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Summary  

Based on the transform function model of the observed citing process, the analytical expression of the age distribution of citations is deduced, and it is theoretically proved that the peak value of the citation distribution curve would fall and shift backward along with increasing the average publication delay and the peak age has a direct proportion relation with the pure delay and would be prolonged along with increasing the delay or decreasing the aging rate. The influence of the average publication delay on three ISI indicators impact factor, immediacy index and cited half-life are studied; in one subject discipline, the bigger the delay, the lower the three indicators of journals. Using the sensitivity theory, sensitivity formulae of the three indicators to publication delay parameters are deduced and it is found that responses of these indicators to changes of publication delays are different according to different time constant of the aging process; The faster the aging rate of a discipline literature is, the worse the influence of publication delays on the indicators of journals in the discipline.

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Abstract  

Some new linear and nonlinear delay integral inequalities of G-B-B type are obtained which generalize some results of O. Akinyele [1], P. Ch. Tsamatos and S. K. Ntouyas [16]. Application examples are also given.

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Based on the convolution formula of the disturbed aging distribution (Egghe&Rousseau, 2000) and the transfer function model of the publishing delay process, we establish the transfer function model ofthe disturbed citing process. Using the model, we make simulative investigations of disturbed citation distributions and impact factors according to different average publication delays. These simulative results show that the bigger increment the average publication delays in a scientific field, the larger shift backwards of the citation distribution curves and the more fall the impact factors of journals in the field. Based on sometheoretical hypotheses, it is shown that there exists theoretically an approximate inverse linear relation between the field (or discipline) average publication delay and the journal impact factor.

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Abstract  

In this paper, the internal law of delay in the secondary literature publishing process is presented. The process is demonstrated to abide by the partial differential equation of periodical literature publishing process. A definite solution of the publishing delay process is derived. Accordingly, the expression of average publication delay indicator based on the particular solution is deduced. Then the problem is studied that some information of primary literatures is missed in information retrieval, and the relationship is established between the average delay indicator and the miss ratio of primary literatures in the index periodicals or databases. Also it is proposed that the primary literature should be used as a supplemental tool in information retrieval to guarantee the recall ratio.

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Summary According to the discrete model of periodical publication process, recurrence formulae of parameters of the process are gained and the initial conditions of control process parameters from one steady state to another are deduced. Using the variable separation approach, which is used generally to solve the partial differential equation, the recurrence computing formula of the publication probability function is deduced. First the publication delay increasing process caused by the accepted contribution flux increase is simulated, and then the publication delay decreasing processes under four different control means are simulated too. Finally it is demonstrated that the periodical publishing process is a strong inertia system and it is found that reducing the quantity of deposited contributions can shorten the publication delay.

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In this paper we establish some new integral inequalities with delay, which can be used as tools in the theory of some new classes of differential and integral equations. An application to obtain a bound on the solution of a certain integral equation is also given.

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In our paper we investigate the unbiased movement of the unicellular eukaryotic ciliate Tetrahymena Pyriformis. We use a time-delayed version of the previously known model to describe the specific movement of this species. With the help of semi-discretization, we state analytic results for the model.

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., Singh, U. P. (1992) Morphometric changes in the ovaries of Indian vespertilionid bat, Scotophilus heathi with reference to delayed ovulation. Eur. Arch. Biol. 103 , 257-264. Morphometric changes in the ovaries of Indian

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Abstract  

The cascade process of decay of most radionuclides with corpuscular and photon radiation (β-α, α-ψ, β-ψ, ψ-ψ, α-x, β-x) with an average life-time of the intermediate states from 10−10 to some 10 sec, makes it possible to use the delayed coincidence method for selective analysis. Natural mixtures of radionuclides were analyzed for isotopes214Bi(RaC),212Bi(ThC),219Rn(An) and220Rn(TN)with the aid of instruments including scintillation detectors and a multichannel time selector by using β-α and α-α delayed coincidences, while isotopic ratio235U/235U in natural uranium was determined by using α-ψ coincidences. The instrument background did not exceed 1 pulse per hour per coincidence channel. Subjected to analysis were rocks with Clarks of radioactive elements.

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Abstract  

The predominant use of the nuclear track technique (NTT) in analytical chemistry has been to measure the prompt charged particle emission from neutron induced reactions with stable or fissile nuclides of selected elements. This work describes the use of the NTT for determining bismuth via delayed alpha particle emission from the decay of210P. This technique is sensitive and reliable since alpha track counting is highly efficient and can provide information, on elemental spatial distributions. Bismuth determinations in various materials by this technique appears possible to at least the 1.0 microgram per gram level.

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