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River water quality monitoring plays a crucial role in water environment protection and management. This paper aims to explore and innovatively propose an efficient and accurate water quality classification prediction model WOA-CNN-GRU composite model. By ingeniously integrating WOA, GRU, and CNN, this model conducts comprehensive predictive research on the complex and dynamic water quality environments of the Yellow River basins in China. Addressing limitations of traditional water quality prediction methods such as single-model approaches, inadequate data processing capabilities, and limited prediction accuracy, the WOA-CNN-GRU model constructed in this study integrates core technologies from different algorithms to achieve comprehensive analysis and efficient handling of water quality data.

In present work, Fields Activated Sintering Technology (FAST), has been applied to successfully sinter the high-entropy alloy (HEA) samples. Based on the analysis of the microstructure, relative density and microhardness of the sintered HEA samples, the influence of sintering temperature and pulsed magnetic field treatment (PMT) has been investigated. In terms of performance, HEA samples fabricated using PMT-powder sintering exhibit superior properties compared to UT-powders. Regarding elemental distribution, pre-treating the powders with a pulsed magnetic field can enhance the uniformity of the alloyed powder components. Furthermore, elevated sintering temperatures have been observed to substantially accelerate the densification process, thereby improving the relative density of the sintered samples.

Pulsed magnetic field treatment, as a novel, quick and environmentally friendly post-processing approach can directly modify the coated tools without causing damage. This study examined the wear performance of the TiAlSiN-coated cemented carbide block specimens treated by the pulsed magnetic fields in both dry friction and cutting fluid friction. The findings show that TiAlSiN coating block specimens subjected to pulsed magnetic fields exhibit better wear resistance in both friction conditions. The wear rate of the coating decreases by 21.49% in a dry friction environment, and the friction process becomes more stable while the wear width of the coating decreases by 4.60% in the cutting fluid friction environment. In addition, the nano-indentation tests show that the hardness and elastic modulus of the coating increases by 6.58% and 5.64%, and the coating binding force increases by 15.27% after the treatment.

In this study, we performed electric pulse treatment (EPT) on the cold-deformed 316L stainless steel. The effects of EPT on the temperature rise characteristics, tensile properties and microstructure of cold-deformed 316L SS were investigated. The results show that changes in current density have a significant effect on the surface temperature and tensile properties. Compared with the UT samples, at a current density of 44 A/mm2, the elongation after fracture reached a peak of 39.8% (the enhancement rate is 14.4%), while the ultimate tensile strength of all the EPTed samples shows no significant change. Interestingly, although the sample experienced an increase in temperature during the EPT process, the phase composition and grain structure remained unchanged significantly. This implies that the improvement in the ductility of the samples may be attributed to the reduction of micropores. The present research provides new light to the enhancement of ductility of cold-deformed 316L stainless steel.

Urban areas face significant environmental challenges, notably rainwater management and the urban heat island effect. As sustainable ecological infrastructures, Green roofs provide dual benefits in addressing these issues. The literature review thoroughly explores how effective green roofs are at boosting urban resilience by mitigating Urban Heat Island effects and enhancing stormwater control. Findings across various studies indicate that green roofs could significantly reduce surface and ambient temperatures, with some studies reporting surface temperature reductions of up to 30 °C. Additionally, green roofs contribute to stormwater management by retaining at lseast 51% of annual rainfall, thereby reducing runoff volume and peak flow rates. By synthesizing data from 28 case studies worldwide, this review highlights the substantial environmental benefits green roofs offer in urban settings. Our analysis suggests that broader implementation and further research into green roof technologies are essential for sustainable urban development. This paper calls for increased integration of green roofs into urban planning to leverage their environmental benefits, particularly in mitigating climate change impacts and enhancing urban ecological systems.

Watershed water quality monitoring is of great significance in water environment protection and management, and this paper proposes a water quality prediction model based on RBF neural network. Aiming at the parameter optimisation of RBF water quality prediction model, we propose to apply the sparrow search algorithm to optimise the parameters of the RBF model, aiming to improve the global search ability and convergence speed of the model. The characteristics of water quality parameters in the Shaanxi section of the Yellow River Basin were analysed using the model. Comparison with the RBF prediction algorithm is made, and the SSA-RBF prediction algorithm can significantly improve the prediction performance of the RBF model.

