Energy-Delay Tradeoffs of Virtual Base Stations With a Computational-Resource-Aware Energy Consumption Model

The next generation (5G) cellular network faces the challenges of efficiency, flexibility, and sustainability to support data traffic in the mobile Internet era. To tackle these challenges, cloud-based cellular architectures have been proposed where virtual base stations (VBSs) play a key role. VBSs bring further energy savings but also demands a new energy consumption model as well as the optimization of computational resources. This paper studies the energy-delay tradeoffs of VBSs with delay tolerant traffic. We propose a computational-resource-aware energy consumption model to capture the total energy consumption of a VBS and reflect the dynamic allocation of computational resources including the number of CPU cores and the CPU speed. Based on the model, we analyze the energy-delay tradeoffs of a VBS considering BS sleeping and state switching cost to minimize the weighted sum of power consumption and average delay. We derive the explicit form of the optimal data transmission rate and find the condition under which the energy optimal rate exists and is unique. Opportunities to reduce the average delay and achieve energy savings simultaneously are observed. We further propose an efficient algorithm to jointly optimize the data rate and the number of CPU cores. Numerical results validate our theoretical analyses and under a typical simulation setting we find more than 60% energy savings can be achieved by VBSs compared with conventional base stations under the EARTH model, which demonstrates the great potential of VBSs in 5G cellular systems.Comment: 5 pages, 3 figures, accepted by ICCS'1

Beamformer Based on Quaternion Processes

In this chapter, the problem of quaternion beamformer based on linear and widely linear hypercomplex processing is investigated in scenarios, where there exist one signal and one interference that are uncorrelated. First, we introduce brief information about the quaternion algebra and a quaternion model of linear symmetric array with two-component electromagnetic (EM) vector-sensors is presented. Based on array’s quaternion model, a quaternion MVDR (QMVDR) beamformer is derived and its performance is analysed. Second, we propose the general expression of a quaternion semi-widely linear (QSWL) beamformer and derive its useful implementation and the array’s gain expression. Finally, we give the main results of Monte Carlo simulation

Expression and cellular localization of cyclooxygenases and prostaglandin E synthases in the hemorrhagic brain

<p>Abstract</p> <p>Background</p> <p>Although cyclooxygenases (COX) and prostaglandin E synthases (PGES) have been implicated in ischemic stroke injury, little is known about their role in intracerebral hemorrhage (ICH)-induced brain damage. This study examines the expression and cellular localization of COX-1, COX-2, microsomal PGES-1 (mPGES-1), mPGES-2, and cytosolic PGES (cPGES) in mice that have undergone hemorrhagic brain injury.</p> <p>Methods</p> <p>ICH was induced in C57BL/6 mice by intrastriatal injection of collagenase. Expression and cellular localization of COX-1, COX-2, mPGES-1, mPGES-2, and cPGES were examined by immunofluorescence staining.</p> <p>Results</p> <p>In the hemorrhagic brain, COX-1, mPGES-2, and cPGES were expressed constitutively in neurons; COX-1 was also constitutively expressed in microglia. The immunoreactivity of COX-2 was increased in neurons and astrocytes surrounding blood vessels at 5 h and then tended to decrease in neurons and increase in astrocytes at 1 day. At 3 days after ICH, COX-2 was observed primarily in astrocytes but was absent in neurons. Interestingly, the immunoreactivity of mPGES-1 was increased in neurons in the ipsilateral cortex and astrocytes in the ipsilateral striatum at 1 day post-ICH; the immunoreactivity of astrocytic mPGES-1 further increased at 3 days.</p> <p>Conclusion</p> <p>Our data suggest that microglial COX-1, neuronal COX-2, and astrocytic COX-2 and mPGES-1 may work sequentially to affect ICH outcomes. These findings have implications for efforts to develop anti-inflammatory strategies that target COX/PGES pathways to reduce ICH-induced secondary brain damage.</p

Marine propulsion shaft system fault diagnosis method based on partly ensemble empirical mode decomposition and SVM

This paper investigates the application of the Partly Ensemble Empirical Mode Decomposition (PEEMD), Principal Component Analysis (PCA) and Support Vector Machine (SVM) on signal processing, attribute reduction and pattern recognition. On this basis, a novel method for mechanical faulty diagnosis based on PEEMD, PCA and SVM is presented, which utilizes the PEEMD to extract faulty feature parameters from the statistical characteristics of intrinsic mode functions to constitute feature vectors, and then makes the attribute reduction by PCA method to obtain the key features, lastly these key features are input into GA-optimized SVM to accomplish faulty pattern recognition. The experimental results of the proposed method to fault diagnosis of the rolling bearing and stern bearing on marine propulsion shaft system show that this method can extract the faulty features, which have better classification ability and at the same time reduce the computation complexity significantly, accordingly improve the classifier efficiency and achieve a better classification performance

