Papers

  1. Compact difference of Fejer-Riesz composition operators (with H. Koo and W. Smith), preprint
  2. The reproducing kernel thesis for difference of Hardy-space composition operators over the ball ( with K. Choi, H. Koo and I. Park), preprint
  3. Hilbert-Schmidt double differences of composition operators and non-rigid phenomenon (with X.Guo, T. Hosokawa, H. Koo, S. Ohno and M. Wang), J. Math. Anal. Appl. 543(March 2025), Article 128843(40p)
  4. Difference of weighted composition operators over the ball (with K. Choi, H. Koo and I. Park), Complex Analysis and Operator Theory, 18(Feb 2024), Article 33(33p)
  5. Compact difference of composition operators on the Hardy spaces (with K. Choi, H. Koo and I. Park), Trans. Amer. Math. Soc. Series B 9 (2022), 733-756
  6. Linear connection between composition operators on the Hardy space (with K. Choi, H. Koo and I. Park), J. Math. Anal. Appl. 515(1) (Nov 2022), Article 126402(39p)
  7. Invariant mean value property and M-harmonicity on the half-space (with K. Nam), Bull. Korean Math. Soc. 58(3) (May 2021), 559-572
  8. Difference of weighted composition operators II (with K. Choi, H. Koo and J. Yang), Integral Equations Operator Theory 93(2) (Apr 2021), Article: 17(19p)
  9. Path components of composition operators over the half-plane (with H. Koo, W. Smith and P. T. Tien), J. Math. Anal. Appl. 497(2) (May 2021), Article: 124861(35p)
  10. Difference of weighted composition operators (with K. Choi, H. Koo and J. Yang), J. Functional Analysis 278(5) (Mar 2020), Article: 108401(38p)
  11. Compact linear combination of composition operators on Bergman spaces (with H. Koo and W. Maofa), J. Functional Analysis 278(5) (Mar 2020), Article:108393(36p)
  12. New characterizations for the weighted Fock spaces (with K. Nam), Complex Analysis and Operator Theory 13(6) (Sep 2019), 2671-2686
  13.  Compact double differences of composition operators on the Bergman spaces over the ball(with H. Koo and J. Yang), Tohoku Math. J. 71(4) (Dec 2019), 609-637
  14. Linear fractional composition operators over the half-plane (with H. Koo and W. Smith), Integral Equations Operator Theory 90(3) (Jun 2018), Article:27(32p)
  15.  Sarason’s composition operator over the half-plane (with H. Koo and W. Smith), J. Math. Anal. Appl. 462 (Jun 2018)(2), 1309-1341
  16. Difference of composition operators over the half-plane (with H. Koo and W. Smith), Trans. Amer. Math. Soc. 369(5) (May 2017), 3173-3205
  17. Compact double differences of composition operators on the Bergman spaces (with H. Koo and M. Wang), J. Functional Analysis 272(Mar 2017), 2273-2307
  18. Compact linear combinations of composition operators induced by linear fractional maps (with H. Koo, M. Wang and J. Yang), Math. Z. 280(3) (Aug 2015), 807-824
  19. Fock-Sobolev spaces of fractional order (with H. Cho and H. Koo), Potential Analysis 43(2)(Aug 2015), 199-240
  20.  Commuting Toeplitz operators with pluriharmonic symbols on the Fock space, (with W. Bauer and H. Koo), J. Functional Analysis 268(10) (May 2015), 3017-3060
  21. Composition as an integral operator (with H. Koo and W. Smith), Advances in Math. 273(Mar 2015), 149-187
  22. Linear combinations of composition operators on the Fock-Sobolev spaces (with H. Cho and H. Koo), Potential Analysis 41(Nov 2014), 1223-1246
  23. Commutants of Toeplitz operators with radial symbols on the Fock-Sobole space (with J. Yang), J. Math. Anal. Appl. 415(Jul 2014), 779-790
  24.  Compact differences of composition operators on the Bergman spaces over the ball (with H. Koo and I. Park), Potential Analysis 40(Jan 2014), 81-102
  25. Weak Hopf lemma for the invariant Laplacian and related elliptic operators (with S. Cho and H. Koo), J. Math. Anal. Appl. 408(Dec 2013), 576-588
  26. Hardy Carleson measures and their dual Poisson-Szego transforms (with K. Izuchi and H. Koo), Potential Analysis 38(Jan 2013), 143-168
  27. Compact differences of composition operators over polydisks (with H. Koo and I. Park), Integral Equations Operator Theory 73(1) (May 2012), 57-91
  28.  Hilbert Schmidt differences of composition operators on the Bergman space (with T. Hosokawa and H. Koo), Math. Z. 269(Dec 2011), 751-775
