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Insulation materials play a crucial role in reducing a building’s energy demand and carbon emissions. To optimize building lifecycle costs and reduce carbon emissions, this study developed an energy consumption simulation method specifically for the conceptual design phase of buildings to assess the impact of insulation material selection. Through this method, the study obtained the energy performance of buildings and calculated the lifecycle cost and carbon emissions data. A comparative analysis of different design schemes and material choices was then conducted. The results indicate that a rational selection of insulation materials can significantly reduce related costs by 75% and carbon emissions by 81%. The significant variations in cost and carbon emissions among different conceptual design styles further emphasize the importance of using simulation methods in the early stages of building design to optimize both cost and carbon emissions.

Atherosclerosis is a disease that occurs in blood vessels and is also responsible for numerous diseases, including coronary heart disease and cerebral infarction. It can affect the function of many organs of the human body, cause great damage to human health, and the incidence is high in the middle-aged and elderly people. The pathogenesis of atherosclerosis is very complex, which is the result of inflammation caused by lipid deposition on the blood vessel wall. At present, aspirin is the most commonly used drug in clinic. It has strong anti-inflammatory and antithrombotic effects. In addition, high density lipoprotein, or HDL, can transport cholesterol in the blood vessels, and it does exert some influence on the treatment of atherosclerosis, but the exact therapeutic pathway is still the subject of ongoing research. This paper illustrates the pathogenesis of atherosclerosis, and introduces the mechanism and feasibility of two therapeutic modalities, aspirin and HDL, and gives a reasonable future research direction.

With the continuous increase of the total amount of municipal solid waste in China, waste management has become an urgent matter. To address this challenge, the Chinese government recently launched a new waste management system. Previous studies have confirmed the effectiveness of incorporating intrinsic motivation factor into the theory of planned behavior for predicting green behavior, however, the interaction between variables in the model has not been fully explored in the Chinese context. Therefore, this study extended the theory of planned behavior with moral norms to evaluate the household waste management behavior of Beijing residents. With 342 residents as samples, hierarchical multiple regression was used for analysis. The empirical result showed that all determinants in the extended model positively predict behaviors. Moral norms were the most important determinants of behavior, followed by subjective norms, and then perceived behavioral control and attitude. In addition, moral norms played a mediating role in the influence of attitudes and subjective norms on behavior. These findings will help expand and improve understanding of the key factors affecting residential waste management, make reasonable recommendations for environmental protection and sustainable development.

Comprehensive improvement of the marine environment, as one of the important measures for ecological restoration of national land space, is the inheritance and development of ecological restoration. By integrating the perspective of marine ecosystem service functions and comprehensively applying various restoration measures, we are committed to optimizing the development pattern of blue national land space, improving the efficiency of natural resource utilization and improving the quality of the ecological environment, in order to collaboratively achieve the ultimate goal of intensive and efficient production space, livable and moderate living space, and beautiful ecological space. This study collected data on marine environment remediation and ecological restoration projects implemented by the country from 2010 to 2015, and through the analysis-combination-induction model, initially established a project classification system suitable for the current status of marine environment remediation and ecological restoration work in China.

In the context of the “dual carbon” goal, a high proportion of renewable energy connected to the grid to replace traditional high-carbon units has become a general trend. Taking the high proportion of renewable energy power system as the research object, the medium and long term planning of the installed capacity of source, grid, load and storage of power system is carried out considering the two dimensions of investment and operation maintenance, and the optimization model of source, grid, load and storage of power system is established. A low-carbon dispatching model considering carbon emission and demand response of distribution network is also proposed. Firstly, considering the characteristics of distribution network receiving power from the main network, the carbon emission model of distribution network based on carbon emission flow theory is constructed, and the low-carbon index of distribution network is proposed. Secondly, the improved dynamic carbon emission factor of distribution network is proposed, which is used as a guide signal to provide reference for low-carbon electricity consumption of distribution network users. According to the characteristics of users in the distribution network, the industrial demand response model aiming at low dispatch cost and low carbon and the residential demand response model aiming at electricity consumption satisfaction and low carbon satisfaction are constructed respectively.

