Articles de revues : « LIGHTNING ROD EFFECT »

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Kongnok, Rungphet, Thanakorn Pummaitong et Boonyang Plangklang. « Five-Year Performance of an ESE Lightning Protection System for a Large Scale PV Power Plant in Thailand ». Symmetry 13, n^o 11 (6 novembre 2021) : 2106. http://dx.doi.org/10.3390/sym13112106.

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This article presents a five-year performance review of an early streamer emission (ESE) air terminal lightning protection system for a large scale PV power plant in Thailand. The comparison effect of a Franklin lightning protection system and the ESE lightning protection system was analyzed for the PV power plant. The ESE lightning protection system was selected to be implemented in the PV power plant. The capacity of the PV power plant studied was 8 MWp on an area of 150,000 square meters in the Nong Ya Plong district, Phetchaburi province, Western Thailand. A Franklin lightning rod type was also designed to be implemented in this PV power plant. The Franklin lightning rod type comprised 122 pieces but the ESE lightning rod type consisted of only 11 pieces. The conceptual design of the Franklin rod type followed the standard of the Council of Engineers, Thailand, and the ESE lightning rod type followed the NFC17102 standard of France. The estimated cost of installation was a key comparison to select the lightning protection system; the total installation cost of the Franklin lightning rod type was USD 197,363.80 and the ESE lightning rod type was USD 44,338.06. The lightning system was applied to the lightning arrester in the power plant to provide good protection, in which the balance of the pole to the mounting position is required to optimize the system performance. The result of the simulation also showed that the shading effects of the Franklin rod type were greater than the ESE rod type. The installation cost of the Franklin lightning rod type was 4.45 times more expensive than the ESE lightning rod type. Therefore, the ESE lightning protection system was selected to be implemented in the PV power plant. From the recorded data of the five-year performance of the ESE lightning protection system (2016–2020), there were three occurrences of a lightning strike on the PV power plant. The ESE lightning protection system effectively protected and prevented the lightning strike to the PV power plant. This study can help and support with the selection of a lightning system for the protection of large scale PV power plants in the future.

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WU, CHUANQI, SHIJUN XIE, FEI QI, BEIBEI LI, JUNBIAO WAN et JUNJIA HE. « EFFECT OF CORONA DISCHARGES ON THE INCEPTION OF POSITIVE UPWARD LEADER-STREAMER SYSTEM ». International Journal of Modern Physics B 27, n^o 28 (15 octobre 2013) : 1350165. http://dx.doi.org/10.1142/s0217979213501658.

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The critical-charge criterion of the stem-leader transition and the shielding effects of space charges on the streamer inception are two most contested issues on the inception of positive upward leader–streamer system (LSS). In this paper, a series of simulation experiments on the LSS inception were designed and carried out. A new critical-charge criterion in the range of 0.2–0.3 μC was proposed, and the previous criterion of 1.0 μC was proved to be harsh. The shielding effect of positive space charges on the streamer inception was verified directly by the experiment results. A theoretical formula for calculating the LSS inception voltage by the first-corona inception voltage was obtained. An appropriate first-corona inception time for getting an earlier LSS inception was proved to be existent. At last, the effects of the so-called improved lightning rods, such as the early streamer emission rod (ESE) and the controllable lightning rod (CL), were discussed, and it seemed that they would not help to extend the protective zones of the lightning rods.

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Khechekhouche, Ali. « The profile of the electric field on the earth discontinuity with a lightning conductor ». International Journal of Energetica 1, n^o 1 (18 décembre 2016) : 30. http://dx.doi.org/10.47238/ijeca.v1i1.8.

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In this paper, we present some results of investigations carried out in the electric field distribution of both horizontal and vertical lightning conductors in the case of discontinuous earth. The conductors may be situated as well as in the upper or the lower earth part. The electric field distribution was determined in the case of lightning conductor situated between the high voltage rod and the discontinuity (interface) and also in the case of high voltage rod situated between the lightning conductor and the discontinuity. In some situations the electric field distribution on the plan are smaller than defined by the electro-geometrical model. We attribute this result to the great field intensity at the discontinuity, which reduce the lightning conductor discharge capture effect. This is in concordance with the results concerning the electrical strength of such air gaps without lightning conductors.

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Xue, Mingshan, Wenfeng Wang, Junfei Ou, Fajun Wang et Wen Li. « Lightning rod effect in surface work function of semiconductor nanomaterials ». Applied Physics Letters 102, n^o 24 (17 juin 2013) : 243110. http://dx.doi.org/10.1063/1.4812238.

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Zhao, Guifeng, Kaifeng Xing, Yang Wang, Hui Qian et Meng Zhang. « Long Short-Term Memory Network for Predicting Wind-Induced Vibration Response of Lightning Rod Structures ». Buildings 13, n^o 5 (10 mai 2023) : 1256. http://dx.doi.org/10.3390/buildings13051256.

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Lightning rod structures are susceptible to wind loads due to their high slenderness ratio, high flexibility, and light weight. The wind-induced dynamic response of a lightning rod is critical for structural safety and reliability. The traditional methods for this response, including observation and simulation, focus on structural health monitoring (SHM), wind tunnel tests (WTTs), or fluid–structure interaction (FSI) simulations. However, all these approaches require considerable financial or computational investment. Additionally, problems such as data loss or data anomalies in the sensor monitoring process often occur during SHM or WTTs. This paper proposes an algorithm based on a long short-term memory (LSTM) network to predict the wind-induced dynamic response and to solve the problem of data link fracture caused by abnormal sensor data transmission or wind-induced damage to lightning rod structures under different wind speeds. The effectiveness and applicability of the proposed framework are demonstrated using actual monitoring data. Root-mean-squared error (RMSE), determination of coefficient (R2), variance accounted for (VAF), and the refined Willmott index (RWI) are employed as performance assessment indices for the proposed network model. At the same time, the random forest algorithm is adopted to analyze the correlation between the data of the different measurement points on the lightning rod structure. The results show that the LSTM method proposed in this paper has a high accuracy for the prediction of “missing” strain data during lightning rod strain monitoring under wind speeds of 15.81~31.62 m/s. Even under the extreme wind speed of 31.62 m/s, the values of RMSE, MAE, R2, RWI and VAF are 0.24053, 0.18213, 0.94539, 0.88172 and 0.94444, respectively, which are within the acceptable range. Using the data feature importance analysis function, it is found that the predicted strain data of the measurement point on the top part of the lightning rod structure are closely related to the test strain data of the two adjacent sections of the structure, and the effect of the test strain data of the measurement points that are far from the predicted measurement point can be ignored.

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Ermushev, A. V., Boris V. Mchedlishvili, V. A. Oleĭnikov et A. V. Petukhov. « Surface enhancement of local optical fields and the lightning-rod effect ». Quantum Electronics 23, n^o 5 (31 mai 1993) : 435–40. http://dx.doi.org/10.1070/qe1993v023n05abeh003090.

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Guo, Xiufeng, Ling Zhang, Ziyu Ji, Yue Gao, Zhaoxia Wang et Nian Zhao. « Three-Dimensional Simulation of Corona Discharge in a Double-Needle System during a Thunderstorm ». Atmosphere 14, n^o 5 (26 avril 2023) : 789. http://dx.doi.org/10.3390/atmos14050789.

