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The rapid advancement of high-tech technologies such as aerospace， electronic information， and biomedicine has required more demands on the properties of advanced ceramic materials. Single-characteristic structural or functional materials cannot meet the current requirements， so the high-performance composite ceramics with integrated structure and function have become global research objectives. Directionally solidified oxide eutectic composite ceramics are a class of structural and functional integrated composite materials developed in recent years for long-term service in ultra-high temperature oxidizing environments. They have characteristics such as high melting point， low density， excellent high-temperature strength， and high-temperature creep performance， while also possessing functional properties such as optics， electromagnetism， and biology. The latest development of directionally solidified structure-function integrated eutectic ceramics was reviewed， specifically focusing on Al2O3-based eutectic ceramic systems. The various preparation methods， technical principles， and growth characteristics associated with directionally solidified eutectic ceramics were summarized. Furthermore， the solidification microstructure and structural characteristics observed in a series of Al2O3-based eutectic ceramics were elaborated. The mechanical， optical， magnetic， and biological properties of composite ceramics and their influencing factors were analyzed， and their characteristics， advantages， and application scope were introduced. Finally， the review summarizes the challenges and key bottlenecks faced by directionally solidified eutectic composite ceramics in engineering applications and proposes the main directions for the development of eutectic composite ceramic materials in terms of forming technology innovation， comprehensive performance improvement， and the development of new systems.

In this study, the changes in the amylose content, crystalline structure, Fourier transform infrared (FTIR) properties, pasting properties, and rheological properties of potato starch were explored after radio frequency (RF) treatment at different polar plate spacings (90, 100, 110, 120, and 130 mm). The appropriate RF parameters for 3D printing of potato starch gels were determined. The results revealed that under low plate spacing, the content of amylose decreased and the crystalline form of starch transformed from B-type to C-type. We found that the starch gel with RF treatment at a plate spacing of 90 mm had the best morphology in terms of transparent line uniformity and high retention rate. To sum up, we can conclude that RF treatment at low polar plate spacings is an effective method for preparing 3D printed starch gels.

Oxide eutectic ceramics have excellent high specific strength, high temperature resistance, corrosion resistance, oxidation and creep resistance, and so on, which are considered to be the promising materials to be used in ultra-high temperature oxidation, corrosion and other extreme environments. It shows great application prospects in the new generation of high thrust-to-weight ratio aero-engine for high-temperature hot-end structural components. Laser additive manufacturing technology has become one of the most promising cutting-edge technologies for the preparation of high-performance complex structural components in recent years. Crack defect is easy to occur in the process of laser rapid solidification of ceramics, which seriously affects the quality and performance of the oxide eutectic ceramics components. So, it has become a key factor restricting the engineering application. Two typical laser additive manufacturing technologies for ceramics including laser engineered net shaping and laser power bed fusion were briefly summarized. The crack morphology characteristics of different shaped components formed by the above two technologies were analyzed and compared. The formation mechanism of cracks in laser additive manufacturing of oxide ceramics was explored from the perspectives of microstructure characteristics, stress state. Further, a systematic summary was presented focusing on the improvement of microstructures and the reduction of thermal stress to inhibit crack formation through optimization of process parameters, compositional design, and outfield assistance. Finally, it is pointed out that the future development trends and breakthrough directions of oxide eutectic ceramics by laser additive manufacturing in terms of powder properties, forming primary and secondary factors, and forming technology research.

In this study, we investigated the effect of toughening treatment (55 ℃ for 0, 12, 24, 36, 48 and 60 h) on the microstructure, pasting properties, thermal properties, rheological properties and 3D printability of potato starch. The results showed that the toughening treatment roughened the surface of starch granules and increased the viscosity and pasting temperature of the starch. The toughened potato starch gel showed greater mechanical strength and a more stable and ordered internal structure than the native starch gel. It was found that toughening treatment for 36 h had a significant effect on the printing characteristics of potato starch gels, resulting in the highest printing accuracy and height as well as the best printing performance.

