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Government, Radio Research, and Upper Atmospheric Sciences in Britain

Aitor Anduaga

in Wireless and Empire: Geopolitics, Radio Industry, and Ionosphere in the British Empire, 1918-1939

At the end of World War I, Britain and the US confronted a new décor of forces and power. The conflict had redesigned the geopolitical map. The truth is that the interwar years witnessed a struggle ... More

At the end of World War I, Britain and the US confronted a new décor of forces and power. The conflict had redesigned the geopolitical map. The truth is that the interwar years witnessed a struggle for supremacy between both countries in specific fields, of which the upper atmospheric sciences are an excellent example. In Britain, this was a period of consolidation in the organization of scientific services, as in the application of radio engineering and ionospheric physics. As a result, Britain held a position of leadership that would be increasingly shared with the Dominions, though ultimately discussed—and in part overcome—by the US. The underlying reasons for her supremacy are various. The cohabitation of styles, practices, and research schools was fruitful. Three traditions of long-independent pedigree—mathematical-physics Cambridge school, laboratory-based experimental physics, and Humboldtian-style terrestrial physics—converged and intersected in the interwar years.Less

The Realist Interpretation of the Atmosphere

Aitor Anduaga

in Wireless and Empire: Geopolitics, Radio Industry, and Ionosphere in the British Empire, 1918-1939

The discovery of a clearly stratified structure of layers in the upper atmosphere has been—and still is—invoked too often as the great paradigm of atmospheric sciences in the 20th century. Behind ... More

The discovery of a clearly stratified structure of layers in the upper atmosphere has been—and still is—invoked too often as the great paradigm of atmospheric sciences in the 20th century. Behind this vision lies an emphasis—or rather an overstatement—on the reality of the concept of layer. Some historians have attributed this to—somewhat ambiguous—cultural factors. This chapter shows how, in the interwar years, most radiophysicists, for reasons principally related to extrinsic influences and to a lesser extent to internal developments of their own science, fervidly embraced a realist interpretation of the ionosphere. In particular, a specific social and commercial environment came to exert a strong influence on upper atmospheric physicists. This realist commitment is attributed to the mutual reinforcement of atmospheric physics and commercial and imperial interests in long-distance communications.Less

Agricultural Drought in Indonesia

Rizaldi Boer and Arjunapermal R. Subbiah

in Monitoring and Predicting Agricultural Drought: A Global Study

Indonesia is the largest archipelago in the world and comprises 5 main islands and about 30 smaller archipelagos. In total, there are 13,667 islands and ... More

Indonesia is the largest archipelago in the world and comprises 5 main islands and about 30 smaller archipelagos. In total, there are 13,667 islands and islets, of which approximately 6,000 are inhabited. The estimated area of the Republic of Indonesia is 5,193,250 km2, which consists of a land territory of slightly more than 2,000,000 km2 and a sea territory of slightly more than 3,150,000 km2. Indonesia’s five main islands are Sumatra (473,606 km2); Java and Madura (132,187 km2), the most fertile and densely populated islands; Kalimantan or two-thirds of the island of Borneo (539,460 km2); Sulawesi (189,216 km2); and Irian Jaya (421,981 km2), the least densely populated island, which forms part of the world’s second largest island of New Guinea. Of about 200 million ha of land territory, about 50 million ha area is devoted to various agricultural activities. There is nearly 20 million ha of arable land, of which about 40% is wetland (rice fields), 40% is dryland, and 15% is shifting cultivation. In the early 1970s, agriculture contributed about 33% to the gross domestic product. Its share decreased to 23% by the early 1980s and to 16.3% in 1996. However, agriculture is the most important sector in the national economy due to its capacity to employ 41% of the labor force (MoE, 1999). Agriculture is vulnerable to drought. Ditjenbun (1995) reported that in 1994 many seedlings and young plants died due to a long dry season: about 22% of tea plants at age of 0–2 years, 4–9% of rubber plants at age of 0–1 year, 4% of cacao plants at age of 0–2 years, 1.5–11% of cashew nut plants at age of 0–2 years, 4% of coffee plants at age of 0–2 years, and 5–30% of coconut plants at age of 0–2 years. The impact of a long dry season on yields of plantation crops becomes known only a few months later. For example, oil palm production is known 6–12 months after a long dry season (Hasan et al., 1998). Rice is the main food crop severely affected by drought. Less

Geophysical networks

Guido Caldarelli

in Scale-Free Networks: Complex Webs in Nature and Technology

This chapter presents the area of river networks analysis, and provides some description of the analytical and experimental results in this field.

