Klaus Schittkowski

7.0k total citations · 4 hit papers
55 papers, 4.8k citations indexed

About

Klaus Schittkowski is a scholar working on Numerical Analysis, Computational Theory and Mathematics and Computational Mechanics. According to data from OpenAlex, Klaus Schittkowski has authored 55 papers receiving a total of 4.8k indexed citations (citations by other indexed papers that have themselves been cited), including 36 papers in Numerical Analysis, 21 papers in Computational Theory and Mathematics and 12 papers in Computational Mechanics. Recurrent topics in Klaus Schittkowski's work include Advanced Optimization Algorithms Research (26 papers), Numerical methods for differential equations (11 papers) and Advanced Control Systems Optimization (7 papers). Klaus Schittkowski is often cited by papers focused on Advanced Optimization Algorithms Research (26 papers), Numerical methods for differential equations (11 papers) and Advanced Control Systems Optimization (7 papers). Klaus Schittkowski collaborates with scholars based in Germany, Canada and Ireland. Klaus Schittkowski's co-authors include Willi Hock, William W. Hager, Hongchao Zhang, Yu‐Hong Dai, Thomas Lehmann, Hans P. Merkle, Josef Stoer, Jesús M. Frías, Jorge C. Oliveira and Frank Vogel and has published in prestigious journals such as European Journal of Operational Research, Industrial & Engineering Chemistry Research and Journal of Theoretical Biology.

In The Last Decade

Klaus Schittkowski

54 papers receiving 4.4k citations

Hit Papers

NLPQL: A fortran subroutine solving constrained nonlinear... 1981 2026 1996 2011 1986 1987 1986 1981 250 500 750
What are hit papers?

Hit papers significantly outperform the citation benchmark for their cohort. A paper qualifies if it has ≥500 total citations, achieves ≥1.5× the top-1% citation threshold for papers in the same subfield and year (this is the minimum needed to enter the top 1%, not the average within it), or reaches the top citation threshold in at least one of its specific research topics.

  1. NLPQL: A fortran subroutine solving constrained nonlinear programming problems
    1986 885 citations Klaus Schittkowski Annals of Operations Research profile →
  2. More Test Examples for Nonlinear Programming Codes
    1987 872 citations Klaus Schittkowski Lecture notes in economics and mathematical systems profile →
  3. NLPQL: A fortran subroutine solving constrained nonlinear programming problems
    1986 598 citations Klaus Schittkowski Annals of Operations Research profile →
  4. Test Examples for Nonlinear Programming Codes
    1981 483 citations Willi Hock, Klaus Schittkowski Lecture notes in economics and mathematical systems profile →

Peers — A (Enhanced Table)

Peers by citation overlap · career bar shows stage (early→late) cites · hero ref

Name h Career Trend Papers Cites
Klaus Schittkowski Germany 23 1.8k 1.7k 1.1k 651 633 55 4.8k
Virginia Torczon United States 23 2.2k 1.2× 1.1k 0.6× 802 0.7× 452 0.7× 445 0.7× 28 5.7k
Garth P. McCormick United States 23 2.1k 1.2× 2.2k 1.3× 1.6k 1.4× 550 0.8× 439 0.7× 47 5.4k
Christoph Witzgall United States 16 1.3k 0.7× 935 0.5× 733 0.6× 512 0.8× 265 0.4× 44 4.4k
E. Polak United States 41 3.3k 1.8× 3.1k 1.8× 2.6k 2.3× 1.3k 2.1× 703 1.1× 210 9.3k
Charles Audet Canada 33 1.9k 1.0× 1.4k 0.8× 1.0k 0.9× 441 0.7× 289 0.5× 143 5.1k
Andrew R. Conn United States 33 3.5k 1.9× 3.7k 2.1× 1.5k 1.3× 1.7k 2.5× 368 0.6× 91 8.4k
Anthony V. Fiacco United States 18 1.5k 0.8× 1.4k 0.8× 871 0.8× 382 0.6× 258 0.4× 50 3.3k
L. N. Vicente Portugal 32 2.0k 1.1× 1.7k 1.0× 1.0k 0.9× 748 1.1× 178 0.3× 94 4.6k
Florian A. Potra United States 34 1.8k 1.0× 2.2k 1.2× 915 0.8× 614 0.9× 228 0.4× 141 4.4k
Andreas Wächter United States 20 1.7k 1.0× 1.8k 1.0× 4.2k 3.7× 773 1.2× 512 0.8× 57 9.4k

Countries citing papers authored by Klaus Schittkowski

Since Specialization
Citations

This map shows the geographic impact of Klaus Schittkowski's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by Klaus Schittkowski with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites Klaus Schittkowski more than expected).

