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Research Output of the Pakistani Library and Information Science Authors: A Bibliometric Evaluation of Their Impact

  • Anwar, Mumtaz Ali;Jan, Sajjad Ullah
    • Journal of Information Science Theory and Practice
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    • v.5 no.2
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    • pp.48-61
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    • 2017
  • This paper uses 601 cited papers of Pakistani LIS researchers with the purpose to examine the individual performance of these Library and Information Science (LIS) researchers in terms of their research output and its impact on the LIS (national/international) literature by using various bibliometric indicators. A list of 139 authors was compiled with the help of the Library, Information Science, and Technology Abstracts (LISTA) and some other sources. Data were collected from Google Scholar and SPSS version 20 was utilized in order to identify the relationship between self-citations and various performance indices of the authors. The average citations received per paper vary from 1.80 to 10.08. About half of the papers were single-authored whereas less than one-fifth were by three or more authors. The authors who worked in collaboration produced more papers and received more citations. The h-index, g-index, hI-index, hI-norm, and e-index were used to determine the rank for each author. The intra-group citations grid revealed the volume of self-citations and a small group who cite each other more due to close academic and social relationships. The correlations between self-citations and the impact indices used revealed significant differences. Findings are useful for concerned institutions regarding award, promotions, etc. Further, future research should seriously consider the self-citations and social networking of authors while examining their citations-based research performance.

Post-pillars design for safe exploitation at Trepça hard rock mine (Kosovo) based on numerical modeling

  • Ibishi, Gzim;Genis, Melih;Yavuz, Mahmut
    • Geomechanics and Engineering
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    • v.28 no.5
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    • pp.463-475
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    • 2022
  • In the mine exploitation stage; one of the critical issues is the stability assessment of post-pillars. The instability of post-pillars leads to serious safety hazards in mining operations. The focus of this study is to assess the stability of post-pillars in the 130# stope in the central ore body at Trepça hard rock mine by employing both conventional (i.e., critical span curve) and numerical methods (i.e., FLAC3D). Moreover, a new numerical based index (i.e., Pillar Yield Ratio-PYR) was proposed. The aim of PYR index is to determine a border line between stable, potentially unstable, and failure state of post-pillars at a specific mine site. The critical value of pillar width to height ratio is 2.5 for deep production stopes (e.g., > 800 m). Results showed that pillar size, mining height and mining depth significantly have affected the post-pillar stability. The reliability of numerical based index (i.e., PYR) is verified based on empirical underground pillar stability graph developed by Lunder, 1994. The proposed pillar yield ratio index and pillar stability graph can be used as a design tool in new mining areas at Trepça hard rock mine and for other situations with similar geotechnical conditions.

Synthesis and Thermal Property of Poly(styrene-g-caprolactone) with Well-defined Structure (분자구조가 제어된 Poly(styrene-g-caprolactone)의 합성 및 그라프트 공중합체의 열적 성질)

  • 오병석;안성국;조창기
    • Polymer(Korea)
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    • v.24 no.3
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    • pp.306-313
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    • 2000
  • Polycaprolactone (PCL) macromer containing terminal methacrylate group was synthesized by ring-opening polymerization. The number average molecular weight of PCL macromer was 11600 g/mole and polydispersity index was 1.09. The synthesized PCL macromer was copolymerized with styrene by stable free radical polymerization using 2,2,6,6-tetramethyl-1-piperidinyloxy (TEMPO), benzoyl peroxide, and well-defined poly(styrene-g-caprolactone)s were synthesized. The synthesized copolymers was characterized by $^1$H-NMR and gel permeation chromatography equipped with multiangle laser light scattering detector. Thermal properties of graft copolymers were investigated by DSC.

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A Study on the Mechanical Properties of the Cretaceous Tuffs in Goheung Area. (고흥지역에 분포하는 백악기 응회암의 역학적 특성에 관한 연구)

  • Kim Hai-Gyoung;Koh Yeong-Koo;Oh Kang-Ho
    • The Journal of Engineering Geology
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    • v.14 no.3 s.40
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    • pp.273-285
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    • 2004
  • The mechanical properties of the Cretaceous tuff distributed in the Goheung area were measured in the laboratory. Tuff (Goehung tuff and Palyeongsan welded tuff) in the study area is classified into vitric tuff with regard to its composition. The specific gravity, the dry density, the water content, the porosity and absorption ratio in tuffs of the study area are 2.51, $2.52(g/cm^2)$, 0.12($\%$), 4.51($\%$) and 1.91($\%$) in means, respectively. In the tuffs, dry densities are in inverse Proportion to Porosities, and absorption ratios are highly proportional with Porosities. The uniaxial compressive strengths(UCS) in the tuffs ranges from 80.4 to 208(MPa) and the average of the strength is 141.1(MPa). According to the engineering classification of intact rock (Deere & Miller, 1966), the tuffs are assigned to the high strength rocks. The point load strength index ($Is_a$) in axial test is 4.2(MPa) on the average, and the point load strength index ($Is_d$) in diametral test is 2.2(MPa) in mean, and the point load strength anisotrophic index($Ia_{(50)}$) by the ratio of $Is_a$ to $Is_d$ is 1.93. There is close linear correlation between the uniaxial compressive strength and point load strength index, and the equation representing the correlation is postulated as follows : UCS = 22 $Is_{(50)}$ +49 (MPa) (r=0.95). It is considered that this equation is a useful tool to estimate UCS for tuff in Goheung area.

