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Volumn 32, Issue 5, 1996, Pages 503-519

General mathematical model for forest fires and its applications

Author keywords

[No Author keywords available]

Indexed keywords


EID: 0030335747     PISSN: 00105082     EISSN: None     Source Type: Journal    
DOI: 10.1007/BF01998573     Document Type: Article
Times cited : (10)

References (73)
  • 1
    • 0004345869 scopus 로고
    • Mathematical modeling of forest fires
    • Inst. of Theor. and Appl. Mech., Sib. Div., Acad. of Sci. of the USSR
    • A. M. Grishin, "Mathematical modeling of forest fires," in: Numerical Methods of Continuum Mechanics [in Russian], Inst. of Theor. and Appl. Mech., Sib. Div., Acad. of Sci. of the USSR (1978), pp. 30-56.
    • (1978) Numerical Methods of Continuum Mechanics [in Russian] , pp. 30-56
    • Grishin, A.M.1
  • 8
    • 0039176861 scopus 로고
    • Experimental investigation of structure of the crown forest fire front
    • A. M. Grishin and V. V. Plyukhin, "Experimental investigation of structure of the crown forest fire front," Fiz. Goreniya Vzryva, 21, No. 1, 21-26 (1985).
    • (1985) Fiz. Goreniya Vzryva , vol.21 , Issue.1 , pp. 21-26
    • Grishin, A.M.1    Plyukhin, V.V.2
  • 10
    • 0029171164 scopus 로고
    • A method of experimental determination of parameters in the forest zone
    • A. M. Grishin, A. N. Golovanov, and V. G. Smirnov, "A method of experimental determination of parameters in the forest zone," Fiz. Goreniya Vzryva, 31, No. 3, 3-9 (1995).
    • (1995) Fiz. Goreniya Vzryva , vol.31 , Issue.3 , pp. 3-9
    • Grishin, A.M.1    Golovanov, A.N.2    Smirnov, V.G.3
  • 21
    • 0020721125 scopus 로고
    • Mathematical modelling of natural convection in fire. A state of the art review of the field modelling of variable density turbulent flow
    • S. Kumar, "Mathematical modelling of natural convection in fire. A state of the art review of the field modelling of variable density turbulent flow," Fire Mater., 7, No. 1, 1-24 (1983).
    • (1983) Fire Mater. , vol.7 , Issue.1 , pp. 1-24
    • Kumar, S.1
  • 28
    • 0039769347 scopus 로고
    • On numerical simulation of some problems of mathematical theory of forest fires
    • Nauka, Novosibirsk
    • V. A. Perminov and O. V. Shipulina, "On numerical simulation of some problems of mathematical theory of forest fires," in: Physical Gas Dynamics of Reacting Media [in Russian], Nauka, Novosibirsk (1990), pp. 158-169.
    • (1990) Physical Gas Dynamics of Reacting Media [in Russian] , pp. 158-169
    • Perminov, V.A.1    Shipulina, O.V.2
  • 33
    • 0040955643 scopus 로고
    • Aerodynamics and heat and mass exchange between the front of a forest fire and the surface layer of the atmosphere
    • A. M. Grishin, A. D. Gruzin, and É. É. Gruzina, "Aerodynamics and heat and mass exchange between the front of a forest fire and the surface layer of the atmosphere," Prikl. Mekh. Tekh. Fiz., No. 6, 91-96 (1984).
    • (1984) Prikl. Mekh. Tekh. Fiz. , Issue.6 , pp. 91-96
    • Grishin, A.M.1    Gruzin, A.D.2    Gruzina, E.E.3
  • 34
    • 0039176829 scopus 로고
    • Convective heat and mass transfer and spread of burning particles in the near-ground atmospheric layer in crown fires
    • A. M. Grishin and A. D. Gruzin, "Convective heat and mass transfer and spread of burning particles in the near-ground atmospheric layer in crown fires," Dokl. Akad. Nauk SSSR, 253, No. 3, 549-553 (1980).
    • (1980) Dokl. Akad. Nauk SSSR , vol.253 , Issue.3 , pp. 549-553
    • Grishin, A.M.1    Gruzin, A.D.2
  • 35
    • 0039769273 scopus 로고
    • Mathematical modeling of the spread of crown fires
    • A. M. Grishin, V. G. Zverev, and A. D. Gruzin, "Mathematical modeling of the spread of crown fires," Dokl. Akad. Nauk SSSR, 269, No. 4, 822-826 (1983).
