bluuebunny/crossref_metadata_2025_split huggingface dataset:
Perturbation Methods
Authors: Hasegawa Akira , Kodama Yuji 
Published: November 2023

Abstract
As we have seen in Chapters 3 and 4, the soliton is a solution of an integrable system (the NLS equation) which is obtained by the leading order approximation of the original equation (the Maxwell equations in a dielectric medium). The most important property of solitons is that even during the process of mutual interaction, each of their identities, such as the amplitude (or width) and velocity (or frequency), remains constant (but not phase shift). This remarkable property of the soliton leads to the concept of the fundamental mode of the nonlinear system. However, in a real situation of physical applications of solitons, we have to consider effects of higher order terms and external perturbations to study the stability of the soliton under the influence of these effects. Here we present several perturbation methods to deal with this issue. In doing so, we first derive in Section 5.1 an infinite number of conservation laws of the NLS equation, the fact of which is a consequence of the integrability and is that which leads to the remarkable property of the soliton solution. In this section, we also discuss the Hamiltonian structure of the NLS equation, and the stability of one soliton solutions. Then we observe how these conserved quantities deteriorate due to perturbations, and in the case of a small perturbation, we see in Section 5.2 that this observation actually determines the behaviour of a perturbed soliton solution. This approach gives a simple method to study a perturbed problem. However, it should be noted that the method gives only limited information on the soliton parameters, and not the structure of solitons including their phase and position. These are essential in considering a multi-soliton perturbation problem.
Reshaping Of Solitons And Concept Of Guiding Centre (Average) Solitons
Authors: Hasegawa Akira , Kodama Yuji 
Published: November 2023

Abstract
A major unsatisfactory feature of the long-distance propagation of a soliton in fibres is the effect of fibre loss. The authors have proposed several methods to compensate for this effect (Hasegawa and Kodama 1982; Kodama and Hasegawa 1982, 1983; Hasegawa 1983, 1984). Among these, the concept of Raman amplification using the fibre Raman gain itself (Hasegawa 1983, 1984) was found to reshape the soliton successfully in experiments by Mollenauer et al. (1985). The effect of repeated Raman amplification was further studied numerically by Mollenauer et al. (1986) and the first successful long distance all optical transmission was demonstrated by Mollenauer and Smith (1988). However, the original idea of simple optical amplification (Kodama and Hasegawa 1982) became feasible because of the discovery of the erbium doped fibre amplifier (Mears et al. 1987; Desurvire et al. 1987). Reshaping solitons by the erbium-doped fibre amplifier was first tested and successfully demonstrated by Nakazawa et al. (1989). As a possible alternative to the erbium-doped amplifier, the use of lumped parametric amplifier has been also proposed by Yuen (1992) (see also Kutz et al. (1993)).
Soliton Transmission Control
Authors: Hasegawa Akira , Kodama Yuji 
Published: November 2023

Abstract
In the previous chapter, the guiding centresoliton was introduced for a system where the loss is compensated for by inserting lumped amplifiers periodically along the transmission line. However an amplification is always accompanied by a superposition of noise, which, due to the nonlinearity of the system, modulates a soliton as it passes through the amplifier. Since the noise is a spontaneous emission, the interaction is small. However, after several hundreds of amplifiers, the effects become large and induce random shifts in soliton parameters. The most troublesome of these effects is the frequency (and the velocity) shift which translates into a random jitter of the position. This effect known as the Gordon-Haus limit (Gordon and Haus 1986) is believed to provide limitation of the capacity of a long-distance communication system (Gordon and Mollenauer 1991; Tang and Ye 1993).
Modulation Instability
Authors: Hasegawa Akira , Kodama Yuji 
Published: November 2023