Earth Sciences

Glennda Chui

in A Field Guide for Science Writers

In August 1999, I stood in the ruins of a collapsed apartment building near Izmit, Turkey—one of 60,000 buildings destroyed in 40 seconds by the most ... More

In August 1999, I stood in the ruins of a collapsed apartment building near Izmit, Turkey—one of 60,000 buildings destroyed in 40 seconds by the most powerful earthquake to strike a major city in nearly a century. It was a modern building surrounded by trees and greenery. A couch and a table stood intact in a room bright with potted flowers, now open to the air. A woman's coat had been carefully draped over the remains of a wall. As the stench of death rose around us, I wondered if the coat's owner was buried in the rubble beneath my feet. I was sent to Turkey to chase the science—to bring home lessons for readers who live near a strikingly similar fault system in California. But as I surveyed the damage with a team of scientists and engineers, there was no separating the science from the politics. Covered with a fine film of sweat mixed with dust from crumbled buildings and lime that had been scattered to prevent the spread of disease, we saw firsthand how corruption and greed had conspired with the forces of nature to kill more than 17,000 people. Some buildings were constructed right on the North Anatolian Fault. Its mole-like tracks plowed through barracks that had collapsed on 120 military officers, a highway overpass that fell on a bus, a bridge whose failure cut off access and aid to four villages. Researchers found concrete that was crumbly with seashells, chunks of Styrofoam where reinforcing metal bars should have been. Yet some well-reinforced buildings nicked or even pierced by the fault came through just fine, including an apartment building that moved 10 feet and had its front steps sliced off. Another home was cut in two; half collapsed, the other survived with windows intact. “How the hell?” marveled one engineer. “There's no way that building should stand in an earthquake.” That blend of science, politics, and human nature is just part of what makes earth science so compelling. It goes far beyond the academics of geology and plate tectonics to embrace earthquakes, floods, hurricanes, volcanoes, landslides—natural hazards that affect thousands of people and change the course of civilization. Less

Time-Frequency Representations

Robert J Marks II

in Handbook of Fourier Analysis & Its Applications

The Fourier transform is not particularly conducive in the illustration of the evolution of frequency with respect to time. A representation of the temporal evolution ... More

The Fourier transform is not particularly conducive in the illustration of the evolution of frequency with respect to time. A representation of the temporal evolution of the spectral content of a signal is referred to as a time-frequency representation (TFR). The TFR, in essence, attempts to measure the instantaneous spectrum of a dynamic signal at each point in time. Musical scores, in their most fundamental interpretation, are TFR’s. The fundamental frequency of the note is represented by the vertical location of the note on the staff. Time progresses as we read notes from left to right. The musical score shown in Figure 9.1 is an example. Temporal assignment is given by the note types. The 120 next to the quarter note indicates the piece should be played at 120 beats per minute. Thus, the duration of a quarter note is one half second. The frequency of the A above middle C is, by international standards, 440 Hertz. Adjacent notes notes have a ratio of 21/12. The note, A#, for example, has a frequency of 440 × 21/12 = 466.1637615 Hertz. Middle C, nine half tones (a.k.a. semitones or chromatic steps) below A, has a frequency of 440 × 2−9/12 = 261.6255653 Hertz. The interval of an octave doubles the frequency. The frequency of an octave above A is twelve half tones, or, 440 × 212/12 = 880 Hertz. The frequency spacings in the time-frequency representation of musical scores such as Figure 9.1 are thus logarithmic. This is made more clear in the alternate representation of the musical score in Figure 9.2 where time is on the horizontal axis and frequency on the vertical. At every point in time where there is no rest, a frequency is assigned. To make chords, numerous frequencies can be assigned to a point in time. Further discussion of the technical theory of western harmony is in Section 13.1. Less