    • (1983) Dokl. Akad. Nauk SSSR , vol.269 , Issue.4 , pp. 822-826
    • Grishin, A.M.1    Zverev, V.G.2    Gruzin, A.D.3
  • 37
    • 0039176772 scopus 로고
    • Heat and mass transport and the propagation of burning particles in the surface layer of the atmosphere during upstream forest fires
    • A. M. Grishin, A. D. Gruzin, and V. G. Zverev "Heat and mass transport and the propagation of burning particles in the surface layer of the atmosphere during upstream forest fires," Fiz. Goreniya Vzryva, 17, No. 4, 78-84 (1981).
    • (1981) Fiz. Goreniya Vzryva , vol.17 , Issue.4 , pp. 78-84
    • Grishin, A.M.1    Gruzin, A.D.2    Zverev, V.G.3
  • 39
    • 0021516856 scopus 로고
    • Propagation of thermic developing fire in the near-earth atmospheric layer
    • A. M. Grishin, N. A. Alekseev, O. P. Brabander, and V. F. Zalmezh, "Propagation of thermic developing fire in the near-earth atmospheric layer," Scr. Tech. USA, 16, 28-38 (1984).
    • (1984) Scr. Tech. USA , vol.16 , pp. 28-38
    • Grishin, A.M.1    Alekseev, N.A.2    Brabander, O.P.3    Zalmezh, V.F.4
  • 40
    • 0022147194 scopus 로고
    • Mathematical theory of crown forest fire
    • A. M. Grishin, V. G. Zverev, and A. D. Gruzin, "Mathematical theory of crown forest fire," Scr. Tech. USA, 17, No. 6, 41-49 (1986).
    • (1986) Scr. Tech. USA , vol.17 , Issue.6 , pp. 41-49
    • Grishin, A.M.1    Zverev, V.G.2    Gruzin, A.D.3
  • 41
    • 0039769348 scopus 로고
    • Two-dimensional instability of an upper forest fire front
    • A. M. Grishin, E. E. Zelenskii, and S. V. Shevelev, "Two-dimensional instability of an upper forest fire front," Fiz. Goreniya Vzryva, 26, No. 3, 7-17 (1990).
    • (1990) Fiz. Goreniya Vzryva , vol.26 , Issue.3 , pp. 7-17
    • Grishin, A.M.1    Zelenskii, E.E.2    Shevelev, S.V.3
  • 42
    • 0040361390 scopus 로고
    • Study of the structure and limits of propagation of the front of an upstream forest fire
    • A. M. Grishin, A. D. Gruzin, and V. G. Zverev "Study of the structure and limits of propagation of the front of an upstream forest fire," Fiz. Goreniya Vzryva, 21, No. 1, 11-21 (1985).
    • (1985) Fiz. Goreniya Vzryva , vol.21 , Issue.1 , pp. 11-21
    • Grishin, A.M.1    Gruzin, A.D.2    Zverev, V.G.3
  • 44
    • 0040365611 scopus 로고
    • Stability of propagation of a crown fire front at a finite rate of interphase heat exchange
    • Nauka, Novosibirsk
    • A. M. Grishin and E. E. Zelenskii, "Stability of propagation of a crown fire front at a finite rate of interphase heat exchange," in: Physical Gas Dynamics of Reacting Media [in Russian], Nauka, Novosibirsk (1990), pp. 47-60.
    • (1990) Physical Gas Dynamics of Reacting Media [in Russian] , pp. 47-60
    • Grishin, A.M.1    Zelenskii, E.E.2
  • 45
    • 0039769362 scopus 로고
    • Steady propagation of a crown fire front
    • A. M. Grishin, "Steady propagation of a crown fire front," Dokl. Akad. Nauk SSSR, 279, No. 3, 550-554 (1984).
    • (1984) Dokl. Akad. Nauk SSSR , vol.279 , Issue.3 , pp. 550-554
    • Grishin, A.M.1
  • 46
    • 0004186114 scopus 로고
    • Steady-state propagation of top crown forest fires
    • A. M. Grishin, V. G. Zverev, and S. V. Shevelev, "Steady-state propagation of top crown forest fires," Fiz. Goreniya Vzryva, 22, No. 6, 101-108 (1986).
