document

Combining semi-distributed process-based and data-driven models in flow simulation: A case study of the Meuse river basin

Corzo, G.A. (author), Solomatine, D.P. (author), Hidayat, M.S. (author), De Wit, M. (author), Werner, M. (author), Uhlenbrook, S. (author), Price, R.K. (author)

One of the challenges in river flow simulation modelling is increasing the accuracy of forecasts. This paper explores the complementary use of data-driven models, e.g. artificial neural networks (ANN) to improve the flow simulation accuracy of a semi-distributed process-based model. The IHMS-HBV model of the Meuse river basin is used in this...

journal article 2009

document

Evaluatie sleutelprojecten: Onderzoek in opdracht van het Ministerie van VROM

Van der Wouden, R. (author), Spaans, M. (author), Foeken, G. (author), Hollander, K. (author), Trip, J.J. (author), Milder, J. (author), De Wit, P. (author)

In de Structuurvisie Randstad 2040 kondigt het kabinet aan om een verkenning te overwegen naar Randstad-sleutelprojecten voor de periode na 2020. Voorafgaand aan het besluit om een dergelijke verkenning daadwerkelijk te starten, wordt een evaluatieonderzoek uitgevoerd naar de eerste generatie- en tweede generatie sleutelprojecten. Een aantal...

report 2009

document

Zinc Composite Layers, Incorporating Polymeric Nano-aggregates: Surface Analysis and Electrochemical Behavior

Koleva, D.A. (author), Zhang, X. (author), Petrov, P. (author), Boshkov, N. (author), Van Breugel, K. (author), De Wit, J.H.W. (author), Mol, J.M.C. (author), Tsvetkova, N. (author)

This study reports on a comparative investigation of the corrosion behavior of zinc (Zn) and nano-composite zinc (ZnC) galvanic layers in 5% NaCl solution. The metallic matrix of the ZnC layers incorporates nano-sized, stabilized polymeric aggregates, formed from the amphiphilic tri-block co-polymer: poly(2-hydroxyethyl methacrylate) - poly ...

journal article 2008

document

Corrosion Behavior of Steel re-bars in Mortar, Containing Waste Products

Koleva, D.A. (author), Van Breugel, K. (author), De Wit, J.H.W. (author)

journal article 2008

document

Electrochemical Impedance and Potentio-Dynamic Polarization of Construction Steel in Cement Extract, Containing Red Mud and Chloride Contamination

Koleva, D.A. (author), Copuroglu, O. (author), Van Breugel, K. (author), De Wit, J.H.W. (author)

journal article 2008

document

Het succes van DSS: Leerervaringen van ontwikkeling van Decision Support Systems in dynamische multiactor context

Karstens, S. (author), Willems, M. (author), Rietveld, E. (author), Sman, B. (author), De Wit, S. (author)

Iedereen neemt elke dag beslissingen variërend van hoe naar het werk te gaan tot wat eten met de lunch. Ondanks dat voor een deel het nemen van beslissingen ook een kwestie van geluk is, is het belangrijk om bij het nemen van goede beslissingen gebruik te maken van beschikbare en relevante informatie waar we onze keuzes op kunnen baseren....

report 2008

document

Clinical effects of transcatheter hepatic arterial embolization with holmium-166 poly(l-lactic acid) microspheres in healthy pigs

Vente, M.A.D. (author), Nijsen, J.F.W. (author), De Wit, T.C. (author), Seppenwoolde, J.H. (author), Krijger, G.C. (author), Seevinck, P.R. (author), Huisman, A. (author), Zonneneberg, B.A. (author), Van den Ingh, T.S.G.A.M. (author), Van het Schip, A.D. (author)

Purpose The aim of this study is to evaluate the toxicity of holmium-166 poly(l-lactic acid) microspheres administered into the hepatic artery in pigs. Methods Healthy pigs (20–30 kg) were injected into the hepatic artery with holmium-165-loaded microspheres (165HoMS; n?=?5) or with holmium-166-loaded microspheres (166HoMS; n?=?13). The...

journal article 2008

document

Degradation of myocardial perfusion SPECT images caused by contaminants in thallous (201Tl) chloride

Staelens, S.G. (author), De Wit, T.C. (author), Lemahieu, I.A. (author), Beekman, F.J. (author)

Purpose Thallous (201Tl) chloride is a single-photon emission computed tomography (SPECT) tracer mainly used for assessing perfusion and viability of myocardial tissue. 201Tl emits X-rays around 72 keV and gammas at 167 keV, and has a half-life of 73 h. Regulations allow an intrinsic contamination up to 3–5%, which is mainly caused by 200Tl (368...

journal article 2008

document

Composition and Morphology of Product Layers in the Steel/Cement Paste Interface in Conditions of Corrosion and Cathodic Protection in Reinforced Concrete

Koleva, D.A. (author), Van Breugel, K. (author), De Wit, J.H.W. (author), Fraaij, A.L.A. (author), Boshkov, N. (author)

The present study explores the formation of corrosion products on the steel surface in reinforced concrete in conditions of corrosion and subsequent transformation of these layers in conditions of cathodic protection (CP). Of particular interest was to investigate if the introduced pulse CP (as cost- effective alternative of CP) will lead to...

journal article 2007

document

Application of Electrochemical Impedance Spectroscopy in the Evaluation of Corrosion and Cathodic Protection in Reinforced Concrete

