Digital Library of Zielona Góra

Collections
- Jednostki organizacyjne (75)
  - Wydział Informatyki, Elektrotechniki i Automatyki (69)
  - Wydział Mechaniczny (4)
  - Wydział Budownictwa, Architektury i Inżynierii Środowiska (2)
- Typy utworów (75)
  - Artykuły (75)
- Czasopisma naukowe i serie wydawnicze UZ (68)
  - International Journal of Applied Mathematics and Computer Science (AMCS) (62)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2002) (6)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2009) (6)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (1999) (5)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2001) (4)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2014) (4)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2005) (3)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2006) (3)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2012) (3)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2000) (3)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2003) (3)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2008) (3)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2025) (3)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (1996) (2)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2016) (2)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2018) (2)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2022) (2)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2010) (1)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2011) (1)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2007) (1)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2017) (1)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2019) (1)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2021) (1)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2023) (1)
    - International Journal of Applied Mathematics and Computer Science (AMCS) (2024) (1)
  - International Journal of Applied Mechanics and Engineering (IJAME) (4)
    - International Journal of Applied Mechanics and Engineering (IJAME) (2022) (1)
    - International Journal of Applied Mechanics and Engineering (IJAME) (2020) (1)
    - International Journal of Applied Mechanics and Engineering (IJAME) (2017) (1)
    - International Journal of Applied Mechanics and Engineering (IJAME) (2016) (1)
  - Civil and Environmental Engineering Reports (CEER) (2)
    - Civil and Environmental Engineering Reports (CEER) (2021) (1)
    - Civil and Environmental Engineering Reports (CEER) (2022) (1)
Group objects
- International Journal of Applied Mathematics and Computer Science (AMCS) (62)
- International Journal of Applied Mechanics and Engineering (IJAME) (4)
- Civil and Environmental Engineering Reports (CEER) (2)
File type
- application/pdf (75)
Autor
- Paszke, Wojciech (1975- ) (6)
- Sokołowski, Jan (5)
- Tao, Hongfeng (5)
- Chen, Yiyang (3)
- Kowalewski, Adam (3)
- Rachik, Mostafa (3)
- Rogers, Eric (3)
- Stojanovic, Vladimir (3)
- Charef, Abdelfettah (2)
- Gugat, Martin (2)
- Gáspár, Péter (2)
- Hao, Shoulin (2)
- Horn, Werner (2)
- Kowalczuk, Zdzisław (2)
- Krakowiak, Anna (2)
- Marcinowski, Jakub (2)
- Sadowski, Mirosław (2)
- Zhuang, Zhihe (2)
- Świerniak, Andrzej (1950- ) (2)
- Abdelhak, Ahmed (1)
- Aboula?ch, Rajae (1)
- Aboulaich, Rajae (1)
- Ahmida, Zahir (1)
- Al-Hadithi, Basil Mohammed (1)
- Aldila, Dipo (1)
- Antoniades, Charalambos (1)
- Arechavaleta, Gustavo (1)
- Aschemann, Harald (1)
- Assawinchaichote, Wudhichai (1)
- Azelmat, Karim (1)
- Balluchi, Andrea (1)
- Baranger, Jacques (1)
- Barciński, Tomasz (1)
- Bars, Ruth (1)
- Bartoszewicz, Andrzej (1)
- Becerra, Victor M. (1)
- Bernal, Miguel (1)
- Bicchi, Antonio (1)
- Blizorukova, Marina (1)
- Bokor, József (1)
- Boldrini, Jose L. (1)
- Bourray, Hamid (1)
- Chabir, Karim (1)
- Chaoui, Kamel (1)
- Chra?bi, Lotfi (1)
- Christofides, Panagiotis D. (1)
- Costa, Michel I.S. (1)
- Czornik, Adam (1)
- Daley, Steve (1)
- Desjwiandra, Bevina (1)
- Di Trapani, Lyall Jonathan (1)
- Djouani, Karim (1)
- Dąbrowska, Olga (1)
- El Kahlaoui, Ouafa (1)
