The World Wide Lightning Location Network and Convective Activity in Tropical Cyclones

2011 ◽  
Vol 139 (1) ◽  
pp. 175-191 ◽  
Author(s):  
Sergio F. Abarca ◽  
Kristen L. Corbosiero ◽  
David Vollaro
Keyword(s):  
Tropical Cyclones ◽  
World Wide ◽  
Inner Core ◽  
The United States ◽  
Vertical Shear ◽  
Lightning Flash ◽  
Convective Activity ◽  
Atlantic Basin ◽  
Peak Current ◽  
The World

Abstract Lightning flash density in tropical cyclones (TCs) is investigated to identify whether lightning flashes provide information on TC intensity and/or intensity change, to provide further insight into TC asymmetric convective structure induced by vertical shear and storm motion, and to assess how well the World Wide Lightning Location Network (WWLLN) is suited for the observation of TCs. The 24 Atlantic basin TCs that came within 400 km of the United States from 2004 to 2007 are studied. The National Lightning Detection Network is used to analyze flash density as a function of peak current and to evaluate the WWLLN. Flash density is shown to be smaller for hurricanes than for tropical depressions and storms, with this reduction being gradually more pronounced as flash peak current increases. The results suggest that flash density in the inner core is a parameter with potential for distinguishing intensifying versus nonintensifying TCs, particularly in the weaker storm stages where flash densities are largest. Vertical wind shear produces a strong downshear left (right) asymmetry in the inner core (outer rainbands), whereas motion asymmetries are less clear. The unprecedented azimuthal resolution used in this study suggests that as shear strengthens, the azimuthal region of convection in the inner core is sharpened from a width of ∼130° to a width of ∼60°. The radial distribution of flash density is shown to exhibit a relatively narrow region of little activity (between 60 and 120 km from the eye), with increased activity in both regions closer to, and more distant from, the center (i.e., the eyewall and outer rainbands, respectively). Finally, it is shown that the WWLLN captures the convective activity in Atlantic basin TCs remarkably well, despite its low detection efficiency.

Chinese Culture and Internet E-Commerce

2011 ◽  
pp. 267-288
Author(s):  
Jeffrey Hsu
Keyword(s):  
Hong Kong ◽  
Web Sites ◽  
Chinese Culture ◽  
World Wide ◽  
Chinese Language ◽  
The United States ◽  
The Internet ◽  
Cultural Aspects ◽  
The World ◽  
Practical Guidelines

The potential for the Internet and e-commerce in China and Chinese-speaking nations (including Hong Kong, Taiwan and Singapore) is huge. Many experts believe that China will have the second largest population of web surfers, after the United States, by the year 2005 (McCarthy, 2000). Currently, the Internet population in China is doubling every six months (CNNIC, 2001). There are many issues relating to China’s cultural aspects and society, which can impact the design and content of web sites that are directed towards Chinese audiences. Some of these issues include basic differences between Chinese and American/Western cultures, family and collective orientations, religion and faith, color, symbolism, ordering and risk/uncertainty. Attention is given to the differences between the cultures of China, Hong Kong, Taiwan, and Singapore, as well as addressing issues brought up by related theories and frameworks. A discussion of important considerations that relate to using Chinese language on the World Wide Web (WWW) is also included. Finally, insights are gained by examining web sites produced in China and Chinese-speaking countries. This chapter will focus on many of these issues and provide practical guidelines and advice for those who want to reach out to Chinese audiences, whether for e-commerce, education, or other needs.

ORGANIZATION OF GEOPHYSICAL PARTIES FOR FOREIGN EXPLORATION

Geophysics ◽  
1945 ◽  
Vol 10 (2) ◽  
pp. 137-159
Author(s):  
C. H. Dresbach
Keyword(s):  
United States ◽  
World Wide ◽  
The United States ◽  
Accurate Information ◽  
The World ◽  
Preliminary Planning

Current and future requirements of petroleum have produced a strong demand for American personnel, equipment and techniques to be employed in the world‐wide search for oil. Different, and sometimes much more difficult conditions are frequently encountered from those customarily met in the exploration for oil in the United States. A brief consideration of some of these factors is the purpose of this paper. It is concluded that while careful preliminary planning and the design of equipment in the light of accurate information on conditions to be encountered are highly vital factors, the demonstrated and trustworthy character of the personnel conducting the operations is the biggest guarantee of success in the undertaking.