Good natural ventilation is one of the basic conditions for people to be able to work and live indoors. In this paper, wind velocity, wind velocity non-uniformity coefficient and air age are taken as the evaluation indexes of indoor ventilation condition. A simulation software Airpak is used to build room models with three window types (with the same ventilation area), namely, top-hung window, casement window and sliding window. The wind incidence angle was adjusted between 0°- 90°, and the indoor wind velocity and air age of the room were simulated when the casement window was opened at 90°, the sliding window was fully opened and the top-hung window was opened at 30°. The average wind velocity, wind velocity non-uniformity coefficient and air age of the room under each working condition were calculated and analyzed to evaluate the freshness and comfort of the indoor air, so as to provide guidance for the reasonable design of indoor layout.

The thermal reaction of SF6 with tungsten powder was investigated by thermogravimetry (TG) and differential scanning calorimetry (DSC), combined with the characterization of solid decomposition products of SF6 and tungsten by SEM, EDS, XPS and Raman. Based on above experiments, a two-stage decomposition process of SF6 with tungsten was proposed: the first stage is the surface vulcanization reaction W+SF6→S2, mainly taken place at 600 °C, with the activation energy valued at 152.8 kJ·mol-1, according to Avrami-Erofeev equation; the second stage is the endothermic fluorination reaction WS2+SF6 →WF6, mainly taken place at 750 °C,, with the activation energy valued at 126.0 kJ·mol-1 according to the Avrami-Erofeev equation.

With the development of society and the continuous improvement of market economy, the economic environment of enterprises has changed greatly, the competition between enterprises is becoming more and more fierce, and the survival of enterprises has also been greatly challenged. In this context, the performance evaluation of enterprises has attracted the attention of the whole society, especially the scholars and experts in the business community, and the theory and method of enterprise performance analysis have also been further deepened and developed. With the help of the principal component analysis (PCA) model and management accounting tools, this paper aims to correctly evaluate the performance of enterprises, find the factors that affect the performance of enterprises, and then put forward some suggestions, hoping to provide reference for the performance evaluation of enterprises, improve the core competitiveness of enterprises, and help enterprises develop and grow better under the new situation.

This article aims to study how to integrate the educational goal of cultivating talents through moral cultivation with the theoretical and practical teaching of the professional course. In order to realize a new teaching pattern of education, the study combined the professional course teaching with the ideological and political theory course teaching during the research process. Based on the practical teaching cases, this study followed the principle of combining qualitative and quantitative researches. The paper adopted several effective methods such as observation method, literature research method and case analysis method. It sums up the implementation approach of curriculum ideological and political construction strategy of “three integrations, two innovations and one connection”, so as to fulfill the fundamental task of establishing morality and cultivating talents.

Because ships burn inferior fuel, the emission of ship exhaust gas has a great impact on the environment. In order to effectively deal with the increasingly strict limit of sulfur content and SO2 emission of ship fuel by the International Maritime Organization. On the basis of analyzing the characteristics of SO2 gas soluble in seawater, this paper studies and compares the current industrial seawater desulphurization technology and other flue gas desulfurization technologies, puts forward the feasibility of the application of seawater desulphurization technology in the exhaust gas emission of marine diesel engine, and theoretically designs and calculates seawater desulphurization technology is pointed out.

In recent years, the rapid development of electric vehicle (EV) in China has played an important role in promoting the realization of carbon emission reduction and carbon neutrality in China. The EV charging standard directly affects the domestic and foreign sales of EVs, which is crucial to the sustainable development of the EV industry. This paper compares and analyzes the EV charging system standards in China and International Electrotechnical Commission (IEC), constructs a comprehensive evaluation index system for EV charging system standards, and builds a comprehensive evaluation model for EV charging system standards based on the fuzzy TOPSIS method. The comprehensive evaluation results of China and IEC EV charging system standards show that IEC standards as a whole are better than China 's, but some indicators in China are better than IEC standards. The future development of China's EV charging system standards should be aligned with IEC international standards to further promote the international standardization of China's charging scheme.

The smart water meter based on cloud computing is a new instrument that uses modern sensor technology, communication technology and modern microelectronics technology to measure water volume, transfer water data and settle transactions. The traditional water meter only has the function of flow collection and pointer mechanical display of water consumption. Compared with traditional water meter, smart water meter has great progress. With the development of wireless transmission technology and mobile communication network, remote water meter technology begins to develop rapidly.

In order to improve the teaching quality of graduate students, a quick method was designed to analyze the teaching evaluation comments in Chinese from students in the teaching evaluation system based on Baidu AI technology .So that it can help the teaching management department analyze the emotional inclination of students towards each course and grasp the trend and distribution of teaching quality accurately.The result of this article has shown that this method can analyze the students’ evaluation text correctly and provide decision-making reference for teaching management departments or teachers themselves.