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The effect of corona discharge from buildings or structures on the surrounding atmospheric electric field is very important in the measurement of urban atmospheric electric fields and the early warning of lightning. However, most previous studies were focused on independent buildings, with little research on three-dimensional building groups. Therefore, based on three-dimensional numerical simulation technology, this paper uses a double-needle system to simulate the characteristics of thunderstorm corona discharge from two equal-height buildings separated by a variable distance. The shielding effect of the double-needle system on the ground electric field is evaluated both with and without corona discharge, and the main conclusions are as follows: (1) The larger the distance between the two needles, the closer the peak corona current from each tip of the double-needle system is to that from an independent lightning rod at the same height. When the peak corona current from each tip of the double-needle system equals the peak corona current from an independent lightning rod at the same height to some level of approximation, the distance between the two needle systems is determined by the needle height at this time. (2) If the distance between the two needles is 0.1 m, the corona charge released by the double-needle system is almost equal to that released by an independent lightning rod. The corona charge released by the double-needle system is approximately twice as much as that released by an independent lightning rod when the distance between the two needles is increased to a certain value that increases with the needle height and the time of corona discharge. (3) The greater the value of the time of corona discharge, the stronger the shielding effect of the corona discharge on the ground electric field and the larger the shielding range, but the greater the value of the needle height, the smaller the shielding range. (4) Compared with the shielding effect with no corona discharge, that with corona discharge is greater, but the greater the value of the needle height, the less the enhancement. For example, for corona discharge with a time of 10 s, the needle height is 20 m, and the shielding range is ca. 70 m, which is 8.8 times that without corona discharge; however, for the needle height of 100 m, the shielding range is ca. 150 m, which is only 1.5 times that without corona discharge.

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Fukuoka, Norihiko, et Katsuaki Tanabe. « Lightning-Rod Effect of Plasmonic Field Enhancement on Hydrogen-Absorbing Transition Metals ». Nanomaterials 9, n^o 9 (30 août 2019) : 1235. http://dx.doi.org/10.3390/nano9091235.

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The plasmonic enhancement of electromagnetic field energy density at the sharp tips of nanoparticles or nanoscale surface roughnesses of hydrogen-absorbing transition metals, Pd, Ti, and Ni, is quantitatively investigated. A large degree of energy focusing is observed for these transition metals in the microwave region, even surpassing the enhancement for noble metals according to the conditions. Pd, for instance, exhibits peak field enhancement factors of 6000 and 2 × 108 in air for morphological aspect ratios of 10 and 100, respectively. Metal surfaces possibly contain such degrees of nano- or micro-scale native random roughnesses, and, therefore, the field enhancement effect may have been unknowingly produced in existing electrical and optical systems. In addition, for future devices under development, particularly in hydrogen-related applications, it is desirable to design and optimize the systems, including the choice of materials, structures, and operating conditions, by accounting for the plasmonic local energy enhancement effect around the metal surfaces.

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Urbieta, Mattin, Marc Barbry, Yao Zhang, Peter Koval, Daniel Sánchez-Portal, Nerea Zabala et Javier Aizpurua. « Atomic-Scale Lightning Rod Effect in Plasmonic Picocavities : A Classical View to a Quantum Effect ». ACS Nano 12, n^o 1 (11 janvier 2018) : 585–95. http://dx.doi.org/10.1021/acsnano.7b07401.

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Park, Jubong, Minseok Jo, Joonmyoung Lee, Seungjae Jung, Seonghyun Kim, Wootae Lee, Jungho Shin et Hyunsang Hwang. « Improved Switching Uniformity and Speed in Filament-Type RRAM Using Lightning Rod Effect ». IEEE Electron Device Letters 32, n^o 1 (janvier 2011) : 63–65. http://dx.doi.org/10.1109/led.2010.2084560.

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Wang, Xiaoxuan, Liang Zhao, Rui Zhao, Yixiang Zhou, Shiyu Wang, Xinyue Chi, Yuanyuan Xiong et al. « Enhanced electrocatalytic nitrogen reduction inspired by a lightning rod effect on urchin-like Co3O4 catalyst ». Chemical Engineering Journal 450 (décembre 2022) : 138316. http://dx.doi.org/10.1016/j.cej.2022.138316.

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Wang, Ting, Devin K. Brown et Xing Xie. « Operando Investigation of Locally Enhanced Electric Field Treatment (LEEFT) Harnessing Lightning-Rod Effect for Rapid Bacteria Inactivation ». Nano Letters 22, n^o 2 (4 novembre 2021) : 860–67. http://dx.doi.org/10.1021/acs.nanolett.1c02240.

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Khechekhouche, A., et D. Ben Attous. « Effect of earth discontinued to the electrical field distribution in rod-plane air gaps under lightning impulse ». Journal of Fundamental and Applied Sciences 8, n^o 3 (14 mars 2018) : 1054. http://dx.doi.org/10.4314/jfas.v8i3.21.

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Lee, Daeseok, Jeonghwan Song, Jiyong Woo, Jaesung Park, Sangsu Park, Euijun Cha, Sangheon Lee, Yunmo Koo, Kibong Moon et Hyunsang Hwang. « Optimized Lightning-Rod Effect to Overcome Trade-Off Between Switching Uniformity and On/Off Ratio in ReRAM ». IEEE Electron Device Letters 35, n^o 2 (février 2014) : 214–16. http://dx.doi.org/10.1109/led.2013.2295592.

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Zeng, Zhenxing, Xie Quan, Hongtao Yu, Shuo Chen et Shushen Zhang. « Nanoscale lightning rod effect in 3D carbon nitride nanoneedle : Enhanced charge collection and separation for efficient photocatalysis ». Journal of Catalysis 375 (juillet 2019) : 361–70. http://dx.doi.org/10.1016/j.jcat.2019.06.019.

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Mi, Yan, Quan Liu, Pan Li et Jin Xu. « Simulation of Carbon Nanotube-Based Enhancement of Cellular Electroporation under Nanosecond Pulsed Electric Fields ». BioMed Research International 2019 (16 décembre 2019) : 1–10. http://dx.doi.org/10.1155/2019/9654583.

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Carbon nanotubes (CNTs) with large aspect ratios and excellent electrical properties can enhance the killing effect of nanosecond pulsed electric fields (nsPEFs) on tumor cells, which can improve the electrical safety of nsPEF during tumor treatment. To study the mechanism of the CNT-enhanced killing effect of a nsPEF on tumor cells, a spherical, single-cell, five-layer dielectric model containing randomly distributed CNTs was established using COMSOL and MATLAB, and then, the effects of the addition of CNTs on the electric field and the electroporation effect on the inner and outer membranes were analyzed. The results showed that CNTs can enhance the local electric field strength due to a lightning rod effect, and the closer the CNT tip was to the cell, the greater the electric field strength was around the cell. This increase in the local electric field strength near the cells enhanced the electroporation effects, including pore density, pore area, and pore flux. The simulation results presented in this paper provide theoretical guidance for subsequent development of nsPEF combined with CNTs for use in both cell and tissue experiments.

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Le Nader, V., J. Y. Mevellec, T. Minea et G. Louarn. « Gold Nanoparticles as Probes for Nano-Raman Spectroscopy : Preliminary Experimental Results and Modeling ». International Journal of Optics 2012 (2012) : 1–8. http://dx.doi.org/10.1155/2012/591083.

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This paper presents an effective Tip-Enhanced Raman Spectrometer (TERS) in backscattering reflection configuration. It combines a tip-probe nanopositioning system with Raman spectroscope. Specific tips were processed by anchoring gold nanoparticles on the apex of tapered optical fibers, prepared by an improved chemical etching method. Hence, it is possible to expose a very small area of the sample (~20 nm2) to the very strong local electromagnetic field generated by the lightning rod effect. This experimental configuration was modelled and optimised using the finite element method, which takes into account electromagnetic effects as well as the plasmon resonance. Finally, TERS measurements on single-wall carbon nanotubes were successfully performed. These results confirm the high Raman scattering enhancement predicted by the modelling, induced by our new nano-Raman device.

