Search

Zhejiang， as a crucial coastal province in China， deems the delineation of risk zones in its power system imperative for minimizing losses caused by typhoon disasters. Initially， the paper leverages historical data to comprehensively analyze meteorological features of typhoons in the Zhejiang coastal areas， focusing on aspects such as landing point distribution， path characteristics， temporal patterns， wind speed attributes， and precipitation features. Subsequently， an analysis of typhoon disaster characteristics in the Zhejiang power system is conducted. This entails examining the distribution of fault points in the transmission system， the relationship between the substation system and typhoon landing points， and the distribution of power outage percentages in the distribution system. Finally， utilizing historical data from both Zhejiang’s typhoon meteorology and power system， the paper creates a map outlining the risk zones for typhoon disasters. This includes a detailed delineation of high-risk areas for tower collapses， areas prone to wind deviations， and regions with high geological disaster risks. The analysis results aim to support risk assessment and response measures for typhoon disasters across various levels of the power grid.

The meteorological causes of wind deflection and tower collapse of a 500 kV transmission lines are analyzed. The wind speed distribution characteristics in the fault area of the line are obtained by using the observed wind speed of an automatic weather station and the three-dimensional wind field based on radar inversion. The results show that the maximum wind speed and the extreme wind speed observed by automatic weather stations around the two accidents are small. The three-dimensional wind field of radar inversion better indicates the fault's location and time. Compared with strong convective weather which can cause the wind deflection， the strong convective weather which can cause the tower collapse has a higher echo height and stronger updraft. The core height of its reflectivity factor drops more than 3.5 km within 6 minutes， causing greater ground damage， but its locality is strong and the influence range is small. The results show that the current design wind speed of the transmission line is safe under the strong convective weather that causes wind deflection， but adverse terrains that can accelerate the wind speed must be avoided. It is suggested to take “cascaded collapse prevention” as the main idea for the microburst which can cause the tower collapse. In addition， under the influence of strong convective weather， the gust coefficient calculated by the observed wind speed is significantly larger than the value in the relevant specifications.

Two-dimensional (2D) ferroelectric tunnel junctions (FTJs) have great potential in the design of non-volatile memory devices due to the tunneling electroresistance (TER) effect and the fact that it is not constrained by critical thickness. Incorporation of 2D ferroelectric materials in realistic FTJs inevitably involves the contacts to the traditional three-dimensional (3D) metals. However, how to design the FTJs by combining the 2D ferroelectric materials with the 3D metals still needs to be studied. In this work, we design a vertical 3D FTJ by adopting the 3D metal Au as the left and right electrodes and the 2D ferroelectric material In2Se3 together with h-BN as the central scattering region. By density functional theory combined with the non-equilibrium Green's function (NEGF) method, we demonstrate that the h-BN intercalation with a large bandgap plays the role of good "insulator," which breaks the symmetry of the left and right electrodes. As a result, we obtain the TER ratio of about 170%, and it can be further improved to about 1200% if two layers of In2Se3 (2L-In2Se3) are adopted as the tunneling barrier layer. Our results provide another way for the design and application of ferroelectric memory devices based on 2D ferroelectric materials. [ABSTRACT FROM AUTHOR]

Using the China Family Panel Studies, we identify the subjects studied by vocational college and university graduates, with the latter group further divided into ordinary and key universities. While the returns are around 8-10% to attending colleges and ordinary universities, there are higher returns of 12-16% per annum to attending the more prestigious key universities. The recent massive expansion of the higher education sector resulted in reduced returns to all HE types, except for graduates who studied subjects other than LEM (law, economics, and management) or STEM (sciences, technology, engineering and math/medicine) at key universities. We further account for selection on observables into subjects and tiers using the doubly robust Inverse Probability Weighted Regression Adjustment method (IPWRA) approach. While these results are tentative, they suggest that pooled OLS and random-effect models substantially underestimate the effect of attending universities that are more prestigious for graduates of both genders in LEM.

Two-dimensional (2D) ferroelectric materials exhibit significant potential for applications in nonvolatile memory and device miniaturization. In the device design stage, it is essential to consider the compatibility between 2D ferroelectric materials and three-dimensional (3D) metal. However, the interface between them introduces complex interactions that could impact the device's performance. In this work, based on the first-principles method, we simulate several 3D metal–2D ferroelectric material contact systems by utilizing different 3D metals in contact with the 2D ferroelectric monolayer CuInP2S6 (CIPS). By calculating the electronic structures of the systems, we find that the Cd(001)–CIPS configuration is the most stable structure, followed by the Ag(111)–CIPS and Au(111)–CIPS systems. Both the Cd(001)–CIPS and Ag(111)–CIPS systems undergo a transition from Schottky to Ohmic contact. Finally, we theoretically design a ferroelectric tunnel junction (FTJ) based on the Cd(001)–CIPS contact system, achieving a tunneling electroresistance ratio of 2.394 × 10 5 % and a remarkably low resistance–area product of 0.78 Ω · μ m2, which makes the proposed FTJ superior to the conventional 3D FTJ. This work provides some insights for the design of nonvolatile storage devices. [ABSTRACT FROM AUTHOR]

