• Title/Summary/Keyword: PI index

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THE MULTIPLICATIVE VERSION OF WIENER INDEX

  • Hua, Hongbo;Ashrafi, Ali Reza
    • Journal of applied mathematics & informatics
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    • v.31 no.3_4
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    • pp.533-544
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    • 2013
  • The multiplicative version of Wiener index (${\pi}$-index), proposed by Gutman et al. in 2000, is equal to the product of the distances between all pairs of vertices of a (molecular) graph G. In this paper, we first present some sharp bounds in terms of the order and other graph parameters including the diameter, degree sequence, Zagreb indices, Zagreb coindices, eccentric connectivity index and Merrifield-Simmons index for ${\pi}$-index of general connected graphs and trees, as well as a Nordhaus-Gaddum-type bound for ${\pi}$-index of connected triangle-free graphs. Then we study the behavior of ${\pi}$-index upon the case when removing a vertex or an edge from the underlying graph. Finally, we investigate the extremal properties of ${\pi}$-index within the set of trees and unicyclic graphs.

The Theoretical Studies for the $\pi$-Binding Energy of Hydrocarbons Using the Molecular Connectivity (I) (Molecular Connectivity 법에 의한 탄화수소들의 $\pi$-결합에너지에 관한 이론적 연구 (제 1 보))

  • Ui Rak Kim;Jong Guk Eun;Myung-Jae Lee;Sang Hae Kim
    • Journal of the Korean Chemical Society
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    • v.31 no.2
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    • pp.143-152
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    • 1987
  • $\pi$-Binding energy of the 153 kinds of unsaturated acyclic polyenes and unsaturated cyclic polyenes has been calculated by the Kier's Molecular Connectivity Index. An excellent linear correlation is found between HMO $\pi$-binding energy and $\pi$-binding energy calculated by the Kier's Molecular Connectivity Index. In either class of unsaturated acyclic hydrocarbons and unsaturated cyclic hydrocarbon, the regression analysis reveals a highly significant linear correlation between $E_{\pi}$ and $^1{\chi}^v$ (the first order valence connectivity index).

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Variation Monoterpenes during Leaf Development in Ambrosia artemisiifolia var. elatior (돼지풀 잎의 성장기 동안 Monoterpenes 조성과 계절적 변이)

  • 김종희;김해수
    • The Korean Journal of Ecology
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    • v.22 no.3
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    • pp.155-161
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    • 1999
  • The plastochron index (PI) according to leaf development of Ambrosia artemisiifolia var. elatior were estimated. The amount and composition of monoterpenes in the leaves of A. artemisiifolia var. elatior were determined, and the seasonal monoterpene variations in representative of plastochron index were investigated. The total amount of monoterpenes in A. artemisiifolia var. elatior was increased continuously from PI 2.0, the highest amount was in PI 11.89. The major monoterpenes in A. artemisiifolia var. elatior consisted of 29 compounds. The leaf monoterpene fraction of A. artemisiifolia var. elatior were dominated by No.2, octene, α-pinene, β-myrcene, 1,3,6-octatrine, endo-borneol and (-)-bornyl acetate.

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Study on Environmental Monitoring in Stack Room for Paper Storage Using the Preservation Index (보존 환경 평가 지수를 이용한 종이 보존 서고 환경 모니터링 연구)

  • Shin, Hyun-Chang;Yoon, Man-Young
    • Journal of the Korean Graphic Arts Communication Society
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    • v.29 no.1
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    • pp.61-74
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    • 2011
  • Critical environmental elements for long term preservation of a paper are temperature, humidity, dust, light, contaminants in air, and mold. Especially, temperature and humidity need special care, because they can not only directly degrade paper but also affect the degradation of the other elements. Therefore methods to monitor variation of temperature and relative humidity were studied. One of the methods was to use preservation index for evaluating preservation environment. Since the evaluation for preservation environment of a stack room investigated firstly by D. K. Sebera, PI(preservation index) and TWPI(Time-Weighted Preservation Index) by IPI is made to evaluate relatively preservation environment in a stack room. T. Padfield developed method which could calculate easy PI and TWPI. In this study, the preservation environment of stack rooms for paper storage in NAK(National Archives Korea) was evaluated by PI and TWPI. PI and TWPI of stack rooms for paper storage in NAK maintained good condition but PI depended on season. Then the preservation environment of stack rooms for paper storage in NAK was required to maintain continuously PI and TWPI regardless of season change.

Improving the Perfectionism Index to Identify Influential Journals versus Mass Producers (완벽주의 지수 PI의 개량을 통한 유력 학술지와 대량생산 학술지의 구분)

  • Lee, Jae Yun
    • Journal of the Korean Society for information Management
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    • v.36 no.2
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    • pp.201-222
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    • 2019
  • The Perfectionism Index (PI) is an indicator that is recently proposed to distinguish influential researchers from mass producers. In this study, Near Perfectionism Index (NPI), an improved indicator of Perfectionism Index, can be a solution to the problem of PI that indiscriminately gives a penalty to all low-cited papers regardless of publishing time or other issues. NPI improved the method to give a penalty to tail complement area considering the citation distribution curve. It prevents the improvement of the h-index from adversely affecting the researcher's influence indicator. This study uses NPI to evaluate information and library science journals in Web of Science database. It successfully distinguishes between influential journals and mass producers unlike journal h-index or average citation frequency which could not differentiate influentials from mass producers.

