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Nanoparticles exhibit excellent molecular adsorption capabilities and facilitate cellular penetration and intercellular molecule transfer by aiding in their movement across cell membranes. Additionally, nanomaterials serve as effective carriers for chemical drugs. Hydrogel, a polymer network system with a high water content that maintains a specific spatial shape, can be utilized to load various materials and drugs for biomedical applications. Periodontitis, one of the most prevalent chronic oral infectious diseases, poses a significant global health concern. However, current treatment modalities for periodontitis have several drawbacks. Nanoparticle-hydrogel composites, comprising nanoparticles embedded within a hydrogel matrix, offer a synergistic combination of controlled drug release from nanoparticles and prolonged retention properties of hydrogels, effectively addressing current treatment limitations. This paper provides an overview of nanoparticle-hydrogel composites, their properties, and their application in periodontitis treatment. Specifically, it delves into the definition, types, and unique qualities of these composites relevant to periodontal therapy. Furthermore, it highlights the computational modeling and simulation techniques utilized to optimize composite design and drug release kinetics. It concludes with a discussion of current challenges in the field and potential areas for future research.

Driven by the carbon peaking and carbon neutrality goals, Sichuan Province, with its abundant hydropower and renewable energy resources, possesses the feasibility to pioneer in constructing a provincial-level carbon-neutral power system in China. However, current grid planning lacks sufficient consideration for carbon emission related goals and constraints. To investigate the carbon emission evolution path of Sichuan Power Grid under the carbon neutrality goal, firstly, the distribution and development status of clean energy sources in Sichuan are clarified in this paper, and the low-carbon technology combination for Sichuan Power Grid's transition is determined. Then, load forecasting and other relevant factors are also combined to form boundary conditions for planning. Based on this, power source and grid planning research are carried out, exploring the two-stage evolutionary trajectory—transition period and formation period. Finally, employing the carbon emission flow theory, the carbon emissions at each phase are analysed, depicting the progressive realization of carbon neutrality in Sichuan Power Grid from the perspective of carbon emission flow.

Gas production from gas wells is affected by formation pressure and wellbore outflow during gas production. To increase the daily gas production and obtain smooth and efficient gas production gas wells, methods such as wellbore shut-in pressure recovery and foam injection and drainage for gas production are usually adopted. In this paper, the gas-carrying liquid model, capacity prediction model, and pressure recovery model are utilized to establish a full-cycle production prediction method for newly developed gas wells. Combining the initial development pressure, gas production, and water production parameters of the gas well, the gas production prediction is obtained for the next few years. Meanwhile, the implementation time of the forced drainage method is calculated and obtained.

workplace negative gossip refers to the informal and negative evaluation and discussion of thirdparty members who are not present when members of the organization communicate with each other. As a manifestation of workplace ‘cold’ violence, workplace negative gossip has the characteristics of concealment, difficulty in tracing back to the source, and rapid dissemination. The research on the antecedents of workplace negative gossip mainly focuses on the individual, interpersonal and organizational levels. The research on the negative gossip outcome variables in the workplace can be divided into its effect on employees’ cognition, emotion, behavior and performance and its mechanism. The research in this field is very important for seeking effective countermeasures to control workplace negative gossip and improving organizational management methods.

Reasonable location selection of shared bicycle parking points is an effective way to solve the current problem of shared bicycles. Considering the constraints such as the amount of shared bicycles, the number of parking points, and the capacity of parking points, a dual-objective bicycle-sharing parking point location planning model considering the cost minimization of both bike-sharing enterprises and travelers is established, and the simulated binary crossover operator and polynomial mutation operator are introduced to improve the NSGA-II algorithm to obtain the Pareto non-inferior solution set that satisfies both bike-sharing enterprises and travelers. The effectiveness of the model and the superiority of the improved algorithm are verified by the case. The results show that the model and algorithm can provide a reference for bicycle sharing enterprises in the location of parking points.

China In-depth Traffic Accident Survey (CIDAS) shows that two wheeler has the highest accident fatality rate, more than 38%, which is far more than cars and pedestrians. In this paper, the characteristics of traffic accidents in China, the types of two wheeler, and traffic characteristics of two wheeler are taken into account. There are typical hazardous scenarios in the case of crossing, longitudinal, turning, mixed, etc. In the existing collision scenarios design of cars and two wheeler, the testing methods of crossing and longitudinal have been basically mature. Therefore, combining with the functional testing of the current automobile active safety system, to recurrent the traffic scenarios of two wheeler objectively, the active safety test and evaluation scenarios of turning cars under the two wheeler traffic scenarios are designed. Test paths, test speeds, and impact position are proposed. it complements the test scenarios for active safety function.

