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1997
Valtchev, Stanimir IEEE Meritorious Paper Award for 1996., 1997.
Louren{\c c}o, João, José C. Cunha, H. Krawczyk, P. Kuzora, M. Neyman, and B. Wiszniewski. "An integrated testing and debugging environment for parallel and distributed programs." EUROMICRO Conference (1997): 291. AbstractWebsite
To achieve a certain degree of confidence that a given program follows its specification, a testing phase must be included in the program development process, and also a complementary debugging phase to help locating the program’s bugs. This paper presents an environment which results of the composition and integration of two basic tools: STEPS (Structural TEsting of Parallel Software), which is a testing tool, and DDBG (Distributed DeBuGger), which is a debugging tool. The two tools are presented individually as stand-alone tools, and we describe how they were combined through the use of another intermediate tool: DEIPA (Deterministic re-Execution and Interactive Program Analysis). We claim that the result achieved is a very effective testing and debugging environment.
Fantoni, A., Vieira Cruz Martins M. J. R. "Modelling a μc-Si:H p-i-n device under non-uniform illumination." Thin Solid Films. 296 (1997): 110-113. AbstractWebsite

Microcrystalline p-i-n silicon devices are a prospective contender for application in large-area optoelectronics. In this paper we analyse the behaviour of a μc-Si:H p-i-n photodevice under non-uniform illumination. The effect of a spatially non-uniform illumination is to create lateral electric fields and current flows inside the structure. We present in this paper a numerical application of a complete bidimensional model describing the transport properties within the structure. The continuity equations forholes and electrons together with Poisson's equation are solved simultaneously along the two directions parallel and perpendicular to the junction. The results of simulating p-i-n μc-Si:H junctions under non-uniform illumination show that the generated lateral effects depend not only in intensity but also in direction on the wavelength of the incident radiation. © 1997 Elsevier Science S.A.

Borges, C., C. Caetano, JC Pessoa, MO Figueiredo, A. Lourenco, MM Gomes, TP Silva, and JP Veiga. "Monitoring the removal of soluble salts from ancient tiles by ion chromatography." Journal of Chromatography a. 770 (1997): 195-201. Abstract
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Borges, C., C. Caetano, J. Costa Pessoa, MO Figueiredo, A. Lourenço, Malhoa M. Gomes, TP Silva, and JP Veiga. "Monitoring the removal of soluble salts from ancient tiles by ion chromatography." Journal of Chromatography A. 770 (1997): 195-201. Abstract
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Tavares, P., AS Pereira, S. G. Lloyd, D. Danger, DE Edmondson, E. C. Theil, and BH HUYNH. "Mossbauer spectroscopic and kinetic characterization of ferric clusters formed in h-chain ferritin mineralization." Abstracts of Papers of the American Chemical Society. 213 (1997): 503-INOR. AbstractWebsite
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vanWesenbeeck, MPN, JB Klaassens, U. vonStockhausen, A. Muñoz De Morales Anciola, and SS Valtchev. "A multiple-switch high-voltage dc-dc converter." IEEE Transactions on Industrial Electronics. 44 (1997): 780-787. Abstract
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Rato, L., RN Silva, J. M. Lemos, and F. Coito. "Multirate MUSMAR cascade control of a distributed solar field." Proc. of the European Control Conference ECC97. Brussels, Belgium (1997). Abstract
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Fantoni, A., Vieira Cruz Martins M. J. R. "Numerical simulation of a/μc-Si:H p-i-n photo-diode under non-uniform illumination: A 2D transport problem." Proceedings of SPIE - The International Society for Optical Engineering. Vol. 2997. 1997. 234-243. Abstract

We report here about a computer simulation program, based on a comprehensive physical and numerical model of an a/μc-Si:H p-i-n device, applied to the 2D problem of describing the transport properties within the structure under non- uniform illumination. The continuity equations for holes and electrons together with Poisson's equation are solved simultaneously along the two directions parallel and perpendicular to the junction. The basic semiconductor equations are implemented with a recombination mechanism reflecting the microcrystalline structure of the different layers. The lateral effects occurring within the structure, due to the non-uniformity of the radiation are outlined. The simulation results obtained for different wavelengths of the incident light are compared and shown their dependence on the energy of the radiation. The results of simulating a p-i-n μc-Si:H junctions under non-uniform illumination is that the generated lateral effects depend not only in intensity but also in direction on the wavelength of the incident radiation. ©2004 Copyright SPIE - The International Society for Optical Engineering.