We investigate the impact of China’s outward foreign direct investment (OFDI) on the export sophistication of countries participating in the Belt and Road Initiative (BRI). Through an examination of data spanning from 2010 to 2015, our findings reveal that China’s OFDI significantly enhances export sophistication in host countries, with a more pronounced effect observed in relatively poor BRI nations. However, the positive correlation between China’s OFDI and export sophistication diminishes in host countries characterized by elevated productivity levels. Utilizing a structural equation model, we identify host country productivity as a crucial mediating factor. The indirect technology spillover effects of China’s OFDI, facilitated through increased productivity, account for approximately 39% of their overall impact on export sophistication. Furthermore, we delineate threshold effects of productivity for China’s OFDI, demonstrating substantial positive effects in host countries with a GDP per capita below the first threshold (approximately US$1,141) or within the range of the first and second thresholds (around US$7,115). Upon consideration of these thresholds, distinctions in the effects of China’s OFDI between BRI and non-BRI host countries diminish. Our analysis underscores that the favorable influence of China’s OFDI extends beyond the BRI, providing benefits to low and middle-income countries globally. [ABSTRACT FROM AUTHOR]

This study investigates the relationship between star power, artistic excellence, and the commercial success of Chinese movies from 2009 to 2018 based on a two‐path structural model. Artistic excellence was measured based on industry recognition; more specifically, the winners of seven major movie awards in the greater China region, which reflect the critical and popular evaluations of reviewers and consumers. The commercial success was measured by box office performance and the level of buzz among the audience. While the paths of artistic excellence and commercial movie success are essentially separable, as well as conceptually and empirically distinct, movie star power may influence both. Our findings indicate that star power had negative signal effects on critical and popular evaluation as well as industry recognition, but positive marketing effects on critical and popular buzz as well as box office performance. Indeed, star power has indirect positive effects that can outweigh its negative effects. Thus, star power is the key to success in these two seemingly unrelated paths in China. Moreover, these findings have several implications for international investors, producers, actors, and directors who are participating in the Chinese motion picture industry. [ABSTRACT FROM AUTHOR]

Using data from Chinese publicly listed companies (PLCs) over the 2010–2017 period, this paper examines the impact of cultural heterogeneity within the top management team (TMT) on the post-acquisition performance of cross-border acquisitions (CBAs). TMT cultural heterogeneity is measured as the cultural distance between the board chairperson and chief executive officer (CEO), based on the south-rice-north-wheat cultural dichotomy in traditional China in 1916. Overall, we find that TMT cultural heterogeneity can increase the likelihood of CBAs. However, it also has a significantly negative impact on both the market performance and profitability of privately-owned Chinese PLCs after the CBAs. To provide a comprehensive analysis, we also explore the moderating effects of state ownership and high-tech industries. The results reveal that TMT cultural heterogeneity can actually improve the market performance of CBAs conducted by state-owned PLCs, and it can enhance the profitability performance of CBAs within the high-tech industry. Our analysis highlights the significance of TMT cultural heterogeneity during the post-acquisition integration process following CBAs. [ABSTRACT FROM AUTHOR]

Ultrawide-bandgap semiconductors, possessing bandgaps distinctly larger than the 3.4 eV of GaN, have emerged as a promising class capable of achieving deep ultraviolet (UV) light detection. Based on first-principles calculations, we propose an unexplored two-dimensional (2D) InTeClO3 layered system with ultrawide bandgaps ranging from 4.34 eV of bulk to 4.54 eV of monolayer. Our calculations demonstrate that 2D InTeClO3 monolayer can be exfoliated from its bulk counterpart and maintain good thermal and dynamic stability at room temperature. The ultrawide bandgaps may be modulated by the small in-plane strains and layer thickness in a certain range. Furthermore, the 2D InTeClO3 monolayer shows promising electron transport behavior and strong optical absorption capacity in the deep UV range. A two-probe InTeClO3-based photodetection device has been constructed for evaluating the photocurrent. Remarkably, the effective photocurrent (5.7 A m−2 at photon energy of 4.2 eV) generation under polarized light has been observed in such a photodetector. Our results indicate that 2D InTeClO3 systems have strong photoresponse capacity in the deep UV region, accompanying the remarkable polarization sensitivity and high extinction ratio. These distinctive characteristics highlight the promising application prospects of InTeClO3 materials in the field of deep UV optoelectronics. [ABSTRACT FROM AUTHOR]

Low-dimensional ferroelectrics have a great deal of potential for use in electronic memory devices. However, intrinsic one-dimensional (1D) ferroelectricity is very rare. Using first-principles calculations, we present the discovery of an inborn 1D Ta4OTe9I4 ferroelectric (FE) nanowire. Its distinctive geometry can cause spontaneous electric polarization along the z-axis and allow it to maintain a certain temperature and strain. In addition to its sizable spontaneous polarization and appropriate Curie temperature, the 1D Ta4OTe9I4 nanowire exhibits an energy barrier comparable to those of other ferroelectrics. With polarization reversal, the energy gap can be modulated in the range of 0.38–1.33 eV, corresponding to an apparent peak shift phenomenon in the optical response. We use this nanowire as an exemplary material for building a FE tunnel junction composed of Hf0.5Ta3.5OTe9I4/Ta4OTe9I4/W0.5Ta3.5OTe9I4 with a giant tunneling electroresistance ratio at zero and low bias. Our calculations suggest that this 1D intrinsically FE material obtained from van der Waals crystals can be used in miniaturized and advanced high-density information storage. [ABSTRACT FROM AUTHOR]