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With the development of multi electric/all electric aircraft, the degree of aircraft secondary energy electrification is becoming higher and higher. As the core component of the electrical system, the motor presents the trend of small volume and high-power density. The heat dissipation problem of compact motor is becoming more and more serious. At present, the self-driven fan cooling system is widely used in aircraft motors. In this paper, the axial fan cooling system of an aero generator is taken as the research object, and the changes of fan flow field and aerodynamic characteristics in the fan motor coupling model of the isolated fan and the installed motor are analyzed by using three-dimensional computational fluid simulation. At the same time, the influence of the change of the axial distance between the fan and the motor on the aerodynamic performance is also studied. The analysis of the simulation results shows that the close coupling between the motor and the fan components greatly affects the flow structure in the fan, resulting in the distortion potential effect on the fan outlet section. The fan flow field appears the blade root reflux, the channel vortex in the blade and the expansion of the corner separation area. With the increase of the axial distance between the motor and the fan, the influence of the motor on the flow in the fan gradually approaches the flow blocking effect.

With the development of the times, traditional innovation and entrepreneurship education exist in the backwardness of education concept and learning concept. This paper proposes a model for entrepreneurship innovation that incorporates multi-source data fusion technology. From both online and offline sources, we obtain multi-source data about the education and teaching methods of the entrepreneurship innovation education concept in higher vocational colleges and universities. In the process of multi-source data fusion, data is preprocessed to improve its quality and efficiency during data fusion. Using the least squares method to complete the multi-source data fusion operation, combined with the concept of entrepreneurship innovation education, co-designed a data fusion-driven innovative entrepreneurship education teaching model that integrates interactive and targeted teaching methods. The model underwent validation and analysis. The data show that after some time of adopting the targeted teaching method to teach students innovative and entrepreneurial concepts, the difference between the mean value of the level of creative and entrepreneurial concepts of the students in the experimental group mean value (43.79) and the control group mean value (43.79) is 4.55. The sig value is 0.019

In order to improve the small intestinal digestibility of rice analogues (RA) and to enhance the nutritional value of the product, rice and potato flour blends were used as raw materials to prepare RA by direct extrusion modification using chemical or biological modifiers combined with high-temperature puffing. The internal structure and nutritional characteristics of RA were analyzed. The results showed that potato starch and amylase enhanced the digestive resistance of RA. The tested chemical modifiers mainly affected the structure and physicochemical properties of starch, in turn increasing the apparent viscosity and decreasing the degree of hydrolysis and digestibility of RA. Octenylsuccinic anhydride (OSA) played a promoting role in the initial stage of intestinal digestion. Propylene oxide (HPPO) reduced the particle size and increased the storage modulus (G’) of RA. Sodium trimetaphosphate (STMP) increased the particle size and G’ of RA. α-Amylase promoted the decomposition of large particles, led to even distribution of proteins on the surface of particles, and inhibited digestion. High-temperature expansion promoted starch decomposition in the early stage of intestinal digestion. Digestion results showed that the combinatorial effect of extrusion modification and high-temperature puffing weakened the film-forming capability of potato starch, which effectively inhibited the decomposition of the starch and weakened the digestive reaction when it just entered the intestine.

As the reliability and lifespan requirements of modern equipment continues to escalate, the problems with very high cycle fatigue (VHCF) has obtained increasingly widespread attention, becoming a hot topic in fatigue research. Titanium alloys, which are the most extensively used metal materials in the modern aerospace industry, are particularly prone to VHCF issues. The present study systematically reviewed and summarized the latest (since 2010) developments in VHCF research on titanium alloy, with special focus on the (i) experimental methods, (ii) macroscopic and microscopic characteristics of the fatigue fractures, and (iii) construction of fatigue fracture models. More specifically, the review addresses the technological approaches that were used, mechanisms of fatigue crack initiation, features of the S–N curves and Goodman diagrams, and impact of various factors (such as processing, temperature, and corrosion). In addition, it elucidates the damage mechanisms, evolution, and modeling of VHCF in titanium alloys, thereby improving the understanding of VHCF patterns in titanium alloys and highlighting the current challenges in VHCF research. [ABSTRACT FROM AUTHOR]

