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A miniature ionization vacuum sensor (IVS) based on an on-chip SiOx-based tunneling electron source is reported. The vacuum sensor fabricated by microfabrication technologies exhibits a compact multilayered structure with overall dimensions of $13\times 9\times2.7$ mm3, where the electron source chip, Si layer of the electron collector, Si layer of the ion collector, and glass spacers between them are stacked together by an anodic bonding method. Electron impact ionization occurs in a semiclosed cavity through the electron and ion collector layers and glass spacers. Because of the compact structure, low working voltage of SiOx-based tunneling electron sources, and stable electron emission of the electron sources in a poor vacuum, a wide linear detection range from $1.3\times 10^{-2}$ to 133 Pa and a sensitivity of $8.3\times 10^{-4}$ Pa−1 have been demonstrated for the devices. These advantages, including miniature size, a detection range up to the rough vacuum regime, and the capability of batch fabrication with microfabrication technologies, make our IVSs promising in vacuum measurements.

Thermionic electron sources are scaled down to the microscale on a chip and batch fabricated on 4-in silicon wafers by utilizing microfabrication technologies and exploiting carbon nanotubes as microscopic filaments of thermionic electron emission. The microfabricated on-chip thermionic electron sources not only satisfy the metrics of compactness and ease of batch fabrication, but also exhibit the advantages of good performance reproducibility (±6.9% variation over 100 test cycles under a driven voltage of 3.5 V) and high emission stability (fluctuation < 5% for emission current level of ≈10−8 A over 900 s) under a relatively low vacuum condition (10−4–10−2 Pa). Furthermore, to extract electrons and tune emission current, an extraction gate with a mesh is monolithically integrated with the thermionic electron sources using anodic bonding technique. The integrated electron sources exhibit a strong gate controllability and a considerable electron transmission ratio of ≈76% through the extraction gate. All these results make our devices a promising type of on-chip electron source in the applications of miniature vacuum electronic devices/systems.

In order to meet the needs of the development of low-rise assembly structure in rural areas, a fabricated light-weight steel frame-composite light wall structure is proposed in this paper. The light-weight steel frames are used to bear the vertical loads. The single-row-reinforced recycled concrete wall-boards are used as lateral members to resist most of the horizontal earthquake loads. The wall-board, EPS (Expanded Polystyrene) insulation modules, and fly ash blocks form the thermally insulated wall. Four fabricated lightweight steel frame-composite light wall structures and one light-weight steel frame (FRA) structure were tested under the low cyclic loads. The influence of wall reinforcement spacing and structural form (be it fly ash block or not) on the seismic performance of this new structure was analysed and the damage process of the specimen was simulated using the ABAQUS® software. The results show that the light steel frames and the single-row-reinforced recycled concrete wall-board can work well together. Furthermore, the structure has two clear seismic lines. Due to the use of EPS insulation modules and fly ash blocks, the structure has good anti-seismic and thermal insulation abilities. Reducing the spacing of bars or compositing fly ash blocks can significantly improve the seismic performance of the structure. The finite element method (FEM) calculations agreed well with the experimental results, which validates the proposed model.

In order to investigate the construction of column-to-beam joints and to understand theeffect of recycled aggregate concrete (RAC) and cross-section of beams and columns on theseismic performance of recycled aggregate concrete-filled light steel tubular frame structure, fournew types of assembly joints were proposed in this paper. A low cyclic loading test of six framespecimens was carried out. The failure characteristic, load bearing capacity, hysteresis property,ductility, strength and stiffness degradation, and energy dissipation were analysed. The damageprocess of the specimen was simulated using the ABAQUS software, and the results agreed wellwith those obtained from the experiments. The results showed that the construction pathway of thejoints exhibited significant influence on the seismic performance of the frame. The proposedreinforced joint (using angle steel and stiffeners) significantly improved the bearing capacity,stiffness and energy dissipation capacity of the recycled aggregate concrete-filled steel tube frame.The seismic performance of the steel frame was improved, while the energy dissipation capacityincreased by 635.7% using RAC filled in the steel tubes. Finally, by appropriately increasing thesize of cross-section on the beams and columns can improve the bearing capacity, stiffness andductility of the structure.