As the most advanced vegetable cultivation technology adopted all over the world, tray seedling is the key link of vegetables to increase crop yield and economic benefit. As the key to the whole production process, the precision of tray seedlings is directly related to the survival rate of seeds. Combining the small scale of the domestic vegetable tray seedling industry, low level of mechanization, and low profit of sowing equipment, a tray seedling precision seeder is proposed in this paper and ADAMS software is used to carry out dynamic analysis on the main stressed parts. The results showed possible problems in the design of this type of mechanism, and possible causes were analyzed, the structure of the precision planter was optimized based on the results, and the motion performance of the seeder was improved, which is of great significance for the realization of precision seeding in an automated assembly line.

The local government of China serves as a supervisor of vocational education. The vocational education governance is actually a dynamic game process involving local governments, vocational schools and enterprises. This study attempts to construct a multi-player evolutionary game and show the results that the external benefits of developing vocational education positively influence the probability of local governments choosing cooperative strategies. The choice of local government has a key impact on the strategic choice of vocational schools and enterprises. The vocational education policy would not only affect the calculation of benefit-cost, but also the strategic choice of local governments, vocational schools and enterprises. The research results can help local governments to formulate policies for vocational education development.

Encouraging rural households from deeply impoverished areas to participate in non-agricultural employment has been regarded as an effective way to alleviate rural poverty. China’s targeted poverty alleviation (TPA) project has made significant achievements, with its policy to encourage rural households to participate in non-agricultural employments playing an important TPA role. Taking a deeply impoverished county in Southwest China as an example, this paper used an endogenous switching regression (ESR) model under a counterfactual inference framework to evaluate the effects of nonagricultural employment on alleviating household poverty, with the simplified “Organization for Economic Co-operation and Development (OECD) equivalent scale” formula used to adjust the income to measure household welfare. It was found that non-agricultural employment had reduced participant poverty and greatly improved the welfare of the participating households. However, for the non-participants, the non-agricultural employment income would be lower than the agricultural income, and the transfer of the household labor force to non-agricultural employment would deepen household poverty. This paper concluded with a discussion of the policy options to consolidate the achievements of poverty alleviation in deeply impoverished areas.

The COVID-19 outbreak has a psychological impact on international students in China. Public psychological crisis prevention and intervention, and a timely economic and social restoration have become increasingly important. Focusing on international students in China, this paper summarizes different types of psychological issues and their causes after surveying the students’ mental health status and behavior changes. It proposes a systematic approach to address international students’ mental issues from three dimensions including government management, university education, and social support. It establishes the education model for international students’ mental health during the COVID-19 pandemic.

The reports on discrimination against the Chinese and Asian people has increased during the global COVID-19 pandemic. The study examined discrimination perceived by Chinese international students studying abroad during the COVID-19 pandemic, and constructed the theoretical conceptual model of perceived discrimination among Chinese international students based on the grounded theoretical analysis of the interview data. The study revealed the theoretical logic behind perceived discrimination among Chinese international students in the context of COVID-19 and offered some countermeasure suggestions.

As an important subject of the regional innovation system, the scientific research activities of universities are not only the power source of talent cultivation and knowledge innovation but also an important force to promote regional innovation development. This paper examines the influence relationship between knowledge spillover from universities in Sichuan province and Chongqing city and regional innovation capacity from the aspects of teaching and research personnel input, research and development personnel input in research input, monographs, academic papers, technology transfer contracts and transfer income in research output. The results show that the improvement of the innovation capacity in Sichuan province and Chongqing city depends on the increase of teaching and research personnel input and the number of scientific and technological topics in universities, while other indirect scientific research results do not contribute significantly to the regional innovation capacity; further mechanism analysis reveals that the knowledge spillover from universities mainly promotes the improvement of regional innovation capacity through human capital, physical capital, and scientific and technological innovation.

By analyzing the Z rime alternation phenomena in Changyuan Dialect of Henan Province, the present study argues that the phenomenon of one word having two different kinds of Z rime alternation forms in this dialect is due to it that the basic rime of the word preserves the Z rime alternation form that is formed before and after the sound change of the basic rime respectively. At the mean time, the development speed of Z rime alternation forms is slower than that of the basic rimes, so the Z rime alternation form preserves the glide of its corresponding basic rime of the early period and that’s exactly what leads to the differences between the glide of the present basic rime and that of the corresponding Z rime alternation form. Besides, the monophthongization phenomenon occurs between the main vowel and the [-u] ending in the compound final that is formed by sound combination during Z rime alternation process generally appears only in Jin language area of Northern Henan Province and doesn’t appear in Mandarin-speaking area of Henan Province.

