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2.1 Introduction
Physics is known to have made several contributions to the economy of many nations.
Physics has always served as a bridge between knowledge creation and wealth generation,
particularly in high tech industry. The explosive growth of information technology (IT),
microelectronics and telecommunications has its roots in condensed matter physics, materials
physics, semiconductor physics and fiber optics. The knowledge of physics has been
instrumental in the development of enabling technologies for IT hardware, information
processing, information transmission and storage. The semiconductor industry effectively
utilizes the knowledge of solid state physics, chemical physics, plasma physics and materials
physics for several applications. Physicists continue to apply physics knowledge in other
areas also, such as biology and medicine for exploring the properties of DNA, understanding
the way proteins are configured and making improvements in medical imaging.
Evidently, India commands a strong infrastructural base for physics research. Its R &
D institutions are well equipped to lead India in physics research, in developing physics
based technologies directed at economic development of the country and at influencing the
quality of human life. A large number of universities are engaged in postgraduate teaching
and research and doctoral programme. Gauhati University, Guwahati is one of the premier
university in North-East India engaged in physics research and its contributions to the nation
are quite notable. In the perspectives of citation analysis, it is worthwhile to know scope and
structure of those subfields of physics where maximum research had been carried out.
Citation analysis has been used to find out the literature use by the scholars in
different disciplines and the subfields within it. User studies to ascertain information use
19
patterns of scientists are important in planning and designing of information systems and
services. Gupta (1982)9 has rightly declares that “Citations analyses is becoming an important
research tool for the understanding of science, scientists, scientific contributions and
publications. Citation studies and other bibliometric techniques are being applied for the
management of science, analyzing the structure and direction of science, measuring the utility
of journal and relationships between journals and fields and measuring the performance of
scientist. A vast amount of literature is getting published on such kind of evaluative studies.”
The literature in citation analysis has grown tremendous quantity. A survey of the
research trends necessary to identify if any similar study already exists and also with a view
to get knowledge of the process of application of quantitative analysis or methods.
2.2 Scope of Physics and its Branches:
Physics is the basic science. It is the science of matter, motion and energy. It is an
experimental science, creating theories that are tested against observations. Physical
experiments results in measurements, which are compared with the outcome predicted by
theory. A theory that reliably predicts the results of experiments to which it is applicable. It is
said to be embody a law of physics. However, a law is always subject to modification,
replacement or restriction to a more limited domain of a later experiment makes it necessary.
The ultimate aim of physics is to find a unified set of laws governing matter, motion
and energy at small subatomic distances, at the human scale of everyday life, and out to the
largest distances. Broadly, it is the general scientific analysis, with a goal of understanding
how the universe behaves. The domain of physics developed up to about the turn of the 20th
20
century, known as classical physics, can largely account for the motion of macroscopic
objects that move slowly with respect to the speed of light and for such phenomena as heat,
sound, electricity, magnetism and light. The modern developments of relativity and quantum
theory modify those laws in so far as they apply to higher speeds, very massive objects, and
to the tiny elementary constituents of matter, such as electrons, protons and neutrons.
Today, physics is a broad and highly developed subject. Research in the subject is
often divided into four subfields, such as condensed matter physics, atomic, molecular and
optical physics, high energy physics and astronomy and astrophysics. Most physicists also
specialize in either theoretical or experimental research.
An attempt has been made to understand the scope and structure of each subfield of
physics especially, the research areas in Gauhati University in short in the following sections.
2.21 Relativity
The theory of relativity deals with the most fundamental ideas which we use to
describe natural happenings. Those ideas are time, space, mass, motion and gravitation. The
theory of relativity gives new meaning to the old ideas that these words represent.
Historically, the theory developed in two stages. One is the special or restricted relativity
theory. This was published by Albert Einstein in 1905. Another was the general relativity
theory which was put forward by Einstein in 1915.
21
Special Relativity
Special relativity is a theory of structure of space and time, does not treat gravitation.
It was introduced in Einstein’s paper “On the electrodynamics of moving bodies.” Special
relativity is based on two postulates which are contradictory in classical mechanics.
(i) The laws of physics are the same for all observers in uniform motion relative to one
another (Galileo’s principle of relativity).
(ii) The speed of light in a vacuum is the same for all observers, regardless of their relative
motion or of the motion of the source of the light.
The theory has many excellent consequences, some of these are:
i) Time dilation:
Moving clocks are measured to tick more slowly than an observer’s “stationary” clock.
ii) Length Contraction
Objects are measured to be shortened in the directions that are moving with respect to the
observer.
iii) Relativity of simultaneity
Two events that appear simultaneous to an observer. A will not be simultaneous to an
observer B if B is moving with respect to A.
Iv} Mass energy equivalence
Energy and mass are equivalent and transmutable E = mc2
22
General Relativity
General relativity is a theory of gravitation developed by Einstein in the years 1907 -
1915. The development of general relativity began with the equivalence principle, under
which the states of accelerated motion and being at rest in a gravitational field are physically
identical. The upshot of this is that free fall is inertial motion. In other words, an object is free
fall is falling because that is how objects move when there is no force exerted on them,
instead of this being due the force of gravity as is the case in classical mechanics. According
to the theory of general relativity, the planets chooses the shortest possible path throughout
the four dimensional world which is deformed by the presence of the sun. This may be
compared to the fact that a ship or an airplane crossing the ocean follows the section of a
circle rather than a straight line in order to travel the shortest route between two points. In the
same way, a planet or light ray move along the shortest line in its four dimensional world.
According to Einstein’s theory Mercury moves along an ellipse, but at the same time the
ellipse rotates very slowly in the direction of the planet’s motion. The ellipse will turn about
forty three seconds of an arc per century. As per his theory the universe is expanding and the
far parts of it are moving away from us faster than the light. This does not contradict the
theory of special relativity, since it is space itself that is expanding.
2.22 Solid State Physics
Solid state physics is the study of solids, deals with the physical properties of solids or
rigid materials. These properties includes electrical, dielectric, luminescence, ,magnetism,
mechanical strength and clastic and thermal, properties and their understanding in terms of
fundamental physical laws. Solid state physicists mainly try to understand the properties of
23
solids by studying the arrangement and motion of the atoms. The atoms and molecules of
most solids are arranged in a repeated pattern catted crystals. The bulk of solid state physics
theory and research is focused on crystals, largely because the periodicity in atoms in a
crystal and its defining characteristics which facilitates mathematical modeling, and also
because crystalline materials often have electrical, magnetic, optical or mechanical properties
that can be exploited for engineering purposes.
The field of solid state physics has grown up rapidly since about 1946 because of its
importance to industry and its scientific interest. More people are involved in it than in any
other areas of physics. Achievements of solid state physics include the development of
transistors and other devices used in electronic circuits. Solid state physicists have also made
ferrites used in the memory cores of computers, solid lasers, solar batteries, solid luminescent
sources and sensitive detectors for many types of radiation. The computer, communications,
electrical and space industries make use of solid state technology. Quantum theory has given
an understanding of one of the most remarkable properties to be studied in solid state physics,
i.e., superconductivity.
