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Elevated temperatures have a substantial influence on the properties of the materials used in concrete manufacturing, leading to a noticeable decrease in the strength properties of the concrete. Attaining the intended compressive strength of concrete is a demanding and time-consuming pursuit. However, the use of supervised machine learning methods allows for an accurate initial prediction of the intended result. This work demonstrates the utilization of multi-layered perceptron (MLP), support vector regression (SVR), and least squared SVR (LSSVR) for predicting the compressive strength of concrete at elevated temperatures. The prediction models were enhanced by using the reptile search algorithm (RSA) and were trained on a dataset consisting of 207 data points. The investigation included a collection of nine input variables, namely water, cement, coarse aggregate, fine aggregate, fly ash, superplasticizers, silica fume, nano silica, and temperature. The results indicate that all the LSSR, SVRR and MLPR show great potential in accurately predicting the fcof concrete at elevated temperatures with acceptable values of the R2. Regarding the values related to the error-based metrics, the lowest values belonged to the LSSR model with a decline of about 50% with respect to the SVRR and MLPR networks. Turning to uncertainty analysis, it was obvious that in all three training, validating, and testing phases, MLPR resulted in the highest values of uncertainty, compared to SVRR. On the other hand, the most reliable model called LSSR introduced the smallest values of uncertainty at 6.028, 5.98, and 6.52, respectively, which depicted remarkable accuracy and dependability.

Despite the great potential of CRISPR-based detection, it has not been competitive with other market diagnostics for on-site and in-home testing. Here we dissect the rate-limiting factors that undermine the performance of Cas12b- and Cas13a-mediated detection. In one-pot testing, Cas12b interferes with loop-mediated isothermal amplification by binding to and cleaving the amplicon, while Cas13a directly degrades the viral RNA, reducing its amplification. We found that the protospacer-adjacent motif-interacting domain engineered Cas12b accelerated one-pot testing with 10–10,000-fold improved sensitivity, and detected 85 out of 85 SARS-CoV-2 clinical samples with a sensitivity of 0.5 cp μl−1, making it superior to wild-type Cas12b. In parallel, by diminishing the interference of Cas13a with viral RNA, the optimized Cas13a-based assay detected 86 out of 87 SARS-CoV-2 clinical samples at room temperature in 30 min with a sensitivity of 0.5 cp μl−1. The relaxed reaction conditions and improved performance of CRISPR-based assays make them competitive for widespread use in pathogen detection.

Geotechnical engineering places a high priority on accurately predicting the soil pile-bearing capacity (Pu). Machine learning (ML) must be crucial to achieving this precision. A ground-breaking method combines the adaptable Decision Tree (DT) technique with cutting-edge optimization algorithms like Tasmanian Devil Optimization (TDO) and Gold Rush Optimizer (GRO). This fusion produces three distinct models: DTTD, DTGR, and a hybrid DT model. DT, which is renowned for its ability to capture complex non-linear relationships between input variables and soil Pu, is at the center of this predictive framework. The effectiveness of DT, however, depends on accurate hyperparameter tuning and the choice of a suitable optimization approach, which is precisely where TDO and GRO come into play. GRO strategically modifies hyperparameters to simulate the development and dispersal of dandelion seeds, improving the DT’s ability to predict the future. On the other hand, TDO uses the crystalline atomic structure as inspiration to optimize DT parameters precisely. The power of DT and these state-of-the-art optimization methods are combined in this synergy to produce three distinctive models. DTTD stands out among these models as the top performer, with an exceptional R2value of 0.996, indicating an excellent fit for the data. Additionally, it has the lowest RMSE, which stands at 23.221, and highlights its unmatched predictive accuracy. Thus, the DTTD model represents a novel and highly successful strategy for precisely forecasting soil Pu.