Talent cultivation for primary training of aviation equipment majors has many modules, many categories, long class hours and cross-fields, and there are realistic difficulties in improving the teaching effect. After a number of training practices and explorations, it is found that collaborative training based on inter-college innovation has obvious advantages. In view of the real problems of aviation equipment professional primary training personnel training, based on the perspective of the advanced theory widely recognized in the education sector -actor network theory (ANT), we have explored the intercollegiate synergistic path with military colleges as the main body, which is of certain practical significance for further improving the comprehensive quality and efficiency of aviation security primary training personnel training.

The curriculum is the basic basis and carrier of educational and teaching activities, and it is the core of the digital transformation of education. With the continuous deep integration of digital technology in the curriculum and teaching, how to effectively deal with the impact and influence of the continuous innovation and breakthrough of digital technology on the curriculum and teaching, and better promote students’ inquiry and personalized learning has become an urgent problem in front of us. This paper focuses on the digital transformation of the background of the curriculum teaching issues, aviation maintenance management course as an example to carry out analysis and research, which can promote the deep integration of digital technology and curriculum teaching to provide reference and reference..

This study presents an in-depth analysis of the energy-saving bias in green technology innovation across 30 provinces in manufacturing from 2011 to 2021, utilizing a novel Malmquist-Luenberger multidimensional decomposition index based on the directional distance function. The research reveals that green innovation, characterized predominantly by energy conservation, plays a pivotal role in driving China's green total factor productivity. The impetus for innovation in energy saving is found to surpass that of emission reduction in manufacturing enterprises. Energy-saving biased green technology innovation, originating in economically advanced provinces, has gradually expanded to the northern region, and it encompassed the majority of provinces in China. This type of innovation serves as the primary driver of regional green innovation. The study also identifies a conspicuous spatial aggregation effect of energy-saving biased green technology innovation, linked intrinsically to the degree of industrial aggregation and the spatial correlation effect of innovation.

The ecological compensation system also implements the concept of intergenerational equity. By actively exploring and perfecting the ecological compensation system, resource-based cities can carry out ecological restoration and restoration in time while developing oil and gas resources, so that the carrying capacity of ecological environment can support the benign development of social economy and environment in resource-based cities, which is of great significance not only to resource-based cities, but also to the sustainable development of the entire oil and gas resources industry. Taking ecological compensation as the breakthrough point, this paper points out the necessity of oil and gas resources tax system from the perspective of ecological compensation, and puts forward some ideas and suggestions, such as levying environmental protection tax, establishing the legal system of ecological compensation for oil and gas resources development, improving the integrity and rationality of oil and gas resources tax system and other guarantee mechanisms.

This study determined the occurrence, removal and environmental risk assessment of 24 multi-class pharmaceuticals and personal care products (PPCPs) in wastewater treatment plants (WWTPs) of Jiangsu Province, China. Solid phase extraction was used for pre-concentration of the samples with ultra-performance liquid chromatography coupled with tandem mass spectrometry analysis following. Results indicated that the maximum concentrations of the PPCPs varied between 2.15 ng/L and 6234 ng/L in influents and effluents. Quinolone antibiotics, macrolide antibiotics, cephalosporin antibiotics, lotions and other drugs were detected more commonly. Above the calculation of the risk quotient, clarithromycin and sulfamethoxazole showed high potential environmental risk for acute toxicity.

The purpose of this article is to investigate the effect of different bending angles and traction directions of the traction arm on the stability of the titanium plate for bone-anchored maxillary protraction (BAMP). The titanium plate models with different bending angles of the upper and lower jaws were modelled in three dimensions, where the bending angles were 90°, 120°, 135°, 150°, 180° and recorded as U1-U5 and L1-L5 respectively. Finite element analysis was performed on the titanium plates with different structural parameters to complete the structural design selection study of the titanium plates. The displacement limit was defined and different angular tensile forces were applied to record the equivalent stress and displacement of the titanium plates under each working condition. A total of 120 sets of orthogonal simulation tests were designed, which showed that the stress values at U2, U3 and U4 are smaller at traction angles of 135° (66.152 MPa), 155° (59.015 MPa) and 175° (55.589 MPa) respectively. The displacement is correspondingly smaller at tensile angles of 135° (0.0073 mm), 150° (0.0056 mm) and 160° (0.0058 mm). L2 has the smallest stress value (50.491 MPa) and displacement (0.0062 mm) at a tension angle of 120°. Therefore, it is recommended to design a titanium plate with a mandibular traction arm bending angle of 120° for BAMP, and the traction arm bending angle of the maxillary titanium plate can be flexibly designed according to the clinical traction direction.

“New Business” is a new Economic and Management Education concept under the new liberal arts. The Ministry of Education's “Declaration on the Construction of New Liberal Arts” pointed out that one of the starting points to promote the construction of new liberal arts is to improve the quality of the courses. Course construction is the foundation of the construction of majors. It is important to strengthen the construction of the professional introductory courses group in combination with the current conditions and practice of the financial majors of Canvard College. Based on this, this paper raises some problems in constructing introductory courses group and proposes innovative initiatives for designing concepts, frameworks and models as ideological and political construction of curriculum, optimization of teaching contents, reform of teaching mode, reform of teaching methods and reform of teaching appraisals.

