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The proportion of the car is one of the important parts of car styling design. The study of the car proportion is of great significance. The proportion of the car is determined by the technical conditions, functions and aesthetics. At present, there're not many studies on the area proportion of the car .There're studies on the line relationship and length, width, height proportion of the car. This paper uses computer image processing method to calculate the projected area proportion of the hatchback car. And it provides a new thinking and method for the car proportion study. The result shows that the projected area proportion values of the hatchback cars of European, American, Japanese, Korean and Chinese series on the market have a difference, but are close. And the total average projected area proportion values of car window and car body of the hatchbacks have been calculated.

Most existing clustering algorithms suffer from the computation of similarity function and the representation of each object. In this paper, we propose a clustering tracker based on region proposal network (RPN-C) to do tracking by clustering anchors output by region proposal network into potential centers. We first cut off the second part of Faster RCNN and then cast clustering algorithms in feature space of anchors, including K-Means, mean shift and density peak clustering strategy in terms of anchors’ centroid and scale information. Without fully connected layers, the RPN-C tracker can lower the computational cost up to 60% and still, it can effectively maintain an accurate prediction for the localization in next frame. To evaluate the robustness of this tracker, we establish a dataset containing over 2000 training images and 7 testing sequences of 8 kinds of fruits. The experimental results on our own datasets demonstrate that the proposed tracker performs excellently both in location of object and the decision of scale and has a strong advantage of stability in the context of occlusion and complicated background.

Hot-in-place recycling of asphalt pavement is one of the important regeneration technologies of pavement engineering, which apply to the pavements with fewer diseases, excellent driving quality, slight rutting, and good pavement structural strength. However, the surface layer of some road sections was aging, the penetration index of aged asphalt at 25°C is lower than 20(0.1mm), which does not meet the recommended requirements of the criterion in China. In 2019, 3 sections of test projects were laid on the expressway, each section was 1 km, for confirming the feasibility of using hot-in-place recycling with asphalt penetration less than 20 (0.1mm) through physical engineering. Experimental results confirmed that Marshall stability, residual stability, dynamic stability and water seepage of the hot-in-place recycled mixture optimized by the recycled pavement material with a penetration of aged asphalt of 15 can meet the specification requirements, Pavement Condition Index (PCI), International Roughness Index (IRI), and Rut Depth (RD) of the test pavements are in good conditions.

Cultural self-confidence and the going-global strategy of China’s excellent traditional culture have given red culture new opportunities and higher expectations, accelerating red culture to go abroad following the times. Based on the overview of the development of red tourism, the article clarifies the present situation of red tourism international publicity in Gannan through SWOT, believes that the challenges and opportunities of red tourism in Gannan coexist, and further proposes several paths including updating the concept while telling a good story, clarifying the audience while accumulating talents, refining the spirit while upgrading technology, innovating channels while combining the internal and external, “casting the soul” with culture by joint cooperation, and enriching the routes besides “red and green”. The foundation is laid for the continuation of red resources to open a new chapter in the era.

The finite volume discrete solution of the Navier-Stokes equation and the RNG model of the turbulence model are used to numerically simulate the flow and heat transfer characteristics of supercritical kerosene in a circular tube. The results show that as the inlet mass flow increases, the wall surface temperature and the central flow oil temperature gradually decrease, and the pressure loss becomes larger. As the inlet temperature increases, the wall surface temperature and the central flow oil temperature both increase. When the heat flux density is constant, as the pressure increases, the deterioration of heat transfer will be weakened, and increasing the pressure can improve the effect of convection heat transfer.

