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1.
Soil science is a relatively young and specialised field of science. This note discusses the use of the h index as a scientific output measure in soil science. We explore the governing factors of h index in soil science: the number of soil scientists, the number of papers published, the average number of citations, and the age of the scientist. We found the average relationship between h index and scientific age for soil science: h = 0.7 t. The h index for soil science is smaller than other major science disciplines but norms for h need to be established  相似文献   

2.
Journals covered by the 2006 Science Citation Index Journal Citation Reports database have been subjected to a clustering procedure utilizing h-similarity as the underlying similarity measure. Clustering complemented with a prototyping routine provided well-conceivable results that are both compatible with and further refine existing taxonomies of science.  相似文献   

3.
To be able to measure the scientific output of researchers is an increasingly important task to support research assessment decisions. To do so, we can find several different measures and indices in the literature. Recently, the h-index, introduced by Hirsch in 2005, has got a lot of attention from the scientific community for its good properties to measure the scientific production of researchers. Additionally, several different indicators, for example, the g-index, have been developed to try to improve the possible drawbacks of the h-index. In this paper we present a new index, called hg-index, to characterize the scientific output of researchers which is based on both h-index and g-index to try to keep the advantages of both measures as well as to minimize their disadvantages.  相似文献   

4.
Except the alphabetic ordering authorship papers, the citations of multi-authored papers are allocated to the authors based on their contributions to the paper. For papers without clarification of contribution proportion, a function of author number and rank is presented to rightly determine the credit allocated proportion and allocated citations of each author. Our citation allocation scheme is between the equally fractional counting and the one using the inverse of author rank. It has a parameter to adjust the credit distribution among the different authors. The allocated citations can either be used alone to indicate one’s performance in a paper, or can be applied in the modification of h-index and g-index to represent the achievement of a scientist on the whole. The modified h-index and g-index of an author makes use of more papers in which he or she played important roles. Our method is suitable for the papers with wide range of author numbers.  相似文献   

5.
The objective of this research is to develop a new patent bibliometric performance measure by using modified citation rate analyses with dynamic backward citation windows. Cited half-life employed in bibliometrics was adopted in order to establish a model of annual patent backward citation windows. Based on the dynamic behavior of backward citation windows, the annual backward patent citation rates for each technology domain can be calculated to measure its bibliometric performance. It was found that the dynamic backward citation window represents more accurately the citation cycle time which is a key factor on technology assessment. Because different technology domain may have disparate attributes, a normalized backward citation rate was developed to measure the corresponding rank for each domain respect to the entire industry. Three technology domains were then chosen for demonstrative case studies which represent semiconductor, LCD, and drug industries.  相似文献   

6.
Data on sound velocity are used for determining the density, the isobaric expansion coefficient, the isobaric and isochoric heat capacity, and the isothermal compressibility of liquid binary mixture of n-decane + n-hexadecane of three compositions in the temperature range of 298–433 K and pressure range of 0.1–100 MPa. The coefficients of Tait equation are calculated in the above-identified range of parameters. The calculation results are compared with experimental data on density. The divergence does not exceed 0.2% for the most reliable data.  相似文献   

7.
We have studied the electrical characteristics of photodiodes based on p-GaSb/p-GaInAsSb/N-GaAlAsSb heterojunctions and investigated the mechanisms of current transfer in these heterostructures at various temperatures. A comparison of the theoretical results and experimental data showed that the tunneling charge transfer mechanism dominates at low temperatures (T < 150 K) under both forward and reverse bias conditions. The tunneling current becomes a determining factor at an electric field strength in the p-n junction of no less that 105 V/cm, which is related to a small bandgap width of the materials studied and low effective masses of electrons and holes.  相似文献   

8.
Summary Hirsch (2005) has proposed the h-index as a single-number criterion to evaluate the scientific output of a researcher (Ball, 2005): A scientist has index h if h of his/her Np papers have at least h citations each, and the other (Nph) papers have fewer than h citations each. In a study on committee peer review (Bornmann & Daniel, 2005) we found that on average the h-index for successful applicants for post-doctoral research fellowships was consistently higher than for non-successful applicants.  相似文献   

9.
The h-index and Eigenfactor TM values of top and specialized scientific/engineering journals are tabulated and combined to provide a simple graphical representation of the journals. The information may be tailored to specific uses by respective stakeholders to aid decision making processes with regards to scholarly research and scientific journal publications.  相似文献   

