Vectorizing line drawing is necessary for the digital workflows of 2D animation and engineering design. But it is challenging due to the ambiguity of topology, especially at junctions. Existing vectorization methods either suffer from low accuracy or cannot deal with high‐resolution images. To deal with a variety of challenging containing different kinds of complex junctions, we propose a two‐phase line drawing vectorization method that analyzes the global and local topology. In the first phase, we subdivide the lines into partial curves, and in the second phase, we reconstruct the topology at junctions. With the overall topology estimated in the two phases, we can trace and vectorize the curves. To qualitatively and quantitatively evaluate our method and compare it with the existing methods, we conduct extensive experiments on not only existing datasets but also our newly synthesized dataset which contains different types of complex and ambiguous junctions. Experimental statistics show that our method greatly outperforms existing methods in terms of computational speed and achieves visually better topology reconstruction accuracy.

Flexible magnetic materials with robust and controllable perpendicular magnetic anisotropy (PMA) are highly desirable for developing flexible high-performance spintronic devices. However, it is still challenge to fabricate PMA films on polymers directly. Here, we report a facile method for synthesizing single-crystal freestanding SrRuO3 membranes with controlled crystal structure and orientation using water-soluble Ca3-xSrxAl2O6 sacrificial layers. Through cooperative effect of crystal structure and orientation, flexible membranes reveal highly tunable magnetic anisotropy from in-plane to out-of-plane with a remarkable PMA energy of 7 × 106 erg·cm−3. First-principle calculations reveal that the underlying mechanism of PMA modulation is intimately correlated with structure-controlled Ru 4d-orbital occupation, as well as spin-orbital matrix element differences, dependent on the crystal orientation. In addition, even after 10,000 bending cycles, the PMA keeps stable, indicating a robust magnetism reliability in the prepared films. This work provides a feasible approach to prepare the flexible oxide films with strong and controllable PMA.

A neural-network-based cluster technique, the so-called self-organizing map (SOM), was performed to extract distinct sea surface temperature (SST) anomaly patterns during boreal winter. The SOM technique has advantages in nonlinear feature extraction compared to the commonly used empirical orthogonal function analysis and is widely used in meteorology. The eight distinguishable SOM patterns so identified represent three La Niña–like patterns, two near-normal patterns, and three El Niño–like patterns. These patterns show the varied amplitude and location of the SST anomalies associated with El Niño and La Niña, such as the central Pacific (CP) and eastern Pacific (EP) El Niño. The impact of each distinctive SOM pattern on winter-mean surface temperature and precipitation changes over North America was examined. Based on composite maps with observational data, each SOM pattern corresponds to a distinguishable spatial structure of temperature and precipitation anomaly over North America, which seems to result from differing wave train patterns, extending from the tropics to mid–high latitudes induced by longitudinally shifted tropical heating. The corresponding teleconnection as represented by the National Center for Atmospheric Research Community Atmospheric Model, version 4 (CAM4), was compared with the observational results. It was found that the 16-member ensemble average of the CAM4 experiments with prescribed SST can reproduce the observed atmospheric circulation responses to the different SST SOM patterns, which suggests that the circulation differences are largely SST driven rather than due to internal atmospheric variability.

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With China's adoption of principles-based international accounting standards and its convergence with International Accounting Standard 39 (IAS 39), Chinese companies have discretion under the original Accounting Standards for Enterprises 22 (CAS 22) as to how they account for the initial measurement, sale, and subsequent reclassification of financial assets. We use a Chinese company ('Company A') as a case study to illustrate how earnings are managed to exploit this discretion. We document that the company reclassifies its available for sale equity investments as long-term equity investments to decrease the volatility of the company's apparent profits. We also make some predictions regarding how the company will handle its financial assets under the new standard, which is the same as IFRS 9. Our research contributes to the continuous improvement of China's accounting standards and has implications for regulators of the capital market.

High-speed physical key distribution is diligently pursued for secure communication. In this paper, we propose and experimentally demonstrate a scheme of high-speed key distribution using mode-shift keying chaos synchronization between two multi-longitudinal-mode Fabry–Perot lasers commonly driven by a super-luminescent diode. Legitimate users dynamically select one of the longitudinal modes according to private control codes to achieve mode-shift keying chaos synchronization. The two remote chaotic light waveforms are quantized to generate two raw random bit streams, and then those bits corresponding to chaos synchronization are sifted as shared keys by comparing the control codes. In this method, the transition time, i.e., the chaos synchronization recovery time is determined by the rising time of the control codes rather than the laser transition response time, so the key distribution rate is improved greatly. Our experiment achieved a 0.75-Gbit/s key distribution rate with a bit error rate of 3.8 × 10−3 over 160-km fiber transmission with dispersion compensation. The entropy rate of the laser chaos is evaluated as 16 Gbit/s, which determines the ultimate final key rate together with the key generation ratio. It is therefore believed that the method pays a way for Gbit/s physical key distribution.

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