly realized design constraints are presented.

  20. Developments in vapour cloud explosion blast modeling

    NARCIS (Netherlands)

    Mercx, W.P.M.; Berg, A.C. van den; Hayhurst, C.J.; Robertson, N.J.; Moran, K.C.

    2000-01-01

    TNT Equivalency methods are widely used for vapour cloud explosion blast modeling. Presently, however, other types of models are available which do not have the fundamental objections TNT Equivalency models have. TNO Multi-Energy method is increasingly accepted as a more reasonable alternative to be

  1. The radiological management of bomb blast injury.

    Science.gov (United States)

    Hare, S S; Goddard, I; Ward, P; Naraghi, A; Dick, E A

    2007-01-01

    A need to understand the nature and patterns of bomb blast injury, particularly in confined spaces, has come to the fore with the current worldwide threat from terrorism. The purpose of this review article is to familiarize the radiologist with the imaging they might expect to see in a mass casualty terrorist event, illustrated by examples from two of the main institutions receiving patients from the London Underground tube blasts of 7 July 2005. We present examples of injuries that are typical in blast victims, as well as highlighting some blast sequelae that might also be found in other causes of multiple trauma. This should enable the radiologist to seek out typical injuries, including those that may not be initially clinically apparent. Terror-related injuries are often more severe than those seen in other trauma cases, and multi-system trauma at distant anatomical sites should be anticipated. We highlight the value of using a standardized imaging protocol to find clinically undetected traumatic effects and include a discussion on management of multiple human and non-human flying fragments. This review also discusses the role of radiology in the management and planning for a mass casualty terrorist incident and the optimal deployment of radiographic services during such an event.

  2. Media selection for micro blasting medical parts.

    Science.gov (United States)

    Whelan, T

    2008-10-01

    Micro blasting is used in a range of applications including catheter, stent and pacemaker manufacturing. The correct media to use for the required surface is defined here together with some of the finer points of the process to ensure successful results.

  3. 46 CFR 111.05-15 - Neutral grounding.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Neutral grounding. 111.05-15 Section 111.05-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL... propulsion, power, lighting, or distribution system having a neutral bus or conductor must have the...

  4. Hybrid Turbine Electric Vehicle

    Science.gov (United States)

    Viterna, Larry A.

    1997-01-01

    Hybrid electric power trains may revolutionize today's ground passenger vehicles by significantly improving fuel economy and decreasing emissions. The NASA Lewis Research Center is working with industry, universities, and Government to develop and demonstrate a hybrid electric vehicle. Our partners include Bowling Green State University, the Cleveland Regional Transit Authority, Lincoln Electric Motor Division, the State of Ohio's Department of Development, and Teledyne Ryan Aeronautical. The vehicle will be a heavy class urban transit bus offering double the fuel economy of today's buses and emissions that are reduced to 1/10th of the Environmental Protection Agency's standards. At the heart of the vehicle's drive train is a natural-gas-fueled engine. Initially, a small automotive engine will be tested as a baseline. This will be followed by the introduction of an advanced gas turbine developed from an aircraft jet engine. The engine turns a high-speed generator, producing electricity. Power from both the generator and an onboard energy storage system is then provided to a variable-speed electric motor attached to the rear drive axle. An intelligent power-control system determines the most efficient operation of the engine and energy storage system.

  5. Experimental study of blast mitigating devices based on combined construction

    Science.gov (United States)

    Takayama, K.; Silnikov, M. V.; Chernyshov, M. V.

    2016-09-01

    A robust blast inhibiting bin is the most often used device for damage blast effects suppression. In particular, a top open cylindrical bin significantly reduces a fragmentation effect resulted from a detonation of an explosive device placed inside the bin. However, reduction of blast wave overpressure and impulse by such cylindrical bins is not sufficient [1]. A reasonable alternative to endless increase of height and thickness of robust blast inhibiting bins is a development of destructible inhibitors having no solid elements in their structure and, therefore, excluding secondary fragmentation. So, the family of "Fountain" inhibitors [2,3] localizes and suppresses damaging blast effects due to multiphase working system. The present study is analyzing data obtained in testing of prototypes of new combined inhibitors. Their structure combines robust elements (bottoms, side surfaces) with elements responsible for blast loads reduction due to multi-phase working system (top and low transverse embeddings) and fairings impeding wave propagation in undesirable directions.

  6. Device for Underwater Laboratory Simulation of Unconfined Blast Waves

    CERN Document Server

    Courtney, Elijah; Courtney, Michael

    2015-01-01

    Shock tubes simulate blast waves to study their effects in air under laboratory conditions; however, few experimental models exist for simulating underwater blast waves that are needed for facilitating experiments in underwater blast transmission, determining injury thresholds in marine animals, validating numerical models, and exploring mitigation strategies for explosive well removals. This method incorporates an oxy-acetylene driven underwater blast simulator which creates peak blast pressures of about 1860 kPa. Shot-to-shot consistency was fair, with an average standard deviation near 150 kPa. Results suggest peak blast pressures from 460 kPa to 1860 kPa are available by adjusting the distance from the source.

  7. Application of Carbon Composite Bricks for Blast Furnace Hearth

    Science.gov (United States)

    Zuo, Haibin; Wang, Cong; Zhang, Jianliang; Zhao, Yongan; Jiao, Kexin

    Traditional refractory materials for blast furnace hearth lining are mainly composed of carbon bricks and the ceramic cup. However, these materials can't meet the demands for long service life design of blast furnaces. In this paper, a new refractory called carbon composite brick (CCB) was introduced, which combined the advantages of carbon bricks and the ceramic cup. In this case, the resistance of the CCB against corrosion was equal to the ceramic cup and the thermal conductivity of the CCB was equal to carbon bricks. From the results of more than 20 blast furnaces, the CCB could be well used in small blast furnaces and large blast furnaces. In the bad condition of low grade burden and high smelting intensity, the CCB gave full play to the role of cooling system, and effectively resisted the erosion of hot metal to improve the service life of blast furnaces.

  8. Oil injection into the blast furnace

    Energy Technology Data Exchange (ETDEWEB)

    Dongsheng Liao; Mannila, P.; Haerkki, J.

    1997-12-31

    Fuel injection techniques have been extensively used in the commercial blast furnaces, a number of publications concerning the fuels injection have been reported. This present report only summarizes the study achievements of oil injection due to the research need the of authors, it includes the following parts: First, the background and the reasons reducing coke rate of oil injection are analyzed. Reducing coke rate and decreasing the ironmaking costs are the main deriving forces, the contents of C, H and ash are direct reasons reducing coke rate. It was also found that oil injection had great effects on the state of blast furnace, it made operation stable, center gas flow develop fully, pressure drop increase, descent speed of burden materials decrease and generation of thermal stagnation phenomena, the quality of iron was improved. Based on these effects, as an ideal mean, oil injection was often used to adjust the state of blast furnace. Secondly, combustion behavior of oil in the raceway and tuyere are discussed. The distribution of gas content was greatly changed, the location of CO, H{sub 2} generation was near the tuyere; the temperature peak shifts from near the raceway boundary to the tuyere. Oxygen concentration and blast velocity were two important factors, it was found that increasing excess oxygen ratio 0.9 to 1.3, the combustion time of oil decreases 0.5 msec, an increase of the blast velocity results in increasing the flame length. In addition, the nozzle position and oil rate had large effects on the combustion of oil. Based on these results, the limit of oil injection is also discussed, soot formation is the main reason limiting to further increase oil injection rate, it was viewed that there were three types of soot which were generated under blast furnace operating conditions. The reason generating soot is the incomplete conversion of the fuel. Finally, three methods improving combustion of oil in the raceway are given: Improvement of oil

  9. Development of heat-transfer circuits in the blast furnace

    Science.gov (United States)

    Spirin, N. A.; Yaroshenko, Yu G.; Lavrov, V. V.

    2016-09-01

    The development of heat-transfer circuits in the blast furnace as the technologies of blast-furnace smelting are improved are considered. It is shown that there are two zones of intense heat-transfer, and in modern conditions, when different kinds of iron ore are smelted, the use of combined blast with high parameters is a prerequisite for the stability of blastfurnace smelting operation and the smelting efficiency.

  10. Practical aspects of drilling and blasting in NCL

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, T.; Rai, V.K.; Choubey, S.N. [ICI India Limited (India)

    2000-05-01

    Drilling and blasting play a vital role in mining of Northern Coalfields Ltd.'s large opencast mines in India. The article deals with the practical aspects of drilling and blasting and discusses the company's strategy adopted in different projects to ensure accurate, safe and efficient drilling to achieve good blast for high productivity of excavating equipment. 3 figs., 1 tab.

  11. Water-Depth-Based Prediction Formula for the Blasting Vibration Velocity of Lighthouse Caused by Underwater Drilling Blasting

    Directory of Open Access Journals (Sweden)

    Wenbin Gu

    2017-01-01

    Full Text Available Lighthouses are the most important hydraulic structures that should be protected during underwater drilling blasting. Thus, the effect of blasting vibration on lighthouse should be studied. On the basis of the dimensional analysis, we deduced a revised formula for water depth based on Sodev’s empirical formula and established the linear fitting model. During the underwater reef project in the main channel of Shipu Harbor in the Ningbo–Zhoushan Port, the blasting vibration data of the lighthouse near the underwater blasting area were monitored. The undetermined coefficient, resolvable coefficient, and F value of the two formulas were then obtained. The comparison of the data obtained from the two formulas showed that they can effectively predict the blasting vibration on the lighthouse. The correction formula that considers water depth can obviously reduce prediction errors and accurately predict blasting vibration.

  12. Design and Analysis of Single Plate Blast Resistant Door

    Directory of Open Access Journals (Sweden)

    Nilesh S. Aitavade

    2013-06-01

    Full Text Available Blast Resistant Doors are used to withstand high intensity impulsive blast loads. They are designed to prevent the impact of the blast from travelling from one side to the other side of the door. Taking into account the limitations and the growing need of efficient blast resistant doors, a design was developed using ASTM A36 as the material of construction instead of concrete. Analytical calculations for the actual pressure-impulse loading condition were done as per the UFC 3-340-02, and the results of analytical calculations were compared with results of the simulation of the numerical model for the given boundary conditions.

  13. Assessment of Blasting Operations Effects During Highway Tunnel Construction

    Directory of Open Access Journals (Sweden)

    Valašková Veronika

    2015-12-01

    Full Text Available Blasting operations are one of the fundamental parts of daily civil engineering. Drilling and blasting still remain the only possible ways of tunnelling in very adverse geological conditions. However, this method is a source of various disadvantages, the main one being tremors propagating through the geological environment which not only affect buildings, but also disturb the comfort of living in the vicinity of the source. Designing this procedure is mostly done using standardized empirical relations. This article shows the possibility of using a FEM technique in predicting blast effects. This approach is demonstrated in a simple case study on the impact of blasting operations on steel pipes.

  14. Mechanisms of hearing loss after blast injury to the ear.

    Directory of Open Access Journals (Sweden)

    Sung-Il Cho

    Full Text Available Given the frequent use of improvised explosive devices (IEDs around the world, the study of traumatic blast injuries is of increasing interest. The ear is the most common organ affected by blast injury because it is the body's most sensitive pressure transducer. We fabricated a blast chamber to re-create blast profiles similar to that of IEDs and used it to develop a reproducible mouse model to study blast-induced hearing loss. The tympanic membrane was perforated in all mice after blast exposure and found to heal spontaneously. Micro-computed tomography demonstrated no evidence for middle ear or otic capsule injuries; however, the healed tympanic membrane was thickened. Auditory brainstem response and distortion product otoacoustic emission threshold shifts were found to be correlated with blast intensity. As well, these threshold shifts were larger than those found in control mice that underwent surgical perforation of their tympanic membranes, indicating cochlear trauma. Histological studies one week and three months after the blast demonstrated no disruption or damage to the intra-cochlear membranes. However, there was loss of outer hair cells (OHCs within the basal turn of the cochlea and decreased spiral ganglion neurons (SGNs and afferent nerve synapses. Using our mouse model that recapitulates human IED exposure, our results identify that the mechanisms underlying blast-induced hearing loss does not include gross membranous rupture as is commonly believed. Instead, there is both OHC and SGN loss that produce auditory dysfunction.

  15. Study on orientation fracture blasting with shaped charge in rock

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    On the basis of the theories of mechanics of explosive and rock fracture mechanics, the mechanism of crack initiation and its expansion of directional fracture controlled blasting with shaped charges in rock were studied, then the blasting parameters were designed and tested by a model test in laboratory and field experiment. The experimental and test results showed that the energy from blasting is directionally concentrated for the cumulative action. The directional expansion of cracks is satisfactory, the results of the model test and field test suggested that the orientation fracture blasting with shaped charge is a good means of excavating tunnels or cutting rock.

  16. Atmospheric electricity

    CERN Document Server

    Chalmers, J Alan

    1957-01-01

    Atmospheric Electricity brings together numerous studies on various aspects of atmospheric electricity. This book is composed of 13 chapters that cover the main problems in the field, including the maintenance of the negative charge on the earth and the origin of the charges in thunderstorms. After a brief overview of the historical developments of atmospheric electricity, this book goes on dealing with the general principles, results, methods, and the MKS system of the field. The succeeding chapters are devoted to some aspects of electricity in the atmosphere, such as the occurrence and d

  17. Electrical stator

    Science.gov (United States)

    Fanning, Alan W.; Olich, Eugene E.

