bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Royal Aeronautical Society 1866 — 1966
Authors: Laurence Pritchard J. 
Published: July 2016

Humanity with all its fearsWith all the hopes of future years,Is hanging breathless on thy Fate.Longfellow.12th January 1966, is the one hundredth birthday of the Aeronautical Society of Great Britain.The story of the first hundred years of the Aeronautical Society began with long data-less periods of unfulfilled hopes. Like the paradoxical supersonic aeroplanes which arrive at their destinations before they are timed to take off, the story of the Society was started fifty years before it began, by Sir George Cayley, who wrote a famous paper on Aerial Navigation, laying down the fundamental principles of heavier-than-air flight.
Some Airship Personalities
Authors: Cave-Browne-Cave T. R. 
Published: July 2016

When Airship No. 1, which had been built at Barrow, was finally abandoned in 1912, her officers were sent to Farnborough as “The Naval Wing” to gain experience of the military airships and of the Royal Aircraft Factory where they were built. A German Parsival Airship, No. 4, and a French Astra Airship, No. 3, were bought by the Admiralty for the Naval Wing.In 1913 I succeeded in getting transferred to the Naval Wing and I found in the Naval Mess a most inspiring community. Lieut. Commander N. F. Usborne was the dominant spirit.
My Early Days at the Royal Aircraft Factory 1914 Onwards
Authors: Stevens H. L. 
Published: July 2016

Some time in the May term in 1914, in my third year, my Supervisor of Studies told me that Mervyn O'Gorman, Head of the Royal Aircraft Factory, as it then was, would be visiting Cambridge and staying with Charles Darwin and might be looking for staff. He offered to arrange a meeting for me if I was interested. I had intended to be a civil engineer, but we agreed that aviation was a coming profession and it would be a good idea to get in more or less on the ground floor.I went to see O'Gorman, and it was eventually agreed that if I got a good place in the tripos I would be taken on at the Factory at a salary of £1 per week and would report on the 1st August.
1908 Onwards—
Authors: Gordon England E. C. 
Published: July 2016

In 1965 we see a world around us seemingly inharmonious and suffering from uncertainty in the regions of religions, politics, economics and culture. How different away back in 1908! Most people in those far off days had convictions and held them to be first principles.They really did believe in the verity of the words of the hymn from which this phrase is quoted—“God made them high and lowly and ordered their estate.” People in 1908 saw nothing peculiar in holding such beliefs. This was the atmosphere in which the activities of the Society were being conducted and was largely the matrix of the thinking of its illustrious and inspired membership.
British Rotorcraft
Authors: Hafner Raoul 
Published: July 2016

This brief historical note on British rotorcraft may be likened to the small visible part of a large iceberg and the reasons for it are these.When I was asked to write this note for the Society's Journal I agreed to undertake the task with certain reservations. In the first instance there was very little time in which to do it. While it was relatively easy to collect the early history from well-established records this did not apply to the more recent developments and here the material needed to be collected from primary sources and to be collated.
Civil Airworthiness
Authors: Tye Walter 
Published: July 2016

This account of the development of civil airworthiness comes from one who has been closely concerned. It is therefore a somewhat personal view. However, a tree in the heart of a wood must be forgiven if it knows best the trees in its immediate vicinity and if its perspective of the whole wood is restricted.I have tended to relate the history of airworthiness to the development of airworthiness regulations, chiefly because these events are more clearly marked historically.
A minimax optimal stop rule in reliability checking
Authors: Gouweleeuw José M. 
Published: July 2016

Consider a machine, which may or may not have a defect, and the probability q that this machine is defective is unknown. In order to determine whether the machine is defective, it is tested. On each test, the defect is found with probability p, if it has not been found yet. Performing n tests costs c

n
dollars and there is a fine of 1 dollar if there is a defect and it is not found on the tests. When should we stop testing, in order to minimize the cost?
This problem is treated in a minimax setting: we try to find a strategy that works well, even for ‘bad’ q's. It turns out that the minimax optimal stop rule can be unexpectedly complicated. For example, if p = 1/2 and c

n
= c
n = 0.25n, then the optimal rule is to start by performing one test. If a defect is found we stop, otherwise we perform a second test. If a defect is found, then again we stop, else toss a coin and stop if this shows heads. If we still have not stopped, a third and last test is performed.
On waiting times to populate an environment and a question of statistical inference
Authors: Bruss F. Thomas , Slavtchova-Bojkova M. 
Published: July 2016