Revisiting Business Historians and the Internet

2000 ◽  
Vol 1 (1) ◽  
pp. 179-181
Author(s):  
K. Austin Kerr
Keyword(s):  
Economic History ◽  
Electronic Mail ◽  
World Wide ◽  
The United States ◽  
Business History ◽  
The Internet ◽  
American Business ◽  
Graphical Interface ◽  
The World ◽  
Made In

During the 1996 annual meeting of the Business History Conference, a session on the World Wide Web attracted considerable attention from curious members (see Business and Economic History 25 [Fall 1996]: 46—54). The Internet was then somewhat of an infant, and most of us, just becoming accustomed to the speed and convenience of electronic mail, were barely aware of the opportunities afforded by the then-new graphical interface known as the Web. No more! At least not in the United States, where advertisers bombard us with their Internet addresses and news accounts inform us of vast fortunes made in new Internet ventures that have not yet turned a profit. There is, in short, a “dot.com” revolution occurring in American business. It is also happening, albeit more slowly, in scholarly and educational circles.

scholarly journals A performance assessment of the World Wide Lightning Location Network (WWLLN) via comparison with the Canadian Lightning Detection Network (CLDN)

2010 ◽  
Vol 3 (2) ◽  
pp. 1861-1887 ◽  
Author(s):  
D. Abreu ◽  
D. Chandan ◽  
R. H. Holzworth ◽  
K. Strong
Keyword(s):  
Standard Deviation ◽  
World Wide ◽  
Detection Efficiency ◽  
Low Frequency ◽  
High Peak ◽  
Peak Current ◽  
Lightning Detection ◽  
The World ◽  
The Mean ◽  
The Difference

Abstract. The World Wide Lightning Location Network (WWLLN) uses globally-distributed Very Low Frequency (VLF) receivers in order to observe lightning around the globe. Its objective is to locate as many global strokes as possible, with high temporal and spatial (<10 km) accuracy. Since detection is done in the VLF range, signals from high peak current lightning strokes are able to propagate up to ~104 km before being detected by the WWLLN sensors, allowing for receiving stations to be sparsely spaced. Through a comparison with measurements made by the Canadian Lightning Detection Network (CLDN) between May and August 2008 over a 4° latitude by 4° longitude region centered on Toronto, Canada, this study found that WWLLN detection was most sensitive to high peak current lightning strokes. Events were considered shared between the two networks if they fell within 0.5 ms of each other. Using this criterion, 19 128 WWLLN strokes (analyzed using the Stroke_B algorithm) were shared with CLDN lightning strokes, producing a detection efficiency of 2.8%. The peak current threshold for WWLLN detection is found to be ~20 kA, with the detection efficiency increasing to ~70% at peak currents of ±120 kA. The detection efficiency is seen to have a clear diurnal dependence, with a higher detection efficiency at local midnight than at local noon; this is attributed to the difference in the thickness of the ionospheric D-region between night and day. The mean time difference (WWLLN – CLDN) between shared events was −6.44 μs with a standard deviation of 35 μs, and the mean absolute location accuracy was 7.24 km with a standard deviation of 6.34 km. These results are generally consistent with previous comparison studies of the WWLLN with other regional networks around the world. Additional receiver stations are continuously being added to the network, acting to improve this detection efficiency.

GEOPHYSICAL ACTIVITY IN 1954

Geophysics ◽  
1955 ◽  
Vol 20 (3) ◽  
pp. 654-670 ◽  
Author(s):  
Sigmund Hammer
Keyword(s):  
United States ◽  
Middle East ◽  
World Wide ◽  
Far East ◽  
Geophysical Methods ◽  
The United States ◽  
Global Scale ◽  
The Far East ◽  
Almost Everywhere ◽  
The World

Geophysical activity in explorations for petroleum on a global scale in 1954 was 6.3% lower than the record high of 1953. Notable increases in geophysical effort in Europe, the Middle East, and the Far East were not sufficient to overcome the very substantial decreases in the United States and Canada. The reduction occurred mainly in seismic operations, which decreased globally by 8.4%. Gravity activity was on the increase almost everywhere with the world‐wide rise of 7.1%. Magnetic and miscellaneous other geophysical methods also showed moderate increases in the neighborhood of one percent.