With the development of urban roads and the growth of traffic flow, large-scale congestion often occurs. The long time-consuming urban road traffic makes drivers very annoying. This is the main reason for using simulation tools to analyze and optimize urban road traffic flow. Intelligent body modeling and simulation has been regarded as a reliable and powerful tool in the field of traffic simulation. This paper uses Anylogic software based on intelligent modeling and simulation to solve the traffic flow optimization problem in a congested area in Tianjin. The simulation results show that by changing the display time of the traffic lights in the road network, the vehicle travel time in the system is reduced from 145.46 seconds to 132.31 seconds. After 300 iterations of experiments, it was determined that the vehicle’s travel time in the system reached the optimum when iterated 73 times.

This research conducted a thermal compression deformation test on two GH4169 alloy samples with 5.40wt% and 5.21wt% Nb contents respectively, under deformation temperatures ranging from 900°C to 1030°C and the strain rates of 0.04s-1, 0.08s-1. Data from the deformation test were used to study the effects of deformation temperature and strain rate on the microstructure, δ phase morphology, and δ phase evolution of both alloy samples, so as to reveal the structural evolution mechanism. The results show that the long needle-like δ phase in the alloy microstructure with high Nb content undergoes deformation fracture and decomposition fracture during deformation and compression under high temperature, with the fracture decomposition temperature being 990°C. Moreover, microstructures of alloys with low Nb content were dominated by granular δ phases; as the deformation temperature increases or the strain rate decreases, the content of the δ phase gradually decreases, causing the alloy’s dynamic recrystallization grain size and dynamic recrystallization volume fraction to gradually increase from deformation twins at low temperatures to complete recrystallization at high temperatures.

The construction industry is the driving force and pillar of my country’s economic development. In recent years, due to the increasing difficulty of construction and long construction period, the traditional construction technology safety management mode is no longer suitable for modern construction projects. Construction safety accidents also occur frequently and threaten The personal safety of construction workers has caused a serious negative impact on construction enterprises. The application of BIM technology and building information system has created a new management model for construction safety management in the construction industry, greatly improving the level of engineering construction safety management, and also marking the construction industry's march toward a new era of technical information.

The research on energy consumption quota of metrology laboratory is an important part of building energy conservation from the perspective of total amount control. Through the research on the investigation method of basic energy consumption data, the type of quota index and the determination method of quota level. The analysis shows that the metrology laboratory adopts the method of unequal proportion classified sampling survey to obtain the basic data of energy consumption, adopts the energy consumption per unit area, considers the correction of energy consumption time and the proportion of auxiliary room area as the quota index, and uses the quota level method to determine the limit value, reference value and advanced value of energy consumption quota, which is fair, scientific and feasible.

The effect of high buoyancy forces due to density contrast between the fluids on either side of the vent on the discharge coefficient Cd is taken into account in the laboratory. Salt water experiments are conducted at small scale in a large fresh water tank with saline to generate buoyancy force. In non-Boussinesq cases, a larger discharge parameter Γd at the vent may make plume-like flow contract further with a smaller value of the discharge coefficient. A nearly twofold time in the non-dimensional form for draining light fluid fully out of the space is observed comparing with time predicted with a constant value of Cd = 0.6 for simple draining flows. A displacement flow theoretical model with virtual source correction at the initial position of an internal source is developed to reveal a time-dependent movement of the layer interface, and the oscillatory amplitude of the interface overshooting during the transient period is found to depend on the two dimensionless geometrical parameters Λ and Θ.

During the operation of overhead conductors, conductors are corroded to varying degrees by the smoke and dust, harmful gases from factories around the lines, or in corrosive salt fog atmosphere in coastal and island areas, as well as humid and hot weather conditions. In this paper, through the study of the corrosion mechanism of the conductor, the types of the corrosion are analyzed, and the factors leading to the corrosion and the corrosion process are analyzed by selecting the steel cored aluminum stranded wire, so as to provide theoretical basis for the development of anti-corrosion wire and the judgment of corrosion detection.

The single-factor evaluation method, improved Nemerow index method, fuzzy mathematical synthesis evaluation method and comprehensive nutrient status index method were used to evaluate the water quality of the Zijiang River in summer, and to analyze the applicability of the evaluation methods. The results show that: (1) The Zijiang River is heavily polluted with nitrogen and TN is the main pollutant in the summer. The overall nutrient status index is 34.33, which is not eutrophic. (2) The single-factor evaluation method is simple and suitable for rapid identification of excessive pollutants, but cannot reflect the water quality. the Nemerow index method takes into account the weight of each evaluation factor in the river water quality, and is suitable for making a comprehensive evaluation of the river water quality, but has a certain degree of subjectivity when classifying the water quality. The fuzzy comprehensive evaluation method is suitable for reflecting the influence of different evaluation factors on water quality by calculating the weight and membership degree of each evaluation factor, but the calculation is complicated.The Integrated Nutrient Status Index method is suitable for determining whether eutrophication is occurring in a water body and cannot determine the water quality category.

