scholarly journals The characteristics of lightning risk and zoning in Beijing simulated by a risk assessment model

2013 ◽  
Vol 1 (4) ◽  
pp. 4115-4154 ◽  
Author(s):  
H. Hu ◽  
J. Wang ◽  
J. Pan

Abstract. In this study, the Cloud-to-Ground (CG) lightning flash/stroke density has been derived from the Lightning Location Finder (LLF) data recorded in recent years. Meanwhile, the vulnerability on land surfaces has been assessed by the classification of the building, outdoor area under the building canopy and open-field area, which makes it convenient to deduce the location factor and confirm the protective capability. Then, the number of dangerous lightning event can be estimated by product of the CG stroke density and vulnerability. Although the human beings and all their material properties are identically exposed to lightning, the lightning casualty risk and property loss risk have been assessed respectively due to their vulnerability discrepancy. The analysis of the CG flash density in Beijing revealed that the JuMaHe river-valley in the southwestern region, the ChangPing–ShunYi zone downwind of the Beijing metropolis, and the mountainous PingGu–MiYun zone near the seashore are the most active lightning areas, with densities greater than 1.5 fl km-2 yr-1. Moreover, the mountainous northeastern, northern, and northwestern rural areas are relatively vulnerable to lightning due to the ability of high elevation terrain to attract lightning and the lack of protection measures. In contrast, lightning incidents by indirect lightning are most likely to occur in urban areas with high population density and aggregated properties, and the property damages caused by lightning are more extensive than those in suburban and rural areas. However, casualty incidents caused by direct lightning strokes seldom occur in urban areas. On the other hand, the simulation based on the Lightning Risk Assessment Model (LRAM) demonstrates that the casualty risk is higher in rural, whereas the property loss risk is higher in urban, and this conclusion is also supported by the historical casualty and damage reports.

2014 ◽  
Vol 14 (8) ◽  
pp. 1985-1997 ◽  
Author(s):  
H. Hu ◽  
J. Wang ◽  
J. Pan

Abstract. In this study, the cloud-to-ground (CG) lightning flash/stroke density was derived from the lightning location finder (LLF) data recorded between 2007 and 2011. The vulnerability of land surfaces was then assessed from the classification of the study areas into buildings, outdoor areas under the building canopy and open-field areas, which makes it convenient to deduce the location factor and confirm the protective capability. Subsequently, the potential number of dangerous lightning events at a location could be estimated from the product of the CG stroke density and the location's vulnerability. Although the human beings and all their material properties are identically exposed to lightning, the lightning casualty risk and property loss risk was assessed respectively due to their vulnerability discrepancy. Our analysis of the CG flash density in Beijing revealed that the valley of JuMaHe to the southwest, the ChangPing–ShunYi zone downwind of the Beijing metropolis, and the mountainous PingGu–MiYun zone near the coast are the most active lightning areas, with densities greater than 1.5 flashes km−2 year−1. Moreover, the mountainous northeastern, northern, and northwestern rural areas are relatively more vulnerable to lightning because the high-elevation terrain attracts lightning and there is little protection. In contrast, lightning incidents by induced lightning are most likely to occur in densely populated urban areas, and the property damage caused by lightning here is more extensive than that in suburban and rural areas. However, casualty incidents caused by direct lightning strokes seldom occur in urban areas. On the other hand, the simulation based on the lightning risk assessment model (LRAM) demonstrates that the casualty risk is higher in rural areas, whereas the property loss risk is higher in urban areas, and this conclusion is also supported by the historical casualty and damage reports.


KIEAE Journal ◽  
2020 ◽  
Vol 20 (6) ◽  
pp. 7-12
Author(s):  
Chul Woong Park ◽  
Giyoung Byun ◽  
Ha-Kyeong Lee ◽  
Kee Moon Jang ◽  
Wonjun No ◽  
...  

2019 ◽  
Vol 78 ◽  
pp. 03004
Author(s):  
Miaomiao Tian ◽  
Wenzhao Li ◽  
Meijuan Ruan ◽  
Jing Wei ◽  
Weiwei Ma

Drinking water quality has become a great concern to the whole society, especially in heavily polluted rural areas. This paper analyzes the water quality of 100 water supping the US Environmental Protection Agency's (USEPA) recommended health risk assessment model. The results showed that the microbial indicators exceeded the standard in the whole year, and some of the water supply units which lead, nitrated and dissolved solids exceeding the standard. The model recommended by EPA is applied to establish risk assessment model for health risk assessment of adults in wet and dry seasons, respectively. Results of HRA indicated that carcinogenic risk of chromium was 7.61E-05a-1 and the risk value of arsenic was 9.92E-06a-1 which exceed the maximum acceptable risk level recommended by USEPA 5.0×10-5 closely to the ICPR recommendation 1.0×10-6. Meanwhile we conduct health risk assessment (HRA) on relevant non-carcinogenic indicators: nitrate is 2.95E-09a-1, the risk value of fluoride (F) is 2.49E-09a-1, the risk value of lead is 2.39E-09a-1 and copper (Cu) 9.00E-10a-1 exceeds the maximum acceptable risk level risk value recommended by USEPA 1.0×10-9. The above indicators require priority control and management of pollutants that are prioritized and managed.


