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Zhou H.,KTH Royal Institute of Technology | Diendorfer G.,System Detection | Thottappillil R.,KTH Royal Institute of Technology | Pichler H.,System Detection | Mair M.,Central Institute for Meteorology and Geodynamics
Journal of Geophysical Research: Atmospheres | Year: 2012

We report the measured current characteristics of positive lightning discharges to the Gaisberg Tower (GBT) in Austria from 2000 to 2009. On the basis of the recorded current waveforms, a total of 26 flashes consisting of initial stage only were identified as upward positive discharges initiated by an upward negative leader from GBT. They accounted for 4% (26/652) of the total flashes recorded at the GBT. Nineteen (73%) out of the 26 positive flashes occurred during nonconvective season (September-March). Median values of flash peak current, flash duration, charge transfer, and action integral were determined as 5.2 kA, 82 ms, 58 C, and 0.16 × 103 A2 s, respectively. Current pulses of high repetition rate superimposed on the initial portion of initial continuous current are inferred to be associated with the upward negative stepped leader process. The weighted arithmetic means of leader pulse peak current, leader pulse duration, leader interpulse interval, and leader pulse charge are 3 kA, 31 μs, 32 μs, and 42 mC, respectively. On the basis of an assumed stepped leader speed in the range of 8 × 104 to 4.5 × 105 m/s an upward negative stepped leader channel charge density of 15-87 mC/m, a leader length of 168-945 m, and an average leader step length of 2.4-13.3 m were estimated. The upward negative stepped leader channel charge density and length are significantly larger and smaller than their counterparts in downward negative stepped leaders, respectively, while the upward leader step length is consistent with previous studies. Possible reasons for this are discussed. © 2012 by the American Geophysical Union.


Zhou H.,KTH Royal Institute of Technology | Diendorfer G.,System Detection | Thottappillil R.,KTH Royal Institute of Technology | Pichler H.,System Detection | Mair M.,Central Institute for Meteorology and Geodynamics
Journal of Geophysical Research: Atmospheres | Year: 2012

We examine in detail the simultaneous lightning current waveforms, close electric field changes, and lightning location system data for upward lightning discharges initiated from the Gaisberg Tower (GBT) from 2005 to 2009. Out of 205 upward flashes, most of them (87% or 179/205) were initiated from the tower top without any nearby preceding lightning activity (called "self- initiated"), whereas 26 upward flashes (13%) were initiated from the tower top with immediately preceding nearby lightning activity (called "nearby-lightning-triggered"), including 15 positive ground flashes, one negative ground flashes, and 10 cloud discharges. The possible reasons for self-initiated upward flashes dominating at the GBT could be the field enhancement due to the Gaisberg Mountain above the surrounding terrain and low altitude of charge region during non-convective season (September to March), since we note that self-initiated lightning at the GBT occurred predominantly (79% or 142/179) during non-convective season. On the other hand the majority (85% or 22/26) of nearby-lightning-triggered upward flashes at the GBT occurring during convective season (April to August) and 80 nearby-lightning-triggered upward flashes out of 81 upward flashes observed at the ten tall towers in Rapid City in South Dakota of USA occurring during summer seasons, could be due to the result of high altitude of charge region. The triggering flashes were detected to be within 1 and 18km distance and the time intervals between them and upward lightning initiation are in the range of 0.3 to 90.7ms. Copyright 2012 by the American Geophysical Union.


Zhou H.,KTH Royal Institute of Technology | Thottappillil R.,KTH Royal Institute of Technology | Diendorfer G.,System Detection
Electric Power Systems Research | Year: 2014

We derive electric field expressions, associated with lightning strikes to a tall object, using the monopole (Continuity Equation) technique which is distinctly different from the traditional dipole (Lorentz Condition) technique. Expressions to calculate the charge density along the tall object and lightning channel based on the assumptions of the transmission line model of the lightning strikes to a tall object and a series point current source placed at the object top, are also derived. These expressions are used to calculate the very close-range electric fields in the monopole (Continuity Equation) technique in terms of the retarded current and charge density along the tower and lightning channel and their results are compared with those calculated from the traditional dipole (Lorentz Condition) technique in terms of the retarded current along the tower and lightning channel. Alternative explanations are provided to the inversion of polarity of the vertical electric field at very close range based on distribution of charge density along the tower and lightning channel. © 2014 Elsevier B.V.


