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Frame-bent structure is usually used in the power plants, and in many cases the bent part of it is usually simplified as an articulated bar. To prove the rationality of this simplification, in this paper, two models of one frame-bent structure are built and let them experience earthquake waves from different directions by the mode-superposition response spectrum way, then the shear that each column bears can be calculated .Through the data we get ,the judgment about the rationality of the simplification way can be made

By adjusting the strength of IPRs protection, the government can change the extent of knowledge spillovers in R&D. A large spillover rate helps to improve the productivity of the less efficient firms and save on the overall production costs. But, at the same time, it reduces the innovator's incentives to conduct R&D and results in a lower equilibrium innovation level. So, there is an inherent tension between knowledge diffusion and technological progress. In this paper, we formalized this relationship in a two stage asymmetric duopoly model and discussed the optimal IPRs protection policy. The main conclusion is that, to maximize social welfare the strength of IPRs protection should rise as the increase of the innovating firm's R&D efficiency.

Portfolio selection with higher moments is a NP-hard nonconvex polynomial optimization problem. In this paper, we propose an efficient local optimization approach based on DC (Difference of Convex functions) programming—called DCA (DC Algorithm)—that consists of solving the nonconvex program by a sequence of convex ones. DCA will construct, in each iteration, a suitable convex quadratic subproblem which can be easily solved by explicit method, due to the proposed special DC decomposition. Computational results show that DCA almost always converges to global optimal solutions while comparing with the global optimization methods (Gloptipoly, Branch-and-Bound) and it outperforms several standard local optimization algorithms.

Cochlear implant has been successfully applied in clinic. Recent research indicates vision implants may be the potential way to restore sight for the blind. Here, principle and common structure of vision implants are introduced. Main vision approaches of retinal, optic nerve, and cortical prosthesis are reviewed. In our progress, electrical response at visual cortex is recorded, when penetrating electrodes stimulate rabbit optic nerve, vision implants based on optic nerve stimulator chip (ONSC) and Chipcon radio frequency (RF) chip are under developing. Despite several obstacles to overcome, promising results in animal and human experiments give scientists confidence that artificial vision implants will bring light to the blind in the near future.

Osteoarthritis (OA) is a common cause of functional deterioration in older adults, and altered chondrogenesis is the most common pathophysiological process involved in the development of OA. MicroRNA‑145 (miR‑145) has been shown to regulate chondrocyte homeostasis. However, the function of miR‑145 in OA remains to be elucidated. In the present study, the expression levels of miR‑145 were examined in cartilage specimens from 25 patients with knee OA using reverse transcription‑quantitative polymerase chain reaction analysis. The effects of miR‑145 on the proliferation and fibrosis of the C‑20/A4 and CH8 cell lines were also investigated using 3-(4,5-dimethylth-iazol-2-yl)-2,5-diphenyltetrazolium bromide and western blot assays in vitro. The results revealed that the expression of miR-145 was decreased in the OA cartilage tissues, compared with normal cartilage tissues. The overexpression of miR‑145 by transfection of cells with miR‑145 mimics significantly inhibited C‑20/A4 and CH8 cell proliferation and fibrosis. Furthermore, tumor necrosis factor receptor superfamily, member 11b (TNFRSF11B) was identified as a direct target of miR‑145 in chondrocytes, which was confirmed using a dual‑luciferase reporter assay. The expression level of TNFRSF11B was markedly upregulated in the patients with OA, and the ectopic expression of miR‑145 was capable of suppressing the expression of TNFRSF11B. In addition, the knock down of TNFRSF11B using specific small interfering RNA also inhibited the proliferation and fibrosis of C‑20/A4 and CH8 cells in vitro. These data provide the first evidence, to the best of our knowledge, to suggest the critical function of miR‑145 in regulating the expression of TNFRSF11B, which may have important implications on the regulation of chondrocyte proliferation and fibrosis in OA.

