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GREENWOOD / BLACK WALL STREET WILMINGTON 1898 LITTLE ROCK NINE TUSKEGEE STUDY ROSEWOOD 1923 THE TUSKEGEE AIRMEN SENECA VILLAGE BLACK TOWNS GREENWOOD / BLACK WALL STREET WILMINGTON 1898 LITTLE ROCK NINE TUSKEGEE STUDY ROSEWOOD 1923 THE TUSKEGEE AIRMEN SENECA VILLAGE BLACK TOWNS
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MY'STORY

The MOVE Fire

This is a personal recollection on the Move fire on May 13, 1985 Philadelphia police fired thousands of rounds at the MOVE house, city officials approved dropping an explosive device on the roof, the resulting fire was allowed to burn, 11 people—including five children—died, and 61 homes were destroyed. Philadelphia City Council later called it a “brutal attack carried out by the City of Philadelphia on its own citizens” and acknowledged that no individual faced criminal consequences for the bombing. One timeline correction worth preserving for the BHP record: the major previous MOVE-police confrontation was August 8, 1978, about seven years before the bombing, not a year or two earlier. Officer James Ramp was killed, other police and firefighters were wounded, nine MOVE members were later convicted, and television cameras recorded police beating Delbert Africa during his arrest. The 1985 MOVE Commission later specifically criticized city planners for failing to adequately use lessons from that 1978 confrontation. And that actually strengthens the point you’re making: 1985 did not happen without precedent or institutional memory. There had already been a deadly confrontation with MOVE, years of conflict, negotiations and police involvement before Osage Avenue.

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BLACK FACTS
The Truths They Never Taught You...

Ruler of the Mali Empire in the 14th century

Mansa Musa was the ruler of the Mali Empire in West Africa. Details recorded here should be sourced; unknown information is left blank.

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BHP gathered finds from its connected research sources. Showing the 4 strongest Black History matches.
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Wikipedia

Workshop on Numerical Ranges and Numerical Radii

Workshop on Numerical Ranges and Numerical Radii (WONRA) is a biennial workshop series on numerical ranges and numerical radii which began in 1992.

About

[edit]

Numerical ranges and numerical radii are useful in the study of matrix and operator theory. These topics have applications in many subjects in pure and applied mathematics, such as quadratic forms, Banach spaces, dilation theory, control theory, numerical analysis, quantum information science.[1] [2] [3] [4] [5] [6] [7]

History

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In the early 1970s, numerical range workshops were organized by Frank Bonsall and John Duncan. More activities were started in early 1990s, including the biennial workshop series, which began in 1992, and special issues devoted to this workshop were published.[8] [9] [10] [11]

Workshops

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# Year Location Organizer(s) Participation Workshop photo
1 1992 United States Williamsburg, VA, USA C. Johnson, C.K. Li 33 Photo
2 1994 Portugal Coimbra, Portugal, N. Bebiano 36 Photo
3 1996 Japan Sapporo, Hokkaido, Japan T. Ando and K. Okubo 36 Photo
4 1998 United States Madison, WI, USA R. Brualdi, C.K. Li 30 Photo
5 2000 Greece Nafplio, Greece J. Maroulas, M. Tsatsomeros 29 Photo
6 2002 United States Auburn, AL, USA C.K. Li, T.Y. Tam 30 Photo
7 2004 Portugal Coimbra, Portugal N. Bebiano, R. Lemos, G. Soares 40 Photo
8 2006 Germany Bremen, Germany C.K. Li, L. Rodman, C. Tretter 39 Photo
9 2008 United States Williamsburg, VA, USA C.K. Li 29 Photo
10 2010 Poland Krakow, Poland C.K. Li, F.H. Szafraniec, J. Zemanek 40 Photo
11 2012 Taiwan Kaohsiung, Taiwan C.K. Li, N.C. Wong 48 Photo
12 2014 China Sanya, China S.Y. Cheng, M.D. Choi, C.K. Li 43 Photo
13 2016 Taiwan Taipei, Taiwan M.T. Chien, C.K. Li 29 Photo
14 2018 Germany Munich, Germany D.Farenick, D.Kribs, C.K.Li, S. Plosker, T. Schulte-Herbruggen 32 Photo
15 2019 Japan Kawagoe, Japan C.K. Li, H. Nakazato, H. Osaka, T. Yamazaki 38 Photo
16 2023 Portugal Coimbra, Portugal N. Bebiano, R. Lemos, A. Nata, G. Soares 25 Photo
17 2025 Taiwan Taichung, Taiwan R.K. Lee, C.K. Li, N.S. Sze, M.C. Tsai, Y.S. Wang, N.C. Wong 50 Photo

Symposium in conferences

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Year Location Conferences Organizer(s)
1991 United States Minneapolis, USA Fourth SIAM Conference on Applied Linear Algebra C.K. Li
2007 China Shanghai, China International Linear Algebra Society Conference C.K. Li