For low-speed and large-thrust situations, the single-layer winding permanent magnet linear motor is inefficient because of its large distance, and the thrust fluctuation is large. In order to solve this problem, a finite element analysis model of cylindrical permanent magnet linear motor is established in a cylindrical permanent magnet linear motor, and the Ansoft software simulation is used to ensure the positioning force and thrust of the double-layer winding motor and single-layer winding motor under the same key parameters. The performance of double-layer winding motor and Single-layer winding motor at different frequencies is compared and analyzed. The simulation results show that the cylindrical linear motor with double-layer fractional-slot winding structure is more suitable for occasions with low speed and large thrust, and has higher operation efficiency.

Students' evaluation of teaching is a key link to realize teaching quality monitoring and promote teachers' teaching level. Based on the practice of student evaluation in our university, this paper constructs a multi-level student evaluation system, and develops an online student evaluation system by using JFinal+webix integration framework. The new Internet plus evaluation model is established to improve the efficiency of student evaluation and the enthusiasm of students to evaluate teaching. Meanwhile, based on the analysis of students' comments on teaching by Baidu AI platform, It provides data support for the improvement of learning level and the optimization of teaching evaluation.

When there are water rich-karst caves or large faults in front of the tunnel face, blind construction may easily cause safety accidents such as water inrush, mud outburst and collapse. Using advanced geological prediction methods to predict the spatial distribution of unfavorable geological bodies can greatly reduce construction risks. This paper introduces a new seismic reflection imaging system TSP-SK, and discusses the features, working mode and data processing methods of the prediction system, and verifies the reliability of TSP-SK through practical tunnel engineering prediction case. The result shows that TSP-SK can collect high signal-to-noise ratio seismic reflection data with little interference from clean first arrival when the water sealing effect of explosives in the borehole is good. Good reflection wave pickup effect can be obtained when the maximum gain of inverse Q filter and Q value are taken in the range of 15 to 30. The prediction results of TSP-SK are in good agreement with the actual excavation results, that is, the areas with low P-wave velocity indicate poor rock mass quality, and the area of low S-wave velocity is more likely to produce water from construction.

In order to meet the requirements of partial discharge (PD) detection of electrical equipment in substation station area, the ultra-high frequency (UHF) antenna with broadband, high gain and horizontal plane (H-plane) omnidirectional is studied and designed as a PD sensor. By analyzing the characteristic impedance and structural characteristics of the biconic antenna, it is determined to be an UHF omnidirectional wideband antenna for detecting PD. The influence of structural parameters such as half-cone angle and vertebral body height on the antenna performance is simulated. At last, a double cone antenna is made and its bandwidth, directional pattern, gain and equivalent height are tested.

Order to investigate the failure effect of textile reinforced concrete (TRC) plate under bending load, the corresponding finite element model is established. By comparing the numerical simulation results with the experimental results, the rationality and feasibility of the finite element model are verified, and then the crack extension of TRC and the ultimate strain of carbon textile are analyzed. The failure mode of the slab under bending load is obtained, and it is found that the carbon textile concrete slab has better reinforcement effect, which greatly improves the safety performance of concrete members.

Based on data collected in 20 A-level high-rise commercial concrete buildings in Hong Kong, the research successfully established a probability density function model, which is used to describe the carbon emissions profile of a commercial building. Results indicate that the superstructure of a commercial building, on average, had a footprint of 226.65 kg CO2/m2 and 10.6 kg CO2/m2 separately in the material use stage and transportation stages. It also evaluates the carbon emissions of various building elements and divides them into three levels according to the magnitude of their contribution. The results show that upper floor construction and external wall in Tier 1 contribute nearly 80% of emissions and should be of great concern. In addition to the probability density function model, a regression model was also successfully established in the study to predict carbon emissions. Research has shown that building layers and gross floor area can predict carbon emissions per unit area, and there is a positive relationship between the independent variable and the dependent variable. The regression model can help building designers determine design options to reduce carbon emissions in the early stages of design.

According to the "little boy" data from the United States, this paper simulates the primary γ-ray of the nuclear explosion and the secondary γ-ray produced by neutron, γ-ray and material interaction. At the same time, the linear attenuation coefficient spectra of 0.001mev to 100mev was calculated. The information was obtained from the point of the source projection of 500 meters to 1km. The results showed in the observation distance: The attenuation of the primary γ-ray energy was in line with the spectral γ-ray passing through the law of shielding the decay of the material. and it showed the phenomenon of the "hardening" of the energy spectrum. The fluence decreases an order of magnitude. The energy of the secondary γ-ray does not showed obvious attenuation laws, and the fluence decreases by about two orders of magnitude. It was worth noting that the average energy of the two kinds of γ-ray was around 2.100 MeV, and the fluence was in the same order of magnitude at 1km from the distance simulation.