THE VERTEX AND EDGE PI INDICES OF GENERALIZED HIERARCHICAL PRODUCT OF GRAPHS

  • Tavakoli, M.;Rahbarnia, F.
    • Journal of applied mathematics & informatics
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    • v.31 no.3_4
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    • pp.469-477
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    • 2013
  • Pattabiraman and Paulraja [K. Pattabiraman, P. Paulraja, Vertex and edge PI indices of the generalized hierarchical product of graphs, Discrete Appl. Math. 160 (2012) 1376- 1384] obtained exact formulas for the vertex and edge PI indices of generalized hierarchical product of graphs. The aim of this note is to improve the main results of this paper.

Small Intestinal Transit Does Not Adequately Represent Postoperative Paralytic Ileus in Rats

  • Lee, Hyun-Tai;Chung, Suk-Jae;Shim, Chang-Koo
    • Archives of Pharmacal Research
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    • v.25 no.6
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    • pp.978-983
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    • 2002
  • Small intestinal transit (SIT) has often been regarded as an index of pathophysiological state of postoperative ileus (PI) in rats. The reliability of SIT as an index of PI was examined in the present study. PI was induced via abdominal surgery (i.e., laparotomy with evisceration and manipulation) in rats. For one group of PI-induced rats, SIT of a charcoal test meal was measured. When necessary, the physical state (i.e., severity and site of distension) of the gastrointestinal (GI) tract in each rat was visually examined. For another group of PI-induced rats, abdominal X-ray radiographs were obtained after introducing the barium sulfate suspension. The abdomen was then opened and the physical state of the GI tract was visually examined. The SIT was decreased in most of the PI-induced rats, and the GI distension was observed, with substantial intersubject variations, in all of the PI-induced rats. However, no linear relationship was evident between the SIT and the severity of GI distension (e.g., at 20 h after PI induction). Instead, the severity and site of GI distension could be monitored by the X-ray radiology. Therefore, the use of SIT as an index of PI should be substantially limited.

A study on the growth diagnosis system for tomato (토마토 생육 진단 시스템 개발에 관한 연구)

  • Lee, ChangYeol
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.12
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    • pp.8673-8678
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    • 2015
  • This study is on the development of the growth diagnosis system for tomato. We defined the key index which affect to the growth of the tomato. Using the key index, we can make a diagnosis the status of the growth and take action to tomato. The index consists of Measure Index(MI) which is used to confirm the status of the tomato using the continuous growth check and Period Index(PI) which decide to the step whether vegetation period or reproductive growth period of the tomato. The system supports MI and PI recording module using the observation diary. In case of MI, the diagnosis is the result of the comparing work with the observed data and the standard value of MI. A a result of diagnosis, the system provides the action information. The system implemented to extend to the other plants. Using the system, Farms may be expected to enhance the productivity.

The Development of Leaves in Amaranthus retroflexus and Chenopodium album Represented by the Plastochron(I. The Derivation of the Plastochron Index) (Plastochron 에 의한 Amaranthus retroflexus 와 Chenopodium album 의 잎의 성장 해석 1. Plastochron Index 의 유도)

  • Park, Bong-Kyu;Joung-Hee Kim
    • The Korean Journal of Ecology
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    • v.8 no.1
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    • pp.1-5
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    • 1985
  • The plastochron index (PI) provides possibility on studies of the effects of various environmental factors on morphological and physiological development of plants. The PI of Erickson and Michemlini(1957) could be used merely when leaf n is longer an leaf n+1 is smaller than the references length at any time. If both the lengths of leaf n and n+1 are smaller or longer than the reference length, it could not estimated. In this study, the PI of Erickson and Michelini was complemented and the linear patterns according to leaf arrangement was represented, PI is n-(lnLR-lnLn)/(lnLn-lnLn+1). And when both the lengths of leaf n and n+1 are longer than the length of reference, PI is n+1+(ln Ln+1-lnLR)/(lnLn-lnLn+1). The linear model of PI is changed by the various environmental factors and the linear patterns are different according to leaf arrangement. According to leaf arrangement, the equation of the general regression lines is Yin-(i-j)=a-(n-1)(q1+...+qi-1)-(q1+...+qj-1)+rt+$\varepsilon$. Where Y:the logarithmic of the leaf length in question, i:leaf number hang on the one node, n:the number counting from base, q:spacing on the Y-axis, j:0, 1, 2, ..., r:slope, t:time, $\varepsilon$:error.

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