Therapy strategy toward epidermal growth factor receptor (EGFR) inhibition in cervical cancer has been ongoing. EGFR promoter methylation status and EGFR tyrosine kinase inhibitor-sensitive mutations in cervical cancer may be significant for clinical outcome prediction using anti-EGFR treatment. In this study, EGFR tyrosine kinase inhibitor-sensitive mutations, EGFR exons 18, 19, and 21 mutations, were detected by sequencing in a total of 293 Chinese cervical squamous cell carcinoma tissue samples. EGFR promoter methylation status was detected by an EGFR asymmetric PCR and hybridization-fluorescence polarization assay and sequencing in 293 Chinese cervical squamous cell carcinoma tissue samples. High-risk human papillomavirus (HPV) genotypes in 293 Chinese cervical squamous cell carcinoma tissue samples were detected by an asymmetric GP5+/6+ PCR and hybridization-fluorescence polarization assay. No EGFR exons 18, 19, and 21 mutations were detected, EGFR promoter methylation status was identified in 98 samples, and HPV 16 infection was the first frequent HPV genotype. The methylated EGFR promoter was identified most frequently in cervical squamous cell carcinoma samples with HPV 16 infection (53.4%). Statistical significant difference of EGFR promoter methylation prevalence was found between HPV 16 and other HPV genotypes (P

This paper analyzes the influence of solar radiation on the prestressed concrete wide box girder with a large cantilever. The experimental research is carried out by arranging the embedded deformation monitoring sensor, and the actual temperature deformation curve of the large cantilever box girder subjected to solar radiation is obtained. Besides, the deformation calculation model of box girder under the influence of solar radiation is established by ANSYS finite element software, so as to obtain the deformation distribution of large cantilever prestressed concrete under solar radiation. Calculation results are fitting well in with the actual tested results, with an average error of 7.97%. As the boundary conditions are quite ideal, the tested results tend to be larger. Relative studies can provide some guidance and suggestions for the deformation control and design of this type of bridge.

In order to quantitatively evaluate the shear-bearing capacity of shear connectors of square concrete filled steel tube (CFST), push-out tests on 14 square CFSTs with shear connectors have been carried out. Among the 14 CFSTs, there are 13 specimens with steel plate connectors and one specimen with steel bar connectors. The following factors are investigated to figure out their influences on the performance of CFSTs, which are the width to thickness ratio of steel tube, thickness of steel plate, length of steel plate, strength of concrete, welding condition of steel plate, number of steel plate layer and interlayer spacing. The test results show that the ultimate bearing capacity and the elastic stiffness increase with decreasing width to thickness ratio of the steel tube, and increasing thickness and length of the steel plate. With increasing concrete strength, the ultimate bearing capacity also increases. However, the welding condition has no effect on the ultimate bearing capacity. The ultimate bearing capacity of the CFST with double-layer steel plate is greater than that with single-layer steel plate. The ultimate bearing capacity of steel bar type shear connector is 87% greater than that of the steel plate type shear connector, and the steel bar specimen shows good ductility. A formula for calculating the shear-bearing capacity of shear connectors has been developed, and the calculated shear-bearing capacities are in good agreement with the test data.

Medical condition of commercial driving license drivers (CDL drivers) has a direct influence on public traffic safety. Recently, a series of traffic accidents, caused by sudden giddiness of drivers, has reflected that this influence is not always on a positive level. Analyzing the feasibility and development of the current declaration mode for drivers’ medical condition based on laws and regulations, management mode, medical method and operational program, this paper suggests a set of safety loophole screening methods of CDL drivers’ medical condition.