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HUTTUNEN, MIKKO J., JOUNI MÄKITALO et MARTTI KAURANEN. « POLARIZATION-CONTROLLABLE WINGED NANOCONE TIP ANTENNA ». Journal of Nonlinear Optical Physics & ; Materials 20, n^o 04 (décembre 2011) : 415–25. http://dx.doi.org/10.1142/s0218863511006212.

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We propose winged metal nanocone optical antennas for efficient coupling of far-field radiation into the near-field of sharp metal tips. Unlike normal sharp metal tips, the winged nanocones require no oscillating field along the tip axis for the excitation of the tips. We calculate extinction spectra and local-field enhancements for single and winged gold nanocones and show that the field enhancements in the tips of the winged cones are due to a combination of particle plasmon resonances and a lightning-rod effect. We also propose that the winged nanocones could be used for optical far-field background suppression for tip-enhanced microscopy.

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Lebedev, S. V. « The resilience of monarchies in the Greater Middle East : The lightning rod effect, crackdown on protest, and patrimonial links ». Humanities and Social Sciences. Bulletin of the Financial University 12, n^o 6 (25 février 2023) : 103–8. http://dx.doi.org/10.26794/2226-7867-2022-12-6-103-108.

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The paper examines the factors that allowed the Greater Middle East monarchies to survive the protests known as the “Arab Spring”. The author considers the popular argument in scientific and media-political discourse about the culturally conditioned legitimacy of the Middle Eastern monarchies, and also presents several cases of successful anti-monarchist revolutions in the region (Egypt, Tunisia, Iraq, Iran, Libya and Yemen). In addition, the work develops the idea that it can conditionally divide all the monarchies of the Greater Middle East into two types: individualistic and clan. The paper shows that patrimonial ties, which have been carefully built over several decades, are an important element in the stability of monarchies.

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Gong, Jian’gang, Zhouyou Lin, Yangyong Xu, Shen Zhao et Qiang Zhang. « The Performance of Lightning Rod Arrester and Its Effect on the Top Potential of Tower for 500 kV Transmission System ». Journal of Power and Energy Engineering 02, n^o 11 (2014) : 19–23. http://dx.doi.org/10.4236/jpee.2014.211003.

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Pradhan, S. S., et A. Sarkar. « Pearl – A Nano-Composite & ; Natural Super Dielectric ». Journal of Biomimetics, Biomaterials and Tissue Engineering 11 (septembre 2011) : 1–12. http://dx.doi.org/10.4028/www.scientific.net/jbbte.11.1.

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Pearl is a bio-originated valuable natural gem and it is also cultivated or harvested for jewellery. In this paper, the material aspects of pearl have been investigated experimentally and it has been found that it has a very high static dielectric constant ~ 105. The functional nature of the material is also established in this work. The beautiful lustre of natural pearl is explained by nano-optics and the layered structure of the material. The origin of super-dielectric nature of pearl has been explained by lightning rod effect (LRE) that causes ultra-high polarization of the dielectric background. The LRE is due to the presence of very small sized nano-particles in the natural pearl. Its electrical conductivity is mostly ionic, only less than 10% of the total conductivity is electronic. The scope of tailoring of its electro-activity has been probed.

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Ren, Pinyun, Weichang Zhou, Xianpei Ren, Xingang Zhang, Bin Sun, Yuanfu Chen, Qi Zheng, Jun Li et Wanli Zhang. « Improved surface-enhanced Raman scattering (SERS) sensitivity to molybdenum oxide nanosheets via the lightning rod effect with application in detecting methylene blue ». Nanotechnology 31, n^o 22 (13 mars 2020) : 224002. http://dx.doi.org/10.1088/1361-6528/ab758b.

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Jiang, Chuan, et Jianzhong Shi. « The Surface-Enhanced Raman Spectroscopy Platform Based on Raspberry-Like Au@Au Nanoparticles for Sensitive Estriol Detection ». Science of Advanced Materials 14, n^o 6 (1 juin 2022) : 1018–23. http://dx.doi.org/10.1166/sam.2022.4303.

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As an important secretion during pregnancy, estriol is closely related to fetal growth. Thus, it is very important to develop ultrasensitive and non-invasive detecting approaches for monitoring the concentration of estriol. Here, we provide a non-invasive, fast and sensitive Surface-enhanced Raman Spectroscopy (SERS) detection platform that consist of spiky Au@Au nanoparticles (NPs) for fingerprint analysis of estriol. Based on the “lightning rod effect” and high scattering performance of the composite Au@Au structure, the detection sensitivity can be improved. Even so, the lower scattering cross section of estriol makes it impossible to be directly detected. Considering that, the azo reaction strategy is introduced into our system to improve the molecular scattering cross section, further enhance the detection sensitivity of estriol by forming the N=N bond. As a result, estriol can be detected to nanomolar level, which fully meets the detection requirements of estriol’s actual physiological range. We believe that this work not only provides an effective scope for the hypersensitive detection of estriol, but also provides an idea for improving the scattering cross section of biomarkers by using the analyte manipulating approach, which is very important for the monitoring of human health indicators.

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Tian, Yue, Qingqiang Cui, Hui Ma, Anxin Jiao, Chang Wang, Mengya Zhang, Linqi Zheng et al. « Extra electric field-enhanced lightning rod effect in pine needle-like Au microarrays for boosting direct plasmon-driven photoelectrochemical hydrogenation reactions via in-situ SERS monitoring ». Applied Surface Science 578 (mars 2022) : 152100. http://dx.doi.org/10.1016/j.apsusc.2021.152100.

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Spector, Bert A. « Executive incentives as an instrument of leadership – Says who ? » Leadership 14, n^o 3 (30 septembre 2016) : 347–62. http://dx.doi.org/10.1177/1742715016667322.

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There is currently wide consensus concerning the notion that corporations can and should call on executive incentives, particularly cash bonuses and stock options, to shape executive behaviors and enhance company performance. To be sure, much controversy surrounds the implementation of such incentives, but the lightning rod is typically the matter of how much, not the use of incentives themselves. Contemporary research, by and large, seeks to fine-tune an existing paradigm rather than probe its underlying assumptions. This article calls on the methodology of history to probe the underlying assumptions and construction of executive incentives in order to ask those fundamental questions. By exploring the work of General Motors president Alfred Sloan and McKinsey & Company consultant Arch Patton, both prime movers of the widespread use of such incentives, the article notes that their beliefs were an outgrowth of a particular historical context. The assumptions that emerged as a result of that context have since become embedded into our collective institutional consciousness and have impacted society far beyond the borders of corporations; helping to support an ever-widening gulf between the top 1% of society and the remainder. A reconsideration of the underlying assumptions is encouraged. The impact on organizational performance would be either negligible or positive; and the effect on economic distribution in the company and the host society would be profound. Abandoning the outmoded notion of executive inventive, in other words, would be an act of true leadership.

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Songsang, Arnon, Nattachote Rugthaichareoncheep et Att Phayomhom. « Grounding Design Improvement to Reduce Back Flashover Rate of 69 kV Subtransmission Line in Power’s Distribution System ». Applied Mechanics and Materials 781 (août 2015) : 250–53. http://dx.doi.org/10.4028/www.scientific.net/amm.781.250.