    • (1986) Fiz. Goreniya Vzryva , vol.22 , Issue.6 , pp. 101-108
    • Grishin, A.M.1    Zverev, V.G.2    Shevelev, S.V.3
  • 47
    • 0039769350 scopus 로고
    • Ignition of the forest canopy in the case of top-growth fires and calculation of the width of firebreaks
    • A. M. Grishin and V. G. Zverev, "Ignition of the forest canopy in the case of top-growth fires and calculation of the width of firebreaks,$ Fiz. Goreniya Vzryva, 18, No. 4, 3-11 (1982).
    • (1982) Fiz. Goreniya Vzryva , vol.18 , Issue.4 , pp. 3-11
    • Grishin, A.M.1    Zverev, V.G.2
  • 48
    • 70449587470 scopus 로고
    • Transition of forest ground fire to crown fire
    • A. M. Grishin and V. A. Perminov, $Transition of forest ground fire to crown fire,$ Fiz. Goreniya Vzryva, 26, No. 6, 3-10 (1990).
    • (1990) Fiz. Goreniya Vzryva , vol.26 , Issue.6 , pp. 3-10
    • Grishin, A.M.1    Perminov, V.A.2
  • 49
    • 0030089339 scopus 로고    scopus 로고
    • Ignition of forest tracts as a result of cosmic or technogenic catastrophes
    • A. M. Grishin, K. N. Efimov, and V. A. Perminov, $Ignition of forest tracts as a result of cosmic or technogenic catastrophes,$ Fiz. Goreniya Vzryva, 32, No. 2, 18-30 (1996).
    • (1996) Fiz. Goreniya Vzryva , vol.32 , Issue.2 , pp. 18-30
    • Grishin, A.M.1    Efimov, K.N.2    Perminov, V.A.3
  • 50
    • 0030223746 scopus 로고    scopus 로고
    • Ignition of forest tracts by a high-altitude source of radiant energy
    • A. M. Grishin and V. A. Perminov, $Ignition of forest tracts by a high-altitude source of radiant energy,$ Fiz. Goreniya Vzryva, 32, No. 5, 107-115 (1996).
    • (1996) Fiz. Goreniya Vzryva , vol.32 , Issue.5 , pp. 107-115
    • Grishin, A.M.1    Perminov, V.A.2
  • 51
    • 0040361461 scopus 로고
    • Investigation of the interaction of blast waves with vegetation and forest fire front
    • Nauka, Novosibirsk
    • A. M. Grishin and Yu. M. Kovalev, $Investigation of the interaction of blast waves with vegetation and forest fire front,$ in: Physical Gas Dynamics of Reacting Media [in Russian], Nauka, Novosibirsk (1990), pp. 60-68.
    • (1990) Physical Gas Dynamics of Reacting Media [in Russian] , pp. 60-68
    • Grishin, A.M.1    Kovalev, Yu.M.2
  • 52
    • 0040361453 scopus 로고
    • On amplification of blast waves under interaction with forest fire front
    • A. M. Grishin and Yu. M. Kovalev, $On amplification of blast waves under interaction with forest fire front,$ Dokl. Akad. Nauk SSSR, 313, No. 1, 50-54 (1990).
    • (1990) Dokl. Akad. Nauk SSSR , vol.313 , Issue.1 , pp. 50-54
    • Grishin, A.M.1    Kovalev, Yu.M.2
  • 53
    • 0039162969 scopus 로고
    • Experimental and theoretical investigation of the effect of an explosion on the front of crown forest fires
    • A. M. Grishin and Yu. M. Kovalev, $Experimental and theoretical investigation of the effect of an explosion on the front of crown forest fires,$ Fiz. Goreniya Vzryva, 25, No. 6, 72-79 (1989).
    • (1989) Fiz. Goreniya Vzryva , vol.25 , Issue.6 , pp. 72-79
    • Grishin, A.M.1    Kovalev, Yu.M.2
  • 54
    • 0040955627 scopus 로고
    • Experimental investigation of the effect of an explosion of condensed explosives on the crown fire front
    • A. M. Grishin and Yu. M. Kovalev, $Experimental investigation of the effect of an explosion of condensed explosives on the crown fire front,$ Dokl. Akad. Nauk SSSR, 308, No. 5, 77-78 (1989).
