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В статье актуализируются вопросы устойчивого развития в контексте реализации принципов и моделей циркулярной экономики, показана роль цифровых технологий в содействии переходу к экономике замкнутого цикла и предлагают основу для циркулярной экономики 4.0. На взгляд автора, интеграция цифровых технологий может улучшить подходы и модели циркулярной экономики, обеспечивая более эффективное использование ресурсов, улучшенное отслеживание материалов, а также лучший мониторинг воздействия на окружающую среду. Циркулярная экономика рассматривается как перспективный подход к устойчивому развитию путем продвижения таких практик, как переработка ресурсов и минимизация использования энергии.

A novel type of austenite–martensite dual-phase laminate steel with a yield strength of 2.2 GPa, ultimate tensile strength of 2.5 GPa, uniform elongation of 9.4% and total elongation of 12% was produced. Such unexpectable mechanical properties were mainly due to the synergistic strengthening of nanolaminate microstructure, high densities of dislocations and nanoprecipitates. The high uniform elongation at very high stress could be attributed to the strongly enhanced work hardening rate, mainly enabled by transformation-induced plasticity (TRIP) of the austenite reverted by annealing, as well as the cooperative deformation and stress/strain partitioning between the austenite–martensite stacked nanolaminate. This work verifies an effective strategy of combining TRIP and maraging to achieve both ultrahigh strength and high ductility of steel.

Under the excitement of wind loads, UHV transmission lines are subject to two types of vibration phenomena, namely, sub-span oscillation and galloping. This phenomenon can easily lead to conductor breakage, interphase flashover, fatigue damage to fittings, and even lead to tower collapse and disconnection accidents. The numerical analysis method is used to analyze the sub-span oscillation characteristics of the eight-bundle conductor during galloping. The results of the numerical simulation are compared to explore the influence of wind speed, span length, initial angle of wind attack, and turbulence intensity on the galloping line, looking for movement characteristics between each sub-conductor. The results provide a reference for research on the galloping principle of UHV transmission line and anti-oscillation to further improve the resistance of the power grid against disaster ability.

This paper presents the results of experimental investigations on steel tube strengthened recycled concrete (STSRC) exposed to high temperatures and reinforced by CFRP. The failure mode, bearing capacity and deformability of the columns were investigated to analyze the effects of CFRP, temperatures (300°C, 500°C and 700°C), and recycled coarse aggregate (RCA) replacement ratios (0%, 50% and 100%) on mechanical performance. The results indicate that the higher exposed temperatures, the more cracks occurred and the lower ultimate load carrying capacities for the specimens, and the failure mode and load capacity could be increased greatly by external strengthened with CFRP sheets. However, the higher RCA replacement ratio could induced a smaller cracks and higher load capacity, and the specimens with 50% RCA ratio gave the highest load capacity when exposed to high temperature. In addition, the ABAQUS software was employed to conduct finite element analysis (FEA) of STSRC reinforced, and a comparison of results calculated using the proposed model exhibits good agreement with an experimental results.

This paper aims to investigate the influence of curing condition on compressive strength of low-calcium fly ash-based geopolymer concrete (FAGC) by preparing six mixtures. The results also show that the specimens cured at room temperature for one day and then cured at high temperature will be helpful to obtain materials with higher strength than that of directly cured specimens at high temperature. Additionally, cured at room temperature for one day and then cured at high temperature would weaken the adverse effect of wet curing on the growth of compressive strength.

CeO 2 is a promising material for the utilization of solar light in photocatalytic reactions. However, the major obstacle for these studies is the lack of reliable methods to incorporate the desired elements such as nitrogen into the crystal lattice of CeO 2 . In the present study, a nitrogen-doped CeO 2 thin film was synthesized by IBAD technique. With this technique, the nitrogen was heavily and uniformly doped into the CeO 2 thin films. XPS analysis clearly demonstrates the greatest N concentration of 25 mol% can be doped in CeO 2 thin films which is much higher than that obtained via traditional methods. The high resolution N 1s spectrum shows that nitrogen dopants are uniformly doped into CeO 2 lattice by substituting O. The XRD results indicate ion bombardment on the growing film surface does not alter the crystal structure of the film by itself. Instead, the heavy nitrogen doping induces smaller grain size of CeO 2 . The SEM images show that with the increase of N doping, the surface become smoother with smaller particle size. The heavily nitrogen doping also induces a red shift of the visible light absorbance from 380 nm to 450 nm.

A novel integratable planar T-junction waveguide power divider with anti-phase outputs and full bandwidth of standard WR28 waveguide is proposed. It is basically a E-plane waveguide T-junction with its input port rotated around the axis of the two output ports by 90 degrees to form a planar structure. In order to verify the concept, a standard waveguide port THE junction divider is designed as an example. From the results, the reflection coefficient is lower than −20dB and phase difference between the two output ports is within 180 degrees in the full bandwidth from 26.3 to 39.4GHz.