This paper presents a groundbreaking method for predicting the compressive strength (Fc) of recycled aggregate concrete (RAC) through the application of K-nearest neighbors (KNN) analysis. The task of designing mixture proportions to achieve the desired Fccan be remarkably intricate, owing to the intricate interplay among the components involved. Machine learning (ML) algorithms have exhibited considerable promise in tackling this complexity effectively. In pursuit of enhanced prediction accuracy, this research introduces a semi-empirical approach that seamlessly integrates strategies, including optimization techniques. This study incorporates two meta-heuristic methods, the Fire Hawk optimizer (FHO) and Runge–Kutta optimization (RUK) to enhance model accuracy. The research results reveal three separate models: KNFH, KNRK, and a single KNN model, each providing valuable insights for precise Fcprediction. Remarkably, the KNFH model stands out as a top performer, boasting an impressive R2value of 0.994 and a meager RMSE value of 1.122. These findings not only validate the accuracy and reliability of the KNFH model but also highlight its effectiveness in predicting Fcoutcomes. This approach holds great promise for precise Fcforecasting in the construction industry. Integrating meta-heuristic algorithms significantly improves model accuracy, leading to more reliable forecasts with profound implications for construction projects and their outcomes. This research marks a significant advancement in predicting Fcusing ML, offering valuable tools for engineers and builders.

Seabed fluid escape is active in the Makran subduction zone, Arabian Sea. Based on the new high-resolution 2D seismic data, acoustic blanking zones and seafloor mounds are identified. Acoustic blanking zones include three kinds of geometries: Bell-shaped, vertically columnar and tilted zones. The bell-shaped blanking zone is characterized by weak and discontinuous reflections in the interior and up-bending reflections on the top, interpreted as gas chimneys. Vertically columnar blanking zone is interpreted as side-imaged gas chimneys associated with focused fluid flow and topped by a seafloor anomaly expressed as a localized reflection discontinuity, which may together serve as a vent structure. Tilted acoustic blanking zone could be induced by accretionary thrust activity and rapid sedimentation surrounding slope. Seafloor mounds occur at the sites of bell-shaped acoustic blanking zone and may be associated with the material intrusion. Bottom simulating refectors (BSRs) are widely distributed and exhibit a series of characteristics including diminished amplitude, low continuity as well as local shoaling overlapping with these acoustic blanking zones. The large amount of gases dissociated from the gas hydrates migrated upwards and then arrived at the near-seafloor sediments, followed by the formation of the gas hydrates and hence the seafloor mound.

AbstractFocused on the pressure of transportation resource and the increasing traffic demand, this paper starts from the classification of urban transportation system, making use of communication technology, information technology and computer technology, etc., analyzing the feasibility of the project based on urban intelligent transportation management system, and putting forward the study and design of urban intelligent transportation management system, pointing out the improvements on intelligent processing of transportation information, systematic control theory, application and performance of urban intelligent transportation management system.

Grazing by large herbivores may have a strong impact on plant diversity and productivity, but the effects are expected to vary with grazing pressure. The changes in productivity and species diversity of Stipa purpurea-dominated semi-arid alpine steppe grassland were measured under four different stocking rates of Tibetan sheep [no grazing, light (2.4 sheep units ha-1), moderate (3.6 sheep units ha-1), and heavy (6.0 sheep units ha-1) grazing] in a 5-year (2006–2010) grazing experiment on the Qinghai-Tibetan Plateau, China. Herbage mass and aboveground net primary productivity of alpine steppe declined significantly with increasing stocking rate (P<0.05). Over the 5 years of the experiment, the proportion of forbs and sedges increased significantly under light and moderate grazing; the proportion of grasses decreased significantly, whereas the proportion of S. purpurea did not change compared with the no grazing treatment. Species diversity was highest under moderate grazing and was significantly higher than the no grazing treatment in 2 years (2008 and 2010). Moderate grazing enhanced the species diversity of the plant community due to an increase in the proportion of forbs. There were significant positive linear correlations between herbage mass and species diversity under no and light grazing. Species diversity was not related to productivity under moderate and heavy grazing. In conclusion, grazing by sheep reduced plant productivity; plant diversity increased under low and moderate grazing, and was as a result of changes in the composition of the plant community of a semi-arid alpine steppe.