Classifying Web Usage Behavior in the Workplace

2011 ◽  
pp. 211-234
Author(s):  
Murugan Anandarajan
Keyword(s):  
United States ◽  
World Wide Web ◽  
World Wide ◽  
The United States ◽  
The Internet ◽  
Web Usage ◽  
The World ◽  
International Data ◽  
Data Group ◽  
The Web

The ubiquitous nature of the World Wide Web (commonly known as the Web) is dramatically revolutionizing the manner in which organizations and individuals alike acquire and distribute information. Recent reports from the International Data Group indicate that the number of people on the Internet will reach 320 million by the year 2002 (Needle, 1999). Studies also indicate that in the United States alone, Web commerce will account for approximately $325 billion by the year 2002.

scholarly journals Global Trends in Phytohormone Research: Google Trends Analysis Revealed African Countries Have Higher Demand for Phytohormone Information

Plants ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 1248
Author(s):  
Tapan Kumar Mohanta ◽  
Yugal Kishore Mohanta ◽  
Dhananjay Yadav ◽  
Abeer Hashem ◽  
Elsayed Fathi Abd_Allah ◽  
...  
Keyword(s):  
United States ◽  
Salicylic Acid ◽  
Abscisic Acid ◽  
Jasmonic Acid ◽  
United States Of America ◽  
World Wide ◽  
The United States ◽  
Google Trends ◽  
Search Terms ◽  
The World

The lines of research conducted within a country often reflect its focus on current and future economic needs. Analyzing “search” trends on the internet can provide important insight into predicting the direction of a country in regards to agriculture, health, economy, and other areas. ‘Google Trends’ collects data on search terms from different countries, and this information can be used to better understand sentiments in different countries and regions. Agricultural output is responsible for feeding the world and there is a continuous quest to find ways to make agriculture more productive, safe, and reliable. The application of phytohormones has been used in agriculture world-wide for many years to improve crop production and continues to be an active area of research for the application in plants. Therefore, in the current study, we searched ‘Google Trends’ using the phytohormone search terms, abscisic acid, auxins, brassinosteroids, cytokinin, ethylene, gibberellins, jasmonic acid, salicylic acid, and strigolactones. The results indicated that the African country Zambia had the greatest number of queries on auxin research, and Kenya had the most queries in cytokinin and gibberellin research world-wide. For other phytohormones, India had the greatest number of queries for abscisic acid and South Korea had the greatest number of ethylene and jasmonic acid search world-wide. Queries on salicylic acid have been continuously increasing while the least number of queries were related to strigolactones. Only India and United States of America had significant numbers of queries on all nine phytohormones while queries on one or more phytohormones were absent in other countries. India is one of the top five crop-producing countries in the world for apples, millet, orange, potato, pulses, rice, sugarcane, tea, and wheat. Similarly, the United States of America is one of the top five crop-producing countries of the world for apples, grapes, maze, orange, potato, sorghum, sugarcane, and wheat. These might be the most possible factors for the search queries found for all the nine phytohormones in India and the United States of America.

The Institutional Character of the Judge

1972 ◽  
Vol 7 (3) ◽  
pp. 329-348 ◽  
Author(s):  
Bora Laskin
Keyword(s):  
Great Britain ◽  
World Wide ◽  
Civil Servant ◽  
The United States ◽  
Judicial System ◽  
Parliamentary Democracy ◽  
Trial Judge ◽  
The World ◽  
Per Se ◽  
And Function

It would be an unforgivable presumption on my part if I attempted to give my observations in this lecture a world-wide focus. At best, they may be suggestive beyond the compass of the small part of the world in which I have gained, by study and by experience, the insights which support my words. At the least, they will bring to light my particular appreciation of the liberties and the constraints which judges of courts in a parliamentary democracy enjoy and endure in the discharge of their duties.What do I mean by “the institutional character of the judge”? Imagine, if you will, that a man or a woman has been appointed a member of a court. That person has joined an organization which, by constitution or by statute or by both, has been given form, size and function. The position provides security of tenure, an assured salary, and a pension upon due retirement or after a prescribed number of years of service. It demands a stated length of experience in law which has been underpinned by educational qualifications that any aspirant to membership of the Bar must meet. In my country, as in Great Britain and the United States, and as in Israel, the neophyte judge is neither a civil servant, as is the case elsewhere, nor has he joined a specialized branch of the executive government, as is also the case elsewhere. What faces him or her in his or her work, be it as a trial judge sitting alone or as an appellate judge sitting with two or four or more colleagues? To what extent does the judicial system, of which he or she is now part, absorb him or her, and how much freedom does he or she have, to remain or become an individual per se?