This paper presents a CFD simulation analysis method for the regenerative cooling channel of a supercombustion ramjet engine, and performs three-dimensional modeling and analysis. The influences of inlet mass flow, inlet pressure, and inlet temperature on the flow and heat transfer characteristics of kerosene in the cooling channel were analyzed, and the conclusions are as follows: The larger the inlet mass flow, the lower the maximum wall temperature and oil temperature. The change trend of wall temperature is basically the same under different inlet pressure conditions, all of which increase violently first, then stabilize and then suddenly increase suddenly, then decrease almost to the outlet, and the temperature is almost the same under different conditions.As the inlet temperature decreases, the temperature difference between the wall surface and kerosene becomes larger, and the convective heat transfer coefficient gradually increases.

Pulses crops are widely distributed in China, but mechanization production-level of this crops is relatively low at present. So, a special nail-tooth thresher for pulses crops was carried out in this project to solve the problem of mechanical threshing. The roller diameter, speed, length, and nail-tooth structure, stripper concave screen, power device and cleaning system are determined by detailed theoretical calculation. Testing result of the trial-production prototype showed that the threshing roller with large diameter and low rotating speed, the nail-tooth threshing mechanism and the concave plate screen with large spacing are suitable for the broad bean thresher. The optimal combination is roller speed 400 /min, feed quantity 1.2 kg/s and concave tolerance 54 mm. Testing results showed that impurity content and breaking rate of the developed nail-tooth type broad bean thresher were respectively 1.09 %and 3.45%, It could improve the efficiency of the pulses crops threshing process significantly.

An ultra performance liquid chromatography – electrospray ionization triple-quadruple tandem mass spectrometric(UPLC–ESI MS /MS) method was developed for determining Quinololine antibiotics (Carbadox,, Quinocetone, Mequindox, Olaquindox, Cyadox, Tilmicosin, Tylosin, quinoxaline-2-carboxylic acid, 3-methylquinoxaline-2-carboxylic acid) and aminoglycoside antibiotics(Tilmicosin, Tylosin) residues in Penaeus. vannamei, Samples were extracted with acidified acetonitrile, then cleaned up with hexane. The separation of targets was carried out on a Waters BEH C18 column using acetonitrile and 0. 1% fomicacid as mobile phase. Analyte identification and quantification were performed by MS/MS under multiple-reaction monitering(MRM) mode with the external standard method. The results showed that there were good linear relationships between peak area and concentrations of nine targets in the range of 2.5 ~ 50 μg/L, with correlation coefficients more than 0. 999 and The limits of detection(LOD) were in the range of 0. 1 ~ 0.9 μg/kg. the recoveries ranged from 80.2% ~ 94.0%, with RSDs of 1.7%~8.4%. The method is simple, accurate and precise, and It could satisfy the requirement of mass and fast analysis in the laborator.

In the recovery of low permeability reservoir, the capillary pressure has an important effect, which may reduce gas production. Due to the capillary end effect, there are two flow patterns in the vicinity of the production well: both water and gas phases can flow into the production well and only gas phase can enter the production well. Based on the analytical equations of one-dimensional radial flow considering the capillary end effect, an alternative numerical well model for low permeability gas reservoir is constructed. Numerical examples show that the proposed model can reflect the dramatic change for saturation and gas-phase pressure in the vicinity of the production well both for two flow patterns, and therefore can predict the gas and water productions accurately at different grid scales. In contrast, the original Peaceman well model for multi-phase flow, which is directly extended from that for single-phase flow, only can provide good prediction under the condition of that the grid size is enough small. Especially, for the original Peaceman well model, this problem is out of control since it is difficult to estimate a suitable grid size.

Supply chain management is important for coal companies and organizations to improve their business and enhance competitiveness in the Chinese marketplace. The bullwhip effect problem of coal supply chain systems with all demands, lead times, and ordering quantities in an uncertain environment is addressed in this paper. To simulate the bullwhip effect, the Hong Fuzzy Time Series approach and Genetic Algorithm module are preferred as a superior forecasting model. And then a back propagation Neural Network module is added to defuzzify the output of the proposed model. So the bullwhip effect is calculated and analyzed here. The effectiveness and flexibility of proposed method is verified through simulation study.