Koleva, D.A. (author), Van Breugel, K. (author), De Wit, J.H.W. (author), Fraaij, A.L.A. (author), Boshkov, N. (author)

The electrochemical behavior of steel reinforcement in conditions of corrosion and cathodic protection (CP) was studied, using electrochemical impedance spectroscopy (EIS) and compared to reference (non-corroding) conditions. Polarization resistance (PR) method and potentio-dynamic polarization (PDP) were employed as well, in addition to AC 2...

journal article 2007

document

Electrochemical Measurements in Cement Extract Solutions on Reinforcing Steel, Previously Conditioned in Concrete

Koleva, D.A. (author), De Wit, J.H.W. (author), Van Breugel, K. (author), Bachvarov, V. (author), Kolev, H. (author), Fraaij, A. (author)

The corrosion behavior of reinforcing steel, previously embedded in concrete and maintained in conditions of corrosion and two regimes (conventional and pulse) of cathodic protection (CP), was characterized using electrochemical measurements in cement extract (CE) solutions of pH 12.6. The investigation aimed at determination of the properties...

journal article 2007

document

A Combined Electrochemical and Microstructural Analysis of Model AlMgSi(Cu) Alloys

Zhan, H. (author), Mol, J.M.C. (author), Terryn, H.A. (author), De Wit, J.H.W. (author)

Application prospects in automotive and aerospace industry have led to extensive studies on AA6xxx alloys in recent years because of their attractive combinations of properties. The benefits include formability, weldability, high strength to weight ratio and low cost. The main alloying elements in the commercial AA6xxx are Mg, Si, Fe and Cu. Mg...

journal article 2007

document

Controlling and Probing the Nano Interaction Between Organic Molecules and Al Alloys

Blajiev, O. (author), Hauffman, T. (author), De Wit, J.H.W. (author), Snauwaert, J. (author), Hubin, A. (author)

journal article 2007

document

Apparatus for cathodic protection of steel reinforced concrete structures and method

Koleva, D.A. (author), Hu, J. (author), Van Beek, K. (author), Van Breugel, K. (author), De Wit, J.H.W. (author)

patent 2007

document

Investigation of Corrosion and Cathodic Protection in Reinforced Concrete. II: Properties of Steel Surface Layers

Koleva, D.A. (author), De Wit, J.H.W. (author), Van Breugel, K. (author), Lodhi, Z.F. (author), Ye, G. (author)

The present study explores the formation of corrosion products on the steel surface (using as-received low carbon construction steel) in reinforced concrete in conditions of corrosion and subsequent transformation of these layers in conditions of cathodic protection (CP).

journal article 2007

document

Investigation of Corrosion and Cathodic Protection in Reinforced Concrete. I: Application of Electrochemical Techniques

Koleva, D.A. (author), De Wit, J.H.W. (author), Van Breugel, K. (author), Lodhi, Z.F. (author), Van Westing, E. (author)

The electrochemical behavior of steel reinforcement in conditions of corrosion and cathodic protection was studied, using electrochemical impedance spectroscopy (EIS) and compared to reference (noncorroding) conditions. Polarization resistance (PR) method and potentiodynamic polarization (PDP) were employed as well, in addition to ac 2 pin...

journal article 2007

document

Electrochemical Behavior, Microstructural Analysis, and Morphological Observations in Reinforced Mortar Subjected to Chloride Ingress

Koleva, D.A. (author), Van breugel, K. (author), De Wit, J.H.W. (author), Van Westing, E. (author), Boshkov, N. (author), Fraaij, A.L.A. (author)

The behavior of steel reinforcement was studied using electrochemical impedance spectroscopy (EIS) and polarization resistance (PR) techniques in conditions of chloride-induced corrosion in ordinary Portland cement-mortar specimens immersed in 7% NaCl for a test period of 120 days and compared to specimens immersed in demineralized water for the...

journal article 2007

document

Conventional and Pulse Cathodic Protection of Reinforced Concrete: Electrochemical Approach and Microstructural Investigations

Koleva, D.A. (author), Hu, J. (author), Van Breugel, K. (author), De Wit, J.H.W. (author), Boshkov, N. (author)

An improved cathodic protection (CP), based on pulse regime was investigated in reinforced concrete, compared to conventional CP. Both regimes used CP current in the range of 2 to15 mA/m2. A voltage-to-current converter maintained the pulse current, the latter adjusted with duty cycle of 12% to 50 % and frequency of 500 Hz to 1 kHz. The...

journal article 2006

document

Drying Effects on Corrosion Properties of Cr(VI) and Cr(III) Treated Electrogalvanized Steel

Zhang, X. (author), Van den Bos, C. (author), Sloof, W.G. (author), Hovestad, A. (author), Terryn, H. (author), De Wit, J.H.W. (author)

Drying effects on corrosion performance of Cr(VI)- and Cr(III)-treated electro-galvanized steel have been studied in NaCl solution using potentiodynamic measurements and electrochemical impedance spectroscopy (EIS). The Cr(VI) and the Cr(III) treated specimens were dried at three different temperatures: 60, 110 and 210°C. The surface layers were...

journal article 2006

document

Electrochemical Measurements on Previously Conditioned in Concrete Reinforcing Steel in Cement Extract Solutions

Koleva, D.A. (author), Van Breugel, K. (author), De Wit, J.H.W. (author), Bachvarov, V. (author)

journal article 2006