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This paper studies the target controllability of multi-layer complex networked systems, in which the nodes are high-dimensional linear time invariant (LTI) dynamical systems, and the network topology is directed and weighted. The influence of inter-layer couplings on the target controllability of multi-layer networks is discussed. It is found that even if there exists a layer which is not target controllable, the entire multi-layer network can still be target controllable due to the inter-layer couplings. For the multi-layer networks with general structure, a necessary and sufficient condition for target controllability is given by establishing the relationship between uncontrollable subspace and output matrix. By the derived condition, it can be found that the system may be target controllable even if it is not state controllable. On this basis, two corollaries are derived, which clarify the relationship between target controllability, state controllability and output controllability. For the multi-layer networks where the inter-layer couplings are directed chains and directed stars, sufficient conditions for target controllability of networked systems are given, respectively. These conditions are easier to verify than the classic criterion.

This paper addresses the problem of the input design of large-scale complex networks. Two types of network components, redundant inaccessible strongly connected component (RISCC) and intermittent inaccessible strongly connected component (IISCC) are defined, and a subnetwork called a driver network is developed. Based on these, an efficient method is proposed to find the minimum number of controlled nodes to achieve structural complete controllability of a network, in the case that each input can act on multiple state nodes. The range of the number of input nodes to achieve minimal control, and the configuration method (the connection between the input nodes and the controlled nodes) are presented. All possible input solutions can be obtained by this method. Moreover, we give an example and some experiments on real-world networks to illustrate the effectiveness of the method.

This article investigates state controllability of high-dimensional linear networked systems with weighted topology, heterogeneous node dynamics, and nonidentical inner-coupling matrices. The focus is on how the node heterogeneity and nonidentical inner-coupling may affect the controllability of the system. It is found that the heterogeneous networked systems with nonidentical inner-coupling are controllable, even if the identically inner-coupled counterparts are uncontrollable, and vice versa. The finding also reveals the influence of the heterogeneity of the inner-coupling matrix on the network controllability. Some necessary and sufficient conditions for general linear systems with nonidentical inner-coupling, including some special cases to retain controllability, are derived. For typical structure networks, the controllability conditions depend solely on the specific form of the coupling matrix between a small number of nodes, but are independent of the coupling relationship between the remaining nodes. Some examples are given for illustration and verification.

In this paper, a novel direction of arrival (DOA) estimation algorithm using directional antennas in cylindrical conformal arrays (CCAs) is proposed. To eliminate the shadow effect, we divide the CCAs into several subarrays to obtain the complete output vector. Considering the anisotropic radiation pattern of a CCA, which cannot be separated from the manifold matrix, an improved interpolation method is investigated to transform the directional subarray into omnidirectional virtual nested arrays without non-orthogonal perturbation on the noise vector. Then, the cross-correlation matrix (CCM) of the subarrays is used to generate the consecutive co-arrays without redundant elements and eliminate the noise vector. Finally, the full-rank equivalent covariance matrix is constructed using the output of co-arrays, and the unitary estimation of the signal parameters via rotational invariance techniques (ESPRIT) is performed on the equivalent covariance matrix to estimate the DOAs with low computational complexity. Numerical simulations verify the superior performance of the proposed algorithm, especially under a low signal-to-noise ratio (SNR) environment.

With the development of aero-engine with high specific flux, high thrus-weight ratio, and high turbine inlet temperature, it is an effective way to improve the cooling efficiency by designing dense gas film holes on the blade surface of the turbine blades, especially at the intake side. However, the introduction of gas film holes destroys the geometrical integrity of the blade structure, resulting in a multiaxial high stress state of the blade material around the small holes, which seriously affects the strength and life of the cooling blades. In addition, the geometry design of the gas film holes also directly affects the temperature and the oxidation rate of the turbine rotor blades. In this paper, the researches on the mechanical properties and oxidative damage of the gas film holes at home and abroad in recent years have been systematically introduced. The effects of gas film holes on the durability and fatigue properties, the high temperature oxidation behavior of single crystal superalloys, and the thin-walled effect of oxidative damage of gas film holes have been systematically described.

