Dr Wlodek Tych

Research Fellow, Furness College Principal

Research Interests

Research:

My main interest and background is in developing methods and tools for time series analysis and in general analysis of uncertain dynamic and non-linear systems. The general thread in the apparently wide-ranging application areas I am involved in, is also modelling of complex natural dynamic systems while not denying the underlying uncertainties; and the effect of scale (both spatial and temporal) on the modelling process and model structure. The other fundamental element in these modelling exercises is their Data-Based Mechanistic character, whereby the model structure is not assumed, but identified using objective statistical criteria. Complexity of the model that is identifiable depends strongly on the available data - we can only model the modes of behaviour of the system under investigation that are present and 'visible' in the data. This approach to modelling is what brought me to Lancaster in the first place.

Development of novel methods of non-linear systems modelling and control (with Peter Young and Arun Chotai),

Ongoing development of Captain Toolbox

Modelling of hydrological processes (various joint projects with Nick Chappell)

Analysis of trends, cycles and interdependencies in long term environmental records (a number of projects, mostly with Nick Chappell and Crispin Halsall); these trend analysis methods have been recommended in the 2007 UNEP 'Air' Report.

Reversing hydrology: estimation of sub-hourly rainfall time-series from streamflow
Kretzschmar, A., Tych, W., Chappell, N.A. 10/2014 In: Environmental Modelling and Software. 60, p. 290-301. 12 p.
Journal article

A simple transfer-function-based approach for estimating material parameters from terahertz time-domain data
Tych, K., Wood, C., Tych, W. 02/2014 In: IEEE Photonics Journal. 6, 1
Journal article

First dynamic model of dissolved organic carbon derived directly from high frequency observations through contiguous storms
Jones, T.D., Chappell, N.A., Tych, W. 2014 In: Environmental Science and Technology. 48, p. 13289-13297.
Journal article

Data-Based Mechanistic modelling of rainfall to riverflow of large nested tropical rainforest catchments in Ghana.
Ampadu, B., Chappell, N., Tych, W. 06/2013 In: Canadian Journal of Pure and Applied Sciences. 7, 2, p. 2405-2424. 20 p.
Journal article

Calibrated digital images of Campbell–Stokes recorder card archives for direct solar irradiance studies
Horseman, A., Richardson, T., Boardman, T., Tych, W., Timmis, R., Mackenzie, R. 23/05/2013 In: Atmospheric Measurement Techniques. 6, 5, p. 1371-1379. 9 p.
Journal article

Rainfall-riverflow modelling approaches: making a choice of data-based mechanistic modelling approach for data limited catchments: a review.
Ampadu, B., Chappell, N., Tych, W. 2013 In: Canadian Journal of Pure and Applied Sciences. 7, 3, p. 2571-2580.
Journal article

Extending Manley’s Lancashire Plain Temperature Record: 1753‐2007
Gormally, A., Mackenzie, R., Tych, W. 10/2012 In: International Journal of Climatology. 32, 12, p. 1899-1908. 10 p.
Journal article

A matlab software framework for dynamic model emulation
Tych, W., Young, P.C. 1/06/2012 In: Environmental Modelling and Software. 34, n/a, p. 19-29. 11 p.
Journal article

Temporal trends of persistent organic pollutants: a comparison of different time series models.
Venier, M., Hung, H., Tych, W., Hites, R. 3/04/2012 In: Environmental Science and Technology. 46, 7, p. 3928-3934. 7 p.
Journal article

Identifying step changes in single streamflow and evaporation records due to forest cover change.
Chappell, N.A., Tych, W. 01/2012 In: Hydrological Processes. 26, 1, p. 100-116. 17 p.
Journal article

Changing sources and environmental factors reduce the rates of decline of organochlorine pesticides in the Arctic atmosphere
Becker, S., Halsall, C., Tych, W., Kallenborn, R., Schlabach, M., Mano, S. 2012 In: Atmospheric Chemistry and Physics . 12, n/a, p. 4033-4044. 12 p.
Journal article