A swivel cable-stayed bridge over the existing railway is a span across the existing railway. The recommended scheme for the main bridge is (128 + 388 + 128) m steel mixed composite beam swivel diagonal pull bridge with span. The cables of the diagonal pull bridge are arranged according to the fanshaped central double cable plane, taking into account the mechanical performance and aesthetics. The bridge structure adopts semi floating system. The concrete swivel diagonal pull bridge is adopted in the comparison scheme. The design of the bridge is three spans and (138 + 268 + 138) m prestressed concrete box girder is adopted. The cables are arranged according to the central double cable plane, and the bridge composition adopts the consolidation system. Considering the needs of bridge operation and maintenance in the later stage of the bridge, when the dead weight of concrete diagonal pull bridge is within the ideal range, the concrete swivel diagonal pull bridge can be preferred. In order to calculate the dead weight of the selected bridge, the author uses the finite element software to model the whole bridge and calculate the weight of the bridge. The results show that the dead weight of the concrete swivel diagonal pull bridge is too large, which has exceeded the maximum bearing capacity of the existing spherical hinge. In order to continue to use the concrete swivel diagonal pull bridge scheme, it is necessary to optimize the design of the concrete swivel diagonal pull bridge scheme.

In order to study the influence of prestress on cantilever deflection and construction linear control of continuous rigid frame bridge in construction stage, this paper introduces the significance of continuous rigid frame bridge’s linear control, the calculation principle and deflection influence analysis of vertical formwork elevation in cantilever construction. According to a specific continuous rigid frame bridge, this paper use the finite element software to simulate and calculate the deflection of prestress to the cantilever construction of continuous rigid frame bridge. The influence of friction coefficient between prestressed steel bundle and bellows and prestress loss on cantilever deflection and construction line control of continuous rigid frame bridge is also analyzed, furtherly brings out the solution to deal with the problems due to the change of prestress.

Distributed generator (DG) is widely used and applied due to the energy and environment issues. Distributed photovoltaic generation is a typical kind of DG. Its output power is random and fluctuant, which has great influence on the safe, stable and economic operation of power system. Thus it is necessary to identify the power generated by the distributed photovoltaic generation. This paper proposes a power identification method based on BP Neural Network. The sample data comes from simulation by PSCAD and consists of current and active power that are measured in the branch of distributed network connected with DG and active power generated by the DG. The training is based on Matlab. Simulation results verify that the BP Neural Network can identify active power of DG accurately.

A novel method to predict transformer fault by forecasting the variation trend of the dissolved gases content is proposed. After the content of each feature gas, such as hydrogen and methane, is obtained by the proposed forecasting model, the fault type can be diagnosed by the dissolved gas analysis (DGA) technologies. Firstly, the GM (1,1) grey model with unequal time interval is introduced to generate a general forecasting model for each feature gas. The introduced grey model with unequal time interval will enforce no constrain on the historical measurement data. Consequently, the time intervals of the two adjacent measuring points can be either constant or variant. To address the deficiency that the existing grey model is unable to describe the fluctuation of the predicted object in time domain, the Markov chain is introduced to improve the accuracy of the grey forecasting model. An adaptive method to automatically divide the state space based on the number of states and the relative error of the grey model is presented by using Fibonacci sequences. Practical measurements are used to verify the accuracy of the proposed forecasting model. The numerical results show that there is high probability (86%) that the proposed grey-Markov model acquires a smaller prediction residual as compared to the original GM(1,1) grey model.

With the continuous expansion of the scale of the power grid and the continuous increase in the proportion of new energy and power electronic equipment, higher requirements are placed on the basic data of the online security analysis of the power grid. This paper proposes a multi-source data integration system for large power grid operation. It studies the rapid interaction and intelligent integration of multi-source heterogeneous information such as offline and online models, breaking the technical application barriers of various types of data, and quickly generating real-time power grid model. The analysis model provides a reliable data basis for the online analysis of the power grid. Finally, based on the PSASP simulation software, the correctness and effectiveness of the multi-source data integration system of large power grid are verified.

The influence of steel fiber and polypropylene fiber mixed on compressive strength of high performance concrete (HPC) was studied. The steel fiber content (0.5%, 1.0%, 1.5%, 2.0%) (volume fraction, the same below), polypropylene fiber content (0.05%, 0.1%, 0.15%, 0.2%) and length (5mm, 6.5mm, 12mm, 18mm) were studied by L16 (45) orthogonal test for 28d ages, the range analysis and variance analysis of the test results are carried out, and the prediction model of compressive strength of hybrid fiber reinforced concrete was established. The results show that: The significant influence factor of concrete compressive strength is the volume fraction of polypropylene fiber, while the length of polypropylene fiber and the volume fraction of steel fiber are not significant; the concrete compressive strength with polypropylene fiber shows negative hybrid effect; The prediction model of compressive strength of hybrid fiber reinforced concrete has high accuracy, and the average relative errors is 2.96%.