Solid state physics is an expanding field of research with many other challenging
problems today. Some of the problem being studied in solid state physics involves the
interaction of light from intense laser beams with matter. Other areas include the conversion
of electrical energy into light, and improving materials for solid lasers and light sources.
Methods of solid state physics are also being applied to the transfer of energy and electrical
charge in organic systems in biology.
24
According to McGraw Hill Encyclopedia of Science and Technology10
“Most of the
scientists who study the physics of liquids identify with solid state physics and the term “
Condensed matter physics” is increasingly replacing “Solid state physics” a division of
physics “(vol. 16, p. 707).. It includes non-crystalline solids such as glass as well as
crystalline.
2.2.3 X-ray Crystallography
In science, X-rays have a wide variety of use. X-ray crystallography is the science of
determining the arrangement of atoms within a crystal from the manner in which a beam of
X-rays is scattered from the electrons within the crystal. In X-ray crystallography scientists
have been able to discover a great many things about the way atoms are arranged in crystal
and hence in the molecules of chemical substances. This gains knowledge, for example, the
arrangements of the molecules which are responsible for the fact that rubber stretches, or that
oil is a good lubricant. When a beam of X-rays is shot through a substance, a delicate
measuring device shows how much X radiation is absorbed. Such measuring devices are so
sensitive that they can show the difference in the amount of X-rays absorbed between 99 and
100 sheets of paper. This make it possible for the physicists to know how much of certain
materials may be found in the substance. In this way the amount of ethyl gasoline can be
measured readily.
The key step in X-ray crystallography is the diffraction of X-rays from a crystalline
material. A crystal is a solid in which a particular arrangement of atoms is repeated
indefinitely along three principal directions known as the basis vectors. A wide variety of
materials can form crystals, such as salts, metals, minerals semiconductors as well as various
25
inorganic, organic and biological molecules which has made X-ray crystallography
fundamental to many scientific fields. Although it is most informative to diffract X-rays from
a single, large crystal with few defects, such crystals may be difficult to obtain; for simple
materials, it may be possible to reconstruct the atomic structure from the X-ray diffraction of
polycrystalline samples, a technique known as X-ray powder diffraction.
After a crystal has been obtained or grown in the laboratory, it is mounted on a
goniometry and bombarded with X-rays, producing a diffraction pattern of regularly spaced
spots known as reflections. The crystal is gradually rotated and a diffraction pattern is
collected for each distinct orientation of the crystal. These two-dimensional images are
converted into a three- dimensional model of the density of electrons within the crystal using
the mathematical method of Fourier transforms and chemical data on the sample. The
positions of the atomic nuclei are deducted from this electron density and chemical data
producing a model of the atoms within the crystal.
X-ray crystallography is useful in identifying known materials, characterizing
materials and in discerning materials that appear similar by other experiments. X-ray crystals
structures can also account for unusual electronic or elastic properties of a material, shed light
on chemical interactions and processes, or serve as the basis for understanding enzymatic
mechanisms and designing pharmaceuticals against diseases.
2.2.4 Plasma Physics
Plasma in a physics, is a gas that contains roughly equal numbers of positively and
negatively charged particles, usually positive ions and electrons. Plasma is generated by
26
ionizing a gas, either by heating it to a high temperature or passing high energy electrons
through it. It is sometimes referred to as the fourth state of matter, distinct from the solid,
liquid and gaseous states.
When energy (e.g., hear) is continuously appeared to a solid, firstly it melts, then it
vapors and finally electrons are removed from one of the neutral gas atoms and molecules
yield a mixture of positively charged ions and negatively charged electron, while overall
neutral charge density is maintained. When a significant portion of the gas has been ionized,
properties will be altered so substantially it little resemblance to solids, liquids and gases
remain. A plasma is unique in the way in which it interacts with itself, with electric and
magnetic fields, and with its environment. So, plasma can be thought of as a collection of
ions, electrons neutral atoms and molecules, and photons in which some atoms are being
ionized simultaneously with other electrons recombining with ions to form neutral particles,
while photons are continuously being produced and absorbed.
It has been estimated that more than 99% of the universe is in the plasma state. On the
earth, plasmas are much less common. Lightning is a familiar natural manifestation and
fluorescent lights are a practical application. Plasma application and studies make use of an
enormous range of plasma temperatures, densities and neutral –pressures. They extend from
plasma processing applications at relatively low temperatures (such as plasma etching of
semiconductor chips at low pressure or plasma cutting torches at atmosphere pressure) to
studies of controlled fusion at very high temperatures.
All of the observed stars, including the sun, consist of plasma, as do interstellar and
interplanetary media and the outer atmospheres of the planets. Although most terrestrial
27
matter exists in a solid, liquid or gaseous state, plasma is found in lightning bolts and auroras,
plasmas in gaseous discharge lamps (neon lights), and in the crystal structure of metallic
solids. Plasmas are currently being studied as an affordable source of clean electric power
from thermonuclear fusion reactions. In space and fusion plasmas, plasmas are normally
magnetized while in application plasmas on earth, such as plasma processing, both
magnetized and unmagnetised plasmas are employed. Plasmas may be used for electrical
rockets. In this application a very high exhaust velocity could be created by utilizing
electrical power generated on the space ship to accelerate a plasma. While only small vehicle
accelerations can be produced with engines of this type, they can operate for very long
periods of time..
2.2. 5 Electrons Physics
The name of electronics comes from electrons, the tiny negatively charged particles of
atoms. It deals mainly with the flow of electronics through vacuum tubes, gas filled tubes,
transistors and other devices. According to Encyclopedia Britannica11
, “Electronics, branch
of physics that deals with the emission, behaviour and effects of electrons (as in electron
tubes and transistors) with electronic devices.”(vol. 4, p. 438). Although it is considered to be
a theoretical part of physics but the design and construction of electronic circuits to solve
practical problems is an essential technique in the field of electronic engineering and
computer engineering. This science starts about 1908 with the invention by Dr. Lee De Forest
of the valve. Before 1950, this science was named ‘Radio’ or Radio techniques because that
was its principal application.
28
Most of electronics consists of the science of using vacuum tubes, transistors, and
other electronic devices to control small electronic signals. These signals may represent
sounds, such as the radio sounds. They may make up the pictures we see on television. In
computers, the signals may represents numbers, or words used to find information, make
reservations, control machines or processes, or solve problems for businessmen and
scientists. These electronic signals make it possible for electronic devices to aim guided
missiles or to give motion pictures their voice. The electronic microscopes that help scientists
to see tiny germs are electronics.
Electronics deals with flowing electrons. When electrons flow, they form an
electronic current and can be put to work. But, in order to flow, electrons must be free to
move. To understand electronics, we must understand few things, such as (1) the nature of
matter (2) how electrons escape from atoms (3) how electronics makes electrons flow and (4)
how electronics controls an electron flow. Electronics puts these principles for work by
means of (1) vacuum tubes and (2) gas filled tubes. Some of these principles are also
important in solid state physics, such as transistors.