- El Yacoubi, Samira (1)
- Emirsajłow, Zbigniew (1)
- Fu, Xingjian (1)
- Fulmański, Piotr (1)
- Galicki, Mirosław (1)
- Georgiou, Tryphon T. (1)
- Haber, Robert (1)
- Haddad, A. (1)
- Haggouch, Ilham (1)
- Hajdu, Sándor (1)
- Hendzel, Zenon (1)
- Henrot, Antoine (1)
- Horla, Dariusz (1)
- Huang, Yande (1)
- Idczak, Dariusz (1)
- Iguernane, Mohamed (1)
- Inanc, Tamer (1)
- Jacewicz, Edyta (1)
- Jank, Gerhard (1)
- Jasińska, Dorota (1)
- Jha, Mayank Shekhar (1)
- Jiménez, Agustín (1)
- Jourhmane, Hasna (1)
- Kanso, Soha (1)
- Kappel, Franz (1)
- Karrakchou, Jamila (1)
- Khotimah, Khusnul (1)
- Khoury, Boutrous (1)
- Khrouf, F. (1)
- Kieffer, Michel (1)
- Klimkowicz, Kamil (1)
- Kogeda, Okuthe P. (1)
- Kostin, Georgy V. (1)
- Kukurowski, Norbert (1)
- Kurina, Galina (1)
- Labriji, Elhoussine (1)
- Ladaci, Samir (1)
- Latawiec, Krzysztof J. (1)
- Laurain, Antoine (1)
- Lazar, Martin (1)
- Ledzewicz, Urszula (1)
- Lengyel, Orsolya (1)
- Leśniewski, Piotr (1)
- Lhous, Mustapha (1)
- Liu, Tao (1)
- Loiseau, Jean Jacques (1)
Współtwórca
- Korbicz, Józef (1951- ) - red. (34)
- Uciński, Dariusz - red. (33)
- Korbicz, Józef (1951- ) - ed. (5)
- Jurczak, Paweł - red. (4)
- Sokołowski, Jan - ed. (3)
- Campagner, Andrea - ed. (2)
- Gałkowski, Krzysztof - ed. (2)
- Kowalczuk, Zdzisław - red. (2)
- Kuczyński, Tadeusz - red. (2)
- Lenz, Oliver Urs - ed. (2)
- Maksimov, Vyacheslav I. - ed. (2)
- Rogers, Eric - ed. (2)
- Sauter, Dominique - ed. (2)
- Stetter, Ralf - ed. (2)
- Triggiani, Roberto- ed. (2)
- Witczak, Marcin - ed. (2)
- Xia, Shuyin - ed. (2)
- Aitouche, Abdel - ed. (1)
- Aubrun, Christophe - ed. (1)
- Auer, Ekaterina - ed. (1)
- Bartłomiejczyk, Agnieszka - ed. (1)
- Fliess, Michel - ed. (1)
- Foryś, Urszula - ed. (1)
- Hofer,Eberhard P. - ed. (1)
- Hsu, Ching-Hsien - ed. (1)
- Jai, Abdelhaq El - ed. (1)
- Kacprzyk, Janusz - ed. (1)
- Kasiński, Andrzej - ed. (1)
- Kimmel, Marek - red. (1)
- Kobusińska, Anna - ed. (1)
- Kowal, Marek - red. (1)
- Lachowicz, Mirosław - red. (1)
- Lin, Kwei-Jay - ed. (1)
- Longman, Richard W. - ed. (1)
- Luther, Wolfram - ed. (1)
- Ponulak, Filip - ed. (1)
- Puig, Vicenç - ed. (1)
- Pękala, Barbara - ed. (1)
- Rauh, Andreas - ed. (1)
- Rejniak, Katarzyna - ed. (1)
- Rutkowska, Danuta - ed. (1)
- Schulte, Horst - ed. (1)
- Sonnendrücker, Eric - ed. (1)
- Willems, Jan (1)
- Zadeh, Lotfi A. - ed. (1)
- Zieliński, Cezary - ed. (1)
- Świerniak, Andrzej - red. (1)
Tytuł
- A level set method in shape and topology optimization for variational inequalities (1)
- A method for constructing [epsilon]-value functions for the Bolza problem of optimal control (1)
- A modified filter sqp method as a tool for optimal control of nonlinear systems with spatio-temporal dynamics (1)
- A novel method for the design of switching surfaces for discretized MIMO nonlinear systems (1)
- A problem of robust control of a system with time delay (1)
- A quadratic optimal control problem for a class of linear discrete distributed systems (1)
- A robust asymptotic tracking controller for an uncertain 2DOF underactuated mechanical system motivated by a satellite attitude control problem (1)
- An algorithm for construction of ?-value functions for the Bolza control problem (1)
- An application of optimal control theory to the design of theoretical schedules of anticancer drugs (1)
- An elastic membrane with an attached non-linear thermoelastic rod (1)
- An integrodifferential approach to modeling, control, state estimation and optimization for heat transfer systems (1)
- An optimal iterative learning control approach for linear systems with nonuniform trial lengths under input constraints (1)
- An optimal sliding mode congestion controller for connection-oriented communication networks with lossy links (1)
- Analytic interpolation and the degree constraint (1)
- Analyzing the MERS disease control strategy through an optimal control problem (1)
- Application of differential games in mechatronic control system (1)
- Approximation of a solidification problem (1)
- Controllability, observability and optimal control of continuous-time 2-D systems (1)
