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排序方式: 共有868条查询结果,搜索用时 15 毫秒
1.
Dipl.-Ing. Dipl.-Wirt.?Ing. Arne Katzmarzik 《WIRTSCHAFTSINFORMATIK》2011,53(1):21-35
The market for the new provisioning type Software-as-a-Service (SaaS) has reached a significant size and still shows enormous growth rates. By varying size of SaaS products, providers can improve their market position and profits by successfully acting in the tension area of customer acquisition, pricing and costs. We first elaborate differences concerning product differentiation between classic software provisioning models and SaaS. Then, we introduce a micro-economic based decision model to maximize the return of a provider by finding an optimal granularity, i.e. by varying the size of services. This paper makes two contributions in this context: (1) it provides a conceptual foundation for product differentiation within the scope of SaaS and (2) it presents the first implementation of variable reproduction costs for web based software offers. The model is illustrated by a real world case with data from a SaaS provider. 相似文献
2.
SeyedMehrdad Hosseini Alireza Fatehi Tor Arne Johansen Ali Khaki Sedigh 《Journal of Process Control》2012,22(9):1732-1742
This paper provides a systematic method for model bank selection in multi-linear model analysis for nonlinear systems by presenting a new algorithm which incorporates a nonlinearity measure and a modified gap based metric. This algorithm is developed for off-line use, but can be implemented for on-line usage. Initially, the nonlinearity measure analysis based on the higher order statistic (HOS) and the linear cross correlation methods are used for decomposing the total operating space into several regions with linear models. The resulting linear models are then used to construct the primary model bank. In order to avoid unnecessary linear local models in the primary model bank, a gap based metric is introduced and applied in order to merge similar linear local models. In order to illustrate the usefulness of the proposed algorithm, two simulation examples are presented: a pH neutralization plant and a continuous stirred tank reactor (CSTR). 相似文献
3.
Ajay Matta Muhammad Zia Karim Hoda Gerami Bettina Zoe Benigno Ivan Cheng Arne Mehrkens William Mark Erwin 《International journal of molecular sciences》2022,23(10)
Background: Tissue sources of pain emanating from degenerative discs remains incompletely understood. Canine intervertebral discs (IVDs) were needle puncture injured, 4-weeks later injected with either phosphate-buffered saline (PBS) or NTG-101, harvested after an additional fourteen weeks and then histologically evaluated for the expression of NGFr, BDNF, TrkB and CALCRL proteins. Quantification was performed using the HALO automated cell-counting scoring platform. Immunohistochemical analysis was also performed on human IVD tissue samples obtained from spinal surgery. Immunohistochemical analysis and quantification of neurotrophins and neuropeptides was performed using an in vivo canine model of degenerative disc disease and human degenerative disc tissue sections. Discs injected with NTG-101 showed significantly lower levels of Nerve Growth Factor receptor (NGFr/TrkA, p = 0.0001), BDNF (p = 0.009), TrkB (p = 0.002) and CALCRL (p = 0.008) relative to PBS injections. Human IVD tissue obtained from spinal surgery due to painful DDD show robust expression of NGFr, BDNF, TrkB and CALCRL proteins. A single intradiscal injection of NTG-101 significantly inhibits the expression of NGFr, BDNF, TrkB and CALCRL proteins in degenerative canine IVDs. These results strongly suggest that NTG-101 inhibits the development of neurotrophins that are strongly associated with painful degenerative disc disease and may have profound effects upon the management of patients living with discogenic pain. 相似文献
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6.
