Papers

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