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Ensuring food security requires not only increasing production but also reducing food loss and waste (FLW). In recent years, China's total grain production has continuously reached a new high, but the problem of FLW is still prominent. The control of FLW reduction also still needs in-depth development. The development of digital technology plays an important role in FLW reduction. This paper has briefly reviewed the current situation of FLW reduction and the application of digital technology in food supply chain, and analyzed the pathway of digital technology in FLW reduction from four fields of food production, food circulation, food sales and consumption. It also proposes corresponding countermeasures and suggestions for China's work on FLW reduction. In order to further leverage the role of digital technologies in FLW reduction of all links of the food supply chain, efforts should be made to improve the monitoring and assessment of FLW and establish a regular FLW investigation system. Policy guidance should be strengthened to establish and improve the long-term management mechanism of FLW. The digital literacy and skills of all subjects in the food supply chain should be cuitivated to promote the soft power of FLW with the digital technology management. Leverage digital technologies to promote grain conservation and loss reduction by addressing each link in the grain supply chain.

Objective: In order to improve the yield of oryzanol of rice bran. Methods: Rice bran was selected as the research subject, and Saccharomyces cerevisiae and Bacillus subtilis were selected as solid-state fermentation strains through single-factor experiments. The mixed bacterial solid-state fermentation process was optimized by Box-Behnken response surface method combined with the single factor experiments, based on the content of oryzanol. The antioxidant activity of the fermentation extracts was evaluated using DPPH and ABTS free radical scavenging assays. Scanning electron microscopy （SEM） was used to analyze the principle of oryzanol enrichment in mixed bacterial solid-state fermentation. Results: Under the of mixed bacterial treatment of saccharomyces cerevisiae and Bacillus subtilis, the optimal fermentation conditions for rice bran oryzanol was determined to be a fermentation time of 44 h, a fermentation temperature of 34 ℃, an inoculum size of 10%, and a moisture content of 40%. Under these conditions, the oryzanol content was （7.816±0.038） mg/g, which was 1.9 times higher than that of unfermented rice bran. The extracts prepared by mixed bacterial solid-state fermentation exhibited strong DPPH and ABTS free radical scavenging activity, with IC50 values of （0.220±0.007）, （0.409±0.014） mg/mL, respectively. These values represented a reduction of 28.6% and 39.7% compared to unfermented rice bran. SEM observation revealed showed that that the surface of rice bran tissue had less oil, a looser and more porous structure after mixed bacterial solid-state fermentation, which was more conducive to the release of rice bran oryzanol. Conclusion: Mixed solid-state fermentation of bacteria significantly increases the oryzanol content and antioxidant activity of rice bran.

Objective To explore the efficacy of wrapping the hepatic artery with detached ligamentum teres hepatis during pancreaticoduodenectomy (PD) on preventing postoperative intra-abdominal hemorrhage. Methods A total of 186 patients who received PD in the First Affiliated Hospital of Xinjiang Medical University from June 2020 to June 2022 were divided into wrapping group (n=86) and non-wrapping group (n=100) according to whether the detached ligamentum teres hepatis was used to wrap the hepatic artery during the operation. The clinical data on perioperative and postoperative complications were collected and retrospectively analyzed in two groups. Results PD was successfully performed and completed in both groups, and there was no significant difference in age, gender, BMI, length of hospital stay, operative time and intra-operative blood loss between two groups (P＞0.05) . The incidences of pancreatic fistula, biliary fistula and abdominal infection were similar in two groups (P＞0.05) , but the incidence of postoperative bleeding in wrapping group was significantly lower than that in non-wrapping group (1.16% vs 9.00%, P＜0.05) . Logistic regression analysis showed that the pancreatic and biliary fistulas of grade B/C were the independent risk factors for postoperative abdominal bleeding after PD (P＜0.05) , and the wrapping of the hepatic artery with the detached hepatic round ligament during operation was an independent protective factor for postoperative abdominal bleeding after PD (P＜0.05) . Conclusion Wrapping the hepatic artery with detached ligamentum teres hepatis during PD surgery may reduce the incidence of postoperative abdominal bleeding and is simple, safe and feasible to perform without additional complications．

