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A balanced substrate-integrated waveguide (SIW) bandpass filter (BPF) is designed and fabricated based on through-quartz-via (TQV) technologies in this article. Sixth-order filtering response centered at 41.4 GHz with equal source and load termination is achieved by the transformation of the Chebyshev polynomial. By exploiting cross-coupled resonators, the 3-dB fractional bandwidth (FBW) achieves 12.1%, and the out-of-band rejection is better than 30 dB with frequencies up to $2f_{0}$ . High CM suppression can be achieved up to $2.2f_{0}$ with the help of two slots on the bottom metal layer. Based on the theory of the proposed SIW BPF, asymmetric diplexer with different resonance orders for two channels is studied with high isolation and wide stopband. The mixed dual-mode (TE101 and TE301) and single-mode (TE101) junction resonators provide a transition between the input port and two channels. Diplexer with lower and upper channels centered at 20.2 and 37.5 GHz, respectively, is fabricated and measured to verify the proposed structure, which exhibits high isolation better than 40 dB over the whole band and a wide stopband up to $3f_{0}$ of the lower channel. Measured results are in good agreement with the simulations.

This article presents a novel pico-watt voltage reference (VR) circuit whose power consumption is well controlled at high temperature. Unlike a traditional pico-watt VR circuit whose power consumption increases exponentially with temperature, the power consumption in this article increases linearly with temperature, thus saving much energy at high temperature. It generates the reference voltage through a 2-transistor (2-T) structure and a current generator to well control the current versus temperature. In the current generator, a gate leakage transistor replaces a huge resistor, thus saving 4-mm2 area. Fabricated in a 0.13- $\mu \text{m}$ CMOS process, this VR circuit generates a reference voltage of about 560 mV and shows an average temperature coefficient (TC) of 18.4 ppm/°C after trimming across −25 °C to 85 °C and a line sensitivity (LS) of 0.15%/V, while consuming 20 pW at 1-V ${V} _{\text {DD}}$ and 27 °C. The power consumption at 3.3-V ${V} _{\text {DD}}$ and 85 °C is 114 pW, which is at least two times smaller than reported in state-of-the-art work at high temperature. The core area is 0.003 mm2.

Concrete encased CFST (CECFST) column is a composite member consisted of outer encased concrete and inner CFST. Currently, a cast-in-place connection between a CECFST column and a reinforcement concrete beam is generally employed in engineering practice due to the outer encased concrete hinders the application of assembled connection, and the steel beam is usually connected to the CECFST column by on-site welding. In this paper, a novel on-site assembled connection between a CECFST column and a steel beam was proposed. In considering various material models and complex contacts, a FE model for this type of joint was established and verified. Further, parametric analyses of the assembled connections to concrete encased CFST columns were conducted to analyze the structural behavior. More importantly, an extended component model was developed to cover the feature of CECFST column focusing on the initial stiffness and moment resistance of the assembled connection. The load transfer mechanism for bolt in tension and beam flange in compression were considered in the modelling for evaluating the stiffness and strength of column wall in tension and in compression, respectively. The numerical results from the parametric analyses coincided well with the predicted results. The numerical and analytical results declared that this novel assembled connection between the CECFST column and steel beam performed favorable structural behavior and could be employed in assembled structures with CECFST columns.

Lateral flow immunoassay (LFA) strips are extensively used for rapid tests of various biochemical molecules, but these strips still have some limitations in bacterial detection due to their low sensitivity and poor stability in complex samples. In this study, we reported a highly sensitive and quantitative fluorescent LFA strip for bacterial detection by using novel magnetic-core@dual quantum dot (QD)-shell nanoparticles (Fe3O4@DQDs) as multifunctional fluorescent labels. The Fe3O4@DQDs were prepared through a polyethyleneimine (PEI)-mediated layer-by-layer (LBL) assembly method, and they possess monodispersity, high magnetic responsiveness, good stability, and superior fluorescence properties. Based on these merits, the Fe3O4@DQDs were used to capture and enrich bacteria from complex samples and then used as advanced fluorescent labels of LFA strips for the quantitative detection of bacteria. Under optimal conditions, the assay ultra-sensitively detected Streptococcus pneumoniae with a low limit of detection of 8 cells per mL and a wide dynamic linear range of 10 cells per mL to 107 cells per mL. Systematic comparison revealed that the fluorescence detection limit of the Fe3O4@DQD-based strip was 55 and 1000 times higher than those of Fe3O4-core@QD-shell nanocomposite (Fe3O4-QD)-based and conventional QD microsphere-based strips, respectively. The proposed method also exhibited high specificity and selectivity for biological samples (human whole blood and sputum) and is thus a promising tool for real bacterial sample testing.