- DMOC-based robot trajectory optimization with analytical first-order information (1)
- Decentralized variable structure tracking for systems with time-domain dominance (1)
- Degradation tolerant optimal control design for stochastic linear systems (1)
- Designing of Steel CHS Columns Showing Maximum Compression Resistance (1)
- Discrete-time predictive control with overparameterized delay-plant models and an identified cancellation order (1)
- Domain optimization problem for stationary heat equation (1)
- Domain optimization problems for parabolic control systems (1)
- EHMAC ? A new simple tool for robust linear multivariable control (1)
- Fault detection based on interval observers and dynamic event-triggered fault-tolerant control for morphing aircraft (1)
- Fault diagnosis in a networked control system under communication constraints: A quadrotor application (1)
- Fault-tolerant tracking control for a non-linear twin-rotor system under ellipsoidal bounding (1)
- Further results on robust fuzzy dynamic systems with LMI D-stability constraints (1)
- Improving the generalization ability of neuro-fuzzy systems by [epsilon]-insensitive learning (1)
- Iterative learning control - monotonicity and optimization (1)
- Iterative learning control for repetitive tasks with randomly varying trial lengths using successive projection (1)
- Joint queue-perturbed and weakly coupled power control for Wireless Backbone Networks (1)
- Kinematically optimal robust control of redundant manipulators (1)
- LMI-based robust control of uncertain nonlinear systems via polytopes of polynomialsLMI-based robust control of uncertain nonlinear systems via polytopes of polynomials (1)
- LPV design of fault-tolerant control for road vehicles (1)
- Linear quadratic control problem with fixed final state for discrete-time distributed systems (1)
- Minimax LQG control (1)
- Modeling and optimization of cutting parameters when turning EN-AW-1350 aluminum alloy (1)
- NTGSIM: a graphical user interface and a 3d simulator for nonlinear trajectory generation methodology (1)
- On an infinite dimensional linear-quadratic problem with fixed endpoints: The continuity question (1)
- On directional change and anti-windup compensation in multivariable control systems (1)
- On the discrete time-varying JLQG problem (1)
- Optimal control for a class of compartmental models in cancer chemotherapy (1)
- Optimal control problems without terminal constraints: The turnpike property with interior decay (1)
- Optimal feedback control proportional to the system state can be found for non-causal descriptor systems (A remark on a paper by P.C. Müller) (1)
- Optimal internal dissipation of a damped wave equation using a topological approach (1)
- Optimal sensor selection for prediction-based iterative learning control of distributed parameter systems (1)
- Optimizing the linear quadratic minimum-time problem for discrete distributed systems (1)
- PI-Based Set-Point Learning Control for Batch Processes with Unknown Dynamics and Nonrepetitive Uncertainties (1)
- Point-to-Point Iterative Learning Control with Quantized Input Signal and Actuator Faults (1)
- Reducing the mast vibration of single-mast stacker cranes by gain-scheduled control (1)
- Regional control problem for distributed bilinear systems: approach and simulations (1)
- Reliability-aware zonotopic tube-based model predictive control of a drinking water network (1)
- Reliable robust path planning with application to mobile robots (1)
- Remarks about energy transfer in an RC ladder network (1)
- Repetitive process based indirect-type iterative learning control for batch processes with model uncertainty and input delay (1)
- Robust PD-type iterative learning control design for uncertain batch processes subject to nonrepetitive disturbances (1)
- Robust control of nonlinear time-delay systems (1)
- Robust fractional adaptive control based on the strictly positive realness condition (1)
- Shape optimization of labyrinth seals (1)
- Some issues in the design of predictive controllers (1)