    1994-01-01

    An electrical stator of an electromagnetic pump includes first and second spaced apart coils each having input and output terminals for carrying electrical current. An elongate electrical connector extends between the first and second coils and has first and second opposite ends. The connector ends include respective slots receiving therein respective ones of the coil terminals to define respective first and second joints. Each of the joints includes a braze filler fixedly joining the connector ends to the respective coil terminals for carrying electrical current therethrough.

  18. Mitigation of blast loadings on structures by an anti-blast plastic water wall

    Institute of Scientific and Technical Information of China (English)

    张力; 陈力; 方秦; 张亚栋

    2016-01-01

    Seven in-situ tests were carried out in far field to study the blast mitigation effect of a kind of water filled plastic wall. Test results show that the mitigation effect of water filled plastic wall is remarkable. The maximum reduction of peak reflected overpressure reaches up to 94.53%, as well as 36.3% of the minimum peak reflected overpressure reduction in the scaled distance ranging from 1.71 m/kg1/3 to 3.42 m/kg1/3. Parametric studies were also carried out. The effects of the scaled gauge height, water/charge scaled distance (the distance between the explosive charge and the water wall), water wall scaled height and water/structure scaled distance (the distance between the water wall and the structure) were systematically investigated and compared with the usual rigid anti-blast wall. It is concluded that these parameters affect the mitigation effects of plastic water wall on blast loadings significantly, which is basically consistent to the trend of usual rigid anti-blast wall. Some formulae are also derived based on the numerical and test results, providing a simple but reliable prediction model to evaluate the peak overpressure of mitigated blast loadings on the structures.

  19. Electro- or Turbo-Driven?—Analysis of Different Blast Processes of Blast Furnace

    Directory of Open Access Journals (Sweden)

    Wenqiang Sun

    2016-08-01

    Full Text Available There has always been a dispute about the energy efficiency and energy cost of electro-driven and turbo-driven blast furnace (BF blast processes. In order to find where the problem lies, energy efficiency analysis models and energy cost analysis models of electro-driven and turbo-driven blast processes were established, and the differences between the two driving processes in terms of theoretical minimum steam consumption, energy efficiency and energy cost were studied. The results showed that the theoretical minimum steam consumption of a blast process depends on steam thermodynamic properties and is unrelated to drive mode and drive process. A certain overlapped interval between electro-driven and turbo-driven blast processes in terms of energy efficiency exists. The equation for calculating the standard coal coefficient of steam was proposed, and the relationship to judge strengths and weaknesses of the two driving modes in terms of energy efficiency and energy cost was established. Finally, two companies were selected for case study research. The results led to different conclusions because of the differences between energy media in terms of standard coal coefficient and unit price. To select the best driving mode, plant-running conditions and energy prices of the region of operation in addition to other relevant factors should all be taken into account.

  20. Airport Ground Staff Scheduling

    DEFF Research Database (Denmark)

    Clausen, Tommy

    travels safely and efficiently through the airport. When an aircraft lands, a significant number of tasks must be performed by different groups of ground crew, such as fueling, baggage handling and cleaning. These tasks must be complete before the aircraft is able to depart, as well as check......-in and security services. These tasks are collectively known as ground handling, and are the major source of activity with airports. The business environments of modern airports are becoming increasingly competitive, as both airports themselves and their ground handling operations are changing to private...... ownership. As airports are in competition to attract airline routes, efficient and reliable ground handling operations are imperative for the viability and continued growth of both airports and airlines. The increasing liberalization of the ground handling market prompts ground handling operators...

  1. [Introduction to grounded theory].

    Science.gov (United States)

    Wang, Shou-Yu; Windsor, Carol; Yates, Patsy

    2012-02-01

    Grounded theory, first developed by Glaser and Strauss in the 1960s, was introduced into nursing education as a distinct research methodology in the 1970s. The theory is grounded in a critique of the dominant contemporary approach to social inquiry, which imposed "enduring" theoretical propositions onto study data. Rather than starting from a set theoretical framework, grounded theory relies on researchers distinguishing meaningful constructs from generated data and then identifying an appropriate theory. Grounded theory is thus particularly useful in investigating complex issues and behaviours not previously addressed and concepts and relationships in particular populations or places that are still undeveloped or weakly connected. Grounded theory data analysis processes include open, axial and selective coding levels. The purpose of this article was to explore the grounded theory research process and provide an initial understanding of this methodology.

  2. Electric machine

    Science.gov (United States)

    El-Refaie, Ayman Mohamed Fawzi [Niskayuna, NY; Reddy, Patel Bhageerath [Madison, WI

    2012-07-17

    An interior permanent magnet electric machine is disclosed. The interior permanent magnet electric machine comprises a rotor comprising a plurality of radially placed magnets each having a proximal end and a distal end, wherein each magnet comprises a plurality of magnetic segments and at least one magnetic segment towards the distal end comprises a high resistivity magnetic material.

  3. 30 CFR 817.66 - Use of explosives: Blasting signs, warnings, and access control.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Use of explosives: Blasting signs, warnings... STANDARDS-UNDERGROUND MINING ACTIVITIES § 817.66 Use of explosives: Blasting signs, warnings, and access control. (a) Blasting signs. Blasting signs shall meet the specifications of § 817.11. The operator...

  4. 30 CFR 57.22601 - Blasting from the surface (I-A mines).

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Blasting from the surface (I-A mines). 57.22601... Standards for Methane in Metal and Nonmetal Mines Explosives § 57.22601 Blasting from the surface (I-A mines... blast area and through at least one atmospheric monitoring sensor. (b) After blasting, if the...

  5. 77 FR 58173 - Proposed Extension of Existing Information Collection; Explosive Materials and Blasting Units...

    Science.gov (United States)

    2012-09-19

    ... Materials and Blasting Units (Pertains to Metal and Nonmetal Underground Mines Deemed To Be Gassy AGENCY... materials and blasting units as permissible for use in the mining industry. However, since there are no permissible explosives or blasting units available that have adequate blasting capacity for some metal...

  6. 30 CFR 816.66 - Use of explosives: Blasting signs, warnings, and access control.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Use of explosives: Blasting signs, warnings... STANDARDS-SURFACE MINING ACTIVITIES § 816.66 Use of explosives: Blasting signs, warnings, and access control. (a) Blasting signs. Blasting signs shall meet the specifications of § 816.11. The operator shall—...

  7. The ATLAS SCT grounding and shielding concept and implementation

    CERN Document Server

    Bates, RL; Bernabeu, J; Bizzell, J; Bohm, J; Brenner, R; Bruckman de Renstrom, P A; Catinaccio, A; Cindro, V; Ciocio, A; Civera, J V; Chouridou, S; Dervan, P; Dick, B; Dolezal, Z; Eklund, L; Feld, L; Ferrere, D; Gadomski, S; Gonzalez, F; Gornicki, E; Greenhall, A; Grillo, A A; Grosse-Knetter, J; Gruwe, M; Haywood, S; Hessey, N P; Ikegami, Y; Jones, T J; Kaplon, J; Kodys, P; Kohriki, T; Kondo, T; Koperny, S; Lacasta, C; Lozano Bahilo, J; Malecki, P; Martinez-McKinney, F; McMahon, S J; McPherson, A; Mikulec, B; Mikus, M; Moorhead, G F; Morrissey, M C; Nagai, K; Nichols, A; O'Shea, V; Pater, J R; Peeters, S J M; Pernegger, H; Perrin, E; Phillips, P W; Pieron, J P; Roe, S; Sanchez, J; Spencer, E; Stastny, J; Tarrant, J; Terada, S; Tyndel, M; Unno, Y; Wallny, R; Weber, M; Weidberg, A R; Wells, P S; Werneke, P; Wilmut, I

    2012-01-01

    This paper describes the design and implementation of the grounding and shielding system for the ATLAS SemiConductor Tracker (SCT). The mitigation of electromagnetic interference and noise pickup through power lines is the critical design goal as they have the potential to jeopardize the electrical performance. We accomplish this by adhering to the ATLAS grounding rules, by avoiding ground loops and isolating the different subdetectors. Noise sources are identified and design rules to protect the SCT against them are described. A rigorous implementation of the design was crucial to achieve the required performance. This paper highlights the location, connection and assembly of the different components that affect the grounding and shielding system: cables, filters, cooling pipes, shielding enclosure, power supplies and others. Special care is taken with the electrical properties of materials and joints. The monitoring of the grounding system during the installation period is also discussed. Finally, after con...

  8. Electric power systems

    CERN Document Server

    Weedy, B M; Jenkins, N; Ekanayake, J B; Strbac, G

    2012-01-01

    The definitive textbook for Power Systems students, providing a grounding in essential power system theory while also focusing on practical power engineering applications. Electric Power Systems has been an essential book in power systems engineering for over thirty years. Bringing the content firmly up-to-date whilst still retaining the flavour of Weedy's extremely popular original, this Fifth Edition has been revised by experts Nick Jenkins, Janaka Ekanayake and Goran Strbac. This wide-ranging text still covers all of the fundamental power systems subjects but is now e

  9. Ground Vehicle Robotics

    Science.gov (United States)

    2013-08-20

    Ground Vehicle Robotics Jim Parker Associate Director, Ground Vehicle Robotics UNCLASSIFIED: Distribution Statement A. Approved for public...DATE 20 AUG 2013 2. REPORT TYPE Briefing Charts 3. DATES COVERED 09-05-2013 to 15-08-2013 4. TITLE AND SUBTITLE Ground Vehicle Robotics 5a...Willing to take Risk on technology -User Evaluated -Contested Environments -Operational Data Applied Robotics for Installation & Base Ops -Low Risk

  10. The Grounded Theory Bookshelf

    Directory of Open Access Journals (Sweden)

    Vivian B. Martin, Ph.D.

    2005-03-01

    Full Text Available Bookshelf will provide critical reviews and perspectives on books on theory and methodology of interest to grounded theory. This issue includes a review of Heaton’s Reworking Qualitative Data, of special interest for some of its references to grounded theory as a secondary analysis tool; and Goulding’s Grounded Theory: A practical guide for management, business, and market researchers, a book that attempts to explicate the method and presents a grounded theory study that falls a little short of the mark of a fully elaborated theory.Reworking Qualitative Data, Janet Heaton (Sage, 2004. Paperback, 176 pages, $29.95. Hardcover also available.

  11. Electric fields and electrical insulation

    DEFF Research Database (Denmark)

    McAllister, Iain Wilson

    2002-01-01

    The adoption of a field-theoretical approach to problems arising in the framework of electrical insulation is discussed with reference to six main topics, which have been addressed over the last 30 years. These include uniform field electrodes, Green's differential equation, electrode surface......, it is amply demonstrated that such an approach can lead to significant progress in many areas of electrical insulation....

  12. Thermodynamic modeling of lead blast furnace

    Institute of Scientific and Technical Information of China (English)

    TAN Peng-fu

    2005-01-01

    A thermodynamic model was developed to predict the distribution behavior of Cu,Fe,S,O,Pb,Zn,As,and the heat balance in a lead blast furnace.The modeling results are validated by the plant data of a lead smelter in Kazakhstan.The model can be used to predict any set of controllable process parameters such as feed composition,smelting temperature,degree of oxygen enrichment and volume of oxygen-enriched air.The effects of the blast air,industrial oxygen,and coke charge on the distribution of Cu,Fe,S,O,Pb,Zn,As,the heat balance,and the lead loss in slag,were presented and discussed.

  13. Simulation of blast-induced, early-time intracranial wave physics leading to traumatic brain injury.

    Energy Technology Data Exchange (ETDEWEB)

    Taylor, Paul Allen; Ford, Corey C. (University of New Mexico, Albuquerque, NM)

    2008-04-01

    U.S. soldiers are surviving blast and impacts due to effective body armor, trauma evacuation and care. Blast injuries are the leading cause of traumatic brain injury (TBI) in military personnel returning from combat. Understanding of Primary Blast Injury may be needed to develop better means of blast mitigation strategies. The objective of this paper is to investigate the effects of blast direction and strength on the resulting mechanical stress and wave energy distributions generated in the brain.

  14. Control of City Shallow Buried Tunnel Blasting Hazard to Surface Buildings

    Directory of Open Access Journals (Sweden)

    Yang Deqiang

    2015-01-01

    Full Text Available Combining with the blasting test of an under-construction tunnel, this paper optimizes the overall blasting construction scheme. The optimized blasting scheme is used in the site construction test and the peak particle vibration velocity is strictly controlled under working conditions through blasting vibration monitoring to ensure the safety of surrounding buildings and structures in the construction process. The corresponding control measures are proposed to reduce the blasting vibration which brings certain guiding significance to the following construction project.

  15. Histologic and biomechanical evaluation of alumina-blasted/acid-etched and resorbable blasting media surfaces.

    Science.gov (United States)

    Bonfante, Estevam A; Marin, Charles; Granato, Rodrigo; Suzuki, Marcelo; Hjerppe, Jenni; Witek, Lukasz; Coelho, Paulo G

    2012-10-01

    This study evaluated the early biomechanical fixation and bone-to-implant contact (BIC) of an alumina-blasted/acid-etched (AB/AE) compared with an experimental resorbable blasting media (RBM) surface in a canine model. Higher texturization was observed for the RBM than for the AB/AE surface, and the presence of calcium and phosphorus was only observed for the RBM surface. Time in vivo and implant surface did not influence torque. For both surfaces, BIC significantly increased from 2 to 4 weeks.

