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Higher education shoulders the task of cultivating high-level professionals with innovative spirit and practical ability. Undergraduate education plays a vital role as the beginning of higher education. However, the existing undergraduate teaching content is relatively outdated and the teaching mode is simple, making it difficult to stimulate students’ learning interest and improve their innovative practical ability. The scientific research project curriculum is rich in content and diverse in teaching forms, which can not only expand the teaching mode but also enrich and supplement professional knowledge. In this work, the teaching method of scientific research project curriculum is investigated in the investigated discipline - Material Science and Engineering. It is demonstrated that the introduction of scientific rlesearch project curriculum into undergraduate education or graduate education can help students improve their independent learning enthusiasm, professional practical skills, and innovative thinking abilities in the process of solving practical scientific research problems. Particularly, a project course about electrospun nanofibers is demonstrated to be a facile approach for achieving a comprehensive practice training for students. In a word scientific research project curriculum has proven to be a good teaching method for achieving “scientific research nurturing teaching”.

In this study, a pre-matching method was developed based on measured performance parameters and theoretical calculations of turbochargers. First, the turbocharger of a natural gas engine was subjected to a comprehensive performance experiment. According to the experimental results, the maximum efficiencies of the turbine and compressor are 70% and 75%, respectively, and the efficiency of the turbine drops sharply from 70% to 56.6% as the pressure ratio increases from 1.25 to 2.4. In this thesis, a specific turbocharger pre-matching software has been developed in conjunction with a database. Three turbines and three compressors were selected from the self-developed database for matching and comparative study using this method. The simulation results showed that the maximum efficiency of turbine #1, #2 and #3 is 71.3%, 72.2% and 72.7%, respectively, and the efficiency of these three turbines is concentrated between 65% and 72.5%. Obviously, the maximum efficiency of the turbine has increased by 1.3–2.7% and the overall efficiency has improved after the pre-matching. Therefore, this developed pre-matching method can reduce time cost, improve work efficiency and engine performance, and is important for the design and development of turbochargers.

In the present paper, the primary resonance of a fractional-order Willis aneurysm system with time-delay state feedback control is studied. Using the multiple scale method, the amplitude and phase equations are obtained. The first order approximate solution is derived and the influence of time delay on resonance is studied. The concept of equivalent damping related to time-delay feedback is proposed, and the reasonable selection of feedback gain and time delay is discussed from the point of view of vibration control. The frequency response and external excitation response curves of the system are given. In order to test the stability of the system, bifurcation analysis is carried out. The obtained results are very useful in the clinical diagnosis and treatment of cerebral aneurysms.

Combined with the structure of the solar greenhouse, this paper proposed a new type of solar greenhouse heating and ventilation system with the framework of the solar greenhouse as the carrier of heating and ventilation. The system’s return air mode, tuyere type, tuyere installation position and aperture ratio were determined by computational fluid dynamics (CFD). The results showed that: 1) When the inlet wind speed was 10m/s and the temperature was 37°C, using the upper return air method, the average temperature of the greenhouse crop area increases by 14.7°C, which was greater than 1.3°C of the lower return air and 2.3°C of the middle return air, the heating effect was the best. 2) Based on the nozzle and slot-type tuyere, five kinds of air outlets were designed. It was found that the use of the nozzle-type air outlet could promote the circulation effect of the airflow in the greenhouse and send more heat to the crop area. 3) When the aperture ratio was controlled at 1.5, the number of air outlets has little effect on the greenhouse heating effect.

Ocean acidification is a new problem for humans that rose recently. It has been drawing attention from people. It is getting more serious and important with the continuous carbon emission to the atmosphere. The threatens from ocean acidification are affecting multiple characters, especially organisms like marine animals and marine plants. Researches show the change in the pH will affect the lifespan and the reproduction process of marine organisms. Besides the impact on organisms, ocean acidification is also likely to impact the global climate. For places located around the tropical area, ocean acidification will bring more frequent storms and hurricanes. Focused on the problem, we want to seek solutions. However, currently, there are no direct ways to address the problem of ocean acidification. Some hypotheses have been made, such as managing the seaweed and the precipitation method, but these approaches are immature and currently inapplicable. The most practical method to slow down ocean acidification is to make agreements and regulations to directly control carbon emission. Future agreements should increase the collaboration internationally and apply the most suitable measures locally. This research aims to provide background knowledge for future studies about the ocean.