- Stabilising solutions to a class of nonlinear optimal state tracking problems using radial basis function networks (1)
- Stability analysis of solutions to an optimal control problem associated with a Goursat-Darboux problem (1)
- Structure of Optimal Control in Optimal Shaping of the Steel Arch (1)
- Sub-optimal nonlinear predictive and adaptive control based on the parametric Volterra model (1)
- Suboptimal fault tolerant control design with the use of discrete optimization (1)
- Time-optimal boundary control of a parabolic system with time lags given in integral form (1)
- Time-optimal boundary control of an infinite order parabolic system with time lags (1)
- Time-optimal control of infinite order hyperbolic systems with time delays (1)
- Time-optimal control of linear fractional systems with variable coefficients (1)
- Topological derivatives for semilinear elliptic equations (1)
- Transient flow in gas networks: Traveling waves (1)
- Using the ERFI function in the problem of the shape optimization of the compressed rod (1)
Temat i słowa kluczowe
- optimal control (29)
- robust control (11)
- iterative learning control (7)
- shape optimization (7)
- predictive control (5)
- fault-tolerant control (3)
- nonlinear systems (3)
- topological derivative (3)
- Bolza problem (2)
- Hamilton-Jacobi equation (2)
- LPV systems (2)
- adaptive control (2)
- analytical approach (2)
- asymptotic analysis (2)
- batch processes (2)
- buckling criterion (2)
- controllability (2)
- distributed parameter systems (2)
- dynamic programming (2)
- fault detection (2)
- fractional calculus (2)
- infinite order (2)
- informatyka (2)
- matematyka stosowana (2)
- neural networks (2)
- non-linear optimisation (2)
- nonlinear control (2)
- nonuniform trial length (2)
- optimization (2)
- parabolic system (2)
- sterowanie (2)
- sterowanie-teoria (2)
- sztuczna inteligencja (2)
- time lags (2)
- time-optimal boundary control (2)
- variable structure control (VSC) (2)
- variational inequality (2)
- 2-D continuous-time systems (1)
- ANOVA (1)
- Artificial Neural Networks (ANN) (1)
- Bayesian theory (1)
- CHS section (1)
- D-stability (1)
- Erfi function (1)
- Euler method (1)
- Finite Element Method (FEM) (1)
- GUI (1)
- Goursat-Darboux problem (1)
- Hilbert uniqueness method (1)
- Java (1)
- Kalman filters (1)
- LMI approach (1)
- LMIs (1)
- LQG control (1)
- Lyapunov stability (1)
- MERS (1)
- MIMO systems (1)
- Navier-Stokes equations (1)
- PI controller tuning (1)
- Riemann-Liouville derivative (1)
- Stefan problem (1)
- Talagi-Sugeno fuzzy model (1)
- adaptive residual evaluation (1)
- analytic interpolation (1)
- approximate dynamic programming (1)
- approximate minimum (1)
- approximation of an RC-long line (1)
- arch (1)
- basic reproduction number (1)
- batch processes with unknown dynamics (1)
- bilinear systems (1)
- blow-up (1)
- campaign (1)
- cancer chemotherapy (1)
- chip shape (1)
- compartmental models (1)
- compressed bar (1)
- compressed rod (1)
- compressibility factor (1)
- continuity of optimal control (1)
- continuous dependence (1)
- coupled Riccati equations (1)
- data-driven control (1)
- decentralized control (1)
- decentralized power control (1)
- degradation (1)
- delay plants (1)
- differential games (1)
- discrete distributed system (1)
- discrete distributed systems (1)
- discrete mechanics and optimal control (1)
- discrete optimization (1)
- discrete sliding mode (1)
- discrete-time systems (1)
- distributed systems (1)
- dominance conditions (1)
- drinking water network (1)
- drug resistance (1)
- dynamic event-triggered (1)
- encoding-decoding mechanism (1)
Data wydania
- 2022 (7)
- 2002 (6)
- 2009 (6)
- 1999 (5)
- 2001 (4)
- 2014 (4)
- 2000 (3)
- 2003 (3)
- 2005 (3)
- 2006 (3)
- 2008 (3)
- 2012 (3)
- 2016 (3)
- 2021 (3)
- 2023 (3)
- 2025 (3)
- 1996 (2)
- 2017 (2)
- 2018 (2)
- 2024 (2)
- 2007 (1)
- 2010 (1)
- 2011 (1)
- 2019 (1)
- 2020 (1)
Typ zasobu
- artykuł (74)
Jezyk
- eng (75)
Prawa do dysponowania publikacją
- Biblioteka Uniwersytetu Zielonogórskiego (75)