  16. Structural Analysis Of Offshore Structures Exposed To Blast Loads

    DEFF Research Database (Denmark)

    Hansen, Hans Jakup; Thygesen, Ulf; Kristensen, Anders;

    2002-01-01

    Numerical methods for simulations of blast loads and resulting structural response are investigated and compared to results obtained from tests. The CFD code EXSIM is used for the simulation of the blast load. This code provides a load profile wich is entered in the FEM analysis model....

  17. Dry ice blasting for the conservation cleaning of metals

    NARCIS (Netherlands)

    van der Molen, R.; Joosten, I.; Beentjes, T.; Megens, L.; Mardikian, P.; Chemello, C.; Watters, C.; Hull, P.

    2011-01-01

    This research was carried out to assess the feasibility of dry ice blasting as a replacement for solvent cleaning for the removal of organic layers from metal cultural heritage objects. The effects of dry ice blasting on test samples of aluminium, bronze and weathering steel were studied along with

  18. The composition of the products from flameless blasting

    Energy Technology Data Exchange (ETDEWEB)

    Chikunov, V.I.; Chikunova, G.V.; Domanov, V.P.; Nezyrova, L.P.

    1979-01-01

    Results are given from research on the composition of the products resulting from Hydrox coal blasting together with a mechanism for the conversion of the components during the reaction process. Methods for decreasing the quantity of toxic gases during blasting in the stopes of coal mines that have dangerous gas and dust levels are recommended.

  19. Reduction Mechanism of Chromite Ore in Blast Furnace

    Institute of Scientific and Technical Information of China (English)

    LI Yi-wei; DING Wei-zhong; LU Xiong-gang; XU Kuang-di

    2004-01-01

    The structural changes and reduction degree of chromite ore in blast furnace were studied by optical micrograph analysis, scanning electron microscope (SEM) and energy dispersive X-ray analysis (EDXA). The smelting reduction mechanism of chromite in blast furnace was primarily discussed.

  20. Dry ice blasting for the conservation cleaning of metals

    NARCIS (Netherlands)

    van der Molen, R.; Joosten, I.; Beentjes, T.; Megens, L.; Mardikian, P.; Chemello, C.; Watters, C.; Hull, P.

    2011-01-01

    This research was carried out to assess the feasibility of dry ice blasting as a replacement for solvent cleaning for the removal of organic layers from metal cultural heritage objects. The effects of dry ice blasting on test samples of aluminium, bronze and weathering steel were studied along with

  1. Blast Loading Experiments of Surrogate Models for Tbi Scenarios

    Science.gov (United States)

    Alley, M. D.; Son, S. F.

    2009-12-01

    This study aims to characterize the interaction of explosive blast waves through simulated anatomical models. We have developed physical models and a systematic approach for testing traumatic brain injury (TBI) mechanisms and occurrences. A simplified series of models consisting of spherical PMMA shells housing synthetic gelatins as brain simulants have been utilized. A series of experiments was conducted to compare the sensitivity of the system response to mechanical properties of the simulants under high strain-rate explosive blasts. Small explosive charges were directed at the models to produce a realistic blast wave in a scaled laboratory test cell setting. Blast profiles were measured and analyzed to compare system response severity. High-speed shadowgraph imaging captured blast wave interaction with the head model while particle tracking captured internal response for displacement and strain correlation. The results suggest amplification of shock waves inside the head near material interfaces due to impedance mismatches. In addition, significant relative displacement was observed between the interacting materials suggesting large strain values of nearly 5%. Further quantitative results were obtained through shadowgraph imaging of the blasts confirming a separation of time scales between blast interaction and bulk movement. These results lead to the conclusion that primary blast effects could cause TBI occurrences.

  2. Methodology of Testing Shot Blasting Machines in Industrial Conditions

    Directory of Open Access Journals (Sweden)

    R. Wrona

    2012-04-01

    Full Text Available Shot blasting machines are widely used for automated surface treatment and finishing of castings. In shot blasting processes the stream of shots is generated and shaped by blasting turbines, making up a kinetic and dynamic system comprising a separating rotor, an adapting sleeve and a propelling rotor provided with blades. The shot blasting performance- i.e. the quality of shot treated surfaces depends on the actual design and operational parameters of the unit whilst the values of relevant parameters are associated with the geometry of turbine components and the level of its integration with the separator system. The circulation of the blasting medium becomes the integrating factor of the process line, starting from the hopper, through the propeller turbine, casting treatment, separation of contaminated abrasive mixture, to its recycling and reuse.Inferior quality of the abrasive agent (shot and insufficient purity of the abrasive mixture are responsible for low effectiveness of shot blasting. However, most practitioners fail to fully recognise the importance of proper diagnostics of the shot blasting process in industrial conditions. The wearing of major machine components and of the blasting agent and quality of shot treated surfaces are often misinterpreted, hence the need to take into account all factors involved in the process within the frame of a comprehensive methodology.This paper is an attempt to formulate and apply the available testing methods to the engineering practice in industrial conditions.

  3. Dry ice blasting for the conservation cleaning of metals

    NARCIS (Netherlands)

    R. van der Molen; I. Joosten; T. Beentjes; L. Megens

    2010-01-01

    This research was carried out to assess the feasibility of dry ice blasting as a replacement for solvent cleaning for the removal of organic layers from metal cultural heritage objects. The effects of dry ice blasting on test samples of aluminium, bronze and weathering steel were studied along with

  4. New technique for identifying varieties resistance to rice blast

    Institute of Scientific and Technical Information of China (English)

    ZHUPeiliang

    1994-01-01

    After 8 yrs lab experiments and field tests, an advanced technique for identifying varieties resistance to rice blast was developed by a research group in Plant Protection Institute, Zhejiang Academy of AgricuLltural Sciences. With this technique, the inoculum was prepared on a maizc-rice-straw-agar media which was suitable for sporulation of most rice blast pathogen isolates.

  5. Blast event simulation for a vehicle subjected to an explosion

    NARCIS (Netherlands)

    Zhang, G.; Vlahopoulos, N.; Goetz, R.; Velde, R. van de

    2007-01-01

    One of the main threats to military vehicles originates from blasts. In order to improve the survivability of the occupants it is important to design a military vehicle for increased occupant safety. Simulation technology that combines modeling of the blast loads from an explosion, the response of t

  6. Preliminary blasting as a means of constructing the final slopes

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Jimeno, E.; Lopez Jimeno, C. (Lignitos de Meirama, La Coruna (Spain))

    1983-01-01

    In order to undertake construction of a new belt at the Meirama opencast lignite workings in the Province of Coruna it has been necessary partially to re-site the slope of the general haulage drift. Preliminary blasting was thought to be the most suitable method of blasting in order to maintain slope stability of the rock mass. (17 refs.)

  7. In Vitro Studies of Primary Explosive Blast Loading on Neurons

    Science.gov (United States)

    2015-09-01

    ARL-RP-0542 ● SEP 2015 US Army Research Laboratory In Vitro Studies of Primary Explosive Blast Loading on Neurons by Nicole E Zander, Thuvan...Research Laboratory In Vitro Studies of Primary Explosive Blast Loading on Neurons by Nicole E Zander, Thuvan Piehler, Rohan Banton, and Richard...

  8. Prevention of Blast-Related Injuries

    Science.gov (United States)

    2014-07-01

    curvature changes. Figure 38. Locations with element disconnect issues 2. Modeling air blast wave propagation using a 2-D to 3-D mapping...sagittal sinus, transverse sinus, cerebral spinal fluid (CSF), hemispheres of the cerebrum with distinct white and gray matter, cerebellum, brainstem...brain and cerebral spinal fluid (CSF) were meshed and defined with Lagrangian formulation-based elements. The CSF fills the subarachnoid space

  9. Blast Injuries: What Clinicians Need to Know

    Centers for Disease Control (CDC) Podcasts

    2008-11-05

    In this podcast, Dr. Richard C. Hunt, Director of the CDC’s Division of Injury Response, National Center for Injury Prevention and Control provides a brief overview for health care providers on how to respond and care for persons injured by an explosion or blast event.  Created: 11/5/2008 by National Center for Injury Prevention and Control (NCIPC), Division of Injury Response (DIR).   Date Released: 11/6/2008.

  10. Structural Optimization for Blast Mitigation Using HCA

    Science.gov (United States)

    2009-08-14

    UNCLASSIFIED
 Structural Optimization for Blast Mitigation Using HCA University of Notre Dame John Goetz, Huade Tan, Andrés Tovar , John Renaud...John Goetz; Huande Tan; Andres Tovar ; John Renaud 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND...Overview: Algorithm •  A continuum-based topology optimization –  First utilized for bone remodeling ( Tovar ’04) –  Extend bone remodeling technique for

  11. Response Mechanism: Blast/Fire Interactions.

    Science.gov (United States)

    1983-11-01

    present research. The problem of blast interaction with fire was studied theoretically by Fendell at TRW [6) and experimentally by Martin, Backovsky and...Editors, SRI International Report for DCPA, Contract No. DCPA01-78-C-0279, Work Unit 2563F (September 1979). 6. Carrier, G., Fendell , F., Feldman P...Engineering University of California Gainesville, FL 32601 P.O. Box 808, L-140 Livermore, CA 94550 Dr. Francis E. Fendell R1/1038 Mr. Edward L. Hill TRW

  12. Simulation of Blast on Porcine Head

    Science.gov (United States)

    2015-07-01

    S55–S61. Covey DC, Born CT. Blast injuries: mechanics and wounding patterns. J Surgical Orthopaedic Advances. 2010;19(1):8–12. Culbert RW. The vapor...Powell BJ, Baumer TG, Passalacqua NV, Wagner CD, Haut RC, Fenton TW, Yang KH. A forensic pathology tool to predict pediatric skull fracture patterns...microstructural and cerebrovascular changes during normal swine brain development. Pediatric Research, 2011;69(5):418– 424. Winter J. The material properties

  13. Seamounts, Direct Blast and Volume Reverberation Upgrades

    Science.gov (United States)

    1988-11-30

    Highway. Suits 1204. Arlington, VA 22202-4302. "n to the Office of Management and Budget. Peperworik Reduction Project (0704-0188). Washington. DC 2050M. 1...Subtitle. 5. Funding Numbers. Seamounts, Direct Blast And Volume Reverberation Upgrades proram Eemen No 3 7 85N Project No R02017 6. Author(s). L...Section Pae 1 INTRODUCTION ................................. 1-1 2 ASERT: DATA PREPARATION FOR ASTRAL ........... 2-1 2.1 Overview and Purpose of

  14. Centrifugal shot blasting. Innovative technology summary report

    Energy Technology Data Exchange (ETDEWEB)

    1999-07-01

    At the US Department of Energy (DOE) Fernald Environmental Management Project (FEMP), the Facilities Closure and Demolition Projects Integrated Remedial Design/Remedial Action (RD/RA) work plan calls for the removal of one inch (1 in) depth of concrete surface in areas where contamination with technetium-99 has been identified. This report describes a comparative demonstration between two concrete removal technologies: an innovative system using Centrifugal Shot Blasting (CSB) and a modified baseline technology called a rotary drum planer.

  15. Pesticides in Ground Water

    DEFF Research Database (Denmark)

    Bjerg, Poul Løgstrup

    1996-01-01

    Review af: Jack E. Barbash & Elizabeth A. Resek (1996). Pesticides in Ground Water. Distribution trends and governing factors. Ann Arbor Press, Inc. Chelsea, Michigan. pp 588.......Review af: Jack E. Barbash & Elizabeth A. Resek (1996). Pesticides in Ground Water. Distribution trends and governing factors. Ann Arbor Press, Inc. Chelsea, Michigan. pp 588....

  16. Pesticides in Ground Water

    DEFF Research Database (Denmark)

    Bjerg, Poul Løgstrup

    1996-01-01

    Review af: Jack E. Barbash & Elizabeth A. Resek (1996). Pesticides in Ground Water. Distribution trends and governing factors. Ann Arbor Press, Inc. Chelsea, Michigan. pp 588.......Review af: Jack E. Barbash & Elizabeth A. Resek (1996). Pesticides in Ground Water. Distribution trends and governing factors. Ann Arbor Press, Inc. Chelsea, Michigan. pp 588....

  17. Communication, concepts and grounding.

    Science.gov (United States)

    van der Velde, Frank

    2015-02-01

    This article discusses the relation between communication and conceptual grounding. In the brain, neurons, circuits and brain areas are involved in the representation of a concept, grounding it in perception and action. In terms of grounding we can distinguish between communication within the brain and communication between humans or between humans and machines. In the first form of communication, a concept is activated by sensory input. Due to grounding, the information provided by this communication is not just determined by the sensory input but also by the outgoing connection structure of the conceptual representation, which is based on previous experiences and actions. The second form of communication, that between humans or between humans and machines, is influenced by the first form. In particular, a more successful interpersonal communication might require forms of situated cognition and interaction in which the entire representations of grounded concepts are involved.

