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Copyright of Science Technology & Engineering is the property of Chinese Society of Technology Economics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Science Technology & Engineering is the property of Chinese Society of Technology Economics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to improve the level of process production safety management and reduce the probability of accidents, a functional safety integrity analysis method for risk prevention and control in the production process was proposed, and verified in conjunction with the steel continuous casting scenario. Firstly, the risk severity of primary accident types was evaluated, and an acceptable risk frequency standard was established. Secondly, the layer of protective analysis was employed to compute the actual occurrence frequency of high-risk accidents, determining whether the addition of new protective measures was necessary. Finally, validation of the safety integrity level of the introduced protective measures was carried out using the Monte Carlo-Markov model. The continuous casting operation area of the converter plant of Daye Special Steel Co., Ltd. was selected as the verification scenario. The results indicate that there are three high-risk accident hazards of molten material explosion, fire, and poisoning and suffocation, and the consequences of personnel casualties in molten material explosion accidents are unacceptable. Therefore, it is necessary to add protective measures with a functional safety integrity level of 2. An explosion protection system was designed with a failure probability of 4. 37 × 10-3, meeting the requirements of functional safety integrity level. [ABSTRACT FROM AUTHOR]

Copyright of Science Technology & Engineering is the property of Chinese Society of Technology Economics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Science Technology & Engineering is the property of Chinese Society of Technology Economics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The underground diaphragm wall-pile composite foundation is a new type of variable rigidity foundation which combines diaphragm wall with pile foundation. From the design concept, the combination of underground diaphragm wall-pile foundation has a better ability to resist lateral deformation and both economic. However, there is still a lack of systematic research on the mechanism of this new type of foundation from the perspective of mechanical characteristics. Based on the large-scale on-site model test conducted, the stress of the new type of composite foundation under horizontal load was simulated, and the variation law of load and displacement of the foundation were obtained by comparing the test and numerical simulation results. By analyzing the deformation characteristics of composite foundations under different levels of load, the load transfer law of the foundation was revealed, and a preliminary approximate calculation of the horizontal bearing capacity of the pile wall composite foundation was carried out. The results show that the composite foundation under horizontal load has been inclined to failure as a whole. The bending moment of the wall is much larger than that of the pile, the bending moment of the pile wall increases gradually with the increase of the loading grade, and the position of the maximum bending moment as well as the peak bending moment remain unchanged. With the increase of burial depth and load, the earth pressure on the wall side presents a non-linear change, the earth pressure on the side of the underground diaphragm wall is greater than that on the middle, and the maximum earth pressure appears in the middle and lower part of the underground diaphragm wall. [ABSTRACT FROM AUTHOR]

A new stereo matching algorithm called CSA-Net was proposed to solve the problem of the coexistence of lightweight and high-precision in stereo matching network models. In the feature extraction stage, ResNet-like feature extraction was employed and the empty pyramid pooling (ASPP) module was trained to expand the receptive field and extract multi-scale context information. Additionally, a joint attention mechanism (CSM) was added to improve the representation ability in the spatial and channel dimensions by focusing on important features and suppressing unnecessary ones. In the feature fusion stage, 2D depth separable convolution was extended to 3D to replace the standard 3D convolution in the original network to reduce the parameter amount and model running time of the feature fusion network. The experiment result validates the stereo matching network model proposed in this article on the KITTI 2012 and 2015 datasets, with the three pixel matching error rates being 1. 44% and 2. 24%, respectively. The model running time is reduced by nearly 1/3, leading to higher matching accuracy and faster running speed compared to other implementations. [ABSTRACT FROM AUTHOR]

Due to the poor fluidity of heavy oil in low temperature water environment, it is necessary to heat it during the extraction of heavy oil from the wreck. In order to study the thermal diffusion of heavy oil, the process of heating heavy oil and injecting hot oil into the heating rod was simulated, and the average thermal diffusion and spatial distribution in the oil tank was analyzed. The calculation results show that compared with the heating rod heating heavy oil, the temperature of the heavy oil in the oil tank is obviously improved after the injection of hot oil, and the injection of hot oil has a significant advantage in increasing the oil temperature and the speed of the oil. The calculation model is derived from practical engineering. The numerical analysis results can provide reference for the arrangement of heating rods for heavy oil recovery of sunken ships. The simulation of hot oil injection can solve the problem of slow flow of heavy oil in the oil tank and the difficulty of extracting heavy oil at the pumping port. [ABSTRACT FROM AUTHOR]