Vacuum Tubes
A vacuum tube is a metal or glass tube from which almost all the air has been
removed so that air atoms and molecules will not interfere with the electron flow. Vacuum
tubes amplify and rectify electric currents in electronic devices, and produce signals by
oscillation. The main types of vacuum tubes include(1) diodes (2) triodes (3) microwave
tubes (4) multielectrode (5) electron beam tubes (6) particle accelerators, and (7)
photoelectric cells.
29
Gas Filled Tubes
Gas filled tubes contain small amount of various types of gases. These tubes can
produce light, charge alternating current to direct current and control machinery. The chief
type of gas filled tubes includes (1) neon signs and fluorescent lights (2) thyratrons, and (3)
mercury pool rectifiers.
The role of electronics is very important in the present society. In the home,
electronics makes possible radio, television and telephones. In industry, electronic devices
operate atomic reactors. They regulate the current used in spot welding and control the speed
of lathes and other machines driven by electronic motors. Teletypewriters, facsimile are
electronic communication devices. In space, electronic devices power satellites, communicate
between earth and space craft and perform other complicated jobs. In national defense, radar
can detect missiles flying thousands of miles away. It also aims guns and missiles at planes,
ships and other targets. In science, astronomers use electronic devices to control telescopes
and to photograph stars and measure their light. Biologists use electron microscopes to study
viruses and other small organisms. Electronic computers solve complex scientific problems.
In the field of medicine, electronic devices, such as X-rays, diathermy machine,
electrocardiographs, electro encephalographs and also electronic hearing aids are used to
detect and ailment of different diseases in our body.
2.26 Nuclear Physics
Nuclear physics is the branch of physics that deals with the nucleus of the atom.
Nuclear physicists seek to understand the structure of the nucleus and how the particles
30
within it act upon one another. The nuclear domain occupies a central position between the
atomic range of forces and sizes and those of elementary particle physics, characteristically
within the nucleons themselves. As the only system in which all the known natural forces can
be studied simultaneously, it provides a natural laboratory for the testing and extending of
many fundamental symmetric and laws of nature. The supreme achievement of nuclear
physicists has been the development of practical atomic energy.
The history of nuclear physics began with the discovery of the nucleus by Rutherford
in 1911. While the work on radioactivity by Becquerel Pierre and Maire Cure predates this,
an explanation of radioactivity would have to wait for the discovery that the nucleus itself
was composed of smaller constituents, the nucleons. Attempts to split the atom led to the
discovery of nuclear fission.
Nuclear scientists study the nucleus by bombarding it with high speed particles. Some
of these nuclear projectiles merely glance off the nucleus or are scattered. This scattering
allows physicists to gain knowledge about nuclear forces, particularly about the size of the
nucleus. Other particles do not bounce off the nucleus, but penetrate into it. These may
produce nuclear disintegrations or transformations. In a few cases, as in the bombardment of
an isotope of the element uranium (U – 235), the atomic fissions (split in two). Fission is a
process where nuclei are split and a great deal of energy is released or absorbed. Fission has
been used for nuclear reactors and atomic bomb. Bombardment of the nucleus with very high
energy particles has resulted in the artificial production of sub-nuclear particles known as
mesons. These are of special interest to nuclear physicists, because they may explain the
nature of the nuclear forces.
31
Fusion, in which nuclei are meshed into larger nuclei, is almost the oppositive of
fission. So far, has only been implemented in the hydrogen bomb. However, since fusion
provides a much greater supply of energy then does fission, Nuclear scientists are working
very hard to create fusion reactors. Two possible designs still being engineered include the
Russian tokamak and laser fusion.
2.2.7 Astrophysics
Astronomy is the branch of astronomy that deals with the physical nature of the
universe, including the physical properties (luminosity, density, temperature) and chemical
composition of celestial objects such as stars, galaxies and the interstellar medium, as well as
their interactions, The Encyclopedia Britannica12
defines it as, “Astrophysics, branch of
astronomy concerned primarily with the properties and structure of cosmic objects, including
the universe as a whole”(vol. 1, p. 657). Astrophysicists use many of the principles and
theories of physics, such as mechanics, electromagnetism, statistical mechanics,
thermodynamics, quantum mechanics, relativity, nuclear and particle physics and atomic and
molecular physics.
Astronomy is very ancient subject and it was long separated from the study of
physics. Aristarchus of Samos(c.310 – c.250 B C.} first put forward the notion that the
motions of the celestial bodies could be explained by assuming that the earth and all the other
planets in the solar system orbited the sun. Unfortunately, in the geocentric world of the time,
Aristarchus heliocentric theory was deemed outlandish and heretical for centuries. Then,
Nicolaus Copernicus revived the heliocentric model in 16th
century. In 1609, Galileo
discovered the four brightest moons of Jupiter and documented their orbits about that planet
32
which again contradicted the geocentric dogma. Later, celestical mechanics, the application
of Newtonian gravity and Newton’s laws explain Kepler’s laws of planetary motion were the
first unification of astronomy and physics. At the end of the 19th
century, the element helium
was first discovered in the spectrum of the sun and only later on earth. During the 20th
century, spectroscopy advanced was necessary to understand the astronomical and
experimental observations.
Majority of astrophysicists are dealt with observational astrophysics and theoretical
astrophysics. The majority of astrophysical observations are made using the electromagnetic
spectrum. Radio astronomy studies with a wavelength greater than few millimeters. Radio
waves are usually emitted by cold objects, including interstellar gas and dust clouds. Pulsars
were first detected at microwave frequencies. The study of these waves requires very large
radio telescopes.
Infrared astronomy studies radiation with a wavelength that is too long to be visible,
but shorter than radio waves. Objects colder than stars, such as planets are normally studied
at infrared frequencies.
Optical astronomy is the oldest kind of astronomy. Spectroscopes are the most
common instruments used in it. In this range of telescope, stars are highly visible and many
chemical spectra can be observed to study the chemical composition of stars, galaxies and
nebulae.
Ultraviolet X-ray and gamma ray astronomy study very energetic processes such as
binary pulsars, black-wholes, magnetars, and many others.
33
The study of sun has a special place in observational astrophysics. Due to the
tremendous distance of all other stars, the sun can be observed in a kind of detail unparalleled
by any other stars.
Theoretical astrophysics use a wide variety of tools which include analytical models
when the conditions at the surface are known, astrophysicists can calculate how the
temperature, pressure, and density increase towards the centre by applying the known
principles and methods of theoretical physics. As a result of these calculations astrophysicists
know that the main source of energy of all stars comes from nuclear reactions converting
hydrogen nuclei to helium nuclei. Another theoretical investigation is to calculate the history
and future development of the stars. Theorists in astrophysicists endeavor to create theoretical
models and figure out the observational consequences of those models. Topics studied by
theoretical astrophysicists include stellar dynamics and evolution, galaxy formation, large
scale structure of matter in universe, origin of cosmic rays, general relativity and physical
cosmology including string cosmology and astroparticle physics.