A mixed-valence Cu(I)/Cu(II) coordination polymer, namely, [Cu2(L)(1,3-BDC)]n(1), has been synthesized under hydrothermal conditions (HL = 2-(2-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline and 1,3-H2BDC = 1,3-benzenedicarboxylic acid). Its structure has been determined by single crystal X-ray diffraction analysis and powder X-ray diffraction. The crystals are the monoclinic space group P21/cwith a= 10.686(4), b= 17.376(8), c= 11.759(4) Å, β= 92.072(14)°, C27H14Cu2FN4O4, Mr= 604.50, V= 2182.1(15) Å3, Z= 4, Dcalcd.= 1.84 g cm–3, R= 0.0588 and wR= 0.1202 (all data). In complex 1, the mixed-valence Cu(I)/Cu(II) atoms are linked by L and 1,3-BDC to give a rare 3D (3,3,4)-connected (4.7.9)(7.8.9)(4.7.8.93) framework. The temperature-dependent magnetic susceptibility of 1was investigated in the temperature range of 2–300 K.

A new Cd(II) coordination polymer, [Cd(CNA)]n(1) (H2CNA = 3-(carboxymethoxy)-2-naphthoic acid), was hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. The crystals are monoclinic, space group P21/cwith a= 16.9698(18), b= 7.8314(8), c= 8.9553(10) Å, β= 100.657(2)°, V= 1169.6(2) Å3, Z= 4, Dcalcd.= 2.03 g cm−3, μ(MoKα) = 1.9 mm−1, F(000) = 696 e, R= 0.0305, wR= 0.0784 for 172 refined parameters and 2285 data. Each CNA anion bridges three Cd(II) cations to give rise to a two-dimensional network structure. Topologically, if each CNA anion is regarded as a linker, and each Cd(II) atom considered as a 4-conencted node, the structure is simplified as a 4-connected (4,4) network. The solid state photoluminescent properties of the compound were also studied at room temperature.

Through-hole TiO2 nanotube arrays were successfully prepared by using mechanical coupling Ti/Ti foils as anode. By continuously anodization, one Ti foil was thoroughly fabricated into TiO2 nanotube arrays, and the bottom barrier of TiO2 nanotube arrays was extended to the other Ti foil layer. The physical gap between two Ti foils allowed the TiO2 nanotube arrays to be easily separated from the barrier layer. Thus the through-hole TiO2 nanotube arrays were obtained. The method is simple but effective to thoroughly remove the bottom barrier layer and obtain through-hole TiO2 nanotube arrays without any complicated processes.

In order to adjust the working points of the engine for a full hybrid bus, this paper proposed a set of optimization control method. In speed adjustment process, the rate of change was optimized and limited to avoid rapid and frequent change along with power required by the driver. Allow for complex engine model, fuzzy control method was introduced to regulate the torque response rate. Furthermore, dynamic amplitude upper and lower bound were limited to prevent system overshoot and oscillation. Nowadays, there are hundreds of busses operates in several public transport lines. Vast statistic data and experimental results verify the feasibility and effectiveness of the proposed control method in this paper. The vehicle has good fuel economy compared to the counterpart one, and the dynamic performance is also greatly improved.

LiMn2O4prepared by high temperature solid state reaction, pechini, and citric acid coordination methods was applied in selective catalytic reduction (SCR) of NO with NH3. MnO2was prepared by high temperature solid state reaction method and the activity was tested as a comparison. The catalysts were characterized by N2adsorption-desorption, scanning electron microscopy, X-ray diffraction, H2temperature-programmed reduction, NH3temperature-programmed desorption, NO temperature-programmed desorption, and X-ray photoelectron spectroscopy. The results showed that high-temperature activities of SCR were improved after the introduction of Li into MnO2. NO conversion on the LiMn2O4prepared by pechini method was above 90% in the range of 130–260°C; NO conversion on the LiMn2O4by high temperature solid state reaction method could be kept above 90% in the range of 90–310°C; while the temperature window of MnO2was only 140–280°C. Compared with MnO2, LiMn2O4crystal structure not only keeps more manganese cations at a relatively low valence of Mn3+, but also adjusts surface active oxygen. Meanwhile, the existence of Li adjusts surface-acid sites, thus alleviates the unselective oxidation of NH3in the high temperature, broadens the operating temperature window of NH3-SCR reaction, and improves the tolerance of SO2of MnO2.

With the increasing focus on developing environmentally benign electronic packages, Pb-free alloys have received a great deal of attention. Among the lead-free solder materials, Sn–Ag–Cu alloy has advantages of good wetting property, superior interfacial properties, high creep resistance and low coarsening rate. In this article, the organization and mechanical performance of Sn-Ag-Cu Material are investigated. Series of inspections and analytical research methods are introduced. Experimental results show that Sn-Cu solder organization contains a large number of Cu6Sn5 graphic, while Sn-Ag-Cu graphic is IMC Ag3Sn graphic. The mechanical propersity of Sn-Ag-Cu alloy is better than the Sn-Cu alloy. Fracture surfaces of the Sn-Ag3.0-Cu0.5 alloys specimen have many small size and homogeneously distributed dimples.