Linear and nonlinear non-minimal state space control system design.
Taylor, C.J., Chotai, A., Tych, W. 2012 In: System Identification, Environmental Modelling and Control System Design. London : Springer p. 559-582. 24 p. ISBN: 978-0857299734.
Chapter

Multi-State-Dependent parameter model identification and estimation.
Tych, W., Sadeghi, J., Smith, P., Chotai, A., Taylor, C.J. 2012 In: System Identification, Environmental Modelling and Control System Design. London : Springer p. 191-210. 20 p. ISBN: 978-0-85729-973-4.
Chapter

Tropical cyclone effects on rapid runoff responses: quantifying with new continuous-time transfer function models
Chappell, N.A., Bonell, M., Barnes, C., Tych, W. 2012 In: Revisiting Experimental Catchment Studies in Forest Hydrology. Wallingford : IAHS Press p. 82-93. 12 p.
Chapter (peer-reviewed)

Longer-term responses of rainforest erosional systems at different spatial scales to selective logging and climatic change
Walsh, R.P.D., Bidin, K., Blake, W.H., Chappell, N.A., Clarke, M.A., Douglas, I., Ghazali, R., Sayer, A.M., Suhaimi, J., Tych, W., Annammala, K.V. 2011 In: Philosophical transactions of the Royal Society of London. Series B, Biological sciences. 366, n/a, p. 3340-3353. 14 p.
Journal article

River sediment monitoring for baseline and change characterisation: a new management tool for the Ramu River Communities in Papua New Guinea
Chappell, N.A., Tych, W., Shearman, P., Lokes, B., Chitoa, J. 2011 In: Sediment Problems and Sediment Management in Asian River Basins. Wallingford : IAHS Press p. 92-102. 11 p.
Chapter (peer-reviewed)

Multi-state dependent parameter model identification and estimation for nonlinear dynamic systems.
Sadeghi, J., Tych, W., Chotai, A., Young, P.C. 09/2010 In: Electronics Letters. 46, 18, p. 1265-1266. 2 p.
Journal article

The Captain toolbox.
Young, P.C., Taylor, C.J., Tych, W., Pedregal, D.J., McKenna, P.G. 2010
Software

Changing sources and environmental factors reduce the rates of decline of organochlorine pesticides in the Arctic Atmosphere.
Becker, S., Halsall, C.J., Tych, W., Kallenborn, R., Schlabach, M., Manø, S. 2009 In: Atmospheric Chemistry and Physics Discussions. 9, 1, p. 515-540. 26 p.
Journal article

Simulating hourly rainfall occurrence within an equatorial rainforest, Borneo Island
Chappell, N.A., Discenza, A.R., Tych, W., Whittaker, J., Bidin, K. 2009 In: Hydrological Sciences Journal. 54, 3, p. 571-581. 11 p.
Journal article

The Captain Toolbox for Matlab
Young, P., Tych, W., Taylor, J. 2009
Other

The provision of site specific flood warnings using wireless sensor networks.
Smith, P.J., Beven, K.J., Tych, W., Hughes, D., Coulson, G., Blair, G. 2009 In: Flood risk management : research and practice. London : CRC Press 309 p. ISBN: 9780415485074.
Chapter

Understanding small-scale features in DGT measurements in sediments.
Sochaczewski, Ł., Davison, W., Zhang, H., Tych, W. 2009 In: Environmental Chemistry. 6, 6, p. 477-485. 9 p.
Journal article

Long-term trends in a- and g-HCH in the arctic atmosphere: the effect of legislation and climate fluctuations on atmospheric concentrations.
Becker, S., Halsall, C.J., Tych, W., Kallenborn, R., Su, Y., Hung, H. 11/2008 In: Atmospheric Environment. 42, 35, p. 8225-8233. 9 p.
Journal article

Managing heterogeneous data flows in wireless sensor networks using a 'split personality' mote platform.
Hughes, D., Daude, M., Coulson, G., Blair, G., Smith, P., Beven, K., Tych, W. 07/2008 In: International Symposium on Applications and the Internet, 2008. SAINT 2008.. IEEE p. 145-148. 4 p.
Paper