    • (1989) Dokl. Akad. Nauk SSSR , vol.308 , Issue.5 , pp. 77-78
    • Grishin, A.M.1    Kovalev, Yu.M.2
  • 55
    • 0039769342 scopus 로고
    • Effect of the forest crown fire front on glass-reinforced plastic
    • A. M. Grishin and S. P. Sinitsyn, "Effect of the forest crown fire front on glass-reinforced plastic," Fiz. Goreniya Vzryva, 26, No. 6, 35-42 (1990).
    • (1990) Fiz. Goreniya Vzryva , vol.26 , Issue.6 , pp. 35-42
    • Grishin, A.M.1    Sinitsyn, S.P.2
  • 56
    • 0040361462 scopus 로고
    • Analysis of the spread of forest fires and burns
    • Inst. Therm. Phys., Sib. Div., Acad. of Sci. of the USSR
    • É. V. Konev, "Analysis of the spread of forest fires and burns," in: Thermal Physics of Forest Fires [in Russian], Inst. Therm. Phys., Sib. Div., Acad. of Sci. of the USSR (1984), pp. 99-125.
    • (1984) Thermal Physics of Forest Fires [in Russian] , pp. 99-125
    • Konev, É.V.1
  • 57
    • 0039176849 scopus 로고
    • Modeling fire spread through fuel beds
    • R. O. Veber, "Modeling fire spread through fuel beds," Prog. Energ. Combust. Sci., 17, 65-82 (1990).
    • (1990) Prog. Energ. Combust. Sci. , vol.17 , pp. 65-82
    • Veber, R.O.1
  • 59
    • 0040361454 scopus 로고    scopus 로고
    • Method for confining forest fire spread
    • Inventor's Certificate No. 1134202 SSSR, MKI A 62 S 3/02, No. 3515538. Applied for on 10.25.82. Published 01.10.85
    • Inventor's Certificate No. 1134202 SSSR, MKI A 62 S 3/02, "Method for confining forest fire spread (A. M. Grishin, V. M. Babaev, V. E. Abaltusov, A. D. Gruzin, V. G. Zverev, and V. V. Plukhin)," No. 3515538. Applied for on 10.25.82. Published 01.10.85. Byul. No. 2.
    • Byul. , Issue.2
    • Grishin, A.M.1    Babaev, V.M.2    Abaltusov, V.E.3    Gruzin, A.D.4    Zverev, V.G.5    Plukhin, V.V.6
  • 60
    • 0039769363 scopus 로고    scopus 로고
    • Method for forest-fire localization and extinguishing
    • Inventor's Certificate No. 1405848 SSSR, MKI A 62 S 1/22, No 4171019. Applied for on 10.19.86. Published 06.30.88
    • Inventor's Certificate No. 1405848 SSSR, MKI A 62 S 1/22, "Method for forest-fire localization and extinguishing (A. M. Grishin, A. N. Golovanov, I. P. Baidin, and A. S. Chekerenda)," No 4171019. Applied for on 10.19.86. Published 06.30.88. Byul. No. 24.
    • Byul. , Issue.24
    • Grishin, A.M.1    Golovanov, A.N.2    Baidin, I.P.3    Chekerenda, A.S.4
  • 61
    • 0040955635 scopus 로고    scopus 로고
    • Method for localization of forest fires
    • Inventor's Certificate No. 1147413 SSSR, MKI A 62 S 1/00, No. 3359093. Applied for on 12.01.81. Published 03.30.85
    • Inventor's Certificate No. 1147413 SSSR, MKI A 62 S 1/00, "Method for localization of forest fires (A. M. Grishin, V. M. Babaev, V. E. Abaltusov, A. D. Gruzin, and V. G. Zverev)," No. 3359093. Applied for on 12.01.81. Published 03.30.85. Byul. No. 12.