Dias, C. J., P. Inacio, J. N. MaratMendes, and D. K. Dasgupta. "Polarization and hysteresis in low resistivity ferroelectric composites." Ferroelectrics. 198 (1997): 121-130. AbstractWebsite
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Dias, C. J., P. Inacio, J. N. MaratMendes, and D. K. Dasgupta. "Polarization and hysteresis in low resistivity ferroelectric composites." Ferroelectrics. 198 (1997): 121-130. Abstract
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Igreja, R., C. J. Dias, and J. N. MaratMendes. "Processing and characterization of sol-gel derived modified PbTiO3 for ferroelectric composite applications." Journal of Sol-Gel Science and Technology. 8 (1997): 721-723. Abstract
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Igreja, R., C. J. Dias, and J. N. MaratMendes. "Processing and characterization of sol-gel derived modified PbTiO3 for ferroelectric composite applications." Journal of Sol-Gel Science and Technology. 8 (1997): 721-723. Abstract
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Igreja, R., C. J. Dias, and J. N. MaratMendes. "Processing and characterization of sol-gel derived modified PbTiO3 for ferroelectric composite applications." Journal of Sol-Gel Science and Technology. 8 (1997): 721-723. AbstractWebsite
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Pereira, AS, P. Tavares, S. G. Lloyd, D. Danger, DE Edmondson, E. C. Theil, and BH HUYNH. "Rapid and parallel formation of Fe3+ multimers, including a trimer, during H-type subunit ferritin mineralization." Biochemistry. 36 (1997): 7917-7927. AbstractWebsite

Conversion of Fe ions in solution to the solid phase in ferritin concentrates iron required for cell function. The rate of the Fe phase transition in ferritin is tissue specific and reflects the differential expression of two classes of ferritin subunits (H and L). Early stages of mineralization were probed by rapid freeze-quench Mossbauer, at strong fields (up to 8 T), and EPR spectroscopy in an H-type subunit, recombinant frog ferritin; small numbers of Fe (36 moles/mol of protein) were used to increase Fe3+ in mineral precursor forms, At 25 ms, four Fe3+-oxy species (three Fe dimers and one Fe trimer) were identified, These Fe3+-oxy species were found to form at similar rates and decay subsequently to a distinctive superparamagentic species designated the ''young core.'' The rate of oxidation of Fe2+ (1026 s(-1)) corresponded well to the formation constant for the Fe3+- tyrosinate complex (920 s(-1)) observed previously [Waldo, G. S., & Theil, E. C. (1993) Biochemistry 32, 13261] and, coupled with EPR data, indicates that several or possibly all of the Fe3+-oxy species involve tyrosine. The results, combined with previous Mossbauer studies of Y30F human H-type ferritin which showed decreases in several Fe3+ intermediates and stabilization of Fe2+ [Bauminger, E. R., et al. (1993) Biochem, J. 296, 709], emphasize the involvement of tyrosyl residues in the mineralization of H-type ferritins. The subsequent decay of these multiple Fe3+-oxy species to the superparamagnetic mineral suggests that Fe3+ species in different environments may be translocated as intact units from the protein shell into the ferritin cavity where the conversion to a solid mineral occurs.