Architecture is the soul of city color. The planning focus of city color is city architecture, especially the planning control of the main wall color of street buildings. The design of architectural color should not only consider the surrounding environment of the building, the content of the building and the building materials, but also proceed from the aesthetic needs and conform to the principle of color engineering. On this basis, the plan proposes color design guidelines and relies on scientific and standardized “urban building color design guidelines” to achieve the purpose of maintaining the original appearance of history and creating a new era style. Besides the traditional buildings, the other “architectural color guidelines” should leave more room for manoeuvre and not restrict the creative thinking of architects.

Giardia duodenalis is an important zoonotic pathogen for both human and animal health. Although there have been reports on G. duodenalis infections in animals all over the world, information regarding the prevalence and genetic characteristics of G. duodenalis in sheep in Inner Mongolia, China, is limited. In this study, 209 sheep fecal specimens were collected in this autonomous region. We established that the prevalence of G. duodenalis was 64.11% (134/209), as determined using nested PCR detection and sequences analysis of the small subunit ribosomal RNA (SSU rRNA) gene. Based on the beta-giardin (bg) locus, the glutamate dehydrogenase (gdh) locus, and the triose phosphate isomerase (tpi) locus to study genetic characteristics, both assemblages A (2.99%, 4/134) and E (97.01%, 130/134) were found. Five novel nucleotide sequence of assemblage E were detected, two at the bg locus, two at the gdh locus, and one at the tpi locus. Multilocus genotyping yielded four assemblage E and two assemblage A multilocus genotypes (MLGs), including four novel assemblage E MLGs and one novel assemblage A MLG. Results of this study indicated that G. duodenalis was highly prevalent in sheep in Inner Mongolia. This study is the first to use the multilocus genotyping approach to identify G. duodenalis in sheep from this region.

In order to solve the problems of difficult assembly and adjustment and poor operation accessibility in the assembly process of multi-point pressure-type large-scale equipment on spacecraft, this paper presents a method of multi-point compact assembly of space mechanism driven by measurement. The method establishes the geometric constraint mathematical model of the equipment pressing mechanism, proposes the assembly coordinate system based on the mounting hole and the compensation method based on the rigid body transformation, and develops the relevant software according to the method. This method has been verified during the installation of the equipment and has achieved good results, which can be used as a reference for other digital assembly methods of aerospace equipment.

The management of satellites in orbit requires accurate and rapid processing to minimize the impact of failures. Especially for fault handling involving energy security, the real-time nature of the process plays a decisive role. This paper proposes a fast estimation method based on satellite telemetry data. Through the analysis of the shape of the telemetry curve, the geometric method, the correlation analysis of the telemetry data on the satellite, or the physical principles, the required parameters are quickly obtained to facilitate rapid emergency processing. This method is applied to satellite in-orbit management, which can greatly improve the real-time performance of fault processing, and has good engineering practical value.

In view of damages that are common in anti-seepage coiled joints used in the water-sealing of the concrete faced rockfill dam junction surface, the construction method that uses SK hand scraping polyurea and tire base fabric to quickly repair the broken coiled joint is proposed. By polishing the surface of the commonly-used Ethylene-Propylene-Diene Monomer (EPDM) board coiled material and using a special BU primer, good adhesion can be ensured between the SK hand scraping polyurea and the EPDM board. The EPDM boards were joined by docked joints and lapped joints, the boards were coated with SK hand scraping polyurea and adhered with tire base fabric, and the tensile and peel tests are carried out. The results show that SK hand scraping polyurea and EPDM board is well bonded. The method using for the connection of EPDM board joints has the advantages of simple construction, high speed, good quality and good anti-seepage effect, and it has been successfully applied to repair of damages of concrete faced joints on Pushi River pumped storage power station in Liaoning and the Nazixia hydropower station in Qinghai.

This paper describes the operation principle and the hardware composition of the wireless remote control cleaner by adopting solar panel power supply mode in detail. The experimental circuit is designed and on based on the designed experimental circuit the wireless remote control solar cleaner is made. The experimental results show that it is feasible that the combination of solar panels and wireless remote control cleaner.

Microstructural evolution, which is governed by temperature, strain and strain rate during hot forging, is a key factor influencing mechanical properties. Understanding the microstructural evolution of metals and alloys in hot forging has a great importance for the designers of metal forming processes. The principal objective of this paper is to provide an overview of the models for the prediction of microstructural evolution for metals and alloys during the hot forging process. In this review paper, the models are divided into four categories, including the phenomenological, physically-based, mesoscale and artificial-neural-network models, to introduce their developments, prediction capabilities and application scopes. Additionally, some limitations and objective suggestions for the further development of the modelling of microstructural evolution during hot forging are proposed.