Cooperative binding mechanisms are a common feature in biology, enabling a diverse range of protein-based molecular machines to regulate activities ranging from oxygen uptake to cellular membrane transport. Much, however, is not known about such cooperative binding mechanisms, including how such events typically add to the overall stability of such protein systems. Measurements of such cooperative stabilization events are challenging, as they require the separation and resolution of individual protein complex bound states within a mixture of potential stoichiometries to individually assess protein stabilities. Here, we report ion mobility-mass spectrometry results for the concanavalin A tetramer bound to a range of polysaccharide ligands. We use collision induced unfolding, a relatively new methodology that functions as a gas-phase analog of calorimetry experiments in solution, to individually assess the stabilities of concanavalin A bound states. By comparing the differences in activation voltage required to unfold different concanavalin A–ligand stoichiometries, we find evidence suggesting a cooperative stabilization of concanavalin A occurs upon binding most carbohydrate ligands. We critically evaluate this observation by assessing a broad range of ligands, evaluating the unfolding properties of multiple protein charge states, and by comparing our gas-phase results with those obtained from calorimetry experiments carried out in solution.

The development of cost-effective and applicable strategies for producing efficient oxygen evolution reaction (OER) electrocatalysts is crucial to advance electrochemical water splitting. Herein, a kinetically controlled room-temperature coprecipitation is developed as a general strategy to produce a variety of sandwich-type metal hydroxide/graphene composites. Specifically, well-defined α-phase nickel cobalt hydroxide nanosheets are vertically assembled on the entire graphene surface (NiCo-HS@G) to provide plenty of accessible active sites and enable facile gas escaping. The tight contact between NiCo-HS and graphene promises effective electron transfer and remarkable durability. It is discovered that Ni doping adjusts the nanosheet morphology to augment active sites and effectively modulates the electronic structure of Co center to favor the adsorption of oxygen species. Consequently, NiCo-HS@G exhibits superior electrocatalytic activity and durability for OER with a very low overpotential of 259 mV at 10 mA cm−2. Furthermore, a practical water electrolyzer demonstrates a small cell voltage of 1.51 V to stably achieve the current density of 10 mA cm−2, and 1.68 V to 50 mA cm−2. Such superior electrocatalytic performance indicates that this facile and manageable strategy with low energy consumption may open up opportunities for the cost-effective mass production of various metal hydroxides/graphene nanocomposites with desirable morphology and competing performance for diverse applications.

Developing highly efficient low‐cost electrocatalysts for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline electrolyte is essential to advance water electrolysis technology. Herein, Ni(OH)2 nanoplates aligned on NiAl foil (Ni(OH)2/NiAl) are developed by simply dealloying NiAl foil in KOH, which exhibits high electrocatalytic activity for OER with a small overpotential of 289 mV to achieve 10 mA cm−2 and outstanding durability with no detectable degradation during long‐term operation. Furthermore, such Ni(OH)2/NiAl can effectively act as an active and robust hierarchical scaffold to simply electrodeposit other catalysts with intrinsically higher activity such as NiMo and NiFe nanoparticles for highly efficient HER and OER, respectively. The prepared NiFe/Ni(OH)2/NiAl displays superior OER catalytic activity with overpotentials of 246, 315, and 374 mV at 10, 100, and 500 mA cm−2, respectively. While NiMo/Ni(OH)2/NiAl catalyst exhibits remarkable HER performance with a small overpotential of 78 mV to deliver 10 mA cm−2. Consequently, the electrolysis device composed of the above two electrocatalysts demonstrates superb water splitting performance with a cell voltage of 1.59 V at 10 mA cm−2. These results open up opportunities to explore and optimize low‐cost advanced catalysts for energy applications.

We propose some new DC (difference of convex functions) programming approaches for solving the Bilinear Matrix Inequality (BMI) Feasibility Problems and the Quadratic Matrix Inequality (QMI) Feasibility Problems. They are both important NP-hard problems in the field of robust control and system theory. The inherent difficulty lies in the nonconvex set of feasible solutions. In this paper, we will firstly reformulate these problems as a DC program (minimization of a concave function over a convex set). Then efficient approaches based on the DC Algorithm (DCA) are proposed for the numerical solution. A semidefinite program (SDP) is required to be solved during each iteration of our algorithm. Moreover, a hybrid method combining DCA with an adaptive Branch and Bound is established for guaranteeing the feasibility of the BMI and QMI. A concept of partial solution of SDP via DCA is proposed to improve the convergence of our algorithm when handling more large-scale cases. Numerical simulations of the proposed approaches and comparison with PENBMI are also reported.