Abstract
A continuous wave with a cubic nonlinearity in an anomalous dispersion regime is known to develop instability with respect to small modulations in amplitude or in phase, called modulational instability. The phenomenon of modulational instability was discovered in fluids (Ostrovskii 1963, 1966; Whitham 1965; Benjamin and Feir 1967), in nonlinear optics (Bespalov and Talanov 1966; Karpman 1967), and in plasmas (Taniuti and Washimi 1968; Tam 1969; Hasegawa 1970, 1971). Modulational instability of a light wave in a fibre was suggested by Hasegawa and Brinkman (1980) as a means to generate a far infrared light source. Akhmediev et al. (1986, 1987) studied the modulational instability by constructing exact periodic solutions of the NLS equation. The first experimental verification of the modulational instability of a light wave in a fibre was made by Tai et al. (1986a). The modulational instability can also be induced by a mixture of a small amplitude light waves with the frequency separation (with respect to the carrier cw wave) falling into the sideband frequency range of instability (Hasegawa 1984). This induced modulational instability can be used to generate an ultra short pulse train with a desired repetition rate. The first experimental evidence of an induced modulational instability was also produced by Tai et al. (1986b). Modulational instability can also be produced by cross phase modulation (Berkhoer and Zakharov 1970; Agrawal 1987). This chapter is devoted to presenting theoretical and experimental analyses of modulational instabilities in fibres.
Object Recognition
Authors: Rothwell Charles A 
Published: November 2023

Abstract
The task of recognizing objects using computers has been investigated fairly broadly since the earliest days of research into machine vision. However, very few reliable systems exist; those that actually work do so in very specific environments and adapt poorly to other circumstances. Until systems are built which can recognize large numbers of objects from realistic scenes, any claims of success should be treated with caution by an independent observer. There is also a unilateral failure to test systems properly over a large number of varying images and conditions. This may be because the complete system building process takes so long, but it is certainly true that a more concerted effort is required to produce consistent methods of testing by which we can judge our efforts.
My Own Right Time
Authors: Woodward Philip 
Published: November 2023

Abstract
The pendulum never ceases to be a source of interest to scientists, yet the mechanisms used to maintain it in oscillation are strangely neglected in the general history of science and technology. In the past, escapements have received attention from scientists of the first rank, such as Galileo, Huygens, Airy and Kelvin. Others, like John Harrison, Pierre Le Roy, Lord Grimthorpe and William Shortt, to name but a few, are almost unknown outside the horological fraternity. Here I must echo the aspirations of Professor David Landes of Harvard University upon discovering the wealth of interest to be found in the history and science of time measurement.
Disturbed harmonic motion
Authors: Woodward Philip 
Published: November 2023

Abstract
At the age of twenty-five, George Airy (1827) wrote a paper on escapement theory which has stood the test of time and become a classic work. Two months later he was appointed Lucasian Professor of Mathematics at Cambridge University. In 1835 he became Astronomer Royal and in 1871 President of the Royal Society. Today, Airy’s paper would be regarded by mathematical physicists as quite elementary, but few things in science are elementary when being done for the first time.
Error correction
Authors: Woodward Philip 
Published: November 2023

Abstract
No sooner have the hands of a watch or clock been set to the correct time than they will start to wander away from it, and once they have lost the place, so to speak, there is no magic by which they can find it again other than by accident. This is an important point of principle. An independent timepiece is constantly predicting the time by a process of dead reckoning, and it is not to be wondered at that the longer it goes without checking, the farther from the truth it will be. Much of the interest of error analysis stems from the fact that different sources of error grow in different ways and at different rates.
Noise modulation
Authors: Woodward Philip 
Published: November 2023

Abstract
Speak to an audio engineer of ‘white noise’ and he will imagine a rushing sound not unlike what we imagine we hear when we put a seashell to our ear. By analogy with the colours that go to make up white light, the adjective ‘white’ means that the intensity or power of the noise is spread uniformly across the whole band of frequencies with which we happen to be concerned. In the correct jargon, the mean power density with respect to frequency is constant. On an oscilloscope, white noise from whatever source looks something like the record in Figure 14.1, but this particular trace shows noise over a band vastly lower down the scale than any musical sounds, lower even than the sounds of thunder or earthquakes. It is a plot of the rate fluctuations of Shortt clock No. 13 in 1938, compared daily with the ‘rhythmic time signal’ from the Rugby radio transmitter.*: The frequency components to be found here are not to be measured in hundreds or thousands of hertz but in millionths! One millionth of a hertz is one cycle in eleven or twelve days.
The enigma of flicker noise
Authors: Woodward Philip 
Published: November 2023