Signal and Image Synthesis: Alternating Projections Onto Convex Sets

Robert J Marks II

in Handbook of Fourier Analysis & Its Applications

Alternating projections onto convex sets (POCS) [319, 918, 1324, 1333] is a powerful tool for signal and image restoration and synthesis. The desirable properties of a ... More

Alternating projections onto convex sets (POCS) [319, 918, 1324, 1333] is a powerful tool for signal and image restoration and synthesis. The desirable properties of a reconstructed signal may be defined by a convex set of constraint parameters. Iteratively projecting onto these convex constraint sets can result in a signal which contains all desired properties. Convex signal sets are frequently encountered in practice and include the sets of bandlimited signals, duration limited signals, causal signals, signals that are the same (e.g., zero) on some given interval, bounded signals, signals of a given area and complex signals with a specified phase. POCS was initially introduced by Bregman [156] and Gubin et al. [558] and was later popularized by Youla & Webb [1550] and Sezan & Stark [1253]. POCS has been applied to such topics as acoustics [300, 1381], beamforming [426], bioinformatics [484], cellular radio control [1148], communications systems [29, 769, 1433], deconvolution and extrapolation [718, 907, 1216], diffraction [421], geophysics [4], image compression [1091, 1473], image processing [311, 321, 470, 471, 672, 736, 834, 1065, 1069, 1093, 1473, 1535, 1547, 1596], holography [880, 1381], interpolation [358, 559, 1266], neural networks [1254, 1543, 909, 913, 1039], pattern recognition [1444, 1588], optimization [598, 1359, 1435], radiotherapy [298, 814, 1385], remote sensing [1223], robotics [740], sampling theory [399, 1334, 1542], signal recovery [320, 737, 1104, 1428, 1594], speech processing [1450], superresolution [399, 633, 654, 834, 1393, 1521], television [736, 786], time-frequency analysis [1037, 1043], tomography [1103, 713, 1212, 1213, 1275, 916, 1322, 1060, 1040], video processing [560, 786, 1092], and watermarking [19, 1470]. Although signal processing applications ofPOCS use sets of signals,POCSis best visualized viewing the operations on sets of points. In this section, POCS is introduced geometrically in two and three dimensions. Such visualization of POCS is invaluable in application of the theory. Less

Introduction: Emerging Approaches to the Landscapes of the Early and Middle Woodland Southeast

Alice P. Wright and Edward R. Henry

in Early and Middle Woodland Landscapes of the Southeast

The concept of social landscapes provides an integrative and innovative framework for archaeological research in the Early and Middle Woodland Southeast. Landscape archaeology has a diverse ... More

The concept of social landscapes provides an integrative and innovative framework for archaeological research in the Early and Middle Woodland Southeast. Landscape archaeology has a diverse intellectual history and presents certain analytical challenges, but new methodologies and technologies are enabling researchers to tackle questions about interactions among people and their natural and cultural surroundings. As demonstrated by the chapters in this volume (summarized in the introduction), the landscapes of the Early and Middle Woodland periods in the Southeast–long defined by novel and wide-reaching developments in technology, subsistence, interaction, and monumentality–are particularly amenable to such approaches.Less

Reading Technologies

Edward Jones-Imhotep (ed.)

in The Unreliable Nation: Hostile Nature and Technological Failure in the Cold War

This chapter examines the efforts to make the high-latitude ionogram legible, tracing the effects of that new legibility into wider, resonant views of the relationship between the North and ... More

This chapter examines the efforts to make the high-latitude ionogram legible, tracing the effects of that new legibility into wider, resonant views of the relationship between the North and communication failures. It first focuses on the transformations in the way the high-latitude ionogram was read. The same geophysical phenomena that disrupted Northern radio communications made high-latitude ionograms unreadable using standard techniques. Led by one of its founding members, Jack Meek, the Radio Physics Laboratory developed a set of reading regimes that would make these records readable for the first time. The second part of the chapter investigates how the connections built up through these techniques resonated far beyond the laboratory. By linking Northern geophysics and communications disruptions, the Laboratory furnished visual arguments for how defining elements of Canada’s northern-ness threatened reliable communications, feeding back into broader cultural narratives put forward by the Canadian Broadcasting Corporation and the geographer Louis-Edmond Hamelin.Less