Structured matrices play an important role in scientific computing and engineering applications, such as Cauchy, Toeplitz, Vandermonde, and Hankel matrices. Although these matrices are dense, they can be expressed with only O(n) parameters (generators), where n is the dimension of the matrix. The core idea of the algorithm in this paper is to use matrix generators to explicitly construct local matrix blocks of each process, thereby reducing communication overhead. Additionally, by leveraging the numerical low-rank property of these matrix blocks. This paper further minimize computational overhead. Consequently, the proposed parallel structured matrix multiplication algorithm framework can simultaneously reduce both computational and communication costs, making it suitable for matrix multiplication algorithms like Cannon, Fox, and PUMMA. Extensive numerical tests were conducted on the Tianhe-2 supercomputer, and the results demonstrate that the proposed algorithm achieves an 8.96x speedup compared to the PDGEMM function in ScaLAPACK. [ABSTRACT FROM AUTHOR]

Deep learning is gaining attention in the field of mechanical equipment fault diagnosis. With the help of deep learning techniques, deep neural networks (DNNs) have great potential for machinery fault diagnosis. Deep learning is a subset of machine learning that uses artificial neural networks with multiple layers to deliver state-of-the-art accuracy in various classifications of mechanical rotating parts. Convolutional neural networks (CNNs) are able to automatically learn multiple levels of representations from raw input datawithout introducing hand-coded rules or domain knowledge. Because of this powerful representation learning ability, deep learning has achieved great success in many fields. Although deep learning has achieved promising results in the field of machinery fault diagnosis, existing neural networks suffer from many limitations. The heavy and complex calculation amount puts forward strict requirements for computer hardware, which severely limits its application in actual engineering. To address this issue, this paper proposed a novel lightweight neural network model, ShuffleNet, for high-speed train wheelset bearing fault diagnosis. Based on the thought of module design, this model comprised several ShuffleNet units. Group convolution (GC) and deep separable convolution were used to improve the operation efficiency of traditional convolution in the ShuffleNet unit. Meanwhile, channel shuffle (CS) technology was adopted to overcome the grouping constraint caused by GC and improved the loss accuracy ofthenetwork model. CS operation makes it possible to build more powerful structures with multiple GC layers. Experimental results show that the proposed network model canbe applied in wheelset bearing fault diagnosis underacomplex working condition. Compared to the traditional CNN, ResNets, and Xception, the proposed method can greatly reducethecomputation cost while maintaining diagnosis accuracy. It is clear that the proposed lightweight neural network model, ShuffleNet, is superior to the above comparison models. This provides a new way forengineering applications of DNN technology and overcoming the limitations of computer hardware.

To investigate the aggregation state changes that occur when nanoparticles enter the environment and interact with inorganic minerals, a laboratory experiment was conducted with two types of layered double hydroxides, namely MgAl-LDH20 and MgAl-LDH90, were prepared at respectively 20 °C and 90 °C, meantime the aggregation kinetics of both single and mixed nanoparticle of fullerene-C60 were studied using Zeta potential (ζ) analysis techniques. Consequently, the experiment showed that the critical aggregation concentration (CCC) values of MgAl-LDH20 and MgAl-LDH90 were 209.12 mmol/L and 166.27 mmol/L, respectively; the Zeta potential (ζ) of MgAl-LDHs suspension was significantly decreased after being mixed with C60 suspension at different ratios (120: 1, 60: 1, 30: 1), and the decline degree of ζ increased with the raising of C60 concentration; and the kfast of MgAl-LDH was <3 in the single system, while the kfast of the mixed system was >3 after being added with C60, which suggested that the aggregation of the particles was accelerated due to the electrostatic interactions between MgAl-LDHs and C60, and the presence of MgAl-LDHs could slow down the mobility of C60 in the aqueous environment. Moreover, the stability of the mixed suspension system was determined by MgAl-LDHs when only a few amounts of C60 entered the LDHs suspension system. [ABSTRACT FROM AUTHOR]

The quality stability of tobacco flavor was comprehensively evaluated using a P&T-GC/ MS fingerprinting method, which involved the integration of the angle-cosine similarity, peak matching, and multivariate T2 control charts. The findings suggested the following: The optimal pretreatment conditions for purge trapping involve a purge time of 14 minutes, a purge temperature of 40 °C, and a desorption temperature of 200 °C. Under this condition, the RSD of the characteristic peaks of the volatile components ranged from 1. 36% to 6. 98%, which indicated that the precision of the method was good. Fingerprint mapping combined with angle-cosine similarity and peak matching analysis could quickly identify tobacco flavor samples with changes in chemical components and effectively monitor the quality stability of tobacco flavor; combined with peak matching and multivariate T2 quality control charts, problems such as mismixing of samples and changes in substance content could be detected in time and the quality stability of tobacco flavor could be effectively monitored. This could help to further analyze the causes of changes in chemical components. [ABSTRACT FROM AUTHOR]