Sarin (GB) and soman (GD) are severely toxic nerve agents that react slowly in water, resulting in long-term poisoning of the water and a serious threat to personnel. Some ions can catalyse GB and GD hydrolysis in water; the relevant research for GB is detailed, whereas that for GD is relatively less so. In this paper, GD hydrolysis catalysed by hypochlorite (ClO−) ions was studied via kinetic experiments. A fluorite-ion-specific electrode was used to monitor F− ions produced, allowing the rate constant and half-life of the GD hydrolysis to be calculated. The results showed that ClO− ions promote GD hydrolysis well; the higher the concentration of ClO−, the faster the GD was hydrolysed. In NaClO solution at pH 8.0 with 3.22×10–3 M ClO− ions, the half-life of GD hydrolysis was 82.5 s, about 875 times shorter than that in water at pH 8.0. The rate constant for catalysis of GD hydrolysis by ClO- ions ++(kc1o−)++ was 2.6 M−1 s−1, about one quarter the value of ++koh− ++but over 1500 times greater than kB and ++kPO4,++ with B representing N-2-hydroxyethylpiperazine-N’-2-ethanesulfonic acid present as a free base; this result indicated that ClO− ions catalyse GD hydrolysis well.

Peroxides like sodium percarbonate (SPC) and sodium percarbonate-acetylsalicylic acid (SPC-Aspirin) can be used to destroy chemical warfare agents (CWAs) such as HD, VX and GD due to the former's oxidation capacity and nucleophilicity. In this paper, experiments were performed to study factors affecting CWAs recovery from peroxides decontaminant water (decon water) and develop the method to recover residual CWAs from peroxides decon water before GC analysis. Results showed that extraction solvent and neutralization were important for high CWA recovery. DCM was more suitable than PE as extractant for most samples except SPC decon water containing HD. Sodium sulfite could well neutralized decontaminant reactivity in decon water. When suitable conditions of simultaneous neutralization and extraction were carried, CWAs recovery from SPC decon water were greater than 90% at a concentration range of 10 mg l-1 to 10000 mg l-1, the recovery of HD, VX and GD from SPC-Aspirin decon water was more than 90%, 80% and 95% respectively at a concentration range of 100 mg l-1 to 10000 mg l-1, while CWAs recovery were relatively lower from SPC-Aspirin decon water with CWAs concentration of 10 mg l-1 due to the degradation of CWAs during pretreatment processes.

Cyclo crosslinked polyphosphazenes (PPNs) were prepared by Hexachlorocyclotriphosphazene (HCCP) with unique P = n structure and active p-cl group and green compound phloretin. The synthesis pro cess of polyphosphazene nanospheres with Hexachlorocyclotriphosphazene as the main body and phloretin was discussed. The effects of pH value and solid-liquid ratio of solution on the adsorption of uranium by pol yphosphazene nanospheres were studied. The results show that polyphosphazene nanospheres are off white powder in appearance and spherical in microstructure. When the pH value of the solution is 4 and the solid-l iquid ratio is 0.5g ·L-1, the maximum adsorption rate of uranium is obtained.

Poly (cyclotriphosphazene-co-4,4 '- diaminodiphenylsulfone) (PZD) microspheres were synthesi zed by precipitation polymerization of Hexachlorocyclotriphosphazene (HCCP) and polyfunctional organic monomers. The products were characterized by FTIR, SEM-EDS, XPS and bet. The adsorption behavior of PZD microspheres for uranium (VI) in aqueous solution and the influence of adsorption behavior were disc ussed. The results show that the PZD microspheres have a certain adsorption capacity for uranium (VI) in a queous solution. When pH = 3.5, adsorption time is 6h, solid-liquid ratio is 2.0g • L-1 and initial concentration of uranium (VI) is 30mg • L-1, the adsorption rate of uranium reaches the maximum.