Under the background of the new curriculum reform, the importance of English Teaching is becoming more and more prominent, and the teachers are always exploring the efficient English teaching mode. However, with the introduction of the new college entrance examination English reform and the double reduction policy, the disadvantages of the traditional high school English teaching mode of middle and high school English connection fault and other disadvantages have also emerged. Starting with the new college entrance examination reform background, this paper discusses the new scheme of English teaching in Liaoning Province.

China's government environmental protection-related departments attach great importance to the environmental pollution problems of petrochemical enterprises. The Environmental Protection Law as the core ecological regulation policy has been continuously improved to address the impact of macroenvironmental regulation on micro-individual petrochemical enterprises. The study subjects are 182 petrochemical companies from 2011-2021. The effect of different environmental regulations on the financial performance of petrochemical companies is studied empirically using a time-fixed effects model and a mediating effects model and using principal component analysis based on an agency cost perspective. The results show that environmental regulations significantly improve petrochemical firms' financial performance and suppress agency costs. Agency costs play a partial mediating role in the process of environmental regulations affecting financial performance.

Olivine-type lithium iron phosphate (LiFePO4) has become the most widely used cathode material for power batteries due to its good structural stability, stable voltage platform, low cost and high safety. The olivine-type iron phosphate material after delithiation has many lithium vacancies and strong cation binding ability, which is conducive to the large and rapid insertion of alkaline ions such as lithium, sodium and potassium. Therefore, the investigation of delithiation technology is of great significance. Electrochemical delithiation is a common method for preparing olivine-structured FePO4, which can maintain the structural stability and integrity of the material. In this work, the effect of voltage on the delithiation of LiFePO4 material was investigated by the electrochemical delithiation method in Na2SO4 as delithiation solution. The results show that 2.0 V is the best delithiation voltage, and the as-prepared FeO4 exhibits the highest specific capacity of 137.7 mAh g-1.

MnO2 is considered to be a prospective material for lithium-ion batteries anode. However, in practical applications, MnO2 has shortcomings such as low conductivity, large volume change and high charge transfer resistance, which seriously hinder its commercial application. In this work, MnO2 are preintercalated with various alkali cations (Na+, or NH4+) and coating with reduced graphene oxide through electrodeposition which designed for LIBs to improve its electrochemical behavior and understand the effect of cations and coating. It demonstrates that alkali cations can affect the growth morphology and electrochemical performance of MnO2, and graphene can improve electrical conductivity. Due to the advantages of its structure, MnO2&NH4+@rGO shows high capacity, rate performance (640 mAh g-1) and a long lifetime in lithium-ion batteries.

Further increasing the voltage is the most efficient means of acquisition to obtain lithium cobalt oxide with high specific capacity, but the irreversible phase transition of LiCoO2 at high voltage leads to poor electrochemical performance. In this paper, a 4.6V high voltage stable lithium cobalt oxide cathode material was achieved by simple high temperature solid-phase synthesis method doped with different contents of Mg elements. Under the condition of Mg content of 0.02, the specific capacity of discharge is 222.7 mAh/g at 0.5C, and the capacity retention rate is 93% after 50 cycles of 1C, showing good electrochemical performance.

Our country's higher education is based on “literacy” and “cultivating people” as the core. How to silently integrate ideological and political elements into the teaching process of engineering professional courses is a problem that requires thinking and long-term construction. In order to cultivate high-skilled and high-quality talents with both talents and virtues, it is urgent to build an ideological and political program suitable for engineering courses. On the basis of analyzing the national boundary attributes of engineering majors, this paper integrates ideological and political elements into engineering majors, and constructs an ideological and political teaching system for engineering majors. On the basis of knowledge imparting, ability training, and spiritual shaping in the design of professional courses, six ideological and political goals of courses are cultivated, and the ideological and political curriculum construction framework of professional courses is constructed by combining three teaching modules, and three ideological and political strategies are integrated into three courses. Taking the course of “Motor and Electrical Control Technology” as an example, this paper discusses the feasibility of the ideological and political construction plan for engineering majors.