Mateus, O., and J. J. Jacinto. "Ritmos de Actividade e habitat de Hemidactylus turcicus (Reptilia: Gekkonidae) em Évora, Portugal." Cuadernos de INICE. 74-75 (1997): 207-214. Abstract
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Martins, R., A. Maçarico, I. Ferreira, J. Fidalgo, and E. Fortunato. "Role of the deposition parameters in the uniformity of films produced by the plasma-enhanced chemical vapour deposition technique." Philosophical Magazine B. 76.3 (1997): 259-272. Abstract
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Martins, R., Maçarico Ferreira Fidalgo Fortunato A. I. J. "Role of the deposition parameters in the uniformity of films produced by the plasma-enhanced chemical vapour deposition technique." Philosophical Magazine B: Physics of Condensed Matter; Statistical Mechanics, Electronic, Optical and Magnetic Properties. 76 (1997): 259-272. AbstractWebsite

The objective of this work is to present an analytical model able to interpret the experimental dependence of the uniformity of films produced by the plasma-enhanced chemical vapour deposition technique on the deposition parameters (discharge pressure, gas flow temperature and rf power density). The model proposed is based on the Navier-Stokes equations applied to a gas flow considered to be quasi-incompressible and quasi-inviscous, whenever the Mach number is below 0·3. This condition leads to the establishment of the proper quasisteady-state gas flow equations, and the corresponding equations of energy and momentum balance ascribed to the mass profile of the species formed, under the presence of a low-rf-power plasma density, are able to predict the uniformity distribution of the film over the entire deposited substrate area.

Martins, R., A. Macarico, I. Ferreira, and E. Fortunato. "Role of the gas flow parameters on the uniformity of films produced by PECVD technique." MRS Proceedings. 467.1 (1997). Abstract
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Martins, R., Macarico Ferreira Fortunato A. I. E. "Role of the gas flow parameters on the uniformity of films produced by PECVD technique." Materials Research Society Symposium - Proceedings. Vol. 467. 1997. 609-614. Abstract

The aim of this work is to present an analytical model able to interpret the experimental data of the dependence of film's uniformity on the discharge pressure, gas flow and temperature used during the production of thin films by the plasma enhancement chemical vapour deposition technique, under optimised electrode's geometry and electric field distribution. To do so, the gas flow is considered to be quasi-incompressible and inviscous leading to the establishment of the electro-fluid-mechanics equations able to interpret the film's uniformity over the substrate area, when the discharge process takes place in the low power regime.

Moser, I., F. Mota-Furtado, P. F. O'Mahony, and J. P. Santos. "Rydberg wave packets in parallel electric and magnetic fields." Physical Review A. 55 (1997): 3724-3729. Abstract

The magnitude of the time autocorrelation function M between states excited by two Gaussian laser pulses is calculated for both hydrogen and rubidium atoms inparallel electric and magnetic fields. M is determined by a full quantum-mechanical calculation but the peaks are identified with the periods of the shortest periodicorbits of the corresponding classical system. Qualitative agreement is obtained with experimental results, however, discrepancies are found in the relative heights ofthe peaks.

Fernandes, Vitor H. "Semigroups of order preserving mappings on a finite chain: a new class of divisors." Semigroup Forum. 54 (1997): 230-236.Website
Riti, Jean-Bernard, M. T. Cidade, M. H. Godinho, AF Martins, and Patrick Navard. "Shear induced textures of thermotropic acetoxypropylcellulose." Journal of Rheology. 41.6 (1997): 1247-1260. Abstract
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Malik, A., Seco Nunes Vieira Fortunato Martins A. R. M. "Spray-deposited metal oxide films with various properties for micro- and optoelectronic applications: Growth and characterization." Materials Research Society Symposium - Proceedings. Vol. 471. 1997. 47-52. Abstract

This work reports the structure and electro-optical characteristics of different metal oxide films obtained by spray pyrolysis on heated glass substrates, aiming their application in optoelectronic devices. The results show that this technique leads to thin films with properties ranging from dielectric to degenerate semiconductors, offering the following advantages: simplicity, low cost, high productivity and the possibility of covering large areas, highly important for large area device applications.

Martins, R., A. Macarico, M. Vieira, I. Ferreira, and E. Fortunato. "Structure, composition and electro-optical properties of n-type amorphous and microcrystalline silicon thin films." Philosophical magazine B. 76.3 (1997): 249-258. Abstract
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