Aiming at the current imperfect hierarchical diagnosis and treatment system and the unreasonable spatial distribution of medical facilities. This article introduces 2SFCA model improved by the Gaussian distance decay function and multiple stage radius to evaluate the accessibility of medical facilities in Wuhan. The results indicate that: firstly, compared with the traditional 2SFCA model, the improved 2SFCA model is more sensitive to the identification of spatial accessibility, and the transition effect of the identification results is more obvious, which can accurately reflect the spatial distribution characteristics of the accessibility of medical facilities in Wuhan. Secondly, the distribution of medical facilities in Wuhan is obvious and the main factors that affect the accessibility value in different urban areas are quite different. Thirdly, the high value areas of medical facilities in the main urban area of Wuhan are mainly concentrated within the second ring line, the transition effect between the second and third ring lines is obvious, and the low value areas are mainly concentrated outside the third ring line. In the end, the main reasons for the low accessibility of the area outside the Third Ring Road are the low service quantity and low service ability of the community health service institutions and the high traffic resistance. The research results can provide a reference for the layout and planning of medical institutions in the main urban area of Wuhan.

With the rapid development of blockchain technology, more and more attention has shifted from the theoretical research of blockchain technology to the application of specific business of the company. However, there are few literatures on the quantitative research on the impact of blockchain technology on the company's market value after it is applied to the company's actual business. In this paper, 73 listed companies published blockchain application announcements from 2016 to 2019 are selected as the research objects, and the short-term event analysis method is used to quantitatively analyze the impact of the application about blockchain technology on the market performance of listed companies. The results show that: after the announcement of blockchain application in their own business, listed companies have a more significant abnormal income, which shows that the capital market has a significant positive response to the application of blockchain. Finally, this paper puts forward the theoretical and practical significance, limitations and future research.

With the rapid development of economy, the number of buses and bus fire increases. This paper takes bus as the research object and uses software FDS to explore the fire smoke spread under different fire power conditions. The results show that: with the increase in fire power, the smoke in the compartment rapidly accumulates, and the heating rate is also accelerated. The visibility decreases with the diffusion of smoke in the compartment. The CO concentration increases with time. The greater the fire power, the higher the temperature which will eventually stabilize. Only the concentration of smoke near the entrance will be slightly reduced. This is also conducive to the escape of people inside the car.

In order to provide an accurate theoretical basis for the underground gasification model test of coal, the similar materials ratio of underground gasification’s overburden rock was studied by orthogonal experiment according to the similarity theory. The results show: the fifth group material ratio meets the model test requirements, the mass ratio of sand, cement and gypsum is 6:1:1, and the compressive strength is 1.36MPa; the material strength is most sensitive to sand as compared to cement and gypsum; the compressive strength decreases as the aggregate–binder ratio increases. When the aggregate–binder ratio remains the same, the compressive strength decreases as the cement-gypsum ratio increases; the compressive strength-elastic modulus curve of the specimen increases linearly and conforms to the sandstone fitting curve in the coal-bearing strata; the failure mode of similar materials is mainly shear failure.

Fuyu oil layer of an oilfield is an ultra-low permeability oil layer. The remarkable characteristics of this oil layer are poor physical properties, low single well production, 2-4 layers of sand body longitudinally, large change frequency of plane upper layer and continuous characteristics. In order to realize effective oil layer development and ensure effective reservoir utilization. According to the poor physical properties of this oilfield, this paper analyzes the microscopic and macroscopic responsiveness of the reservoir, ensures effective permeability and thickness of permeable sand body, quantificationally depicts the plane distribution of permeable sand body, and effectively determines the distribution range of the reservoir according to the description of single sand body, thus providing a good technical means for subsequent scale production.

To evaluate the effects of dietary fiber from corn husks on hyperlipidemia, the hyperlipidemia model of mice was induced by trans-fatty acids diet,and the mice were randomly divided into the blank control group, the high fat control group(TFA group) and the low, middle and high dose group (2.5,5.0,10.0 G / kg) of dietary fiber from corn husks. Except the blank control group, the mice were fed with high fat diet. The body mass, serum total cholesterol, triglyceride, low density lipoprotein(LDL) and high density lipoprotein(HDL) were measured. The intake of trans-fatty acids resulted in a significant increase in the body weight, serum total cholesterol, triglyceride and LDL(P

The common analysis methods of structural building include the response spectrum, static nonlinear analysis (pushover) and dynamic nonlinear analysis method. Meanwhile, for the analysis of irregular structures, dynamic nonlinear analysis method could accurately simulate the seismic response of structure under rare earthquake. In this paper, the dynamic nonlinear analysis was carried out to evaluate the seismic performance of an office building with irregular in plan and in elevation. The simulation results show that the maximum inter story-drift angle can satisfy the requirement in the nation code. Few shear walls exceeded the concrete yield compressive stress and most of the shear walls remained in the elastic stage. Most frame columns were within the component acceptance criterion of IO. By the above analysis results, it can be judged that the seismic capacity of the building structure can reach the seismic performance objectives in the code.