Zhou H.,KTH Royal Institute of Technology | Diendorfer G.,System Detection | Thottappillil R.,KTH Royal Institute of Technology | Pichler H.,System Detection | Mair M.,Central Institute for Meteorology and Geodynamics
Journal of Geophysical Research: Atmospheres | Year: 2011

We analyze current records for 21 upward initiated bipolar lightning flashes observed at the Gaisberg Tower (GBT) in Austria from 2000 to 2009. A bipolar lightning flash occurrence of 3% (21/652) is found during the 10-year observation period. Thirteen (62% or 13/21) of them occurred in nonconvective season (September-March). On the basis of the classification suggested by Rakov and Uman (2003), 13 (62%) of the 21 bipolar flashes belong to Type 1 associated with a polarity reversal during the initial stage (IS) current, five belong to Type 2 associated with different polarities of the IS current and the following return strokes, one belongs to Type 3 associated with return strokes of opposite polarity following the IS, and two of them are not assigned. We also find that the initial polarity reversal from negative to positive occurs more often (76% or 16/21) than that from positive to negative within a bipolar flash, in agreement with observations in other studies. The geometric mean (GM) and arithmetic mean (AM) of the total absolute charge transfer are 99.5 C and 125 C, with the GM and AM total flash duration of 320 ms and 396 ms, respectively. From simultaneous current and high-speed video measurements of one bipolar flash, within the field of view, the positive charge was transferred along one branch initially, followed by the negative charge transfer after cessation of the luminosity for 142 ms, while the other two branches connected to the main channel always contributed to the negative charge transfer during the whole process. © 2011 by the American Geophysical Union.