The Final Confrontation

James Lawrence Powell

in Four Revolutions in the Earth Sciences: From Heresy to Truth

This chapter looks at the final confrontation between geophysicists and paleomagnetists over the theory of continental drift. The standard historical geology textbook used in the 1950s did not ... More

This chapter looks at the final confrontation between geophysicists and paleomagnetists over the theory of continental drift. The standard historical geology textbook used in the 1950s did not contain the phrase continental drift. As Bailey Willis had urged, continental drift had indeed been banished from the curriculum of geology. One might expect that the geophysicists and oceanographers of the late 1950s and early 1960s would be more amenable to the new findings from paleomagnetism and the possibility of drift than the geologists. After all, the most convincing new data came from the geophysics of the ocean basins. But some geophysicists, such as Walter Munk, Gordon J. F. MacDonald, and Harold Jeffreys, were even more opposed. This chapter also discusses two meetings, one in 1963 and one in 1964, that capture the reversal of opinion over continental drift. The first focused on ancient climates, the second on geophysics and the new findings from the ocean basins.Less

All This Rubbish

James Lawrence Powell

in Four Revolutions in the Earth Sciences: From Heresy to Truth

This chapter takes a look at some of the scientists who continued to reject continental drift. By the 1970s the majority of geologists had come to accept drift, but some never did: Walter Bucher, ... More

This chapter takes a look at some of the scientists who continued to reject continental drift. By the 1970s the majority of geologists had come to accept drift, but some never did: Walter Bucher, Maurice Ewing, and Harold Jeffreys, for example. Those who continue to insist they were right the first time, in spite of accumulating evidence to the contrary, are stuck forever with their original belief. They are entitled to their opinions, but they can also influence their students and followers to stick with them long past the time at which dissent is reasonable. As the person responsible for the collection of most of the data that led to the discovery of plate tectonics, Ewing is the most interesting dissenter. Jeffreys, by all accounts the leading geophysicist of several generations, was willing to let fossils trump geophysics as a source of evidence in support of continental drift.Less

Edmond Halley

Allan Chapman

in Oxford Figures: Eight Centuries of the Mathematical Sciences

In this chapter we describe Edmond Halley’s undergraduate excursion to map the southern stars, and the establishment of his early career. We also discuss his relationship to Flamsteed, Hooke, and ... More

In this chapter we describe Edmond Halley’s undergraduate excursion to map the southern stars, and the establishment of his early career. We also discuss his relationship to Flamsteed, Hooke, and Newton, and describe his astronomical work on comets, nebulae, stellar distribution, the size of the solar system, and geophysics. Several of these advances were carried out while he held the positions of Savilian Professor of Geometry and Astronomer Royal.Less

Neutrons for Peace and Neutrons for War

in The Pontecorvo Affair: A Cold War Defection and Nuclear Physics

This chapter shows Bruno Pontecorvo's pioneering contributions to wartime research in nuclear physics, illustrating how they propelled industrial and military endeavors. Pontecorvo had become one of ... More

This chapter shows Bruno Pontecorvo's pioneering contributions to wartime research in nuclear physics, illustrating how they propelled industrial and military endeavors. Pontecorvo had become one of the most prominent scientists in the Western nuclear research establishment. His presence in the Soviet Union was far more problematic than what a few government officials led the public believe. Pontecorvo's recent work on neutron well logging had caused him to consider the interaction of neutrons and hydrogen-baring or fissionable substances. The development of innovative counters marked a progress in the neutron well logging program. Pontecorvo's expertise in nuclear geophysics helped him in shaping trajectories of nuclear reactor research, which in turn allowed the beginning of a research program on neutrinos that eventually fed into both neutron well logging and pile physics.Less

