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In this study, the austenite transformation behaviour in a medium-Mn (MMn) steel is investigated during heat treatments that replicate those occurring in low-temperature hot stamping (LTHS), with the aim of better understanding this behaviour to optimise heat-treatment design. The austenitisation behaviour and critical phase transformation temperatures during the LTHS heating process and their dependence on heating conditions are investigated using dilatometry with a Gleeble 3800 thermal-mechanical simulator, covering heating rates of 1–25 °C s−1 and soaking temperatures of 630–900 °C. Both a higher heating rate and higher soaking temperature are found to be beneficial to shorten the time required for obtaining a given austenite fraction. The martensite start temperature (Ms) shows a rapid increase with increasing soaking temperatures when austenitisation is partial, and a slower increase after full austenitisation. Excellent ultimate tensile strength values of around 1750 MPa and total elongation values of around 9.3 % are obtained for the material after the LTHS heating process. A physically based model describing the austenitic transformation under these conditions has been adopted and calibrated. The model shows good agreement with austenitic transformation diagrams constructed from experimental data, and thus can function as a guide for selecting optimum heat-treatment parameters for LTHS.

Offset, gain and time mismatch errors exist in the channels of the time-interleaved analog-to-digital converter (TIADC), which severely affect the signal-to-noise and distortion ratio (SNDR), spurious-free dynamic range (SFDR) and effective number of bits (ENOB). Here, an error detection and correction method of TIADC based on genetic algorithm (GA) optimization is presented. The algorithm based on sine fitting is used for the first estimation and rough correction of the input signal, and GA is used for the second detection and fine correction of channel mismatch errors on the signal after frequency domain filtering. Experimental results show that the SNDR of the TIADC system is enhanced to 92.24 dB, the SFDR is enhanced to 102.05 dB, the ENOB is enhanced to 15.03 bits and the spectrum spurs are reduced. This method provides a new idea for error detection and correction of high-resolution TIADC systems with more than 16 bits.

China studies in Germany has undergone great changes since the 1960s. Influenced by burgeoning area studies in the United States, German scholarship shifted from traditional philological studies focused on translating and interpreting Chinese classics to practical studies of modern Chinese politics, economy, law, etc. Hence, there was also a shift in research methodologies to those of the social sciences. However, this shift, significant as it is, can never replace traditional Sinological studies aimed at Chinese history and classics. This paper uses Chinese history as an example to explore the development of German academic Sinology. It points out that research in traditional Sinology, as well as in modern China studies, no longer focuses on a particular discipline, but rather follows the trend toward interdisciplinary, comprehensive research. Hence we can expect that China studies will become increasingly decentralized and interactive in the future development of the field.

Improvement of the hot stamping process is important for reducing processing costs and improving the productivity and tensile properties of final components. One major approach to this has been to conduct all or part of the process at lower temperatures. The present paper reviews the state of the art of hot stamping techniques and their applications, considering the following aspects: (1) conventional hot stamping and its advanced developments; (2) warm stamping approaches in which complete austenitisation is not attained during heating; (3) hot stamping with a lower forming temperature, i.e., low-temperature hot stamping (LTHS); (4) advanced medium-Mn steels with lower austenitisation temperatures and their applicability in LTHS. Prospects for the further development of LTHS technology and the work required to achieve this are discussed.

The promotion of precise poverty alleviation in poverty-stricken areas will inevitably lead to changes in local folk customs. The economic development may bring about greater development of folk customs, and may also lead to qualitative changes in folk customs. This paper mainly introduced the impact of the precise poverty alleviation on the folk customs. Based on the analysis, it came up with pertinent control measures, to better combine the folk customs with precise poverty alleviation measures, to promote common development of economy and culture in poverty stricken areas.

From the perspectives of ecology, population, economy and society, this paper established an intensive land use system. From the aspects of land input, output and sustainable development, it built a new urbanization system. Besides, using the entropy weighting method, it measured the level of intensive land use and new urbanization of 31 provinces (cities or regions). Based on the coupling degree and coordinated development model, and in combination with GIS, it discussed the spatial differentiation pattern. It reached the following research results, (i) The new urbanization in the eastern region is ahead of the intensive land use, and they are relatively balanced in the western region; the new urbanization in the central and northeast regions lags behind the intensive land use; the intensive land use and the development of new urbanization in the eastern region are both stronger than that in central region, while the northeastern and western regions are weaker. (ii) The effect of sustainable land use in mainland China is remarkable, and the potential advantage of land output benefit in the eastern region is huge, the land input and sustainable development in the central region rank second, and the land output in the western region is the weakest. (iii) The development of new urbanization in mainland China is concentrated on economic and social urbanization; the eastern region has high economic urbanization benefits, while the western region is weak in both the ecological and population urbanization. (iv) There is significant unbalance of the spatial differentiation pattern in the intensive land use and new urbanization, showing a trend of high in east and low in west. (v) Most provinces (cities or regions) stay at a high level of antagonistic coupling, but there are “virtual high-level coupling” in regions such as Ningxia and Gansu; at present, the eastern, central and northeastern are moderately disordered, the western is highly disordered, and most provinces (cities or regions) are moderately disordered. Regions with high coordination level are concentrated in the eastern part of Guangdong and Jiangsu, Shandong, Shanghai, Henan, and Hebei; the coordination level of western regions such as Xinjiang, Gansu, Qinghai, Ningxia, Tibet, Guizhou and Yunnan badly needs to be upgraded.

Folk custom is specific embodiment of regional economy, society and culture, which has certain impact on targeted poverty alleviation work. Under the background, by analyzing logical relationship between folk custom and targeted poverty alleviation, and combining actual work experience, its impact on targeted poverty alleviation work is summarized. Analysis results show that folk custom has an active role in poverty alleviation through education, tourism and industry, and could obstruct poverty returning to certain degree. But its dross part brings stubborn conservatism, which hinders progress of regional thinking, reduces the effect of poverty alleviation, affects local people's behavior choice, and also obstructs popularization of poverty alleviation projects. Therefore, it needs conducting necessary guide and management of folk custom in targeted poverty alleviation work, changing existing habits and customs, developing advantages and avoiding disadvantages, which could improve the accuracy of poverty alleviation, and better achieve the goal of poverty alleviation.