【Objective】 Planting date is an important factor impacting plant growth and ultimate yield. The purpose of this paper is to investigate how sowing date affects growth traits and ultimate yield of different rice varieties cultivated in dryland, aimed to provide guidance for farmers to select optimal agronomic management practices. 【Method】 The experiment was conducted in a field and examined three rice varieties: early-mature japonica, middle-mature japonica and late-mature japonica. For each variety, we compared the impact of five planting dates - 25 and 30 April, 5, 10 and 15 May - on its growth and yield traits. 【Result】 In terms of average yield, the three varieties were ranked in the order of early-mature japonica > late-mature japonica > medium-mature japonica. Delaying the planting date of the early-mature variety to 15 May significantly increased its SPAD at filling stage, while planting the late-mature variety on 30 April increased its SPAD at elongation stage compared to other sowing date. In general, delaying the planting date of the early-mature variety or early planting the late-mature variety can increase the areas of their top three leaves. As the sowing date delayed, dry matter accumulation in all three varieties first decreased followed by an increase. Similar trend was also found for the change of plant height of the early-mature japonica. A right sowing date can benefit the grain filling. The sowing date did not have a noticeable effect on seed-setting rate and 1 000-grain weight but could significantly impact both spike numbers and grain number, with the coefficient of variation of the former reaching 20.9% and that of the latter being as high as 23.7%. 【Conclusion】 Our experimental results showed that under dry cultivation, planting the early-mature japonica between May 10 and May 15, and the late- and the medium-mature japonicas between April 30 and May 5 in central region of Jilin province could increase rice yield when other agronomic managements were the same.

The experiment was to study the effects of dietary isochlorogenic acid (ICGA) on early growth performance, intestinal structure, immune performance, and microbial diversity of broilers. 400 one-day-old Kebao broilers, half in male and half female, were randomly divided into five groups with eight replicates in each group and 10 chickens in each replicate. Each group was fed with basal diet (control group), basal diet + 500 mg/kg ICGA (T1 group), basal diet + 1 000 mg/kg ICGA (T2 group), basal diet + 2 000 mg/kg ICGA (T3 group), and basal diet + 3 000 mg/kg ICGA (T4 group). The trial period was 21 days. The results showed that the average daily feed intake (ADFI), average daily gain (ADG), and feed-to-weight ratio (F/G) were not significantly different among the groups (P>0.05). The apparent metabolic rate of crude protein (CP) in T3 group and T4 group was significantly higher than that in control group and T2 group (P<0.05), and the apparent metabolic rate of calcium (Ca) in all experimental groups was extremely higher than that in the control group (P<0.01). The ileal pH value of T3 group was significantly lower than that of other groups (P<0.05). Serum complement C3 content of broilers in each experimental group was significantly higher than that in the control group (P<0.05), and serum immunoglobulin G (IgG) and immunoglobulin M (IgM) content of broilers in T3 group were significantly higher than that in other groups (P<0.05). The villus height of T3 group was significantly higher than that of the control group and T1 group (P<0.05), and the villus-saphenous ratio of T3 group was significantly higher than that of the control group, T1 group, and T2 group (P<0.05). Subdoligranulum&lowbar;variabile in T2 group and T3 group was significantly higher than that in control group and T1 group (P<0.05). Subdoligranulum&lowbar;variabile in T2 group was extremely higher than that in the control group (P<0.01). The study indicates that the nutrient apparent metabolic rate, immune performance, intestinal structure, and intestinal flora were improved by adding ICGA in the diet. The appropriate level of ICGA in the diet of broilers is 2 000 mg/kg. [ABSTRACT FROM AUTHOR]

In order to study the electron-ion dual response properties of n-type organic hybrid ion conductors and the effect of molecular weight on carrier mobility, high molecular weight poly(benzimidazobenzophenanthroline) with a planar rigid trapezoidal molecular chain structure was used to prepare high performance organic electrochemical transistors. The transistors were characterized by UV-visible absorption spectra and transistor device electrical properties. The results show that the n-type organic electrochemical transistors prepared by high molecular weight poly(benzimidazobenzophenanthroline) exhibit extremely high responsiveness (0.034 s), high carrier mobility (4.72 x 10-3 cm²/(V⋅s))and excellent stability(stable running over 120 pulse cycles) in aqueous electrolytes. [ABSTRACT FROM AUTHOR]