Fields of papers citing papers by Klaus Schittkowski

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by Klaus Schittkowski. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by Klaus Schittkowski. The network helps show where Klaus Schittkowski may publish in the future.

Co-authorship network of co-authors of Klaus Schittkowski

This figure shows the co-authorship network connecting the top 25 collaborators of Klaus Schittkowski. A scholar is included among the top collaborators of Klaus Schittkowski based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with Klaus Schittkowski. Klaus Schittkowski is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

20 of 20 papers shown
1.
Lehmann, Thomas, et al.. (2012). A comparative study of SQP-type algorithms for nonlinear and nonconvex mixed-integer optimization. Mathematical Programming Computation. 4(4). 383–412. 32 indexed citations
2.
Schittkowski, Klaus. (2010). A robust implementation of a sequential quadratic programming algorithm with successive error restoration. Optimization Letters. 5(2). 283–296. 21 indexed citations
3.
Dai, Yu‐Hong, William W. Hager, Klaus Schittkowski, & Hongchao Zhang. (2006). The cyclic Barzilai-–Borwein method for unconstrained optimization. IMA Journal of Numerical Analysis. 26(3). 604–627. 139 indexed citations
4.
Pesch, Hans Josef, et al.. (2003). Numerical Simulation of a 1D Model of a Molten Carbonate Fuel Cell. PAMM. 3(1). 521–522. 3 indexed citations
5.
Pesch, Hans Josef, et al.. (2003). Index Analysis of a Nonlinear PDAE System Describing a Molten CarbonateFuel Cell. PAMM. 3(1). 563–564. 2 indexed citations
6.
Schittkowski, Klaus. (2003). Data fitting in partial differential algebraic equations: some academic and industrial applications. Journal of Computational and Applied Mathematics. 163(1). 29–57. 2 indexed citations
7.
Schittkowski, Klaus. (2002). EASY-FIT: a software system for data fitting in dynamical systems. Structural and Multidisciplinary Optimization. 23(2). 153–169. 71 indexed citations
8.
Schittkowski, Klaus, et al.. (2000). Modeling of Diffusion and Concurrent Metabolism in Cutaneous Tissue. Journal of Theoretical Biology. 204(3). 393–407. 42 indexed citations
9.
Schittkowski, Klaus, et al.. (2000). Remark on algorithm 746. ACM Transactions on Mathematical Software. 26(3). 352–362. 1 indexed citations
10.
Schittkowski, Klaus, et al.. (1999). Computation of optimal feed rates and operation intervals for tubular reactors. Journal of Process Control. 9(4). 325–336. 10 indexed citations
11.
Schittkowski, Klaus. (1993). Mathematical optimization: an introduction. 110. 33–42. 4 indexed citations
12.
Schittkowski, Klaus. (1987). More Test Examples for Nonlinear Programming Codes. Lecture notes in economics and mathematical systems. 872 indexed citations breakdown →
13.
Schittkowski, Klaus. (1986). NLPQL: A fortran subroutine solving constrained nonlinear programming problems. Annals of Operations Research. 5(2). 485–500. 885 indexed citations breakdown →
14.
Schittkowski, Klaus. (1986). NLPQL: A fortran subroutine solving constrained nonlinear programming problems. Annals of Operations Research. 5(1-4). 485–500. 598 indexed citations breakdown →
15.
Schittkowski, Klaus. (1985). Computational Mathematical Programming. CERN Document Server (European Organization for Nuclear Research). 76 indexed citations
16.
Hock, Willi & Klaus Schittkowski. (1983). A comparative performance evaluation of 27 nonlinear programming codes. Computing. 30(4). 335–358. 125 indexed citations
17.
Hock, Willi & Klaus Schittkowski. (1981). Test Examples for Nonlinear Programming Codes. Lecture notes in economics and mathematical systems. 483 indexed citations breakdown →
18.
Hock, Willi & Klaus Schittkowski. (1980). Test examples for nonlinear programming codes. Journal of Optimization Theory and Applications. 30(1). 127–129. 221 indexed citations
19.
Schittkowski, Klaus. (1979). Numerical solution of a time-optimal parabolic boundary-value control problem. Journal of Optimization Theory and Applications. 27(2). 271–290. 17 indexed citations
20.
Schittkowski, Klaus & Josef Stoer. (1978). A factorization method for the solution of constrained linear least squares problems allowing subsequent data changes. Numerische Mathematik. 31(4). 431–463. 20 indexed citations

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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