The research on cold fusion phenomenon has been in the past 30 years. Based on the research results of the predecessors, this article comprehensively describes the research results of the predecessors on the cold fusion phenomenon, and discusses it theoretically and experimentally. From the perspective of thermodynamics, this paper proposes to charge the palladium wire with hydrogen at low temperature to increase the frequency of abnormal heat generation, and gives a calculation formula for the hydrogen charging rate of the palladium wire. At the same time, a theoretical solution model for the isotope effect on the abnormal heat release phenomenon is proposed.

Supercharging in the vicinity of a borehole is an important factor that affects formation damage and drilling safety, and the filter cake growth process has a significant impact on supercharging in the vicinity of the borehole. However, existing models that predict pore pressure distribution overlook dynamic filter cake growth. Thus, an analytical supercharging model was developed that considers time-dependent filter cake effects, and this model was verified using a two-dimensional numerical model. The influences of filter cake, formation, and filtrate properties on supercharging were investigated systematically. The results indicate that time-dependent filter cake effects have significant influence on supercharging. Supercharging increases in the early stage but decreases over time because of the dynamic growth of filter cake, and the supercharging magnitude decreases along the radial direction. Because of filter cake growth, the magnitude of supercharging falls quickly across the filter cake, and the decreased magnitude of pore pressure caused by the filter cake increases. Supercharging in low-permeability formations is more obvious and the faster rate of filter cake growth, a lower filtrate viscosity and faster reduction rate of filter cake permeability can help to weaken supercharging. The order of importance of influencing factors on supercharging is overbalance pressure > formation permeability > formation porosity ≈ filtrate viscosity > filter cake permeability attenuation coefficient > initial filter cake permeability control ratio > filter cake growth coefficient > filter cake porosity. To alleviate supercharging in the vicinity of the borehole, adopting drilling fluids that allow a filter cake to form quickly, optimizing drilling fluid with a lower filtrate viscosity, keeping a smaller overbalance pressure, and precise operation at the rig site are suggested for low-permeability formations during drilling.

With the widening of the application fields of polycondensation polymers, many types of modifiers have been used to modify the molecular structure of polycondensation polymers. In recent years, more and more researchers have focused on the study of the molecular structure modification of polycondensation polymers and gradually ignored the research on the synthesis methods and properties of polycondensation polymers. This review covers the synthesis strategies of four common polycondensation polymers in the market, including polyamide (PA), polycarbonate (PC), polyester (PET), and phenolic resin. Two general synthesis routes of PET starting from dimethyl terephthalate and terephthalic acid were suggested; the synthesis strategies of PA-66 and PA-6 were discussed; the synthesis methods of aromatic PC from bisphenol A polycarbonate by phosgene or transesterification were summarized; the general synthesis methods of thermoplastic phenolic resin and thermosetting phenolic resin were discussed. In addition, some new synthesis methods and modification methods of these polycondensation polymers were reviewed. Besides, the properties, application, and market value of these polycondensation polymers were summarized. It is hoped that it will be helpful for the new synthesis of polycondensation polymers.

Population spatial data can more truly express the actual distribution characteristics of the population, and provide data support for the regional environment and population development. Use Shandong Province as the research area, township-level census data, revised DMSP/OLS night-time data, and Globaland30 land cover data as data sources, partitions based on population agglomeration, and uses a stepwise regression method to build a population data spatial model. Use the model to simulate population density with a resolution of 100m. The experimental results show: Stepwise regression model good precision, the average relative error was 23.56%, and Root Mean Square Error, Mean Absolute Error are better than the other two public datasets. The simulation results are better than the two public datasets.

Wushu course is a basic content in physical education teaching in colleges and universities. The teaching content of Wushu course is mainly routine teaching. Because Wushu routine is composed of many individual movements, the direction, route, rhythm and body posture are complicated and different from the students’ daily activities and other sports teaching materials, many students feel that Wushu is “difficult to learn” and “forget quickly “. In order to overcome the phenomena of “difficult to teach “,” difficult to learn” and “forget quickly “, we must deeply study the teaching methods in order to improve the teaching effect of martial arts. Demonstration teaching method is the main teaching method used in Wushu teaching, and it is also one of the effective ways to improve the teaching effect of Wushu. As multimedia teaching is more and more used in teaching, demonstration teaching method also has more new teaching methods. [1] This paper analyzes the effect of martial arts teachers in the teaching process through the experimental study of three classes in the martial arts curriculum of physical education major in Dehong Teachers College. In order to study the teaching effect of different intuitive teaching methods in martial arts class.