Modified asphalt with waste tire rubber powder was prepared by using orthogonal experimental design of four levels and four factors. Aging test of film oven was carried out with the optimized combination of rubber powder modified asphalt.The performance changes of different asphalts were evaluated from macroscopic point of view, and chemical components and revolution of rubber modified asphalt were analyzed from microscopic point of view by three major indicators of asphalt, infrared spectroscopy, four component analysis and differential thermal test. The results showed that the optimal ratio of modified asphalt was 17% （mass fraction, the same below） of rubber powder amount ,180 ℃of mixing temperature, 1/6 of modifier mass ratio and 4% of plasticizer amount. The shape and position of the characteristic infrared absorption peak of asphalt modified with rubber powder remained unchanged, but intensity changed. Meanwhile, the content of chemical components was changed. The components of saturated and aromatic decreased, but resin and asphaltene components increased. The addition of rubber powder reduced degradation rate of the asphalt, increased initial degradation temperature and final residue content, and improved thermal stability of the asphalt.

As the cavitation is a long - term disturbing problem in hydropower industry, carrying out anti - cavitation research for hydropower machinery is of great significance for promoting hydropower development and scientific carbon reduction. In this work, the cavitation mechanism and prevention strategy for hydropower mechinery were briefly explained. Based on this, the current research status and application of anti - cavitation coating materials were emphatically discussed. Finally, the current problems and the future research direction of new anti - cavitation materials were prospected.

Molybdenum alloy bars with the different ZrO2 mass fraction were prepared by powder metallurgy process. The effects of ZrO2 mass fraction on the microstructure and mechanical properties of the molybdenum alloys were studied by tensile mechanical properties test, hardness test, and optical microscope analysis. The results show that, the grain size of the molybdenum alloys is refined by the addition of ZrO2. With the increase of the ZrO2 mass fraction, the hardness and tensile strength at room temperature of molybdenum zirconia alloys increase gradually. When the mass fraction of ZrO2 is 2.5%, the hardness reaches the highest value as HV10 240, and the tensile strength reaches the maximum value as 820 MPa.

In order to study the relationship between the macro-bending loss characteristics of the single-mode fiber and the temperature change, the thermo-optical effect and thermal expansion effect are corrected according to the theoretical formula proposed by Faustini L. Based on this formula, the macro-bending loss of SMF28 and 1060XP single-mode fiber with core-cladding-infinite coating structure under the influence of temperature is simulated and analyzed. The influence of temperature, wavelength, bending radius and other factors on the macro-bending loss of SMF28 single-mode fiber is explored, and the linear fitting results between the temperature and the two kinds of single-mode fibers are obtained. The results show that the macrobending loss increases with the decrease of bending radius, and the increase of wavelength. The loss also decreases with the increase of temperature. Under certain bending radius and wavelength, the macro-bending loss and temperature are in monotonic relationship, which means increasing the number of bending turns can effectively increase the sensitivity to temperature.

In order to solve the problem of large squeezing deformation control of roadway between two goafs, the panel track-roadway between two goafs in Fenghui coal mine is taken as the engineering background, and the methods of on-site monitoring, theoretical calculation and numerical simulation are comprehensively used.The deformation characteristics of the roadway, the characteristics of the overlying strata structure, the plastic failure modes and stress environment of the surrounding rock under different mining conditions are studied.The squeezing deformation mechanism of the roadway between two goafs is revealed.A combined support design of anchoring and grouting with "strengthening key parts and grouting modified surrounding rock" as the core is proposed.The on-site monitoring results show that the new support design has good control effect on the squeezing deformation of the roadway between two goafs, which can provide reference for the surrounding rock control under similar conditions.

The USA Weapons of Mass Destruction-Civil Support Teams (WMD-CST) is composed of various members of the US National Guard, and each state has at least 1 team. As state-owned emergency rescue forces, these teams have very high professionalism, immediate response ability, and comprehensive support ability. Their team formation, training, certification, and operation are worthy of reference

[Purpose/Significance]Social commerce research presents the characteristics of interdisciplinary studies, because of which ts research perspectives, research methods and research content are in a more decentralized state. This study aims to review the current social commerce research and presents the, analysis of its development and characteristics. [Method/Process] We first obtained Chinese and English journal papers published from 2010 to 2019 from CNKI, CSSCI, SCIE, SSCI databases. We then discussed the current progress and characteristics of social commerce research from time distribution, theme changes, high citation papers, and high-frequency keywords. [Results/Conclusions] We believe that there are still some topics that can be excavated in the study of social commerce: Firstly, we need to further explore such user behavior research topics as user perception and the strategy choices, and business management, technical support and information research in social commerce context. Secondly, the research theory has presented a certain interdisciplinary perspective, and we can find and explain the practical problems in social commerce from the perspective of more subject areas. Thirdly, the applicability of computer science, information science and psychology research methods to the field of social commerce can be discussed and studied.