In order to improve the solubility, emulsification and foamability of the Semen Euphorbiaee, and to improve the utilization of the Semen Euphorbiae, this experiment used glucose as a sugar source and modified the Semen Euphorbiae protein by wet glycosylation. Using solubility as a judgment index, a single factor test was conducted to optimize the conditions for the glycosylation reaction of the golden gold meal protein. The results showed that the solubility and other functional properties of the golden gold meal protein obtained by glycosylation under the conditions of pH 10.5, temperature 83.5 ° C, and meal protein / glucose mass ratio 1: 1.5 were improved.

Wireless sensor network has many sensor nodes with characteristics of limited cost, collecting data, good fault tolerance and storage. It has been used in environmental monitoring, health care, military and commercial. Coverage control is a significant issue that needs to be solved in wireless sensor networks. In order to solve the problem of overlapping coverage for environmental monitoring and improve coverage rate, an improved immune fuzzy genetic algorithm (IIFGA) based on cluster head selection is proposed. the mathematical model is systematically described. In the experiments, ant colony optimization (ACO) and simulated annealing (SA) are given to compare the performance of IIFGA. The experiments show the proposed coverage control algorithm has a higher convergence speed and improve the coverage rate.

Space formation aircraft communication system needs to meet strong anti-interference ability, low power consumption and high transmission rate performance. Ultra-wideband (UWB) has high data transfer rate, low device complexity, high interference resistance and confidentiality. Therefore, UWB technology is used in space formation aircraft communication system, which is direct sequence ultra-wideband (DS-UWB) space formation aircraft communication system. This paper, we put forward a multi-user detection (MUD) algorithm based on Gaussian Mixture Model (GMM) in DS-UWB communication system and its field-programmable gate array (FPGA) implementation. We adopt a way which based on MATLAB and FPGA platform, and results show that MUD algorithm based on GMM has better bit error rate (BER) performance compared to classical multi-user detection algorithm.

A novel bamboo-wood box beam was introduced in this paper, which consisted of laminated bamboo lumber flanges and OSB webs. Four-point bending tests were conducted on composite beams to investigate the effects of shear span ratio and stiffeners on failure mode and strength. The results showed that the composite beams with shear span ratio less than two failed in web shear failure, but for the others, the beams failed in twist and delamination of OSB in flanges. The load carrying capacity of beams decreased with the increase of shear span ratio. However, the mechanical performance of beams can be improved moderately by the presence of stiffeners, and theultimate bearing capacity and initial stiffness was increased by 16.5% and 13.1% respectively.

In this study, dewatered domestic sewage sludge of moisture content of 65.6% was used as a pore-forming agent to sinter Ceramics with kaolin clay, coal ash and sodium silicate at 1050-1100 oC for 20 min. The weight percentage of sludge of total dried solids was 60% with pore rate >45% and compressive >20 MPa. The Ceramics could be used as catalysts in heterogeneous Fenton-like system to treat phenol wastewater through modification by FeSO4 solution. After reaction with ceramics catalyst for 2.5 h, phenol removal of the wastewater could reach 99.87% from 100 mg/L to 0.13 mg/L and the COD removal is 85.75%. The performance of this catalyst was stable and had no significant in 30d repeat experiments.

In-cylinder flow characteristics play a significant role in the fuel–air mixing process of Spark-Ignition Direct-Injection (SIDI) engines. Typically, planar Particle Image Velocimetry (PIV) is used to measure a representative velocity field sectioning through the center plane of the engine cylinder. However, a single flow field offers very limited perspective regarding the Three-Dimensional nature of the flow fields. Since the in-cylinder flow is stochastically complex, large datasets of flow field measurements along multiple planes are needed to provide a complete panoramic understanding of the flow dynamics. In this study, a high-speed PIV is applied to measure the crank-angle resolved flow fields inside a single-cylinder four-valve optical SIDI engine. Five flow fields along different tumble planes are captured. These five planes include two orthogonal planes cutting through the spark plug tip, two parallel planes sectioning through middle point of the intake and exhaust valves, and one plane through the centers of two intake valves. In addition, numerical computations are carried out with Large-Eddy Simulation (LES) model in CONVERGE. With the guidance from multi-plane PIV measurements, a novel validation approach is proposed in this study. The quantitative analysis and comparison between LES simulations and PIV experiments are divided in terms of global and local comparison indices. The global comparison indices provide a quantitative single value to quickly check the overall similarity of velocity directions and magnitudes between PIV and LES results of a specific individual plane. The local comparison indices further evaluate the similarity between the flow fields of LES and PIV point by point to identify any dissimilar regions and vortex features, which are likely to indicate the complex flow structures at low-speed regions. In summary, not only can the combined data analysis approach provide a reliable way for LES model validations, it can also reveal the physical quantifications of the complex in-cylinder flow characteristics.