The article reviewed migration, degradation, toxicity, and distribution of microplastics, which was focused on data enumeration of emission samples from countries around the North Pacific Ocean, South Atlantic Ocean, and Circumpolar oceans. Microplastic particles are easily absorbed by animals and spread to the whole food chain, and they have been confirmed to exist in the human body. It was well established that high abundance microplastics were trapped by ocean currents and accumulated in surface and sediment in convergence zones of the five subtropical gyres. While microplastic itself leaches out the toxin in the seawater, synergistic effects between microplastic and other pollutants increase microplastic toxicity for organisms. The monomers of 16 out of 55 plastic polymers were carcinogenic and mutagenic or toxic for reproduction. Additives used in the process are also dangerous polypropylene (PP), and polyethylene (PE) prefer to sorb persistent organic pollutants (POPs) and have an extremely slow rate of desorption, which form synergic effects and increase the toxicity of microplastics (MPs). For other plastic polymers, the sorption and desorption of pollutants by MPs depends on the concentration of POPs, so the toxicity of MPs varies with the content of pollutants. But for some types of MPs and POPs, the concentration of POPs controlled by microplastics also can decrease the lethal toxicity of POPs. Higher concentrations of MPs in the seawater cause larger MPs consumptions of marine organisms, especially in polar regains that have the highest MPs concentrations.

Silica aerogels are lightweight, highly porous nanomaterial with extremely large internal surface area but fragile and brittleness. To enhance the applicability of aerogels, fiber reinforced silica aerogel insulation blocks are prepared by frothing method. Polyurethane emulsion acts as binder whereas polyethylene (PE) fiber and polyurethane (PU) fiber is used as reinforcing phase. The effect of polyethylene fiber and polyurethane fiber on the performance of composites were characterized by material's chemical microscopic morphology, compression performance, recovery performance, surface area, thermal conductivity and hydrophobicity. The research results show that the prepared PU fiber reinforced silica aerogel insulation block has excellent comprehensive performance. The water absorption rate of decreased from 19.35% (0 phr, PU fiber) to 6% (20 phr, PU fiber), and comprehensive rebound rate was increased by 97.83% at 20 phr PU fiber compared with pure insulation block (83.88%). Meanwhile, the dimensional stability of the composite aerogel block is above 96%. PU fiber reinforced silica aerogel insulation block has light weight, good hydrophobicity and good thermal and mechanical properties, so it has a wide range of application prospects in the field of insulation.

The purpose of this article is to simulate the TVOC release of building materials in the environment chamber. Based on the theory of mass transfer, a three-exponential decay empirical model is proposed. The validity of the model is verified by experimental data and comparison with the classical model. From the fitting results, the new model is more consistent with the experimental data.

Cet article offre un nouveau point de vue sur l’enseignement de la littérature en didactique du FLE, notamment avec les apprenants sinophones. Il s’agit d’introduire une perspective cognitive dans la lecture littéraire. L’objectif est d’une part, d’établir une interaction et une intercompréhension entre les systèmes langagiers de la langue en cours d’apprentissage et de la langue maîtrisée par les apprenants sinophones, et d’autre part, de construire le sens du texte littéraire, en recourant à la fois aux pensées de l’auteur et au vécu du lecteur. Dans cette optique, les textes littéraires sont considérés comme un support pédagogique où beaucoup de possibilités linguistiques, interculturelles et motivationnelles s’inscrivent. Et pour les apprenants sinophones, ils deviennent aussi un étayage pour surmonter les décalages linguistiques et culturels entre la France et la Chine.

In recent years, landslide disasters have occurred frequently, making the evaluation of the susceptibility of landslide hazards a major difficulty and hot topic in current research. The current research focuses on the use of statistical models or information models to analyze landslide hazards. However, the accuracy is not high. We first study the mechanism of landslide geological disasters. Based on this, combined with multi-source geological data, a linear rupture plane method (LRP) is employed to construct the landslide hazard evaluation system. LRP regards the failure surface of the slope as an approximate plane and the section as an approximate straight line. It uses the principle of limit equilibrium to calculate the safety factor of slope. In the paper, the Ziyang area with frequent landslide disasters is taken as the research area. Choosing landslide hazard points in Ziyang County as the sample data, we select seven factors including slope height, slope angle, soil bulk density, soil cohesion, internal friction angle, precipitation intensity and seismic intensity as influencing factors. Based on the LRP, we construct an evaluation system to divide the landslide into three grades: high-risk area, low-risk area and safe area, which provides effective technical support for the early warning and prevention planning of landslide disasters.

Research on hospital logistics management is conducive to improving the efficiency of logistics operations and promoting the economic development of the hospital. In order to solve the problem of logistics management affected by a large number of uncertainties and multi-state factors, a set of 12-factor research index system was constructed from three aspects: basic skills, element skills, and task skills, and at the same time, the level of evaluation indicators was determined. In the interval, a research method of hospital logistics management based on cloud model is proposed. And according to Monte Carlo simulation, find out specific sensitive factors. Finally, the effectiveness and feasibility of the method is verified through the logistic operation and maintenance examples of 4 Grade-A public hospitals in Wuhan.