BACKGROUND This article reviewed the research progress of pretreatment techniques for the analysis of precious metal elements in geological samples in recent years. The fire assay, alkali fusion, acid decomposition and adsorption methods used in the separation and enrichment of samples and absorption, tellurium co-precipitation, ion exchange, solvent extraction, distillation, and biosorption methods commonly used for sample decomposition were reviewed. The characteristics and deficiencies of each method were investigated, and the future development direction of the method is prospected. OBJECTIVES In order to make the analysis results accurate and reliable, it is necessary to select the appropriate means of sample decomposition and separation and enrichment to ensure complete sample decomposition, effectively eliminate the interference of co-existing ions and matrix effect, enhance the precious metal element test signal, and improve the signal-to-noise ratio. METHODS The fire assay method used for sample decomposition has been continuously explored and improved by analysts, and has become the best method to decompose precious metals. However, it still has the disadvantages of large reagent consumption, high cost, and long procedure. Although the alkali fusion method can decompose almost all geological samples, the resulted solution contained a large amount of sodium salt, which needed to be further purified. The acid decomposition method was mainly based on the high-pressure sealed Carius tube digestion, but it was limited by the nature of the sample. Different separation and enrichment methods were highly targeted. For example, the adsorption method was mostly used for the enrichment of Au, Pt, and Pd. The distillation method was only suitable for the analysis of Os and Ru. RESULTS Precious metal elements had features such as strong particle effects, complex and diverse forms, and ultra-trace amounts, so it was necessary to choose a suitable pretreatment method according to the type of samples. CONCLUSIONS Based on the existing precious metal decomposition methods, in combination with the current new experimental equipment and conditions, more efficient and rapid decomposition technologies should be sought and the background of the procedure and pollution problems in each step strictly controlled, realizing multi-technology and multi-method integration and meeting the requirements of precious metal analysis.

In order to explore the regulating effect of the new type of gibbereUin GA4 on the growth and development of Dendrobium offcinale, the treatment groups with different concentrations of GA4 were set up, with GA3 as the positive control and clean water as the blank control. The effects of GA4 on the growth and quality of Dendrobium offcinale were determined, and the contents of the three endogenous hormones, such as the auxin (IAA), gibberic acid (GA3) and zeatin (ZT) were determined by using the high performance liquid chromatography. The results showed that the plant height, plant diameter, biomass, polysaccharide content and total content of Dendrobium offcinale increased with the increase of GA4 concentration. GA4 40 and GA4 80 had the most significant effects on the growth and quality of Dendrobium offcinale during the harvest period. Except for the plant height, the other indexes in the treatment groups of GA4 20 and GA4 40 were significantly higher than those in the positive control with the same concentration of GA3 and blank control. The correlation analysis showed that the plant diameter and biomass were the key growth indicators affecting the quality of Dendrobium offcinale. The exogenous spraying of GA4 could significantly affect the contents of IAA, GA3 and ZT in Dendrobium offcinale. The contents of these three endogenous hormones increased significantly after 100 days of the treatment, and were significantly higher than those in the positive and blank controls. GA4 may break the summer dormancy by regulating the endogenous hormones, causing the secondary growth of plants, thereby promoting the growth and quality of Dendrobium offcinale. The results could provide references for the development and utilization of GA4. [ABSTRACT FROM AUTHOR]

It was studied that the aquatic plant Acorus calamus and reed affected the enrichment ability of compound heavy metals (i. e. V, Cr and Cd) and physiological response and the two plants repair effects of polluted water were investigated by heavy metals. Results show that the tolerance index of two plants decreases with heavy metals concentration increasing in water body, whereas the growth of the Acorus calamus is better than that of reed. Under different concentrations of heavy metals, both Acorus calamus and reed show the strongest enrichment ability of Cd, followed by Cr, while the enrichment ability of V is relatively weak. Under same heavy metal concentration, Acorus calamus on the total enrichment quantities of three kinds of heavy metals are better than those of reed. When the mass concentration of heavy metal is 15 mg·L-1, the enrichment of three heavy metals by Acorus calamus is 1065.02, 1754.80 and 4372.40 mg·kg-1 for V, Cr and Cd, respectively. The enrichment index of Acorus calamus underground part of V, Cr and Cd is 2.1, 1.5 and 1.8 times better than that of reed. It is concluded that Acorus calamus is more suitable for the remediation of heavy metal pollution by V, Cr and Cd.