This paper summarizes an engineering experience of solving the problem of thermal cracking in mass concrete by using a large project, Zhongguancun No.1 (Beijing, China), as an example. A new method is presented for controlling temperature cracks in the mass concrete of a foundation. The method involves controlled cycles of water circulating between the surface of mass concrete foundation and the atmospheric environment. The temperature gradient between the surface and the core of the mass concrete is controlled at a relatively stable state. Water collected from the well-points used for dewatering and from rainfall is used as the source for circulating water. Mass concrete of a foundation slab is experimentally investigated through field temperature monitoring. Numerical analyses are performed by developing a finite element model of the foundation with and without water circulation. The calculation parameters are proposed based on the experiment, and finite element analysis software MIDAS/CIVIL is used to calculate the 3D temperature field of the mass concrete during the entire process of heat of hydration. The numerical results are in good agreement with the measured results. The proposed method provides an alternative practical basis for preventing thermal cracks in mass concrete.

The seismic performance of recycled aggregate concrete (RAC) composite shear walls with different expandable polystyrene (EPS) configurations was investigated. Six concrete shear walls were designed and tested under cyclic loading to evaluate the effect of fine RAC in designing earthquake-resistant structures. Three of the six specimens were used to construct mid-rise walls with a shear-span ratio of 1.5, and the other three specimens were used to construct low-rise walls with a shear-span ratio of 0.8. The mid-rise and low-rise shear walls consisted of an ordinary recycled concrete shear wall, a composite wall with fine aggregate concrete (FAC) protective layer (EPS modules as the external insulation layer), and a composite wall with sandwiched EPS modules as the insulation layer. Several parameters obtained from the experimental results were compared and analyzed, including the load-bearing capacity, stiffness, ductility, energy dissipation, and failure characteristics of the specimens. The calculation formula of load-bearing capacity was obtained by considering the effect of FAC on composite shear walls as the protective layer. The damage process of the specimen was simulated using the ABAQUS Software, and the results agreed quite well with those obtained from the experiments. The results show that the seismic resistance behavior of the EPS module composite for shear walls performed better than ordinary recycled concrete for shear walls. Shear walls with sandwiched EPS modules had a better seismic performance than those with EPS modules lying outside. Although the FAC protective layer slightly improved the seismic performance of the structure, it undoubtedly slowed down the speed of crack formation and the stiffness degradation of the walls.

In view of the problem that the traditional sub pixel edge extraction method is obviously deviated from the real edge near the corner. A new algorithm is proposed. In this paper, the corner protection function is added to the level set energy functional, which makes that the evolution of level set function is restricted at the corner, therefore this algorithm can improve the accuracy of edge extraction near the corner. The sub pixel edge extraction results of simulated and real images show that the proposed method is more accurate at the edge of the corner.

For the surface water body extraction from China GF-1 satellite multi-spectral images, this paper proposes a algorithm based on the LBV transformation analysis method. The LBV transformed images can be used more effectively for the analysis of ground features than the original multispectral satellite images. So in the proposed method, the LBV transformation equations for GF-1 images are firstly discussed. Then, by analyzing gray level curves of six typical ground features in L(the general radiance level), B(the visible-infrared radiation) and V(the band radiance variation vector) images respectively, a decision criterion for extracting water body is obtain. And by this decision criterion the water bodies can be quickly and accurately extracted in the complex scenes. The experimental results show that this algorithm can effectively eliminate roads and the shadows of the buildings and cloud on the influence of the water body extraction and can exactly extract the small ponds, lakes and reservoirs. In addition, the proposed algorithm is simple, automatic and highly adaptable.

A high-accuracy signal processing algorithm was designed for the absolute distance measurement system performed with frequency scanned interferometry. The system uses frequency-modulated laser as light source and consists of two interferometers: the reference interferometer is used to compensate the errors and the measurement interferometer is used to measure the displacement. The reference interferometer and the measurement interferometer are used to measure synchronously. The principle of the measuring system and the current modulation circuit were presented. The smoothing convolution was used for processing the signals. The optical path difference of the reference interferometer has been calibrated, so the absolute distance can be measured by acquiring the phase information extracted from interference signals produced while scanning the laser frequency. Finally, measurement results of absolute distances ranging from 0.1m to 0.5m were presented. The experimental results demonstrated that the proposed algorithm had major computing advantages.