Taking the key factors for the success of German “duale ausbildung” vocational education as the starting point, this paper introduces in detail five aspects: the leading role of the government, the main role of enterprises, the degree of social recognition, the team of dual qualified teachers, and the assessment and evaluation system. This paper analyzes the problems faced by vocational education in China, such as low social recognition, weak cooperation between schools and enterprises, inadequate talent training in schools to meet social needs, and insufficient attention from the government, and draws on the successful factors of dual vocational education in Germany to propose four inspirations for the reform of vocational education in China, including: improving laws and regulations, improving the security mechanism, improving the attractiveness of vocational education, strengthening the construction of “dual teachers” team Improve the social applicability of vocational education.

Through adding nitro-based fuel additive into diesel fuel,the influences of additive on engine performance, gaseous emission, particle number concentration and exhaust smoke were studied on a test bench. Meanwhile, the functioning mechanism and combustion characteristics were studied through constant volume combustion vessel. The system is composed of high pressure common rail fuel injection system, high pressure constant volume combustion vessel, high speed camera, data synchronization and acquisition system. The maximum diesel injection pressure is 160 MPa, and it can be heated to 1000 K under the back pressure of 3 MPa. According to the research results, adding fuel additive can decrease both exhaust smoke and exhaust temperature of engine for european steady state cycle(ESC). Moreover, The fuel additive improved the engine’s power slightly and expanded the economic fuel consumption working area. The minimum fuel consumption rate was reduced from 204.6g/kWh to 202.2g/kWh, and the highest fuel saving rate was about 2%. After adding MAZ, the mass of the recycled particles can be reduced by about 15%,and the average smoke intensity of most operating points showed a downward trend, with a maximum drop of 55%, the NOx weighted emissions of the whole cycle decreased by more than 2%. After adding nitro-based fuel additive, the ignition delay and flame lift-off length became longer in the combustion process, but the duration of combustion was shorter, which are in accordance with chemical reaction kinetics analysis.

With increasingly stringent emission and fuel consumption regulations, fuel additives have been proved to have a huge role in energy conservation and emission reduction, a new type of fuel additive based on nitroparaffin has received worldwide attention. An experimental study was conducted with the aim of developing an understanding of the fuel additive’s effect on a 1.5L naturally aspirated PFI gasoline engine’s power performance, fuel economy, emissions and cylinder cleanliness. The results show that when fueled with fuel additive, engine power increased at full load condition. The commonly used working condition’s average fuel consumption decreased by 4.5% at fuel consumption contour map. For pollutant emissions, unburned hydrocarbons (HC), smoke (filter smoke number, FSN) decreased significantly, slightly higher nitrogen oxides (NOx) compared with no fuel additive. Furthermore, the use of fuel additive has a positive effect on elimination of carbon deposit in the cylinder.

How can powerful countries be made to comply with international law? This question has been widely discussed by scholars. This paper expounds from three aspects: theory, famous case analysis and proposed solutions. First, how this problem came into being, secondly, its impact, and finally, how the country should deal with this problem.

Practical teaching is an indispensable and important part of teaching in higher vocational colleges. In view of the COVID-19 Era, teachers and students cannot carry out on-campus and offline teaching activities, which reduces the effect of practical teaching. In order to effectively carry out online practical teaching, the use of micro-video and simulation software through a variety of teaching platforms and online live broadcasts, “replacing reality with virtual reality”, increases the interaction between teachers and students, improves students’ participation, and achieves students. “The process of knowledge learning-knowledge internalization-knowledge solidification” solves the problem of insufficient hands-on ability in online teaching of practical courses.

With the international development of vocational education, cultivating international high-end technical and skilled talents who meet the requirements of modern industrial development and have international competitiveness has become an important responsibility of current vocational colleges. By introducing the German “duale Ausbildung ”education mode and learning from the IHK vocational qualification certification examination method, the two sets of teaching standards in the German“duale Ausbildung ”education, J Mechatronics framework teaching plan and Mechatronics vocational training rules, are integrated to establish a curriculum design that meets the requirements of the enterprise’s professional post ability, and “double tutors” or “multi tutors” cooperate with modular teaching, Reform and innovate the way of curriculum assessment and evaluation, and cultivate high-quality and highly skilled talents.