  29. A note on composition operators acting on holomorphic Sobolev spaces (with H. Koo and W. Smith), Proc. Amer. Math. Soc. 139(Dec 2011), 4369-4375
  30.  Toeplitz products with pluriharmonic symbols on the Hardy space over the ball (with H. Koo and Y. J. Lee), J. Math. Anal. Appl. 381(Sep 2011), 365-382
  31.  Double integral characterizations of harmonic Bergman spaces (with K. Nam), J. Math. Anal. Appl. 379(Jul 2011) 889-909
  32. Finite rank products of Toeplitz operators on the harmonic Bergman space (with H. Koo and K. Na), Rocky Mountain J. Math.41(1)(Jan 2011), 45-78
  33. Positive Schatten-Herz class Toeplitz operators on the ball (with H. Koo and Y. J. Lee), New York J. Math. 17a (Jan 2011), 113-125
  34. Linear sums of two composition operators on the Fock space (with Kohei Izuchi and H. Koo), J. Math. Anal. Appl. 369(1)(Sep 2010), 112-119
  35. Optimal norm estimate of operators related to the harmonic Bergman projection on the ball (with H. Koo and K. Nam), Tohoku Math. J. 62(Sep. 2010), 357-374
  36. Carleson measures for Bergman spaces and their dual Berezin transforms (with H. Koo and M. Stessin), Proc. Amer. Math. Soc. 137(12)(Dec 2009), 4143-4155
  37. Berezin transform and Toeplitz operators on harmonic Bergman spaces (with K. Nam), J. Functional Analysis 257(10)(Nov 2009), 3135-3166
  38. Finite sums of Toeplitz products on the polydisk (with H. Koo and Y. J. Lee), Potential Analysis 31(3)(Oct 2009), 227-255
  39. Finite rank product theorems for Toeplitz operators on the half-space (with H. Koo and K. Nam), J. Math. Soc. Japan 61(3)(Jul 2009), 885-919
  40. Carleson measures via BMO (with H. Koo and M. Stessin), Integral Equations Operator Theory 63(4)(Apr 2009), 501-520
  41. On higher dimensional Luecking’s theorem, J. Math. Soc. Japan 61(1)(Jan 2009), 213-224
  42. Positive Schatten class Toeplitz operators on the ball (with H. Koo and Y. J. Lee), Studia Math. 189(1)(Nov 2008), 65-90
  43. Finite rank Toeplitz products with harmonic symbols (with H. Koo and Y. J. Lee), J. Math. Anal. Appl. 343(Jul 2008), 81-98
  44. Sums of Toeplitz products with harmonic symbols (with H. Koo and Y. J. Lee), Revista Mat. Iberoamericana 24(1)(Apr 2008), 43-70
  45. Carleson measures for the area Nevanlinna spaces and applications (with H. Koo and W. Smith), J. Anal. Math.104(1) (Jan 2008), 207-233
  46. Note on atomic decompositions of harmonic Bergman functions (with Y. J. Lee), Proceedings of the 15th ICFIDCAA; Complex Analysis and its Applications, Osaka Municipal Universities Press, OCAMI Studies Series 2(2007), 11-24.
  47. Toeplitz operators and Herz spaces on the half-space (with K. S. Nam), Integral Equations Operator Theory 59(4)(Dec 2007), 501-521
  48. Positive Schatten(-Herz) class Toeplitz operators on the half-space (with H. Koo and Y. J. Lee), Potential Analysis 27(1)(Aug 2007), 73-100
  49. Positive Toeplitz operators of Schatten-Herz type (with H. Koo and K. Na), Nagoya Math. J. 185(2007), 31-62
  50. Zero products of Toeplitz operators with n-harmonic symbols (with H. Koo and Y. J. Lee), Integral Equations Operator Theory 57(2007), 43-66
  51.  Products of Bergman space Toeplitz operators on the polydisk (with Y. J. Lee, K. Nam and D. Zheng), Math. Ann. 337(2007), 295-316
  52.  Note on the Berezin transform on Herz spaces, RIMS Kyokuroku 1519(2006), 21-37
  53. Composition operators on small spaces (with H. Koo and W. Smith), Integral Equations Operator Theory 56(3)(2006), 357-380
  54. Note on commuting Toeplitz operators on the pluriharmonic Bergman space (with K. S. Nam), J. Korean Math. Soc. 43(2006), No. 2, 259-269
  55. Zero products of Toeplitz operators with harmonic symbols (with H. Koo), J. Functional Analysis 233(2006), No. 2, 307-334
  56. Commutants of analytic Toeplitz operators on the harmonic Bergman space (with Y. J. Lee), Integral Equations Operator Theory 50(2004), 559-564
  57. Projections for harmonic Bergman spaces and applications (with H. Koo and H. Yi), J. Functional Analysis 216(2) (2004), 388-421
  58. Toeplitz operators on harmonic Bergman spaces (with Y. J. Lee and K. Na), Nagoya Math. J. 174(2004), 165-186
  59. Positive Toeplitz operators from a harmonic Bergman space into another (with Y. J. Lee and K. Na), Tohoku Math. J. 56(2004), 255-270