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This paper presents the grounding design improvement to reduce back flashover rate from the lightning of distribution system. The Purpose to reduce effects of lightning overvoltage from back flashover. And study analysis of the condition effects of lightning performance of 69 kV on Metropolitan Electricity Authority (MEA)’s distribution system of Thailand. The technique objective function is an attachment the external ground wire connected between the overhead ground wires and a ground rod for reduce back flashover. Back flashover is one of the major causes of sustained interruption data. Occurs when the amplitude of lightning overvoltage is more than the limit of insulator strings specification. Then generated flashover on insulator skin and induces the voltage line. This paper simulation with Alternative Transient Program-Electromagnetic Transient Program (ATP-EMTP) and analysis of lightning performance in terms evaluated pole top voltage and back flashover rate (BFOR). Result after installing the external grounding design system can reduce the effects of lightning and can improve the reliability in distribution system. And the grounding systems designed is can use for guide line to the features typically at locations subject to lightning damage.

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Siswanto, Agus, Junaedi Junaedi, Muhamad Soleh et Mudofar Baehaqi. « Analysis of Lightning Strike Effects on Crude Oil Storage Tank Protection System at PT. Pertamina Balongan Indramayu ». Mestro : Jurnal Teknik Mesin dan Elektro 4, n^o 01 (17 juin 2022) : 1–6. http://dx.doi.org/10.47685/mestro.v5i01.367.

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Main Gathering Station (MGS) Balongan Pertamina EP Asset 3 OGT is an industry engaged in the oil and gas sector by always paying attention to QHSE (Quality, Health, Safety and Environment) aspects. This industry is a national vital object categorized as a zone 1 and zone 2 hazardous area. There is a source of danger that has the potential to cause damage to equipment and people. The electrical installation used is a lightning protection system with reference to the NFPA 780-2017 standard concerning the Standard for the Installation of Lightning Protection Systems. The rolling sphere method is used to calculate the need for a lightning protection system. To calculate the need for a grounding electrode, a rod electrode grounding system is used. Construction MGS Balongan (Hazardous Construction) has a value of direct lightning strike frequency (Nd) of 0.03 lightning strikes per year with an equivalent area of building lightning strikes (Ae) of 1082.95 m2. The value (Ng) of the intensity of lightning strikes to the ground is 27.6 lightning strikes per km2 per year, the protection level is level II with a radius of 30 meters and the earth resistance value is 0.344 Ω. The design value of this calculation is in accordance with PUIL 2011 standards, namely it must be below 5Ω for the overall value of earth resistance.

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Sun, Hao, Jing Yang, Qilin Zhang, Lin Song, Haiyang Gao, Xiaoqin Jing, Guo Lin et Kang Yang. « Effects of Day/Night Factor on the Detection Performance of FY4A Lightning Mapping Imager in Hainan, China ». Remote Sensing 13, n^o 11 (4 juin 2021) : 2200. http://dx.doi.org/10.3390/rs13112200.

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In this study, the effect of day/night factor on the detection performance of the FY4A lightning mapping imager (LMI) is evaluated using the Bayesian theorem, and by comparing it to the measurements made by a ground-based low-frequency magnetic field lightning location system. Both the datasets were collected in the summers of 2019–2020 in Hainan, China. The results show that for the observed summer thunderstorms in Hainan, the daytime detection efficiencies of LMI (DELMI) were 20.41~35.53% lower than the nighttime DELMI. Compared to other space-based lightning sensors (lightning imaging sensors/optical transient detectors (LIS/OTD) and geostationary lightning mapper (GLM)), the detection performance of LMI is more significantly influenced by the day/night factor. The DELMI rapidly dropped within about four hours after sunrise while it increased before sunset. For the storms that formed at night and lasted for an entire day, the DELMI remained relatively low during the daytime, even as the thunderstorms intensified. The poor detection performance of LMI during daytime is probably because of the sunlight reflection by clouds and atmosphere, which results in larger background radiative energy density (RED) than that at night. During night, LMI captured the lightning signals well with low RED (8.38~10.63 μJ sr−1 m−2 nm−1). However, during daytime, signals with RED less than 77.12 μJ sr−1 m−2 nm−1 were filtered, thus lightning groups could rarely be identified by LMI, except those with extremely high RED. Due to the limitations of the Bayesian theorem, the obtained DE in this study was “relative” DE rather than “absolute” DE. To obtain the absolute DE of LMI, the total lightning density is necessary but can hardly be measured. Nonetheless, the results shown here clearly indicate the strong impact of day/night factor on the detection performance of LMI, and can be used to improve the design and post-processing method of LMI.

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Ullah, Irshad, Mohd Nor Ramdon Bin Bahrom, Muhammad Adeel Khan et Azhar Qazi. « An Experimental Study of Electromagnetic Field Propagation Due to Lightning Upward Leaders and Its Probability on Different Small-Scale Structures ». Energies 15, n^o 18 (9 septembre 2022) : 6597. http://dx.doi.org/10.3390/en15186597.

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In this paper, upward leader initiation and the probability of lightning flashes on different air terminal were analyzed in detail. With the growing global warming, lightning flash density has increased abruptly, especially in tropical countries. Upward leaders are the critical elements to be considered for defining comprehensive protective measures against lightning during thunderstorms. This article presents the lightning flashover phenomenon on scaled buildings with installed lightning rods. Moreover, the electric field and initialization of upward leaders from Lightning Air Terminals (LATs) were analyzed in detail using Ansys Maxwell as a simulation tool. For the experimental work, a high-voltage impulse generator was used. The air gap between the lightning rods and the top electrode was kept constant in all scaled structures. The purpose of using an identical air gap was to study the upward leader and its electric field for all structures. The effects of the upward leaders on the electric field plots are explained in detail and allowed the determination of the electric field’s intensity around each air terminal for the provided air gap between the tip of the rod and the top electrode. A low-cost lightning protection system was taken into account, as the economic crisis is worsening with time. A Franklin rod was used as the primary protection device for the initiation of the upward streamer. The experimental results were obtained in Malaysian weather conditions based on standard values of temperature and pressure. The study presented in this article shows that based on the experimental work, field plots were obtained for both the air insulation scenario and the condition when the upward leader was incepted. The simulation results showed a firm agreement with the measured values. Similarly, by upward leader inception, the strikes could be predicted accurately on every installed air terminal.

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Mulyandari, Hestin, et Luhur Sapto Pamungkas. « KARAKTERISTIK INFRASTRUKTUR RUMAH SUSUN DI KOTA YOGYAKARTA Kajian Terhadap Kenyamanan Penggunaan Infrastruktur Bangunan ». Jurnal Teknik Sipil dan Perencanaan 18, n^o 2 (15 octobre 2016) : 115–26. http://dx.doi.org/10.15294/jtsp.v18i2.7479.