    • Byul. , Issue.12
    • Grishin, A.M.1    Babaev, V.M.2    Abaltusov, V.E.3    Gruzin, A.D.4    Zverev, V.G.5
  • 62
    • 0040955647 scopus 로고    scopus 로고
    • Method of forest-fire extinguishing
    • Inventor's Certificate No. 1644976 A 1 SSSR, MKI A 62 S 3/02, No. 4644603. Applied for on 06.02.88. Published 04.30.91
    • Inventor's Certificate No. 1644976 A 1 SSSR, MKI A 62 S 3/02, "Method of forest-fire extinguishing," No. 4644603. Applied for on 06.02.88. Published 04.30.91. Byul. No. 16.
    • Byul. , Issue.16
  • 63
    • 0039769356 scopus 로고    scopus 로고
    • Method for forest-fire localization
    • Inventor's Certificate No. 1556687 A 1 SSSR, MKI A 62 S 3/02, No. 4358906. Applied for on 01.05.88. Published 04.15.90
    • Inventor's Certificate No. 1556687 A 1 SSSR, MKI A 62 S 3/02, "Method for forest-fire localization (A. M. Grishin, A. N. Golovanov, V. I. Ziatinin, A. N. Spirin, R. V. Isakov, and G. S. Loskutov)," No. 4358906. Applied for on 01.05.88. Published 04.15.90. Byul. No. 14.
    • Byul. , Issue.14
    • Grishin, A.M.1    Golovanov, A.N.2    Ziatinin, V.I.3    Spirin, A.N.4    Isakov, R.V.5    Loskutov, G.S.6
  • 64
    • 0040361450 scopus 로고    scopus 로고
    • Method for forest-fire extinguishing
    • Inventor's Certificate No. 1657199 A 1 SSSR, MKI A 62 S 3/02, No. 4661231/31. Applied for on 01.03.89. Published 06.23.91
    • Inventor's Certificate No. 1657199 A 1 SSSR, MKI A 62 S 3/02, "Method for forest-fire extinguishing," No. 4661231/31. Applied for on 01.03.89. Published 06.23.91. Byul. No. 23.
    • Byul. , Issue.23
  • 65
    • 0040361457 scopus 로고    scopus 로고
    • Method for forest-fire extinguishing
    • Inventor's Certificate No. 1400619 A 1 SSSR, MKI A 62 S 1/22, No. 4160481/31. Applied for on 12.08.86. Published 06.07.88
    • Inventor's Certificate No. 1400619 A 1 SSSR, MKI A 62 S 1/22, "Method for forest-fire extinguishing (A. M. Grishin, N. A. Alekseev, and N. A. Andreev)," No. 4160481/31. Applied for on 12.08.86. Published 06.07.88. Byul. No. 21.
    • Byul. , Issue.21
    • Grishin, A.M.1    Alekseev, N.A.2    Andreev, N.A.3
  • 66
    • 0040361457 scopus 로고    scopus 로고
    • Device for forest-fire extinguishing
    • Inventor's Certificate No. 1657198 A 1 SSSR, MKI A 62 S 3/02, No. 4661158. Applied for on 01.03.88. Published 06.23.91
    • Inventor's Certificate No. 1657198 A 1 SSSR, MKI A 62 S 3/02, "Device for forest-fire extinguishing (A. M. Grishin, A. N. Golovanov, N. A. Andreev, and P. N. Pryakhin)," No. 4661158. Applied for on 01.03.88. Published 06.23.91. Byul. No. 23.
    • Byul. , Issue.23
    • Grishin, A.M.1    Golovanov, A.N.2    Andreev, N.A.3    Pryakhin, P.N.4
  • 67
    • 0039769351 scopus 로고    scopus 로고
    • Method for preventing transition from surface fire to crown fire
    • Inventor's Certificate No. 1697855 SSSR, MKI A 62 S 3/02, No. 4771930. Applied for on 12.19.89. Published 12.15.91
    • Inventor's Certificate No. 1697855 SSSR, MKI A 62 S 3/02, "Method for preventing transition from surface fire to crown fire (A. M. Grishin, N. A. Alekseev, A. V. Orlov, and Yu. V. Kustov)," No. 4771930. Applied for on 12.19.89. Published 12.15.91. Byul. No. 46.