Dust particles and organic contaminants in environment can intrude into electronic device interior through the shell and opening holes. The intrusive contaminants can adhere on electric contact interface. Therefore, it can reduce components’ electric connection reliability. Widely it used acoustic dust-proof mesh to protect the mobile phone and other electric devices’ earpieces and speakers from contamination intrusion. This preventing contamination role makes much dust particles and organics adhere on the mesh. It is necessary to evaluate dust-proof mesh ability against contamination. In this paper, actual field contaminated meshes have been taken failure analysis. Then, lab simulation experiments have been established with considering meshes and contaminants’ characters. Finally the influence of mesh’s parameter on contamination has been researched.

The normal parameter reduction in soft set is difficult to application in data mining because of great calculation quantity. In this paper, the intelligent optimization algorithm, the harmony search algorithm, is applied to solve the problem. The normal parameter reduction model is constructed and the harmony search algorithm is designed. Experience has shown that the method is feasible and fast..

This paper develops an improved novel global harmony search (INGHS) algorithm for solving optimization problems. INGHS employs a novel method for generating new solution vectors that enhances accuracy and convergence rate of novel global harmony search (NGHS) algorithm. Simulations for five benchmark test functions show that INGHS possesses better ability to find the global optimum than that of harmony search (HS) algorithm. Compared with NGHS and HS, INGHS is better in terms of robustness and efficiency.

In this article, the corrosion behavior of the gold plating and the silver plating specimens are studied. It is found that the airtightness have effects on the contact properties of the different plating specimens. The surface morphology of specimens is observed by stereoscopic microscope and scanning electron microscope (SEM). Chemical constitution was examined by X-ray energy spectrum. The contact resistances were measured by four-point method. The experiment results show that the corrosion appearance of the silver plating is severer than that of the gold plating one after airtightness test. The corrosion degree of plating specimens decreased with the increase of the coatings thickness. The static contact resistances of corrosive spots appear higher contact resistance than normal value. It is found the high and unstable contact resistance of the corrosion products is more likely to cause contact failure. The influencing factor of the corrosion products with different plating has an important influence on the airtightness test and the contact failure of electric connector.

Glutaraldehyde (GA) cross-linked silk fibroin (SF) films were prepared and the structural change were investigated by Fourier transform infrared spectroscopy and differential scanning calorimetry. The results were utilized to reveal the influence of GA cross-linking on the release properties of SF materials. It was found that GA induced conformational transition of SF from random coil to beta-sheet and had influence on the interaction between the peptide chains of SF, resulting in great changes in mechanical and dissolution properties, as well as drug release feature of the films. With increasing GA content, tensile strength of films first increases and then decreases, reaching a maximum around 7.5 %. The cross-linking was found to increase the flexibility and stability of SF films in water, and reduce the burst release of Rhodamine B, a model compound for small drug. The release of Rhodamine B exhibited a continuous and steady release after the initial burst, of which the release rate had a good linear fit to beta-sheet content in the matrix, suggesting that the silk II crystal could be used as a natural regulator for drug release from SF material.

A wireless sensor network (WSN) consists of spatially distributed wireless sensor nodes. The node power constrains the development of WSN. Employing techniques of clustering can reduce energy consumption of wireless sensor nodes and prolong the network lifetime. Therefore, in the study a new clustering routing algorithm is presented. The clustering algorithm uses the double-layer sensor nodes to communicate. And in order to optimize power energy consumption for WSN node energy, PSO algorithm is employed to find cluster head in each layer. Simulation results show that the algorithm not only can equal power energy of node, but also can reduce consumption in the long distance data transmission.

In this paper, local synchronization problem of complex networks is theoretically and numerically studied. Base on the Lyapunov stability theory, a sufficient criterion for local synchronization of complex network which have the time-varying connection topologies is derived via designed decentralized linear controllers. And a numerical example of typical the Rössler network system with time-varying linear coupling has been used to demonstrate and verify the proposed. And, the simulation results show the effectiveness of proposed synchronization approaches.

In order to improve the performance of a new type of full hybrid electric bus, this paper puts forward a set of coordinated control method to adjust the operation of the engine and two motors. In the engine start-stop logic control, comprehensive consideration of SOC, the speed of the bus and the accelerator pedal stroke are performed, while hysteresis control is introduced to improve the stability of the control; In the engine working point adjusting control, not only the engine speed command rate of change was optimized, but also the output torque rate was optimized to match the air injection and exhaust, etc. Further, the method based on dynamic constraints was used to optimize the working point adjustment process. At present, there are hundreds of busses operates in route. Results verify the feasibility and effectiveness of the control method. The vehicle has good fuel economy, and the dynamic performance and driving comfort are also greatly improved.