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Infrastructure of flats is an important of building, that researchers would analyzed of flats infrastructure existing in the city of Yogyakarta, such as flat of Juminahan, Cokrodirjan and Rogoyudan. This study aims to analyze the infrastructure of three public apartments in Yogyakarta, based on the advantages and disadvantages of physical discomfort and un-safety of public apartments users. The analysis resulted some conclusions, such as (1) the material of infrastructure access to the building is adequate, but has dangerous ramp, (2) water infrastructure is adequate, (3) pipe of sewage is leaking, there are no sewage treatment, (4) Electrical Infrastructure is not good because the location of the electrical panel located on the outside of the building so prone to damage and the electricity network funneled into the building through the shaft and with the cable tray distributed throughout the room, (5) Condition of Fire Protections are much damaged, (6) The symbols of evacuation route path is incomplete, (7) Infrastructure of garbage disposal is not managed properly so that uncomfortable, (8) Lightning rod is adequate. Advantages and disadvantages of such infrastructure of public apartment may effect the users comfort, and this research will be useful for the next infrastructure planning.Kebutuhan Infrastruktur bangunan rumah susun menjadi hal penting. Sebelum merencanakan inovasi infrastruktur rumah susun di Kotamadya Yogyakarta, peneliti menganalisa kondisi eksisting infrastruktur dari tiga rumah susun sewa (rusunawa) di Kota Yogyakarta, yaitu dari karakteristik infrastruktur di Rusunawa Juminahan, Cokrodirjan dan Rogoyudan. Penelitian ini bertujuan menganalisa infrastruktur tiga rusunawa di Kotamadya Yogyakarta menurut keunggulan dan kelemahan fisik, ketidaknyamanan dan ketidakamanan pengguna rusunawa. Hasil analisa infrastruktur dari tiga rusunawa tersebut yaitu (1) material akses ke bangunan memadai, dan kemiringan ramp curam, (2) infrastruktur air bersih memadai, (3) infrastruktur air kotor, banyak pipa yang bocor, tidak terdapat pengolaha limbah, (4) Infrastruktur elektrikal tidak memadai karena letak panel listrik terdapat di luar bangunan sehingga rawan dengan kerusakan, (5) Kondisi sistem penanggulangan bahaya kebakaran banyak yang rusak, peralatannya hilang, (6) Jalur evakuasi tidak memadai karena simbol jalur evakuasinya tidak lengkap, (7) Infrastruktur persampahan shaft sampah dan penampungan sampah tidak dikelola dengan baik sehingga sampah berceceran dan menimbulkan bau yang tidak nyaman, (8) Penangkal petir cukup memadai sehingga bangunan aman terhadap petir. Analisa karakteristik tersebut berpengaruh terhadap kenyamanan penghuni rusunawa, dan dapat digunakan pada perencanaan infrastruktur rumah susun yang akan datang.

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Arienti, M. Cecilia, Steven G. Cumming, Meg A. Krawchuk et Stan Boutin. « Road network density correlated with increased lightning fire incidence in the Canadian western boreal forest ». International Journal of Wildland Fire 18, n^o 8 (2009) : 970. http://dx.doi.org/10.1071/wf08011.

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This paper quantifies the influence of anthropogenic linear disturbances on fire ignition frequency in the boreal forests of western Canada. Specifically, we tested if linear features increase the frequency of lightning fires, and whether this relationship is affected by spatial resolution. We considered fires that ignited between 1995 and 2002 within a ~67 000 km2 region of boreal mixed-wood forest in north-eastern Alberta where linear features are highly abundant and spatially heterogeneous. We constructed Poisson, Negative Binomial and Zero-Inflated Poisson models at two spatial resolutions (~10 000 and ~2400 ha), including covariates for linear feature densities, forest composition, weather–lightning indices and geography. We found a positive association between lightning fire frequency and road density; this association was consistent at both spatial resolutions. We suggest this occurs owing to increased availability of flammable fine fuels near roads. The effect was attributable neither to increased detectability of fires proximal to roads by human observers, nor to increased lightning strikes due to metallic infrastructure alongside roads or the topographic characteristics of road location. Our results suggest that, in the face of projected road developments in the region, the potential exists for important changes to the regional fire regime. Further research should elucidate the precise mechanisms in order to develop methods for mitigation.

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Katsuragi, Yukio, Yoshinori Aihara et Shinichi Watanabe. « An Experimental Study of Lightning Protection Effects to a Overhead Ground Wire by a Lightning Rod and Projection Rods ». IEEJ Transactions on Power and Energy 115, n^o 5 (1995) : 511–16. http://dx.doi.org/10.1541/ieejpes1990.115.5_511.

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Wu, Shaocheng, Linong Wang, Jiachen Gao, Cheng Xie, Lei Liu, Tingting Wang et Enwen Li. « Breakdown characteristics of combined air gaps under lightning impulse ». AIP Advances 12, n^o 3 (1 mars 2022) : 035024. http://dx.doi.org/10.1063/5.0084951.

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With the increase of both voltage level and the transmission capacity, more attention has been paid to the external insulation of transmission lines. As the main external insulation medium of transmission line, the air gap’s dielectric strength will change when there are floating conductors. In this paper, we established an experiment platform to study the effects of floating conductors, simulated by floating rod electrode, on breakdown voltage, breakdown time, electric field distribution and discharge physical process of long air gaps under lightning impulse. The results showed that the intervention of floating electrode reduced the breakdown voltage and breakdown time of long air gaps, and the position with the longest breakdown time was the same as the position with the lowest breakdown voltage. In addition, the intervention of floating electrode improved the spatial electric field and complexity of discharge physical process.

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Clemens, Roger, A. Wallace Hayes, Kalyana Sundram et Peter Pressman. « Palm oil and threats to a critically important food source ». Toxicology Research and Application 1 (1 janvier 2017) : 239784731769984. http://dx.doi.org/10.1177/2397847317699844.

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The oil palm, an ancient tropical tree species that originated in West Africa, has a history of centuries-long use both as a food and a medicine. Based on its higher saturated fatty acid composition, primarily palmitic acid, concerns have been flagged about its nutritional attributes. Elevation of low-density lipoprotein cholesterol effects of the associated palmitic acid is far less profound than animal sources of this fatty acid and is linked with multiple health benefits. Recently, the European Food Safety Authority raised issues about potential health risks of the chloropropanols, heat- or acid-induced food contaminants created during the refining of all edible oils, and some hydrolyzed proteins. Despite the fact that the levels of 3-monochloropropane1,2 diol and its glycidyl esters are generally <800 ppb and without demonstrated toxicological effects in humans, the chloropropanols in palm oil appear to be a lightning rod for global criticism. The toxicological data are reviewed and evaluated, and an approach for mitigation of the emerging challenge is suggested.

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Nikanovich, T. V., Yu V. Trofimov et M. I. Barkun. « The impact of LED lightning on the content of photosynthetic pigments in tomato leaves ». Vegetable crops of Russia, n^o 1 (5 mars 2021) : 117–20. http://dx.doi.org/10.18619/2072-9146-2021-1-117-120.

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Relevance and methods. We studied the influence of LED lighting of different spectral composition on the content of photosynthetic pigments in tomato leaves to identify the most optimal lighting option suitable for obtaining high-quality seedlings under controlled conditions. We used LED lamps in which the ratio of the photon flux density (PFD) of the orange-red band (607–694 nm) to the PFD of the blue band (400–495 nm) varied from 1 to 20. In this case, the proportion of the PFD in the range 580-607 nm ( yellow) ranged from 13 to 22%, and the fraction of photons in the range 495–580 nm (green) ranged from 18 to 38%. The research was carried out with two varieties of Belarusian tomato varieties, which differed in a number of morphobiological characteristics.Results. It was found that the use of LED lighting of different spectral composition had mainly an inhibitory effect on the biosynthesis of chlorophylls and carotenoids in the leaf tissue of plants. The decrease in the amount of pigments, in comparison with the control variant, reached 47-57%. It was revealed that under all studied lighting options, with the exception of conditions where the spectral ratio R / B ("red/blue") was 0.8, the value of the total inhibitory effect in the Cherry Coral variety was 1.2-1.7 times lower than that of the Zorka variety, which indicated a significantly lower susceptibility of the pigment fund of the former to LED lighting. The smallest inhibitory effect of the latter on the biosynthesis of photosynthetic pigments in both tomato varieties was established at a photon flux of 69.1 μmol/s, while the greatest, exceeding it by 3.0-3.1 times in the Zorka variety and 4.5-5.3 times for the Cherry Coral variety with a photon flux of 73.9 μmol/s.

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Ghoneim, Sherif, Ahdab Elmorshedy et Rabah Amer. « Transient impedance of grounding system with impulse superimposed sinewave ». ENP Engineering Science Journal 1, n^o 1 (22 juillet 2021) : 8–12. http://dx.doi.org/10.53907/enpesj.v1i1.7.

