Experimental studies on the distribution of the sexes of Mercurialis perennis L.

1) In a beechwood, male shoots of Mercurialis perennis were more frequent than female shoots in canopy openings, while females were more frequent at treebases than in canopy openings. 2) Flowering shoots were more frequent than non-flowering in openings. 3) The pH, moisture and organic content of the soil were similar at treebases and openings. The light climate was similar in both habitats in April but greater in the openings in August. 4) Removal of canopies of Pteridium aquilinum and Rubus fruticosus, above populations of M. perennis, resulted in a greater increase in the numbers of male shoots than of female shoots. 5) These results suggest that male and female plants differ in numbers, or growth, in different woodland microhabitats and that these differences are correlated with the above-ground environment (e.g. light).

Studies in the marketing strategy of a U.K. producer of conveyor belts

Research was undertaken in the field of marketing strategy, its formulation and implementation in Dunlop Belting Division. Emphasis was placed on marketing channel strategy, but other strategies including product strategy were studied. The research has resulted in changes in management practice in the client organisation. The relevance of theories of company organisation, planning and strategy, and marketing channels was examined in the light of the research evidence. The technique of action-research was used to gain admittance to and effect change within the client organisation. Case study material was collected for subsequent analysis. The factors affecting marketing strategy formulation in the client organisation were studied. Both the external and the internal business environments were considered. The operation of the observed marketing channels was compared with channel theory. Market segmentation and penetration, and the selling and technical resources of the channels were analysed. Recommendations were made to (a) enlarge and resite the client's distribution unit to locate it centrally in England (b) use the resited unit to secure local advantage (c) obtain greater integration of field sales activities with and from the centre. A new ex-stock distribution unit was established. Improvements to the client's ex-stock marketing in Scotland were also recommended, including improvements to the Scottish distributor's stock control procedure, as well as to Dunlop-Distributor relationships at all levels. The influence of company organisation structure and formalised procedures and systems on the formulation of strategy were considered with respect to channel and product strategy, and other aspects of marketing. Conclusions were drawn that the action research resulted in successful implementation of .agreed changes in the client organisation; that theories of strategy formulation and planning, of the operation of decentralised companies, and of industrial market segmentation required modification; that the theory of marketing channels was found relevant and useful.

Maximising the RFID benefits at the tyre distribution centre

In recent years the applications of radio frequency identification technology (RFID) in warehousing have gained a great amount of attention as it is a challenging and dynamic environment. Analysing a receiving operation of third party logistic (3PL) operator running a tyre distribution centre, this paper presents a case study of RFID application in the warehouse. The receiving process is enhanced with the RFID technology, which provides contactless identification, less manual data entry errors, instant stock management. Moreover, these benefits could be maximised by the proposed use of the RFID generated data in accounting of costs and services, which is a novel application of the RFID technology.

An examination of the calcium and strontium site distribution in bioactive glasses through isomorphic neutron diffraction, X-ray diffraction, EXAFS and multinuclear solid state NMR.

Strontium has been substituted for calcium in the glass series (SiO2)49.46(Na2O)26.38(P2O5)1.07(CaO)23.08x(SrO)x (where x = 0, 11.54, 23.08) to elucidate their underlying atomic-scale structural characteristics as a basis for understanding features related to the bioactivity. These bioactive glasses have been investigated using isomorphic neutron and X-ray diffraction, Sr K-edge EXAFS and solid state 17O, 23Na, 29Si, 31P and 43Ca magic-angle-spinning (MAS) NMR. An effective isomorphic substitution first-order difference function has been applied to the neutron diffraction data, confirming that Ca and Sr behave in a similar manner within the glass network, with residual differences attributed to solely the variation in ionic radius between the two species. The diffraction data provides the first direct experimental evidence of split Ca–O nearest-neighbour correlations in these melt quench bioactive glasses, together with an analogous splitting of the Sr–O correlations; the correlations are attributed to the metal ions correlated either to bridging or to non-bridging oxygen atoms. Triple quantum (3Q) 43Ca MAS NMR corroborates the split Ca–O correlations. Successful simplification of the 2 < r (A) < 3 region via the difference method has also revealed two distinct Na environments. These environments are attributed to sodium correlated either to bridging or to nonbridging oxygen atoms. Complementary multinuclear MAS NMR, Sr K-edge EXAFS and X-ray diffraction data supports the structural model presented. The structural sites present will be intimately related to their release properties in physiological fluids such as plasma and saliva, and hence the bioactivity of the material. Detailed structural knowledge is therefore a prerequisite for optimising material design.