Recent development in astrophysics include spectrum photographs mode with high
altitudes rockets and studies of radio noises from outer space.
2.2. 8 Geophysics
Geophysics is the science of the earth and its atmosphere. Historically of geophysics
has been motivated by the theoretical and practical issues. The term of geophysics was
probably first used in Germany where it appeared in scientific writings of the mid-19th
century. The word geophysics was first used by Forbel13
as “geophysics “ in 1834. According
34
to the McGraw Hill Encyclopaedia of Science and Technology14
geophysics is as “The study
of the earth and its relations to the rest of the other system using the principles and practices
of physics. Geophysics is considered by some to be a branch of geology by others a branch of
physics. It is distinguished from geology by its use of instruments to make direct and indirect
measurements of the phenomena being studied in contrast to the more direct o9bservatons of
geology, and by its concern with other members of the solar system” (vol. 8, p.73).
Geophysics deals with a wide array of geologic phenomena, including the temperature
distribution of the earth’s interior; the source configuration, and variations of the
geomagnetic field and the large scale features of the terrestrial crust, such as rifts, continental
sutures, and mid oceanic ridges. The research of modern geophysics extends to phenomena of
the outer parts of the earth’s atmosphere, such as the ionospheric dynamo, auroral electro jets,
and magnetopause current system and also to the physical properties of other planets and
their satellites.
Geophysics is divided into various sub-disciplines. These can be grouped as per the
portion of the earth with which is concerned although there is much more overlapping. The
geophysics of the main body of the earth includes such branches as said as earth geophysics,
the study of earth’s interior; seismology, the study of earthquakes; geology, the study of the
earth’s crust and the change it has undergone; and geodesy, the study of the shape and size of
the earth and the measurements of distances between points. Oceanography and hydrology is
concerned with the aqueous parts; metrology with the lower atmosphere; aeronomy with the
upper atmosphere and glaciology; concerns the properties and motion of glaciers. In
geomagnetism and geoelectricity, scientists study the earth’ magnetic field and the electrical
currents that flow around the earth. Gravimetriy is concerned with the pull of gravity.
35
Geophysics is an important and extending science. Mineral prospectors use the
principles of geophysics to locate deposits of oil, uranium and other valuable minerals.
Research conducted with geophysical techniques has proved extremely useful in providing
evidence in support of the theory of plate tectonics. Seismographic data for instance, have
demonstrated that the world’s earthquake belts mark the boundaries of the enormous rigid
plates that constitutes the earth’s outer shell, while the finding of paleomagnetic studies have
made it possible to trace the drift of the continents over geologic time.
2.2. 9 Futurology
Futurology is the scientific study of probable and preferable future. Futurology seeks
a systematic and pattern based understanding of past and present, and to determine the
likelihood of future events and trends. It is a newly emerged interdisciplinary subject
studying yesterday’s and today’s change and aggregating and analyzing both lay and
professional strategies and opinions with respect to tomorrow. It includes analyzing the
sources, patterns and causes of change and stability in the attempt to develop foresight and to
map possible futures. Thus futurology seeks a management attitude of constant preparedness.
A scientific probe into future and generation of long term perspectives do help us to get ready
to overcome future crisis, as well as, to grab the future opportunities.
Futurology is defined as the “study of the future”15
]. The term was coined by German
professor Felechthein16
in the mid 1940s, who proposed it as a new branch of knowledge that
would include a new science of probability. Around the world the new field is variously
referred to as futures studies, strategic foresight, futurology, futuristics, futuresthinking,
futuring, futuribles, and prospectiva. Futures studies are the academic fields most commonly
used terms in the English speaking world.
36
Ability to decode signals coding from the future helps a nation face any eventualities
squarely. Futurism seeks to develop better ways of thinking about the future and it also
promotes scrutiny of alternative ways and means of dealing with a wide variety pf imaginable
future.
Futurology as a subject of scientific study is of recent origin, although precisely
knows, who really taught the first course in futuristics. It was however, in 1943 that professor
Ossip K., Flechthein of U.S.A. wrote an essay recommending that future be taught as a
subject. He advances in science, probability, modeling and statistics will allow us to continue
to improve our understanding of probable futures, while this area presently remains less well
developed than methods for exploring possible and preferable futures. Alvin Toffler of the
U.S.A. gave the first course in future in New York city in 1968 at the New School for Social
Research.
The Department of Science and Technology (DST) is the model of Ministry of
Futurology in India. In 1975, DST set up a National Council on Science and Technology
(NST) Panel on Futurology in order to encourage and stimulate future consciousness or
concern for future among universities and other institutes of higher learning and Future
Research.
Future practitioners use a wide range of methods and models, many of which come
from other academic disciplines, such as psychology, mathematics, sociology, engineering,
physics, astrophysics, etc. Future studies takes as one of its important attributes the ongoing
effort to analyze images of the future. The efforts includes, collecting quantitative and
37
qualitative data about the possibility, probability and desirability of change. The plurality of
the term ‘Futures’ in futurology denotes the rich variety of images of the future (alternative
futures), including the subset of preferable futures, that can be studied.
Forecasting is the most important aspects of futurology. It involves foresight and
foretelling future events. To forecast is to foresee, plan, estimate and calculate in advance.
Futurologists base their predictions primarily on data from demography and technology and
that is why they are able to predict a hundred technical innovations very likely in the last
third of the present century. The main forecasting techniques are (i) historical (ii) deductive
(iii) statistical; and (iv) joint opinion. Futurologists use a diverse range of forecasting
methods which includes delphi methods, trend exploration, monitoring, technology
forecasting, time series analysis, cross impact analysis, simulation and modeling, scenario
method, social network analysis and method of least squares, etc.
2.3 Importance of Citation Analysis
Everyday new knowledge are added in the ever-growing universe of knowledge. And
if they are not recorded properly they will be lost one day. Unless we relate the new
knowledge to the old, no one is going to accept the newness of the work. A scientific paper
does not stand alone but it is embedded in the literature of the subject. The nature of this
embedding is specified by the use of reference lists. The fact that a document is mentioned in
a reference list indicates that in the author’s mind there is a relationship between a part or the
whole of the cited document and a part or the whole of the citing document. Citation analysis
is that area of bibliometrics which deals with the study of these relationships (Osarch,
38
1996)17
. Those references are commonly known as citations and the basic tool for this kind of
study is called citation index, which is an ordered and structured list of cited documents.
In recent years, citation analysis has emerged as a useful technique for devising the
trends in scientific research. Citation analysis uses bibliographic references or footnotes to
identify what material is related to a particular topic and is worth reading. In addition to that
it helps in studying how a scientist interacts with his colleagues. Two assumptions can be
made when scientist cite their work too often. These are: (a) The papers selected for citation
are those which have been important to a research activity (b) Citations are indicative of
influence via the literature, in other words, independent authors working on the same
problems cite the same material.