A three-dimensional reactive transport model for sediments, incorporating microniches.
Sochaczewski, Ł., Stockdale, A., Davison, W., Tych, W., Zhang, H. 19/06/2008 In: Environmental Chemistry. 5, 3, p. 218-225. 8 p.
Journal article

Quantitative assessment of soil parameter (KD and TC) estimation using DGT measurements and the 2D DIFS model.
Lehto, N.J., Sochaczewski, Ł., Davison, W., Tych, W., Zhang, H. 03/2008 In: Chemosphere. 71, 4, p. 795-801. 7 p.
Journal article

The provision of site specific flood warnings using wireless sensor networks.
Smith, P.J., Beven, K.J., Tych, W., Hughes, D., Coulson, G., Blair, G. 2008 In: Proceedings of FLOODRisk 2008.
Chapter

Development of the forSIM model to quantify positive and negative hydrological impacts of tropical reforestation.
Chappell, N.A., Tych, W., Bonell, M. 30/10/2007 In: Forest Ecology and Management. 251, 1-2, p. 52-64. 13 p.
Journal article

Environmental Time Series Analysis and Forecasting with the Captain Toolbox
Taylor, C.J., Pedregal, D.J., Young, P.C., Tych, W. 1/06/2007 In: Environmental Modelling and Software. 22, 6, p. 797-814. 18 p.
Journal article

2D DGT induced fluxes in sediments and soils (2D DIFS).
Sochaczewski, Ł., Tych, W., Davison, B., Zhang, H. 01/2007 In: Environmental Modelling and Software. 22, 1, p. 14-23. 10 p.
Journal article

Identification of diurnal, seasonal and inter-annual variability across SE Asian field observations of key water cycle variables : rainfall, net radiation, total evaporation and river discharge.
Solera-Garcia, M.A., Chappell, N., Tych, W. 2007
Abstract

Identification of the distribution of hydro-climatic cycles of field observations in Southeast Asia.
Solera Garcia, M.A., Chappell, N., Tych, W. 11/2006 In: Climate variability and change. Wallingford : IAHS Publications p. 356-361. 6 p. ISBN: 9781901502787.
Chapter

An evaluation of DGT performance using a dynamic numerical model.
Lehto, N.J., Davison, W., Zhang, H., Tych, W. 15/10/2006 In: Environmental Science and Technology. 40, 20, p. 6368-6376. 9 p.
Journal article

Theoretical comparison of how soil processes affect uptake of metals by diffusive gradients in thinfilms and plants.
Lehto, N.J., Davison, W., Zhang, H., Tych, W. 10/2006 In: Journal of Environmental Quality. 35, 5, p. 1903-1913. 11 p.
Journal article

Resolving the long-term trend of PAHs in the Canadian Arctic atmosphere.
Becker, S., Halsall, C.J., Tych, W., Hung, H., Attewell, S., Blanchard, P., Li, H., Fellin, P., Stern, G., Billeck, B., Friesen, S. 05/2006 In: Environmental Science and Technology. 40, 10, p. 3217-3222. 6 p.
Journal article

Analysis of Micro-Nutrient Behaviour in the Rhizosphere using a DGT Parameterised Dynamic Plant Uptake Model
Lehto, N.J., Davison, W., Zhang, H., Tych, W. 04/2006 In: Plant and Soil. 282, 1-2, p. 227-238. 12 p.
Journal article

BARUMODEL: Combined Data Based Mechanistic models of runoff response in a managed rainforest catchment. Forest Ecology and Management.
Chappell, N.A., Bidin, K., Chotai, A., Tych, W. 15/03/2006 In: Forest Ecology and Management. 224, 1-2, p. 58-80. 23 p.
Journal article

Forecasting method selection : advantages and limitations.
Tych, W., Fildes, R.A., Hibon, M. 2006 In: Proceedings in the International Symposium on Forecasting.
Chapter

Identification of the distribution of hydroclimatic cycles of field observations in Southeast Asia.
Solera-Garcia, M., Chappell, N.A., Tych, W. 2006 In: Climate variability and change : hydrological impacts. Wallingford : International Association of Hydrological Sciences p. 356-361. 6 p. ISBN: 9781901502787.
Chapter