[Objective] This study explored the effects of different zinc fertilizer application methods on photosynthetic characteristics, quality and economic benefits of apple to provide reference for rational application of zinc fertilizer in apple. [Method] In Pucheng and Qianxian, Shaanxi, "Changfu No.2" apple was elected for three treatments of no zinc application (control, T1), leaf spraying zinc fertilizer (T2) and integrated water and fertilizer topdressing zinc fertilizer (T3). Soil available zinc content, apple fruit and leaf zinc contents, leaf biological characters, yield, quality and economic benefit were determined under different treatments. [Result] In Qianxian and Pucheng, contents of available zinc in T2 and T3 treatments were higher than that in T1 treatment in soil layers of 0 - 20 and 20 - 40 cm. T3 treatment had the highest values of 1.88 and 1.22 mg/kg in soil layer of 0 - 20 cm and 1.16 and 0.70 mg/kg in soil layer of 20 - 40 cm. In Qianxian, zinc contents of leaves and fruits under T2 treatment were the highest, followed by T3 treatment. In Pucheng, zinc contents in leaves and fruits of T2 and T3 treatments were higher than that of T1 treatment, with the highest values in T3 treatment. In Qianxian and Pucheng, louver thickness, louver weight and chlorophyll content in T2 and T3 treatments were significantly increased compared with T1 treatment. In Qianxian, the fruit shape index of apples was 0.83 - 0.89, with significantly higher values in T1 treatment. In Pucheng, the fruit shape index of apples ranged from 0.81 to 0.91, and T3 had higher values than T1 and T2 treatments. In Pucheng, there was no significant differences in soluble solids and titratable acid contents among treatments. In Qianxian county, the titratable acid content of T2 and T3 treatment was significantly higher than that of T1 treatment, and there was no significant differences in soluble solids among treatments. In Qianxian and Pucheng, contents of soluble sugar and Vc in T2 and T3 treatments were significantly higher than those in T1 treatment. In Qianxian, the highest apple yield and net profit were 30 961 kg/hm² and 82 505 yuan/hm² in T2 treatment, which were increased by 45.49% and 2.85% compared with T1 treatment. The yield and net profit of T3 in Pucheng were the highest, which were 29 159 kg/hm² and 78 595 yuan/hm² and were increased by 28.56% and 65.77% compared with T1 treatment, respectively. [Conclusion] Application of zinc fertilizer improved contents of zinc in soil, apple eaves and fruit, as well as the yield and quality of apple. From the perspective of yield and economic benefits, he effect of water and fertilizer combined application of zinc fertilizer was more stable than that of foliar spraying. [ABSTRACT FROM AUTHOR]

At present, the working temperature of industrial dust removal filter bag is not higher than 280 °C. The high temperature flue gas needs to be cooled before filtration. In order to prepare a new type of filter material with high efficiency and good temperature resistance, porous geopolymer was prepared by polymerization reaction with fly ash as the main raw material and H2O2 as foaming agent. The morphology, pore structure, flexural strength and filtration performance were characterized. The results show that the optimum addition of H2O2 is 0.98%(mass fraction). The average pore diameters of the lower surface and the interior of the porous geopolymer are 17.3 and 171.5 µm respectively, the porosity is 56. 2%, the flexural strength at room temperature is 2.2 MPa, the filtration resistance is 6. 2 x 10-3 MPa, and the filtration efficiency of PM10 and PM2.5 are 98. 2% and 93. 3%, respectively. After heat treatment at 800 °C, the flexural strength increases to 3.4 MPa, and the filtration efficiency of PM10 and PM2.5 remains above 90%. The filtration resistance increases by 1 x10-3 MPa. Therefore, the fly ash-based porous geopolymer has a good application prospect as a hightemperature flue gas filtration material. [ABSTRACT FROM AUTHOR]

During the urbanization process of China, the planned "New Town" in some cities may be built on the contaminated left-over sites located in former suburban industrial zones. The complexity of the land-use plans of urban new towns may cause uncertainties to the investigation and evaluation of contaminated sites. The present study chooses a contaminated left-over site from fuel oil leakage accidents, which is now planned as cultural event facility in an urban new town. Based on sample analysis results of the site, human health risk assessment is conducted on the soil-sampling points with total petroleum hydrocarbons (C10 - C40) with excessive levels considering the actual scenes of cultural event facility land-use. The results show that total petroleum hydrocarbons in the studied site have significant human health risks. However, the human health risks from contaminants are underestimated upon the relevant land-use classification in current national standards. The present study reveals the existing "grey zone" in risk assessment and screening values of contaminated sites, coupling with the potential negative impacts on users' health risks, which should arise sufficient concerns in the practice of contaminated site investigations and remediation in China. [ABSTRACT FROM AUTHOR]