The research content of this paper is to improve the high temperature fault problem of the wind power inverter and optimize the processing process of the high temperature fault problem. In order to solve the high temperature fault problem, the water-cooling system of inverter is analyzed in detail by using the function analysis, cause and effect analysis and object field analysis in the invention problem solving theory (TRIZ theory). At the same time, combined with the invention principle of TRIZ theory and the standard solution, seven different solutions are finally obtained. Based on the ECRS principle, the general process of high temperature fault problem treatment is simplified through continuous optimization and improvement.

Combining both geological and petrophysical properties, a reliable rock typing scheme can be achieved. Two steps are included in rock typing. Step 1: rocks are classified into lithofacies based on core observations and thin sections; Step 2: lithofacies are further subdivided into rock types according to petrophysical properties such as MICP (Mercury Injection Capillary Pressure) and K-Phi relationships. By correlating rock types to electrofacies (clusters of log data), we can group the target formation into 12 rock types. Then it is possible to predict the distributions of rock types laterally and vertically using wireline logs. To avoid the defect of the classical J-function saturation model that includes permeability which is quite uncertain especially in carbonate rocks, a modified J-function was created and used in the paper. In this function, water saturation is simply expressed as a function of height above free water level for a specific rock type. Different water saturation models are established for different rock types. Finally, the water saturation model has been successfully constructed and verified to be appropriate.

As one of the important components of the joint connection in the steel-concrete structure, the embedded parts of straight anchors have a great influence on the safety performance of the structure. People have different opinions on the mechanism of the force of the embedded parts, and the calculation method of the bearing capacity of the embedded parts is also different. In this paper, the research on the theory of the sheared and tension-sheared parts of embedded parts of straight anchors in the previous literature and the current norms is conducted, and the existing calculation methods of the ultimate bearing capacity are compared. The calculation method is compared with the experimental results, and the theoretical verification analysis is performed. The research results show that: Nowadays, the calculation of the shear capacity of the anchored parts of the anchors is conservative, and there are some factors that have not been considered, so they are much smaller than the actual bearing values. For the shearing ability, the two are the calculated values whcih are close to the correlation between the pulling and shearing. When the embedded parts are damaged, the anchors fully give full play to the tension-shear effect, which can be used in the project.

ε-Poly-L-lysine (ε-PL) is a natural food preservative with high safety to humans and a wide antimicrobial spectra. It was found that ε-PL could form precipitates when it contacted to Cu(II) and Zn(II). Thus in this study, two complexes of ZnCl2 and CuCl2 with ε-poly-L-lysine having molecular weights between 2 and 5 kDa were prepared and characterized by elemental analysis (EA), atom absorption spectrometry (AAS), chlorine assay, etc. The results show that the compositions of two complexes can be expressed as [ NH-(CH2)5-CO ] 2n•(ZnCl2)n•2nH2O and [ NH-(CH2)5-CO ] 2n•(CuCl2)n•2nH2O (n=6-18), respectively. The results of FT-IR reveal that the formation of Zn-N and Cu-N coordination bonds. X-RD patterns indicat that the two complexes are new phases different from the raw ε-PL material. On the basis of TG-DTA curves, the complexes have a coordination reaction. From the results of the bacteriostatic test, ε-PL-Zn(II) and ε-PL-Cu(II) have similar antibacterial activity to ligand ε-PL.

Thermal performance is considered to be a key measure in building sustainability. One of the technologies used in the current building sustainable design is the high thermal mass techniques. The application of this type of technology is widely used in traditional architecture. The paper aims at studying the effect of both high thermal insulation and high thermal mass techniques in buildings dynamic behaviour in Dry-Hot and Dry-Cold Climate. The two techniques can lead to conflicting requirements when considering winter and summer conditions. Therefore, it is necessary to identify insulation measures that conserve the mass dynamic behavior. Experimental investigations were carried out on a single - family house to characterize the behavior of one room with high thermal mass in different seasons. Thermal simulations made it possible to explore different retrofit configurations. Different thermal mass and thermal insulation were compared on internal surface temperature. The analysis shows that the most suitable intervention is both high thermal insulation and high thermal mass techniques, and the decrease of the absorption coefficient of the outer surface is beneficial to improve the overall level of solar radiation.

In rotary swaging – an incremental cold forming production technique to reduce the diameter of axisymmetric parts – the material flow can be assumed to be predominantly axial and radial. The actual ratio of this axial and radial flow influences the mechanical properties and especially in tube forming the final geometry. It is known that during mandrel free infeed rotary swaging of tubes the wall thickness changes. The change is depending on the process parameters like incremental and cumulated strain. Hence, the ratio of axial and radial material flow changes. Consequently, the analysis of the wall thickness of rotary swaged tubes enables fundamental insight how to control the material flow direction. In this study, the infeed rotary swaging process of steel tubes with different wall thicknesses from 3 mm to 7 mm and rods were investigated with FEM under two feeding velocities. The axial and radial material flow and the resulting geometry were studied by the relative wall thickness. It could be seen that the relative wall thickness was affected by the feeding velocity as well as the initial wall thickness. The findings of the simulation were validated by rotary swaging experiments.