Why do authors cite? Why do scientists quote precedence? There may be one or more
reasons for an author to cite an authority. Weinstock (1971}18
has identified some of the
major reasons of authors behind using references, as listed below:
1. Paying homage to pioneers;
2. Giving credit for related work;
3. Identifying methodology, equipments, etc.;
4. Providing background reading;
5. Correcting ones own work;
6. Correcting the work of others;
7. Criticising previous work;
8. Substantiating claims;
9. Alerting researchers to forthcoming work;
39
10 Providing leads to poorly disseminated, poorly
indexed, or united work;
11. Authenticating data and classes and fact physical constant, etc.;
12. identifying the original publications in which an idea or concept was
discussed;
13. Disclaiming work or ideas of others;
14. Disputing priority claims of others; and
15. Identifying the original publications or other works describing an
eponymic concepts or terms.
Britain and Line (1972)19
discussed the importance of citation as:
1. Identification of key documents and creation of core lists of journals;
2. Study of the coverage of primary journals and other materials in
secondary services;
3. Clustering of documents according to common references and citations;
4. Study of attributes of literature including growth rate, obsolescence,
citation practices;
5. Study of the structure of the scientific literature according to language,
country of origin, age, subject, form, authorship ar any combination of
these attributes; and
6. Study of the historical and sociological aspects of scholarly
communication in science and technology.
40
The citation techniques use citations in scholarly works to establish links. Many different
links can be established such as links between authors, between fields, between scholarly
works, or even between countries. Citations both from and to a certain document may be
studied. One very common use of citation analysis is to determine the impact of single author
on a given field by counting the number of times the author has been cited by others.
Aggregates of citations are commonly used in evaluation studies as indicators for the impact
of publications, as one of the measures of the ‘quality of research groups or even of
individual researchers. Co-citation maps of scientific maps of scientific specialties’ (Brooks,
1985, p.223)20
and also increasingly citation patterns among journals are used to describe the
development of disciplines and specialties, and to identify emerging areas of scientific
enquiry (Brooks, 1986)21.
Citations are indicators of literature use. According to Baughman (1974)22
citation
study is a systematic enquiry into the structural properties of the literature of the subject. He
explains that the structure of literature is a quality, and therefore it is a distinct characteristic.
It is not a given one; rather it is a ‘ continuing processes within the components that go up to
make a literature, this in turn provides the librarian a practical guide to action when it comes
to the matter of selecting materials for his library. Citations are also used successfully as
reading list and in preparation of bibliographies. This value of citations can well be observed
through Science Citation Index, Social Science Citation Index, and Art and Humanities
Citation Index.
The citation approach has some advantage over the user studies. It helps to determine
the usefulness of the literature of a subject according to its age. For instance, the one general
finding of most citation studies is that scientific writing makes use of more recent and nascent
41
information whereas historical writings make use of comparatively older information. This is
a sort of guidelines to the librarian in the formulation of a separate acquisition policy for each
subject. Secondly, Citation approach is independent of any particular collection. Hence, its
findings are universally applicable to all libraries and information centres.
2.4 Citation Analysis: a Literature Review
The literature in citation studies are extensive in nature, hence a review of the
importance works are only attempted in this work. Quite a large number of studies have been
reported from India as well as from the west in the field of science and technology than in
social sciences and humanities. The first user study of any significance based on a more
systematic citation count, was by Gross and Gross23
in 1927. The study was made of the
references in one year’s issues of volume of the year 1926 of the journal of the American
Chemical Society to aid selection of periodicals in the field of chemistry. It just attempt to
rank the journals in chemistry on the basis of numerical counting. The study remains
important for its historical significance that later became that basis and a methodological
direction to the Bradford’s law of Scattering as per the evidence available, it appears that the
bibliometric studies in India started with the publication of an article by Dutta and
Rajagopalan24
in 1958. However it may be noted here that the term ‘Librametry’ was coined
by Ranganathan25
in 1948 and the term was used more or less in the same sense of
bibliometrics in India for quite some time. But it drew least attention of LIS scientists outside
India. Bibliometric studies in India took a farm root in 1963 when a seminar was organized
by DRTC on Documentation Periodicals and quite a few papers were presented in the
conference including foreign ones.
42
2.4.1 Bradsford’s Law
Bradford’s Law of Scattering describes how the literature on a particular subject is
scattered or distributed in the journals. It is based upon an observation that journal articles in
any specific topic show a particular pattern that a fairly large number of articles are
concentrated in a few journal titles while a large number of journals contribute only one or
two articles each.
There are numerous studies that have applied Bradford’s Law to various collection
management problems which include tests of collection adequacy, journal acquisition, and
retention policies, evaluation of indexing and abstracting services, and cost benefit
considerations of additional coverage. Some of the important reviews of literature are
mentioned here.
Lockett (1989)26
examined critically the growth of research associated with the
Bradford distribution through a detailed discussion on the significant papers published
between 1934 – 1987. The review addresses three major concerns of the literature (a )
appropriate formulation of Bradford’s Law (b) parameters of the Bradford distribution,
and,(c) relationship of the Bradford distribution to other distributions
Wooster (1970)27
made a frequency curve on 6-550 journals which published 5500
articles in aerospace research. He reported that first 10 journals published 35% of the articles;
the second 10 brought the total to 45 %, the third 10 to 50 %. The crossover was at 70
journals and 70 %, with perhaps 400 of the journals running from 5 to 1 articles each.
43
Stevens (1953)28
in his paper reported that in chemistry 2 journals were needed to
cover 25% , 7 to cover 50 % and 24 to cover 75% of the total 247 journals covering 3633
citations
As a possible explanation to the variations of the ranks of the cited journals, Garvey
(1979)29
points out that authors would seek to publish their articles in certain journals and not
in others. Egghe (1990)30
has given “a note on different Bradford multipliers” showing that
the multiplier k that appears in the law of Bradford is neither the production of articles per
author nor the average number in many cases. Pontigo and Lancaster (1986)31
have
investigated on “Qualitative aspects of the Bradford distribution” by using two measures of
quality; rate of citation and expert judgment.
Bookstein (1986)32
in his study “Towards multidisciplinary Bradford Law” discusses
the implications for Bradford’s law of the multidisciplinary character of journals and defines
a simple model that indicates the evolution of journals as a competition among subjects for
space. Basu (1992)33
discussed about “Hierarchical distributions and Bradford’s Law”. While
the distribution obtained reproduces the general shape of a cumulative frequency log-rank
graph of publication data, to ensure good fit to data, parameter has to be introduced that may
be considered to incorporate the effects of possible deviation from randomness and is
suggested as an indirect measure of concentration.
Wagner-Dobber (1996)34
has discussed about “Two components of a casual
explanation of Bradford’s Law”. In his study instead of Bradford’s original rank size
distribution he has taken equivalent but more general Pareto distribution while analyzing
periodicals in 20th
century psychology and mathematical logic and testing the hypothesis that
hierarchies of subjects within periodicals correspond to the reception process, defined as the
structure of interests of their readers. Ravichandra Rao (1998)35
has discussed “An analysis of
44
Bradford multipliers”. to identify a suitable model to explain the law of scattering. He
reported that log normal model fits much better than many other models.