In this study the novel integrated anaerobic/anoxic/aerobic (A/A/O) and shaft aeration process system which could enhance the nutrient removal efficiency of wastewater with a low carbon nitrogen ratio (C/N) was investigated. Several dissolved oxygen (DO) ratios (1.0-2.0, 2.0-3.0, 3.0-4.0 mg/L) were applied in order to obtain more knowledge on the biological nitrogen and phosphorus removal performances. The experiment was carried out on a lab-scale Shaft-Anaerobic-Anoxic-Aerobic (S/A/A/O) wastewater treatment system. The average removal efficiencies of the total organic carbon, total nitrogen and phosphorus were 84.0%, 82.0% and 93.7%, respectively. The result showed that the proposed system was promising for the treatment of wastewater with a low C/N ratio because that in this system nitrification and denitrification happened simultaneously. Besides, the system had an automatic return system and its floor area was small, which made it energy-saving.

This paper investigated the influence of limiter functions widely utilized in MUSCL-type (Monotone Upstream-centred Schemes for Conservation Laws) upwind numerical schemes on the solution accuracy of shockwave-containing flows. An incident shock interacting with laminar boundary layer developed on a flat plate was numerically simulated with the in-house developed code. A mixed-order grid convergence study was performed to assess the spatial errors of different limiters in simulating the selected shockwave-containing flow on flat plate. The conclusions are that, limiter functions implemented in the current in-house code play the critical roles in accurately predicting shockwave-containing flows. The mixed-order error estimator based on grid convergence study was proved to be applicable to evaluate the spatial errors of shockwave-containing flows, where the shock could reduce the nominal second- or third-order accuracy to first-order. The mixed-order estimator is conservative in the sense that the actual error is less than the error estimated, in the examined case.

The existing building energy-saving reconstruction has a large area in our country. If the performance indexes such as the shading coefficient, visible light transmittance and hardness of the coating heat-insulating glass are in the condition of reaching the specification, and it can meet the needs of energy conservation and reform in building, it is a suitable technology for economic application.

A class of boundary value problem for fractional functional differential equation with delay C D σ ω ( t ) = f ( t , ω t ) , t ∈ [ 0 , ζ ] , ω ( 0 ) = 0 , ω ′ ( 0 ) = 0 , ω ″ ( ζ ) = 1 , $ \left\{ {\begin{array}{*{20}c} {^{C} D^{\sigma } \omega (t) = f(t,\omega _{t} ),t \in [0,\zeta ],} \\ {\omega (0) = 0,\,\omega ^{\prime}(0) = 0,\,\omega ^{\prime\prime}(\zeta ) = 1,} \\ \end{array} } \right. $ is studied, where 2 < σ ≤ 3 , c D σ $ 2 < \sigma \le 3,\,\,^{c} D^{\sigma } $ devote standard Caputo fractional derivative. In this article, three new criteria on existence and uniqueness of solution are obtained by Banach contraction mapping principle, Schauder fixed point theorem and nonlinear alternative theorem.

It is very effective to solve the multi variable optimization problem by using hierarchical genetic algorithm. This thesis analyzes both advantages and disadvantages of hierarchical genetic algorithm and puts forward an improved simulated annealing genetic algorithm. The new algorithm is applied to solve the multiple traveling salesman problem, which can improve the performance of the solution. First, it improves the design of chromosomes hierarchical structure in terms of redundant hierarchical algorithm, and it suggests a suffix design of chromosomes; Second, concerning to some premature problems of genetic algorithm, it proposes a self-identify crossover operator and mutation; Third, when it comes to the problem of weak ability of local search of genetic algorithm, it stretches the fitness by mixing genetic algorithm with simulated annealing algorithm. Forth, it emulates the problems of N traveling salesmen and M cities so as to verify its feasibility. The simulation and calculation shows that this improved algorithm can be quickly converged to a best global solution, which means the algorithm is encouraging in practical uses.