    • Byul. , Issue.46
    • Grishin, A.M.1    Alekseev, N.A.2    Orlov, A.V.3    Kustov, Yu.V.4
  • 68
    • 0040361457 scopus 로고    scopus 로고
    • Method for forest-fire extinguishing
    • Inventor's Certificate No. 1644976 SSSR, MKI A 62 S 3/02, No. 4644603. Applied for on 12.26.88. Published 04.30.92
    • Inventor's Certificate No. 1644976 SSSR, MKI A 62 S 3/02, "Method for forest-fire extinguishing (A. M. Grishin, N. A. Alekseev, and A. N. Golovanov)," No. 4644603. Applied for on 12.26.88. Published 04.30.92. Byul. No. 16.
    • Byul. , Issue.16
    • Grishin, A.M.1    Alekseev, N.A.2    Golovanov, A.N.3
  • 69
    • 0040361457 scopus 로고    scopus 로고
    • Method for forest-fire extinguishing
    • Inventor's Certificate No. 1657199 A 1 SSSR, MKI A 62 S 3/02, No. 4661231. Applied for on 01.03.89. Published 06.23.91
    • Inventor's Certificate No. 1657199 A 1 SSSR, MKI A 62 S 3/02, "Method for forest-fire extinguishing (A. M. Grishin, A. N. Golovanov, and B. I. Kulakov)," No. 4661231. Applied for on 01.03.89. Published 06.23.91. Byul. No. 23.
    • Byul. , Issue.23
    • Grishin, A.M.1    Golovanov, A.N.2    Kulakov, B.I.3
  • 70
    • 0039769363 scopus 로고    scopus 로고
    • Method for forest-fire localization and extinguishing
    • Inventor's Certificate No. 1400619 A 1 SSSR, MKI A 62 S 1/22, No. 4883879. Applied for on 10.08.90. Published 02.23.93
    • Inventor's Certificate No. 1400619 A 1 SSSR, MKI A 62 S 1/22, "Method for forest-fire localization and extinguishing (A. M. Grishin, V. A. Antonov, L. Yu. Naimushina, and A. N. Golovanov)," No. 4883879. Applied for on 10.08.90. Published 02.23.93. Byul. No. 7.
    • Byul. , Issue.7
    • Grishin, A.M.1    Antonov, V.A.2    Naimushina, L.Yu.3    Golovanov, A.N.4
  • 71
    • 0040361457 scopus 로고    scopus 로고
    • Method for forest-fire extinguishing
    • USSR Patent No. 1834667, A3 from 10.13.92, MKI A 62 S2/00, declaration No. 4938111 with priority from 05.23.1991. Published 08.15.93
    • A. M. Grishin, A. N. Golovanov, and V. F. Shleptsov, "Method for forest-fire extinguishing," USSR Patent No. 1834667, A3 from 10.13.92, MKI A 62 S2/00, declaration No. 4938111 with priority from 05.23.1991. Published 08.15.93. Byul. No. 30.
    • Byul. , Issue.30
    • Grishin, A.M.1    Golovanov, A.N.2    Shleptsov, V.F.3
  • 72
    • 0039769363 scopus 로고    scopus 로고
    • Method for forest-fire localization and extinguishing
    • Russian Federation Patent No. 1796204 A1 SSSR, MKI A 62 2/00, declaration No. 4883879 with priority from 10.08.90. Published 02.23.93
    • A. M. Grishin, V. A. Antonov, L. Yu. Naimushina, and A. N. Golovanov, "Method for forest-fire localization and extinguishing," Russian Federation Patent No. 1796204 A1 SSSR, MKI A 62 2/00, declaration No. 4883879 with priority from 10.08.90. Published 02.23.93. Byul. No. 7.
    • Byul. , Issue.7
    • Grishin, A.M.1    Antonov, V.A.2    Naimushina, L.Yu.3    Golovanov, A.N.4
  • 73
    • 0039176832 scopus 로고    scopus 로고
    • Device for forest-fire localization and extinguishing
    • Russian Federation Patent No. 2033826 S1 SSSR, MKI S 62 3/02, declaration with priority from 07.20.90. Published 04.30.95
    • A. M. Grsihin, V. A. Antonov, L. Yu. Naimushina, and A. N. Golovanov "Device for forest-fire localization and extinguishing," Russian Federation Patent No. 2033826 S1 SSSR, MKI S 62 3/02, declaration with priority from 07.20.90. Published 04.30.95. Byul. No. 12.
    • Byul. , Issue.12
    • Grsihin, A.M.1    Antonov, V.A.2    Naimushina, L.Yu.3    Golovanov, A.N.4


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.