Copyright of Science Technology & Engineering is the property of Chinese Society of Technology Economics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to reasonably evaluate the impact of drought on desert grassland watersheds and accurately judge the transmission characteristics between meteorological drought and hydrological drought, taking the Aibugai River Basin as a typical research area, based on the monthly precipitation and runoff data of 57 years from 1965 to 2021, standardized precipitation index(SPI) and standardized runoff index(SRI) at three different time scales were calculated, and the evolution process, trend characteristics and correlation of meteorological drought and hydrological drought were analyzed. The results show that the application of SPI and SRI can well reflect the changes of meteorological drought and hydrological drought. The sensitivity of SPI value and SRI value to precipitation and runoff decreased with the increase of time scale, and the larger the time scale, the higher the frequency of high-grade meteorological drought events and hydrological drought events. The trend of meteorological drought events and hydrological drought events is increasing, and the degree and likelihood of hydrological drought are more severe than meteorological drought. The larger the time scale, the better thecorrelation between hydrological drought and meteorological drought, and the hydrological drought lags behind meteorological drought, with a lag of 0 ~ 1 month. The research results provide effective theoretical support for drought resistance and disaster reduction in desert grassland basins. [ABSTRACT FROM AUTHOR]

Copyright of Science Technology & Engineering is the property of Chinese Society of Technology Economics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Science Technology & Engineering is the property of Chinese Society of Technology Economics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Science Technology & Engineering is the property of Chinese Society of Technology Economics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The ideal seismic isolation device for electric cabinets should be locked under external excitation that does not affect the safety of the structure. When the device is subjected to earthquakes exceeding the structural fortification intensity, it is quickly unlocked to give full play to its seismic isolation capabilities. The acceleration trigger mechanism can switch the state switching between unlock and lock according to the ground motion acceleration. Therefore, it is an effective method to add an acceleration trigger mechanism to the seismic isolation device. In order to study the impact of acceleration trigger mechanism on the isolation performance of electric cabinets, a electric cabinet was selected as research object. A model of seismic isolation trigger electric cabinet was established through finite element software, and seismic time history analysis was performed to compare the isolation efficiency. Results show that the reasonable trigger limit of the acceleration trigger mechanism should be selected as 0.1g (g is gravitational acceleration). The isolation trigger cabinet's maximal acceleration response and seismic isolation rate are almost same as the isolation cabinet. The effect on the seismic isolation performance is minimal. This shows that the seismic isolation device with acceleration trigger mechanism, can be used as an ideal seismic isolation device for electric cabinets. [ABSTRACT FROM AUTHOR]

Copyright of Science Technology & Engineering is the property of Chinese Society of Technology Economics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to understand the effect of heat treatment on the mechanical property of the maraging steel 00Cr12Ni9Mo4Cu2, heat treatment experiment, hardness measurement, optical microscopy observation, scanning electronic microscopy and energy diffraction analysis was used to investigate the effect of different aging process on the mechanical properties and the microstructures of the maraging steel 00Cr12Ni9Mo4Cu2. The results show that: the hardness of the 00Cr12Ni9Mo4Cu2 steel increases very rapidly with the holding time in the aging process when the holding time is less than 0.5 h at 475 ℃. After that, the hardness increases slightly with the holding time. The material has a strength higher than 2200 MPa when it is aged at 475 ℃ for 2h, additional 1000 MPa higher than that of the as-received material. This additional increasing in the strength of the steel after aging is attributed to the precipitation of the dispersed quasi-crystalline particle sizing in tens of nano-meters. A treatment at 550 ℃ would lead to a slight decreasing in the strength of the material as compared with that treated at 475 ℃, for the decomposition of the maraging precipitates. It is concluded that the steel aged at 475 ℃ has a high hardness and a relatively high plasticity which is suitable for the industry applications under the complicated stress. The results should be helpful to the materialists for the developing and application of the ultra-high strength steel. [ABSTRACT FROM AUTHOR]