Through the online teaching survey of polytechnic, it is found that there are few mature high-quality online courses in polytechnic at this stage, teachers’ teaching ability and teaching methods cannot meet the teaching needs, and students’ learning initiative and enthusiasm are not high. In response to the above problems, it is proposed to use information technology to explore how to promote the reform of vocational education in the aspects of quality curriculum construction, teaching model innovation, assessment and evaluation methods, and new forms of integrated teaching materials.

Aiming at the problem of food risk prediction, this paper proposes a method based on clustering algorithm to predict product risk by raw material risk. Firstly, based on the provincial supply chain closed-loop hypothesis, this paper proposes the selection method of clustering indexes for products and their raw materials. Secondly, this paper uses the k-means clustering algorithm to cluster the products and the corresponding raw materials respectively, then based on the clustering Class results automatically determine the high-risk categories of the products and their raw materials. Finally, the analysis of the experimental data of the 8 categories of products and their raw materials shows that the ratio of the high-risk categories of products and the ratios of the corresponding high-risk categories of raw materials have a strong positive correlation. The experimental results prove the rationality of the raw material clustering index selection method proposed in this paper and the correctness of the method of predicting product risk based on the raw material risk based on the clustering algorithm.

The implementation of "the Belt and Road" initiative has further enhanced China’s economic openness and attracted more foreign direct investment (FDI). However, China is characterized by unbalanced economic development and distribution of resources in different regions. Therefore, analyzing the impact of FDI on economic openness of 18 provinces along "the Belt and Road" and developing the economies of these provinces more specifically have become an important issue. This paper uses factor analysis and DEA-Malmquist model to construct the economic openness of 18 provinces. FDI proxied by 5 measurements are selected to evaluate the impact of foreign direct investment on each province’s economic openness by using spatial econometric model. Empirical results find that FDI has a positive impact on the economic openness of the provinces along "the Belt and Road", and the surrounding provinces also have a significant role in promoting the economic openness of a province. But FDI has different impact on different regions with East Region exhibiting the most significant effect. FDI enhances economic openness mainly through registered capital of foreign-invested enterprises and total import and export of foreign-invested enterprises.

Vulnerability refers to the ability of a country or a region to resist internal and external natural factors such as ecological environment, economy, and society during its development. Germany is a country with low overall vulnerability and distinct regional differences, so research on its regional vulnerability can be a representative case for developing countries, as it provides a comprehensive assessment of regional vulnerability via scientific methodology and at the same time proposes rational solutions. The research collects quarterly data of 16 states of Germany from 2000 to 2015. This study describes a series of features of the data and establishes a comprehensive assessment of regional vulnerability including 33 indicators. Combined with the multi-criteria decision analysis method (MCDM), the analytic hierarchy process (AHP) method and the entropy method are applied to calculate the weights. A linear weighted sum method is applied to obtain the regional vulnerability index of Germany. Afterwards, by performing regression tests, this study empirically assess the influencing factors of the regional vulnerability of Germany. Moreover, this study adopts the neural network training model and forecasts the regional vulnerability of Germany of 2016 to 2020. This study identifies the main factors that influence the regional vulnerability of Germany, and proposes policy implications on the overall regulation to reduce the vulnerability of different regions in Germany accordingly.

The US aircraft carrier formation is a complex system-of -systems (SoS). Taking the logistics support organization system of the U.S. aircraft carrier as an example, the scientific management of logistics support SoS is discussed in this paper. Through the detailed discussion and analysis of the command relationship of the US aircraft carrier logistics support organization, as well as the discussion of the responsibility relationship of the U.S. aircraft carrier logistics support organization and its various agencies, the organization and command mode of US aircraft carrier logistics support are discussed. The management characteristics of US aircraft carrier logistics support organization SoS are summarized in detail.

