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21.
A polyphase filtering topology is proposed which uses parallel switchable RC-networks for accurate broadband 90∘ phasing. A 0.13μm CMOS prototype using the quadrature-generation network in a direct-conversion quadrature-modulator achieves
a measured image-rejection ratio of −39 dBc or better in 0.6–2.5 GHz while consuming only 66 mW from a 2.2 V single supply.
Esa Tiiliharjuwas born in Rovaniemi, Finland, in 1966. He received the M.Sc. degree in Information Technology in 1995, and the Lic.Tech
degree in electrical engineering in 1998, both from Helsinki University of Technology, Finland.
From 1996 to July 1997 he was employed as an assistant at Helsinki University of Technology. He has held a position as a research
assistant since 1997, and he is currently working towards his Ph.D. degree in the Electronic Circuit Design Laboratory at
Helsinki University of Technology.
His research interests include the design of integrated low-power circuits for portable telecommunication applications. He
has designed and measured several integrated circuits for this application area. He is the author or co-author of several
internationally-refereed conference and journal publications on analog integrated circuits.
Kari A.I. Halonenwas born in Helsinki, Finland, on May 23, 1958. He received the M.Sc. degree in electrical engineering from the Helsinki University
of Technology (HUT) in 1982 and the Ph.D. degree in electrical engineering from the Katholieke Universiteit Leuven, Heverlee,
Belgium, in 1987.
From 1982 to 1984, he was with HUT as an Assistant and with the Technical Research Center of Finland as a Research Assistant.
From 1984 to 1987, he was a Research Assistant with the E.S.A.T. Laboratory, Katholieke Universiteit Leuven, with a temporary
grant from the Academy of Finland. Since 1988, he has been with the Electronic Circuit Design Laboratory, HUT, as a Senior
Assistant from 1988 to 1990, and as the Director of the Integrated Circuit Design Unit of the Microelectronics Center from
1990 to 1993. He was on leave of absence during the academic year 1992–1993, acting as Research and Development Manager with
Fincitec Inc., Finland. From 1993 to 1996, he was an Associate Professor, and since 1997, he has been a full Professor with
the Faculty of Electrical Engineering and Telecommunications, HUT. He became the Head of Electronic Circuit Design Laboratory
year 1998. He was the Technical Program Committee Chairman for the European Solid-State Circuits Conference in 2000. He is
the author or coauthor of over 150 international and national conference and journal publications on analog integrated circuits,
and holds several patents on analog integrated circuits. His research interests are in CMOS and BiCMOS analog integrated circuits,
particularly for telecommunication applications.
Dr. Halonen was an Associate Editor of the IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS–PART I: FUNDAMENTAL THEORY AND APPLICATIONS
from 1997 to 1999. He has been a Guest Editor for the IEEE JOURNAL OF SOLID-STATE CIRCUITS. He received the BeatriceWinner
Award from the IEEE International Solid-State Circuits Conference in 2002.[c-halonen.eps] 相似文献
22.
Tapio Pulli 《Microelectronics Reliability》1985,25(6):1067-1071
The reliabilities of a three-state device and redundant structures of two such devices are considered, and it is shown that although the two failure modes were equally probable there may be advantages in using redundancy of two devices in series or parallel. It is also shown that the optimal redundant structure of two devices is not solely dependent on the failure mode distribution of the device. 相似文献
23.
24.
Telle-Hansen VH Larsen LN Høstmark AT Molin M Dahl L Almendingen K Ulven SM 《Lipids》2012,47(2):151-160
Intake of fish and omega-3 (n-3) fatty acids is associated with a reduced concentration of plasma triacylglycerols (TAG) but
the mechanisms are not fully clarified. Stearoyl-CoA desaturase-1 (SCD1) activity, governing TAG synthesis, is affected by
n-3 fatty acids. Peripheral blood mononuclear cells (PBMC) display expression of genes involved in lipid metabolism. The aim
of the present study was to estimate whether intake of lean and fatty fish would influence n-3 fatty acids composition in
plasma phospholipids (PL), serum TAG, 18:1n-9/18:0 ratio in plasma PL, as well as PBMC gene expression of SCD1 and fatty acid
synthase (FAS). Healthy males and females (n = 30), aged 20–40, consumed either 150 g of cod, salmon, or potato (control) daily for 15 days. During intervention docosahexaenoic
acid (DHA, 22:6n-3) increased in the cod group (P < 0.05), while TAG concentration decreased (P < 0.05). In the salmon group both eicosapentaenoic acid (EPA, 20:5n-3) and DHA increased (P < 0.05) whereas TAG concentration and the 18:1n-9/18:0 ratio decreased (P < 0.05). Reduction of the 18:1n-9/18:0 ratio was associated with a corresponding lowering of TAG (P < 0.05) and an increase in EPA and DHA (P < 0.05). The mRNA levels of SCD1 and FAS in PBMC were not significantly altered after intake of cod or salmon when compared
with the control group. In conclusion, both lean and fatty fish may lower TAG, possibly by reducing the 18:1n-9/18:0 ratio
related to allosteric inhibition of SCD1 activity, rather than by influencing the synthesis of enzyme protein. 相似文献
25.