Aiming at answering the question that low tap service life of ordinary tapping and bad thread quality on particle-reinforced metal matrix composite SiCp/Al, the reason of question and the mechanism of low-frequency torsional vibration tapping are analyzed. The experiments were carried out to compare the tap service life and the thread quality of vibration tapping with ordinary tapping without cutting fluid. It indicates that vibration tapping could make tapping torque reduce greatly, the tap service life could be prolonged twice comparing with continuous tapping without cutting fluid, and could ensure the good thread quality. Moreover, it promotes metal matrix composite’s further application.

The temperature control system is an indispensable key system for the thermal vacuum test. It is used to simulate the infrared heat flow environment of the spacecraft in orbit. In order to improve the stability and reliability of temperature control, this paper designs and develops a thermal vacuum test temperature control system based on the Modbus RTU serial communication protocol on the LabVIEW platform. The system combines the flexibility of software development on LabVIEW platform and combines the stability of serial communication with controller. This temperature control system has been used in thermal vacuum test, the control effect of overshooting within 1°C and temperature control accuracy within ±0.2°C. The system has high stability, which achieves the expected goal.

A new PD-like control law is proposed in this paper to control a multistable impacting system. This control law can switch the system from a current, undesired state to a desired one by using the differences of the displacement and velocity between the current and desired states. The control law can control the multistable system without affecting its original dynamics, and its stability is proved by using the Lyapunov direct method. Numerical results are compared with the results obtained by using the intermittent control studied in [1]. The proposed PD-like control shows a better performance in terms of the smoothness of its control signal, which is easier to be implemented in practical applications.

Stick-slip oscillation in drill-string is a universal phenomenon in oil and gas drilling. It could lead to the wear of drill bit, even cause catastrophic failure of drill-strings and measurement equipment. Therefore, it is crucial to study drilling parameters and develop appropriate control method to suppress such oscillation. This paper studies a discrete model of the drill-string system taking into account torsional degree-of-freedom, drill-string damping, and highly nonlinear friction of rock-bit interaction. In order to suppress the stick-slip oscillation, a new proportional-derivative controller, which can maintain drill bit’s rotation at a constant speed, is developed. Numerical results are given to demonstrate its efficacy and robustness.

FP-Growth algorithm is an association rule mining algorithm based on frequent pattern tree (FP-Tree), which doesn’t need to generate a large number of candidate sets. However, constructing FP-Tree requires two scansof the original transaction database and the recursive mining of FP-Tree to generate frequent itemsets. In addition, the algorithm can’t work effectively when the dataset is dense. To solve the problems of large memory usage and low time-effectiveness of data mining in this algorithm, this paper proposes an improved algorithm based on adjacency table using a hash table to store adjacency table, which considerably saves the finding time. The experimental results show that the improved algorithm has good performance especially for mining frequent itemsets in dense data sets.

The generation cost, carbon emissions and customers’ satisfaction are considered in this paper. On the basis of this, the multi-objective and low-carbon economic dispatch model with wind farm, this considers demand response, is established. The model user stochastic programming theory to describe the uncertainty of the wind power and converts it into an equivalent deterministic model by using distribution function of wind power output, optimizes demand side resources to adjust the next day load curve and to improve load rate and absorptive capacity of wind power, introduce customers’ satisfaction to ensure that the scheduling scheme satisfies customer and integrate the resources of source and load to unify coordination wind farm access to network and to meet the requirements of energy saving and emission reduction. The search process of artificial fish school algorithm introducing Tabu search and more targeted search mechanism, an multi-objective improved artificial fish school algorithm is proposed to solve this model. Using the technique for order preference by similarity to ideal solution (TOPSIS) to sort the Pareto frontier, the optimal scheduling scheme is determined. Simulation results verify the rationality and validity of the proposed model and algorithm.

Multi-level approach has been used to simulate the thermal deformation of aluminium alloy at different temperature and strain rate. The crystal plasticity model is extended in the finite element method and the thermal behaviour is integrated in the constitutive equations. Moreover, the damage evolution is also reflected in the simulation using continuum damage mechanics model. Thus, the void evolution and thermal effect could both be shown in the simulation. A new shear strain rate model is constructed with the thermal activated mechanism to describe the rate dependent behaviours during tensile test. The thermal parameters are determined in a fitting test of representative volume element to compare with the experimental data. The results prove that the mechanical tensile behaviour of 5052 aluminium alloy could be well described at different temperatures. The damage evolution process is expressed by the stress concentration and strain concentration in the finite element simulation, which are also confirmed by the experiments.