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Investigating the transient performance of grounding systems subject to lightning (impulse or impulse superimposed sinewave) is valuable for protecting the power system and maintaining the system operation. In this work, the grounding system's impedance is computed when an impulse superimposed sinewave is applied to the grounding grid's proposed lumped circuit and grounding system can be simulated as an inductance in series with resistance, and all of them are in parallel with capacitance based on Thione's assumption. Several variables were investigated to study their effects on the grounding system's behavior. The variables were the soil resistivity, soil permittivity, main wire length, grid conductor radius, grid side length, grid configurationand its mesh number. The grounding system configuration varied between square and rectangular shapes, which connects to the protecting rod via the main wire conductor. A 3.69 kA peak of impulse current was applied to avoid soil ionization. The results indicated the performance of the grounding system when subjecting to impulse current.

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Gora, Evan M., et Stephen P. Yanoviak. « Electrical properties of temperate forest trees : a review and quantitative comparison with vines ». Canadian Journal of Forest Research 45, n^o 3 (mars 2015) : 236–45. http://dx.doi.org/10.1139/cjfr-2014-0380.

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Trees form the terrestrial interface with the atmosphere in forested regions. The electrical properties of trees may influence their response to atmospheric conditions and potentially lethal phenomena (e.g., lightning). We review the literature describing electrical properties of trees and provide a tabular summary of the methods and goals of each study. We hypothesized that electrical resistivity varies consistently among species and between growth forms. We surveyed resistivity of eight tree and three vine species in Michigan and Kentucky, and we quantified resistivity over a moisture gradient for wood blocks of four tree species. Resistivity varied predictably with stem diameter and differed among species and growth forms. Specifically, resistivity of trees was approximately 200% higher than resistivity of vines, and resistivity of conifers was 135% higher than that of hardwoods. The regional comparison showed no difference in resistivity of red maple (Acer rubrum L.) and sugar maple (Acer saccharum Marsh.) between Michigan and Kentucky. These results, in combination with interspecific differences observed among wood blocks, suggest that there is a phylogenetic basis for variation in resistivity that reflects differences in anatomy and physiology. Our review and empirical survey provide a framework for studying the ecological effects of lightning in the context of the electrical properties of trees.

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Lieverse, R., M. Nielen, B. Uitdehaag, E. van Someren, J. Smit et W. Hoogendijk. « Double Blind Randomised Clinical Trial of Bright Light Therapy in Elderly Subjects with Nonseaonal Major Depressive Disorder ». European Psychiatry 24, S1 (janvier 2009) : 1. http://dx.doi.org/10.1016/s0924-9338(09)70553-x.

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Background:The cause of depression is largely unknown, but several studies point to disturbances of biological rhythmicity. The functioning of the suprachiasmatic nucleus (SCN) is impaired, as evidenced by an increased prevalence of day-night rhythm perturbations, such as sleeping disorders. Moreover, the inhibitory SCN neurons on the hypothalamus-pituitary adrenocortical axis (HPA-axis) have decreased activity and HPA-activity is enhanced, when compared to non-depressed elderly. Using bright light therapy (BLT) the SCN can be stimulated. In addition, the beneficial effects of BLT on seasonal depression are well accepted. BLT is a potentially safe, nonexpensive and well accepted treatment option. But the current literature on BLT for depression is inconclusive.Methods/design:RCT (ClinicalTrials.gov identifier: NCT00332670) in 89 subjects, of 60 years and older with a diagnosis of major depressive disorder. After inclusion subjects were randomly allocated to the active (BLT) vs. placebo (dim red light) condition. just before the start of light therapy, after completion of three weeks therapy period, and three weeks thereafter several endocrinological, psychophysiological, psychometrically, neuropsychological measures are performed:Results:Main effect analyses on HADRS-17 scores revealed significant antidepressant effects from BLT. Primary results will be presented.Discussion:BLT reduces nonseasonal depression in elderly patients. Additional lightning may easily be implemented in the homes of patients to serve as add-on treatment to antidepressants or as a stand-alone treatment in elderly depressed patients. Our data support the role of a dysfunctional biological clock in depressed elderly subjects, such a finding may guide further development of novel chronobiological oriented treatment strategies.

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Suwanasri, Cattareeya, Surapol Saribut, Thanapong Suwanasri et Rattanakorn Phadungthin. « Risk Analysis Using Failure Modes, Effects, and Criticality Analysis for Transmission Network Assets ». Energies 14, n^o 4 (12 février 2021) : 977. http://dx.doi.org/10.3390/en14040977.

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In this paper, we apply the Failure Modes, Effects, and Criticality Analysis (FMECA) approach to the criticality and risk analysis of the efficiency, safety/reliability, environment, and financial criteria of the high voltage transmission line. In the efficiency analysis, the weighting-scoring method and analytical hierarchy process are applied to obtain the line renovation index, which is interpreted as efficiency severity. The safety/reliability severity relates to the system impacts are caused by failure of the equipment and the system. The environmental severity takes social impacts and pollution into consideration. The financial severity involves the cost of spare parts and maintenance costs, which are interpreted as the financial severity of the lines. Twenty practical transmission lines in Thailand with actual data for 115, 230, and 500 kV were studied. The transmission line components are divided into eight components including the conductor, conductor accessories, insulator, steel structure, foundation, lightning protection system, tower accessories, and right-of-way. The severity and criticality of the components and transmission lines are analyzed and plotted in criticality matrices based on four criteria. This criticality matrix is presented at four different levels including very low, low, medium, and high risk, as represented by four color bands: green, yellow, orange, and red, respectively. The results show that three 115 kV lines are the first priority for short-term reconstruction planning because of their unacceptable condition and high risk in terms of safety/reliability and financing. Recommendations for maintenance strategy and risk mitigation are proposed for the utility according to the utility’s actual criticality. Ultimately, maintenance planning of the transmission system can be effectively managed with higher reliability, a lower risk of failure, and a lower cost of maintenance.

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Kitazaki, Michiteru. « Human temporal coordination of visual and auditory events in virtual reality ». Seeing and Perceiving 25 (2012) : 31. http://dx.doi.org/10.1163/187847612x646532.

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Since the speed of sound is much slower than light, we sometimes hear a sound later than an accompanying light event (e.g., thunder and lightning at a far distance). However, Sugita and Suzuki (2003) reported that our brain coordinates a sound and its accompanying light to be perceived simultaneously within 20 m distance. Thus, the light accompanied with physically delayed sound is perceived simultaneously with the sound in near field. We aimed to test if this sound–light coordination occurs in a virtual-reality environment and investigate effects of binocular disparity and motion parallax. Six naive participants observed visual stimuli on a 120-inch screen in a darkroom and heard auditory stimuli from a headphone. A ball was presented in a textured corridor and its distance from the participant was varied from 3–20 m. The ball changed to be in red before or after a short (10 ms) white noise (time difference: −120, −60, −30, 0, +30, +60, +120 ms), and participants judged temporal order of the color-change and the sound. We varied visual depth cues (binocular disparity and motion parallax) in the virtual-reality environment, and measured the physical delay at which visual and auditory events were perceived simultaneously. In terms of the results, we did not find sound–light coordination without binocular disparity or motion parallax, but found it with both cues. These results suggest that binocular disparity and motion parallax are effective for sound–light coordination in virtual-reality environment, and richness of depth cues are important for the coordination.