Antagonistic Interaction between Quinclorac and Bensulfuron-methyl on Growth of the Rice Plants (Quinclorac과 Bensulfuron-methyl의 혼합처리(混合處理)에서 벼의 생장(生長)에 대한 제초제간(除草劑間) 길항작용(拮抗作用))

  • Kwon, Oh-Yeon;Kwon, Yong-Woong
    • Korean Journal of Weed Science
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    • v.17 no.3
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    • pp.288-294
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    • 1997
  • Field and pot expeiments were carried out to evaluate the interaction between quinclorac and bensulfuron-methyl on growth of the rice plants(Oryza sativa L. cv. Choocheongbyeo) at 20, 45, 65 days-old stages. Quinclorac and bensulfuron-methyl showed antagonistic interaction at both stages, which were detected by the Chisaka's method at isobles of 10% growth inhibition. The antagonism indices were -0.63 and -1.67 at 20 and 65 days-old seedling stages, respectively. Leaf-rolling of rice occurred when quinclorac was applied at 600g ai/ha or more at 20 days-old seedling stage, while it occured at the dose of 900g ai/ha at 65 days-old stage. Bensulfuron-methyl reduced plant height and dry weight as well as tiller production at both stages. Leaf-rolling of rice was reduced when mixture of quinclorac and bensulfuron-methyl was applied due to antagonism of the two herbicides. High temperatures increased the phytotoxicity of bensulfuron-methyl, while the phytotoxicity caused by quinclorac alone was not responsive to temperature. The antagonistic effect between quinclorac and bensulfuron-methyl increased at low temperature as tested by the Colby's method.

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Evaluation of quality index of salted Korean cabbage in the short-term distribution system (절임배추의 단기 유통 품질지표 평가)

  • Kim, Min-Jung;Song, Hye-Yeon;Park, Sang-Un;Chun, Ho Hyun;Han, Eung Soo;Chung, Young-Bae
    • Food Science and Preservation
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    • v.24 no.1
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    • pp.36-43
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    • 2017
  • The aim of this study was to provide the quality index of salted Korean cabbage in a short-term distribution system. Salted Korean cabbages were packaged with or without 2% salt water, and then distributed in a conventional system (CVS) and a cold-chain system (CCS) for 6 h. The material temperature of samples with and without salt water gradually increased to $19.57^{\circ}C$ and $19.43^{\circ}C$ in a CVS, respectively and to $10.73^{\circ}C$ and $12.90^{\circ}C$ in a CCS, respectively. Salinity of the materials in a CCS did not change, whereas salinities of the materials in a CVS were 1.2 and 1.7 fold higher, respectively. Also, a slight increase in acidity was observed in both packaging materials in a CCS. In the case of a CVS, total aerobic bacteria and lactic acid bacteria increased to 7.62 log CFU/g and 6.77 log CFU/g in the materials with salt water, respectively, whereas the number of total aerobic bacteria and lactic acid bacteria ranged between 5.62-5.85 log CFU/g and 4.33-4.83 log CFU/g in the materials without salt water, respectively. However, significant microbial changes were not observed in a CCS as distribution time increased. CCS with salt water packaging was effective in achieving microbial control and maintaining physicochemical quality. Salinity, aerobic bacteria, and lactic acid bacteria can be useful as quality indices for a CVS, and acidity can be useful as quality index for a CCS.

A Polynomial Time Algorithm for Edge Coloring Problem (간선 색칠 문제의 다항시간 알고리즘)

  • Lee, Sang-Un
    • Journal of the Korea Society of Computer and Information
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    • v.18 no.11
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    • pp.159-165
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    • 2013
  • This paper proposes a O(E) polynomial-time algorithm that has been devised to simultaneously solve edge-coloring problem and graph classification problem both of which remain NP-complete. The proposed algorithm selects an edge connecting maximum and minimum degree vertices so as to determine the number of edge coloring ${\chi}^{\prime}(G)$. Determined ${\chi}^{\prime}(G)$ is in turn either ${\Delta}(G)$ or ${\Delta}(G)+1$. Eventually, the result could be classified as class 1 if ${\chi}^{\prime}(G)={\Delta}(G)$ and as category 2 if ${\chi}^{\prime}(G)={\Delta}(G)+1$. This paper also proves Vizing's planar graph conjecture, which states that 'all simple, planar graphs with maximum degree six or seven are of class one, closing the remaining possible case', which has known to be NP-complete.