Emerging Remote Sensing Methods in Underwater Archaeology

Timothy S. de Smet

in New Directions in the Search for the First Floridians

As a critical first step in underwater research, the authors stress the importance of using geophysics for detecting, locating, and determining the extent of archaeological deposits. Magnetometry, ... More

As a critical first step in underwater research, the authors stress the importance of using geophysics for detecting, locating, and determining the extent of archaeological deposits. Magnetometry, multibeam depth sounding, side-scan sonar, sub-bottom profiling, airborne bathymetric LiDAR (ABL), and ground-penetrating radar (GPR) are discussed. The hydrographic GPR case study of stratigraphy and bathymetry took place at the Ryan-Harley site. The ABL case study took place at the Lake George Point Site.Less

Pauline Oliveros: Sonosphere

Douglas Kahn

in Earth Sound Earth Signal: Energies and Earth Magnitude in the Arts

Pauline Oliveros’s notion of the sonosphere is described in terms of physical energies, natural and technological factors, and esoteric and New Age beliefs, with concentration on two compositions: ... More

Pauline Oliveros’s notion of the sonosphere is described in terms of physical energies, natural and technological factors, and esoteric and New Age beliefs, with concentration on two compositions: Primordial/Left, based on the Schumann resonances, and Echoes from the Moon, based on bouncing radio signals off the surface of the moon. Her esoterism is contextualized within similar interests of earlier American composers, Theosophical ideas of earth and larger scale sound, and the mystical music tropes in the theoretical physics of string theory. Her moon bounce composition is discussed in terms of Cold War exigencies, earth-scale television transmissions, the latency in President Nixon’s phone call to the moon during Apollo 11, and Katie Paterson’s more recent moon-bounce artwork.Less

Aiming Guns, Recording Land, and Stitching Map to Territory: The Invention of Cartographic Grid Systems, 1914–1939

William Rankin

in After the Map: Cartography, Navigation, and the Transformation of Territory in the Twentieth Century

Artillery in World War I was guided by the new cartographic technology of “map firing,” which required a rectangular mesh of evenly-spaced lines to be drawn on the maps used in the trenches. These ... More

Artillery in World War I was guided by the new cartographic technology of “map firing,” which required a rectangular mesh of evenly-spaced lines to be drawn on the maps used in the trenches. These systems, known generically as grids, were a powerful alternative to latitude and longitude and came to be useful not just for aiming guns but for a wide variety of civilian tasks as well – everything from recording property titles and laying out highways to stabilizing international boundaries. This chapter traces the long history of grids before World War II – from the work of César-François Cassini de Thury in the eighteenth century through the US State Plane Coordinate System and debates at the International Union of Geodesy and Geophysics in the 1930s – and argues that they presented a serious challenge to the traditional experience (and politics) of using a map. Grid systems were not just lines on paper, but a new kind of full-scale coordinate system that was directly installed as a feature of the landscape. Grids can thus be seen as a mathematical realization of the often-humorous idea of a map at a scale of 1:1, but they were also an important new tool of geographic governance.Less

Vulci 3000: A Digital Challenge for the Interpretation of Etruscan and Roman Cities

Maurizio Forte, Nevio Danelon, David Johnston, Katherine McCusker, Everett Newton, Gianfranco Morelli, and Gianluca Catanzariti

in Digital Cities: Between History and Archaeology

Vulci 3000 is a multidisciplinary archaeological research project that applies cutting-edge technologies to produce a diachronic reconstruction of the Etruscan and Roman site of Vulci (tenth century ... More

Vulci 3000 is a multidisciplinary archaeological research project that applies cutting-edge technologies to produce a diachronic reconstruction of the Etruscan and Roman site of Vulci (tenth century BCE–fifth century CE). Located in the province of Viterbo, Italy, Vulci was one of the largest and most important cities of the Etruscan Dodecapolis—the federation of the most important cities of ancient Etruria, and one of the biggest cities in the first millennium BCE on the Italian peninsula. This project is aimed at the integration of different digital technologies of data capturing, simulation, and visualization for the interpretation and reconstruction of the ancient city.Less