The theoretical solution of the transient response of the wind-induced internal pressure based on assuming the external pressure is simple harmonic excitation by the linear equation governing the dynamics of internal pressure was presented. The effect of orifice loss coefficient, opening angle, the opening ratio and background porosity factor (Pf) on the transient internal pressure character was analyzed. The result shows: the peak value of the transient internal pressure and the overshooting ratio decreases with the increase of the orifice loss coefficient; the opening angle decides the overshooting effect. The overshooting ratio increases with the opening ratio and presents a decreasing trend while Pf increases; the effect of these factors on steady internal pressure is relatively small.

In response to the estimation of the peak values of wind pressure on the maintenance structure, the results with TTU low-rise building standard model of different methods are analyzed and compared. The results show: the results of peak-to-average method and Cook & Mayne method are very close for the long sample estimation of the peak values of wind pressure, the former is the most ideal method for estimation of extreme wind pressure; For short sample estimation, the peak-to-average method fails because the sampling is not long enough, but the Cook & Mayne method can estimate accurate peak value of wind pressure by the short sample (the corresponding prototype time not less than 600s); The peak factor method based on the assumption of normal distribution is not applicable to low-rise building and the results are relatively dangerous.

The high strength stainless steel wire mesh and high-performance mortar reinforcement has been gradually applied in construction, bridge reinforcement project. Study of the reinforcement at home and abroad mainly focus on research of strengthening RC beam shear, bending, and seismic performance. Although the application of RC column has already been carried out, there is also a short of basic technical an applied research for further study. After looking through a large amount of references, this article gives a summary of the present study about reinforcing RC column with the reinforcement, draws some conclusions and predicts the prospect of development.

Klebsiella pneumoniaeinvasion syndrome (KPIS) is a critical multi-site infection that is usually caused by highly virulent Klebsiella pneumonia. It is relatively common in Asian patients with diabetes and leads to sepsis, which has a high mortality rate. We report the case of a man in his early 40s who presented to the hospital with blurred vision in his left eye of 7 days’ duration and fever of 1 day’s duration. After a complete examination, he was diagnosed with KPIS on the basis of his liver abscessation, lung abscessation, endophthalmitis of the left eye and brain abscessation. After needle puncture and drainage of the left eye and liver abscess and anti-bacterial treatment with meropenem, the patient recovered well. When KPIS is suspected, attention should be paid to the sites of infection and the selection of the most appropriate antibiotics, but the most important aim should be to drain the lesions in a timely manner to improve the patient’s prognosis.

The objective of this study was to investigate the effects of rat umbilical cord mesenchymal stem cells (UCMSCs) from Wharton’s jelly on dibutyltin dichloride (DBTC)–induced chronic pancreatitis (CP) and subsequent pancreatic fibrosis in rats.

A novel silver nanocluster is synthesized using a DNA template with short guanine at the 3′-end of a DNA scaffold to enhance the fluorescence intensity. The obtained DNA-stabilized silver nanoclusters (G-DNA-Ag NCs) are found to exhibit a strong red fluorescence at 605 nm and its fluorescence can be sensitively quenched by H2O2. This allows us to develop a new enzymatic method for fluorescent detection of cholesterol through oxidation by cholesterol oxidase which can generate H2O2. The present method is convenient without the need for complicated operations, and demonstrates desirable selectivity with no interferences from species such as ascorbic acid, glucose and urea. It shows a linear detection range for cholesterol from 0.2 to 200 μM with a detection limit of 0.15 μM.

This study presents the numerical investigation of the low-velocity impact for the foam-cored sandwich composites. Firstly, the proposed FEA model is validated by comparing the results between simulation and test. The user subroutine VUMAT and the crushable foam model are chosen to describe the damage of the face sheets and the characteristics of the foam material, respectively. The detailed damage process of the sheets and the foam is clearly shown. The sensitivity of seven parameters related to foam-core material are studied. It is shown that the yield strength, the fracture strain and the fracture displacement have significant effects on the impact-resistance of the foam-cored sandwich composites.

The magnetic circuit of MR damper was given,Finite Element Analysis and the structure optimization of MR damper were reserched.The theory of a variable domain by adopting an adaptive algorithm based on fuzzy-control was applied in semi-active suspension control with MR damper.The adaptive law for membership functiongs was designed for input and output.Based on 2DOF 1/4 car model with the simulationed for road protile as random input,the control simulation of MR semi-actibe suspension was carried out,results show that spring mass acceleration reduced while an adaptive algorithim with a variable domain fuzzy control was used to compare with ordinary strategy,the riding comfort got improved.

