A dynamic spectrum access scheme for cognitive radio networks

Abstract—In this paper, the dynamic spectrum access problem for cognitive radio (CR) networks is formulated as maximizing the sum channel capacity while satisfying the power budgets of individual secondary user radios as well as the SINR constraints on both the secondary and primary users. By applying the Karush-Kuhn-Tucker theorem, we derive a waterfilling soluton. An iterative water-filling algorithm is proposed for implementing joint channel and power allocation in a dynamically changing set of available channels. The proposed algorithm has a complexity that increases linearly with both the number of channels and the number of users

An extensible product structure model for product lifecycle management in the make-to-order environment

This paper presents a product structure model with a semantic representation technique that make the product structure extensible for developing product lifecycle management (PLM) systems that is flexible for make-to-order environment. In the make-to-order business context, each product could have a number of variants with slightly different constitutions to fulfill different customer requirements. All the variants of a family have common characteristics and each variant has its specific features. A master-variant pattern is proposed for building the product structure model to explicitly represent common characteristics and specific features of individual variants. The model is capable of enforcing the consistency of a family structure and its variant structure, supporting multiple product views, and facilitating the business processes. A semantic representation technique is developed that enables entity attributes to be defined and entities to be categorized in a neutral and semantic format. As a result, entity attributes and entity categorization can be redefined easily with its configurable capability for different requirements of the PLM systems. An XML-based language is developed for semantically representing entities and entity categories. A prototype as a proof-of-concept system is presented to illustrate the capability of the proposed extensible product structure model

Curcumin Promoted the Apoptosis of Cisplain-resistant Human Lung Carcinoma Cells A549/DDP through Down-regulating miR-186*

Background and objective Curcumin, a natural compound, is derived from the rthizom of Curcuma longa. In vitro and in vivo preclinical studies have shown its anti-inflammatory, antioxidant, anticancer activities and so on. miR-186*, which was found by microarray technology, was highly expressed in lung carcinoma cells A549/DDP. The aim of this study is to illustrate whether Curcumin could promote the apoptosis of A549/DDP cells through regulating the expression of miR-186*. Methods An oligonucleotide microarray chip was used to profile microRNA (miRNA) expressions in A549/DDP cells treated with and without Curcumin. The significantly differentially expressed miRNA, which was selected from microarray chip, validated by quantitative real-time PCR. Ultimately, the remarkably expressed miRNA modulated the apoptosis assaying by flow cytometry expriments and the survival rate was measured by MTT method. Results The microarray chip results demonstrated: Curcumin altered the expression level of miRNAs compared with untreated control in A549/DDP cell line, miR-186* was significantly down-regulated after Curcumin treatment, which confirmed by quantitative real-time PCR. Downregulation of miR-186* expression by curcumin elevated the apoptosis, and the survival rate of A549/DDP cells decreased; but up-regulation of miR-186* expression by transfection its mimics restrained the apoptosis, the survival rate of A549/DDP cells increased, which were assayed by flow cytometry expriments and MTT method. Conclusion Modulation of miRNAs expression may be an important mechanism underlying the biological roles of Curcumin

Revealing the Political Decision Toward Chinese Carbon Abatement: Based on Equity and Efficiency Criteria

China\u27s economic reform over the past 30 years has allowed the free market to drive economic development. However, government still plays a key role in the energy sector by allocating energy conservation and emissions abatement. How does the government make an equity decision as a tradeoff to market efficiency? This is an unanswered question. The purpose of this paper is to illustrate the government\u27s preference toward equity and efficiency. Using the provincial level CO2 intensity allocation data, we investigate the political decision that the government made based on the equity and efficiency criteria. We find that the equity index plays a more important role than the efficiency index in determining the CO2 intensity target. In addition, political factors such as social stability are found to be important factors

Regional allocation of carbon dioxide abatement in China

https://doi.org/10.1016/j.chieco.2011.06.00

Characterization of Wave Propagation in Thin Laminated Plates

This is an electronic version of an article published in Du, C., Ni, Q. & Natsuki, T. (2010). Characterization of Wave Propagation in Thin Laminated Plates. [Materials and Manufacturing Processes is available online at: http://www.informaworld.com/smpp/content~db=all?content=10.1080/10426910903426349The formulae including the in-plane stiffness and bending stiffness coefficients and coupling effect in out-plane were presented for analyzing characterization of wave propagation. Using the present formulae, the wave velocities can be calculated in any case of laminated plates including nonsymmetric lamination. In this study, the characteristics of wave propagation in thin laminated plates were investigated in detail. Five modes including symmetric modes and antisymmetric modes were obtained from the proposed formulae. For each mode, the wave velocities of laminated plates were investigated in different conditions such as plate thickness, stacking sequence, and vibrational frequency.ArticleMATERIALS AND MANUFACTURING PROCESSES. 25(4):259-263 (2010)journal articl

Planetary gearbox fault diagnosis based on pseudo-fault signal assisted EMD

Pseudo-fault signal assisted empirical mode decomposition (PFS-EMD) is put forward for fault detection and isolation, which is built upon EMD, envelope analysis and pseudo-fault signal. And this method has been proved that it is usable in fault diagnosis of simple gear pair. However, this method is still need further study that whether it can be used for fault diagnosis of complex gearbox. Moreover, planetary gearbox fault diagnosis is much more complicated than fixed-axis gearbox. This paper makes a further study of PFS-EMD and focuses on its application. Combining with the seeded failure experimental data of planetary gearbox, this paper show that PFS-EMD can enhance fault information and weaken other useless information in complex gearbox fault diagnosis