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61.
62.
Topology and weights are closely related in weighted complex networks and this is reflected in their modular structure. We present a simple network model where the weights are generated dynamically and they shape the developing topology. By tuning a model parameter governing the importance of weights, the resulting networks undergo a gradual structural transition from a module-free topology to one with communities. The model also reproduces many features of large social networks, including the "weak links" property. 相似文献
63.
64.
This paper validates the feasibility of automated optimization of key wideband code division multiple access (WCDMA) radio resource management parameters using control methods. The parameters are regularly adjusted in order to improve performance. The parameters examined in this study include the total cell transmission power target, the received total interference target, the downlink radio link power maximums, the handover windows and the pilot channel powers. The control was based on expert‐defined rules, which applied specific trade‐off policies and statistics of poor quality calls, blocking, packet queuing, power and interference levels and terminal measurements to qualify the parameter values. The approach was validated using a dynamic WCDMA system simulator with a deployment of macro and micro cells on a city region. Results on automated optimization of single parameters on cell level and results on simultaneous multi‐parameter optimization on cell‐cluster level are presented in this paper. The use of the automated parameter optimization methods was shown to result in a significant increase of capacity in comparison to the default parameter settings. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
65.
棉铃虫(Heliothisarmigera)血淋巴对人的A、B、O型红细胞有同等的凝集活性,对兔、小白鼠、豚鼠、蟾蜍、鲫鱼、鸡红细胞有不同的凝集活性,对山羊红细胞无凝集活性.其凝集活性能被D-半乳糖明显地抑制.对Ca2+无依赖性.70℃处理15min凝集活性趋于零.棉铃虫核型多角体病毒的诱导使其活性明显增加.化蛹早期及蛹期凝集活性下降.血淋巴凝集素通过盐析、凝胶过滤和纤维素层析得到分离.它在SDS-PAGE中表现为单一带,为糖蛋白,分子量为7.08×104.其蛋白质含量为98.74%,糖含量为1.26%. 相似文献
66.
We provide a complete extension of Minimal Walking Technicolor able to account for the Standard Model fermion masses. The model is supersymmetric at energies greater or equal to the technicolor compositeness scale. We integrate out, at the supersymmetry breaking scale, the elementary Higgses. We use the resulting four-fermion operators to derive the low energy effective theory. We then determine the associated tree-level vacuum and low energy spectrum properties. Furthermore we investigate the phenomenological viability of the model by comparing its predictions with electroweak precision tests and experimental bounds on the mass spectrum. We then turn to the composite Higgs phenomenology at the LHC and show that current data are already constraining the parameter space of the model. 相似文献
67.
This paper presents continuous learning methods in a monopoly pricing problem where the firm has uncertainty about the buyers’
preferences. The firm designs a menu of quality-price bundles and adjusts them using only local information about the buyers’
preferences. The learning methods define different paths, and we compare how much profit the firm makes on these paths, how
long it takes to learn the optimal tariff, and how the buyers’ utilities change during the learning period. We also present
a way to compute the optimal path in terms of discounted profit with dynamic programming and complete information. Numerical
examples show that the optimal path may involve jumps where the buyer types switch from one bundle to another, and this is
a property which is difficult to include in the learning methods. The learning methods have, however, the benefit that they
can be generalized to pricing problems with many buyers types and qualities. 相似文献
68.
Matti Antola Stefano Di Chiara Francesco Sannino Kimmo Tuominen 《The European Physical Journal C - Particles and Fields》2011,71(11):1784
We introduce novel extensions of the Standard Model featuring a supersymmetric technicolor sector. First we consider N=4\mathcal{N}=4 Super Yang–Mills which breaks to N=1\mathcal{N}=1 via the electroweak (EW) interactions and coupling to the MSSM. This is a well defined, economical and calculable extension
of the SM involving the smallest number of fields. It constitutes an explicit example of a natural supersymmetric conformal
extension of the Standard Model featuring a well defined connection to string theory. It allows us to interpolate, depending
on how we break the underlying supersymmetry, between unparticle physics and Minimal Walking Technicolor. As a second alternative
we consider other N = 1\mathcal{N} =1 extensions of the Minimal Walking Technicolor model. The new models allow all the standard model matter fields to acquire
a mass. 相似文献
69.
Tero Kangas Timo D. H?m?l?inen Kimmo Kuusilinna 《The Journal of VLSI Signal Processing》2006,44(1-2):79-95
Evolving video coding standards demand functional flexibility for implementations, not only at design time but also after
fabrication. This paper presents a System-on-Chip design approach with a feasible combination of performance, scalability,
programmability, area efficiency, and design time effort for a video encoder. The encoder is based on a homogeneous master-slave
processor architecture. Each slave encodes a part of the frame in the Single Program Multiple Data (SPMD) data parallel model.
Both shared and distributed memory architectures are presented. Design effort is reduced by identical program codes, automated
assembly of software and hardware modules independent of the number and type of processors, as well as our flexible on-chip
communication network called Heterogeneous IP Block Interconnection (HIBI). A case study implementation with two to ten simple
ARM7 processors, 32-bit HIBI bus and non-optimized processor-independent software gives the performance from 6 to 53 fps for
QCIF. The whole encoder area ranges from 173 to 770 kgates excluding the memories. The relation scales reasonably well to
systems with more powerful processors and optimized code. The optimization of the communication network shows that with more
than six slaves even a serial HIBI connection with 100 MHz speed is feasible. HIBI and the parallelization approach allow
exploration and optimization of the communication both at the application and architecture layers.
Tero Kangas, MSc ’01, Tampere University of Technology (TUT). Since 1999 he has been working as a research scientist in the Institute
of Digital and Computer Systems (DCS) at TUT. Currently he is working towards his PhD degree and his main research topics
are system architectures and SoC design methodologies in multimedia applications.
Kimmo Kuusilinna, PhD ’01, TUT. His main research interests include system-level design and verification, interconnection networks, and parallel
memories. Currently he is working as a senior research engineer at the Nokia Research Center.
Timo D. H?m?l?inen, MSc ’93, PhD ’97, TUT. He acted as a senior research scientist and project manager at TUT in 1997-2001. He was nominated
to full professor at TUT/Institute of Digital and Computer Systems in 2001. He heads the DACI research group that focuses
on three main lines: wireless local area networking and wireless sensor networks, high-performance DSP/HW based video encoding,
and interconnection networks with design flow tools for heterogeneous SoC platforms. 相似文献
70.
Antti?Laakso Mihail?Dumitrescu Jukka?Viheri?l? Jarkko?Telkk?l? Juha?Tommila Kimmo?Haring Tomi?Leinonen Sanna?Ranta Markus?Pessa 《Optical and Quantum Electronics》2009,41(1):11-16
The paper presents a simulation-based analysis of laterally-corrugated ridge-waveguide distributed feedback semiconductor
lasers emitting at 980 nm. The simulations were performed using software developed in-house and the PICS3D software package
from Crosslight Software Inc. The effects of the corrugation geometry, phase-shift section, and mirror reflectivities on single
longitudinal mode operation are discussed. The lasers, designed along the guidelines derived from the simulation results,
were fabricated by using molecular beam epitaxy for wafer growth and low-cost nano-imprint lithography. They exhibited stable
single-mode operation with up to 50 dB side-mode suppression ratio. 相似文献