  18. Stochastic ground motion simulation

    Science.gov (United States)

    Rezaeian, Sanaz; Xiaodan, Sun; Beer, Michael; Kougioumtzoglou, Ioannis A.; Patelli, Edoardo; Siu-Kui Au, Ivan

    2014-01-01

    Strong earthquake ground motion records are fundamental in engineering applications. Ground motion time series are used in response-history dynamic analysis of structural or geotechnical systems. In such analysis, the validity of predicted responses depends on the validity of the input excitations. Ground motion records are also used to develop ground motion prediction equations(GMPEs) for intensity measures such as spectral accelerations that are used in response-spectrum dynamic analysis. Despite the thousands of available strong ground motion records, there remains a shortage of records for large-magnitude earthquakes at short distances or in specific regions, as well as records that sample specific combinations of source, path, and site characteristics.

  19. Ground energy coupling

    Science.gov (United States)

    Metz, P. D.

    The feasibility of ground coupling for various heat pump systems was investigated. Analytical heat flow models were developed to approximate design ground coupling devices for use in solar heat pump space conditioning systems. A digital computer program called GROCS (GRound Coupled Systems) was written to model 3-dimensional underground heat flow in order to simulate the behavior of ground coupling experiments and to provide performance predictions which have been compared to experimental results. GROCS also has been integrated with TRNSYS. Soil thermal property and ground coupling device experiments are described. Buried tanks, serpentine earth coils in various configurations, lengths and depths, and sealed vertical wells are being investigated. An earth coil used to heat a house without use of resistance heating is described.

  20. Air-Decking Technique in Bench Blasting

    Institute of Scientific and Technical Information of China (English)

    ZHU Hong-bing; LU Wen-bo; WU Liang

    2006-01-01

    The mechanism and the design parameters of blasting with air-decking are studied. The theory of detonation waves is used to investigate the processes of the one-dimensional plane detonation wave within a borehole. The interaction of the rarefaction wave with an interface and reflection on a rigid wall is also analyzed. The same courses of the shock wave are also investigated. This decides the distribution of the pressure of the explosion products changing with time along the borehole. Based on the above theoretical analysis, two conditions should be met for a reasonable range of values of the air-decking ratio in blasting rock. First, the rarefaction wave from the contact interface between detonation products and air reaches the bottom earlier than that of the reflected shock wave from the end of the stemming. Second,the reflected shock wave reaches the contact interface between the detonation products and air earlier than that of the reflected rarefaction wave from the bottom of the borehole. Finally, the reasonable value of the air-decking ratio must be decided theoretically in air-decking blasting. For different explosives, the reasonable range of air-decking ratio varies from 0.15 to 0.4. This result is well consistent with what was obtained by previous researchers.

  1. D-BLAST OFDM with Channel Estimation

    Directory of Open Access Journals (Sweden)

    Du Jianxuan

    2004-01-01

    Full Text Available Multiple-input and multiple-output (MIMO systems formed by multiple transmit and receive antennas can improve performance and increase capacity of wireless communication systems. Diagonal Bell Laboratories Layered Space-Time (D-BLAST structure offers a low-complexity solution for realizing the attractive capacity of MIMO systems. However, for broadband wireless communications, channel is frequency-selective and orthogonal frequency division multiplexing (OFDM has to be used with MIMO techniques to reduce system complexity. In this paper, we investigate D-BLAST for MIMO-OFDM systems. We develop a layerwise channel estimation algorithm which is robust to channel variation by exploiting the characteristic of the D-BLAST structure. Further improvement is made by subspace tracking to considerably reduce the error floor. Simulation results show that the layerwise estimators require 1 dB less signal-to-noise ratio (SNR than the traditional blockwise estimator for a word error rate (WER of when Doppler frequency is 40 Hz. Among the layerwise estimators, the subspace-tracking estimator provides a 0.8 dB gain for WER with 200 Hz Doppler frequency compared with the DFT-based estimator.

  2. Numerical Calculation of Concrete Slab Response to Blast Loading

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xiaoqing; HAO Hong; KUZNETSOV Valerian A; WASCHL John

    2006-01-01

    In the present paper,a dynamic plastic damage model for concrete has been employed to estimate responses of a reinforced concrete slab subjected to blast loading.The interaction between the blast wave and the concrete slab is considered in 3D simulation.In the first stage,the initial detonation and blast wave propagation is modelled in 2D simulation before the blast wave reaches the concrete slab,then the results obtained from 2D calculation are remapped to a 3D model.The calculated blast load is compared with that obtained from TM5-1300.Numerical results of the concrete slab response are compared with the explosive test carried out in the Weapons System Division,Defence Science and Technology Organisation,Department of Defence,Australia.

  3. The past and present of blast injury research in China

    Institute of Scientific and Technical Information of China (English)

    Yan Zhao; Yuan-Guo Zhou

    2015-01-01

    With the increasing incidence of blast injury,the research on its mechanisms and protective measures draws more and more attention.Blast injury has many characteristics different from general war injuries or trauma.For example,soldiers often have various degrees of visceral injury without significant surface damage,combined injuries and arterial air embolism.Researchers in China began to investigate blast injury later than the United States and Sweden,but the development is so fast that lots of achievements have been gained,including the development of biological shock tube,the mechanisms and characteristics of blast injury in various organs,as well as protective measures under special environments.This article reviews the past and current situation of blast injury research in China.

  4. Influence of maximum decking charge on intensity of blasting vibration

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Based on the character of short-time non-stationary random signal, the relationship between the maximum decking charge and energy distribution of blasting vibration signals was investigated by means of the wavelet packet method. Firstly, the characteristics of wavelet transform and wavelet packet analysis were described. Secondly, the blasting vibration signals were analyzed by wavelet packet based on software MATLAB, and the change of energy distribution curve at different frequency bands were obtained. Finally, the law of energy distribution of blasting vibration signals changing with the maximum decking charge was analyzed. The results show that with the increase of decking charge, the ratio of the energy of high frequency to total energy decreases, the dominant frequency bands of blasting vibration signals tend towards low frequency and blasting vibration does not depend on the maximum decking charge.

  5. Note: A table-top blast driven shock tube.

    Science.gov (United States)

    Courtney, Michael W; Courtney, Amy C

    2010-12-01

    The prevalence of blast-induced traumatic brain injury in conflicts in Iraq and Afghanistan has motivated laboratory scale experiments on biomedical effects of blast waves and studies of blast wave transmission properties of various materials in hopes of improving armor design to mitigate these injuries. This paper describes the design and performance of a table-top shock tube that is more convenient and widely accessible than traditional compression driven and blast driven shock tubes. The design is simple: it is an explosive driven shock tube employing a rifle primer that explodes when impacted by the firing pin. The firearm barrel acts as the shock tube, and the shock wave emerges from the muzzle. The small size of this shock tube can facilitate localized application of a blast wave to a subject, tissue, or material under test.

  6. A Table-top Blast Driven Shock Tube

    CERN Document Server

    Courtney, Michael; 10.1063/1.3518970

    2011-01-01

    The prevalence of blast-induced traumatic brain injury in conflicts in Iraq and Afghanistan has motivated laboratory scale experiments on biomedical effects of blast waves and studies of blast wave transmission properties of various materials in hopes of improving armor design to mitigate these injuries. This paper describes the design and performance of a table-top shock tube that is more convenient and widely accessible than traditional compression driven and blast driven shock tubes. The design is simple: it is an explosive driven shock tube employing a rifle primer which explodes when impacted by the firing pin. The firearm barrel acts as the shock tube, and the shock wave emerges from the muzzle. The small size of this shock tube can facilitate localized application of a blast wave to a subject, tissue, or material under test.

  7. High-speed measurement of firearm primer blast waves

    CERN Document Server

    Courtney, Michael; Eng, Jonathan; Courtney, Amy

    2012-01-01

    This article describes a method and results for direct high-speed measurements of firearm primer blast waves employing a high-speed pressure transducer located at the muzzle to record the blast pressure wave produced by primer ignition. Key findings are: 1) Most of the lead styphnate based primer models tested show 5.2-11.3% standard deviation in the magnitudes of their peak pressure. 2) In contrast, lead-free diazodinitrophenol (DDNP) based primers had standard deviations of the peak blast pressure of 8.2-25.0%. 3) Combined with smaller blast waves, these large variations in peak blast pressure of DDNP-based primers led to delayed ignition and failure to fire in brief field tests.

  8. Electrical Conductivity.

    Science.gov (United States)

    Hershey, David R.; Sand, Susan

    1993-01-01

    Explains how electrical conductivity (EC) can be used to measure ion concentration in solutions. Describes instrumentation for the measurement, temperature dependence and EC, and the EC of common substances. (PR)

  9. Electrical Injuries

    Science.gov (United States)

    ... it can pass through your body and cause injuries. These electrical injuries can be external or internal. You may have one or both types. External injuries are skin burns. Internal injuries include damage to ...

  10. Electricity derivatives

    CERN Document Server

    Aïd, René

    2015-01-01

    Offering a concise but complete survey of the common features of the microstructure of electricity markets, this book describes the state of the art in the different proposed electricity price models for pricing derivatives and in the numerical methods used to price and hedge the most prominent derivatives in electricity markets, namely power plants and swings. The mathematical content of the book has intentionally been made light in order to concentrate on the main subject matter, avoiding fastidious computations. Wherever possible, the models are illustrated by diagrams. The book should allow prospective researchers in the field of electricity derivatives to focus on the actual difficulties associated with the subject. It should also offer a brief but exhaustive overview of the latest techniques used by financial engineers in energy utilities and energy trading desks.

  11. 4' and 24' Shock Tubes - Electric Arc Shock Tube Facililty N-229 (East) The facility is used to

    Science.gov (United States)

    1978-01-01

    4' and 24' Shock Tubes - Electric Arc Shock Tube Facililty N-229 (East) The facility is used to investigate the effects of radiation and ionization during outer planetary entries as well as for air-blast simualtion which requires the strongest possible shock generation in air at loadings of 1 atm or greater.

  12. Phylogenomic analysis uncovers the evolutionary history of nutrition and infection mode in rice blast fungus and other Magnaporthales.

    Science.gov (United States)

    Luo, Jing; Qiu, Huan; Cai, Guohong; Wagner, Nicole E; Bhattacharya, Debashish; Zhang, Ning

    2015-03-30

    The order Magnaporthales (Ascomycota, Fungi) includes devastating pathogens of cereals, such as the rice blast fungus Pyricularia (Magnaporthe) oryzae, which is a model in host-pathogen interaction studies. Magnaporthales also includes saprotrophic species associated with grass roots and submerged wood. Despite its scientific and economic importance, the phylogenetic position of Magnaporthales within Sordariomycetes and the interrelationships of its constituent taxa, remain controversial. In this study, we generated novel transcriptome data from 21 taxa that represent key Magnaporthales lineages of different infection and nutrition modes and phenotypes. Phylogenomic analysis of >200 conserved genes allowed the reconstruction of a robust Sordariomycetes tree of life that placed the monophyletic group of Magnaporthales sister to Ophiostomatales. Among Magnaporthales, three major clades were recognized: 1) an early diverging clade A comprised of saprotrophs associated with submerged woods; 2) clade B that includes the rice blast fungus and other pathogens that cause blast diseases of monocot plants. These species infect the above-ground tissues of host plants using the penetration structure, appressorium; and 3) clade C comprised primarily of root-associated species that penetrate the root tissue with hyphopodia. The well-supported phylogenies provide a robust framework for elucidating evolution of pathogenesis, nutrition modes, and phenotypic characters in Magnaporthales.

  13. A joint analysis of BLAST 250--500um and LABOCA 870um observations in the Extended Chandra Deep Field South

    CERN Document Server

    Chapin, Edward L; Coppin, Kristen E; Devlin, Mark J; Dunlop, James S; Greve, Thomas R; Halpern, Mark; Hasselfied, Matthew F; Hughes, David H; Ivison, Rob J; Marsden, Gaelen; Moncelsi, Lorenzo; Netterfield, Calvin B; Pascale, Enzo; Scott, Douglas; Smail, Ian; Viero, Marco; Walter, Fabian; Weiss, Axel; van der Werf, Paul

    2010-01-01

    We present a joint analysis of the overlapping BLAST 250, 350, 500um, and LABOCA 870um observations (from the LESS survey) of the Extended Chandra Deep Field South. Out to z ~ 3, the BLAST filters sample near the peak wavelength of thermal far-infrared (FIR) emission from galaxies (rest-frame wavelengths ~ 60--200um), primarily produced by dust heated through absorption in star-forming clouds. However, identifying counterparts to individual BLAST sources is very challenging, given the large beams (FWHM 36--60 arcsec). In contrast, the ground-based 870um observations have a significantly smaller 19 arcsec FWHM beam, and are sensitive to higher-redshifts (z ~ 1--5, and potentially beyond) due to the more favourable negative K-correction. In this study we use the LESS data, as well as deep Spitzer and VLA imaging, to identify 125 individual sources that produce significant emission in the BLAST bands. We characterize the temperatures and FIR luminosities for a subset of 73 sources with well-measured submm SEDs a...