Novel real-time homodyne coherent receiver using a feed-forward based carrier extraction scheme for phase modulated signals

We report a novel real-time homodyne coherent receiver based on a DPSK optical-electrical-optical (OEO) regenerator used to extract a carrier from carrier-less phase modulated signals based on feed-forward based modulation stripping. The performance of this non-DSP based coherent receiver was evaluated for 10.66Gbit/s BPSK signals. Self-homodyne coherent detection and homodyne detection with an injection-locked local oscillator laser was demonstrated. The performance was evaluated by measuring the electrical signal-to-noise (SNR) and recording the eye diagrams. Using injection-locking for the LO improves the performance and enables homodyne detection with optical injection-locking to operate with carrier-less BPSK signals without the need for polarization multiplexed pilot-tones.

Income distribution dependence of poverty measure:a theoretical analysis

Using a modified deprivation (or poverty) function, in this paper, we theoretically study the changes in poverty with respect to the 'global' mean and variance of the income distribution using Indian survey data. We show that when the income obeys a log-normal distribution, a rising mean income generally indicates a reduction in poverty while an increase in the variance of the income distribution increases poverty. This altruistic view for a developing economy, however, is not tenable anymore once the poverty index is found to follow a pareto distribution. Here although a rising mean income indicates a reduction in poverty, due to the presence of an inflexion point in the poverty function, there is a critical value of the variance below which poverty decreases with increasing variance while beyond this value, poverty undergoes a steep increase followed by a decrease with respect to higher variance. Identifying this inflexion point as the poverty line, we show that the pareto poverty function satisfies all three standard axioms of a poverty index [N.C. Kakwani, Econometrica 43 (1980) 437; A.K. Sen, Econometrica 44 (1976) 219] whereas the log-normal distribution falls short of this requisite. Following these results, we make quantitative predictions to correlate a developing with a developed economy. © 2006 Elsevier B.V. All rights reserved.

Two-dimensional optical power distribution of side-out-coupled radiation from tilted FBGs in multimode fibre

Two-dimensional optical power distribution of the out-coupled radiation from UV-inscribed tilted fibre Bragg gratings (TFBG) in multimode fibre (MMF) has been side-detected with high spatial spectral resolution, showing a near-identical radiation mode profile to that measured from the fibre-end detection method. A comparative investigation of the radiation characteristics of TFBGs fabricated in singlemode fibre (SMF) and MMF clearly indicates that the radiation out-coupling is stronger and spatially more confined in MMF. The unique spatial-to-spectral encoding property of the coupling mechanism offers potential application in low-cost WDM devices.

Statnote 37 : the negative binomial distribution

An organism living in water, and present at low density, may be distributed at random and therefore, samples taken from the water are likely to be distributed according to the Poisson distribution. The distribution of many organisms, however, is not random, individuals being either aggregated into clusters or more uniformly distributed. By fitting a Poisson distribution to data, it is only possible to test the hypothesis that an observed set of frequencies does not deviate significantly from an expected random pattern. Significant deviations from random, either as a result of increasing uniformity or aggregation, may be recognized by either rejection of the random hypothesis or by examining the variance/mean (V/M) ratio of the data. Hence, a V/M ratio not significantly different from unity indicates a random distribution, greater than unity a clustered distribution, and less then unity a regular or uniform distribution . If individual cells are clustered, however, the negative binomial distribution should provide a better description of the data. In addition, a parameter of this distribution, viz., the binomial exponent (k), may be used as a measure of the ‘intensity’ of aggregation present. Hence, this Statnote describes how to fit the negative binomial distribution to counts of a microorganism in samples taken from a freshwater environment.