In order to solve the problems of the non-slip belt conveyor in the tobacco primary processing line of cigarette factory, such as the breeding of tobacco insects, the low efficiency of personnel cleaning, an automatic cleaning device for the non-slip belt conveyor was designed. The device was installed under the non-slip conveyor belt. In the automatic cleaning mode, its lifting mechanism controlled the brush lifting. High frequency and high pressure atomized water was used to clean the surface of the conveyor belt. The surface of the belt was blown dry with high pressure air. The application results showed that using this device to clean the non-slip belt conveyor could effectively control the tobacco insects, improve the internal quality of the product, reduce the number of cleaning personnel and safety hazards of the silk production line equipment, and improve the operation efficiency of the equipment. [ABSTRACT FROM AUTHOR]

Currently, general-purpose processors generally support 64-bit floating point operations. In large-scale and long-time scientific numerical calculation, the cumulative effect of rounding errors in floating-point operations may lead to unreliable numerical results. Therefore, to effectively control errors, designing high-precision, efficient and reliable floating-point numerical algorithms is very important. By using error-free transform and double-double format, this paper realizes a high-precision mathematics library based on SCILAB software platform. The evaluation of the polynomials in power basis, Bernstein form and Chebyshev basis is carried out on the Intel platform and the domestic FT processor platform. The results prove the validity of our proposed high-precision mathematics library. This library has independent intellectual property right and can run on the self-dependent and manageable domestic processor, which will support the national high technology research. [ABSTRACT FROM AUTHOR]

Aiming at the insulator sheds' dropping off, study on image threshold segmentation, edge detection, insulator recognition and fault diagnosis were carried out, characteristics of insulator and the background area were summarized, a new method to recognize and diagnose fault insulator was proposed. The OTSU was applied for image segmentation, and wavelet modulus maximum method for edge detection, Hough transform was improved to detect ellipsis quickly, ellipse parameters were used to design the classification standards and accurately recognize the insulator. Finally, fault diagnosis was realized based on location information. The method was verified using aerial images. The results indicate that ellipse parameters can be calculated, functions such as edge detection, insulator recognition, and fault diagnosis can be realized, and the algorithm responds quickly and accurately. [ABSTRACT FROM AUTHOR]

According to a slow development problem of the mine seismic exploration technology, based on the channel wave seismic exploration technology, a design conception of the third generation node type seismograph was applied to develop a new type channel wave seismograph with "a node type design, independent excitation, distributed acquisition, three channel storage and centralized recovery". A flexible, unconstrained and free layout of the underground mine channel wave seismic observation system could be realized. The completed acquisition system with no host computer, no cable, no communication, synchronous acquisition and other advantages and with a high and rapid construction could meet the requirements of the channel wave seismic exploration under the overlong and over wide mining face, no connection between the gateways as well as the mining block, mining panel and crossed layers condition. [ABSTRACT FROM AUTHOR]

We propose an efficient bit-loading algorithm to minimize the total power to transmit a target rate of a single user in OFDM communication systems. Considering the digital modulations exploited by 802. 11a, which are BPSK, QPSK, 16QAM and 64QAM (constellation using Gray code and each sub-carrier carrying a maximum of 6 bits) , ⌊ RT/6 ⌋ subcarriers which have litter power addition are allocated with 2 bits each time. The proposed bit loading algorithm is optimal and has the same performance as Hughes-Hartogs algorithm, but greatly reduces the computational complexity. Simulation results show that the proposed bit loading algorithm has the same bit allocation results as Hughes-Hartogs algorithm, but the computational complexity is less than 50% compared with that of Hughes-Hartogs algorithm. The computational complexity will be further reduced when the transmission rate or subcarriers number increases. [ABSTRACT FROM AUTHOR]