Skip to main menu
Skip to search engine
Skip to content
Skip to footer

Items per page:

of 4 Next

AMCS, volume 19 (2009)

Topological derivatives for semilinear elliptic equations

Iguernane, Mohamed Nazarov, Serguei A. Roche, Jean-Rodolphe Sokołowski, Jan Szulc, Katarzyna Korbicz, Józef (1951- ) - ed.

2009

artykuł

AMCS, volume 17 (2007)

A level set method in shape and topology optimization for variational inequalities

Fulmański, Piotr Laurain, Antoine Scheid, Jean-Francois Sokołowski, Jan Sokołowski, Jan - ed. Sonnendrücker, Eric - ed.

2007

artykuł

CEER, nr 32, vol. 3 (2022)

Structure of Optimal Control in Optimal Shaping of the Steel Arch

Mikulski, Leszek Jasińska, Dorota Dąbrowska, Olga Kuczyński, Tadeusz - red.

2022

artykuł

IJAME, volume 22 (2017)

Kinematically optimal robust control of redundant manipulators

Galicki, Mirosław Jurczak, Paweł - red.

2017

artykuł

AMCS, volume 19 (2009)

Optimal internal dissipation of a damped wave equation using a topological approach

Münch, Arnaud Korbicz, Józef (1951- ) - ed.

2009

artykuł

AMCS, volume 18 (2008)

Iterative learning control - monotonicity and optimization

Owens, David H. Daley, Steve Gałkowski, Krzysztof - ed. Rogers, Eric - ed. Willems, Jan

2008

artykuł

AMCS, volume 9 (1999)

Decentralized variable structure tracking for systems with time-domain dominance

Balluchi, Andrea Bicchi, Antonio Korbicz, Józef (1951- ) - red. Uciński, Dariusz - red.

1999

artykuł

AMCS, volume 9 (1999)

Sub-optimal nonlinear predictive and adaptive control based on the parametric Volterra model

Haber, Robert Bars, Ruth Lengyel, Orsolya Kowalczuk, Zdzisław - red.

1999

artykuł

AMCS, volume 11 (2001)

A problem of robust control of a system with time delay

Blizorukova, Marina Kappel, Franz Maksimov, Vyacheslav I. Triggiani, Roberto- ed. Maksimov, Vyacheslav I. - ed.