Detailed chemistry tabulations built from canonical combustion problems, such as premixed or diffusion flamelets, have been the subject of multiple studies. Chemical look-up table construction strategies may rely on the definition of progress variables, which are usually obtained from combination of reactants and final products mass fractions. Finding a progress variable such that all relevant species can be retrieved from knowledge of it is not always straightforward; especially for fuel mixtures composed of more than a single hydrocarbon, or for simpler fuels but under conditions where the global reaction progress is not continuous, as in the case of cool-flame ignition. To overcome these difficulties, automated methods are discussed for defining progress by variables in which all species of a chemical scheme, even minor ones, are involved. This is done by formulating constraints applied to progress variable definition: they should evolve in a monotonic manner from fresh to burnt gases and the species derivative in progress variable space should stay moderate for tabulation accuracy. This set of constraints is discretized along chemical trajectories observed in laminar canonical flames, to be formulated in terms of an ensemble of inequalities, which are solved using optimization tools. The outcome is a set of weighting coefficients to be applied to every species of the detailed chemical scheme, in order to construct the progress -variable space. The methods are successfully applied to methane and kerosene premixed flamelets and to n-heptane self-ignition, under conditions with cool-flame effects.

In this paper we did some comparisons between YY0505-2005 and IEC 60601-1-2 edition2.1, and concluded that they are identical in respects of testing items and methods, but significantly different in respects of classification, essential performance and risk analysis. Some suggestions about the transformation and implementation of edition 2.1 standards in our country were proposed.

This article describes the measure to decrease the emission of a domestic infusion pump which can't pass the radiated emission test when performing EMC tests. Then optimizes the measure and evaluates whether these measures affect the original electrical safety of the pump.

The main objective of this thesis focuses on theoretical and algorithmic researches of local and global optimization techniques to DC programming & DCA with Branch and Bound (B&B) and the DC/SDP relaxation techniques to solve several types of non-convex optimization problems (including Combinatorial Optimization and Polynomial Optimization). This thesis is divided into four parts :We present in the first part some fondamental theorems and essential techniques in DC programming & DC Algorithm (DCA), the SDP Relaxation techniques, as well as the Branch and Bound methods (B&B).In the second part, we are interested in solving mixed integer quadratic and linear programs. We propose new local and global approaches based on DCA, B&B and SDP. The implementation of software and numerical simulations have also been investigated.The third part explores the DC programming approaches & DCA combined with a B&B technique and SDP for locally and globally solving a class of polynomial programming. The polynomial program with homogeneous polynomial functionsand its application to portfolio selection problem involving higher order moments in financial optimization have been deeply studied in this part.Finally, in the last part, we present our research on optimization problems under constraints of semi-definite matrices via our DC programming approaches. This part is dedicated to the resolution of the BMI and QMI feasibility problems in the field of optimal control.All these proposed methods have been implemented with MATLAB, C++ etc., that allowing us to confirm the practical use and enrich our research works., L’objectif de cette thèse porte sur des recherches théoriques et algorithmiques d’optimisation locale et globale via les techniques de programmation DC & DCA, Séparation et Evaluation (SE) ainsi que les techniques de relaxation DC/SDP, pour résoudre plusieurs types de problèmes d’optimisation non convexe (notamment en Optimisation Combinatoire et Optimisation Polynomiale). La thèse comporte quatre parties :La première partie présente les outils fondamentaux et les techniques essentielles en programmation DC & l’Algorithme DC (DCA), ainsi que les techniques de relaxation SDP, et les méthodes de séparation et évaluation (SE).Dans la deuxième partie, nous nous intéressons à la résolution de problèmes de programmation quadratique et linéaire mixte en variables entières. Nous proposons de nouvelles approches locales et globales basées sur DCA, SE et SDP. L’implémentation de logiciel et des simulations numériques sont aussi étudiées.La troisième partie explore des approches de la programmation DC & DCA en les combinant aux techniques SE et SDP pour la résolution locale et globale de programmes polynomiaux. Le programme polynomial avec des fonctions polynomiales homogènes et son application à la gestion de portefeuille avec moments d’ordre supérieur en optimisation financière ont été discutés de manière approfondie dans cette partie.Enfin, nous étudions dans la dernière partie un programme d’optimisation sous contraintes de type matrices semi-définies via nos approches de la programmation DC. Nous nous consacrons à la résolution du problème de réalisabilité des contraintes BMI et QMI en contrôle optimal.L’ensemble de ces travaux a été implémenté avec MATLAB, C/C++ ... nous permettant de confirmer l’utilisation pratique et d’enrichir nos travaux de recherche.