A bandwidth optimization model for a novel equivalent 90° transmission-line section is proposed in this paper. Furthermore, the structure of 3-D compact 3-dB branch-line directional coupler and its equivalent-circuit model are presented. They can achieve both excellent isolations between each branch and high-density integration by using equivalent 90° transmission-line sections and coaxial through-silicon via technology in 3-D integrated circuits. Finally, a 3-D coupler is designed with the center frequency of 100 GHz, as well as the bandwidth and size reach 20 GHz and $174\times 236.9\times 208.7\,\,\mu \text{m}^{3}$ , respectively. The results of the 3-D full-wave field solver High-Frequency Structure Simulator and the proposed model are well matched, showing that the proposed model can be used to quickly evaluate the electrical performance of the 3-D coupler before manufacture, thus effectively promoting the design efficiency and quality.

A wideband equivalent-circuit model of coaxial-annular through-silicon vias (TSVs) for three-dimensional (3-D) integrated circuits is proposed in this paper. Rigorous closed-form formulas for the resistance and inductance of coaxial-annular TSVs are derived by computing the longitudinal electrical field in Cu and the longitudinal magnetic vector potentials in ${\rm{SiO}}_{2}$ and Si substrate with Bessel functions. The equivalent-circuit model can appropriately capture the skin effect in Cu as well as eddy-current effect in Si substrate. The proposed model is verified using 3-D full-wave field solver high frequency simulator structure, showing that it can yields highly accurate results up to 100 GHz.

In this article, an application of superelastic shape memory alloy strands for improving the seismic performance of unbonded prestressed reinforced concrete bridge column is proposed. In the reinforced concrete column with unbonded prestressing steel-shape memory alloy strands, superelastic shape memory alloy strands are put in series with unbonded steel strands, and the loading plateau of shape memory alloy is exploited to limit the increase in the axial load of column under an earthquake. Quasi-static analysis and seismic analysis were conducted to compare the seismic performance of conventional reinforced concrete column, reinforced concrete column with unbonded prestressing steel strands, and the proposed reinforced concrete column with unbonded prestressing steel-shape memory alloy strands. Result shows that reinforced concrete column with unbonded prestressing steel-shape memory alloy strands has larger ultimate displacement capacity than reinforced concrete column with unbonded prestressing steel strands in the quasi-static analysis. In the seismic analysis, reinforced concrete column with unbonded prestressing steel-shape memory alloy strands suffers from smaller earthquake residual displacement than reinforced concrete column and reinforced concrete column with unbonded prestressing steel strands. Furthermore, parametric analysis was carried out to investigate the effects of unbonded steel strand ratio, prestressing force ratio, bonded longitudinal reinforcement ratio, and maximum tensile force ratio (area of shape memory alloy strands) on the ultimate displacement and quasi-static residual displacement of reinforced concrete column with unbonded prestressing steel-shape memory alloy strands. Results show that increasing the prestressing force ratio and the maximum tensile force ratio within certain ranges can improve the self-centering capability of column. Increasing the area of bonded longitudinal reinforcement and unbonded steel strand ratio results in larger residual displacement.

The 3-D multistrata integration puts forward high requirements for signal integrity. The shielded-pair through-silicon vias (SPTSVs) proposed in this paper feature superior transmission properties and high jamming immunity suitable for differential-mode and common-mode transmission. Based on the quasi-static field theory, a wideband impedance model of SPTSVs considering the proximity effect, the line-to-line crosstalk, and the eddy current effect is derived. The parasitic parameters calculated by the impedance model are further given. The finite-element analysis shows that the proposed model highly agrees with the 3-D full-wave simulation and the analytical calculation. In addition, the characteristics of the impedance and the transmission coefficient are deeply analyzed with different design parameters. Finally, the impacts of the substrate effect and the metal–oxide–semiconductor effect on electrical characteristics of SPTSVs are revealed.