When do incentives work in channels of distribution?

The incentive dilemma refers to a situation in which incentives are offered but do not work as intended. The authors suggest that, in an interorganizational context, whether a principal-provided incentive works is a function of how it is evaluated by an agent: for its contribution to the agent's bottom line (instrumental evaluation) and for the extent it is strategically aligned with the agent's direction (congruence evaluation). To further understand when incentives work, the influence of two key contextual variables-industry volatility and dependence-are examined. A field study featuring 57 semi-structured depth interviews and 386 responses from twin surveys in the information technology and brewing industries provide data for hypothesis testing. When and whether incentives work is demonstrated by certain conditions under which the agent's evaluation of an incentive has positive or negative effects on its compliance and active representation. Further, some outcomes are reversed in the high volatility condition. © 2013 Academy of Marketing Science.

A unidirectional scheme for high-fidelity optical-carrier dissemination using phase-modulation, homodyne coherent-detection, and frequency entrainment

We report for the first time an ultra-stable optical-carrier dissemination technique for transmission over a 20km unidirectional fibre link. The optical-linewidth of the recovered carrier matches closely that of the original carrier. © 2014 OSA.

Multiple criteria optimization of contemporary logistics distribution network problems

In the contemporary customer-driven supply chain, maximization of customer service plays an equally important role as minimization of costs for a company to retain and increase its competitiveness. This article develops a multiple-criteria optimization approach, combining the analytic hierarchy process (AHP) and an integer linear programming (ILP) model, to aid the design of an optimal logistics distribution network. The proposed approach outperforms traditional cost-based optimization techniques because it considers both quantitative and qualitative factors and also aims at maximizing the benefits of deliverer and customers. In the approach, the AHP is used to determine the relative importance weightings or priorities of alternative warehouses with respect to some critical customer-oriented criteria. The results of AHP prioritization are utilized as the input of the ILP model, the objective of which is to select the best warehouses at the lowest possible cost. In this article, two commercial packages are used: including Expert Choice and LINDO.

Experimental and theoretical study of longitudinal power distribution in a random DFB fiber laser

We have measured the longitudinal power distribution inside a random distributed feedback Raman fiber laser. The observed distribution has a sharp maximum whose position depends on pump power. The spatial distribution profiles are different for the first and the second Stokes waves. Both analytic solution and results of direct numerical modeling are in excellent agreement with experimental observations. © 2012 Optical Society of America.

Evaluation of Pareto/D/1/k Queue by Simulation

The finding that Pareto distributions are adequate to model Internet packet interarrival times has motivated the proposal of methods to evaluate steady-state performance measures of Pareto/D/1/k queues. Some limited analytical derivation for queue models has been proposed in the literature, but their solutions are often of a great mathematical challenge. To overcome such limitations, simulation tools that can deal with general queueing system must be developed. Despite certain limitations, simulation algorithms provide a mechanism to obtain insight and good numerical approximation to parameters of queues. In this work, we give an overview of some of these methods and compare them with our simulation approach, which are suited to solve queues with Generalized-Pareto interarrival time distributions. The paper discusses the properties and use of the Pareto distribution. We propose a real time trace simulation model for estimating the steady-state probability showing the tail-raising effect, loss probability, delay of the Pareto/D/1/k queue and make a comparison with M/D/1/k. The background on Internet traffic will help to do the evaluation correctly. This model can be used to study the long- tailed queueing systems. We close the paper with some general comments and offer thoughts about future work.