Molecular dynamics simulations have been performed on 1-ethyl-2,3-dimethyl-imidazolium hexafluorophosphate (EMMIPF(6)) ionic liquids (ILs) doped with different molar ratios of LiPF(6) at 523.15 K and 1 bar. Ionic conductivity, self-diffusion coefficients, density, and viscosity predicted by MD simulations were found to be in good agreement with previous studies. Structural analysis shows that the Li(+) cation is strongly coordinated by the F atom of the PF(6)(-) anion, and the number of F atoms coordinated with a Li(+) cation in the first solvation shell is about six for all molar ratios of LiPF(6)/EMMIPF(6) 0.05, 0.15, 0.30, and 0.50. The coordination number of the PF(6)(-) anion within the first solvation shell of Li(+) cation is about four, which tends to increase slightly when the salt concentration is increased. The two-dimensional radial-angular distribution study shows that the Li(+)-PF(6)(-) complex tends to form the C(2v) conformation at low salt concentration, whereas C(4v) conformation becomes important at higher salt concentration. It is found that the aggregation of Li(+)-PF(6)(-) complexes occurs in all four molar ratios, whereas ionic conductivity decreases and viscosity increases at higher salt concentration. The residence time correlation of PF(6)(-) within the first solvation shell of Li(+) shows a strong memory effect. The Li(+)-hopping function further shows that the hopping of Li(+) is strongly affected by its environment with different exchange rates of the PF(6)(-) anions for the structure diffusion, and the system of 0.5 LiPF(6)/EMMIPF(6) molar ratio has the slowest hopping rate.

In this paper, we propose a new efficient algorithm for globally solving a class of Mixed Integer Program (MIP). If the objective function is linear with both continuous variables and integer variables, then the problem is called a Mixed Integer Linear Program (MILP). Researches on MILP are important in both theoretical and practical aspects. Our approach for solving a general MILP is based on DC Programming and DC Algorithms. Using a suitable penalty parameter, we can reformulate MILP as a DC programming problem. By virtue of the state of the art in DC Programming research, a very efficient local nonconvex optimization method called DC Algorithm (DCA) was used. Furthermore, a robust global optimization algorithm (GOA-DCA): A hybrid method which combines DCA with a suitable Branch-and-Bound (B&B) method for globally solving general MILP problem is investigated. Moreover, this new solution method for MILP is also applicable to the Integer Linear Program (ILP). An illustrative example and some computational results, which show the robustness, the efficiency and the globality of our algorithm, are reported.

Electrical stimulation of the optic nerve has been identified as a form of visual prosthesis to restore lost vision in blind patients affected by retinitis pigmentosa and age-related macular degeneration, through many studies and experiments. Magnetic transcutaneous coupling is frequently used for power transfer to implanted electronic devices. In such a prosthetic device, how to improve the power transfer efficiency and how we can get a precise DC voltage output are the two of the most challengeable elements in the whole system design. This paper presents the use of a transmitter coil driver based on the class-E amplifier. The closed-loop class-E circuit shows a great promise, especially for the circuits with unusually low coefficients of coupling. The transfer system is designed to a high-Q system and it can compensate for the transmitter and receiver variations via a smart feedback system. The system is optimized to minimize the power losses. This paper also describes the design of a data transfer system. This part can deliver the processed digital information that is useful for the implanted stimulator from the external side to the internal side (implant).