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101.
研究了定义在有限区间(0,l)上的具有一般分离型边条件的不定Sturm—Liouville算子的特征函数的振荡问题.利用Prufer变换,给出了上述Sturm-Liouville算子特征值的符号指标的具体形式;得到了特征值的符号指标与Weyl函数以及Prufer角在该特征值处的罗朗展式(泰勒展式)的首项系数的符号之间的关系;最后,在上述两个结果的基础上给出了上述Sturm—Liouville算子的第n个正特征值所对应的特征函数在[0,l]内的零点个数的计算公式. 相似文献
102.
Zhang Fangguo Wang Changjie Wang Yumin 《电子科学学刊(英文版)》2002,19(4):369-374
E-cash is a type of very important electronic payment systems.The complete anonymity of E-cash can be used for criminal activities,so E-cash should be anonymity controlled.Moreover,Elliptic Curve Cryptography(ECC)has been regard as the mainstream of current public cryptography.In this paper,a new anonymity controlled E-cash scheme based on ECC for the first time and using a new technology-one-time key pairs digital signature is designed,and its security and efficiency are analyzed.In our scheme,the coin tracing ,and owner tracing can be implemented. 相似文献
103.
John P. Robinson 《Journal of Electronic Testing》1992,3(1):9-16
Test data reduction for digital systems is often accomplished through the use of a feedback shift register. This method, known as signature analysis, can exhibit error masking or aliasing. Recent analysis has shown that the use of a primitive polynomial for the register feedback can reduce the probability of aliasing. In this work we demonstrate that not all primitive polynomials are created equal. Some primitive polynomials can have very large transients in their aliasing probability. For example, 1 +X
13 +X
33 can exhibit an aliasing probability more than a million times larger than its asymptotic value of 2–33. An evaluation procedure is presented which can identify polynomials with good transient characteristics. Some recommended feedback polynomials are given. 相似文献
104.
I. P. Litikov 《Journal of Electronic Testing》1991,1(4):301-304
Here we propose a new approach to the testing of digital devices, which can potentially save diagnostic hardware. An example is given for testing combinational devices. Estimates are given for reliability and hardware complexity, and an algorithm for designing operability tests is described. 相似文献
105.
106.
In built-in self-test for logic circuits, test data reduction can be achieved using a linear feedback shift register. The probability that this data reduction will allow a faulty circuit to be declared good is the probability of aliasing. Based on the independent bit-error model, we show that the code spectra for the cyclic code generated by the feedback polynomial can be used to obtain an exact expression for the aliasing probability of a multiple input signature register when the test length is a multiple of the cycle length. Several cases are examined and, as expected, primitive feedback polynomials provide the best performance. Some suggestions to avoid peaks in the aliasing probability are given. 相似文献
107.
Using the constructions of the preceding two papers, we construct a natural transformation (after inverting 2) from the Browder-Novikov-Sullivan-Wall
surgery exact sequence of a compact manifold to a certain exact sequence of C
*-algebra K-theory groups.
Mathematics Subject Classification (1991): 19J25, 19K99 相似文献
108.
We develop the theory of analytically controlled Poincaré complexes over C
*-algebras. We associate a signature in C
*-algebra K-theory to such a complex, and we show that it is invariant under bordism and homotopy.
The authors were supported in part by NSF Grant DMS-0100464. 相似文献
109.
Hasan Amca Ahmet Rizaner Kadri Hacioğlu Ali H. Ulusoy 《Wireless Personal Communications》2006,36(1):45-57
In code division multiple access channels multiuser detection techniques are known to be effective strategies to counter the
presence of multiuser interference towards improving spectral efficiency. Generally, multiuser detectors can provide excellent
performance only when the signature waveforms of all users are precisely known. Hence, the estimation of signature waveforms
is a challenging issue in mobile communication systems. In this paper, we compare the performance of two short training sequence
aided signature waveform estimators. One is maximum likelihood type signature waveform estimator that requires the knowledge
of spreading sequences and short training sequences. The other estimator is recently proposed based on subspace method and
requires the knowledge of training sequences only. Through the simulations, we show the signature waveform estimation performance
of both systems and the effect of the estimation error on the performance of a multiuser detector. The complexity comparisons
of both systems are also given.