The mathematical model we consider here is the classical Bienaymé–Galton–Watson branching process modified with immigration in the state zero.
We study properties of the waiting time to explosion of the supercritical modified process, i.e. that time until all beginning cycles which die out have disappeared. We then derive the expected total progeny of a cycle and show how higher moments can be computed. With a view to applications the main goal is to show that any statistical inference from observed cycle lengths or estimates of total progeny on the fertility rate of the process must be treated with care. As an example we discuss population experiments with trout.
Conditioned limit theorems for waiting-time processes of the M/G/1 queue
Authors: Hooghiemstra G. 
Published: July 2016

This paper is on conditioned weak limit theorems for imbedded waiting-time processes of an M/G/1 queue. More specifically we study functional limit theorems for the actual waiting-time process conditioned by the event that the number of customers in a busy period exceeds n or equals n. Attention is also paid to the actual waiting-time process with random time index.
Combined with the existing literature on the subject this paper gives a complete account of the conditioned limit theorems for the actual waiting-time process of an M/G/1 queue for arbitrary traffic intensity and for a rather general class of service-time distributions.
The limit processes that occur are Brownian excursion and meander, while in the case of random time index also the following limit occurs: Brownian excursion divided by an independent and uniform (0, 1) distributed random variable.
A renewal density theorem in the multi-dimensional case
Authors: Mode Charles J. 
Published: July 2016

Summary
In this note a renewal density theorem in the multi-dimensional case is formulated and proved. Let f(
x
) be the density function of a p-dimensional random variable with positive mean vector μ and positive-definite covariance matrix Σ, let hn
(
x
) be the n-fold convolution of f(
x
) with itself, and set

Then for arbitrary choice of integers k
1, …, kp–

1 distinct or not in the set (1, 2, …, p), it is shown that under certain conditions

as all elements in the vector
x
= (x
1, …, xp
) become large. In the above expression μ‵ is interpreted as a row vector and μ a column vector. An application to the theory of a class of age-dependent branching processes is also presented.
Equilibrium distributions for systems of chemical reactions with applications to the theory of molecular adsorption
Authors: Orriss J. 
Published: July 2016

Summary
In this paper a stochastic model is set up for a certain type of reversible chemical reaction and a solution given for the equilibrium distribution; this solution is then extended to deal with any system of chemical reactions.
Three different types of reaction are considered:
(1) Several substances Ai
react together and give a set of substances Bj. The reaction is reversible, with the substances Ai
appearing only on one side of the reaction equation and the substances Bj
only on the other.
(2) Several different reactions involving the substances Ai
and Bj
take place simultaneously, but in each reaction equation the substances Ai
can appear only on one side and the Bj
only on the other.
(3) The restriction of the sets Ai
and Bj
to different sides of the reaction equations is removed: any reaction involving any of the substances Ai
and Bj
on either side of the equation is permissible.
The paper concludes with some applications of the results to problems of molecular adsorption.
Looking forwards and backwards in a bisexual moran model
Authors: Kämmerle K. 
Published: July 2016

In this paper a bisexual Moran model is introduced. The population consists of N pairs of individuals. At times t = 1, 2, ·· ·two individuals are born, who ‘choose their parents randomly' and independently of each other. Then one of the pairs is removed and replaced by the two individuals born at that instant.
The extinction probability of the descendants of a single pair and the number of ancestors of a whole generation are studied. A limit result for large population sizes has been derived by diffusion approximation methods.
Epidemics with carriers: The large population approximation
Authors: Pettigrew Hugh M. , Weiss George H. 
Published: July 2016

This paper applies the constant population approximation to the study of epidemics which involve more than a single type of infective. An example of this would be a situation in which both clinically infected individuals and subclinically infected individuals or carriers are present.
We derive equations for the expected numbers of clinically infected individuals and carriers at any time t for the model with zero latent period and infectious periods having negative exponential distributions. From these equations we derive conditions under which a unimodal incidence curve can result, and expressions for the expected total epidemic size.
Markov population processes
Authors: Kingman J.F.C. 
Published: July 2016

Summary
The processes of the title have frequently been used to represent situations involving numbers of individuals in different categories or colonies. In such processes the state at any time is represented by the vector n = (n
1, n
2, …, nk
), where nt
is the number of individuals in the ith colony, and the random evolution of n is supposed to be that of a continuous-time Markov chain. The jumps of the chain may be of three types, corresponding to the arrival of a new individual, the departure of an existing one, or the transfer of an individual from one colony to another.
A uniqueness problem for the envelope of an oscillatory process
Authors: Hasofer A. M. 
Published: July 2016

