• Title/Summary/Keyword: Ph.D

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Citation Analysis of PhDs Awarded in Public Administration and Political Science by Punjabi University Patiala

  • Rattan, Gurjeet Kaur;Singh, Jagtar
    • International Journal of Knowledge Content Development & Technology
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    • v.12 no.2
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    • pp.41-56
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    • 2022
  • This research paper presents the use of different forms of literature by the PhD researchers of the Department of Political Science and the Department of Public Administration, Punjabi University, Patiala. It is assessed by analyzing the resources cited in the PhD theses awarded by Punjabi University, Patiala during 2015-2019. The different bibliographic forms of the references have been analyzed in order to find out the year-wise submission, average citations per thesis, authorship pattern, chronology, use of electronic resources, and format of citations in both the subjects under study. It has been found in this study that average citations per thesis in Political Science is more (200.53) than Public Administration (160.6). Books are most preferred form in both the subjects. Majority of the citations in both the subjects are from the period 2000-2009. Ranked list of journals for both the subjects have been prepared to identify core journals. The core journals in both the subjects are 9. Bradford Multipliers have been calculated and application of Bradford Law of Scattering has also been tested for both the subjects. It is expected that the present study will help librarians in selecting, retaining and cancelling the existing journals in Political Science and Public Administration.

Amine Donors in Nonlinear Optical Molecules: Methyl and Phenyl Substitution Effects on the First Hyperpolarizability

  • Park, Gyoo-Soon;Ra, Choon-Sup;Cho, Bong-Rae
    • Bulletin of the Korean Chemical Society
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    • v.24 no.11
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    • pp.1671-1674
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    • 2003
  • The effects of amine donors ($a:NH_2,\;b:NMe_2,\;c:NMePh,\;d:NPh_2$) and conjugation length on the molecular hyperpolarizabilities of a series of dipolar molecules have been theoretically investigated by using CPHF/6-31G method. The first hyperpolarizabilities (${\beta}$) of p-nitrobenzene derivatives increase with the donor in the order, $NH_2\;<\;NMe_2\;<\;NMePh\;<\;NPh_2$, whereas slightly different order is observed in more conjugated derivatives, i.e., $NH_2\;<\;NPh_2\;<\;NMe_2\;<\;NMePh$. The result has been attributed to the extent of charge transfer and torsion angle. Moreover, the results show that "non-traditional" ${\pi}$-conjugation effect exists in small compounds and decreases as the conjugation length between donor and acceptor increases.

Performance Analysis of Photonic Crystal Enhanced Micro-Combustor Thermophotovoltaic System for Drone Application (광결정 표면을 이용한 드론용 마이크로 연소기 열광전 에너지변환시스템의 성능해석)

  • Lee, Junghun
    • Journal of the Korea Institute of Military Science and Technology
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    • v.24 no.3
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    • pp.309-316
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    • 2021
  • In this paper, the electrical power output of the micro-combustor thermophotovoltiac(TPV) system was analyzed. The system consists of a micro-combustor, photonic crystals(PhCs), and photovoltaic cells(PV cells). The system has a micro-combustor that can achieve over 1,000 K surface temperature by consuming 2.5 g/h hydrogen fuel. Also, this system incorporates current state-of-the-art PhCs surfaces(2D Ta PhCs and Tandem Filter) to increase electrical power output. In addition, InGaAsSb PV cell, which bandgap is 0.55 eV, was applied to convert a wide range of radiative energy. The performance analysis shows that a single micro-combustor TPV system can produce 0.4 W ~ 27.7 W electrical power with the temperature change of emitter(900 K ~ 1,500 K) and PV cell(250 K ~ 400 K).

A Study on the Nitrogen Permeation Treatment of 17-4 PH Stainless Steel (17-4 PH Stainless 강의 질소침투 열처리)

  • Yoo, D.K.;Sung, J.H.
    • Journal of the Korean Society for Heat Treatment
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    • v.19 no.2
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    • pp.83-89
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    • 2006
  • The surface phase changes, the hardness variations, the nitrogen contents and the corrosion resistances of 17-4 PH stainless steel have been investigated after nitrogen permeation(solution nitriding) at a temperature ranges from $1050^{\circ}C$ to $1150^{\circ}C$ The phases appeared at the nitrogen-permeated surface layer were shown to martensite plus austenite and austenite, depending on the variation of nitrogen and chromium contents. And the surface hardness was also depended on the phases appeared at the surface layer from 370 Hv to 220 Hv. The precipitates exhibited at the nitrogen-permeated surface layer were niobium nitride, niobium chromium nitride and carbo-nitride in the austenite and martensite matrices. The surface nitrogen contents were followed by the Cr contents of the surface layers, representing 0.55% at the temperatures of $1050^{\circ}C$ and $1150^{\circ}C$ respectively, and 0.96% at $1100^{\circ}C$ at the distances of $60{\mu}m$ from the outmost surface. From the comparison of the corrosion resistances between nitrogen-permeated and solution-annealed steels, nitrogen permeation remarkably improved the corrosion resistance in the solution of 1 N $H_2SO_4$ due to the increase of nitrogen content in the surface austenite phase.