A rapid and sensitive method was developed for the determination of trace amounts of Pb(ii) and Cd(ii) in aqueous solution using fiber-in-tube solid-phase microextraction (SPME) in combination with anodic stripping voltammetry (ASV). The main factors influencing the preconcentration and extraction of the metal ions, pH of the aqueous solution, filling mode, sample flow rate, eluent concentration, eluent volume, and eluent flow rate, were investigated. Under the optimized conditions, the process including preliminary enrichment by 100 times and ASV detection was completed within 20 min, and an adsorption percentage of >98% for Pb(ii) and Cd(ii) was obtained. The relative standard deviations at the limit of quantification (0.001 μg L−1) were 8.13% (n= 6) and 6.01% (n= 6) for Pb(ii) and Cd(ii), respectively. The fiber-in-tube SPME was applied for the determination of Pb(ii) and Cd(ii) in drinking water, and the recoveries were 95.0–102.3% and 99.9–107.4%, respectively.

The temperature control is one of the most common control system,with the development of the sensing technology, new single-bus digital temperature sensor to achieve faster development of the test and control of the temperature. The system is a temperature sensor AD590 to acquisition analog signals, after ADC0809 converted into digital signals to 89C51 single chip processing, so as to achieve the collection of temperature, and then through the CD4511 drive seven sections LED display. The system can control of temperature, through the keyboard for temperature of add or subtract Settings, if detection temperature is more than set temperature, stop heating, if detection temperature is below the set temperature, start heating. The system of design and wiring are simple,easy extension, cost-effective, volume is small, compact structure,strong anti-interference ability.

In this paper, following the state-feedback stabilization for time-varying systems proposed by Wolovich, a controller is designed for the overhead cranes with a linearized parameter-varying model. The resulting closed-loop system is equivalent, via a Lyapunov transformation, to a stable time-invariant system of assigned eigenvalues. The simulation results show the validity of this method.

Two new related coordination polymers, namely, [Pb(L)(1,4-ndc)] · 0.5H2O (1) and [Cd(L)(1,4- ndc)] · 0.5H2O (2), where L = 2-(3-fluorophenyl)-1H-imidazo[4,5-f][1,10]phenanthroline and 1,4- ndc = 1,4-naphthalenedicarboxylate, were synthesized under hydrothermal conditions. Crystal data for 1: C62H36F2N8O9Pb2, monoclinic space group C2/c, a = 15.874(3), b = 19.982(4), c = 16.045(3) Å, β = 94.26(3), V = 5075.3(18) Å3, Z = 4. Crystal data for 2: C62H36Cd2F2N8O9, monoclinic space group P21/n, a = 12.622(2), b = 14.038(3), c = 14.938(3) Å , β = 100.81(2), V = 2600.0(8) Å3, Z = 2. In compound 1, the 1,4-ndc ligands connect the Pb(II) atoms to yield a chain structure. The L ligands are attached on the same side of the chain. The π-π interactions between L ligands of neighboring chains result in a 2D supramolecular architecture of 1. In compound 2, 1,4-ndc ligands link the Cd(II) atoms to generate a layer structure. The L ligands from adjacent layers are paired to furnish strong π-π interactions. Further, these layers are extended into 3D supramolecular architectures through these π-π interactions. The structural differences of 1 and 2 suggest the importance of the metal centers in the construction of the coordination polymers. The luminescent properties of the compounds were also investigated.

FBG sensing character and model under three-dimensional stress are studyed in this paper. FBG center wavelength shifts of the two polarization directions are different and the shifts are determined by the changes of refractive index and the axial stain. The experiment indicates that the resonance peak wavelength shift amounts of the two directions are proportional to the transverse load.

Lowering power consumption and increasing noise margin have become two central topics in every state of the art SRAM design. Due to parameter fluctuations in scaled technologies, stable operation is critical to obtain high yield low-voltage, low-power SRAM. Recent published works in literature have shown that the conventional 6T SRAM suffers a severe stability degradation due to access disturbances at low-power mode. Thus, several 8T and 10T cell designs have been reported, improving the cell stability. However, they either employ single-ended read port or require too large area. In this paper, we use a fully differential 8T SRAM that allows efficient bit-interleaving to achieve soft-error tolerance with conventional Error Correcting Code (ECC). It also consumes less power when compared to the conventional 6T design. A column-based dynamic supply voltage scheme is utilized to improve both the read noise margin and the write-ability. To verify the technique, a 128 \times 64-bit of the proposed SRAM has been implemented in a standard 65 nm/1 V CMOS process. Simulation results reaffirmed that the proposed design has 2\times higher noise margin and consumes 54% less power when compared to the conventional 6T design. [ABSTRACT FROM PUBLISHER]