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Koffi, B., S. Szopa, A. Cozic, D. Hauglustaine et P. van Velthoven. « Present and future impact of aircraft, road traffic and shipping emissions on global tropospheric ozone ». Atmospheric Chemistry and Physics Discussions 10, n^o 6 (28 juin 2010) : 15755–809. http://dx.doi.org/10.5194/acpd-10-15755-2010.

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Abstract. In this study, the LMDz-INCA climate-chemistry model and up-to-date global emission inventories are used to investigate the "present" (2000) and future (2050) impacts of transport emissions (road traffic, shipping and aircraft) on global tropospheric ozone. For the first time, both impacts of emissions and climate changes on transport-induced ozone are investigated. The 2000 transport emissions are shown to mainly affect ozone in the Northern Hemisphere, with a maximum increase of the tropospheric column of up to 5 DU, from the South-Eastern US to Central Europe. The impact is dominated by road traffic in the middle and upper troposphere, north of 40° S, and by shipping in the northern lower troposphere, over oceanic regions. A strong reduction of road emissions and amoderate (B1 scenario) to high (A1B scenario) increase of the ship and aircraft emissions are expected by the year 2050. As a consequence, LMDz-INCA simulations predict a drastic decrease in the impact of road emissions, whereas aviation would become the major transport perturbation on tropospheric ozone, even in the case of avery optimistic aircraft mitigation scenario. The A1B emission scenario leads to an increase of the impact of transport on zonal mean ozone concentrations in 2050 by up to +30% and +50%, in the Northern and Southern Hemispheres, respectively. Despite asimilar total amount of global NOx emissions by the various transport sectors compared to 2000, the overall impact on the tropospheric ozone column is increased everywhere in 2050, due to a sectoral shift in the emissions of the respective transport modes. On the opposite, the B1 mitigation scenario leads to asignificant reduction (by roughly 50%) of the ozone perturbation throughout the troposphere compared to 2000. Considering climate change, and according to scenario A1B, a decrease of the O3 tropospheric burden is simulated by 2050 due to climate change (−1.2%), whereas an increase of ozone of up to 2% is calculated in the upper troposphere in the inter-tropical zone, due to enhanced lightning activity. A global impact of similar magnitude is simulated for the transport-induced ozone burden perturbation (−1.6%). As a result, the future increase in global ozone due to changes in anthropogenic emissions is lowered by 12% and by 4%, for the background and the transport-induced ozone, respectively. However, positive and negative climate effects are obtained on ozone, depending on the season, region and altitude, with an increase of the transport-induced ozone perturbation (+0.4 DU) in the already most affected area of Northern Hemisphere.

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Koffi, B., S. Szopa, A. Cozic, D. Hauglustaine et P. van Velthoven. « Present and future impact of aircraft, road traffic and shipping emissions on global tropospheric ozone ». Atmospheric Chemistry and Physics 10, n^o 23 (9 décembre 2010) : 11681–705. http://dx.doi.org/10.5194/acp-10-11681-2010.

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Abstract. In this study, the LMDz-INCA climate-chemistry model and up-to-date global emission inventories are used to investigate the "present" (2000) and future (2050) impacts of transport emissions (road traffic, shipping and aircraft) on global tropospheric ozone. For the first time, both impacts of emissions and climate changes on transport-induced ozone are investigated. The 2000 transport emissions are shown to mainly affect ozone in the Northern Hemisphere, with a maximum increase of the tropospheric column of up to 5 DU, from the South-eastern US to Central Europe. The impact is dominated by road traffic in the middle and upper troposphere, North of 40° S, and by shipping in the northern lower troposphere, over oceanic regions. A strong reduction of road emissions and a moderate (B1 scenario) to high (A1B scenario) increase of the ship and aircraft emissions are projected by the year 2050. As a consequence, LMDz-INCA simulations predict a drastic decrease in the impact of road emissions, whereas aviation would become the major transport perturbation on tropospheric ozone, even in the case of a very optimistic aircraft mitigation scenario. The A1B emission scenario leads to an increase of the impact of transport on zonal mean ozone concentrations in 2050 by up to +30% and +50%, in the Northern and Southern Hemispheres, respectively. Despite a similar total amount of global NOx emissions by the various transport sectors compared to 2000, the overall impact on the tropospheric ozone column is increased everywhere in 2050, due to a sectoral shift in the emissions of the respective transport modes. On the opposite, the B1 mitigation scenario leads to a significant reduction (by roughly 50%) of the ozone perturbation throughout the troposphere compared to 2000. Considering climate change, and according to scenario A1B, a decrease of the O3 tropospheric burden is simulated by 2050 due to climate change (−1.2%), whereas an increase of ozone of up to 2% is calculated in the upper troposphere in the inter-tropical zone, due to enhanced lightning activity. A global impact of similar magnitude is simulated for the transport-induced ozone burden perturbation (−1.6%). As a result, the future increase in global ozone due to changes in anthropogenic emissions is lowered by 12% and by 4%, for the background and the transport-induced ozone, respectively. However, positive and negative climate effects are obtained on ozone, depending on the season, region and altitude, with an increase of the transport-induced ozone perturbation (+0.4 DU) in the already most affected area of Northern Hemisphere.

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Stanislavchuk, O., O. Gornostaj, N. Slobodianyk et V. Tokars'ka. « DANGERS MONITORING IN SECONDARY EDUCATION INSTITUTIONS ». Bulletin of Lviv State University of Life Safety 20 (23 janvier 2020) : 64–73. http://dx.doi.org/10.32447/20784643.20.2019.09.

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Creating a safe environment in schools is an extremely important task that requires a lot of attention. Peculiarity of such educational institution is: - availability of premises for various purposes (classrooms, classrooms for such subjects as chemistry and physics, workshops for labor training with tools, materials, sewing machines, sports and assembly hall, dining room, kitchen). - group stay in one building of different children age groups at the same time. - institutions become the venue for various events – fairs, concerts, meetings, sports competitions. The legislation of Ukraine states that all institution employees, as well as students, should be taught the safe be-havior rules. It has been researched that child traumatism makes up about 26% of the total, including 12-16% at school. It is found that not all educational staff have an idea of the potential dangers real number that could endanger both their lives and their health and their students as well. The main causes of school traumatism are: the lack of teacher control over students' behavior during lessons and breaks and poorly organized educational work. Studies of existing risks at the educational process were carried out in several ways: legislation on the education-al process organizing analysis, sociological (questionary of students, their parents, teachers, teachers of inclusive educa-tion, employees of supervisory bodies), statistical (emergencies analysis that occurred in educational countries for the last two years) and other methods. The study compiled a list of the most common dangers that pose or may pose a threat to educational process participants in modern schools. The most common are: - unknown gas, which is distributed at school events or at school premises, so it is necessary to plan evacuation drills in case of unknown gas spraying in premises, or detection of explosive or unknown objects in premises or on school area, as well as in case of danger; - the dangers encountered in the school's courtyards - enhanced protection and access restriction to the educational institutions territory of persons who do not directly participate in the educational process and to develop and dis-seminate to students, pedagogical staff the rules leaflet on dealing with suspicious objects; - fires in school buildings - fire safety inspections before the school year start show that a significant percentage of schools do not meet the requirements. The main violations found while fire safety school detecting are: missing or faulty fire systems; improperly connected hydrants; faulty fire extinguishers; missing or faulty external water supply; arrangement of fire-hazardous stretch ceilings; no lightning rod; combustible bases under concealed wires, sockets and switches,; evacuation routes are not illuminated; no fire protection, no fire safety instructions; lattices are fixed on the windows; the door does not open in the exit direction. All educational process participants should know the procedure and sequence of actions in case of fire: 1. The fire department must be notified by telephone (101), to switch on the notification system, to inform the facility manager or the assistant. 2. Evacuate students and pupils from the building on the alarm signal. Evacuation should be performed accord-ing to the developed evacuation scenario in different cases (the event happened during the lesson, during a break, while staying with children in the cafeteria, during events in the assembly hall, at night - for institutions with round-the-clock stay of children, etc.). 3. All puipils evacuated from the building are checked according to the available in groups or classes list (log-book) by name. 4. In the daytime, pupils, groups (classes) are accommodated in the building (on the specified address). At night, they are evacuated to the building (note address). Therefore, knowing the simplest security rules will help to reduce the level of danger at an institution. The need is to create a risk management system that will allow: successfully deal with the risks of different origins and their consequences; take into account the specifics of each situation; ensure adequate powers and responsibilities allocation; respond promptly to changing conditions; optimally apply the necessary resources to reduce risk; eliminate the negative effects of adverse situations and events with minimal resources and in the shortest possible time.