Research on electron and positron spectrum in the high-energy region based on the gluon condensation model

Electron(positron), proton and nuclei can be accelerated to very high energy by local supernova remnants (SNR). The famous excesses of electron and proton (nuclei) potentially come from such kind of local sources. Recently, the DAMPE experiment measured the electron spectrum (including both electrons and positrons) of cosmic rays with high-accuracy. It provides an opportunity to further explore the excess of electrons. According to the gluon condensation (GC) theory, once GC occurs, huge number of gluons condense at a critical momentum, and the production spectrum of electron and proton showing typical GC characteristics. There are exact correlations between the electron and proton spectrum from a same GC process. It is possible to interpret the power-law break of cosmic rays in view of GC phenomenon, and predict one from another based on the relations between electron and proton spectrum. In this work, we point out the potential existence of a second excess in the electron spectrum, the characteristics of this excess is derived from experimental data of proton. We hope that the future DAMPE experiments will confirm the existence of this second excess and support the result of GC model

Effect of 3,3′-Biisofraxidin on Apoptosis of Human Gastric Cancer BGC-823 Cells

Purpose: To study the effect of 3,3′-biisofraxidin from Sarcandrae Herba on the proliferation of BGC- 823 cells and the possible mechanisms.Methods: Cell Counting Kit-8 (CCK-8), flow cytometry, Western blot and xenograft assays were used to determine the effects of 3,3′-biisofraxidin on the proliferation, apoptosis, apoptotic proteins and xenograft of BGC-823 cells.Results: 3,3′-Biisofraxidin significantly (p &lt; 0.01) inhibited the proliferation of BGC-823 cells (concentrations: 10 - 40 μM; cell viability: 30.45 - 76.68 % in CCK-8 assay) with half maximal inhibitory concentration (IC50) value of 20.35 μM and induced the apoptosis of BGC-823 cells (concentrations: 10, 20 and 40 μM; apoptotic cells: 11.92, 20.10 and 33.64 % in flow cytometry assay), compared with the control (cell viability: 99.73 %; apoptotic cells: 5.18 %). 3,3′-Biisofraxidin (10, 20 and 40 μM in vitro; 40 mg/kg in vivo) significantly (p &lt; 0.05 or 0.01) down-regulated the expressions of anti-apoptotic proteins (Bcl-2, Bcl-xl and Survivin) and up-regulated the expressions of pro-apoptotic proteins (Smac, caspase-3, caspase-7 and caspase-9), compared with the control. Moreover, the release of cytochrome c from the mitochondria to the cytoplasm was significantly (p &lt; 0.01) promoted in vitro, compared with the control. 3,3′-Biisofraxidin (40 mg/kg) significantly (p &lt; 0.05 or 0.01) inhibited the growth of tumor in xenograft assay, compared with the control.Conclusion: 3,3′-Biisofraxidin significantly induces the apoptosis of BGC-823 cells in vitro and in vivo through the mitochondria-mediated apoptotic pathway, and therefore has a potential to be developed into an anti-gastric cancer drug.Keywords: Sarcandrae Herba, Gastric cancer, 3,3′-Biisofraxidin, Mitochondria-mediated apoptotsis, Cell Counting Kit-8, Xenograf

Environmental economic impact assessment in China: Problems and prospects

The use of economic valuation methods to assess environmental impacts of projects and policies has grown considerably in recent years. However, environmental valuation appears to have developed independently of regulations and practice of environmental impact assessment (EIA), despite its potential benefits to the EIA process. Environmental valuation may be useful in judging significance of impacts, determining mitigation level, comparing alternatives and generally enabling a more objective analysis of tradeoffs. In China, laws and regulations require the use of environmental valuation in EIA, but current practice lags far behind. This paper assesses the problems and prospects of introducing environmental valuation into the EIA process in China. We conduct four case studies of environmental economic impact assessment (EEIA), three of which are based on environmental impact statements of construction projects (a power plant, a wastewater treatment plant and a road construction project) and one for a regional pollution problem (wastewater irrigation). The paper demonstrates the potential usefulness of environmental valuation but also discusses several challenges to the introduction and wider use of EEIA, many of which are likely to be of relevance far beyond the Chinese context. The paper closes with suggesting some initial core elements of an EEIA guidelineEnvironmental impact assessment; Environmental valuation; China; Economic analysis