Linear, nonlinear and classical control of a 1/5th scale automated excavator.
Taylor, C.J., Sidiropoulou, E., Shaban, E.M., Tych, W., Chotai, A. 2006 In: Proceedings of the 18th international conference on systems engineering (ICSE-06)..
Conference contribution

The hydraulic scaling of step-pool systems.
Carling, P.A., Tych, W., Richardson, K. 2005 In: River, coastal and estuarine morphodynamics. New York : Taylor & Francis p. 55-63. 9 p. ISBN: 0415393752.
Chapter

Source of suspended-sediment within a tropical catchment recovering from selective logging.
Chappell, N.A., Douglas, I., Hanapi, J.M., Tych, W. 03/2004 In: Hydrological Processes. 18, 4, p. 685-701. 17 p.
Journal article

Effect of natural climatic cycles on rainfall-stream runoff (P-Q) of a 44 ha catchment recovering from selective tropical forestry.
Bidin, K., Chappell, N.A., Tych, W., Greer, T. 2004 In: Forests and water in warm, humid Asia (Proceedings of a IUFRO Forest Hydrology Workshop, 10-12 July 2004, Kota Kinabalu, Malaysia, Disaster Prevention Research Institute). Uiji, Japan : Disaster Prevention Research Institute p. 204-207. 4 p. ISBN: 499021420X.
Chapter

New approach to modelling water paths in managed rainforests.
Chappell, N.A., Tych, W., Chotai, A., Bidin, K., Sinun, W., Thang, H.C. 2004 In: Forests and water in warm, humid Asia (Proceedings of a IUFRO Forest Hydrology Workshop, 10-12 July 2004, Kota Kinabalu, Malaysia, Disaster Prevention Research Institute). Uiji, Japan : Disaster Prevention Research Institute p. 256-259. 4 p. ISBN: 499021420X.
Chapter

Spatially-significant effects of selective tropical forestry on water, nutrient and sediment flows: a modelling-supported review
Chappell, N.A., Tych, W. 2004 In: Forests, water and people in the humid Tropics : past, present, and future hydrological research for intergrated land and water management. Cambridge : Cambridge University Press p. 513-532. 20 p. ISBN: 0521829534.
Chapter

Statistical modelling of rainfall and river flow in Thailand.
Boochabun, K., Tych, W., Chappell, N.A., Carling, P.A., Lorsirirat, K., Pa-Obsaeng, S. 2004 In: Journal of the Geological Society of India. 64, p. 503-515. 13 p.
Journal article

New modelling techniques in the analysis of tropical climate data.
Tych, W., Chappell, N.A. 24/03/2003
Conference paper

Identification of land-use change impacts on tropical hydrological processes.
Chappell, N.A., Tych, W. 2003
Conference paper

Statistical modelling for rainfall and river flow in Thailand.
Buchaboon, K., Tych, W., Chappell, N.A., Carling, P. 12/2002
Conference paper

An unobserved component model for multi-rate forecasting of telephone call demand : the design of a forecasting support system.
Tych, W., Pedregal, D.J., Young, P.C., Davies, J. 10/2002 In: International Journal of Forecasting. 18, 4, p. 673-695. 23 p.
Journal article

Relations between a multivariate ENSO index and atmospheric deposition near Atlanta, Georgia, 1986-2002.
Peters, N.E., Tych, W. 09/2002
Conference paper

The benefits of model choice.
Fildes, R., Tych, W., Hibon, M. 06/2002
Conference paper

Sodium-related partial stomatal closure and salt tolerance of Aster tripolium
Kerstiens, G., Tych, W., Robinson, M.F., Mansfield, T.A. 03/2002 In: New Phytologist. 153, 3, p. 509-515. 7 p.
Journal article

Climate cycle and land-use change sensitivity of tropical hydrological systems : a precursor to GCM land-use change simulations.
Chappell, N.A., Tych, W. 2002 In: UGAMP Newsletter. 25, p. 11-11. 1 p.
Journal article

Modelling rainfall and canopy controls on net-precipitation beneath selectively-logged tropical forest.
Chappell, N.A., Bidin, K., Tych, W. 04/2001 In: Plant Ecology. 153, 1-2, p. 215-229. 15 p.
Journal article