2016 ◽  
Vol 31 (5) ◽  
pp. 1697-1714 ◽  
Author(s):  
John A. Hart ◽  
Ariel E. Cohen

Abstract This study introduces a system that objectively assesses severe thunderstorm nowcast probabilities based on hourly mesoscale data across the contiguous United States during the period from 2006 to 2014. Previous studies have evaluated the diagnostic utility of parameters in characterizing severe thunderstorm environments. In contrast, the present study merges cloud-to-ground lightning flash data with both severe thunderstorm report and Storm Prediction Center Mesoscale Analysis system data to create lightning-conditioned prognostic probabilities for numerous parameters, thus incorporating null-severe cases. The resulting dataset and corresponding probabilities are called the Statistical Severe Convective Risk Assessment Model (SSCRAM), which incorporates a sample size of over 3.8 million 40-km grid boxes. A subset of five parameters of SSCRAM is investigated in the present study. This system shows that severe storm probabilities do not vary strongly across the range of values for buoyancy parameters compared to vertical shear parameters. The significant tornado parameter [where “significant” refers to tornadoes producing (Fujita scale) F2/(enhanced Fujita scale) EF2 damage] exhibits considerable skill at identifying downstream tornado events, with higher conditional probabilities of occurrence at larger values, similar to effective storm-relative helicity, both findings being consistent with previous studies. Meanwhile, lifting condensation level heights are associated with conditional probabilities that vary little within an optimal range of values for tornado occurrence, yielding less skill in quantifying tornado potential using this parameter compared to effective storm-relative helicity. The systematic assessment of probabilities using convective environmental information could have applications in present-day operational forecasting duties and the upcoming warn-on-forecast initiatives.


2010 ◽  
Vol 151 (34) ◽  
pp. 1365-1374 ◽  
Author(s):  
Marianna Dávid ◽  
Hajna Losonczy ◽  
Miklós Udvardy ◽  
Zoltán Boda ◽  
György Blaskó ◽  
...  

A kórházban kezelt sebészeti és belgyógyászati betegekben jelentős a vénásthromboembolia-rizikó. Profilaxis nélkül, a műtét típusától függően, a sebészeti beavatkozások kapcsán a betegek 15–60%-ában alakul ki mélyvénás trombózis vagy tüdőembólia, és az utóbbi ma is vezető kórházi halálok. Bár a vénás thromboemboliát leggyakrabban a közelmúltban végzett műtéttel vagy traumával hozzák kapcsolatba, a szimptómás thromboemboliás események 50–70%-a és a fatális tüdőembóliák 70–80%-a nem a sebészeti betegekben alakul ki. Nemzetközi és hazai felmérések alapján a nagy kockázattal rendelkező sebészeti betegek többsége megkapja a szükséges trombózisprofilaxist. Azonban profilaxis nélkül marad a rizikóval rendelkező belgyógyászati betegek jelentős része, a konszenzuson alapuló nemzetközi és hazai irányelvi ajánlások ellenére. A belgyógyászati betegek körében növelni kell a profilaxisban részesülők arányát és el kell érni, hogy trombózisrizikó esetén a betegek megkapják a hatásos megelőzést. A beteg trombóziskockázatának felmérése fontos eszköze a vénás thromboembolia által veszélyeztetett betegek felderítésének, megkönnyíti a döntést a profilaxis elrendeléséről és javítja az irányelvi ajánlások betartását. A trombózisveszély megállapításakor, ha nem ellenjavallt, profilaxist kell alkalmazni. „A thromboemboliák kockázatának csökkentése és kezelése” című, 4. magyar antithromboticus irányelv felhívja a figyelmet a vénástrombózis-rizikó felmérésének szükségességére, és elsőként tartalmazza a kórházban fekvő belgyógyászati és sebészeti betegek kockázati kérdőívét. Ismertetjük a kockázatbecslő kérdőíveket és áttekintjük a kérdőívekben szereplő rizikófaktorokra vonatkozó bizonyítékokon alapuló adatokat.


Author(s):  
C.K. Lakshminarayan ◽  
S. Pabbisetty ◽  
O. Adams ◽  
F. Pires ◽  
M. Thomas ◽  
...  

Abstract This paper deals with the basic concepts of Signature Analysis and the application of statistical models for its implementation. It develops a scheme for computing sample sizes when the failures are random. It also introduces statistical models that comprehend correlations among failures that fail due to the same failure mechanism. The idea of correlation is important because semiconductor chips are processed in batches. Also any risk assessment model should comprehend correlations over time. The statistical models developed will provide the required sample sizes for the Failure Analysis lab to state "We are A% confident that B% of future parts will fail due to the same signature." The paper provides tables and graphs for the evaluation of such a risk assessment. The implementation of Signature Analysis will achieve the dual objective of improved customer satisfaction and reduced cycle time. This paper will also highlight it's applicability as well as the essential elements that need to be in place for it to be effective. Different examples have been illustrated of how the concept is being used by Failure Analysis Operations (FA) and Customer Quality and Reliability Engineering groups.


2013 ◽  
Vol 19 (3) ◽  
pp. 521-527 ◽  
Author(s):  
Song YANG ◽  
Shuqin WU ◽  
Ningqiu LI ◽  
Cunbin SHI ◽  
Guocheng DENG ◽  
...  

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