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[Objective] To delve deeper into the spatiotemporal characteristics and pivotal driving factors underlying the hardness of black soil in eroded sloping farmlands. [Methods] Based on the dynamic monitoring of soil penetration resistance across 110 sample points in typical water erosion sloping farmlands, coupled with measurements of pertinent factors, the factors affecting soil penetration resistance were analyzed by multivariate linear regression (MLR) and random forest (RFR) models, and its transfer function was further construct. [Results] The spatiotemporal variability of soil penetration resistance was influenced by a combination of soil depth, moisture conditions, and agricultural practices. Notably, the spatial heterogeneity was significantly lower in the topsoil layer compared to the sub-surface layer, with coefficients of variation of 17.4% and 26.3%, respectively. As the soil dried out and the duration since the last tillage increases, spatial heterogeneity tended to intensify. Soil erosion played a significant role, with higher soil penetration resistance observed in areas of intense erosion compared to deposition zones, particularly under wet conditions where the difference is most pronounced (p

The conventional petroleum field in Jiyang Depression has always been the main battlefield of exploration and development in Shengli Oilfield. It has experienced more than 60 years of exploration and development and entered the mature exploration stage as a whole， but it still has a relatively large scale of reserve increase every year， which is not consistent with the traditional growth trend of proven petroleum-in-place in oil and gas-bearing basins. The critical issues concerning the exploration decisions of Shengli Oilfield need to be clarified urgently， including the growth law of the conventional proven petroleum-in-place in Jiyang Depression， the strong trend of reserve increase， and the main fields for reserve increase. By analyzing the exploration process of Jiyang Depression， the geological characteristics， resource conditions， exploration investment， theory and technology， resource sequence， and other exploration elements were analyzed， revealing the exploration discovery law of conventional petroleum in Jiyang Depression. The broom-shaped model prediction method and proven rate method of resource were used to predict the growth trend of conventional proven petroleum-in-place. The scale and favorable direction of future reserve increase of conventional petroleum in Jiyang Depression were clarified by analyzing the main fields with reserve increase. The results show that the complex geological characteristics of Jiyang Depression and the relatively abundant remaining resources determine the diversity of exploration objects， the tortuosity of the exploration process， and the long-term nature of exploration history. The conventional petroleum in Jiyang Depression can still maintain a long period of stable reserve increase under conditions of ensuring a relatively stable exploration investment， continuing to innovate the exploration theory and key technologies， and maintaining a relatively reasonable resource sequence. Jiyang Depression can still produce about 2.5 × 108 t of conventional proven petroleum-in-place in the next 10 years under the current economic and technical conditions and the relative guarantee of exploration investment. It is pointed out that the Neogene river sandstone reservoir， lithologic oil and gas reservoirs in the Upper Submember of the 4th Member of the Eocene Shahejie Formation（Es4U）-the Lower 3rd Member of the Eocene Shahejie Formation（Es3L）， and other mature fields are still the ballast stones for stable reserve increase. Kongdian Formation-the deep field of the Lower Submember of the 4th Member of the Eocene Shahejie Formation（Es4L） is an essential field for large-scale reserve increase， and the pre-Paleogene buried hill is a favorable direction for the petroleum enrichment and high yield. In the future， the exploration progress in the unconventional and new energy fields should be closely tracked， and the research results of the growth law and the reserve increase trend of conventional proven petroleum-in-place in Jiyang Depression should be constantly improved and revised to make them more conform to the development trend of oilfield exploration and guide the oilfield exploration decisions.

Objective Vehicle base serves as a place for parking and maintenance of guideway rubber-tyred trams. Vehicles are traveling on complex routes and operating turn-back frequently within the base. Since guideway rubber-tyred trams turn-back operation in vehicle base will undermine the vehicle turnover efficiency, a vehicle base layout form that can avoid tram turn-back operation is proposed. Method The characteristics of guideway rubber-tyred tram vehicles and turnouts are introduced. The current production process and existing problems of guideway rubber-tyred tram vehicle base in China are analyzed. Combining the advantage of vehicle small turning radius and the vehicle base site selection conditions, vehicle base schemes are analyzed. A design scheme for rubber-tyred tram vehicle base without turn-back operation is developed, as well as the implementation process for scheduling vehicles without turn-back operation. When the washing garage for daily inspection is not occupied, the daily inspection, washing, and parking process will be adopted; when it is occupied, the process with a designated parking space, daily inspection, washing, and corresponding parking are used. In the latter process, simultaneous dispatching of two vehicles is adopted to avoid vehicle turn-back operation. The advantages and disadvantages of the vehicle base scheme are analyzed, and the conditions for setting up a vehicle base that meets the requirements of no turn-back operation are put forward. Result & Conclusion The proposed vehicle base without turn-back operation is implemented in a testing line project in China, and is expected to achieve certain results in improving vehicle turnover efficiency, reducing personnel count in vehicle base, and saving land.

[Objective] This study aimed to clarity the role of sedimentation and erosion in shaping the spatial pattern of soil quality in black soil slope croplands. [Methods] Taking the sloping farmland in typical water-eroded areas in northeast China as the research object, we used the soil attributes of 110 sample points and the soil quality index (SQI) index based on the minimum data set to evaluate the spatial differentiation characteristics of soil quality at the slope scale, while the effects of slope gradient, slope position, and soil depth were determined using generalized linear models (GLMs). [Results] (1) Opposing patterns of soil nutrient content and spatial characteristics were observed between the surface and subsurface layers in sloping croplands. Most nutrient indicators exhibited significantly higher content in the tillage layer compared to the subsurface layer. However, the surface layer showed lower spatial heterogeneity and weaker correlation with related physicochemical indexes comparing with the subsurface layer (p0.05). (3) Soil depth, slope position, and slope gradient emerged as key factors influencing the variability of SQI in slope croplands. The GLM results demonstrated that, for the same soil horizon, slope, aspect, and their interactions explained over 95% variation in SQI. Among them, the explanatory degree of slope position was 68%, and that of slope gradient was 22%. Considering the factor of soil depth, the explanatory degrees of soil depth, slope position, and slope gradient on the variation of SQI in the range of 0—40 cm were 39%, 31%, and 10%, respectively. [Conclusion] The combined method of SQI and GLM was used to clarify the shaping role of the erosion-sedimentation process in the spatial differentiation of black soil quality in sloping cropland, and the research results can provide technical support for the evaluation and management of the quality of eroded and degraded black soil in typical water-eroded areas.

We present a novel approach for actively controlling electromagnetically induced transparency (EIT) analogs in a single-mode microstrip cavity. This cavity is side-coupled with a pair of varactor-loaded split-ring resonators (SRRs). The EIT-like effect is achieved through resonance hybridization between the paired SRRs with frequency detuning. The microstrip cavity is utilized to enhance the EIT-like transmission properties, including Q-factor and group delay. Varactor diodes, soldered at the gap of the SRRs, are biased electrically through a DC voltage source. This dynamic modulation setup allows for the tuning of the enhanced EIT analog. Experimental results demonstrate that the enhanced EIT-like transmission spectrum can be tuned reversibly by 378 MHz with respect to the transmission dip frequency of 2.464 GHz under the bias voltage ranging from 0 to 5 V. Simultaneously, the controlled transmission spectrum enables a remarkable change in group delay of 10.9 ns. Moreover, the modulation amplitude of the composite SRRs-cavity structure reaches a peak value of up to 34.5 dB, significantly higher than the 6.4 dB of the individual SRRs pair. These results hold promise for inspiring innovation in actively controlled photonic devices for practical applications. [ABSTRACT FROM AUTHOR]