With the acceleration of agricultural modernization, problems such as agricultural nonpoint source pollution and the proliferation of agricultural carbon emissions have become increasingly prominent. In this context, promoting sustainable agricultural development; ensuring national food, resource, and ecological security, and accelerating high-quality agricultural development have become inevitable trends. Promoting the green development of agriculture is one of the core tasks of high-quality agricultural development, and the implementation of green production behavior is the key to promoting the green transformation of agriculture. Farmers are not only the main bodies of agricultural production, but also the main implementers of green production. Therefore, it is of great practical significance to clarify the factors influencing farmers' green production behavior and the relative importance of each influencing factor. Based on the perspective of the entire industry chain and survey data of 360 lychee growers in major lychee-producing areas of Guangzhou City from May to August 2022, this study uses an ordered logistic regression model to explore and analyze the influencing factors of the green production behavior of lychee growers. The importance of these results is then ranked using the random forest model. The organic combination of these two methods overcomes the limitations of a single statistical method. The results show that 1) the age and part-time employment of lychee growers and the lychee planting area significantly negatively affect the implementation of their green production behavior; 2) production safety, environmental, and policy cognition can effectively promote the adoption of lychee growers' green production behaviors; 3) village rules and regulations, increasing green production subsidies, identifying geographical indication product brands, government satisfaction, participating in training and increasing agricultural income all significantly positively affect the lychee growers' green production behavior; and 4) the relative importance of explanatory variables ranks from high to low as follows: policy cognition, formulating village rules and regulations, production safety cognition, identifying geographical indication product brands, environmental cognition, increasing agricultural income, age, the planting area of lychee, participating in training, increasing green production subsidies, government satisfaction, and part-time employment. The four influencing factors are also ranked in order of importance: cognitive characteristics, external environment, family business characteristics, and personal characteristics. Accordingly, this study suggests that the government should first, based on respecting the subjectivity of lychee growers, formulate relevant policies according to local conditions to stimulate the internal power of their sustainable development, stimulate their consciousness, and improve their responsibility toward green production by increasing green production subsidies by realizing the visualization of income and benefits, building a diversified publicity and training system, and other means. A supervision mechanism should be established to standardize the behavior of lychee growers, and measures such as market supervision, village rules, and regulations should be adopted to constrain them. Finally, governments must create an external environment conducive to green development by appropriately expanding the planting scale to reduce the proportion of part-time lychee growers; building a high-quality brand image; promoting cooperation among research institutes, universities, and lychee growers; and comprehensively improving their green production levels.

ObjectiveTo evaluate potential health risk and the dietary exposure of aluminium in residents of Hangzhou.MethodsThe dietary exposure of aluminium in residents of Hangzhou was calculated by simple distribution assessment method based on the data of aluminium-containing additives from 2015 to 2021 in Hangzhou and the data of food consumption survey in 2015.ResultsThe average weekly and the 95 percentile （P95） exposure were 0.416 and 1.986 mg/kg·BW， which were lower than the tolerable weekly intake （PTWI， 2 mg/kg·BW） by Joint FAO/WHO Expert Committee on Food Additives （JECFA）. Steamed stuffed buns， noodles， Chinese pastry， fried bread stick and steamed buns were the main sources of exposure， accounting for 85.9% of the total exposure. If the national food safety standard on ammonium-containing additives was strictly implemented， the exposure will reduce by 88.2% and 84.0%， respectively.ConclusionThe risk of dietary aluminium in residents of Hangzhou was low and acceptable. However， the exposure of high-consumption groups （P95） was close to PTWI， and the P95 exposure of people under 18 had exceeded PTWI which deserves attention. Measures should be taken to reduce the health risks caused by excessive aluminium exposure.

In high-performance computing,the accumulation of rounding error in the process of solving the large-scale,long time and ill-conditioned problem will lead to invalidated results.These results are useful for the developers to debug programs and check their correctness.Therefore,the reproducibility of the numerical results of the algorithm becomes very important.Based on the OpenBLAS’s framework,combining with Demmel’s reproducible method in ReproBLAS and multilayer block technology proposed by Castaldo,this paper designs a reproducible algorithm of multithreaded DGEMV for Phytium processor with rounding error analysis and error free transformation.Numerical experiments show that the output of the algorithm is the same as that of the ReproBLAS,which verifies the reproducibility.Our algorithm is up to 2x faster than that in ReproBLAS.Compared with the DGEMV function of OzBLAS proposed by Mukunoki,our algorithm runs at least 20x faster than that in OzBLAS with single thread,and 9x faster than that in OzBLAS with multi-threads.Theoretical analysis and numerical experiments illustrate that improved algorithm is accurate,validated and efficiency.