The stable slurry was prepared by ball-milling with a certain proportion of silica fume as silicon source,glucose as carbon source and metal niobium (Nb) as additives mixed with alcohol water. After the slurry was dried and pulverized, put the powder into a tubular furnace heated to 650℃ for 2h under nitrogen atmosphere to prepare precursor, the heating rate was 5℃/min. Treated the precursor under vacuum by carbothermal reduction method to prepare silicon carbide (SiC) powder. The effect of temperature and additive content on the morphology of synthesised silicon carbide and the impurity removal order on product purity were explored. After firing at 1300℃,1400℃,1500℃ for 2 h, the 3C-SiC powders are detected, and as the temperature increased, the crystallinity of the product become better. When the content of the additive is 1% of the quality of the silica fume, the particle size of the silicon carbide synthesized at the temperature of 1500℃ is even and the dispersion is better. As for the impurity removal order, removed SiO2 first, then removed C can effectively remove the impurities in the product.

The composition and complexity of oily wastewater contains many solid particles, free oil, emulsified oil and so on.It brought about a series of environmental pollution problems when oily wastewater was directly discharged into rivers, lakes and other water bodies. Therefore, researchers are committed to study how to deal with oily wastewater to deal with oily wastewater to apply it to meet the requirements of water injection.Inorganic porous ceramic membrane has excellent properties among many filtering methods. For example, high temperature and high pressure resistance, resistance to acid and alkali, low energy consumption, no pollution to the environment and has a good prospect in the field of oily wastewater treatment, which has attracted the attention of many scholars not only at home but also on abroad. This article describes the present situation of the research on the treatment of oily wastewater by ceramic membrane in recent years, and expounded the significance of the treatment of oily wastewater to people’s lives and makes an expectation for the development of inorganic porous ceramic membrane in the future.

The self-consistent scheme (Budiansky, 1965) is one of the analytical methods to predict the effective properties of heterogeneous material. However, it has been noticed that this scheme cannot take the micro-structural information into the estimation. The full scale numerical simulation considering elaborately the micro-morphological characteristics, under certain conditions, needs too much computational resources (memory and time). A numerical version of self-consistent scheme based on finite element analysis is proposed to overcome the above drawbacks by combining the characteristics of numerical simulation and self-consistent scheme. As a demonstration, such scheme is applied to estimate the effective mechanical properties of bi-continuous composite in which all the constituent phases are on the equal status. The prediction is in good agreement with the full scale numerical simulation while the requirement on computational resource is reduced dramatically.

This study optimizes aluminum nitride (AlN) ceramics, in order to enhance the thermal performance of light-emitting diode (LED) packages. AlN coatings are grown on copper/ aluminum substrates as a heat interface material, using an electrostatic spraying process. The effect of the deposition parameters on the coatings is determined. The thermal performance of AlN coated Cu/Al substrates is evaluated in terms of the heat dissipated and compared by measuring the LED case temperature. The structure and properties of the coating are also examined a scanning electron microscopy (SEM). In sum, the thermal performance of the LED is increased and good heat resistance characteristics are obtained. The results show that using AlN ceramic coating on a copper/aluminum substrate increases the thermal performance.

This paper mainly introduces the hardware design of a new type of ocean buoy for multi-scale marine dynamic process. The buoy system can collect a number of real-time marine environment data and then transmit all the data back to the landing site through wireless module. The authors mainly designed the hardware circuit of the buoy system, including data collection system, data communication system, data storage system. Due to the buoy system will complete the marine observation work continuously for at least a month, so we add the low power consumption function which can realize the intermittent work for the data collection system. This paper also introduces the electromagnetic induction coupling technology of underwater sensors, the sea surface communication network technology, etc. The system can also extends to the ecological regional anomaly monitoring and the early warning of disaster weather.

Numerical simulation is used to predict the behavior and response of carbon fiber reinforced plastic (CFRP). Sometimes zero thickness of interface layer is introduced into the numerical model to investigate the inter-layer behavior like delamination. To investigate the influence of critical volume-type defect like void, usually appeared in matrix rich region at the interface between layers, on mechanical properties of CFRP, numerical models with different interface thickness were created and tensile property and three-point bending simulation results were compared to experimental ones. It is found that accurate result is obtained with increasing of the interface thickness and up to 20% that of layer thickness is recommended to model the matrix rich region.