Yan’an Formation groundwater is an important underground drinking aquifer in the Shendong mining area,and the level of its F-content directly affects the safety of drinking water and the surrounding ecological environment. However,the characteristics of F-content,spatial distribution and formation mechanism in groundwater of the Yan’an Formation in this region have received little attention. The project team systematically collected 30 groups of Yan’an Formation groundwater in August-September 2020,and explored the characteristics of F-content,spatial distribution and formation mechanism in Yan’an Formation groundwater in terms of mineral dissolution and precipitation,evaporation,cation exchange,competitive adsorption and anthropogenic pollution effects by using Piper diagram,correlation analysis,PHREEQC simulation,etc. The results showed that the concentration of F-in groundwater of the Yan’an Formation in the Shendong mining area ranged from ND to 17. 60 mg / L,with an average value of 4. 55 mg / L. Compared with the national sanitary standard for domestic drinking water （GB 5749—2006） （1. 0 mg / L）,73. 3% of the samples exceeded the standard. High TDS,Cl-,HCO3-,Na+and low Ca2+and Mg2+water environment are favorable for F-enrichment,and Na-HCO3type,Na-HCO3-Cl type and Na-HCO3-SO4type are the main hydrochemical types of high fluoride water. Fluoride-bearing mineral dissolution is an important source of groundwater F-in the Yan’an Formation. The salt effect under evaporite dissolution and silicate weathering reduces the solubility of fluoride-bearing minerals and promotes the dissolution of F; cation exchange further accelerates the dissolution of fluoride-bearing minerals through sodium-calcium transfer,adsorbed state fluorine under competitive adsorption also provides an additional source of groundwater F-. However,the effects of evaporation and human activities on the elevated F-content of groundwater in the Yan’an Formation are small and negligible. The results provide a scientific basis for the safety of water quality for local drinking water and sustainable development of ecological environment. [ABSTRACT FROM AUTHOR]

There are many problems in urban built-up areas, such as site limitation, ground hardening, complex interference, etc. Therefore, higher requirements are put forward for the site adaptability, anti-interference ability and detection resolution of urban geophysical prospecting methods. The shallow fine detection work of a seafood wholesale market in Chengdu was taken as an example. The short polar distance “T”/“L”-type composited observation array was flexibly arranged in the narrow space between dense buildings on the surface. High quality surface wave dispersion data of 50～10 Hz frequency band were obtained through extended spatial auto correlation（ESPAC） algorithm, the S-wave velocity profile obtained by inversion meets the requirements of fine stratification of 2～40 m buried depth, which effectively supports the construction of a subway track in Chengdu. The comprehensive research results and drilling data show that the “smart small array” and ESPAC algorithm can replace the previous working mode that requires additional active sources to supplement the high-frequency signals when detecting the shallow strata. It can not only save the construction cost, but also avoid the noise, vibration and other disturbance caused by heavy hammer. It has certain application value in the field of urban geophysical exploration. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Technology Economics is the property of Chinese Society of Technology Economics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to obtain the fatigue life of aeroengine turbine rotor blades, orthogonal load decoupling combined loading was realized by electromagnetic induction heating and high-low cycle composite load coordinated loading control method. The coupling responses of rotor blades under high temperature environment, low cycle centrifugal load and high cycle vibration load were studied, and the above technology were verified based on turbine blade simulation test pieces. The results show that the test technology is feasible and correct. It can be seen that this technology can realize multi field coupling complex load strength test loading of aeroengine structural components. [ABSTRACT FROM AUTHOR]

In order to quantitatively analyze the degree of fusion of old and new asphalt in thermal regeneration, Fourier transform infrared spectroscopy (FTIR) was used to analyze the fusion degree of recycled asphalt pavement (RAP) to study the degree of fusion of old and new asphalt during thermal regeneration. According to the different infrared characteristic peaks of styreneic-block copolymers (SBS) and base asphalt, using SBS as asphalt tracer, a method for quantitative analysis of the degree of fusion between old and new asphalt was proposed based on the layered solution method. The effect of mixing temperature, mixing time and lignin fiber on the fusion degree of new and old asphalt in the thermal regeneration process was studied by this method. The results show that with the increase of mixing temperature and mixing time, the degree of fusion between old and new asphalt also increases, and the addition of lignin fiber also improves the degree of fusion between old and new asphalt. [ABSTRACT FROM AUTHOR]