Abstract
Flicker noise presents applied scientists with a problem. It is a widely observed phenomenon by no means limited to clocks. Originally discovered in thermionic valves, it has turned up in many fields other than electronics - in physics generally, medicine, hydrography, the stock market, and even in modern music (a form of noise) - but it is strangely difficult to explain. A generic mechanism for it has been proposed (West and Shlesinger 1989, 1990), but through my own shortcomings, I have not yet succeeded in finding that explanation helpful.
Wallman’s conjecture
Authors: Woodward Philip 
Published: November 2023

Abstract
Clockwork may already have reached its apogee when it was eclipsed by electronics, but curiosity compels us to ask whether extra time might have improved the score. It is a question which has fascinated many scientific horologists. A generation back, the distinguished names which would have sprung to mind were those of Vannevar Bush and John Early Jackson in the United States, who were convinced that pendulum accuracy still had some way to go. Their well-known project was reported in Scientific American (Strong 1960), but as is so often the case the final outcome of the experiment is obscure; one can only presume that it proved a disappointment. It has been reported (Cain and Boucheron 1994) that Jackson was never able to adjust the spring in the ingenious compensator for circular error. Enthusiasts approaching the subject from every angle are too numerous to name, yet by present-day standards progress has been slow.
Lightwave Communications
Authors: Joindot Michel 
Published: November 2023

Abstract
The history of modern lightwave communications systems began at the end of the fifties, with lasers, which were the first optical source with high power and directivity able to be used in a communication system. Gas lasers, needing high supply voltages and relatively large sized, were followed in 1961 by semiconductor lasers, which appeared much more promising, because of their small dimensions and the possibility of modulating them with low currents. More than ten years of research were necessary to achieve reliable enough semiconductor lasers working at ambient temperature.
Introduction
Authors: Semmens P W B , Goldfinch A J 
Published: November 2023

Abstract
Although British Railways operated its last mainline steam locomotives in August 1968, there is still immense interest in the large numbers of them which have been privately preserved. Not only do these operate on the various heritage railways throughout the country, but a select few are passed to operate trains on parts of National rail’s national system. In the museum world various working reproductions of historic locomotives have been constructed, and there is even a brand-new Class Al Pacific being assembled in Darlington at the time of writing. (The former are correctly referred to as ‘reproductions’, rather than ‘replicas’, because they differ in numerous details from the originals, although mirroring fairly accurately their appearance. There is no way in which designs of anything getting on for two centuries old would meet today’s safety standards.)
Transmitting the power
Authors: Semmens P W B , Goldfinch A J 
Published: November 2023

Abstract
In the same way as a heavy lorry has a chassis on which are mounted its motor, transmission, wheels, cab and load, a steam locomotive is constructed around its frames, which, in effect, carry its personal identity. When a locomotive was overhauled, particularly in a major railway’s Main Works, the boiler and many other smaller components became dispersed for repair, and could subsequently appear on various other locomotives of the same type, but the frames retained the machine’s original running number. Only in the largest repair establishments was any spare set of frames kept, and then only for numerically-large classes. These could be substituted, say, when a locomotive which had been particularly badly damaged in an accident arrived for overhaul.
Brakes
Authors: Semmens P W B , Goldfinch A J 
Published: November 2023