In slim hole sidetracking drilling,88. 9 mm diameter direct type drill pipe can effectively reduce the pressure loss along the path and increase the rock carrying,also can transfer torque effectively,rotary drilling to improve drilling efficiency. In order to meet the actual needs,improving the carrying capacity of 88. 9 mm drill pipe joint in slim hole drilling,this paper presents a low tooth-double shoulder-special thread. By 3 D Finite Element analysis,the performance of thread connection were studied,including the stress in three-dimension under different loads and the limit torque under different axial tensile loads. And draw out the limit torque curve of the tool joint. Forming a quickly method to determine the tool joint limit torque under different tension. The research is of great significance for guiding the selection and optimization of the drill pipe joint,analyzing the limit load of the drill pipe joints and determining the the limit drill depth.

Twenty-nine species samples of higher plants which belong to twenty families and seven soil samples were collected from a vanadium smelter. The contents of heavy metals in the native plants and soil were analyzed by ICP-MS and ICP-OES. The results show that the soil of the smelting plant area has general Cr,Cd and V pollution phenomena; moreover,V and Cr pollution is conspicuous. V,Cr,Cd and Pb are detected from all these collected polluted higher plants,and the content of V is the highest. Pteris vittata L,the native plant,has the highest V content; the accumulation amounts of the aboveground part and the underground part are 86.51 mg·kg-1 and 814.25 mg·kg-1,respectively. The enrichment and transport capacity of Daucus carota L is obviously higher than that of other plants; the accumulation amounts of the aboveground part and the underground part are 18.56 mg·kg-1 and 5.66 mg·kg-1,respectively. These two kinds of plants show high tolerance to heavy metal pollution in the vanadium smelting plant area,and they can be used as pioneer species of pollution remediation.

In order to study the ability of lees to adsorb heavy metals,this article was focused on the effects of wastewater p H values,Pb2+ and Zn2+ mass concentrations,and adsorption time on the adsorption quantity of Pb2+ and Zn2+ from simulated acid mine drainage using lees. Test results show that the maximum removal rate appears when the p H value is 4. The adsorption of Pb2+ by lees accords with the Langmuir equation,but the adsorption of Zn2+ is followed by the Freundlich equation. Under the optimal conditions,the maximum adsorption capacity of Pb2+ and Zn2+ by lees is 8.29 mg·g-1 and 15.31 mg·g-1,respectively. The adsorption process reaches equilibrium after 4 h,in agreement with the second-order kinetics model. The contents of cellulose,hemicelluloses and lignine in the lees is 23.3%,65.5% and 0.5%,while become 19.6%,42.3% and 2.6% after adsorption of Pb2+ and Zn2+,respectively. The electro-negativity of lees increases while the p H value raises,and it reduces after adsorption of Pb2+ and Zn2+. Fourier transform infrared spectra indicate that the main functional groups are amide and ester reacting in the adsorption process.

Natural clinoptilolite was modified by different concentrations of hydrochloric acid. Systemic investigations were performed on the channel characteristics, chemical composition, surface potential, and cation exchange behavior of the modified clinoptilolite. It is found that the surface of the modified clinoptilolite becomes loose and rough, the contents of K+, Na+, Ca2+, and Mg2+ slightly decrease, the surface negative charges increases, and the cation exchange capacity decreases to some extent. The specif-ic surfaee area and total pore volume are improved and the maximum values of them increase from 35.97 m2·g-1 and 0.0761 m3·g-1 to 64.46 m2·g-1 and 0.1156 m3·g-1, respectively. The distribution of micropores, mesopores, and macropores is obviously impacted, and the type of zeolite cavities is determined to be uneven slits by the hysteresis loop shape, indicating that this aeid modification cannot change zeolite cavities.

