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As the development and infrastructure of deepwater oil and gas resources, the performance of the deepwater offshore platform is directly related to personnel safety, equipment safety, normal production and drilling process. Therefore, hydrodynamic calculation[1] and flow response-based control and optimization are current hot research topics. Semi-submersible marine platforms are widely used in the industry due to their large deck area, strong wind and wave resistance, and excellent mining ability. However, their complex and diverse lines in the marine environment result in a series of dynamic responses due to wave loads, particularly in the rotating dynamic behavior, which cannot be efficiently controlled using traditional vibration control methods.Many research studies have focused on developing efficient control systems to suppress the dynamic behavior of semi-submersible marine platforms. For instance, active mass dampers (AMD) and tuning rotational inertia dampers (TRID) devices have been used to control the translation dynamic behavior of the platform. However, their performance in controlling the rotating dynamic behavior of the platform is unsatisfactory.To address this challenge, this paper proposes a new type of active control system called the Active Rotary Inertia Driver (ARID), which utilizes an active torque control system to suppress the rotating dynamic behavior of the semi-submersible marine platform. The ARID system is developed based on AMD and TRID devices and aims to enhance personnel and equipment safety, as well as the normal production and drilling process of the platform.Therefore, this study presents a comprehensive review of the research status on hydrodynamic calculation and flow response-based control and optimization of deepwater offshore platforms, particularly the semi-submersible marine platform. The proposed ARID system is expected to contribute to this research area by offering an efficient solution to the rotating dynamic behavior of the platform.

Perovskite quantum dots have been widely used in light-emitting diodes (LEDs) because of their adjustable color, high quantum yield and easy solution processing. Furthermore, matching energy levels of device plays a profound role in the resultant LEDs. In this study, a polymeric material, namely poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4’-(N-(pbutylphenyl))diphenylamine)] (TFB), is introduced between the quantum dot emission layer and the hole injection layer PEDOT:PSS, which not only prevents the fluorescence quenching caused by the direct contact between the perovskite layer and the hole injection layer, but also reduces hole injection barrier, both being beneficial to the device performance. The optimal thickness of TFB has been obtained by adjusting the rotational speed and precursor solution concentration during spin coating. The optimized quantum dots LED has a switching on voltage of about 2.2 V, a maximum brightness of 4300 cd/m2, a maximum external quantum efficiency of 0.15%, and a maximum current density of 0.54 cd/A.

Colloidal lead halide perovskites nanocrystals, also known as quantum dots, have been intensively studied as promising optoelectronic materials and have attracted widespread attention due to their unique optical versatility, high photoluminescence quantum yield and convenient synthesis. Among them, the potential of all-inorganic halide caesium lead perovskite (CsPbX3, X = Cl, Br, I) is particularly prominent. In this work, by adjusting the experimental parameters, including precursor preservation condition, reaction temperature and the isolation/purification process, CsPbBr3 quantum dots with uniform size, neat arrangement, narrow full width at half maxima and excellent luminescent properties have been successfully prepared, which lays a good foundation for its potential application in practical optoelectronic devices.

Over the last decade, the widely use of Building Information Modelling (BIM) has significantly improved the efficiency of architectural, engineering, and construction (AEC) industry in China. Many studies have been dedicated to how BIM could help in construction works. However, due to lack of BIM application in landscape filed, limited researches could be found on how many excessive works could be prevented by BIM and its ecological value in protecting local environment, especially for those hillside areas with relatively vulnerable ecosystem, which covers over two thirds of the land in China. This paper aims to set up a BIM-based landscape design workflow and examine its effectiveness in reducing construction waste produced in design process. One project case of hillside residential district planning design was carried out by applying the established BIM workflow, showing that earthworks were reduced significantly, and the final net cut/fill volume was controlled at 32.45m3 after project completion. Minimizing earthworks prevents the local topsoil and vegetation from been destroyed by unnecessary constructions. Utilizing BIM in landscape design enables the architects to pursue a more ecological and integrated design solution, paying more attention to the relationship between human beings and nature.