Shukla, Saksena and Riswadkar (2001)36
have made “Application of Bradford’s and
Lotka’s distribution to bio-energy literature: a case study based on ten abstracting services”.
They reported that literature related to bio-energy conforms to Bradford’s law of scattering.
They also revealed that the new model developed in their study fits the data very
satisfactorily-r value ranged from 0.952 to 0.998 (for papers from journal titles) and 0.989 to
0.998 (for papers from conference proceedings). The value of p (multiplication factor) for
bio-energy literature ranged from 2.19 to 4.09 (except for IEA and ISA) for articles from
journal titles and from 2.02 to 4.59 for papers from conference titles.
2.4.2 Bibliographic Form
The significance of any publication lies in its representation of particular information
need. The preference of an intellectual form by the users of a certain discipline for publishing
their contributions helps in deciding the policies regarding the indicators to be used in
evaluating the productivity of the scientists. In scientific research, journals tend to be most
preferred form, followed by books. In areas, which involve policy matters and government
activities, the preferred form is reprints. In short, a variety of forms do exists and there are
overlapping in these forms In this regards, some of the important review works in different
disciplines are given below.
Stevens (1953)37
was the first to undertake a comparative study of the materials cited
in Ph. D. dissertations. A total of 6993 citations received from a sample set of 90 theses, 50
on science and 40 on humanities formed the total data. The analysis revealed heavy use of
journal articles in scientific writing and books in humanities; a large number of citations are
used in humanities than in science. Stevens did not stop with this. He undertook the very
45
laborious task of checking the title against the holdings of the libraries of the respective
universities that awarded the degrees. He found that the dissertation on history cited a large
number of titles which were not in the library. From these findings he made the conclusion
that scholar in humanities have to search and make use of materials available in libraries
other than their own.
Begum and Sami (1986)38
studied the trends in Indian agriculture research with the
help of entries in Indian Science Abstract (1970 – 78, 1980 – 80). Analysis of literature
reveals that journal articles are most highly available form of literature accounting for 96.39
percent, followed by the standard, with 1.39 percent and conference literature with 1.1
percent.
Doraswamy (2006)39
made “Analysis of citations cited in Ph. D. theses in botany”. He
analysed a total of 4050 citations from theses were submitted to the Nagarjuna University,
Guntur, Andhra Pradesh during the year 2000 – 2004. The study revealed that journal articles
are the most preferred source of information for the research scholars in botany accounting
for 71.80 percent, followed by books with 17.65 percent of total citations.
A study on the research publications of an Indian marine fisheries research laboratory
(Kabir, 198)40
shows that over 80% of their contributions are in the serials. The proceedings
of conferences, seminars, workshops, etc. are noticed to the second choice (16.5%) of the
scientists of the institute. Contrary to this most common picture are the contributions of the
Philippines based International Centre for Living Aquatic Resources Management
(ICLARM) (Mclean, 1990)41
The number of contributions of ICLARM in the form of report
and semi-technical literature amount to over 57% contributions in the proceedings of the
conferences and chapters in books are the second choice of the scientists of ICLARM (29%).
The contributions to the serial literature are only 13.5% and thus the last choice. In
46
engineering sciences also the authors have been noticed to be the largely publishing their
findings in the non-serial literature. In some subjects, even the technology conference
proceedings are known to have a better impact than any serial in that field (Tapaswi, 1991)42.
Deshpande (1997)43
made citation study of dissertations in library and information
science submitted to Nagpur University, India during the period 1990 – 94. The study
reported that the majority of citations were from journals (68.74%), followed by books
(16.47%). Similarly, the study of Lokhanda (2007)44
also reveals that journals are the most
preferred source of information used by the researchers in the field of library and information
science with 45.16 percent of the total citations. Books are the second highest group
(42.11%), followed by website, reports, seminars, conferences and newspapers with very low
percentages.
Walcott.s (1981)45
national study of randomly selected geoscience dissertations
revealed that 79.6% of the citations were from serials. With nearly 97% of the serials coming
from English language publications, she suggested that geoscience librarians cut back on
purchasing foreign language publications. Potential serial reductions were the impetus for
Walcott’s (1994)46
citation analysis of graduate students’ biology theses and dissertations for
the years 1989 – 1992. She found that they cited approximately 95% serials and only 5%
books.
A fewer studies have examined chemistry dissertations to ascertain materials most
heavily used. An evaluation of the citation analyses literature in science and engineering
shows that most studies focus on journal or monograph use. Gooden (2001)47
examined 30
dissertations accepted in the Department of Chemistry at the Ohio state University between
1996 – 2000 to determine material use. His study revealed that journal articles were cited
47
more frequently than monographs. 85.8% of the total 3,704 citations were journal articles and
only 8.4% of the citations were monographs.
Barooah and Sharma (1999)48
analysed 4,253 citations collected from 19 doctoral
dissertations submitted to various universities by S & T workers working in the area of
organic chemistry during 1977 to 1997 to determine use pattern of literature. They observed
that out of 4,253, major citations (85.42%) were from journal literature. Only 8.3% citations
of the total citations were from books comes in the next.
Youngen (2001)49
examined electronics preprints in the astronomy and astrophysics
literature. For scientists in those fields he argues “that preprints have become a much more
common form of scientific information exchange”. Youngen concluded that electronic
preprints were cited in the most influential astronomy and astrophysics journals and were an
important resource for primary research information.
Bandyopadhyay (2003)50
has investigated ninety two doctoral dissertations submitted
to the University of Burdwan from 1981 to 1990 by the scholars of five different disciplines,
namely, mathematics, physics, mechanical engineering, political science and philosophy
analyzing a total of 11,228 references. In his study he reported that periodicals are used
maximum 991.96%) and books are used the lowest (4.02%) in nuclear physics.
Dutta and Sen. (2000)51
analysed 743 citations appended to 41 research articles
published in the January to April 2000 issues of Indian Journal of Pure and Applied Physics.
They have reported that journal articles were the most predominant form of literature in
physics, accounting for 83% of the total citations and monographs occupy the second position
accounting for more than 10 percent of the literature.
48
2.4.3 Journal Ranking and Core Journals
Journal ranking assists to journal selection by libraries. Citation analysis helps to
produce lists of core journals according to the number of citations received, are the most
likely best buys. Ranking of journals could also aids in evaluating the importance of journals
indicating their popularity among authors for writing their articles. It gives the evidence of
authors’ preferences of one journal over others showing its usefulness in their fields of
interest. Published literature in journal ranking are quite extensive covering a large number of
ranking studies in scientific disciplines and comparatively lesser number in social science
disciplines and humanities. Some important review works with their broad subject fields
reported by some earlier authors are as follows:
Brown (1956)52
employed the citation technique for the analysis of 5430 citations
from six different physiology journals to determine the most frequently cited physiology
serials. The most significant pre “Science Citation Index” study is that reported by brown
which is described as an “attempt to ascertain what conclusions and interference can be
drawn from study of lists of most frequently cited serials in various fields of science and what
results can be obtained from such a study will make the use of libraries more
effective”(p.160).