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Chen, Yaping, Qiang Li, Wendou Wu, Xiaohui Liu, Jie Cheng, Xiujuan Deng, Xiaobo Cai et al. « Effects of Lightning on Rhizosphere Soil Properties, Bacterial Communities, and Active Components of Camellia sinensis var. assamica ». Frontiers in Microbiology 13 (23 mai 2022). http://dx.doi.org/10.3389/fmicb.2022.911226.

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Lightning rods have been developed to prevent damage caused by lightning to organisms. However, the biological effect of the current transmitted into the soil through lightning rods is unknown. In this study, we analyzed the effects of lightning on soil properties, the microbial community, and the active components of Pu-erh tea (Camellia sinensis var. assamica) near lightning rods. The results showed that the contents of organic matter and available potassium, copper, and calcium in rhizosphere soil near the lightning rod were significantly higher than those in control soil (P < 0.05), while the contents of total potassium, phosphorus, iron, magnesium, and aluminum decreased. Lightning significantly increased the bacterial diversity of Pu-erh rhizosphere soil compared to control soil samples (P < 0.05). Sphingomonas, Nitrospira, and Reyranella were significantly enriched in soil samples near the lightning rod compared to soil samples far from the lightning rod. Clusters of Orthologous Groups (COG) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses indicated that adenosine/AMP kinase, chitodextrinase, flavorubredoxin, nucleotide metabolism, and carbohydrate digestion and absorption were significantly enriched in the rhizosphere soil samples near the lightning rod compared to the control samples (P < 0.05). β diversity analysis indicated the grounding of the lightning rod contributed to the community differentiation of rhizosphere bacteria. Amino acids, polyphenols, and soluble sugar increased in Pu-erh tea near the lightning rod, while the contents of catechin and anthocyanin decreased in Pu-erh tea near the lightning rod compared with the control sample (P < 0.05). Significant correlations were found among microbial indicators, soil properties, and Pu 'er tea components. This study serves as the first report on the effects of lightning rods on soil properties, microecology, and plant metabolism, which promotes the understanding of the biological effects of lightning, and provides a reference for the rational use of lightning resources.

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Fu, Ya-Peng, Cheng Gao et Bo Yang. « The Effect of Direct Lightning Shielding Rod on Lightning Electromagnetic Fields Aboveground ». Frequenz 71, n^o 5-6 (1 janvier 2017). http://dx.doi.org/10.1515/freq-2016-0016.

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AbstractA practical new type direct lightning shielding rod is designed to reduce the electromagnetic radiation produced by lightning stroking to Franklin lightning rod in the paper. The Finite-Difference Time-Domain (FDTD) method is adopted for analyzing. It is the shielding layer that affects the electromagnetic fields and the insulating medium make no difference. All the electromagnetic fields amplitude obtained decrease for the shielding layer existing, regardless of any condition, but the extent is different. That is, the effect on the horizontal electric field is most noticeable, the vertical electric field comes second, minimum the azimuthal magnetic field. All the field components are affected by shielding layer height and the distance between shielding layer and lightning channel, but not significantly by the shielding layer grounding depth. The shielding effect is more obvious with lower ground conductivity, but the ground relative permittivity makes no difference.

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Gu, Jianan, Hao Chen, Yu Shi, Zhenjiang Cao, Zhiguo Du, Bin Li et Shubin Yang. « Eliminating Lightning‐Rod Effect of Lithium Anodes via Sine‐Wave Analogous MXene Layers ». Advanced Energy Materials, 7 août 2022, 2201181. http://dx.doi.org/10.1002/aenm.202201181.

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Wang, Xiaoxuan, Liang Zhao, Rui Zhao, Yixiang Zhou, Shiyu Wang, Xinyue Chi, Yuanyuan Xiong et al. « Enhanced Electrocatalytic Nitrogen Reduction Inspired by a Lightning Rod Effect on Urchin-Like Co3o4 Catalyst ». SSRN Electronic Journal, 2022. http://dx.doi.org/10.2139/ssrn.4110648.

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Han, Ruoyu, Yuchen Cao, Yakun Liu, Xi Chen, Ting Li, Chen Li et Pengfei Li. « Observation and verification of surface electrical explosion driven by radial‐distributed pulsed current in laboratory lightning strike test ». High Voltage, 8 septembre 2023. http://dx.doi.org/10.1049/hve2.12373.

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AbstractThe laboratory lightning test is essential for assessing the effectiveness of lightning strike protection (LSP). Particularly, direct lightning strike damage can be performed with pulsed current injection into the specimen. This paper focuses on the dynamic process of arc plasma and shock wave behaviour in the vicinity of the ‘strike’ point. A rod‐plate discharge load is built for testing aluminium and coated plate under 40‐kA‐level pulsed current. The visualisation of the luminous discharge plasma and its flow field via high‐speed photography (from different angles) is meticulously designed and implemented, synchronised with electro‐physical diagnostics. The results indicate some new mechanisms for lightning strike damage, apart from the impulse heat loading from the thermal arc. The transient current injection through the arc root concentrates on a thin skin layer (skin‐depth effect), with the radial‐attenuated current density, driving asynchronously electrical explosions on the plate surface. The inhomogeneous Joule heating of the plate leads to outwardly propagating phase transition and shock wave along the conductive surface. In addition, the electro‐thermal instability is observed and regarded as the seed of irregular erosion region. Spectroscopic information reveals two different plasma states of main discharge arc channel and adjacent surface electrical explosion. The correspondence of the physical mechanism of electrical explosion and optical radiation is established. Microscopic images for different regions depict erosion characteristics and summarise influencing factors, further confirming the mechanism above. The research clarifies the role of skin‐depth effect in transaction arc erosion for electrode, complements the electrical explosion theory with unevenly distributed current and helps optimise strategies of LSP.

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Liu, Hai, Wei Huang, Yang Yu et Da Chen. « Lightning-Rod Effect on Nanowire Tips Reinforces Electroporation and Electrochemical Oxidation : An Efficient Strategy for Eliminating Intracellular Antibiotic Resistance Genes ». ACS Nano, 30 janvier 2023. http://dx.doi.org/10.1021/acsnano.2c11811.

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Chiu, Chih-Wei, Yan-Feng Chen, Wen-Ru Chang et Chia-Jung Lee. « Triangular gold nanoplates/two-dimensional nano mica platelets with 3D lightning-rod effect as flexible nanohybrid substrate for SERS bacterial detection ». Journal of Materials Chemistry B, 2022. http://dx.doi.org/10.1039/d2tb02049a.

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Triangular gold nanoplates (TAuNPs) were prepared by a one-step rapid growth method and then reduced and stabilized on two-dimensional nano mica nanoplatelets (NMPs). We also prepared TAuNP/NMP nanohybrids with a...

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