Intra-catchment dynamics of water and sediment.
Chappell, N.A., Tych, W., Douglas, I. 2001 In: Transactions of the Japanese Geomorphological Union. 22, 4, p. C38.
Journal article

Modelling rainfall and canopy controls on net-precipitation beneath selectively-logged tropical forest.
Chappell, N.A., Bidin, K., Tych, W. 2001 In: Tropical forest canopies : ecology and management. Dordrecht : Kluwer Academic Publishers ISBN: 079237049X.
Chapter

DIFS - a modelling and simulation tool for DGT induced trace metal remobilisation in sediments and soils.
Harper, M.P., Davison, W., Tych, W. 01/2000 In: Environmental Modelling and Software. 15, 1, p. 55-66. 12 p.
Journal article

Estimation of pore water concentrations from DGT profiles : a modelling approach.
Harper, M.P., Davison, W., Tych, W. 12/1999 In: Aquatic Geochemistry. 5, 4, p. 337-355. 19 p.
Journal article

Dynamic harmonic regression.
Young, P.C., Pedregal, D., Tych, W. 11/1999 In: Journal of Forecasting. 18, 6, p. 369-394. 26 p.
Journal article

One-dimensional views of three-dimensional sediments.
Harper, M.P., Davison, W., Tych, W. 1/08/1999 In: Environmental Science and Technology. 33, 15, p. 2611-2616. 6 p.
Journal article

Characterising solute transport in undisturbed soil cores using electrical and x-ray tomographic methods.
Olsen, P.A., Binley, A.M., Henry-Poulter, S., Tych, W. 15/02/1999 In: Hydrological Processes. 13, 2, p. 211-221. 11 p.
Journal article

Simulation of lava tube growth using stochastic cellular automata models.
Pinkerton, H., Tych, W., Kent, R., Calvari, S. 1999 In: Geophysical Research Abstracts. 1, 4, p. 861-861. 1 p.
Journal article

Kinetics of metal exchange between solids and solutions in sediments and soils interpreted from DGT measured fluxes.
Harper, M., Davison, W., Zhang, H., Tych, W. 08/1998 In: Geochimica et Cosmochimica Acta. 62, 16, p. 2757-2770. 14 p.
Journal article

Proportional-integral-plus (PIP) design for delta (d ) operator systems : part 1, SISO systems.
Young, P.C., Chotai, A., McKenna, P., Tych, W. 05/1998 In: International Journal of Control. 70, 1, p. 123-147. 25 p.
Journal article

Proportional-integral-plus (PIP) design for delta (d ) operator systems: part 2, MIMO systems.
Chotai, A., Young, P.C., McKenna, P., Tych, W. 05/1998 In: International Journal of Control. 70, 1, p. 149-168. 20 p.
Journal article

A software package for multi-rate unobserved component forecasting of telephone call demand.
Tych, W., Young, P.C., Pedregal, D.J., Davies, J. 1998
Conference paper

Temporal, spatial, and resolution constraints for in situ sampling devices using diffusion equilibration : dialysis and DET.
Harper, M.P., Davison, W., Tych, W. 11/1997 In: Environmental Science and Technology. 31, 11, p. 3110-3119. 10 p.
Journal article

Sorption of trace metasl (Cu, Pb, Zn) by suspended lake particles in artificial (0.05 M NaNO3) and natural (Esthwaite Water) freshwaters.
Hamilton-Taylor, J., Guisti, L., Davison, W., Tych, W., Hewitt, C. 21/02/1997 In: Colloids and Surfaces A: Physicochemical and Engineering Aspects. 120, 1-3, p. 205-219. 15 p.
Journal article

Operational control of water systems : structures, algorithms and applications by M. A. Brdys and B. Ulanicki.
Young, P.C., Tych, W. 11/1996 In: Automatica. 32, 11, p. 1619-1620. 2 p.
Journal article

Design and implementation of a proportional-integral-plus (PIP) control system for temperature, humidity and carbon dioxide in a glasshouse.
Lees, M.J., Taylor, J., Chotai, A., Young, P.C., Chalabi, Z.S., Tych, W. 1996 In: Acta Horticulturae. 406, p. 115-124. 10 p.
Journal article