Abstract
One of the surprising things about the early steam locomotives was that many of them were not provided with any brakes. In that respect, however, they did not differ from the four-legged contemporary alternative form of motive-power, which was not able to provide much in the way of braking effort to supplement what, if any, was fitted to the vehicles they hauled. Well into the twentieth century, too, it was not unknown for horses to bolt, dragging their load at a high speed through the streets, so the idea of a runaway train did not concern the railway pioneers unduly. In the early days of the steam locomotive, when George Stephenson was asked what would happen if Rocket came across a cow on the line, he is reputed to have replied ‘It would be so much the worse for the coo’! However, had there been investigative journalism in those days, he might have had occasion to regret this statement when that locomotive fatally ran down the President of the Board of Trade at the opening of the Liverpool & Manchester Railway in 1830. (Railways in the UK are nevertheless still required to provide fencing through the countryside that is ‘stock-proof’.)
Elementary considerations
Authors: Scaife B K P 
Published: November 2023

Abstract
Our concern is with the behaviour of insulating materials subjected to electric fields. There is no such thing as a truly insulating substance, that is a material which will obstruct, under all circumstances, the transport of electric charge through it. There is, however, a very large group of materials which may be regarded as electrical insulators in view of their exceptionally low conductivities, ranging from 10-18 S/m to 10-6 S/m; metals have conductivities of the order of 108 S/m, and silicon has an intrinsic conductivity, at room temperature, of the order of 10 S/m (Sillars 1973; Tareev 1975; Blythe 1979).
Basic principles of the calculation of the relative permittivity
Authors: Scaife B K P 
Published: November 2023

Abstract
From the preliminary discussion in Chapter 1 it is dear that the calculation of the relative permittivity, E, in terms of molecular parameters requires a study of the manner in which a vast number of particles react to the imposition of an external electric field. There are two aspects to this: the response of an individual particle to an electric field, and the possible modification of this response by particle interactions.We shall consider the parameters such as molecular polarizability and molecular dipole moment to be given and we shall not attempt to discuss their theoretical foundations.
Electromechanical effects
Authors: Scaife B K P 
Published: November 2023

Abstract
In general, dielectric polarization is always accompanied by mechanical effects which, to a first approximation, depend quadratically on the potential gradient.A dielectric body situated in a non-uniform electric field will be subjected to a net mechanical (ponderomotive) force which may be readily measured. In other situations, where there is no net force, the mechanical concomitants of electrical polarization, apart from a possible torque, are usually very small and much less easily observed.
The electromagnetic field in matter
Authors: Scaife B K P 
Published: November 2023

Abstract
Electromagnetic fields are described by Maxwell’s equations, which are mathematical expressions of basic laws associated with the names of Gauss, Ampère, Faraday and Maxwell.The aim of this chapter is the provision of an explanation of the, so-called, macroscopic Maxwell equations, eqn (1.87), in terms of microscopic variables.
The need for courageous action to prevent obesity
Authors: Brownell Marlene B , Schwarz Kelly D 
Published: November 2023

Abstract
Experts have implored the world for years to take note that obesity, poor diet, and physical inactivity are major public health issues. The world now notices. Health authorities throughout the world now devote considerable attention to at least discussing obesity. Attention from the press and the public has grown as well. There were 4767 obesity-related stories in the media for the 12-month period ending September 2003, a ten-fold increase from the same period ending September 2000 (1).
Thus Spoke Galileo
Authors: Frova Andrea , Marenzana Mariapiera , Mcmanus Jim 
Published: November 2023

Abstract
You might know what is said about Galileo, but not many people know what Galileo himself actually said! His elusive and often misquoted discourse has resulted, over the years, in slurs against his name and reputation as a scientist. Let him speak then, so that he can bring to everyone's attention his message of reason, of intellectual honesty, and of free thinking. A message that, more than ever, is of great relevance in the rampant irrationality of the new millennium. The exposition begins with a blunt 'self-portrait'. A 'forgery' of course, based mainly on extracts from Galileo's writings and private letters; something he would never have dared, nor been allowed, to write for the public. The selection of writings offered includes many of the subjects that were closest to Galileo's heart and mind with lively commentary from both the literary, scientific, and historical viewpoints. For those who want to know the mathematics behind Galileo's theories, each chapter closes with a separate self contained summary. Thus Spoke Galileo will allow the reader to appreciate the work and the writing-style of a great scientist and author who had a tremendous influence on the modern world.
Feynman Diagrams and Pair Interactions
Authors: Bruus Henrik , Flensberg Karsten 
Published: November 2023