Objective: To study the antitumor activity of zeylenone in colorectal cancer and its related regulatory mechanism. Methods: Human colorectal cancer cells (DLD-1 and HCT116) and control cell (HcoEpic) were treated with different concentrations of zeylenone (0, 2.5, 5, 10 and 20 µmol/L) for 48 h. Cell viability of DLD-1, HCT116 and HcoEpic were determined by CCK-8 kit. TUNEL staining was used to evaluate cell apoptosis. Caspase-3 activity and LDH level were measured by ELISA. Relative levels of M1 and M2 polarization markers, p-PI3K/PI3K and p-AKT/AKT were detected by Western blot and qRT-PCR. DLD-1 cells were subcutaneously injected into the armpit of nude mice to establish a mouse xenograft tumor model. Intraperitoneal dose of zeylenone given to nude mice was 30 mg/kg, administered once every two days. After 2 weeks, the effect of zeylenone on growth of colorectal cancer tumors was detected. Results: Zeylenone inhibited cell activity and promoted cell apoptosis in colorectal cancer cells. Additionally, zeylenone stimulated M1-polarization and inhibited M2-polarization of tumor-associated macrophages (P<0.05). PI3K/AKT signaling pathway was inhibited by zeylenone in colorectal cancer cells (P<0.05). PI3K/AKT signaling pathway activator (740 Y-P) attenuated the effect of zeylenone on colorectal cancer cells. In mouse xenograft model, zeylenone inhibited the growth of colorectal cancer tumors (P< 0.05). Conclusion: Zeylenone can inhibit colorectal cancer cell activity, promote colorectal cancer cell apoptosis, and promote M1 polarization of tumor-associated macrophages by regulating PI3K/AKT signaling pathway, ultimately inhibiting the progression of colorectal cancer. [ABSTRACT FROM AUTHOR]

Traffic information and driving preference play critical roles in the route selection of drivers and further impact transport management in practice. Some studies have explored the difference between actual and shortest paths for private cars during route selection. However, the quantification of the difference and deviation as well as the impacts of the date on route selection is still seldom investigated. The study proposed a method to quantify the deviation between actual and shortest paths based on big trajectory data and the digital map. Firstly, the rules of private car travel are determined according to the definition of a trip, and the travel trajectory is divided based on these rules to attain many trips. Then, the trip routes and their attributes are generated by geographical information methods. Baidu Map's path planning collects the shortest routes with the optimal distance and time, and the deviation between actual and recommended paths is compared. Finally, the results of 2860 private car trips of nearly 400 drivers in Chongqing, China, reveal that only about 67% of the actual trips match well with the shortest path, which was significantly higher compared to existing studies. However, the deviation between the actual and shortest paths is limited to 9 minutes or 2 kilometers. There was no significant difference between the weekday and weekend in the proportion. Compared with the weekday, the indicators of the weekend are more deviated. Path selection and the deviation vary in travel modes, OD types, drivers' preferences, travel time intervals, and distance intervals., Author(s): Shiguang Wang (corresponding author) [1]; Heng Ding [1]; Zeyang Cheng [1] 1. Introduction In 1952, Wardrop proposed the first principle of traffic equilibrium (user equilibrium, UE), which laid the [...]

Understanding the effect of relevant variables on secondary crashes could provide reliable traffic intervention evidence for decision makers, which ultimately would contribute to the prevention of secondary crashes. Road crashes present obvious spatiotemporal heterogeneity, and previous studies (e.g., geographically weighted regression [GWR] based method) only analyzed the spatial heterogeneity without considering the timescale of related variables. This study proposes a geographically and temporally weighted regression model (GTWR), which adds a time variation to the conventional GWR model. The GTWR model is used to explore the spatiotemporal effects of relevant variables on the secondary crashes on expressways. The empirical study using expressways in Anhui, China, illustrates that the density of rainy days, snow and ice, and occupied middle lanes are negatively associated with secondary crashes. Then the temporal variation characteristics of each influencing factor at different timescales (e.g., weekdays, weekends, and time of day such as night, morning, afternoon, and evening) are analyzed, which reveals the spatial distribution characteristics of the influencing factors in each time period. The finding indicates that the explanatory variables have heterogeneous effects on the frequency of secondary crashes. The model comparison further demonstrates that the proposed GTWR model outperforms the ordinary least squares (OLS) and GWR methods in data fitting and spatiotemporal modeling. The research findings can aid in prevention of secondary crashes on freeways. [ABSTRACT FROM AUTHOR]