It is fully realized that while the count of citations presents factual data the
interpretation and inference drawn from such data are necessarily subjective and it is said that
the paper with maximum citations of current periodicals will be more authentic than with
more than with less, and it is quite obvious in science literature than in social science and
humanities.
Citation analysis technique was employed by Sengupta (1971)53
in preparing the
ranking list of periodicals in different disciplines. Sengupta has observed that equal
49
weightage is not to be given to both old periodicals and newly established periodicals, while
ranking the periodicals in terms of frequency of citations received by them. Newly
established periodicals received lesser number of citations because they have been in
existence for lesser number of years compared to older journals. Hence, correction needs to
be made to give more weight to newly established journals.
To correct, for this fact, he has adopted a formula for weighting the enumerated
citations as follows.
C1 = C 19/n X 10/n1
where C1 is the corrected citation
C is the enumerated citation
n is the number of years which the journal is in existence; and
n1 is the number of years for which the journal had been in existence
during the period of which source journal were counted.
Gunjal and Naidu (1985)54
investigated the use of journals in an agricultural library.
The use of journals has been analysed through citations available in theses during 1969 –
1984. In all 3,875 citations were collected from 147 theses. Out of the total citations, the 55%
were found to be journal citations. This comprised of 2,130 citations taken from 161 journals.
The journals cited less than ten times have been ignored from the frequency count. The most
frequently cited journals were just 27 and this set of journals provided 86% citations. Out of
these 27, 20 journals are being published from India. This 27 core journals can be considered
for acquisition in the concerned library.
50
Mahapatra [(1983)55
analysed 17,802 journal citations in botany from 1950 – 1980
and prepared a ranked list. Lal and Panda (1996)5
created a ranked list of the 100 most
frequently cited core periodicals in plant pathology after examining 20 dissertations from the
Department of Plant Pathology at Rajendra Agricultural University. Edwards (1999)57
determined which journal titles were used by polymer science and polymer engineering
graduate students. Her use of citation analysis along with shelving counts enabled her to
make merited cancellation choices. Twenty journal titles were needed to satisfy 61% of the
journal citations in this study. Accordingly only 12 titles were needed to cover 50% of the
journal citations.
Waugh and Ruppel (2004)58
reviewed the literature in detail with regards to the use of
citation analysis to determine the core journals in various fields, such as psychology,
women’s studies and work force education. They also introduced a weighting formula that
not only takes into account the total number of times each journal title is cited but also the
percentage of dissertations in which it is cited. In other words, a journal title that is cited most
often by the greatest number of dissertations gets ranked higher in the list.
Bandyopadhyay and Nandi (2001)59
reported results of a citation analysis study of
nine doctoral dissertations in political science submitted to the Burdwan University (West
Bengal ) from 1991 – 1995 and concludes that the most favoured ( 56.2 percent ) of literature
is the book, followed by periodicals (20.2 percent}. Out of the total, 29 periodicals are used
to satisfy 80 percent of periodical requirements and seven periodicals satisfy 50 percent of
such requirements. The most highly ranked periodical was ‘Economic and Political Weekly’
covering over 20 percent of periodical requirements.
Gobbur, Kamble and Jange (2003)60
have made citation analysis of 2198 citations
from 10 Ph. D. theses of English subject submitted to Gulbarga University, Gulbarga during
51
1980 – 1995 and prepared a ranked list of journals in the concerned subject. They reported
that out of the total, six periodicals are used to satisfy 50 percent of periodical requirements.
The most highly ranked periodical was ‘Journal of Indian Writing in English’ with 13
citations, covering the percentage 3.95.
Kherde (2003)61
investigated ´Core journals in the field of library and information
science “ where he analyses the citations appended to articles that appeared in popular Indian
library and information science journals during the period 1996 and 2001. His study revealed
that ‘Annals of Library Science and Documentation’ ( Annals of Library and Information
Studies ) secured top position in the rank list receiving 114 citations among Indian journals
while ‘College and Research Libraries’ was the most popular among foreign journals.
Ranking of chemistry periodicals has been studied by Singh (1974}62
from the Indian
scientists’ point of view basing the citations in six issues of Indian Journal of Chemistry vol.
8 (1970}. Mohinder Singh (1978)63
has shown how the ranking of chemistry periodicals has
undergone change during 1967 and 1976. A citation analysis of 22 Ph. D. theses in chemistry
submitted to Mangolore University, India was examined by Mubeen (1996)64
to study the
information use pattern of researchers. The study identified 60 core periodicals, out of a total
418, referred to by researchers. The application of Bradford’s Law of Scattering reveals an
exponential trend and the Bradford multiplier is seen to observe a geometric series pattern
Inhaber (1974)65
made analysis of close to a million citations using the SCI data bank
for all scientific disciplines. Physical Review was at the top of the list, but the order changed
when he adjusted for Impact and Immediacy.
52
Inhaber’s article “stimulated” Garfield (1974)66
to study what are the journals most
cited by physics journals, where in we observed that physicists cite different physics journals
than other people. The lists of top 50 journals most cited by 188 physics journals were given.
Vlachy (1986)67
briefly reviewed physics related quantitative studies in
“Scientometric analysis in physics – where we stand”.
Karanjai and Mujoo-Munshi (1987)68
has made identification of core journals in
science and technology based on INSDOC’s document delivery demand, part 1 of which has
dealt with physics. Document copy requests during 1980-85 were analysed and it was found
that 50 journals could satisfy 76.66% of residual requests in physics. 113 identified journals
could satisfy a majority of residual requests.
Unzun, Menard and Oezel (1993)69
have studied the “citation status of Turkish
physics publications in foreign journals” and found that on the average, papers from Turkey
that appeared in the American and European journals are cited at rates higher than others.
Consequently, the study is based on SCI data that give more coverage to the stated countries.
More recently, Bandyopadhyay (2003)70
in his doctoral thesis entitled “Bibliometric
analysis of doctoral dissertations of the University of Burdwan: a study of information flow
in some selective disciplines”, made analysis of rank journal of physics and shown that 20
journals can fulfill the 80% of total document requirements in Nuclear Physics.
2.4.4 Authorship Studies
The architect of an intellectual and artistic work is recognized as an author. Joint
authors means showing responsibility for the thought content of the work. Multiple
authorship indicates development of a subject and a tendency of inter institutional and inter
53
disciplinary study. Some of the relevant studies on collaborative research in different subjects
are mentioned here.