This study was conducted in order to investigate the distribution characteristics of mineral elements in different sesame tissues. The content of Ca, Mg, Fe, Cu and Zn in different tissues was determined by inductively coupled plasma optical emission spectrometry (ICP-OES). The results showed a significant variation of mineral elements content in the different sesame tissues. The highest average Ca content was in leaves (2151.61 mg/100g), followed by 20 d seeds (984.18 mg/100g). Mg was predominant in leaves and 20 d seeds with an average content of 390.23 mg/100g and 300.01 mg/100g, respectively. The content of Fe in leaves was the highest, with an average of 19.98mg/100g. The Cu and Zn contents were the lowest in different tissues, both less than 5.00 mg/100g, and the highest Cu content in leaves. In mature seeds, Ca and Mg contents were the highest, with an average of 1133.64 mg/ 100g and 382.85 mg/100g, respectively. Regarding seed coat color, brown sesame seeds exhibited the highest Ca, Mg, and Cu contents with average values of 1342.68 mg/100g, 445.95 mg/100g and 2.38 mg/100g, respectively. Black and light brown sesame seeds exhibited the highest content of Fe (11.77 mg/100g) and Zn (7.70 mg/100g), respectively. We observed a significant positive correlation (P < 0.01) between the contents of Ca and Mg in both the different tissues and colored seeds. Moreover, a positive correlation was observed between Cu, Ca, and Mg contents in the different tissues and between Zn and Fe contents in mature seeds. Our findings may provide theoretical and technical guidance for sesame comprehensive utilization. [ABSTRACT FROM AUTHOR]

To give a better assistance to users in the understanding and analyzing of data, this paper proposes a new color mapping method based on global statistical and focal spacial characteristics, aiming at emphasis of both the global patterns and the boundary information of data. Our method employs Jenks natural break method to minimize control points in the color map and maximizes the color differences between boundary points and its neighbors to obtain the color napping. The effectiveness of our method Is verified via qualitative experiments and user researches on the 2D scalar field data. [ABSTRACT FROM AUTHOR]

The contents of polyphenols in tobacco leaves from different producing areas, different varieties and different parts in the tobacco area of Fujian were analyzed, in order to provide data reference for the production and quality evaluation of tobacco leaves. The contents of seven polyphenols including neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, caffeic acid, scopoletin, rutin and kaempferoside in 72 tobacco samples from X2F, C3F and B2F of CB - 1, Yunyan 87 and K326 in 12 counties of three producing areas in Fujian from 2020 to 2021 were determined and analyzed by high performance liquid chromatography (HPLC-DAD). Then, the distribution of polyphenols in tobacco leaves from different producing areas, different varieties and different parts were compared. The results showed that the contents of chlorogenic acid and rutin accounted for 75%-85% of the polyphenols in tobacco leaves in Fujian. There were great differences in the contents of polyphenols in tobacco leaves from different producing areas, different varieties and different parts. Among the main cultivated varieties in the tobacco area of Fujian, the total content of polyphenols in CB - 1 was higher than that of K326 and Yunyan 87. There was a significant positive correlation (R² =0. 948 6) between the total content of polyphenols in the three varieties and the sensory evaluation score of the unblended cigarette. The higher the total content of polyphenols, the higher the evaluation score of quality characteristics in sensory evaluation awarded. [ABSTRACT FROM AUTHOR]

Based on the purpose of UHMWPE fiber modification, various methods to improve the surface properties of UHMWPE fiber by plasma, radiation and graft polymerization were reviewed. Among them, UHMWPE fiber treated by plasma and reactive groups introduced by chemical reagent are widely used. At the same time, the common modification methods of UHMWPE and the research progress in recent years were introduced, and the development trend of UHMWPE fiber was prospected. Key words:UHMWPE fiber; method; modification; progress [ABSTRACT FROM AUTHOR]