With the continuous development of globalization, China has been devoted to promoting the degree of openness. The implementation of “the Belt and Road” initiative brings huge development prospects for China’s OFDI. Utilizing a panel data set consisting of a total of 51 countries along the “the Belt and Road” from 2007 to 2016, this paper establishes an empirical model and examines the influencing factors of the location choice on China’s OFDI in “the Belt and Road” countries. This paper collects comprehensive country-level data of 51 countries along “the Belt and Road” with Python. The number of investment enterprises in the host country published by the Open Directory of Record Results of Overseas Investment Enterprises (Institutions) is used as the explanatory variable. This paper conducts Poisson’s regression to study the influencing factors of location choice. According to the empirical results, bilateral trade agreements can help reduce the difficulties that China may face with in investing and facilitate China to access the host country for investment. In addition, Chinese enterprises may invest in countries where the degree of governance is moderate based on the negative impact on China’s investment in “the Belt and Road” countries. Also, China may invest in countries where the natural resources are poor considering the degree of governance even though natural resources have a positive effect on investment. Furthermore, the level of infrastructure construction in the host country has a positive effect on China’s direct investment in countries along “the Belt and Road”. Besides, good political environment can attract Chinese enterprises to invest in countries along “the Belt and Road”.

Lithium ion capacitors with liquid electrolyte are prone to leakage, combustion, explosion and other dangerous accidents. To solve these problems, the solid gel separator prepared by polyvinylidene fluoride - six fluoropropene (PVDF-HFP) is used in this work to improve the safety and stability of lithium ion supercapacitors. The PVDF-HFP based gel separator was used to replace the commercial separator and electrolyte in the lithium ion capacitor. The solid-state lithium ion supercapacitor was matched with porous carbon (PC) and hard carbon (HC). The maximum energy density of the device is 148.76 wh/kg, even at the power density of 33.6 kW/kg, which still retains 20.6 wh/kg. In addition, 83.3% capacity of solid-state lithium-ion supercapacitor is retained after 8000 times of charge and discharge. The requirements of high power energy density, high cycle stability and high safety are realized.

The NiCo2S4/C hybrid material was successfully prepared by a simple one-step hydrothermal method. Carbon composite increases the specific surface area of the material and provides more ion attachment points during the electrochemical process. Conducive to the ion transportation and transfer, the composition of carbon material greatly improves the conductivity of the hybrid material. Electric double-layer capacitor materials can accept transferred ions faster than pseudocapacitor materials, enable the hybrid materials better adapt to intensity current changes. Compared with a single carbon material or a pseudocapacitance material, it has a higher specific capacity. This discovery is of great significance to the research of pseudocapacitive materials and supercapacitors.

Security and stability control (SSC) system or special protection system (SPS) is an important means to ensure the safe operation of power grid. In view of the insufficiency that the current open-loop testing method cannot fully test the SSC system on-site, a remote real-time closed-loop test method is proposed. The solutions of key techniques such as information interaction, remote communication and signal conversion in remote test system are studied. Then the platform architecture and standard interface of the remote test system are designed. A remote test platform for SSC system is developed, and there application modes of the platform is deeply analysed. Finally, taking SSC system of Yunnan AC power outgoing grid as pilot application, experiment of two substations on-site is carried out. The results in practical project further prove the effectiveness of the method presented in this paper.

This paper discusses the influence of pH value, temperature and current density on the crystalline and amorphous structure of Ni-W alloy coatings during the electroplating process. The relationship between the corrosion resistance of Ni-W alloy coating and its crystal structure is discussed. In addition, the most common types of ternary systems and composite coatings for electrodeposited Ni-W alloy coatings are introduced. The effects of element types and contents on the hardness, wear resistance, corrosion resistance and thermal stability of Ni-W alloy coatings are analyzed. Finally, the current problems and development directions of Ni-W alloy coatings are proposed.

The fatigue test of wind turbine blade is an important means to verify the fatigue life of wind turbine blade. This paper analyses the problems existing in the fatigue test of wind turbine blade, focuses on the excitation mode, the relationship between excitation amplitude and vibration frequency and the vibration principle, and puts forward feasible solutions in practical operation.

In this paper, a photovoltaic grid connected electric vehicle charging station suitable for plateau application is developed by using two-way energy storage photovoltaic grid connected power generation technology; Introduce a medium-sized electric bus to carry out long-term operation test in Tibet; The detection experimental device and evaluation method suitable for electric vehicle power battery in plateau area are constructed; Carry out strategic research on the impact evaluation of the development of electric vehicles on the power grid side in the plateau weak current network area.