  14. Modeling of signal propagation and sensor performance for infrasound and blast noise

    Science.gov (United States)

    Glaser, Danney R.; Wilson, D. Keith; Waldrop, Lauren E.; Hart, Carl R.; White, Michael J.; Nykaza, Edward T.; Swearingen, Michelle E.

    2017-05-01

    This paper describes a comprehensive modeling approach for infrasonic (sub-audible acoustic) signals, which starts with an accurate representation of the source spectrum and directivity, propagates the signals through the environment, and senses and processes the signals at the receiver. The calculations are implemented within EASEE (Environmental Awareness for Sensor and Emitter Employment), which is a general software framework for modeling the impacts of terrain and weather on target signatures and the performance of a diverse range of battlefield sensing systems, including acoustic, seismic, RF, visible, and infrared. At each stage in the modeling process, the signals are described by realistic statistical distributions. Sensor performance is quantified using statistical metrics such as probability of detection and target location error. To extend EASEE for infrasonic calculations, new feature sets were created including standard octaves and one-third octaves. A library of gunfire and blast noise spectra and directivity functions was added from ERDC's BNOISE (Blast Noise) and SARNAM (Small Arms Range Noise Assessment Model) software. Infrasonic propagation modeling is supported by extension of several existing propagation algorithms, including a basic ground impedance model, and the Green's function parabolic equation (GFPE), which provides accurate numerical solutions for wave propagation in a refractive atmosphere. The BNOISE propagation algorithm, which is based on tables generated by a fast-field program (FFP), was also added. Finally, an extensive library of transfer functions for microphones operating in the infrasonic range were added, which interface to EASEE's sensor performance algorithms. Example calculations illustrate terrain and atmospheric impacts on infrasonic signal propagation and the directivity characteristics of blast noise.

  15. Study on smooth blasting parameter optimization of medium-length hole in hard rock inclined roadway drivage%硬岩斜巷掘进中深孔光爆参数优化研究

    Institute of Scientific and Technical Information of China (English)

    孟小瑞

    2016-01-01

    为提高硬岩斜巷成型质量和施工效率,以桃园煤矿人行上山爆破施工为背景,分析了造成炮眼利用率较低、巷道超欠挖严重及施工效率较低的原因,结合理论计算和工程前期施工经验对各爆破参数进行优化.结果表明:优化后的爆破方案采用全断面一次起爆,掏槽选用三级楔形掏槽,周边眼炮眼密集系数取0.89,底板眼呈双排梅花型布置,可使炮眼利用率提高到90.5%,巷道成型质量显著提高,每爆破循环节约用时1 h.%To improve the forming quality and construction efficiency of hard rock inclined roadway,taking the blasting construction of walkway rise in Taoyuan Coal Mine as the back-ground,the reasons for low use ratio of blast hole,serious back break of roadway and low con-struction efficiency were analyzed,and the blasting parameters was optimized by combining with theoretical calculation and previous construction experience. The results showed that the opti-mized blasting scheme with full section one-time blasting method,three-level wedge cut,inten-sive coefficient of periphery hole adopting 0.89 and double-row quincunx type distributed floor hole could increase the use ratio of blast hole to 90.5%. The roadway forming quality improved significantly and the time of each blasting cycle decreased to 1 h.

  16. Technique applied in electrical power distribution for Satellite Launch Vehicle

    Directory of Open Access Journals (Sweden)

    João Maurício Rosário

    2010-09-01

    Full Text Available The Satellite Launch Vehicle electrical network, which is currently being developed in Brazil, is sub-divided for analysis in the following parts: Service Electrical Network, Controlling Electrical Network, Safety Electrical Network and Telemetry Electrical Network. During the pre-launching and launching phases, these electrical networks are associated electrically and mechanically to the structure of the vehicle. In order to succeed in the integration of these electrical networks it is necessary to employ techniques of electrical power distribution, which are proper to Launch Vehicle systems. This work presents the most important techniques to be considered in the characterization of the electrical power supply applied to Launch Vehicle systems. Such techniques are primarily designed to allow the electrical networks, when submitted to the single-phase fault to ground, to be able of keeping the power supply to the loads.

  17. Visual Dysfunctions at Different Stages after Blast and Non-blast Mild Traumatic Brain Injury.

    Science.gov (United States)

    Capó-Aponte, José E; Jorgensen-Wagers, Kendra L; Sosa, Josue A; Walsh, David V; Goodrich, Gregory L; Temme, Leonard A; Riggs, Daniel W

    2017-01-01

    To assess the prevalence of visual dysfunctions and associated symptoms in war fighters at different stages after non-blast- or blast-induced mild traumatic brain injury (mTBI). A comprehensive retrospective review of the electronic health records of 500 U.S. military personnel with a diagnosis of deployment-related mTBI who received eye care at the Landstuhl Regional Medical Center. For analysis, the data were grouped by mechanism of injury, and each group was further divided in three subgroups based on the number of days between injury and initial eye examination. The data showed a high frequency of visual symptoms and visual dysfunctions. However, the prevalence of visual symptoms and visual dysfunctions did not differ significantly between mechanism of injury and postinjury stage, except for eye pain and diplopia. Among visual symptoms, binocular dysfunctions were more common, including higher near vertical phoria, reduced negative fusional vergence break at near, receded near point of convergence, decreased stereoacuity, and reduced positive relative accommodation. The lack of difference in terms of visual sequelae between subgroups (blast vs. nonblast) suggests that research addressing the assessment and management of mTBI visual sequelae resulting from civilian nonblast events is relevant to military personnel where combat injury results primarily from a blast event.

  18. A Blast Headform Surrogate for the Assessment of Blast-Induced Traumatic Brain Injury

    Science.gov (United States)

    2012-11-27

    Correct fit of headwear , Representative blast diffraction around headform – Biofidelic wrt internal geometry and material selection: Stress transmission...overpressure histories • With and without protective headwear BI2PED – Recent results Introduction Strategy Facilities Iterations BI2PED & results

  19. Ground State Spin Logic

    CERN Document Server

    Whitfield, J D; Biamonte, J D

    2012-01-01

    Designing and optimizing cost functions and energy landscapes is a problem encountered in many fields of science and engineering. These landscapes and cost functions can be embedded and annealed in experimentally controllable spin Hamiltonians. Using an approach based on group theory and symmetries, we examine the embedding of Boolean logic gates into the ground state subspace of such spin systems. We describe parameterized families of diagonal Hamiltonians and symmetry operations which preserve the ground state subspace encoding the truth tables of Boolean formulas. The ground state embeddings of adder circuits are used to illustrate how gates are combined and simplified using symmetry. Our work is relevant for experimental demonstrations of ground state embeddings found in both classical optimization as well as adiabatic quantum optimization.

  20. Features of energy distribution for blast vibration signals based on wavelet packet decomposition

    Institute of Scientific and Technical Information of China (English)

    LING Tong-hua; LI Xi-bing; DAI Ta-gen; PENG Zhen-bin

    2005-01-01

    Blast vibration analysis constitutes the foundation for studying the control of blasting vibration damage and provides the precondition of controlling blasting vibration. Based on the characteristics of short-time nonstationary random signal, the laws of energy distribution are investigated for blasting vibration signals in different blasting conditions by means of the wavelet packet analysis technique. The characteristics of wavelet transform and wavelet packet analysis are introduced. Then, blasting vibration signals of different blasting conditions are analysed by the wavelet packet analysis technique using MATLAB; energy distribution for different frequency bands is obtained. It is concluded that the energy distribution of blasting vibration signals varies with maximum decking charge,millisecond delay time and distances between explosion and the measuring point. The results show that the wavelet packet analysis method is an effective means for studying blasting seismic effect in its entirety, especially for constituting velocity-frequency criteria.

  1. Air blast circuit breaker noise and hearing loss: a multifactorial model for risk assessment.

    Science.gov (United States)

    McBride, D I; Williams, S

    2000-04-01

    The assessment of the risk to hearing from impulse noise exposure may be a problem for the occupational physician because existing legislative and international noise exposure standards deal primarily with continuous noise, and are not valid in excess of the peak exposure limit of 200 pa (140 dB). Noise exposure in excess of this level, for example that due to firearms, is frequently perceived as harmful, but this is not necessarily the case, as impulse noise standards do, in fact, allow exposure with a maximum in the order of 6.3 kPa (170 dB). To illustrate this, a cross-sectional group of electrical transmission workers have been studied who were exposed to significant levels of impulse noise from air blast circuit breakers and firearms. Important hearing loss factors have been identified by means of a specially designed questionnaire. Using the Health & Safety Executive definition, the risk of hearing loss was determined by calculating prevalence odds ratios (ORs) for exposure to these factors. The OR for those with fewer than eight unprotected air blast circuit breaker exposures was 2.27 (95% confidence interval (CI), 1.01-5.08), whilst for those with more than eight exposures the OR was 2.10 (95% CI, 0.97-4.54). For firearm exposure, ORs of 1.61 (95% CI, 0.95-2.74) were noted in the medium exposure group and 2.05 (95% CI, 1.08-3.86) in the high exposure group. When all the factors were included in the model, the most significant factor was age. The study gives support to the impulse noise exposure criteria, confirming the borderline risk from air blast circuit breaker noise exposure and the relative safety of moderate gunfire exposure.

  2. Effects of different blasting materials on charge generation and decay on titanium surface after sandblasting.

    Science.gov (United States)

    Guo, Cecilia Yan; Hong Tang, Alexander Tin; Hon Tsoi, James Kit; Matinlinna, Jukka Pekka

    2014-04-01

    It has been reported that sandblasting titanium with alumina (Al2O3) powder could generate a negative electric charge on titanium surface. This has been proven to promote osteoblast activities and possibly osseointegration. The purpose of this pilot study was to investigate the effects of different blasting materials, in terms of the grit sizes and electro-negativity, on the generation of a negative charge on the titanium surface. The aim was also to make use of these results to deduct the underlying mechanism of charge generation by sandblasting. Together 60 c.p. 2 titanium plates were machine-cut and polished for sandblasting, and divided into 6 groups with 10 plates in each. Every plate in the study groups was sandblasted with one of the following 6 powder materials: 110µm Al2O3 grits, 50µm Al2O3 grits, 150-300µm glass beads, 45-75µm glass beads, 250µm Al powder and 44µm Al powder. The static voltage on the surface of every titanium plate was measured immediately after sandblasting. The static voltages of the titanium plates were recorded and processed using statistical analysis. The results suggested that only sandblasting with 45-75µm glass beads generated a positive charge on titanium, while using all other blasting materials lead to a negative charge. Furthermore, blasting grits of the same powder material but of different sizes might lead to different amount and polarity of the charges. This triboelectric effect is likely to be the main mechanism for charge generation through sandblasting.

  3. Integration of the blast furnace route and the FINEX {sup registered} -Process for low CO{sub 2} hot metal production

    Energy Technology Data Exchange (ETDEWEB)

    Thaler, Christoph; Schenk, Johannes L. [Montanuniversitaet Leoben, Chair of Metallurgy, Leoben (Austria); Tappeiner, Tamara; Kepplinger, Werner L. [Montanuniversitaet Leoben, Institute of Process Engineering and Environmental Protection, Leoben (Austria); Plaul, Jan Friedemann [Siemens VAI Metals Technologies GmbH, Linz (Austria); Schuster, Stefan [Voestalpine Stahl GmbH, Linz (Austria)

    2012-02-15

    The blast furnace is the most important process for the production of hot metal. An integral part of this process route is the coking of coal and sintering of fine ore. The FINEX {sup registered} -process is a new technology for hot metal production which uses untreated fine ores and coal instead of sinter and coke. This paper deals with the investigation of integration concepts of the blast furnace and FINEX {sup registered}. Low reduced iron (LRI) and/or reducing gas are/is produced in FINEX {sup registered} and are/is considered as substitute/s of burden and fuel in the blast furnace, respectively. In the article the overall fuel demand and CO{sub 2} emissions for the integration of the blast furnace and FINEX {sup registered} are shown. For that reason two case studies for the integration are carried out and compared with the base case, that is, the two-independent processes. The CO{sub 2} emissions are calculated considering the fuel and electric power consumption of the different cases. (Copyright copyright 2012 Wiley-VCH Verlag GmbH and Co. KGaA, Weinheim)

  4. Ground Vehicle Robotics Presentation

    Science.gov (United States)

    2012-08-14

    Mr. Jim Parker Associate Director Ground Vehicle Robotics Distribution Statement A. Approved for public release Report Documentation Page...Briefing 3. DATES COVERED 01-07-2012 to 01-08-2012 4. TITLE AND SUBTITLE Ground Vehicle Robotics Presentation 5a. CONTRACT NUMBER 5b. GRANT...ABSTRACT Provide Transition-Ready, Cost-Effective, and Innovative Robotics and Control System Solutions for Manned, Optionally-Manned, and Unmanned

  5. electric vehicle

    Directory of Open Access Journals (Sweden)

    W. R. Lee

    1999-01-01

    Full Text Available A major problem facing battery-powered electric vehicles is in their batteries: weight and charge capacity. Thus, a battery-powered electric vehicle only has a short driving range. To travel for a longer distance, the batteries are required to be recharged frequently. In this paper, we construct a model for a battery-powered electric vehicle, in which driving strategy is to be obtained such that the total travelling time between two locations is minimized. The problem is formulated as an optimization problem with switching times and speed as decision variables. This is an unconventional optimization problem. However, by using the control parametrization enhancing technique (CPET, it is shown that this unconventional optimization is equivalent to a conventional optimal parameter selection problem. Numerical examples are solved using the proposed method.