  60.  Commuting Toeplitz operators on the polydisk (with H. Koo and Y. J. Lee), Trans. Amer. Math. Soc. 356(2004), 1727-1749
  61.  Moment vanishing properties of harmonic Bergman functions (with H. Koo and H. Yi), J. Math. Anal. Appl. 296(2)(2003), 365-381
  62. Composition operators acting on holomorphic Sobolev spaces (with H. Koo and W. Smith), Trans. Amer. Math. Soc. 355(2003), 2829-2855
  63.  Harmonic Bergman Functions as Radial Derivatives of Bergman Functions (with H. Koo and H. Yi), Proc. Amer. Math. Soc. 131(2003), 401-408
  64. Carleson type conditions and weghted inequalities for harmonic functions (with H. Koo and H. Yi), Osaka J. Math. 39(2002), 945-962
  65. Positive Toeplitz operators between the harmonic Bergman spaces (with H. Koo and H. Yi), Potential Analysis 17(2002), 307-335
  66. Derivatives of harmonic Bergman and Bloch functions on the ball (with H. Koo and H. Yi), J. Math. Anal. Appl. 260(2001), 100-123
  67. The numerical range and normality of Toeplitz operators (with Y. J. Lee), Far East J. Math., Special Volume(2001), Part I, 71-80
  68. Bergman norm estimates of Poisson integrals (with H. Koo and H. Yi), Nagoya Math. J. 161(2001), 85-125
  69. Gleason’s problem for harmonic Bergman and Bloch functions on half-spaces (with H. Koo and H. Yi), Integral Equations Operator Theory 36(2000), 269-287
  70. Images of Hankel operators on the polydisk (with Y. J. Lee), Bull. Australian Math. Soc. 59(1999), 403-408
  71. Commuting Toeplitz operators on the harmonic Bergman space (with Y. J. Lee), Michigan Math. J. 46(1999) 163-174
  72. Representation and interpolation theorems of harmonic Bergman functions on half-spaces (with H. Yi), Nagoya Math. J. 151(1998), 51-89
  73.  Pluriharmonic symbols of essentially commuting Toeplitz operators (with Y. J. Lee), Illinois J. Math. 42(1998), 280-293
  74. On $\mathcal M$-harmonic functions and their Carleson measures (with Y. J. Lee), Glasgow Math. J. 40(1998), 273-289
  75.  Bloch-to-BMOA pullbacks on the disk (with W. Ramey & D. Ullrich), Proc. Amer. Math. Soc. 125(1997), 2987-2996
  76. The essential spectra of Toeplitz operators with symbols in H^\infty +C (with Y. J. Lee), Math. Japonica 45(1)(1997), 1-4
  77. Fractional derivatives of Bloch functions, growth rate, and interpolation (with K. S. Rim), Acta Math. Hungarica 72(1-2)(1996), 67-86
  78. Norm and essential norm estimates of Toeplitz operators on the Bergman space (with Y. J. Lee), Comm. Korean Math. Soc. 11(1996), No.4, 937-958
  79. A Luecking type subspace, dualities and Toeplitz operators (with Y. J. Lee), Acta Math. Hungarica 67(1995), 151-170
  80. Compact Toeplitz operators with bounded symbols on the Bergman spaces (with Y. J. Lee), J. Korean Math. Soc. 3(1994), 289-307
  81. Pluriharmonic symbols of commuting Toeplitz operators (with Y. J. Lee), Illinois J. Math. 37(1993), 424-436
  82. Bocher’s theorem for M-harmonic functions, Houston J. Math. 18(1993), 539-549
  83. On the boundary behavior of functions holomorphic on the ball (with H. O. Kim), Complex Variables 20(1992), 53-62
  84. The essential norms of composition operators, Glasgow Math. J. 34(1992), 143-155
  85. A Functional equation of Pexider type, Funcialaj Ekvacioj 35 (1992), 255-259
  86. Composition with a homogeneous polynomial (with J. S. Choa), Bull. Korean Math. Soc. 29(1992), 57-63
  87. A Littlewood-Paley type identity and a characterization of BMOA (with J. S. Choa), Complex Variables 17(1991), 15-23
  88. Derivatives of Hardy functions, Proc. Amer. Math. Soc. 110(1990), 781-788
  89. Projections, the weighted Bergman spaces, and the Bloch space, Proc. Amer. Math. Soc. 108(1990 ), 127-136
  90. An integral mean inequality for Hadamard products on the polydisc, Complex Variables 13(1990), 213-215
  91. Cauchy integral equalities and applications, Trans. Amer. Math. Soc. 315(1989), 337-352
  92.  Composition property of holomorphic functions on the ball, Michigan Math. J. 36(1989), 289-301
  93. Weights induced by homogneous polynomials, Pacific J. Math. 139(1989), 225-240
  94. Composition with bounded holomorphic functions, PhD Thesis (supervised by W. Rudin), University of Wisconsin, Madison, 1988.
  95. An elementary proof of $\sum n^{-2}=\pi^2 /6$, Amer. Math. Monthly 94(1987), 662-663