We have studied how different catalysts and diols affect the properties of low-molecular-weight (Mw (GPC) < 49800 g/mol) lactic-acid-based telechelic prepolymers. The catalysts and diols were tested separately in our previous studies. In this study, we used the best previously tested diols and catalysts together in order to prepare different types of telechelic prepolymers (for example, crystalline or amorphous). All condensation polymerizations were carried out in the melt, using different diols and different catalysts. The prepolymers were characterized by differential scanning calorimetry, gel permeation chromatography, titrimetric methods, and 13C nuclear magnetic resonance (13C-NMR). According to NMR, the resulting polymers contained less than 1 mol % of lactic acid monomer and less than 5.1 mol % of lactide. Dibutyltindilaurate, like tin(II)octoate, produced quite good molecular weights, but the resulting prepolymers contained exceptionally high amounts of D-lactic acid structures, and, therefore, these prepolymers were totally amorphous. Antimony(III)oxide produced a high-molecular-weight prepolymer when the diol used was aliphatic. Like DBTL, Sb2O3 produced amorphous prepolymers, which contained a lower amount of D-lactic acid structures than DBTL prepolymers. 1,8-dihydroxyanthraquinone produced a different kind of chain structure with Ti(IV)bu and Ti(IV)iso because one prepolymer had high crystallinity, and the other showed only a slight crystallinity. Sulphuric acid produced a very high-molecular-weight prepolymer with aliphatic 2-ethyl-1,3-hexanediol; and with aromatic diols, it produced quite good molecular weights, except with 1,8-dihydroxyanthraquinone. High-molecular-weight prepolymers produced with H2SO4 also showed high crystallinity; and, according to 13C-NMR, they did not contain lactide and D-lactic acid structures. © 1998 John Wiley & Sons, Inc. J Appl Polm Sci 67:1011–1016, 1998 相似文献
26.
27.
Rönnholm Mats R. Hernández Carucci José R. Arve Kalle Eränen Kari Salmi Tapio 《Topics in Catalysis》2007,42(1-4):195-198
A silver/alumina catalyst was tested for its NO
x
reduction activity during oxygen-rich conditions and during variation in the input parameters (nitric oxide, octane and oxygen).
The experimental data using the microreactor was investigated by means of artificial neural networks (ANN). 相似文献
28.
Víctor A. Sifontes Herrera Farhan Saleem Bright Kusema Kari Er?nen Tapio Salmi 《Topics in Catalysis》2012,55(7-10):550-555
Complete hydrogenation of d-galactose and l-arabinose mixtures on a Ru/C catalyst was achieved with excellent selectivities exceeding 95?%. No unexpected effects of temperature and pressure were observed. A detailed kinetic model was derived to describe the simultaneous hydrogenation of the monomeric sugars. 相似文献
29.
Ville Alopaeus Jukka Koskinen Kari I. Keskinen 《Chemical Engineering Communications》2003,190(11):1468-1484
A simulation model has been developed to model drop populations in a mixed tank. A multiblock mixed tank model has been used with the drop population balance equations developed in the literature. The drop breakage and coalescence functions used in the population balance model take into account the local turbulent energy dissipation values. The drop breakage and coalescence function parameters are fitted against drop size measurements from dense liquid-liquid dispersions, which were assumed fully turbulent. Since the local turbulence and flow values of a mixed tank are used in the present model, the fundamental breakage and coalescence phenomena can be taken into closer examination. Furthermore, the present model is capable of predicting inhomogeneities occurring in a mixed tank. It is also considered as an improved tool for process scale-up, compared to the simple vessel-averaged population balance approach, or use of correlations of dimensionless numbers only. The present model can use two sources of data for fitting parameters in the drop rate functions. One is the transient data of the measured drop size distribution as the impeller speed is changed. The other is the time-averaged data measured at different locations of the mixed tank. Different flow regions can be chosen from direct measurements or from the CFD simulations in a straightforward manner. CFD flow simulation results can be used when no experimentally obtained flow conditions are available. This is especially useful for nonstandard vessels, such as reactors containing cooling coils. 相似文献
30.