The extremely low cycle fatigue (ELCF) behaviors of anti-seismic steel HRB400 reinforcing steel bars were comprehensively studied following the cyclic push-pull loading tests with extremely high strain amplitudes (up to ±12.8%). The cyclic stress response characteristics and cyclic stressstrain relationships were investigated. The cyclic response characteristics were closely related to the strain amplitudes, and the secondary hardening phenomenon appeared under some strain amplitudes. The strain-life data from the axial tests were used to derive suitable Coffin-Manson parameters for the test material. The scanning electron microscope (SEM) morphology revealed ELCF damage mechanisms were distinctive of those typical from LCF. Compared with the common low-cycle fatigue (LCF) fracture region, several unique features in the ELCF regime can be noticed, including the deviations of the fatigue life from the Coffin-Manson law and the transformation of fatigue cracking modes.

Pyrolusite slurry was used as absorbent to remove NO x from flue gas. Reaction mechanism of NO x removal was theoretically analyzed based on E-pH diagram of Mn–NO x –H 2 O system and then verified by experiments via both the qualitative and quantitative analysis of reaction products. Main reaction and byproduct were also investigated in depth. Results showed that NO x in flue gas dissolved into liquid phase first and then were oxidized into NO 3 - by MnO 2 and O 2 . NO 2 was more easily removed than NO because of its high solubility. NO x removal efficiency was depended strongly on the molar ratio of NO 2 to NO x (NO 2 /NO x ratio). When NO 2 /NO x ratio at 75%, NO x removal efficiency remained between 60% and 64% within 11 h and manganese extraction rate reached 92%. Manganese nitrate, meeting the needs of national industry grade standards, could be produced using purified absorption solution.

In order to make an effective use of the recycled aggregate concrete (RAC), a total of six steel tube RAC columns and six basalt fiber (BF) reinforced RAC columns, including six columns that were externally strengthened with aramid fiber reinforced polymer (AFRP) sheets, were fabricated and tested. This were to provide a strengthening solution to upgrade the load carrying capacity, ductility and rigidity of the RAC filled steel tube columns. Besides, the recycled coarse aggregate (RCA) replacement ratios for production of RAC was analyzed. The results show that the load carrying capacity and ultimate displacements of the RAC filled ST columns could be improved greatly by adding of basalt fiber, especially for the specimens with 50% and 100% RCA replacement ratio. The similar result was also found for the specimens strengthened with AFRP reinforcement, along with the stiffness of the columns were enhanced obviously. Moreover, the highest improving on the load carrying capacity, stiffness and ultimate displacement was found in the specimens both reinforced by adding of BF and strengthening of AFRP. However, the failure modes of the specimens with BF reinforced RAC gave a higher deformability than the one with AFRP strengthening arrangement.

Research on implementations of long range kick is a new trend coming up in RoboCup Soccer Simulation 3D competitions. Competition results show that, a team has more chance to defeat its opponent by applying long range kicks/shoots in both regular stage and penalty stage. This paper mainly proposes an approach that our team Apollo3D designed, to implementing a long range kick by adopting a spline interpolation method to generate kicking trajectories and a developed CMA-ES method to optimize parameters. In order to stabilize a robot when executing kicking, a preview controller is utilized to control the torso for keeping balance. After a number of tests, the average distance that a robot could send the ball to is increased by 74%.

This paper deals with the optimal energy-efficient control strategy of high speed train by means of the maximum principle with the speed limit constraints. Considering the variation and jump regulations of the co-state variable in two cases (with speed limit and without considering the speed limit), two types of transition diagrams are given respectively. According to the transition diagram, the types of transitions with touching the speed limit are classified into four base cases and other transitions are derived or combined from these four base cases. On this basis, the relationship between optimal operation and flat-out operation is discussed. Optimal operation with speed limit is close to the flat-out operation along with the decreasing of the operation time.

Corrosion and fatigue properties of aircraft materials are known to have a considerable scatter due to the random nature of materials, loading, and environmental conditions. A probabilistic approach for predicting the pitting corrosion fatigue life has been investigated which captures the effect of the interaction of the cyclic load and corrosive environment and all stages of the corrosion fatigue process (i.e. the pit nucleation and growth, pit-crack transition, short- and long-crack propagation). The probabilistic model investigated considers the uncertainties in the initial pit size, corrosion pitting current, and material properties due to the scatter found in the experimental data. Monte Carlo simulations were performed to define the failure probability distribution. Predicted cumulative distribution functions of fatigue life agreed reasonably well with the existing experimental data.