The biosynthesis of gibberellin(GA) is a process of various enzymatic reactions and is closely related to plant development and stress response. To explore the distribution, structure and activity of sesame GA related genes, sesame genome sequence and transcriptomes from different tissues were studied based on bioinformatics methods. It showed that sesame had 32 GA related genes belonging to 7 different gene families, and these genes were distributed on all chromosomes except the chromosome 5. The protein sequence lengths of the different gene families were quite different. The CPS genes had the longest protein and contained 776 amino acid residues on average. The KAO proteins exhibited a great variation in size, varying from 401 to 834 amino acids. All the proteins encoded by GA related genes were predicted to be hydrophilic proteins. Compared with other species inclusing Ara-bidopsis, rice, soybean, grape, sorghum and tomato, the total number of GA related genes in sesame is not outstanding, but more CPS genes were observed in sesame. Evolution analysis indicated that sesame and tomato had a closer evolution relationship among the 7 species. In various sesame tissues, the 7 GA related gene families displayed quite different expression patterns. KS genes were highly expressed in seeds, stem tips and leaves. CPS genes were more active in pericarps and seeds, but were hardly expressed in stem tips and leaves. KAO and KO genes were constitutively and higly expressed in all tissues, while KS and GA3ox genes showed low levels of expression. Among the different tissues, the GA related genes generally showed higher activity in seed, then in root tip and in stem tip. This study provided important genetic information and theoretical references to analyze the characteristics of GA related genes in sesame and its role in different tissues. [ABSTRACT FROM AUTHOR]

Multi-color fluorescent fibers with different mass ratios co-doping of Eu(BPA)3phen and Tb(BPA)3phen were synthesized, and their characterization have been investigated by SEM, FTIR, TG-DSC and fluorescence spectroscopy. The result showed that the as-prepared fibers were in submicron scale with uniform diameters from 620 to 850 nm. IR spectra showed that doping rare earth complexes in PAN fibers had little effect on the absorption peaks of PAN fibers. TG-DSC result showed that compared with multi-color fluorescent fibers, the initial decomposition temperature of pure PAN was increased by nearly 10 °C doping with 2.5% rare earth complexes. The emission spectra of Eu/Tb co-doped BPA-phen complexes showed that with the increasing of Eu(BPA)3phen content, the red fluorescence emissions at 594 and 615 nm are enhanced gradually, while the green fluorescence emissions at 490 and 544 nm are totally decreased. Compared with the complexes, the position of predominantly emission peaks of Eu3+ and Tb3+ ions did not change after doping into PAN, but the luminescent intensity was decreased. According to the CIE color coordinate diagram, a series of multi-color fluorescent fibers could emit fluorescence from red to yellow then to green by adjusting the mass ratios of Eu and Tb complexes. [ABSTRACT FROM AUTHOR]

The laboratory is an important place of innovative activity and practice for teachers and students, but also an important mark of reflecting teaching and scientific research level in universities. The laboratory with high level is not only have advanced equipment, but also have the laboratory team with high level. Through the analysis of the current situation and existing problems of laboratory team in universities, the paper puts forward the strategy of strengthening the construction of laboratory team. A Four-in-one Construction Mechanism is proposed and used in our university, which involves rules and regulations, team construction, incentive and constraint, and training. These measures contribute to achieve canonical management, improve overall quality, encourage initiatives, and achieve sustained development of laboratory team. [ABSTRACT FROM AUTHOR]

Taking the 654 pig farmers of Funing, Jiangsu Province as a sample, we constructed an ordered Logistic model to analyze pig farmers' attitude towards the environmental benefits and its influencing factors. The result showed that variables, such as years of schooling, the proportion of pig farming's income that accounted for the total household income, years of farming experience, whether dealing the dead pigs with harmless treatment or not, pig farmers' abusing behavior, had significant influence on pig farmers' attitude to the environmental benefits, while all the policy environment factors are not significant. The result also showed that, at present, pig farmers' relatively positive attitude to the environmental benefits is not based on the high pig welfare cognition, but on the pursuit of economic interests. Therefore, with the development of our society, we must speed up the popularization of animal welfare, and implement the pig welfare policy gradually, and promote pig welfare-friendly breeding model, and finally solve the latent dangers of the livestock products from the source. [ABSTRACT FROM AUTHOR]