This thesis analysis the work course of the system, the match of major part, a fuzzy method for controlling the engine coolant temperature is proposed. The fuzzy rule base is correspondingly established based on the experimental data. The control query table is created through computing and analyzing via the fuzzy logic tools in MATLAB. The test indicates that only a little improvement of the current engine cooling system can better solve the problem that it is difficult to accurately control the engine coolant temperature.

In order to make the material removal distribution on polishing silicon surface more non-uniform during the chemical mechanical polishing (CMP), a kind of the bionic polishing pad with phyllotactic pattern has been designed based on phyllotaxis theory, and by polishing experiment, the effects of the phyllotaxis parameters on material removal distributions on silicon wafer surfaces are investigated. The research results show that the material removal distribution of polishing silicon surface more uniform and the edge rounding of polishing wafer can be decreased when the phyllotaxis parameters of the polishing pad are reasonably selected.

In order to make the polishing slurry distribution more uniform over the polishing region, a new kind of polishing pad, which has sunflower seed pattern, has been designed based on the phyllotaxis theory of biology, and the boundary conditions of polishing slurry flow have been established. By the help of computational fluid dynamics software (FLUENT), the flow state of the polishing slurry is simulated and the effects of the phyllotactic parameters of polishing pad on the flow field of polishing slurry are analyzed. The results show that when the polishing slurry is imported from the center of phyllotaxis polishing pad, the slurry flows along the counterclockwise and clockwise spiral grooves of phyllotatic pattern, which make fluid flow divergence around, and the flow field becomes more uniform.

In this paper, a new welding experiment is studied by applying an additional longitudinal electromagnetic field to CO2 welding process (abbr. LEM-CO2 welding).The characteristics of droplet transfer, macrostructure and microstructure are compared between LEM- CO2 welding and general CO2 welding on Q235 low carbon steel thick plate joint. The research results shows that, an additional longitudinal magnetic field can have a significant effect on properties of the droplet transfer in CO2 welding, the frequency and stability of the droplet transfer in LEM-CO2 welding are improved. The grains of welding seam are refined and welding joints has a higher quality. So the additional longitudinal magnetic field is a very simple and effective method to improve the properties of CO2 welding thick plate joint.

The anisotropic thermopower of Tl2Ba2CaCu2O8 single crystals has been measured. The room temperature value of Sab is about 14 mV/K. With the decrease of temperature Sab increases linearly in a speed of (0.06 ÷ 0.065) mV/K2 down to about 160 K below which Sab flattens off and drops to zero at Tc. Sc at room temperature is around 30 mV/K and only weakly depends on temperature. The superconducting transition determined by thermopower measurements shows that the transition along the c-axis is always lower than that in the (a, b)-plane.

In order to directly indicate the change of the quality of temperature sensitive products, such as food and medicine, during transportation and storage, the time-temperature indicator (TTI) was researched. It has cumulative effect on the time and temperature in the transport process and also can be used to monitor the environmental temperature changes. Based on the novel glucose oxidase and horseradish peroxidase double enzyme reaction system, a new time-temperature indicator was developed. The suitable storage conditions and the composition of double enzyme asof the TTI reaction system were studied. In conclusion, the time-temperature indicator with obvious color change is applied to the packaging of cold products during the transportation and storage process.

Time-temperature indicator has been widely applied in the food industry. And, the theoretical study shows that if the time-temperature indicator is applied to monitor food, the activation energy of TTI temperature-dependent must be consistent with the activation energy of food quality loss. In this study, kinetics of absorbance and color changes in bi-enzyme were investigated as a function of storage temperature. Absorbance value was used to evaluate the enzyme reaction process under different temperature. Color change was evaluated in terms of the total color difference (DE). The results indicated that the time - temperature dependence of Absorbance and DE values followed a zero-order model. The Arrhenius equation adequately described the temperature dependence of the reaction rate constants for both absorbance and color parameters, respectively, from which the activation energies and rate constant at different temperature were obtained. There were significant linear correlations between absorbance, color and time parameter.