  6. 交流线路与+800 kV直流线路同走廊时的地面混合电场研究%Study on the Hybrid Electric Field Over the Ground Surface Under AC Lines and ±800 kV DC Lines in the Same Corridor

    Institute of Scientific and Technical Information of China (English)

    杨勇; 陆家榆; 鞠勇

    2009-01-01

    交流线路与±800 kV直流线路共用走廊的情况将在我困出现,因此需要研究该种线路地面混合电场的计算方法,以满足工程设计和环境保护需要.在分析同走廊架设的交流线路与±800 kV直流线路相互影响的基础上,提出了一种计算该类线路地面混合电场的方法.通过对比使用该方法得到的计算结果与不考虑两种线路相互影响时的计算结果,得到如下结论:相对于忽略交直流线路的相互影响,当考虑其相互影响时,在同走廊交直流线路中心附近,地面混合电场的瞬时最大值横向分布有波动;两种计算方法得到的地面混合电场有效值分布曲线基本重合;在一个交流周期内,同走廊线路地面混合电场的最大值与单独±800 kV直流线路地面合成电场的最大值差别很小.%Parallel adjacent erection of AC transmission lines and ±800 kV DC transmission lines in the same corridor will occur in China, so the calculation method for the hybrid electric field over the ground under this type of lines should be studied so as to satisfy the requirements of engineering design and environmental protection. Based on the analysis of mutual influences between AC transmission lines and ±800 kV DC transmission lines in the same corridor, a calculation method is proposed. Through the comparison between the calculation results achieved with this method and the corresponding calculation results obtained when the mutual influences between AC transmission lines and ±800 kV DC transmission lines are neglected, some conclusions can be drawn as follows: compared with the calculation results obtained when the mutual influences are neglected, near the center of AC transmission lines and ±800 kV DC transmission lines in the same corridor, the lateral distribution of the instantaneous maximal values of the hybrid electric field obtained with the proposed method fluctuates;the lateral distributions of the virtual values of the

  7. Advanced Testing Method for Ground Thermal Conductivity

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiaobing [ORNL; Clemenzi, Rick [Geothermal Design Center Inc.; Liu, Su [University of Tennessee (UT)

    2017-04-01

    A new method is developed that can quickly and more accurately determine the effective ground thermal conductivity (GTC) based on thermal response test (TRT) results. Ground thermal conductivity is an important parameter for sizing ground heat exchangers (GHEXs) used by geothermal heat pump systems. The conventional GTC test method usually requires a TRT for 48 hours with a very stable electric power supply throughout the entire test. In contrast, the new method reduces the required test time by 40%–60% or more, and it can determine GTC even with an unstable or intermittent power supply. Consequently, it can significantly reduce the cost of GTC testing and increase its use, which will enable optimal design of geothermal heat pump systems. Further, this new method provides more information about the thermal properties of the GHEX and the ground than previous techniques. It can verify the installation quality of GHEXs and has the potential, if developed, to characterize the heterogeneous thermal properties of the ground formation surrounding the GHEXs.

  8. Ground Water Quality of Selected Wells

    Directory of Open Access Journals (Sweden)

    Mosher R. Ahmed

    2013-05-01

    Full Text Available In order to characterize ground water quality in Zaweta district / Dohuk governorate, eight wells are selected to represent their water quality. Monthly samples are collected from the wells for the period from October 2005 to April 2006. The samples are tested for conductivity, total dissolved solids, pH, total hardness, chloride, alkalinity and nitrate according to the standard methods. The results of statistical analysis showed significant difference among the wells water quality in the measured parameters. Ground water quality of Zaweta district has high dissolved ions due to the nature of studied area rocks. Total dissolved solids of more than 1000 mg/l made the wells Gre-Qassroka, Kora and Swaratoka need to be treated to make taste palatable. Additionally high electrical conductivity and TDS made Zaweta ground water have a slight to moderate restriction to crop growth. The high alkalinity of Zaweta ground water indicated stabilized pH. The water quality of all the wells is found excessively hard. The nitrate concentration of Zaweta ground water ranged between 0.19-42.4 mg/l below the guidelines for WHO and the maximum nitrate concentration is recorded in Kora well .

  9. Hydrodynamic Modeling of Air Blast Propagation from the Humble Redwood Chemical High Explosive Detonations Using GEODYN

    Energy Technology Data Exchange (ETDEWEB)

    Chipman, V D

    2011-09-20

    Two-dimensional axisymmetric hydrodynamic models were developed using GEODYN to simulate the propagation of air blasts resulting from a series of high explosive detonations conducted at Kirtland Air Force Base in August and September of 2007. Dubbed Humble Redwood I (HR-1), these near-surface chemical high explosive detonations consisted of seven shots of varying height or depth of burst. Each shot was simulated numerically using GEODYN. An adaptive mesh refinement scheme based on air pressure gradients was employed such that the mesh refinement tracked the advancing shock front where sharp discontinuities existed in the state variables, but allowed the mesh to sufficiently relax behind the shock front for runtime efficiency. Comparisons of overpressure, sound speed, and positive phase impulse from the GEODYN simulations were made to the recorded data taken from each HR-1 shot. Where the detonations occurred above ground or were shallowly buried (no deeper than 1 m), the GEODYN model was able to simulate the sound speeds, peak overpressures, and positive phase impulses to within approximately 1%, 23%, and 6%, respectively, of the actual recorded data, supporting the use of numerical simulation of the air blast as a forensic tool in determining the yield of an otherwise unknown explosion.

  10. Influence of sulfate on cement mixtures containing fly ash or blast-furnace slag

    Energy Technology Data Exchange (ETDEWEB)

    Bhanumathidas, N.; Kalidas, N. [Inst. for Solid Waste Research and Ecological Balance, Visakhapatnam (India)

    2001-07-01

    The development of FaL-G, a cementitious mixture of fly ash, lime and gypsum was initiated by the desire to improve the early strength of blended portland cement. Fly ash and granulated blast-furnace slag both contain reactive alumina. The strength of some fly ash-lime mixtures, in the presence of gypsum, can be enhanced 3 to 6 times at all ages. This study showed that high-volume fly ash blended portland cements also increase in strength with the addition of gypsum or anhydrite. Ground granulated blast-furnace slag behaves in a similar manner to blended portland cement. The enhanced strength is due to the formation of calcium sulphoaluminate hydrates. This study shows that it is possible to use large volumes of fly ash and slag to conserve on cost-intensive and energy-intensive clinker. Bricks and blocks made according to FaL-G technology are replacing fired clay bricks used in masonry construction. This research is of particular interest for the conservation of agricultural soils, minerals and energy. The study also shows that it is possible to convert major industrial waste into useful construction products. 7 refs., 3 tabs., 1 fig.

  11. Integrating Gene Ontology and Blast to predict gene functions

    Institute of Scientific and Technical Information of China (English)

    WANG Cheng-gang; MO Zhi-hong

    2007-01-01

    A GoBlast system was built to predict gene function by integrating Blast search and Gene Ontology (GO) annotations together. The operation system was based on Debian Linux 3.1, with Apache as the web server and Mysql database as the data storage system. FASTA files with GO annotations were taken as the sequence source for blast alignment, which were formatted by wu-formatdb program. The GoBlast system includes three Bioperl modules in Perl: a data input module, a data process module and a data output module. A GoBlast query starts with an amino acid or nucleotide sequence. It ends with an output in an html page, presenting high scoring gene products which are of a high homology to the queried sequence and listing associated GO terms beside respective gene poducts. A simple click on a GO term leads to the detailed explanation of the specific gene function. This avails gene function prediction by Blast. GoBlast can be a very useful tool for functional genome research and is available for free at http://bioq.org/goblast.

  12. An Energy-Based Safety Evaluation Index of Blast Vibration

    Directory of Open Access Journals (Sweden)

    Mingsheng Zhao

    2015-01-01

    Full Text Available The combined peak particle velocity (PPV and frequency safety criterion for blast vibration is widely used in blasting engineering. However, some field investigations are inconsistent with this criterion. On the basis of field investigations, it is found that there are two failure modes of structures subjected to blasting seismic waves, that is, first-excursion failure and cumulative plastic damage failure. Moreover, the nature of structural responses under blast vibrations is a process of energy input, transformation, and dissipation. Therefore, an energy-based dual safety standard is proposed in this work to more comprehensively explain all failure modes of structures under blast vibrations. To this end, structures are simplified into elastic-plastic single degree of freedom (SDOF systems with bilinear restoring force models, and energy responses of SDOF systems are then determined using the Newmark-β method. From the energy responses, the maximum instantaneous input energy and hysteretic energy are selected as the basis of the dual safety criterion, because they can reflect first-excursion failure and cumulative plastic damage failure, respectively. Finally, field investigations in a blasting site in Zunyi, Guizhou province, China, are used to prove that compared to the PPV-frequency criterion the proposed energy-based dual safety criterion is more capable of assessing the damage potential of blast vibrations.

  13. Behavior of RCC Structural Members for Blast Analysis: A Review

    Directory of Open Access Journals (Sweden)

    Prof. C. M. Deshmukh

    2016-11-01

    Full Text Available n today’s scenario threat of enemies and terrorist attack is increasing. Therefore consideration of blast load in analysis and design is essential. A bomb explosion within or nearby outside the building can cause catastrophic failure of building. Blast loads have, in the recent past, become important service loads for certain categories of structure. An important task in blast resistance design is to make a realistic prediction of blast pressure. The distance of explosion from the structure is an important datum, governing the magnitude and duration of blast loads. In the present study, the RCC frame was analyzed by using conventional code for gravity loads using moment resisting frame. The blast load was calculated using UFC-340-02 (2008 or IS 4991-1968 for 500 kg and 100 Kg TNT at standoff distance of 10m and 30m from face of column at first floor level. The triangular impulse was applied as nodal time history at all front face joints. The analysis was performed using Computer aided software. The response of structure of will be evaluated under various blast scenarios. The response will be checked for safety of the structure on many parameters like displacement, acceleration and velocity.

  14. Explosively driven air blast in a conical shock tube

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, Joel B., E-mail: joel.b.stewart2.civ@mail.mil; Pecora, Collin, E-mail: collin.r.pecora.civ@mail.mil [U.S. Army Research Laboratory, Aberdeen Proving Ground, Maryland 21005 (United States)

    2015-03-15

    Explosively driven shock tubes present challenges in terms of safety concerns and expensive upkeep of test facilities but provide more realistic approximations to the air blast resulting from free-field detonations than those provided by gas-driven shock tubes. Likewise, the geometry of conical shock tubes can naturally approximate a sector cut from a spherically symmetric blast, leading to a better agreement with the blast profiles of free-field detonations when compared to those provided by shock tubes employing constant cross sections. The work presented in this article documents the design, fabrication, and testing of an explosively driven conical shock tube whose goal was to closely replicate the blast profile seen from a larger, free-field detonation. By constraining the blast through a finite area, large blasts (which can add significant damage and safety constraints) can be simulated using smaller explosive charges. The experimental data presented herein show that a close approximation to the free-field air blast profile due to a 1.5 lb charge of C4 at 76 in. can be achieved by using a 0.032 lb charge in a 76-in.-long conical shock tube (which translates to an amplification factor of nearly 50). Modeling and simulation tools were used extensively in designing this shock tube to minimize expensive fabrication costs.

  15. Explosively driven air blast in a conical shock tube.

    Science.gov (United States)

    Stewart, Joel B; Pecora, Collin

    2015-03-01

    Explosively driven shock tubes present challenges in terms of safety concerns and expensive upkeep of test facilities but provide more realistic approximations to the air blast resulting from free-field detonations than those provided by gas-driven shock tubes. Likewise, the geometry of conical shock tubes can naturally approximate a sector cut from a spherically symmetric blast, leading to a better agreement with the blast profiles of free-field detonations when compared to those provided by shock tubes employing constant cross sections. The work presented in this article documents the design, fabrication, and testing of an explosively driven conical shock tube whose goal was to closely replicate the blast profile seen from a larger, free-field detonation. By constraining the blast through a finite area, large blasts (which can add significant damage and safety constraints) can be simulated using smaller explosive charges. The experimental data presented herein show that a close approximation to the free-field air blast profile due to a 1.5 lb charge of C4 at 76 in. can be achieved by using a 0.032 lb charge in a 76-in.-long conical shock tube (which translates to an amplification factor of nearly 50). Modeling and simulation tools were used extensively in designing this shock tube to minimize expensive fabrication costs.