The title complex, [Mn2(glu)(L)2(HL)2]·0.5H2O (H2glu = glutaric acid, HL = 2-(2-chloro-6-fluorophenyl)-1Himidazo[ 4,5-f][1,10]phenanthroline) has been synthesized using a hydrothermal method and characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. Crystal data: C162H88Cl8F8Mn4N32O9, triclinic, space group P1¯, a = 14.932(5), b = 16.414(5), c = 17.891(5) Å , a = 115.851(5), ß = 91.288(5), ? = 112.894(5)?, V = 3536.4(19) Å3, Z = 1. Compound 1 exhibits 1D chains which are further stacked by C-H...p interactions to give two-dimensional supramolecular layers.

The effect of heat treatment on microstructures and stress rupture property of a Ni3Al base single crystal alloy DDIC6 was studied in the present investigate. The single crystal specimens were produced by screw selection crystal method. The heat treatment for the alloy was 1300°C/10h+1120°C/4h+870°C/32h and 1300°C/10h+870°C/32h.The microstructures were examined by SEM, TEM and X-ray EDS techniques. The stress rupture tests were carried out in air by constant load creep machines under 1100°C/130MPa with the specimens size of φ5×25 mm. The experimental results showed that the as-cast large size γ′ phases entirely dissolved after 1300°C/10h, and secondary fine γ′ phases precipitated by following aging at 1120°C and 870°C for certain periods of time. The stress rupture life under 1100°C/130MPa increased from 20~30hrs for as-cast condition to 60~100hrs for heat treatment condition. The improvement of the creep resistance of the alloy may attribute to the decrement of the elements segregation at dendrite and interdendritic areas, and the proper size and distribution of γ′ phases.

We derived the black hole fundamental plane relationship between the 1.4 GHz radio luminosity (Lr), 0.1-2.4 keV X-ray luminosity (LX), and black hole mass (M) from a uniform broad-line SDSS AGN sample including both radio-loud and radio-quiet X-ray-emitting sources. We found in our sample that the fundamental plane relation has a very weak dependence on the black hole mass, and a tight correlation also exists between the Eddington-luminosity-scaled X-ray and radio luminosities for the radio-quiet subsample. In addition, we noticed that the radio-quiet and radio-loud AGNs have different power-law slopes in the radio-X-ray nonlinear relationship. The radio-loud sample displays a slope of 1.39, which seems consistent with the jet-dominated X-ray model. However, it may also be partly due to the relativistic beaming effect. For the radio-quiet sample the slope of the radio-X-ray relationship is about 0.85, which is possibly consistent with the theoretical prediction from the accretion-flow-dominated X-ray model. We briefly discuss the reason why our derived relationship is different from some previous works and expect the future spectral studies in radio and X-ray bands on individual sources in our sample to confirm our result.

In hybrid electric vehicles, there is a set of electricity generating system. This system was modified to meet requirements of vehicle-mounted power plant. The new system is mainly composed of engine, generator, planetary gears, motor, battery, transfer case, control system and etc. and the planetary gears mechanism has two sets of planetary, control system includes vehicle controller, engine controller, motor controller, and inventor. This system can perform the functions which include vehicle driving, generating with vehicle ruining and generating with vehicle stopping. It can meet requirements of special purse vehicles.

The new coordination polymer [Cd(oct)(L)] (H2oct = octanedioic acid and L = 2-(4-fluorophenyl)-1H-imidazo- [4,5-f][1,10]phenanthroline) has been synthesized under hydrothermal condition and characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. Crystal data: C27H23CdFN4O4, monoclinic, space group C2/c, a = 21.391(4), b = 18.180(4), c = 14.031(3) Å , ß = 116.50(3), V = 4883(2) Å3, Z = 8. The flexible oct dianions bridge the Cd(II) cations to yield a double-chain structure. The L ligands are attached on both sides of the chains, and their p-p interactions between neighboring chains result in two-dimensional supramolecular layers

This paper discusses staple FRP T-joints on the project based on the classical beam theory of Euler-Bernoulli and a theoretical model of energy release rate is set up to discuss fracture propagation of composite T-joints. The paper is further analysis on fracture failure affected by composite pane depth and joints chamfer dimension parameters and so on. The conclusion benefit for extensive use of projects is also summarized.