Minority settlements have good local landscape features and rich cultural heritage. However, due to complex geographical conditions and lagging economic development, there are many potential security threats in their human settlements. Based on the landscape ecological security pattern theory, aiming at eliminating the practical dilemma of frequent fires and difficult rescue in mountainous settlements in southwestern China, this paper proposes a planning idea to improve the settlement environment’s own disaster resilience and ecological endurance ability through the adjustment of landscape pattern. Taking the reconstruction planning and design of Xiaozhai Village in Longji of Guangxi province as an example, based on the geographical structure and resource characteristics of the village, a four-in-one landscape fire security pattern for mountain settlement is constructed, including building group, road evacuation system, natural fire protection network of water system and biological fire protection forest belt. The study provides a reference for the protection, renewal and re-planning of minority settlement.

An experimental loop apparatus of heat insulated waxy crude oil pipeline was established to study the wax deposition behaviors. The effects of flow rate and ambient temperature on the thickness and wax content of deposition layer were investigated. A kinetic calculation model for the thickness and wax content of deposition layer in heat insulated crude oil pipeline was established based on the principle of molecular diffusion, aging and shear energy. The results calculated by the model are in good agreement with the experimental values. The wax deposition thickness of a heat insulated crude oil pipeline in different seasons and operation time in Northeast China was predicted according to the theoretical model, which was anticipated that can provide a scientific basis for formulating the wax removal cycle of the pipeline. The predicted results showed that the thickness of the wax deposition layer increases first and then decreases along the pipeline.

With increasing degree of power electronics in power system, the interaction between controllers of different FACTS devices poses a greater threat to security and stability of the system. In this paper, a linearized state space model with SVC and STATCOM was established, and the negative interaction mechanism of FACTS device in transient process was analyzed and summarized considering control characteristics, operation mode and setting principle of PI controllers. A model predictive control (MPC) is proposed to replace traditional PI link to establish a coordination controller to overcome the difficulties of PI control parameter setting and global optimization.

SARS-CoV-2 is a new type of coronavirus, its source has not been accurately traced back. According to relevant medical studies, this noncellular morphological microorganism of about 60-140 nm in length may cause severe respiratory, cardiovascular and digestive system damage to infected patients. The disease caused by the virus is named as COVID-19 (Corona Virus Disease 2019) by WHO. For COVID-19, no matter it is an anonymous asymptomatic treatment by Chinese and Western medicine, there is currently no specific medicine. The Traditional Chinese Medicine (TCM) book named as “Basic Questions · Acupuncture Theory” points out that this kind of disease is a epidemic disease, easy to infect each other, and its symptoms are similar for all ages. Based on many years of traditional Chinese medicine nursing experience and authoritative literature, the author summarizes a set of traditional Chinese medicine characteristic nursing program for mild / ordinary type of SARS-CoV-2 virus infected patients, which can make the patient recover quickly. The main idea is to improve the patients’ resistance to the coronavirus by using traditional Chinese medicine characteristic nursing such as diet conditioning, scraping, massage, plaster, baduanjin exercise, moxibustion and Chinese medicine emotion nursing on the basis of TCM syndrome differentiation and classification. The TCM characteristic nursing program summarized in this paper has been applied to patients with mild / ordinary type of new coronavirus pneumonia, and has achieved good nursing results.

According to the survey, the concentration of pollutants in most buses exceeds the standard seriously, which not only reduces the comfort of passengers, but also harms the health of drivers and passengers. Therefore, it is very important to purify the air in the bus. However, there are many kinds of air pollutants in the bus, and the effect of single purification method is poor. Through the reasonable combination of activated carbon, photocatalyst and negative oxygen ions, the device can absorb and filter organic pollutants, bacteria and viruses in the air. Therefore, the device realizes the treatment of a variety of air pollutants in the bus, effectively improves the air quality in the bus, and also provides a healthy and comfortable travel environment for passengers.

Nb-Ti alloys are normally produced by vacuum arc remelting process. Due to inadequate processing parameters, freckles can be observed in macroetched ingots. In the present work, visual, chemical, metallographic, and X-ray are presented which establish the appearance, composition, microstructure differences between freckle regions and normal regions. It has been observed that in freckles parallel to the ingot axis, the Ti content is up to 53wt%, 7wt% higher than normal regions. It is also shown that a lot of precipitation phases appeared in freckle regions, because of the thermosolutal convection in the mushy zone. The Rayleigh number, which recommended as a criterion for freckle initiation, has been calculated that using a VAR melting software. Based on the experimental results and simulation results, it is concluded that freckles can be influenced by processing parameters, and freckles in Nb-Ti alloy can be eliminated by matching appropriate processing parameters.