In this paper, the control method for missiles formation flight in the cooperative engagement was investigated based on variable structure control (VSC), adaptive control and nonlinear dynamic inversion control theory. Under the condition that the velocity and acceleration of the leader as well as the velocity of the follower were unknown, taking the relative velocity between the leader and follower as well as the acceleration of the leader as boundary uncertainties that can be estimated, a robust control law for missiles formation was proposed based on VSC, in which only the guidance information of relative position and relative velocity between missiles was required. The boundary layer method was adopted to eliminate the system chatting, and the setting method of boundary layer thickness was discussed to guarantee the formation control precision. The missile nonlinear dynamic system was divided into three subsystems from fast to slow based on singular perturbation theory. The extern disturbance acting on the missile system was taken into account and regarded as a boundary uncertainty in slow subsystem. Then a robust autopilot was designed based on adaptive variable structure control and nonlinear dynamic inversion control theory. Simulation results show that the missile autopilot can track the formation control command and the missiles formation can be realized. [ABSTRACT FROM AUTHOR]

Moisture content is an important quality index of drying products, which can be obtained by automatic weighing and analyzing its mass in the drying process. Compared with other moisture content measurement technology, the automatic weighing method has good versatility, high accuracy, and simple architecture. Relative humidity of drying air has significant effect on drying kinetics and product quality, while, for interior weighing devices, the humidity of hot air can easily be kept stable during drying process. In order to mitigate the effects of air velocity, equipment operating vibration, drying temperature, and other factors on the interior automatic weighing system of air-impingement drying, a new drying monitoring system based on Modbus communication protocol and RS 485 bus was designed. This system consists of five parts: an HMI (human machine interface) as master, a weighing system, a drying temperature control system, humidity control system, and air velocity control system. This paper mainly focuses on the measurement of material mass and moisture content. For the hardware of weighing system, strain gauge load cell and 0-5 V analog voltage transmitting instrument XST were applied in this system, and in order to implement temperature compensation to weighing system, the Pt100 type temperature sensor was adopted to sample the temperature of the weight sensor. Besides, signal acquisition, processing circuit with 8-bit microprocessor chip PIC16F1829 as core was designed, among which the analog transmission signal of weighting instrument is collected and converted by using 12-bit A/D chip TLC2543, and signal is converted by level conversion chip MAX487 to complete communication between master (HMI) and microprocessor PIC16F1829. And the weighting measurement range of this system is 0-2000 g and the resolving power is 1 g. For software design, median filtering algorithm, "shutdown-maintain-weight-start" automatic weighting procedures, linear calibration at different temperature sections, and load ranges were designed to eliminate the effect of accidental errors on automatic weighing, to weaken the effect of air velocity and equipment operating vibration on automatic weighing without affecting the drying process, and to reduce the effect of higher drying temperature and change of the temperature in wider range on automatic weighing, respectively. Through the above measures, automatic weighing accuracy was ensured effectively. In addition, the status of the slave controllers was incorporated into the run logic judgment of the system to guarantee the system's operational safety. This monitoring system could also realize the functions such as isochronal and instant measurement of material mass and moisture content, real-time display, and storage of experiment data in the drying process. After the completion of the system's hardware and software design, monitoring system' detection accuracy of mass and moisture content were tested in air-impingement dryer. Results of the weighing test showed that the maximum relative error to the mass of the samples is less than 0.7%. Then a series of drying tests on carrots were conducted. The results indicated that the error of the moisture content is within ±1.0% in drying process, which achieved the requirement of the on-line monitoring moisture content. The online air-impingement drying monitoring system designed in the current work is of great significance for evaluating and regulating the drying process for various materials, ensuring the product quality, and reducing the energy consumption and the labor intensity of drying operators. [ABSTRACT FROM AUTHOR]

The term "public memorial ceremony" has existed since the ancient times, but the meanings in the past and at present are different. In the past, it happens at the ranks of the state, the local and family for implementing, on the one hand, the social ethical ideology that attends carefully to the funeral riles of parents and follow them when gone with due sacrifices and, on the other, the hierarchical institution that distinguishes the priority in status. Modern public memorial ceremony arises under the influence of nationalistic ideology around the beginning of the 20th century. It is a reconciliation of the relevant traditions of both the West and our own. And today the practice subject per sc has gradually moved downward from the Central Government to the local and non governmental units, nomely, a way towards the public. The current form that has revived during 1980s conceives the necessity for further reform, which, however, does not influence the own historical advancement and the importance of the practice. [ABSTRACT FROM AUTHOR]