Price (1963)71
reported first the trend of multiple authorship after studying the data
from Chemical Abstracts for the period 1910 to 1960. The proportion of two authored papers
had reached about 40% of the total output, three authored papers made up about 15% and
four authored papers 5 to 10%. The proportion of three authored papers showed rapid growth
compared to two authored papers and likewise the four authored papers increased faster than
three authors. Price has pointed out that there has been a consistent trend towards increased
collaboration.
Balog (1979-80)72
has studied the multiple authorship and author collaboration in
agricultural publications based on the paper published in New Zealand Journal of
Agricultural Research from 1958 – 1978. The result of the study reveals that the proportion of
single authored papers declined from 65.6 percent to 34.3 percent, two authored papers
increased from 28.1 percent to 41.4 percent and three authored papers from 42 percent to 16.2
percent with an increase in number of authors per paper from 1.43 to 1.99 as a function of
time.
Maheshwarappa and Mathias (1987)73
have investigated the multiple authorship,
authorship patterns and research collaboration in biological sciences as a whole and in
different disciplines of applied sciences in India during 1965 – 83. The data has been
collected from the Indian Science Abstract of 1965, 1970, 1975, 1980 and 1983 as sample
years. The investigation revealed that the proportion of single authored papers declined from
36.07 percent in 1965 to 14.31 percent in 1983 while multiple authorship showed increasing
trend from 63.3 percent to 85.69 percent with an increase in average number of authors per
paper from 1.92 to 2.25. The variation in the degree of collaboration and the average number
54
of authors per paper was found in different disciplines, thus indicating the variation in the
extent of collaboration in biology, botany and zoology.
Khaiser and Rajendra (1990)74
investigated “Research collaboration in zoological
sciences” analyzing 7854 items published during 1975 – 84. The study reported that 67.02%
of the literature was by multiple authors.
Karisiddappa, Maheshwarappa and Shirol (1990}75
studied “Authorship pattern and
collaborative research in psychology” based on Psychological Abstract for the year 1988,
where 39.43% of the literature accounted for single authorship and the degree of
collaboration in psychology was 0.60.
Sen (1997)76
studied article with ten or more authorship. The study showed that 5
percent of the papers published in proceedings of the National Academy of Science, New
York, February – July 1996 were mega authored.
Qin (1995)77
has studied the average number of collaborators per author in
biotechnology. He made “Collaboration and publication productivity: a experiment with a
new variable in Lotka’s Law”. The overall average number of authors per paper was 2.69.
Joshi and Maheshwarappa (1994)78
studied the multiple authorship trends in different
subjects of science and technology. The study revealed that in mathematics 94% of the papers
were single authored in 1940, 79% in 1960 and 44.23% in 1983.
Dutta and Sen (2000)79
have studied “Indian Journal of Pure and Applied Physics – an
analysis of citation pattern”. The study indicates that single authored contributions were
around 25%, two and three authored contributions account for around 58%, and three or more
55
than authors around 16%. The study revealed that around 74% of the contributions were the
result of team work.
Bandyopadhyay (2001)80
studied “Authorship pattern in different disciplines”
analyzing 92 doctoral theses submitted to the Department of Mathematics, Physics,
Mechanical engineering, Philosophy and Political science, University of Burdwan, India from
1981 to 1990. The study showed that multiple authored articles were found maximum in
physics(62.24%0, 36.6% of the articles in mechanical engineering, 36.3% of the articles in
mathematics, 12.3% of the articles in philosophy and only 3.85% of the articles in political
science were multiple authored. It also revealed that multiple authorship trend has increased
steadily through decades (1950 – 1990) in all the branches of physics and mathematics.
2.4.5 Age and Obsolescence Studies
The study of age of literature based on citations has appeared in the literature since
long. The synchronous studies go back to 1927 by Gross and Gross (1927)81
in chemistry and
continued by different authors in various disciplines of sciences, humanities, social sciences
and technology. Burton and Kebler (1960}82
who first introduced the term half-life in the
literature studies in 1960. Premier works like that of Brooke’s (1970)83
reported that if growth
rates of output of literature and number of contributors are equal than the obsolescence rate
remains constant. Kent’s (1987)84
study of obsolescence explains about the measures for
determining the extent to which library materials are used and determine the storage of
discarding points. Egghe and Rousseau (2000)85
explained the notions aging, obsolescence,
impact, utilization and their relations. Jagannath (1999)86
discussed in her paper how reading
materials have become obsolete over the years due to changes in thought content, language,
style of presentation and usage of new terminologies and deterioration in physical body or
56
document carrier. Pichappan and Sangaranachiyar (1996)87
have emphasised that it is
necessary to include eponyms, anonyms and footnotes in age studies.
Similar studies were also conducted by many workers on different subjects. Marton
(1985)88
in his article “Obsolescence or immediacy? Evidence supporting Price’s
hypothesis”. has analysed the time distribution of citations given by five leading journals in
each of seven life science disciplines and reported that the decrease in the frequency of
citations is faster in the early years i.e., 5 – 10 years than later. The results are discussed as
evidence in supporting price’s immediacy factor. Sangam (1989)89
has studied the
“Obsolescence of literature in economics” analysing 1840 references from ten doctoral theses
accepted during 1964 – 1982 by Karnataka University. The half-life of cited journals and
books are reported as 9.47 and 15.7 years respectively.
Verma and Verma (1993)90
have analysed a “Study of age distribution of journal
citation in the American Economic Review” where journal citations were accounted for
58.01%. Median age was found to be six years. They reported that the first two age groups 0
– 4 and 4 – 9 were accounted for 68.4% of the total number of citations.
Musib (1987)91
has made “Age of literature studies in philosophy”. He analysed
34,296 references and footnotes collecting from the articles published in eight journals in the
fiels of philosophy from 1970 – 80. The study revealed that 50% of journal citations were
slightly over 0 – 5 years and those of book citations were slightly over 0 – 9 years.
Biradar and Sampath Kumar (2003)92
in their study examined in the light of
obsolescence of literature, annual aging factor, mean life and utility factor of periodicals in
the field of chemistry. The average half-life of chemical literature was found to be 11.8 years.
The average annual aging factor of literature was found to be 0.9754. Mujoo-Munshi,
57
Karanjai and Sen (1991)93
have made “Citation behaviour of chemical scientists: a case
study”. The study shown that Indian authors generally cite older references where as
American authors quote more recent literature irrespective of their place of work.
Shaw (1986)94
has made “Impact, subfields and aging of recently cited physics
monographs” analysing the distribution by subject and date of publication of approximately
1800 monographs cited in a survey of information sources in physics. The half-life of
literature was found to be 5.8 ≠ 0.5 years.
Gupta (1990)95
has made a synchronous citation study of 15 leading physics journals
to determine the obsolescence of Physical Review articles with age. The study shown that the
density of citation to Physical Review has decreased exponentially with a half-life of 4.9
years.
Pillai and Sudhier {2007}96
have made “Citations in the physics doctoral
dissertations: an obsolescence study”. The study reported that the half-life of journals was
found to be 10 years and 15 years for books. The mean year of journal citations were
calculated as 14.19 years and for books 17.79 years.