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1.
Kurjenniemi Janne Hämäläinen Seppo Ristaniemi Tapani 《Wireless Personal Communications》2003,27(4):337-351
In this article we consider the performance of the 3.84 Mcpstime-division duplex (TDD) mode of UTRA (Universal TerrestrialRadio Access) network. We emphasize two of the radio resourcemanagement algorithms, handover and uplink power control, whoserole in the overall system performance is studied extensively.First, a handover algorithm used in WCDMA (Wideband Code DivisionMultiple Access) standard is considered in a TDD-mode operation.This gives rise to a careful setting of different handoverparameters, and the evaluation of the effects to the systemperformance. Secondly, the specified uplink power controlalgorithm is considered. Since it is based on several user-mademeasurements which may involve both random and systematic errors acareful study about the suitability of the power control scheme iscarried out. 相似文献
2.
Seppo Hassi Manfred Mö ller Henk de Snoo 《Proceedings of the American Mathematical Society》2006,134(10):2885-2893
The class of Nevanlinna functions consists of functions which are holomorphic off the real axis, which are symmetric with respect to the real axis, and whose imaginary part is nonnegative in the upper halfplane. The Kac subclass of Nevanlinna functions is defined by an integrability condition on the imaginary part. In this note a further subclass of these Kac functions is introduced. It involves an integrability condition on the modulus of the Nevanlinna functions (instead of the imaginary part). The characteristic properties of this class are investigated. The definition of the new class is motivated by the fact that the Titchmarsh-Weyl coefficients of various classes of Sturm-Liouville problems (under mild conditions on the coefficients) actually belong to this class.
3.
The effects of four wash procedures on the concentration of chromium in a pooled sample of human scalp hair are compared. The wash solutions examined are Triton X-100, sodium lauryl sulphate, acetone, and a mixture (1 + 1) of hexane and ethanol. The plateaux reached for hair chromium concentration are functions of the number of washings, and are characteristic for each wash solution. The wash procedure recommended involves two 20-min washes with aqueous 1% sodium lauryl sulphate solution after a hexane rinse. 相似文献
4.
Dr. Seppo Seikkala 《Monatshefte für Mathematik》1982,93(3):225-238
We shall derive existence, uniqueness and comparison results for the functional differential equationx(t)=f(t, x), a. e.tI, with classical Nicoletti boundary conditionsx
i(ti)=y
iX, iA, whereI is a real interval,A is a nonempty set andX is a Banach space. 相似文献
5.
Antti Ruha Juha Kostamovaara Seppo Säynäjäkangas 《Analog Integrated Circuits and Signal Processing》1994,5(2):147-168
A micropower detector chip integrated with CMOS technology has been developed for a hand-held heart rate monitoring instrument mainly used by professional athletes and others who exercise seriously to increase their endurance and overall performance. The chip uses linear bandpass filtering and threshold detection and is implemented with analog switched-capacitor (SC) and digital techniques. The bandpass filter transfer function is derived from the spectral contents of noisy ECG signals. The layout was designed in full custom style in order to minimize the silicon area. The chip achieves a detection rate of 90% with a simulated ECG signal corrupted with Gaussian noise (signal-to-noise ratio = 5) in the heart rate range 60-200 1/min with a total current consumption of less than 30µA from a 3-V supply. The detection rate is 96.9% for a noisy signal obtained from the MIT-BIH arrhythmia database. 相似文献
6.
Ferenets R Lipping T Anier A Jäntti V Melto S Hovilehto S 《IEEE transactions on bio-medical engineering》2006,53(6):1067-1077
Entropy and complexity of the electroencephalogram (EEG) have recently been proposed as measures of depth of anesthesia and sedation. Using surrogate data of predefined spectrum and probability distribution we show that the various algorithms used for the calculation of entropy and complexity actually measure different properties of the signal. The tested methods, Shannon entropy (ShEn), spectral entropy, approximate entropy (ApEn), Lempel-Ziv complexity (LZC), and Higuchi fractal dimension (HFD) are then applied to the EEG signal recorded during sedation in the intensive care unit (ICU). It is shown that the applied measures behave in a different manner when compared to clinical depth of sedation score--the Ramsay score. ShEn tends to increase while the other tested measures decrease with deepening sedation. ApEn, LZC, and HFD are highly sensitive to the presence of high-frequency components in the EEG signal. 相似文献
7.
Preparation of 4-Vinyl-2(5H)-Furanoid Structural Unit via Organosilicon and - Selenium Intermediates
Seppo I. Pennanen 《合成通讯》2013,43(10):865-871
Two syntheses of the 2(5H)-furanoid structural unit (especially the 3-methyl derivative 1) have been reported from this laboratory.1,2 The unit 1 is found in many naturally occurring compounds (especially sesqui terpenes). The 4-substi tuted d erivatives of 1 also occur frequently i n natural products, e.g. furospongolide3 2. 相似文献
8.
9.
Let −Dω(·,z)D+q be a differential operator in L2(0,∞) whose leading coefficient contains the eigenvalue parameter z. For the case that ω(·,z) has the particular form
10.
Leo Syrjänen Martti Tolvanen Mika Hilvo Ayodeji Olatubosun Alessio Innocenti Andrea Scozzafava Jenni Leppiniemi Barbara Niederhauser Vesa P Hytönen Thomas A Gorr Seppo Parkkila Claudiu T Supuran 《BMC biochemistry》2010,11(1):1-13