Richard P. Fischer Arne W. Fliflet 《Journal of Infrared, Millimeter and Terahertz Waves》2002,23(9):1297-1313
This paper presents the design and test of asymmetric quasioptical resonators for gyrotron applications, where most of the diffraction output coupling comes from the smaller of two mirrors. A computer code based on scalar diffraction theory is used to calculate the resonator losses and the electric field near the mirrors. Resonators with mirror separations approaching confocal have reduced side lobes in the diffraction patterns, which should allow for better power transmission and focusing. Cold tests have been performed at 94 and 141 GHz to measure the quality factor of the asymmetric resonators as a function of mirror separation and mirror misalignment. Typical resonator parameters include 65 cm mirror separation, 1-3% output coupling and 85% of the losses from the small mirror. A half-symmetric resonator with one flat and one curved mirror has also been investigated. The calculated values of Q are in reasonably good agreement with the cold test measurements. 相似文献
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Matthias Schulz Frank Balzer Dorothea Scheunemann Oriol Arteaga Arne Lützen Stefan C. J. Meskers Manuela Schiek 《Advanced functional materials》2019,29(16)
A facile route to soft matter self‐powered bulk heterojunction photodiode detectors sensitive to the circular polarization state of light is shown based on the intrinsic excitonic circular dichroism of the photoactive layer blend. As light detecting materials, enantiopure semiconducting small molecular squaraine derivates of opposite handedness are employed. Via Mueller matrix ellipsometry, the circular dichroism is proven to be of H‐type excitonic nature and not originating from mesoscopic structural ordering. Within the green spectral range, the photodiodes convert circular polarized light into a handedness‐dependent photocurrent with a maximum dissymmetry factor of ±0.1 corresponding to 5% overall efficiency for the polarization discrimination under short circuit conditions. On the basis of transfer matrix optical simulations, it is rationalized that the optical dissymmetry fully translates into a photocurrent dissymmetry for ease of device design. Thereby, the photodiode's ability to efficiently distinguish between left and right circularly polarized light without the use of external optical elements and voltage bias is demonstrated. This allows a straightforward and sustainable future design of flexible, lightweight, and compact integrated platforms for chiroptical imaging and sensing. 相似文献
9.
Víctor P. Gil Jiménez Thomas Eriksson Ana García Armada M. Julia Fernández-Getino García Tony Ottosson Arne Svensson 《Wireless Personal Communications》2008,47(1):101-112
In this paper, several algorithms for compressing the feedback of channel quality information are presented and analyzed.
These algorithms are developed for a proposed adaptive modulation scheme for future multi-carrier 4G mobile systems. These
strategies compress the feedback data and, used together with opportunistic scheduling, drastically reduce the feedback data
rate. Thus the adaptive modulation schemes become more suitable and efficient to be implemented in future mobile systems,
increasing data throughput and overall system performance.
相似文献
Arne SvenssonEmail: |
10.
During the past years, research covering propagation, channelcharacterization and wireless systems performance have yield asubstantial knowledge of the 60 GHz channel. The unlicensed 60 GHzfrequency band presents many attractive properties for wirelesscommunications. The environments in which the 60 GHzinfrastructure are to be designed are typically propagation- andcoverage-limited. This paper describes the important factors thatmust be taken into account when designing a wireless local areanetwork (WLAN) architecture operating in this frequency band.Therefore, we motivate the reasons of using distributedtransmitting antennas and multiple receiving antennas (MRA) inorder to mitigate the poor Direction of Arrival (DoA) diversityand to exploit the spatial diversity at the receiver. Such asystem can be considered as a multiple input multiple output(MIMO) system. We investigate the advantages of combining aVirtual Cellular Network (VCN) (using single frequency network anddistributed antennas) and MRA for the downlink. Several ways tocombine the signals with different levels of complexity arepresented. In the most complex case using Singular ValueDecomposition (SVD), it is possible to add coherently thecontribution of each antenna in a virtual cell while retaining thepath diversity inherent to the VCN infrastructure. The schemesyield several advantages: symbol diversity is improved, pathdiversity is still present, antenna gain using multiplebeamformers is increased and the multipath can be reduced. Theconcept is applicable to most types of single frequency networksbut it is especially well appropriate for the 60 GHz VCN/WLANusing orthogonal frequency division multiplexing (OFDM).Simulations give a realistic performance for QPSK, 8-PSK, and16-QAM baseband modulations with a 256-subcarrier OFDM using arate 1/2–convolutional code for a 2 ×2 VCN system.Results show a Eb/N0 improvement of up to 6.2 dB usingthesingular value decomposition method with 16-QAM compared to thesingle input single output (SISO) coded reference. 相似文献