News Article | November 14, 2016
Site: marketersmedia.com

Wiseguyreports.Com Adds “Anti-Drone -Market Demand, Growth, Opportunities and analysis of Top Key Player Forecast to 2021” To Its Research Database This report studies sales (consumption) of Anti-Drone in Global market, especially in United States, China, Europe, Japan, focuses on top players in these regions/countries, with sales, price, revenue and market share for each player in these regions, covering Request for Sample Report @ https://www.wiseguyreports.com/sample-request/736043-global-anti-drone-sales-market-report-2016 Market Segment by Regions, this report splits Global into several key Regions, with sales (consumption), revenue, market share and growth rate of Anti-Drone in these regions, from 2011 to 2021 (forecast), like United States China Europe Japan Split by product Types, with sales, revenue, price and gross margin, market share and growth rate of each type, can be divided into Detection System Detection and Disruption Type III Split by applications, this report focuses on sales, market share and growth rate of Anti-Drone in each application, can be divided into Military and Defense Commercial Homeland Security Global Anti-Drone Sales Market Report 2016 1 Anti-Drone Overview 1.1 Product Overview and Scope of Anti-Drone 1.2 Classification of Anti-Drone 1.2.1 Detection System 1.2.2 Detection and Disruption 1.2.3 Type III 1.3 Application of Anti-Drone 1.3.1 Military and Defense 1.3.2 Commercial 1.3.3 Homeland Security 1.4 Anti-Drone Market by Regions 1.4.1 United States Status and Prospect (2011-2021) 1.4.2 China Status and Prospect (2011-2021) 1.4.3 Europe Status and Prospect (2011-2021) 1.4.4 Japan Status and Prospect (2011-2021) 1.5 Global Market Size (Value and Volume) of Anti-Drone (2011-2021) 1.5.1 Global Anti-Drone Sales and Growth Rate (2011-2021) 1.5.2 Global Anti-Drone Revenue and Growth Rate (2011-2021) 7 Global Anti-Drone Manufacturers Analysis 7.1 The Boeing Company 7.1.1 Company Basic Information, Manufacturing Base and Competitors 7.1.2 Anti-Drone Product Type, Application and Specification 7.1.2.1 Type I 7.1.2.2 Type II 7.1.3 The Boeing Company Anti-Drone Sales, Revenue, Price and Gross Margin (2011-2016) 7.1.4 Main Business/Business Overview 7.2 Airbus Group SE 7.2.1 Company Basic Information, Manufacturing Base and Competitors 7.2.2 109 Product Type, Application and Specification 7.2.2.1 Type I 7.2.2.2 Type II 7.2.3 Airbus Group SE Anti-Drone Sales, Revenue, Price and Gross Margin (2011-2016) 7.2.4 Main Business/Business Overview 7.3 SAAB AB 7.3.1 Company Basic Information, Manufacturing Base and Competitors 7.3.2 122 Product Type, Application and Specification 7.3.2.1 Type I 7.3.2.2 Type II 7.3.3 SAAB AB Anti-Drone Sales, Revenue, Price and Gross Margin (2011-2016) 7.3.4 Main Business/Business Overview 7.4 Thales Group 7.4.1 Company Basic Information, Manufacturing Base and Competitors 7.4.2 Oct Product Type, Application and Specification 7.4.2.1 Type I 7.4.2.2 Type II 7.4.3 Thales Group Anti-Drone Sales, Revenue, Price and Gross Margin (2011-2016) 7.4.4 Main Business/Business Overview 7.5 Lockheed Martin Corporation 7.5.1 Company Basic Information, Manufacturing Base and Competitors 7.5.2 Product Type, Application and Specification 7.5.2.1 Type I 7.5.2.2 Type II 7.5.3 Lockheed Martin Corporation Anti-Drone Sales, Revenue, Price and Gross Margin (2011-2016) 7.5.4 Main Business/Business Overview 7.6 Israel Aerospace Industries 7.6.1 Company Basic Information, Manufacturing Base and Competitors 7.6.2 Million USD Product Type, Application and Specification 7.6.2.1 Type I 7.6.2.2 Type II 7.6.3 Israel Aerospace Industries Anti-Drone Sales, Revenue, Price and Gross Margin (2011-2016) 7.6.4 Main Business/Business Overview 7.7 Selex Es S. P. A. 7.7.1 Company Basic Information, Manufacturing Base and Competitors 7.7.2 Aerospace & Defense Product Type, Application and Specification 7.7.2.1 Type I 7.7.2.2 Type II 7.7.3 Selex Es S. P. A. Anti-Drone Sales, Revenue, Price and Gross Margin (2011-2016) 7.7.4 Main Business/Business Overview 7.8 Blighter Surveillance Systems 7.8.1 Company Basic Information, Manufacturing Base and Competitors 7.8.2 Product Type, Application and Specification 7.8.2.1 Type I 7.8.2.2 Type II 7.8.3 Blighter Surveillance Systems Anti-Drone Sales, Revenue, Price and Gross Margin (2011-2016) 7.8.4 Main Business/Business Overview 7.9 Droneshield 7.9.1 Company Basic Information, Manufacturing Base and Competitors 7.9.2 Product Type, Application and Specification 7.9.2.1 Type I 7.9.2.2 Type II 7.9.3 Droneshield Anti-Drone Sales, Revenue, Price and Gross Margin (2011-2016) 7.9.4 Main Business/Business Overview 7.10 Raytheon Company 7.10.1 Company Basic Information, Manufacturing Base and Competitors 7.10.2 Product Type, Application and Specification 7.10.2.1 Type I 7.10.2.2 Type II 7.10.3 Raytheon Company Anti-Drone Sales, Revenue, Price and Gross Margin (2011-2016) 7.10.4 Main Business/Business Overview For more information, please visit https://www.wiseguyreports.com/sample-request/736043-global-anti-drone-sales-market-report-2016