In a previous paper, the author has described a method for obtaining envelope processes for oscillatory stochastic processes. These are processes which can be represented as the output of a time-varying linear filter whose input is a stationary process.
It is shown in this paper that the proposed definition of the envelope process may not be unique, but may depend on the particular representation of the oscillatory process chosen.
It is then shown that for a class of oscillatory processes which is of particular interest, the class of transient processes, there is a class of natural representations which all lead to a unique envelope process.
Comparison of two treatments when there may be an initial effect
Authors: Scott Elizabeth L. 
Published: July 2016

Consider situations where the treatment may cause an initial effect and may also cause a long-range effect. We want to evaluate the treatment, or to compare two treatments, when the effect of treatment may result from the two distinct mechanisms,M1andM2. We may wish to evaluateM1andM2separately, but we may also want to evaluate their combined effectM3. Examples are given and the general results are applied to the special case arising in weather modification studies and elsewhere: the possible effects are multiplicative and the distribution of non-zero variables is gamma with at most the scale parameter affected by treatment. An example demonstrates that the two components may be too weak to be judged significant while their sum is large and significant. The locally optimumC(α) test is used.There is a brief discussion of the power function of the tests. The asymptotic power agrees well, in general, by the results of the Monte Carlo simulation for the testZ3of the combined effect. If the zero values are discarded and thenZ2employed, there is large bias in the power. The bias is more pronounced if the Wilcoxon, Mann–Whitney test is employed. Notice that the two effects under study may be acting in the same direction or they may be in opposition.
A comparison theorem for conditioned Markov processes
Authors: Roberts G. O. 
Published: July 2016

Intuitively, the effect of conditioning a one-dimensional process to remain below a certain (possibly time-dependent) boundary is to ‘push' the process downwards. This paper investigates the effect of such conditioning, and finds the class of processes for which our intuition is accurate. It is found that ordinary stochastic inequalities are in general unsuitable for making statements about such conditioned processes, and that a stronger type of inequality is more appropriate.
The investigation is motivated by applications in estimation of boundary hitting time distributions.
Some new results on queueing networks with batch movement
Authors: Henderson W. , Taylor P. G. 
Published: July 2016

Product-form equilibrium distributions in networks of queues in which customers move singly have been known since 1957, when Jackson derived some surprising independence results. A product-form equilibrium distribution has also recently been shown to be valid for certain queueing networks with batch arrivals, batch services and even correlated routing.
This paper derives the joint equilibrium distribution of states immediately before and after a batch of customers is released into the network. The results are valid for either discrete- or continuous-time queueing networks: previously obtained results can be seen as marginal distributions within a more general framework. A generalisation of the classical ‘arrival theorem' for continuous-time networks is given, which compares the equilibrium distribution as seen by arrivals to the time-averaged equilibrium distribution.
Homogeneous row-continuous bivariate markov chains with boundaries
Authors: Keilson J. , Zachmann M. 
Published: July 2016

The matrix-geometric results of M. Neuts are extended to ergodic row-continuous bivariate Markov processes [J(t), N(t)] on state space B = {(j, n)} for which: (a) there is a boundary level N for N(t) associated with finite buffer capacity; (b) transition rates to adjacent rows and columns are independent of row level n in the interior of B. Such processes are of interest in the modelling of queue-length for voice-data transmission in communication systems.
One finds that the ergodic distribution consists of two decaying components of matrix-geometric form, the second induced by the finite buffer capacity. The results are obtained via Green's function methods and compensation. Passage-time distributions for the two boundary problems are also made available algorithmically.
Stochastic scrabble: large deviations for sequences with scores
Authors: Arratia Richard , Morris Pricilla , Waterman Michael S. 
Published: July 2016

A derivation of a law of large numbers for the highest-scoring matching subsequence is given. Let Xk, Yk
be i.i.d. q=(q(i))
i∊S
letters from a finite alphabet S and v=(v(i))
i∊S
be a sequence of non-negative real numbers assigned to the letters of S. Using a scoring system similar to that of the game Scrabble, the score of a word w=i
1 · ·· im
is defined to be V(w)=v(i
1) + · ·· + v(im
). Let Vn
denote the value of the highest-scoring matching contiguous subsequence between X
1
X
2 · ·· Xn
and Y
1
Y
2
· ·· Yn. In this paper, we show that Vn/K log(n) → 1 a.s. where K ≡ K(q
,
v). The method employed here involves ‘stuttering’ the letters to construct a Markov chain and applying previous results for the length of the longest matching subsequence. An explicit form for β ∊Pr(S), where β (i) denotes the proportion of letter i found in the highest-scoring word, is given. A similar treatment for Markov chains is also included.
Implicit in these results is a large-deviation result for the additive functional, H ≡ Σ
n &lt; τ
v(Xn
), for a Markov chain stopped at the hitting time τ of some state. We give this large deviation result explicitly, for Markov chains in discrete time and in continuous time.
Nested Monte Carlo study of random packing on the sphere
Authors: Rodgers R. P. C. , Baddeley A. J. 
Published: July 2016