Objective To investigate the effect of Raddeanin A （RDA） on the proliferation and apoptosis of cervical cancer HeLa cells and to explore the possible mechanism. Methods HeLa cells were cultured in vitro and treated with RDA at a concentration of 0, 5, 10, 20, and 40 μmol/L for 48 h. Cell proliferation rate was determined by CCK-8. The half-maximal inhibitory concentration （IC50） was calculated to determine the drug concentration. Flow cytometry was used to detect cell apoptosis, and western blot was employed to detect the expression levels of Bcl-2, Bax, Cleaved-caspase-3, p-PI3K, p-Akt, and p-mTOR proteins. Hela cells were divided into four groups： control group, IGF-1 group, RDA group and combined treatment group. The proliferation rate, apoptosis rate, relative expression levels of p-PI3K, p-Akt and p-mTOR proteins were detected and compared among different groups. Results The proliferation rate of HeLa cells was significantly declined, whereas the apoptosis rate was significantly elevated with the increasing concentration of RDA （both P < 0.05）, the relative expression levels of Bax and Cleaved-caspase-3 proteins were significantly up-regulated （both P < 0.05）, whereas those of Bcl-2, p-PI3K, p-Akt and p-mTOR proteins were significantly down-regulated （all P < 0.05）. After the activation of PI3K/Akt/mTOR signaling pathway by IGF-1, RDA could still inhibit the proliferation of HeLa cells and down-regulate the relative expression levels of p-PI3K, p-Akt and p-mTOR proteins （all P < 0.05）. Conclusion RDA can inhibit the proliferation and promote the apoptosis of cervical cancer HeLa cells by suppressing the PI3K/Akt/mTOR signaling pathway.

In recent years,AI technology has been widely adopted in many application domains,amongst which,intelligent medical applications such as clinical decision support systems have attracted much attention.However,since the current wave of AI applications are based on predictive models crystalized from historical data,the feature and quality of data will affect AI applications' performance directly.Medical data are inherently imbalanced as rare disease cases are always the scarce in existing case archives,while considered more important.The "data imbalance problem" is still considered a difficult research problem in machine lear-ning.This paper conducts a literature review on the research efforts targeting at techniques to handle "imbalanced data" in gene-ral as well as the ones in intelligent medical area.We then use research publications from the SIGKDD conference dedicated to knowledge discovery and data mining as a sample pool,to find people's preferred approach to address "imbalanced data" problem in a given domain.Finally,based on approaches,we identify from the survey,and conduct experiments on two typical medical predictive model learning scenarios,to validate the know-how we acquired in this study.

In recent years,relying on the research breakthrough and rapid development of blockchain technology,a variety of di-gital currencies are rising and flooding into the market.As the currency with the strongest privacy in the UTXO model of blockchain so far,the anonymity technology of Zcash not only provides a strong guarantee for users' privacy,but also has high scienti-fic research value and a wide range of application prospects.Therefore,in order to standardize the legal use of digital currency and explore the wider application prospect of digital currency anonymity technology,scholars from all walks oflife have also conducted research on the anonymity and anti-anonymity technology of Zcash from different angles.Focusing on Zcash,a new digital currency,we first introduce thegeneral framework of Zcash.Secondly,the anonymous technology adopted by Zcash:zk-SNARKs and shielded pool transaction technology,are sorted out.Then we summarize and analyzethe research on Zcash tracking technology by scholars from all walks of life.In the end,anonymous technology and tracking technology development of Zcash are prospected.

The conventional magnetic levitation belt conveyor adopts the electromagnetic structure composed of permanent magnets and electromagnets, which has the problems of easy heat generation and high current loss under the working conditions with high demand of magnetic levitation support force. To solve this problem, an electromagnetic structure based on Halbach array is proposed in this study. The mathematical model of electromagnetic structure optimization is established with the maximum magnetic induction intensity of electromagnetic structure as the objective function and the size of electromagnetic structure and the range of magnetic induction intensity distribution as the constraints. When solving the mathematical model of electromagnetic structure optimization, the Teaching and Learning Optimization (TLBO) algorithm is easily to fall into the local optimum. To solve this problem, an improved TLBO algorithm is proposed so as to enhance the diversity and search ability of the population by introducing new populations through screening and improving the learning methods in the teaching stage and mutual learning stage. The test results show that the accuracy and stability of the improved TLBO algorithm are better than the standard TLBO algorithm. The improved TLBO algorithm is used to solve the electromagnetic structure optimization mathematical model of the magnetic levitation belt conveyor. The optimal electromagnetic structure parameters are obtained as follows: the height of a single permanent magnet in Halbach array is 7 mm, the width is 9 mm, and the number of permanent magnets is 7. The experimental results show that under the same size conditions, the maximum magnetic induction intensity of the Halbach array-based electromagnetic structure is increased by 47.69% compared with the permanent magnet-based electromagnetic structure.