2001

artykuł

AMCS, Volume 24 (2014)

An optimal sliding mode congestion controller for connection-oriented communication networks with lossy links

Bartoszewicz, Andrzej Leśniewski, Piotr Korbicz, Józef (1951- ) - red. Kowal, Marek - red.

2014

artykuł

Robust PD-type iterative learning control design for uncertain batch processes subject to nonrepetitive disturbances

Maniarski, Robert Paszke, Wojciech (1975- ) Hao, Shoulin Tao, Hongfeng

2022

AMCS, Volume 16 (2006)

Minimax LQG control

Petersen, Ian R. Korbicz, Józef (1951- ) - red. Uciński, Dariusz - red.

2006

artykuł

IJAME, volume 21 (2016)

Application of differential games in mechatronic control system

Hendzel, Zenon Penar, Paweł Jurczak, Paweł - red.

2016

artykuł

AMCS, volume 9 (1999)

An application of optimal control theory to the design of theoretical schedules of anticancer drugs

Boldrini, Jose L. Costa, Michel I.S. Korbicz, Józef (1951- ) - red. Uciński, Dariusz - red.

1999

artykuł

AMCS, volume 19 (2009)

On directional change and anti-windup compensation in multivariable control systems

Horla, Dariusz Korbicz, Józef (1951- ) - ed.

2009

artykuł

AMCS, Volume 20 (2010)

NTGSIM: a graphical user interface and a 3d simulator for nonlinear trajectory generation methodology

Di Trapani, Lyall Jonathan Inanc, Tamer Korbicz, Józef (1951- ) - red. Uciński, Dariusz - red.

2010

artykuł

AMCS, volume 13 (2003)

Stability analysis of solutions to an optimal control problem associated with a Goursat-Darboux problem

Idczak, Dariusz Majewski, Marek Walczak, Stanisław Gałkowski, Krzysztof - ed. Longman, Richard W. - ed. Rogers, Eric - ed.

2003

artykuł

AMCS, volume 12 (2002)

Optimal feedback control proportional to the system state can be found for non-causal descriptor systems (A remark on a paper by P.C. Müller)

Kurina, Galina Korbicz, Józef (1951- ) - red. Uciński, Dariusz - red.

2002

artykuł

AMCS, volume 10 (2000)

EHMAC ? A new simple tool for robust linear multivariable control

Latawiec, Krzysztof J. Rojek, Ryszard (1943- ) Korbicz, Józef (1951- ) - red. Uciński, Dariusz - red.

2000

artykuł

AMCS, volume 10 (2000)

Linear quadratic control problem with fixed final state for discrete-time distributed systems

Chra?bi, Lotfi Karrakchou, Jamila Ouansafi, Abdelatif Rachik, Mostafa Korbicz, Józef (1951- ) - red. Uciński, Dariusz - red.

2000

artykuł

Iterative learning control for repetitive tasks with randomly varying trial lengths using successive projection

Zhuang, Zhihe Tao, Hongfeng Chen, Yiyang Stojanovic, Vladimir Paszke, Wojciech (1975- )

2021

artykuł

An optimal iterative learning control approach for linear systems with nonuniform trial lengths under input constraints

Zhuang, Zhihe Tao, Hongfeng Chen, Yiyang Stojanovic, Vladimir Paszke, Wojciech (1975- )

2022

artykuł

AMCS, volume 35 (2025)

A robust asymptotic tracking controller for an uncertain 2DOF underactuated mechanical system motivated by a satellite attitude control problem

Emirsajłow, Zbigniew Barciński, Tomasz Campagner, Andrea - ed. Lenz, Oliver Urs - ed. Xia, Shuyin - ed.

2025

artykuł

IJAME, volume 27 (2022)

Modeling and optimization of cutting parameters when turning EN-AW-1350 aluminum alloy

Khrouf, F. Tebassi, Hamid Yallese, M.A. Chaoui, Kamel Haddad, A. Jurczak, Paweł - red.

2022

artykuł

Filters

Number of results: 75

Contact details

Address

Phone

E-Mail

Visit us!

Sitemap

Main page

Collections

Indexes

Informations

User's account

Recently viewed

Filters