In order to research the laws of fissure evolution and methane migration in overlying strata, the authors found that fissure forms of mining overburden rock after mining can be represented by elliptic paraboloid zone through physical similarity simulation and numerical simulation. Based on key strata theory in strata control, considering mining height and distance from the first sub-key strata to coal seam roof, mathematical model of dynamic evolution of mining fissure elliptic paraboloid zone was established. By using environmental fluid mechanics, mass transfer theory, fluid mechanics, mining rock mechanics, equations of mining coal stress and pressure relief gas seepage, gas floating in longitudinal breaking fissure zone, and gas diffusion in transverse separating layer fissures zone were got, and then comprehensive control model of pressure relief gas seepage-floating-diffusion in elliptic paraboloid zone was built. Analyzing extraction mechanism of pressure relief gas in elliptic paraboloid zone, extraction technology of coal and methane was proposed. Through extracting pressure relief gas in Shanxi Tianchi Coal Mine, we got that mining fissure elliptic paraboloid zone was a storage area of pressure relief gas, where gas drainage system can be placed to achieve a good effect. [ABSTRACT FROM AUTHOR]

In order to obviously enlarge the coefficient of the seam permeability and reach a target of the high efficient gas drainage, a gas drainage technology of throughput fracturing permeability improvement by borehole in underground mine was provided. It was found that during the operation of the throughput fracturing, radial guided fracturing, peripheral guided fracturing, shearing fracturing, turning fracturing and others occurred on the max and min horizontal main stress directions. The gas migration channel with a high speed was formed under the displacement support compatibilization of the borehole surface wall. The site experiments showed that after the throughput fracturing conducted, in comparison with no measure conducted, the pure quantity of gas drainaged from a single borehole increased by 7-12 times, the volume fraction of gas drainaged increased by 4-5 times, and the attenuation coefficient of the borehole gas flow reduced by 1/4- 1/3. In comparison with the conventional hydraulic fracturing, the pure quantity of gas drainaged increased by 1.6-3.0 times, the volume fraction of gas drainaged increased by 1.2-2.0 times, and the attenuation coefficient of the borehole gas flow reduced by 1/5- 1/3. [ABSTRACT FROM AUTHOR]

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Objective: To investigate the physical and mental development of children of assisted reproductive techniques(ART) at 1-3 years, in the limited samples and the limited age range. Methods: A total of 266 ART children, including 106 twins, at 1-3 years were follow-up visited from February 2008 to February 2011. The control group comprised 129 children, including 84 twins, who were naturally bred. The neonatal outcomes, physical and mental development were evaluated. Results: Parent age in the ART children group was elder than that in control group. There were no significant differences in BMI, MDI and PDI between two groups of ART children and control, and between two twins' groups. A multivariate regression analysis indicated that the conception mode did not affect MDI and PDI. Conclusions: There are no significantly differences in the physical and psychomotor development between ART children and normal conception children in this study. [ABSTRACT FROM AUTHOR]

As an important part of historical studies, periodization is essential in understanding history in general. There had been two transitions in Chinese history in terms of periodization in the past over one hundred years. The first occurred in the late 19th and early 20th centuries, when modern Western progressive linear tripartite division of history via Japan took the place of the traditional Chinese historical compilation practices based on dynasties. During this process, the theory and practice of Japanese on Chinese history periodization played a decisive role, through which Chinese historians developed many theories by copying, imitating, or transforming, though not without insightful critics or alternative practices. The second transition, which was diverted to the Marxist historical periodization, germinated in the Chinese social history controversy in the late 1920s and early 1930s, and established itself after the socialist transformation in the late 1950s, surviving till today. In the making of the new scheme of periodization of the Chinese history in terms of social development theory, the Soviet version of Marxism is indispensable. With the establishment of the periodization system on the five modes of production theory, the emphasis on the research in Chinese historical periodization changed from the controversy of theory selection to the debate among Chinese Marxist historians. The two transitions are inevitable and in coincide with the theme of modern China, i. e. , to build an independent, prosperous, and modern nation. It influenced to some extent not only the path selection of China, but also the making of historical discipline, bequeathing some lessons worthy of intensive reflection. [ABSTRACT FROM AUTHOR]

The article discusses a study on the basic parameters of litters in fermenting-bed system of pig production to reduce the release of pollutant process by collecting litter samples and analyzing fermentation temperature, moisture, hydrogen ion concentration (pH), content of nitrogen and most possible number (MPN) of coliform group. High temperature in the bed can inhibit the growth of harmful microbes and coliform group MPN in litters can meet the requirements of feces pollution-free treatment.