News Article | November 3, 2016
Site: www.newsmaker.com.au

This report studies Anti-Drone in Global market, especially in North America, Europe, China, Japan, Southeast Asia and India, with production, revenue, consumption, import and export in these regions, from 2011 to 2015, and forecast to 2021. This report focuses on top manufacturers in global market, with production, price, revenue and market share for each manufacturer, covering The Boeing Company Airbus Group SE SAAB AB Thales Group Lockheed Martin Corporation Israel Aerospace Industries Selex Es S. P. A. Blighter Surveillance Systems Droneshield Raytheon Company By types, the market can be split into Detection System Detection and Disruption Type III By Application, the market can be split into Military and Defense Commercial Homeland Security By Regions, this report covers (we can add the regions/countries as you want) North America China Europe Southeast Asia Japan India View Full Report With Complete TOC, List Of Figure and Table: http://globalqyresearch.com/global-anti-drone-market-professional-survey-report-2016 Global Anti-Drone Market Professional Survey Report 2016 1 Industry Overview of Anti-Drone 1.1 Definition and Specifications of Anti-Drone 1.1.1 Definition of Anti-Drone 1.1.2 Specifications of Anti-Drone 1.2 Classification of Anti-Drone 1.2.1 Detection System 1.2.2 Detection and Disruption 1.2.3 Type III 1.3 Applications of Anti-Drone 1.3.1 Military and Defense 1.3.2 Commercial 1.3.3 Homeland Security 1.4 Market Segment by Regions 1.4.1 North America 1.4.2 China 1.4.3 Europe 1.4.4 Southeast Asia 1.4.5 Japan 1.4.6 India 8 Major Manufacturers Analysis of Anti-Drone 8.1 The Boeing Company 8.1.1 Company Profile 8.1.2 Product Picture and Specifications 8.1.2.1 Type I 8.1.2.2 Type II 8.1.2.3 Type III 8.1.3 The Boeing Company 2015 Anti-Drone Sales, Ex-factory Price, Revenue, Gross Margin Analysis 8.1.4 The Boeing Company 2015 Anti-Drone Business Region Distribution Analysis 8.2 Airbus Group SE 8.2.1 Company Profile 8.2.2 Product Picture and Specifications 8.2.2.1 Type I 8.2.2.2 Type II 8.2.2.3 Type III 8.2.3 Airbus Group SE 2015 Anti-Drone Sales, Ex-factory Price, Revenue, Gross Margin Analysis 8.2.4 Airbus Group SE 2015 Anti-Drone Business Region Distribution Analysis 8.3 SAAB AB 8.3.1 Company Profile 8.3.2 Product Picture and Specifications 8.3.2.1 Type I 8.3.2.2 Type II 8.3.2.3 Type III 8.3.3 SAAB AB 2015 Anti-Drone Sales, Ex-factory Price, Revenue, Gross Margin Analysis 8.3.4 SAAB AB 2015 Anti-Drone Business Region Distribution Analysis 8.4 Thales Group 8.4.1 Company Profile 8.4.2 Product Picture and Specifications 8.4.2.1 Type I 8.4.2.2 Type II 8.4.2.3 Type III 8.4.3 Thales Group 2015 Anti-Drone Sales, Ex-factory Price, Revenue, Gross Margin Analysis 8.4.4 Thales Group 2015 Anti-Drone Business Region Distribution Analysis 8.5 Lockheed Martin Corporation 8.5.1 Company Profile 8.5.2 Product Picture and Specifications 8.5.2.1 Type I 8.5.2.2 Type II 8.5.2.3 Type III 8.5.3 Lockheed Martin Corporation 2015 Anti-Drone Sales, Ex-factory Price, Revenue, Gross Margin Analysis 8.5.4 Lockheed Martin Corporation 2015 Anti-Drone Business Region Distribution Analysis 8.6 Israel Aerospace Industries 8.6.1 Company Profile 8.6.2 Product Picture and Specifications 8.6.2.1 Type I 8.6.2.2 Type II 8.6.2.3 Type III 8.6.3 Israel Aerospace Industries 2015 Anti-Drone Sales, Ex-factory Price, Revenue, Gross Margin Analysis 8.6.4 Israel Aerospace Industries 2015 Anti-Drone Business Region Distribution Analysis 8.7 Selex Es S. P. A. 8.7.1 Company Profile 8.7.2 Product Picture and Specifications 8.7.2.1 Type I 8.7.2.2 Type II 8.7.2.3 Type III 8.7.3 Selex Es S. P. A. 2015 Anti-Drone Sales, Ex-factory Price, Revenue, Gross Margin Analysis 8.7.4 Selex Es S. P. A. 2015 Anti-Drone Business Region Distribution Analysis Global QYResearch is the one spot destination for all your research needs. Global QYResearch holds the repository of quality research reports from numerous publishers across the globe. Our inventory of research reports caters to various industry verticals including Healthcare, Information and Communication Technology (ICT), Technology and Media, Chemicals, Materials, Energy, Heavy Industry, etc. With the complete information about the publishers and the industries they cater to for developing market research reports, we help our clients in making purchase decision by understanding their requirements and suggesting best possible collection matching their needs.