10.
Gad Saad 《Scientometrics》2010,83(2):423-433
The h-index is a recent metric that captures a scholar’s influence. In the current work, it is used to: (1) obtain the h-index scores of the most productive scholars in the Journal of Consumer Research (JCR), and compare these to other elite scholars (including those of the other three premier marketing journals); (2) demonstrate the relationship between the h-indices and total number of citations of the top JCR producers; (3) examine the h-indices of Ferber winners (best interdisciplinary paper based on a doctoral dissertation published in JCR in a given year) and those having received honorable mentions; (4) explore the relationship between a marketing journal’s prestige and the corresponding h-index score of its editor. These varied analyses demonstrate the multitudinous ways in which the h-index can be used when investigating bibliometric phenomena within a given discipline.  相似文献   

11.
12.
The existence of an SH-wave incidence angle for which the reflected amplitude is zero (SH-wave intromission angle) is established for the case of plane-wave scattering by a planar interface joining two homogeneous, isotropic, and linearly elastic half-spaces. Such an incidence angle is numerically shown to exist for two combinations of bimaterial interface properties. The SH-wave intromission angle is roughly parallel to the electromagnetic Brewster angle and the acoustic P-wave intromission angle, and the concept should find new applications for non-intrusive characterization of interfaces.  相似文献   

13.
The electrical characteristics of (p)3C-SiC-(n)6H-SiC epitaxial heterostructures obtained by sublimation epitaxy in vacuum are studied. The band discontinuities are determined and the energy band diagram of the heterojunction is constructed. It is shown that the obtained heterostructure offers a promising material for high electron mobility transistors.  相似文献   

14.
The problem of comparing academic institutions in terms of their research production is nowadays a priority issue. This paper proposes a relative bidimensional index that takes into account both the net production and the quality of it, as an attempt to provide a comprehensive and objective way to compare the research output of different institutions in a specific field, using journal contributions and citations. The proposed index is then applied, as a case study, to rank the top Spanish universities in the fields of Chemistry and Computer Science in the period ranging from 2000 until 2009. A comparison with the top 50 universities in the ARWU rankings is also made, showing the proposed ranking is better suited to distinguish among non-elite universities.  相似文献   

15.
The MNS1100 precision RLC-meter, which operates over a wide range of frequencies and measurable impedance parameters, is described. The instrument is based on new impedance measuring principles with a reduced set of measures and methods of calibrating the measuring circuits, which enable the measurement accuracy to be increased considerably, extend the functional capabilities and automate the apparatus adjustment.  相似文献   

16.
17.
The gravireception of the fungus Phycomyces blakesleeanus and seedlings of Arabidopsis thaliana is accompanied by gravity-induced absorption changes (GIACs) that occur very fast and most likely represent primary responses of gravireception. GIACs that were analyzed during parabolic flights in micro- and hypergravity invariably display hysteretic behavior. Even though the identity of the pigments generating the GIACs remain presently unknown, it is nevertheless clear that they are specific for gravireception. This is strongly suggested by the fact that hystereses loops of wild-type specimen are significant larger than of gravitropic mutants. Hystereses are largely kinetically determined, are specific for the different organisms and stimulus programs, and thus aid in characterizing the requisite transduction chains of gravireception. The fact that monocot as well as dicot plants display GIACs just in the area of highest gravitropic sensitivity at the tip supports the conclusion that gravireception is generally associated with primary reactions.  相似文献   

18.
In this paper, we present some examples of sensitivity analysis for flows modeled by the standard kε model of turbulence with wall functions. The flow and continuous sensitivity equations are solved using an adaptive finite element method. Our examples emphasize a number of applications of sensitivity analysis: identification of the most significant parameters, analysis of the flow model, assessing the influence of closure coefficients, calculation of nearby flows, and uncertainty analysis. The sensitivity parameters considered are closure coefficients of the turbulence model and constants appearing in the wall functions.  相似文献   

19.
20.
Temperature dependence of d.c. conductivity is studied ina- Se75In25-x Pb x thin films wherex is varied from 0–10. From these measurements, the values of the pre-exponential factor (σ0) and activation energy (ΔE) are calculated for each glassy alloy. An approximate linear dependence of ln σ0 on AE is observed in this glassy system with good agreement between the expected and calculated σ0 values using Meyer-Neldel rule. Linear dependence of ln σ0 on ΔE in case of amorphous materials indicates that the conduction band tails a finite energy distance towards the valence band and Fermi level is controlled by fixed dominant hole levels deeper in the gap.  相似文献   

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