Grain safety is of fundamental importance for the whole society. The traditional methods cannot fulfil the requirements of whole grain chain traceability. Also it is hard to combine with the modern technological developments. In view of the two bottlenecks, and based on the analysis of the application and research status of block chain technology in grain industry, the characteristics of block chain technology, such as “decentralization”, “timestamp” and “unchangeable”, and the differences between block-chain traceability mode and traditional traceability mode, this article proposed the application scenarios of block chain technology in the construction of grain traceability system, summarized the development trend of block chain technology innovation, and put forward the key issues that should be paid attention to.

In order to deeply analyze the micro-displacement deformation performance of parallel two-axis straight circular flexure hinge，based on the assumption of small deformation of elastic beam，the bending theory of variable cross-section continuous beam and the principle of calculus superposition，the calculating formulas of angular deformation and angular stiffness are derived. According to Hooke's law，the calculating formulas of elongation and tensile stiffness for tension-compression deformation are obtained，and the flexure hinge under different structural parameters is also calculated. Finite element analysis is carried out，and structural parameters affecting angular stiffness and tensile stiffness are studied. The results show that the error between finite element solution and analytical solution of angular stiffness is less than 7%，the error between finite element solution and analytical solution of tensile stiffness is less than 3%; stiffness is proportional to minimum thickness and modulus of elasticity，inversely proportional to cutting radius，and minimum thickness is proportional to rigidity. The effect of minimum thickness is the most significant，cutting radius is the second，and modulus of praseodymium is the weakest.

Wireless charging has the advantages of safe charging and high efficiency. It has been applied to wireless data acquisition systems to solve the problem of power energy life and prolong the working life of the system. However, wireless data acquisition systems based on wireless charging currently use additional wireless communication modules to transmit data collected by sensors, which increases the volume and power consumption of the sensor nodes. It is undoubtedly catastrophic in data acquisition applications such as implantable medical devices and volume-restricted confined containers. Considering the hybrid transmission of energy and data in wireless charging system, the Qi standard is expanded in this paper to realize the transmission of sensor acquisition data by means of wireless charging system. Without additional wireless communication module, this method reduces the volume and power consumption of sensor nodes, simplifies the system circuit and reduces the cost.

The magnetic coupler produces eddy current in the conductor by permanent magnet magnetic field to realize the transmission of torque and rotational speed,while the eddy current loss will lead to permanent magnet temperature rising. When the temperature is higher than the temperature of the permanent magnet demagnetization,it will lead to irreversible permanent magnet demagnetization and magnetic coupling loss of working ability. An outer rotor is designed to be the magnetic coupling of the rotor of the inner rotor. The relation among the output speed,the torque and the coupling length is obtained by using ANSYS for electromagnetic simulation analysis. Based on the theoretical analysis and simulation calculation,the number of magnet and air gap length on the influence of the eddy current loss is also verified,and a including heat dissipation fin and heat dissipation structure of centrifugal fan is devised. By analyzing the Flow Simulation,the heat dissipation effect of the heat dissipation structure on the magnetic coupling can be verified,and the permanent magnet can be stabilized and operated in the long term.

The multi-mass elastic torsional system has the feature of large speed fluctuation and long vibration time.The system state space model is built based on the system analysis,and the parameters of this model are estimated by using Simulink Parameter Estimation Toolbox.The system speed is controlled by using dynamic matrix control（DMC）algorithm.The DMC controller is converted into embedded C code which is executable for PLC by using Simulink Coder toolbox in Matlab.After being compiled by Automation Studio,it will be downloaded to X20 PLC to control the real system.Both the simulation and practical system test shows that the model is accurate and DMC algorithm is better than cascade PID algorithm in dynamic performance.

Organoids are an in vitro model that can simulate the complex structure and function of tissues in vivo . Functions such as classification, screening and trajectory recognition have been realized through organoid image analysis, but there are still problems such as low accuracy in recognition classification and cell tracking. Deep learning algorithm and organoid image fusion analysis are the most advanced organoid image analysis methods. In this paper, the organoid image depth perception technology is investigated and sorted out, the organoid culture mechanism and its application concept in depth perception are introduced, and the key progress of four depth perception algorithms such as organoid image and classification recognition, pattern detection, image segmentation and dynamic tracking are reviewed respectively, and the performance advantages of different depth models are compared and analyzed. In addition, this paper also summarizes the depth perception technology of various organ images from the aspects of depth perception feature learning, model generalization and multiple evaluation parameters, and prospects the development trend of organoids based on deep learning methods in the future, so as to promote the application of depth perception technology in organoid images. It provides an important reference for the academic research and practical application in this field.