We use the term “signature waveform” to refer to the convolution of the channel and the spreading code throughout the paper.
Hasan AMCA was born in 1961 in Nicosia-Cyprus. He graduated from the Higher Technological Institute in Magosa – Cyprus (which is renamed
later as Eastern Mediterranean University). He joined EMU in 1985 after receiving a M.Sc. (Digital Signal Processing) degree
from the University of Essex in England (1985). He took his Ph.D. (Mobile Communications) from the University of Bradford
where he was on a Commonwealth scholarship. He has been teaching in the Electrical and Electronic Engineering Department of
Eastern Mediterranean University since 1993 where he also served as the Vice Chairman from Spring 1998 to Spring 2000. He
has been appointed as the Director of the School of Computing and Technology of the EMU since Spring 2000. His research interests
include Multi User Detection of CDMA signals, Adaptive Equalisation, Multi Carrier Systems, Mobile Radio Systems and Networks,
Internet and Information Technology Applications in Education.
Ahmet Rizaner was born in Larnaca, Cyprus, on January 31, 1974. He received the B.S. and M.S. degrees in Electrical and Electronics Engineering
from the Eastern Mediterranean University, Famagusta, North Cyprus, in 1996 and 1998, respectively. He completed his PhD.
degree in Electrical and Electronic Engineering in Eastern Mediterranean University and joined Eastern Mediterranean University
as a lecturer in 2004. He is lecturing in the School of Computing and Technology. His main research interests include CDMA
communications, adaptive channel estimation, and multiuser detection technique.
Kadri Hacioğlu was born in Nicosia, Cyprus. He received the B.Sc., M.Sc., and Ph.D. degrees in electrical and electronic engineering from
the Middle East Technical University, Ankara, Turkey, in 1980, 1984, and 1990, respectively. After his two-year military service,
in 1992, he joined the faculty of Eastern Mediterranean University, Magosa, North Cyprus, as an Assistant Professor, and became
an Associate Professor in 1997. While there, he taught several classes on electronics, digital communications, speech processing
and neural networks. During this time, he conducted research on applying fuzzy logic, neural networks, and genetic algorithms
to signal processing and communications problems. From 1998 to 2000, he was a Visiting Professor in the Department of Computer
Science, University of Colorado, Boulder. Here, he taught classes on neural networks and continued his research. Since 2000,
he has been a Research Associate at the Center for Spoken Language Research, University of Colorado. He has authored or coauthored
numerous papers and supervised a dozen M.Sc./Ph.D. theses. His current research interests are concept-based language modeling,
speech understanding, natural language generation, and search methods in speech recognition/understanding. He also does research
on multiuser detection and equalization in CDMA systems.
Ali Hakan Ulusoy was born in Eskişehir, Turkey, on June 3, 1974. He graduated from the double major program of the department of Electrical
and Electronic Engineering and department of Physics in Eastern Mediterranean University as the first rank student of Faculty
of Engineering in 1996. He received his M.S. degree in Electrical and Electronic Engineering in Eastern Mediterranean University
in 1998. He completed his Ph.D. degree in Electrical and Electronic Engineering in Eastern Mediterranean University and joined
Eastern Mediterranean University as a lecturer in 2004. He is lecturing in the School of Computing and Technology. His current
research interests include receiver design, multi-user detection techniques, blind and trained channel estimation in Code
Division Multiple Access (CDMA). 相似文献
110.
We apply the theory of signature invariants of links in rational homology spheres to covering links of homology boundary links. From patterns and Seifert matrices of homology boundary links, we derive an explicit formula to compute signature invariants of their covering links. Using the formula, we produce fused boundary links that are positive mutants of ribbon links but are not concordant to boundary links. We also show that for any finite collection of patterns, there are homology boundary links that are not concordant to any homology boundary links admitting a pattern in the collection.