TDC : computer aided true digital control of multivariable delta operator.
Tych, W., Young, P.C., Chotai, A., Jones, L.C. 1996
Conference paper

Texture dependence of the persistent NMR signal in superfluid3He-B.
Bunkov, Y.M., Cousins, D.J., Enrico, M.P., Fisher, S.N., Pickett, G.R., Shaw, N.S., Tych, W. 1996 In: Czechoslovak Journal of Physics. 46, S1, p. 233-234. 2 p.
Journal article

The importance of structure in PIP control design.
Taylor, C.J., Young, P.C., Chotai, A., Tych, W., Lees, M.J. 1996 In: UKACC International Control Conference. p. 1196-1201. 6 p.
Conference contribution

In situ high resolution measurements of fluxes of Ni, Cu, Fe, and Mn and concentrations of Zn and Cd in porewaters by DGT.
Zhang, H., Davison, W., Miller, S., Tych, W. 10/1995 In: Geochimica et Cosmochimica Acta. 59, 20, p. 4181-4192. 12 p.
Journal article

A non-minimal state variable feedback approach to multivariable control of glasshouse climate.
Lees, M.J., Young, P.C., Chotai, A., Tych, W. 1995 In: Transactions of the Institute of Measurement and Control. 17, 4, p. 200-211. 12 p.
Journal article

Computer aided control system design of PIP controllers for systems described by delta operator and backward shift models.
Tych, W., Young, P.C., Chotai, A., Lees, M.J. 1994
Conference paper

Modelling and PIP control of a glasshouse micro-climate.
Young, P.C., Lees, M.J., Chotai, A., Tych, W., Chalabi, Z.S. 1994 In: Control Engineering Practice. 2, 4, p. 591-604. 14 p.
Journal article

Identification, estimation and true digital control of glasshouse systems.
Young, P.C., Chotai, A., Tych, W. 1993 In: The computerized greenhouse : automatic control application in plant production. Academic Press p. 3-50. 48 p.
Chapter

True digital CACSD package in Matlab/Simulab environment.
Tych, W., Young, P.C., Chotai, A. 1992 In: IEE Colloquium Digest on Computer Aided Control Systems Design, Algorithms, Packages and Environments. 1992, 4, p. 3/1-3/9.
Journal article

Adaptive true digital control (TDC) of continuous-time systems using -operator models.
Young, P.C., Chotai, A., Tych, W. 1991 In: Identification and system parameter estimation. Oxford : Pergamon Press p. 1166-1173. 8 p.
Chapter

Computer aided design package for true digital control (TDC) systems.
Tych, W., Chotai, A., Young, P.C. 1991 In: Control 1991 : International Conference on Control '91. IEEE p. 288-293. 6 p. ISBN: 0-85296-509-5.
Chapter

Identification, estimation and control of continuous-time systems described by delta operator models.
Young, P.C., Chotai, A., Tych, W. 1991 In: Identification of continuous time systems. Dordrecht : Kluwer Academic Publishers p. 363-418. 56 p.
Chapter

Identification, estimation and control of glasshouse systems.
Young, P.C., Tych, W., Chotai, A. 1991 In: Mathematical and Control Applications in Agriculture and Horticulture. Oxford : Pergamon Press p. 307-316. 10 p.
Chapter

TDC : a computer aided control design package for true digital control.
Tych, W., Young, P.C., Chotai, A. 1991 In: Computer aided design in control systems. Oxford : Pergamon Press p. 454-459. 6 p.
Chapter

Mathematical modelling of the reaction latency. Part III : a model of avoidance reaction latency and avoidance learning.
Pacut, A., Tych, W. 1982 In: Acta Neurobiologiae Experimentalis. 42, 4-5, p. 397-420. 24 p.
Journal article

Response properties of neurons in the inferior colliculus of the guinea-pig.
Popelar, J., Syka, J., Dobrzanska, J., Pacut, A., Tych, W. 1982 In: Acta Neurobiologiae Experimentalis. 42, 4-5, p. 299-310. 12 p.
Journal article