This paper focuses on the issue of CCD remote sensing image compression. Compared with other images, CCD remote sensing image data is characterized with high speed and high quantized bits. A high speed CCD image compression system is proposed based on ADV212 chip. The system is mainly composed of three devices: FPGA, SRAM and ADV212. In this system, SRAM plays the role of data buffer, ADV212 focuses on data compression and the FPGA is used for image storage and interface bus control. Finally, a system platform is designed to test the performance of compression. Test results show that the proposed scheme can satisfy the real-time processing requirement and there is no obvious difference between the sourced image and the compressed image in respect of image quality.

Cyclic material tests in the low cycle fatigue(LCF) regime were carried out to study the effect of frequency, strain ratio and specimen dimension on LCF life of high strength low carbon steel(cold-rolled Q235 steel). A total of 83 experiments were performed under uniaxial tension-compression loading with total strain control. The LCF behavior of the test material was found to be strong dependent on frequency and strain ratio, but weakly dependant on specimen dimension. The material displayed significant cyclic softening. The data obtained from the LCF tests were used to derive suitable Coffin-Manson parameters for the material. The results would provide reference on LCF tests and engineering application of cold-rolled Q235 steel.

Four Q345c steel beams with corrugated webs were tested by Shimadzu 4890 fatigue testing machine, the static and fatigue mechanical characteristics of the high-strength beams were studied from the experimental point. During the experiment, firstly a static tests was carried out by four-point bending, confirmed the conclusions of the bending moment of beam with corrugated steel webs mainly hosted by the upper and lower flange and verified the weak position and mode of its destruction; the other three beams were tested by the fatigue cycles load method with R=0.1, and the up fatigue load limit were 50%, 63%, 75% of the maximum static load respectively. The experimental phenomena showed that: in a situation of reasonable design and good geometric construction practices, tested by 50%, 63% maximum static load as fatigue loading, Q345c steel beams with corrugated webs remain intact after 200 million cycles; in the dynamic loads, the ultimate bearing capacity of the beam decreased to some extent.

An innovative embedded algorithm based on context model using neighboring coefficients and parent coefficients is proposed, which can implement real-time image processing and can achieve high fidelity. By analyzing the algorithm and implementation, it is found that the wavelet transform and bit-plane prediction have a great perplexity which can not be implemented efficiently. Based on multiple DSP hardware platforms, a architecture using parallelism and pipelining technology is present, which can reduce computation complexity and improve encoding efficiency. Experiment results show that the algorithm can achieve higher performance than JPEG2000 in terms of image quality and operating speed.

With the increasing demand for the development of high quality remote sensing image techniques, the problem of image degradation causing by pixel-response non-uniformity (PRNU) is becoming a key issue. In this paper, a novel PRNU correction algorithm is proposed and implemented on FPGA hardware platform. Firstly, the characteristic of the CCD noise is analyzed. Secondly, the degradation model of pixel-response non-uniformity is described and the correction algorithm is designed. Thirdly, the calculation precision is analyzed and the factors affecting the result of correction are analyzed. Finally, the proposed correction algorithm is tested in the hardware circuit. The experimental results show that SNR of the image is improved remarkably through correction processing.

Electromagnetic interference, shock and vibration under adverse conditions are critical problems for the design of embedded processing system, especially in the limited spaces. In addition, processing and transferring of large-scale image data are also important to the system. Therefore, in this paper an image data processing and storage system is designed, in which an ETX-CPU is used as the main module and a Virtex-II family FPGA acts as the processing core, at the same time, a well-appointed power processing circuit is designed to ensure the correctness of the system. In the end, CADENCE PCB layout design tools are used to solve the signal integrity problems of the system.

Objective: To measure setup error of head and neck neoplasm in radiotherapy and discuss over effects of error on physical dose acting on target region and organs at risk of nasopharynx cancer (NPC) patients treated with intensity modulated radiation therapy (IMRT). Methods: A total of 152 patients who developed head and neck neoplasm and received IMRT were randomly selected. Through comparing digital portal image and digital reconstruction image, we measured setup error, calculated expanding margin from clinical target volume (CTV) to planning target volume (PTV) and analyzed whether there was rules between setup error and treatment time. Additionally, 20 cases of NPC were selected. Three-dimensional error was simulated in planning system. Dose distribution was recalculated and a series of dose parameters of target volume and OAR were analyzed. Results: Setup error in left-right, head-feet and ventral-dorsal direction was (-0.62±1.46) mm, (-0.41±1.54) mm and (-0.31±1.67) mm respectively. Regarding limit value, the maximum and minimum value in left-right direction, head-feet direction and ventral-dorsal direction was 2.70 mm and -6.00 mm; 3.00 mm and -5.00 mm, 5.00 mm and -7.50 mm. Expanding margin from CTV to PTV was 2.26 mm, 1.88 mm and 1.97 mm in left-right direction, head-feet direction and ventral-dorsal direction. Conclusion: During IMRT, only when setup error is controlled below 3 mm can sharply reduce the damage caused by radiation to normal tissue; therefore, quality security and control of electronic portal imaging device need (EPID) to be improved.