  16. Evaluation of blast-induced vibration effects on structures 1

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Rim; Jeon, Gyu Shick; Lee, Dae Soo; Joo, Kwang Ho; Lee, Woong Keon [Korea Electrotechnology Research Inst., Changwon (Korea, Republic of); Ryu, Chang Ha; Chung, So Keul; Lee, Kyung Won; Shin, Hee Soon; Chun, Sun Woo; Park, Yeon Jun; Synn, Joong Ho; Choi, Byung Hee [Korea Inst. of Geology Mining and Materials, Taejon (Korea, Republic of)

    1995-12-31

    Due to the difficulties of obtaining construction site for new plants, following ones are inevitably being built in the site adjacent to existing power plants. Therefore considerable thought has been recently given to the dynamic loading generated by blasting works near the plants to maintain the safety of structures and facilities in power plants. Our own standard for safety level of blast vibration is not prepared yet, and foreign standards have been generally employed without theoretical and experimental verification. Safety-related structures of power plants and facilities have to be protected against the effects of possible hazards due to blast vibration. Earthquakes have been considered a major dynamic design loading as a requirement of plant design, but the effects of blast-induced vibration are not. In order to ensure the safety, rational safe criterion should be established and blast design should be satisfy it, which requires the development of a model for prediction of vibration level through more systematic measurement and analysis. The main objectives of the study are : to provide background data for establishing the rational safe vibration limits, to develop models for prediction of blast vibration level, to establish safe blast design criterion, and to accumulate techniques for field measurements, data acquisition and analysis (author). 80 refs., 347 figs.

  17. Modelling and Testing of Blast Effect On the Structures

    Science.gov (United States)

    Figuli, Lucia; Jangl, Štefan; Papán, Daniel

    2016-10-01

    As a blasting agent in the blasting and mining engineering, has been using one of so called new generation of explosives which offer greater flexibility in their range and application, and such explosive is ANFO. It is type of explosive consists of an oxidiser and a fuel (ammonium nitrate and fuel oil). One of such ANFO explosives which are industrially made in Slovakia is POLONIT. The explosive is a mixture of ammonium nitrate, methyl esters of higher fatty acids, vegetable oil and red dye. The paper deals with the analysis of structure subjected to the blast load created by the explosion of POLONIT charge. First part of paper is describing behaviour and characteristic of blast wave generated from the blast (detonation characteristics, physical characteristics, time-history diagram etc.) and the second part presents the behaviour of such loaded structures, because of the analysis of such dynamical loaded structure is required knowing the parameters of blast wave, its effect on structure and the tools for the solution of dynamic analysis. The real field tests of three different weight of charges and two different structures were done. The explosive POLONIT was used together with 25 g of ignition explosive PLNp10. Analytical and numerical model of blast loaded structure is compared with the results obtained from the field tests (is compared with the corresponding experimental accelerations). For the modelling structures were approximated as a one-degree system of freedom (SDOF), where the blast wave was estimated with linear decay and exponential decay using positive and negative phase of blast wave. Numerical solution of the steel beam dynamic response was performed via FEM (Finite Element Method) using standard software Visual FEA.

  18. FDTD simulation of LEMP propagation over lossy ground: Influence of distance, ground conductivity, and source parameters

    Science.gov (United States)

    Aoki, Masanori; Baba, Yoshihiro; Rakov, Vladimir A.

    2015-08-01

    We have computed lightning electromagnetic pulses (LEMPs), including the azimuthal magnetic field Hφ, vertical electric field Ez, and horizontal (radial) electric field Eh that propagated over 5 to 200 km of flat lossy ground, using the finite difference time domain (FDTD) method in the 2-D cylindrical coordinate system. This is the first systematic full-wave study of LEMP propagation effects based on a realistic return-stroke model and including the complete return-stroke frequency range. Influences of the return-stroke wavefront speed (ranging from c/2 to c, where c is the speed of light), current risetime (ranging from 0.5 to 5 µs), and ground conductivity (ranging from 0.1 mS/m to ∞) on Hφ, Ez, and Eh have been investigated. Also, the FDTD-computed waveforms of Eh have been compared with the corresponding ones computed using the Cooray-Rubinstein formula. Peaks of Hφ, Ez, and Eh are nearly proportional to the return-stroke wavefront speed. The peak of Eh decreases with increasing current risetime, while those of Hφ and Ez are only slightly influenced by it. The peaks of Hφ and Ez are essentially independent of the ground conductivity at a distance of 5 km. Beyond this distance, they appreciably decrease relative to the perfectly conducting ground case, and the decrease is stronger for lower ground conductivity values. The peak of Eh increases with decreasing ground conductivity. The computed Eh/Ez is consistent with measurements of Thomson et al. (1988). The observed decrease of Ez peak and increase of Ez risetime due to propagation over 200 km of Florida soil are reasonably well reproduced by the FDTD simulation with ground conductivity of 1 mS/m.

  19. Renewable Energy Opportunties at Dugway Proving Ground, Utah

    Energy Technology Data Exchange (ETDEWEB)

    Orrell, Alice C.; Kora, Angela R.; Russo, Bryan J.; Horner, Jacob A.; Williamson, Jennifer L.; Weimar, Mark R.; Gorrissen, Willy J.; Nesse, Ronald J.; Dixon, Douglas R.

    2010-05-31

    This document provides an overview of renewable resource potential at Dugway Proving Ground, based primarily upon analysis of secondary data sources supplemented with limited on-site evaluations. This effort focuses on grid-connected generation of electricity from renewable energy sources and ground source heat pumps (GSHPs). The effort was funded by the U.S. Army Installation Management Command (IMCOM) as follow-on to the 2005 Department of Defense (DoD) Renewables Assessment.

  20. Characteristics and mechanisms of cardiopulmonary injury caused by mine blasts in shoals: a randomized controlled study in a rabbit model.

    Directory of Open Access Journals (Sweden)

    Gengfen Han

    Full Text Available BACKGROUND: Because the characteristics of blast waves in water are different from those in air and because kinetic energy is liberated by a pressure wave at the water-air interface, thoracic injuries from mine blasts in shoals may be serious. The aim of the present study was to investigate the characteristics and mechanisms of cardiopulmonary injury caused by mine blasts in shoals. METHODS: To study the characteristics of cardiopulmonary injury, 56 animals were divided randomly into three experimental groups (12 animals in the sham group, 22 animals in the land group and 22 animals in the shoal group. To examine the biomechanics of injury, 20 animals were divided randomly into the land group and the shoal group. In the experimental model, the water surface was at the level of the rabbit's xiphoid process, and paper electric detonators (600 mg RDX were used to simulate mines. Electrocardiography and echocardiography were conducted, and arterial blood gases, serum levels of cardiac troponin I and creatine kinase-MB and other physiologic parameters were measured over a 12-hour period after detonation. Pressures in the thorax and abdomen and the acceleration of the thorax were measured. CONCLUSION: The results indicate that severe cardiopulmonary injury and dysfunction occur following exposure to mine blasts in shoals. Therefore, the mechanisms of cardiopulmonary injury may result from shear waves that produce strain at the water-air interface. Another mechanism of injury includes the propagation of the shock wave from the planta to the thorax, which causes a much higher peak overpressure in the abdomen than in the thorax; as a result, the abdominal organs and diaphragm are thrust into the thorax, damaging the lungs and heart.

  1. Computation of Blast Pressures foam Propellant for Compaction of Soil

    Directory of Open Access Journals (Sweden)

    K. B. Agarwal

    1974-01-01

    Full Text Available The knowledge of blast pressure characteristics is a pre-requisite for a suitable application of foam propellant to emergency military construction such as compacting of the soil from an aircraft using the foam propellant. The foam propellant considered here is a combination of hydrazine and ammonium perchlorate. The blast pressure is found to be a function of the quantity of foam propellant used and the distance of the observation point. This paper attempts to compute the blast pressure versus time characteristics of a foam propellant strip.

  2. Hybrid S2/Carbon Epoxy Composite Armours Under Blast Loads

    Science.gov (United States)

    Dolce, F.; Meo, Michele; Wright, A.; French, M.; Bernabei, M.

    2012-06-01

    Civil and military structures, such as helicopters, aircrafts, naval ships, tanks or buildings are susceptible to blast loads as terroristic attacks increases, therefore there is the need to design blast resistant structures. During an explosion the peak pressure produced by shock wave is much greater than the static collapse pressure. Metallic structures usually undergo large plastic deformations absorbing blast energy before reaching equilibrium. Due to their high specific properties, fibre-reinforced polymers are being considered for energy absorption applications in blast resistant armours. A deep insight into the relationship between explosion loads, composite architecture and deformation/fracture behaviour will offer the possibility to design structures with significantly enhanced energy absorption and blast resistance performance. This study presents the results of a numerical investigation aimed at understanding the performance of a hybrid composite (glass/carbon fibre) plate subjected to blast loads using commercial LS-DYNA software. In particular, the paper deals with numerical 3D simulations of damages caused by air blast waves generated by C4 charges on two fully clamped rectangular plates made of steel and hybrid (S2/Carbon) composite, respectively. A Multi Materials Arbitrary Lagrangian Eulerian (MMALE) formulation was used to simulate the shock phenomenon. For the steel plates, the Johnson-Cook material model was employed. For the composite plates both in-plane and out-of-plane failure criteria were employed. In particular, a contact tiebreak formulation with a mixed mode failure criteria was employed to simulate delamination failure. As for the steel plates the results showed that excellent correlation with the experimental data for the two blast load conditions in terms of dynamic and residual deflection for two different C4 charges. For the composite plates the numerical results showed that, as expected, a wider delamination damage was observed

  3. Evaluation of copper slag blast media for railcar maintenance

    Science.gov (United States)

    Sagers, N. W.; Finlayson, Mack H.

    1989-01-01

    Copper slag was tested as a blasting substitute for zirconium silicate which is used to remove paint from railroad cars. The copper slag tested is less costly, strips paint faster, is produced near the point of need, provides a good bonding surface for paint, and permits the operator to work in a more comfortable position, i.e., standing nearly erect instead of having to crouch. Outdoor blasting with the tested Blackhawk (20 to 40 mesh) copper slag is also environmentally acceptable to the State of Utah. Results of tests for the surface erosion rate with copper slag blasting are included.

  4. Evaluation of copper slag blast media for railcar maintenance

    Science.gov (United States)

    Sagers, N. W.; Finlayson, Mack H.

    1989-06-01

    Copper slag was tested as a blasting substitute for zirconium silicate which is used to remove paint from railroad cars. The copper slag tested is less costly, strips paint faster, is produced near the point of need, provides a good bonding surface for paint, and permits the operator to work in a more comfortable position, i.e., standing nearly erect instead of having to crouch. Outdoor blasting with the tested Blackhawk (20 to 40 mesh) copper slag is also environmentally acceptable to the State of Utah. Results of tests for the surface erosion rate with copper slag blasting are included.

  5. Portland cement-blast furnace slag blends in oilwell cementing applications

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, D.T.; DiLullo, G.; Hibbeler, J. [and others

    1995-12-31

    Recent investigations of blast furnace slag cementing technologies. have been expanded to include Portland cement/blast furnace slag blends. Mixtures of Portland cement and blast furnace slag, while having a long history of use in the construction industry, have not been used extensively in oilwell cementing applications. Test results indicate that blending blast furnace slag with Portland cement produces a high quality well cementing material. Presented are the design guidelines and laboratory test data relative to mixtures of blast furnace slag and Portland cements. Case histories delineating the use of blast furnace slag - Portland cement blends infield applications are also included.

  6. Promising blast resistance entries from 20th-23rd IRBN in Hangzhou

    Institute of Scientific and Technical Information of China (English)

    ZHUPeiliang; YUANXiaoping; ZHAOXinhua; SHENYing

    1994-01-01

    Evaluation for blast resistances of rice entries of 20th to 23rd International Rice Blast Nursery (IRBN) was conducted at CNRRI during 1990-1993. The resistance to seedling blast (SB)was evaluated in a greenhouse at 3-4 leaf stage with artificial inoculation while resistance to leaf blast (LB) and neck blast (NB) were evaluated in the natural field as instructed by the International Network of Genetic Evaluation for Rice (INGER). Materials with high level of blast resistante and good agronomic traits were selected andre-evaluated in suoceeding years.

  7. Ground Enterprise Management System Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Emergent Space Technologies Inc. proposes to develop the Ground Enterprise Management System (GEMS) for spacecraft ground systems. GEMS will provide situational...