Abstract
It is in the case of interacting particles and fields that the power of quantum field theory and Feynman diagrams really comes into play. In this chapter, we develop the Feynman diagram technique for a system of fermions with pair interactions. The primary example we will work with is a gas of fermions interacting through Coulomb interactions, but the technique is derived in a more general framework. In general, the Hamiltonian has two parts H = H 0 + W .
1D Electron Gases and Luttinger Liquids
Authors: Bruus Henrik , Flensberg Karsten 
Published: November 2023

Abstract
The 1D interacting electron gas is very different from its higher dimensional counterparts. The main difference being the breakdown of Fermi liquid theory in 1D. In Chapter 15 we saw that the main achievement of the Fermi liquid theory is that it enables us to picture the elementary excitations in terms of quasi particles. As we shall see in this chapter, the quasi particle excitations are in 1D electron systems replaced by the Luttinger–Tomonaga excitations, a sort of density waves, having a completely different nature. The corresponding electron liquid is denoted the Luttinger liquid.
Early works
Authors: Challet Damien , Marsili Matteo , Zhang Yi-Cheng 
Published: November 2023

Abstract
The Minority Game was introduced and first studied in 1997 (Challet and Zhang 1997). Thereafter, the then tiny community of ‘econophysics’ caught on to it and published, in a period of merely 5 years, over one hundred papers directly concerned with it. This can be considered ‘explosive’ activity in economics, where typical publication times are excruciatingly slow. The reason why almost all the papers related to the Minority Game were published in interdisciplinary physics journals is that there exist multiple hurdles for outsiders like physicists publishing in the mainstream economics venues. Definitely physicists generally feel uneasy about several pillars of mainstream economic theory, such as rational expectations, the efficient market hypothesis and the notion of equilibria to name a few. This approach looks too axiomatic and formal to deal with such complex systems as, for example, financial markets.
Quantum mechanics
Authors: Fox Mark 
Published: November 2023

Abstract
The attribution of a wave function to particles with non-zero rest mass like electrons is called first quantization. The reverse procedure, namely the attribution of particle-like properties to wave fields (e.g. the electromagnetic field), is called second quantization. This chapter, in common with most introductory treatments of quantum mechanics, deals only with first quantization. The formalism of second quantization uses the number representation described in Chapter 8.
Working in Clinical Neuropsychology
Authors: Carpenter Katherine , Tyerman Andy 
Published: November 2023

Abstract
Clinical neuropsychology is concerned with people whose thinking, behaviour, or emotions have become disrupted as a result of brain damage. Such neuropsychological changes often have a major effect on the person and their lifestyle, occupation, and family relationships. Clinical neuropsychology has its own specialist knowledge base of neurology, neuroanatomy, and brain–behaviour relations. However, it still involves work with people with their own everyday life events and stresses who experience psychological problems (such as anxiety and depression) similar to those in mental health settings, in addition to their specific neuropsychological changes.
Conclusion: Working in Changing Contexts and Changing Practice
Authors: Hall John , Llewelyn Susan 
Published: November 2023

Abstract
This final chapter draws together a number of themes that emerge from the preceding chapters. It provides, first, an overview of the contextual, social, and policy issues which have an impact on clinical psychology as a profession, and which have been described in many of the chapters. It then considers the conceptual, professional, and ethical responses of clinical psychology to these issues, leading to potential changes in modes of practice. We are attempting to gaze into a crystal ball in this chapter, which is of course likely to be doomed to failure, as nobody can accurately read the future.