Continued reduction in transistor size can improve the performance of silicon integrated circuits (ICs). However, as Moore's Law approaches physical limits, high-performance growth in silicon ICs becomes unsustainable, due to challenges of scaling, energy efficiency, and memory limitations. The ultra-thin layers, diverse band structures, unique electronic properties, and silicon compatible processes of two-dimensional (2D) materials create the potential to consistently drive advanced performance in ICs. This review presents the potential of fusing 2D materials with silicon ICs to minimize the challenges in silicon ICs, and to create technologies beyond the von Neumann architecture. It discusses the killer applications for 2D materials in logic and memory devices to ease scaling, energy efficiency bottlenecks, and memory dilemmas encountered in silicon ICs. The fusion of 2D materials allows the creation of all-in-one perception, memory and computation technologies beyond the von Neumann architecture to enhance system efficiency and remove computing power bottlenecks. Progress on the 2D ICs demonstration is summarized, as well as the technical hurdles it faces in terms of wafer-scale heterostructure growth, transfer, and compatible integration with silicon ICs. Finally, the promising pathways and obstacles to the technological advances in ICs due to the integration of 2D materials with silicon is presented. This article is protected by copyright. All rights reserved.

By utilizing coaxial through-silicon via (TSV) technology, compact L C low-pass filters (LPFs) are proposed. Firstly, several capacitors based on coaxial TSV are investigated, in detail, by means of analytic calculation, finite element method (FEM) simulation, and measurement. Secondly, a formula for the inductance of coaxial TSV-based spiral inductors is proposed and verified by FEM simulations and measurements. Finally, based on the investigation of TSV-based capacitors and inductors, an analytical model of the proposed L C LPFs based on 2 × 4 , 2 × 5 , 2 × 6, and 2 × 7 coaxial TSV arrays is proposed, and the equivalent circuit model and the finite element method (FEM) model are established in ADS and HFSS, respectively. The LPFs are fabricated and verified through measurements. In the proposed LPFs, coaxial TSVs are used as capacitors and inductors simultaneously, which leads to a more compact size. The parasitic capacitance of the inductors can, helpfully, induce a notch point for the proposed LPFs in stopband and improve the roll-off rate.

Unbonded prestressed reinforced concrete column (UBPRC column) has become an attractive approach in the field of bridge seismic design due to its superior self-centering behavior. Unbonded prestressing bar in a UBPRC column functions as a self-centering element and longitudinal mild reinforcement functions as an energy dissipator. Quasi-static cyclic test was carried out in this study to compare the seismic performance of reinforced concrete column (RC column), UBPRC column and fully prestressed concrete column (FPC column). The result shows that the UBPRC column has higher post-yield stiffness and smaller quasi-static residual displacement, but lower energy dissipation capability than the RC column. The FPC column suffers from the least quasi-static residual displacement, but has the lowest energy dissipation capability, the least ultimate displacement and the most severe prestress loss. The quasi-static residual displacement and residual crack width of the UBPRC column are around 66% and 73% of those of the RC column, respectively. The failure patterns of the RC column and the UBPRC column are similar, while the failure pattern of the FPC column is similar to that of a rocking column. The self-centering behavior of the three columns was analyzed and quantified using a self-centering index, which can be recommended for use in the seismic design of bridge columns.

The three-dimensional integrated circuits (3D ICs) based on through silicon via (TSV) technology offer a solution to meet the continuously increasing demand on high-speed electronic products. In order to comprehensively evaluate the signal transmission of TSV in increasing signal frequency, accuracy equivalent circuit model is necessary. In this paper, a method of double-T type equivalent circuit modelling for TSVs is proposed and applied to coaxial TSV and ground-signal (GS)-type TSVs. Furthermore, the transmission parameters (S21) of the double-T models are evaluated by SPICE and compared with the results of 3-D full-wave electromagnetic field simulation (HFSS). The good accordance of the results up to 50GHz verifies the accuracy of the proposed method.

The polymer-cavity through-silicon vias (TSVs) on low resistivity silicon (LRSi) are proposed in this letter to reduce the conductive substrate losses for microwave applications, due to that the coupling loss of conventional LRSi is considerable in high speed three-dimensional integrated circuits (3-D ICs). The accurate wideband equivalent circuit model and simplified π-model are derived based on the physical design parameters, which are established by the ADS software. Well agreements between the proposed models and 3D full-wave EM field simulation of Ansoft's HFSS are shown with the operating frequencies up to 20 GHz.