At present, COVID-19 is raging in many countries, which poses a great threat to people's life, health, social and economic development. Body temperature screening is very helpful for early detection of potential infected persons and blocking the spread of the epidemic. The paper mainly introduces the body temperature detection and data acquisition system, and designs a system with the function of non-contact temperature measurement and automatic data collection system. This system is suitable for the company or school where the flow of people is large and the temperature needs to be measured quickly, and upload information in real time.

Metal halide perovskites have received much attention for their application in light-emitting diodes (LEDs) and solar cells in the past several years. Among them, 2D and quasi-2D perovskite with organic long-chain cations introduced have drawn significant attention. However, while improving wet and thermal stability, as the grain size becomes smaller, more defects introduced at the grain boundary and surface, resulting in the increase of non-radiative recombination is becoming the main problem which should be faced by 2D/quasi-2D perovskite materials. Here, we report a new strategy employing ionic liquid named 1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide(EMB).By adding a small amount of ionic liquid to the precursor, the defect was effectively passivated and the photoluminescence intensity was increased by 11 times and the fluorescent lifetime was increased by about 1.5 times. The flatness of the prepared perovskite thin films has also been effectively improved.

A tree-like network heat sink with diverging–converging channel is designed, and effect of flow rate, channel diverging-converging angles on the flow and heat dissipation performance of the tree-like network heat sink is analysed and compared by numerical simulation. Results show that the diverging– converging angle of 2° can reduce the pressure drop by 14% when inlet mass flow rate is 0.00499kg/s. And the maximum temperature, the temperature difference between the maximum and minimum of the heat sink increases by 0.63K and 0.92K respectively. As the diverging-converging angle increases to 4°, however, it only reduces the pressure drop by 13% and can not bring more pressure drop due to formation of flow recirculation inside the tree-like network heat sink channel. Therefore, the diverging–converging fractal micro-channel heat sink with 2° has good heat dissipation performance with obvious lower pumping power.

In recent years, a novel Advanced High-Strength Steels called quenching and partitioning (Q&P) steel has been applied in the automotive industry because its good combination of strength and ductility. In this study, an experimental setup by adopting digital image correlation (DIC) method was firstly developed to establish the constitutive relationship of fusion zone in the spot welds produced by Q&P980. Stress-strain relationship extracted from the tensile bar within the fusion zone and compared the results to that of base metal. The fusion zone of Q&P980 found to have a higher tensile strength and similar elongation compared with base metal. A numerical model established to predict the failure mode of joints generated by Q&P980 after obtaining the constitutive relationship of fusion zone. The predicted failure mode was in good coherence with the experimental results under the lap-shear test conditions. The developed FE model was proven efficient in tensile strength and failure mode characterization of spot welded specimen. This study could provide solutions to maintain or even improve vehicle crashworthiness of lightweight vehicle structures.

Abstract An F2 chicken population was established from a crossbreeding between a Xinghua line and a White Recessive Rock line. A total of 502 F2 chickens in 17 full-sib families from six hatches was obtained, and phenotypic data of 488 individuals were available for analysis. A total of 46 SNP on GGA1 was initially selected based on the average physical distance using the dbSNP database of NCBI. After the polymorphism levels in all F0 individuals (26 individuals) and part of the F1 individuals (22 individuals) were verified, 30 informative SNP were potentially available to genotype all F2 individuals. The linkage map was constructed using Cri-Map. Interval mapping QTL analyses were carried out. QTL for body weight (BW) of 35 d and 42 d, 49 d and 70 d were identified on GGA1 at 351–353 cM and 360 cM, respectively. QTL for abdominal fat weight was on GGA1 at 205 cM, and for abdominal fat rate at 221 cM. Two novel QTL for fat thickness under skin and fat width were detected at 265 cM and 72 cM, respectively.

This paper establishes the model of sandstone, porosity and permeability on single well in allusion to 10 highly deviated and fractured wells in deep oil and gas reservoirs of Jidong Oilfield, which forms a numerical simulation method of highly deviated and fractured wells in deep oil and gas reservoirs of Jidong Oilfield. The numerical simulation results of highly deviated and fractured wells productivity in deep oil and gas reservoirs are given out under different layers (layer ES1, layer ES3, layer ED2,and layer ED3), different deviation angles(60° and 75°), different fracture parameters and producing pressure drops. Through the comparison with testing data getting from exploration wells, we know that the calculation results of numerical simulation are consistent with practical testing results.