scholarly journals Celebrating Ibn Rushd’s Eight-Hundredth Anniversary

1998 ◽  
Vol 15 (2) ◽  
pp. 167-169
Author(s):  
Majid Fakhry
Keyword(s):  
United States ◽  
World Wide ◽  
Decisive Role ◽  
The United States ◽  
Thomas Aquinas ◽  
Ibn Rushd ◽  
The World ◽  
Arabic Philosophy ◽  
Intellectual Revolution ◽  
Immortality Of The Soul

In the context of the world-wide celebrations of the eight-hundrthanniversary of Abu al-Walid Ibn Rushd, known to Western scholars asAverroes (1126-1198), the Tunisian Cultural Foundation (Bayt al-Hikmah) held an International Averroes Symposium, sponsored jointlywith UNESCO, in Carthage, Tunis, on February 16 to February 22,1998. The symposium was hosted by Abd al-Wahab Buhdiba, Directorof Bayt al-Hikmah, and was inaugurated by the President of Tunisia,Zayn al-Abidin Ali, who declared 1998 Ibn Rushd’s year. This symposiumwas attended by a large number of scholars from France, England,Spain, the United States, Iraq, Lebanon, Syria, Morocco, Libya, andTunisia.It was my good fortune to open the symposium with a lecture titled“Averroes, Aquinas and the Rise of Latin Scholasticism in WesternEurope,” in which I tried to highlight the decisive role Ibn Rushd‘sCommentaries on Aristotle played in the rediscovery of Aristotle inWestern Europe, the resurgence of interest in Greek-Arabic philosophy,and the consequent rise of Latin Scholasticism. Through translations bysuch eminent scholars as Michael the Scot and Heman the German duringthe first decades of the thirteenth century, Ibn Rushd’s work triggereda genuine intellectual revolution in leamed circles. Before long, Latinphilosophers and theologians had split into two rival groups, the pro-Averroists, with Siger of Bradbant (d. 1281) at their head, and the anti-Averroists, with St. Thomas Aquinas (d. 1274) at their head. ”he principalissues around which the controversy tumed were the unity of theintellect, the eternity of the world, the immortality of the soul and thedenial of divine providence. The confrontaton between the two rivalgroups became so acute that in 1270, the Bishop of Paris, Etienne ...

scholarly journals Global ground strike point characteristics in negative downward lightning flashes – part 2: Algorithm validation

2021 ◽  
Author(s):  
Dieter R. Poelman ◽  
Wolfgang Schulz ◽  
Stephane Pedeboy ◽  
Leandro Z. S. Campos ◽  
Michihiro Matsui ◽  
...  
Keyword(s):  
Input Parameter ◽  
Lightning Discharge ◽  
Ground Truth ◽  
The United States ◽  
Lightning Strike ◽  
Lightning Flash ◽  
Large Set ◽  
Success Rates ◽  
Peak Current ◽  
Termination Point

Abstract. At present the lightning flash density is a key input parameter to assess the risk of occurrence of a lightning strike in a particular region of interest. Since it is known that flashes tend to have more than one ground termination point on average, the use of ground strike point densities as opposed to flash densities is more appropriate. Lightning location systems (LLSs) do not directly provide ground strike point densities. However, ingesting their observations into an algorithm that groups strokes in respective ground strike points results in the sought after density value. The aim of this study is to assess the ability of three distinct ground strike point algorithms to correctly determine the observed ground-truth strike points. The output of the algorithms is tested against a large set of ground-truth observations taken from different regions around the world, including Austria, Brazil, France, Spain, South Africa and the United States of America. These observations are linked to the observations made by local LLSs in order to retrieve the necessary parameters of each lightning discharge and serves as inputs for the algorithms. It follows that all three of the algorithms perform well, with success rates up to about 90 % to retrieve the correct type of the strokes in the flash, i.e., whether the stroke creates a new termination point or follows a pre-existing channel. The most important factor that influences the algorithms' performance is the accuracy by which the strokes are located by the LLS. Additionally, it is shown that the strokes' peak current plays an important role, whereby strokes with a larger absolute peak current have a higher probability of being correctly classified compared to the weaker strokes.

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