A simple formula for the internal impedance of mixed carbon nanotube (CNT) bundles is proposed in this paper. It can appropriately capture the skin effect as well as temperature effect of mixed CNT bundles. The computing time and results of the simple formula and the numerical calculation are compared with various mean diameters, standard deviations, and temperatures. It is shown that the proposed simple formula can improve the efficiency dramatically, and has very high accuracy in the whole frequency range considered, with maximum errors of 1.2% and 2.5% for the resistance and the internal inductance, respectively.

Since the coupling loss of conventional low resistivity silicon (LRSi) is considerable in high speed three-dimensional integrated circuits (3-D ICs), air-cavity through-silicon vias (TSVs) on LRSi are proposed in this letter to reduce the conductive substrate losses for microwave applications. The $Q$ -factor and insertion loss are exploited to assess the effect of air-cavity TSVs. The accurate wideband equivalent circuit model and simplified $\pi$ -model are derived based on the physical design parameters, which are established by the ADS software. Well agreements between the proposed models and 3-D full-wave EM field simulation of Ansoft's HFSS are shown with the operating frequencies up to 20 GHz.

In this letter, Ground-Signal-Ground type through-silicon vias (TSVs) are designed to achieve millimeter wave applications in three-dimensional integrated circuits (3-D ICs). Air-gap is exploited as the insulation layer due to the low permittivity. The accurate wideband equivalent-circuit model are established with frequency up to 20 GHz by using a set of resistance inductance capacitance conductance (RLGC) parameters, which are derived from the different design physical parameters and materials of the TSVs. Good agreements between the proposed models and full-wave simulation of Ansoft's HFSS are shown over a wide frequency range of interest.

In this letter, the parasitic inductance of tapered ground-signal-ground (GSG) type through-silicon via (TSV) pair used in high speed three-dimensional integrated circuits (3-D ICs) are proposed. Rigorous closed-form formulas of the inductance, exploiting loop and partial inductances, are derived based on the geometric information with frequency up to 20 GHz, which also cover the cylinder and GS-mode TSVs. The proposed models are in good agreement with the 3-D electromagnetic (EM) simulator and measurement results with maximum errors of 8%.

"United Nations Convention on Contracts for the International Carriage of Goods Wholly or Partly by Sea" was passed in July 3, 2008. on September 23, 2009 signing ceremony was held in Rotterdam. The system of maritime performing party is a special system in the transport convention, and constitutes an integral part of the Convention. Maritime performing party system is not the first system which brings in the carrier's independent contractor, but it is the most comprehensive and thorough one. It unified the duty of carrier's independent contractor in the maritime segment, and it is also an important progress in the developing process of international maritime legal system. There are some differences between the maritime performing party and China's current related system, i.e, the port maritime performing party and the intermediate performing party are included in the maritime performing party, and they can enjoy the carrier's exception clause and limitation of liability.

Characteristic impedance of Through Silicon Via (TSV) differs from the transmission lines' in high speed three-dimensional integrated circuits (3D ICs), resulting in signal reflection and degrading the signal quality. We add a capacitance to the connection of TSV and interconnects to reduce the TSV-induced signal reflection in multilevel interconnect structures for frequencies up to gigascale. Simulation result indicates that the signal reflection can be weakened obviously from -3 dB to -25 dB with the help of matching capacitance, using S-parameter analysis in the technology of 65 nm node. For different circuits, we can choose appropriate matching capacitance to minimize the signal reflection according to the circuit parameters.

In this paper, ground-signal-ground type through-silicon vias (TSVs) exploiting air gaps as insulation layers are designed, analyzed and simulated for applications in millimeter wave. The compact wideband equivalent-circuit model and passive elements (RLGC) parameters based on the physical parameters are presented with the frequency up to 100 GHz. The parasitic capacitance of TSVs can be approximated as the dielectric capacitance of air gaps when the thickness of air gaps is greater than 0.75 μm. Therefore, the applied voltage of TSVs only needs to achieve the flatband voltage, and there is no need to indicate the threshold voltage. This is due to the small permittivity of air gaps. The proposed model shows good agreement with the simulation results of ADS and Ansoft's HFSS over a wide frequency range.