Yue Z.,CAS Shanghai Institute of Technical Physics | Yue Z.,System Detection | Li F.-M.,CAS Shanghai Institute of Technical Physics | Li F.-M.,System Detection
Journal of Applied Optics | Year: 2014

Based on the characteristics that the infrared polarization image can restrain background noise greatly, and can be more sensitive to target edge information, a polarization image fusion algorithm based on wavelet transform is proposed. It is mainly used in image fusion between the infrared radiation intensity image and the polarization degree image in order to increase the amount of information of the image. First, wavelet transform can make different wavelet scaling decomposition in each involved image respectively, and get the wavelet coefficients of each scale. Second, it uses the method of neighborhood average gradient on each scaling wavelet coefficients to get each scaling wavelet fusion coefficients. Last, it makes image reconstruction based on wavelet transform to get fused image. The comparison between the images and fused images shows that this method can keep image clarity of the radiation intensity image, as well as highlight the edge and contour information. Compared to the radiation intensity image, the average gradient of fused images increases by 112%, while compared to the polarization degree image, the standard deviation of fused images increases by 151%, and the information entropy of fused images increases by 38%.


Ballarotti M.G.,National Institute for Space Research | Medeiros C.,National Institute for Space Research | Saba M.M.F.,National Institute for Space Research | Schulz W.,System Detection | Pinto Jr. O.,National Institute for Space Research
Journal of Geophysical Research: Atmospheres | Year: 2012

This paper presents some parameters of negative cloud-to-ground lightning flashes in terms of frequency distribution. All data are based on so-called "accurate-stroke-count studies" from different climatological regions in the world and were already published in the literature with the exception of our measurements. We used GPS synchronized data from two digital high-speed cameras (at 1-8,000 frames/sec). The parameters considered in this study are: (1) continuing current duration, (2) time intervals between strokes, (3) number of strokes per flash and (4) total flash duration. The analysis includes Berger's data of Monte San Salvatore (Switzerland), which is the basis for lightning protection standards. The comparison suggests that despite of overall agreement of those parameters that some of them, currently used in protection standards, should be revised in order to be more realistic. © 2012 by the American Geophysical Union.


Sun S.,System Detection | Wang Q.,System Detection | Zhao F.,System Detection | Chen W.,System Detection | Li Z.,System Detection
PLoS ONE | Year: 2011

Influenza virus typically alters protein glycosylation in order to escape immune pressure from hosts and hence to facilitate survival in different host environments. In this study, the patterns and conservation of glycosylation sites on HA and NA of influenza A/H1N1 viruses isolated from various hosts at different time periods were systematically analyzed, by employing a new strategy combining genome-based glycosylation site prediction and 3D modeling of glycoprotein structures, for elucidation of the modes and laws of glycosylation site alteration in the evolution of influenza A/H1N1 viruses. The results showed that influenza H1N1 viruses underwent different alterations of protein glycosylation in different hosts. Two alternative modes of glycosylation site alteration were involved in the evolution of human influenza virus: One was an increase in glycosylation site numbers, which mainly occurred with high frequency in the early stages of evolution. The other was a change in the positional conversion of the glycosylation sites, which was the dominating mode with relatively low frequency in the later evolutionary stages. The mechanisms and possibly biological functions of glycosylation site alteration for the evolution of influenza A/H1N1 viruses were also discussed. Importantly, the significant role of positional alteration of glycosylation sites in the host adaptation of influenza virus was elucidated. Although the results still need to be supported by experimental data, the information here may provide some constructive suggestions for research into the glycosylation of influenza viruses as well as even the design of surveillance and the production of viral vaccines. © 2011 Sun et al.


Patent
System Detection | Date: 2011-04-20

The present disclosure provides an optical device for selecting specific matter, such as plant matter. The device comprises a light source for emitting light having at least (3) wavelengths and for generating a combined beam of light having the at least 3 wavelengths. The device further comprises an optical element for directing a plurality of light beams towards matter including the specific matter. The optical element has first surface portions through which in use the plurality of component light beams are directed to the matter including the specific matter. Each component light beam is directed through a respective first surface portion that has an optical property that is selected so that light intensity differences between the component light beams are reduced. The optical device also comprises an optical filter for filtering reflected component light beams such that an intensity of light is reduced in a wavelengths range outside one or more wavelengths ranges that include the at least three wavelengths. Further, the optical device comprises a detector for detecting the reflected component light beams.

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