References

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  1. ^ Bhatia, R. (1997). Matrix Analysis. Springer-Verlag. p. 349. ISBN 978-0387948461.
  2. ^ Bonsall, F.; Duncan, J. (1971). Numerical Ranges of Operators on Normed Spaces and of Elements of Normed Algebras. Cambridge University Press. p. 148. ISBN 978-0521079884.
  3. ^ Bonsall, F.; Duncan, J. (1973). Numerical Ranges II, Vol. 2. Cambridge University Press. p. 179. ISBN 978-0521202275.
  4. ^ Gustafson, K.E.; Rao, D.K.M. (1997). Numerical Range: The Field of Values of Linear Operators and Matrices. Springer-Verlag. p. 190. ISBN 978-0387948355.
  5. ^ Istratescu, B. (1982). Introduction to Linear Operator Theory. Marcel Dekker. p. 608. ISBN 978-0824768966.
  6. ^ Halmos, P.R. (1982). A Hilbert Space Problem Book. Graduate Texts in Mathematics. Vol. 19. Springer-Verlag. p. 373. doi:10.1007/978-1-4615-9976-0. ISBN 978-0387906850.
  7. ^ Horn, R.A.; Johnson, C.R. (1991). Topics in Matrix Analysis. Cambridge University Press. pp. 616. ISBN 978-0521467131.
  8. ^ Ando, T.; Li, C.K., eds. (1994). "Special issue devoted to WONRA". Linear and Multilinear Algebra. 37 (1–3).
  9. ^ Ando, T.; Li, C.K., eds. (1998). "Special issue devoted to WONRA". Linear and Multilinear Algebra. 43 (4).
  10. ^ Li, C.K.; Tam, T.Y., eds. (2006). "Special issue devoted to WONRA". Linear and Multilinear Algebra. 52 (3–4).
  11. ^ Li, C.K.; Tam, T.Y., eds. (2009). "Special issue devoted to WONRA". Linear and Multilinear Algebra. 57 (5).
[edit]

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Wikipedia

Numerical range

In the mathematical field of linear algebra and convex analysis, the numerical range or field of values or Wertvorrat or Wertevorrat of a complex n × n {\displaystyle n\times n} matrix A is the set W ( A ) = { x ∗ A x x ∗ x | x ∈ C n , x ≠ 0 } = { ⟨ x , A x ⟩ | x ∈ C n , ‖ x ‖ 2 = 1 } {\displaystyle W(A)=\left.\left\{{\frac {\mathbf {x} ^{*}A\mathbf {x} }{\mathbf {x} ^{*}\mathbf {x} }}\;\right|\;\mathbf {x} \in \mathbb {C} ^{n},\ \mathbf {x} \neq 0\right\}={\big \{}\langle \mathbf {x} ,A\mathbf {x} \rangle \;{\big |}\;\mathbf {x} \in \mathbb {C} ^{n},\ \|\mathbf {x} \|_{2}=1{\big \}}} where x ∗ {\displaystyle \mathbf {x} ^{*}} denotes the conjugate transpose of the vector x {\displaystyle \mathbf {x} } . The numerical range includes, in particular, the diagonal entries of the matrix (obtained by choosing x equal to the unit vectors along the coordinate axes) and the eigenvalues of the matrix (obtained by choosing x equal to the eigenvectors). Equivalently, the elements of W ( A ) {\displaystyle W(A)} are of the form tr ⁡ ( A P ) {\displaystyle \operatorname {tr} (AP)} , where P {\displaystyle P} is a Hermitian projection operator from C n {\displaystyle \mathbb {C} ^{n}} to a one-dimensional subspace. In engineering, numerical ranges are used as a rough estimate of eigenvalues of A. Recently, generalizations of the numerical range are used to study quantum computing. A related concept is the numerical radius, which is the largest absolute value of the numbers in the numerical range, i.e. r ( A ) = sup { | λ | : λ ∈ W ( A ) } = sup ‖ x ‖ 2 = 1 | ⟨ x , A x ⟩ | . {\displaystyle r(A)=\sup {\big \{}|\lambda |:\lambda \in W(A){\big \}}=\sup _{\|x\|_{2}=1}{\big |}\langle \mathbf {x} ,A\mathbf {x} \rangle {\big |}.}

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Wikipedia

Product numerical range

Given a Hilbert space with a tensor product structure a product numerical range is defined as a numerical range with respect to the subset of product vectors. In some situations, especially in the context of quantum mechanics product numerical range is known as local numerical range

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Wikipedia

Workshop on Numerical Ranges and Numerical Radii

Workshop on Numerical Ranges and Numerical Radii (WONRA) is a biennial workshop series on numerical ranges and numerical radii which began in 1992.

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Wikipedia

LMS color space

LMS (long, medium, short), is a color space which represents the response of the three types of cone cells of the human eye, named for their responsivity (sensitivity) peaks at long, medium, and short wavelengths. The numerical range is generally not specified, except that the lower end is generally bounded by zero. It is common to use the LMS color space when performing chromatic adaptation (estimating the appearance of a sample under a different illuminant). It is also useful in the study of color blindness, when one or more cone types are defective.

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TOPIC OF THE DAY

Greenwood / Black Wall Street

Before the 1921 destruction of Tulsa’s Greenwood District, Black residents had created a remarkable center of business and community life. The district included stores, professional offices, entertainment venues and homes owned by Black citizens. Understanding Greenwood means learning what was built—not only what was burned.

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TRIVIA QUESTION OF THE DAY

Which heavyweight champion was known as the “Brown Bomber”?

Joe Louis.