  8. Slag wool manufacturing from blast furnace slag

    Directory of Open Access Journals (Sweden)

    Володимир Петрович Руських

    2016-11-01

    Full Text Available Slag wool is the most expensive and valuable product of blast furnace slag processing. Slag wool is in great demand nowadays. The article highlights the factors influencing the mineral wool quality: chemical composition that determines the acidity of the module, the temperature of the molten slag and the required slag jet thickness consistency. Mineral wool is produced by blowing air or steam into a jet of molten slag. As a result of it the slag crushes into droplets stretching. The resulting wool contains 5% slag and 95% air. The quality of the obtained slag wool depends on the module acidity of the slag. The blast furnace slags of «Ilyich iron and steel works of Mariupol» and «Azovstal iron & steel works» are the main (short slags – they give short fibers. To obtain high-quality long fiber wool it is necessary to add admixtures into basic blast furnace slag to reduce its basicity. As a result of the fuel and energy rising prices and the necessity to reduce the slag wool cost it is necessary to develop a new technology with fiery-liquid slag, with the removal of iron compounds and sulphur from the melts and the introduction of corrective additives to improve the quality of slag wool. Good thermal conductivity (about 0,03 kcal/m∙h∙°C and other indicators (resistance, volume weight make it possible to use the materials from slag wool (pads, rigid and semi-rigid plates as heat and sound insulating materials

  9. Effects of the addition of functional electrical stimulation to ground level gait training with body weight support after chronic stroke Efeitos da adição da estimulação elétrica funcional ao treino de marcha em piso fixo com suporte parcial de peso após acidente vascular encefálico crônico

    Directory of Open Access Journals (Sweden)

    Christiane L. Prado-Medeiros

    2011-12-01

    Full Text Available BACKGROUND: The addition of functional electrical stimulation (FES to treadmill gait training with partial body weight support (BWS has been proposed as a strategy to facilitate gait training in people with hemiparesis. However, there is a lack of studies that evaluate the effectiveness of FES addition on ground level gait training with BWS, which is the most common locomotion surface. OBJECTIVE: To investigate the additional effects of commum peroneal nerve FES combined with gait training and BWS on ground level, on spatial-temporal gait parameters, segmental angles, and motor function. METHODS: Twelve people with chronic hemiparesis participated in the study. An A1-B-A2 design was applied. A1 and A2 corresponded to ground level gait training using BWS, and B corresponded to the same training with the addition of FES. The assessments were performed using the Modified Ashworth Scale (MAS, Functional Ambulation Category (FAC, Rivermead Motor Assessment (RMA, and filming. The kinematics analyzed variables were mean walking speed of locomotion; step length; stride length, speed and duration; initial and final double support duration; single-limb support duration; swing period; range of motion (ROM, maximum and minimum angles of foot, leg, thigh, and trunk segments. RESULTS: There were not changes between phases for the functional assessment of RMA, for the spatial-temporal gait variables and segmental angles, no changes were observed after the addition of FES. CONCLUSION: The use of FES on ground level gait training with BWS did not provide additional benefits for all assessed parameters.CONTEXTUALIZAÇÃO: A adição da estimulação elétrica funcional (EEF ao treino de marcha em esteira, com sistema de suporte parcial de peso corporal (SPPC, tem sido proposta como estratégia para melhorar a marcha em hemiparéticos. Entretanto, nenhum estudo verificou a eficácia da adição da EEF ao treino de marcha com SPPC em piso fixo, a superfície mais

  10. GROUND VIBRATIONS LEVEL CHARACTERIZATION THROUGH THE GEOLOGICAL STRENGTH INDEX (GSI

    Directory of Open Access Journals (Sweden)

    Josip Mesec

    2017-01-01

    Full Text Available This paper analyses the results of trial, construction and quarry blasting, carried out in sediment rock deposits, mainly limestone and dolomite, at diff erent locations in the Republic of Croatia. The division of the three test groups was based on the lithology changes and GSI values of the rock units at these locations. The peak particle velocity measurements with 246 recorded events, was conducted during a long period of six years. Based on the results of seismic measurements, the empirical relationships between peak particle velocity and scaled distance were established for each group. In order to establish a useful relationship between peak particle velocity and scaled distance, simple regression analysis was conducted with the Blastware software program from Instantel. The results of this study can be used to characterize ground vibration levels to the environment, through the geological strength index (GSI.

  11. Design for the 145MW blast furnance gas firing gas turbine combined cycle plant

    Energy Technology Data Exchange (ETDEWEB)

    Takano, H. (Kawasaki Steel Corp., Chiba (Japan). Technical Research Lab.); Kitauchi, Y.; Hiura, H. (Mitsubishi Heavy Industries Ltd., Takasago, Hyogo (Japan). Takasago Works)

    1988-01-01

    A 145 MW blast furnance gas firing gas turbine combined cycle plant was designed and installed in a steel works of Japan as a repowering unit. A 124 MW large scale gas turbine with turbine inlet temperature 1150{sup {degrees}}C (1423 K) was adopted as a core engine for the combined cycle plant. The fuel of this gas turbine is blast furnace gas mixed with coke oven gas which are byproducts in steel works, and the calorific value of the mixed gas to be controlled is about 1000 kcal/Nm{sup 3} (4187 kJ/Nm{sup 3}). A specially designed multi-cannular type combustor was developed to burn such a low BTV fuel. The gas turbine, generator, steam turbine and fuel gas compressor are connected to make a single shaft configuration. As a result of this introducing the gas turbine combined cycle plant, the plant thermal efficiency was achieved above 45% (at NET) and the total electricity generation in the works is increased from 243 MW to 317 MW. This paper describes the design features of this combined cycle plant.

  12. Safety standards of electrical equipment in surface mines. [USSR

    Energy Technology Data Exchange (ETDEWEB)

    Zhidkov, V.O.; Il' in, Yu.N.; Neyaskin, D.V.

    1985-03-01

    Modified safety regulations developed by the VostNII Institute are discussed. The safety regulations for electrical equipment used in surface coal mines are modifications of general safety regulations in coal surface mining. The modified regulations cover: improved protection from short circuits and grounds in electrical systems with voltage higher than 1000 V, protection systems for heavy-duty electric motors and motors with thyristor control, operation of power shovels on benches with contact systems (hazards of damage to electric cables caused by moving mining equipment), operation of electrical equipment and contact systems on benches at which trucks are used for mine haulage (hazards of damage to electric cables by moving trucks).

  13. Polarization dynamics in optical ground wire network.

    Science.gov (United States)

    Leeson, Jesse; Bao, Xiaoyi; Côté, Alain

    2009-04-20

    We report the polarization dynamics in an optical ground wire (OPGW) network for a summer period and a fall period for what is believed to be the first time. To better observe the surrounding magnetic fields contribution to modulating the state of polarization (SOP) we installed a Faraday rotating mirror to correct reciprocal birefringence from quasi-static changes. We also monitored the OPGW while no electrical current was present in the towers' electrical conductors. The spectral analysis, the arc length mapped out over a given time interval on a Poincaré sphere, histograms of the arc length, and the SOP autocorrelation function are calculated to analyze the SOP changes. Ambient temperature changes, wind, Sun-induced temperature gradients, and electrical current all have a significant impact on the SOP drift in an OPGW network. Wind-generated cable oscillations and Sun-induced temperature gradients are shown to be the dominant slow SOP modulations, while Aeolian vibrations and electrical current are shown to be the dominant fast SOP modulations. The spectral analysis revealed that the electrical current gives the fastest SOP modulation to be 300 Hz for the sampling frequency of 1 KHz. This has set the upper speed limit for real-time polarization mode dispersion compensation devices.

  14. Carbonation Characteristics of Alkali-Activated Blast-Furnace Slag Mortar

    Directory of Open Access Journals (Sweden)

    Keum-Il Song

    2014-01-01

    Full Text Available Alkali-activated ground granulated blast-slag (AAS is the most obvious alternative material for ordinary Portland cement (OPC. However, to use it as a structural material requires the assessment and verification of its durability. The most important factor for a durability evaluation is the degree of carbonation resistance, and AAS is known to show lower performance than OPC. A series of experiments was conducted with a view to investigate the carbonation characteristics of AAS binder. As a consequence, it was found that the major hydration product of AAS was calcium silicate hydrate (CSH, with almost no portlandite, unlike the products of OPC. After carbonation, the CSH of AAS turned into amorphous silica gel which was most likely why the compressive strength of AAS became weaker after carbonation. An increase of the activator dosage leads AAS to react more quickly and produce more CSH, increasing the compaction, compressive strength, and carbonation resistance of the microstructure.

  15. Reinventing Grounded Theory: Some Questions about Theory, Ground and Discovery

    Science.gov (United States)

    Thomas, Gary; James, David

    2006-01-01

    Grounded theory's popularity persists after three decades of broad-ranging critique. In this article three problematic notions are discussed--"theory," "ground" and "discovery"--which linger in the continuing use and development of grounded theory procedures. It is argued that far from providing the epistemic security promised by grounded theory,…

  16. Size of craters produced by explosive charges on or above the ground surface

    Science.gov (United States)

    Ambrosini, R. D.; Luccioni, B. M.; Danesi, R. F.; Riera, J. D.; Rocha, M. M.

    The results of a series of tests performed with different amounts of explosive at short distances above and below ground level, as well as on the soil surface are briefly described. After an introductory description of both the main features of the blast wave and the mechanics of crater formation, a brief review of empirical methods for crater size prediction is presented. Next, the experimental design and the results obtained are described. The crater dimensions for underground explosions coincide with those found in the literature. For explosions at ground level the results are qualitatively described by empirical equations. For explosive charges situated above ground level, the dimensions of the craters are smaller than those observed in underground and near the surface explosions. Two new single prediction equations for this case are presented.

  17. H-BLAST: a fast protein sequence alignment toolkit on heterogeneous computers with GPUs.

    Science.gov (United States)

    Ye, Weicai; Chen, Ying; Zhang, Yongdong; Xu, Yuesheng

    2017-04-15

    The sequence alignment is a fundamental problem in bioinformatics. BLAST is a routinely used tool for this purpose with over 118 000 citations in the past two decades. As the size of bio-sequence databases grows exponentially, the computational speed of alignment softwares must be improved. We develop the heterogeneous BLAST (H-BLAST), a fast parallel search tool for a heterogeneous computer that couples CPUs and GPUs, to accelerate BLASTX and BLASTP-basic tools of NCBI-BLAST. H-BLAST employs a locally decoupled seed-extension algorithm for better performance on GPUs, and offers a performance tuning mechanism for better efficiency among various CPUs and GPUs combinations. H-BLAST produces identical alignment results as NCBI-BLAST and its computational speed is much faster than that of NCBI-BLAST. Speedups achieved by H-BLAST over sequential NCBI-BLASTP (resp. NCBI-BLASTX) range mostly from 4 to 10 (resp. 5 to 7.2). With 2 CPU threads and 2 GPUs, H-BLAST can be faster than 16-threaded NCBI-BLASTX. Furthermore, H-BLAST is 1.5-4 times faster than GPU-BLAST. https://github.com/Yeyke/H-BLAST.git. yux06@syr.edu. Supplementary data are available at Bioinformatics online.

  18. Evaluation and Genetic Analysis of Five Parental Varieties Resistant to Rice Blast Pathogen in Heilongjiang Province

    Institute of Scientific and Technical Information of China (English)

    Zhang Zhong-chen; Liu Hong-liang; Gao Hong-xiu; Liu Hai-ying; Jin Zheng-xun

    2012-01-01

    Five F2 segregation populations, derived from crosses between the susceptible japonica cultivars (cvs.) Kongyul31 and donor cvs. Aichi Asahi (AA), BL1, Digu, Pai-kan-tao (PKT) and Oryzica Llanos 5 (ORL5), were used to evaluate their natural resistance to blast in cold region. The field test of their blast resistance was conducted in 858 Farm, which showed that Aichi Asahi, BL 1 and Digu were highly resistant to either leaf blast or neck blast and could be used to develop molecular breeding by design, and genetic analysis indicated that the field resistance of Aichi Asahi, BLland Digu to leaf blast and neck blast was controlled by a single dominant gene, and the leaf blast and neck blast resistance in the donor cv. Pai-kan-tao was inherited as a single recessive gene, the neck blast resistance of the donor cv. Oryzica Llanos 5 was controlled by a single recessive gene while its leaf blast resistance was not controlled by this gene. These results suggested that five parental varieties positively contributed to resistance to either leaf blast or neck blast and could be used to expand the genetic germplasms resistant to blast in cold region using molecular assisted selection.

  19. Ground water in Oklahoma

    Science.gov (United States)

    Leonard, A.R.

    1960-01-01

    One of the first requisites for the intelligent planning of utilization and control of water and for the administration of laws relating to its use is data on the quantity, quality, and mode of occurrence of the available supplies. The collection, evaluation and interpretation, and publication of such data are among the primary functions of the U.S. Geological Survey. Since 1895 the Congress has made appropriations to the Survey for investigation of the water resources of the Nation. In 1929 the Congress adopted the policy of dollar-for-dollar cooperation with the States and local governmental agencies in water-resources investigations of the U.S. Geological Survey. In 1937 a program of ground-water investigations was started in cooperation with the Oklahoma Geological Survey, and in 1949 this program was expanded to include cooperation with the Oklahoma Planning and Resources Board. In 1957 the State Legislature created the Oklahoma Water Resources Board as the principal State water agency and it became the principal local cooperator. The Ground Water Branch of the U.S. Geological Survey collects, analyzes, and evaluates basic information on ground-water resources and prepares interpretive reports based on those data. Cooperative ground-water work was first concentrated in the Panhandle counties. During World War II most work was related to problems of water supply for defense requirements. Since 1945 detailed investigations of ground-water availability have been made in 11 areas, chiefly in the western and central parts of the State. In addition, water levels in more than 300 wells are measured periodically, principally in the western half of the State. In Oklahoma current studies are directed toward determining the source, occurrence, and availability of ground water and toward estimating the quantity of water and rate of replenishment to specific areas and water-bearing formations. Ground water plays an important role in the economy of the State. It is

  20. Preliminary Electrical Designs for CTEX and AFIT Satellite Ground Station

    Science.gov (United States)

    2010-03-01

    activated failsafe marker != 0 = 0 Tube 2 Tube 3 Shutdown Describes the primary operation of the experiment control system. [DiS01] Tube Processes: Each...the 400-1,200 nm range. This band is known to contain peaks for Hematites , Geothites and other iron bearing minerals [2]. Looking at this data and...Motion Controllers Motor Amplifier PSU DCCU Power 12-30V DC 56V AC USB General Purpose I/O 32-PIN Proprietary Connection Ethernet Primary Data