We consider two random sequential packing processes in which spheres of unit radius are randomly attached to the surface of a fixed unit sphere. Independent random spheres are generated and added successively, provided there is no overlap with previous spheres. In model 1, the process stops when a trial sphere intersects one of the previously-accepted spheres. In model 2, random sequential packing, any such overlapping trial sphere is discarded and the next random sphere is tried, until it is impossible to add any further spheres.
Previous workers have conjectured convincingly that no exact analytical solution is possible for this type of problem. We use Monte Carlo simulation methods to estimate transition probabilities for the two models. Because some probabilities are extremely small, a simulation using independent repetitions of the model would be inefficient. We designed a branching process of conditionally binomial trials, and performed over 108 trials on a supercomputer.
Forward and backward processes in bisexual models with fixed population sizes
Authors: Möhle M. 
Published: July 2016

This paper introduces exchangeable bisexual models with fixed population sizes and non-overlapping generations. In each generation there are N pairs of individuals consisting of a female and a male. The N pairs of a generation produce N daughters and N sons altogether, and these 2N children form the N pairs of the next generation at random.
First the extinction of the lines of descendants of a fixed number of pairs is studied, when the population size becomes large. Under suitable conditions this structure can be approximately treated in the framework of a Galton-Watson process. In particular it is shown for the Wright-Fisher model that the discrepancy between the extinction probabilities in the model and in the approximating Galton-Watson process is of order N.
Next, the process of the number of ancestor-pairs of all pairs of a generation is analysed. Under suitable conditions this process, properly normed, has a weak limit as N becomes large. For the Wright-Fisher model this limit is an Ornstein–Uhlenbeck process (restricted to a discrete time-set). The corresponding stationary distributions of the backward processes converge to the normal distribution, as expected.
A representation for the limiting random variable of a branching process with infinite mean and some related problems
Authors: Cohn Harry , Pakes Anthony G. 
Published: July 2016

It is known that for a Bienaymé– Galton–Watson process {Zn
} whose mean m satisfies 1 &lt; m &lt; ∞, the limiting random variable in the strong limit theorem can be represented as a random sum of i.i.d. random variables and hence that convergence rate results follow from a random sum central limit theorem.
This paper develops an analogous theory for the case m = ∞ which replaces ‘sum' by ‘maximum'. In particular we obtain convergence rate results involving a limiting extreme value distribution. An associated estimation problem is considered.
Sequential rank and the Pólya urn
Authors: Robbins Herbert , Whitehead John 
Published: July 2016

A sequence of independent, identically distributed random variables is observed. After a sample of m has been collected attention is fixed to a particular observation. In this paper the fluctuations of the rank of this observation, as sampling continues, will be studied.
The process can be modelled by a Pólya urn scheme, and new results are obtained which are of interest in both sequential rank and Pólya urn contexts.
Approximations to densities in geometric probability
Authors: Solomon H. , Stephens M. A. 
Published: July 2016

Many random variables arising in problems of geometric probability have intractable densities, and it is very difficult to find probabilities or percentage points based on these densities. A simple approximation, a generalization of the chi-square distribution, is suggested, to approximate such densities; the approximation uses the first three moments. These may be theoretically derived, or may be obtained from Monte Carlo sampling.
The approximation is illustrated on random variables (the area, the perimeter, and the number of sides) associated with random polygons arising from two processes in the plane. Where it can be checked theoretically, the approximation gives good results. It is compared also with Pearson curve fits to the densities.
Physical nearest-neighbour models and non-linear time-series. II Further discussion of approximate solutions and exact equations
Authors: Bartlett M. S. 
Published: July 2016

The approximate two- and three-dimensional solutions for spatial correlations, using the non-linear time-series approach for nearest-neighbour systems developed in my previous paper, are further discussed.
Orthogonal expansions for the correlation functions are also developed which determine with this approach, though so far only in principle, the exact solutions.
The waiting-time process of a queueing system with gamma-type input and blocking
Authors: Langaris C. 
Published: July 2016

In this work the first-come-first-served waiting-time process of a customer in a two-stage queueing network without intermediate waiting space is analysed. We assume that the arrivals follow the gamma distribution, the service times in the first stage are arbitrarily distributed, and the service times in the second stage are again of gamma type.
Connecting the waiting time of the (n + 1)th customer with that of the nth and locating the zeros of a certain function we derive expressions for the Laplace transform of the waiting-time distribution both in the transient and the steady state.