Search

The value of the Buddhist cave lies not only in the Buddha statues but also in the surface painting. Hyperspectral imaging technology, as an emerging and effective method for component identification, offers a non-contact and non-destructive approach to the preservation and restoration of oil paintings. This study employed hyperspectral cameras to capture common pigments on the surfaces of Buddhist caves. Then, the results were processed and used as a database to identify the paintings. Additionally, a series of experiments were conducted to examine the impact of binder, substrate types, and pigment sizes on the reflectance spectrum of the paints. The Spectral Angle Matching (SAM) algorithm was then used to analyze the Yuanjue Cave and Qiqushan Stone Carvings of the Tang Dynasty in China. The findings revealed that the position of absorption peaks in the reflectance spectra is not significantly influenced by the substrate but is affected by the binder. Moreover, the absorption depth varies regularly with particle size. Furthermore, the spectral matching results demonstrate that components can be accurately identified even for similar colors. Based on the pigment distribution, the study also inferred specific details of ancient paintings, including the painting steps and hidden information in the manuscript layout. These findings hold significant implications for the restoration of representative surface paintings of the Tang Dynasty Buddhist cave, providing a reference for the selection of restoration materials and methods. [ABSTRACT FROM AUTHOR]

This study introduces an innovative method for identifying high-efficiency perovskite materials using an asymmetric convolution block (ACB). Our approach involves preprocessing extensive data on perovskite oxide materials and developing a precise predictive model. This system is designed to accurately predict key properties such as band gap and stability, thereby eliminating the reliance on traditional feature importance filtering. It exhibited outstanding performance, achieving an accuracy of 96.8% and a recall of 0.998 in classification tasks, and a coefficient of determination (R2) value of 0.993 with a mean squared error (MSE) of 0.004 in regression tasks. Notably, DyCoO3 and YVO3 were identified as promising candidates for photovoltaic applications due to their optimal band gaps. This efficient and precise method significantly advances the development of advanced materials for solar cells, providing a robust framework for rapid material screening. [ABSTRACT FROM AUTHOR]

In recent years, retailers can obtain consumers' demand information from rich market data, such as their browsing history and sales data. This gives retailers access to more demand information about consumers than manufacturers. Furthermore, many retailers have begun to share demand information with their upstream manufacturers who provide goods of a certain quality. Because an increasing number of consumers are concerned about product prices and product quality levels and are even willing to pay a higher price for high‐quality products, manufacturers consider two production modes to adapt to the market: the Q‐before‐IS mode or the Q‐after‐IS mode. To capture substantial consumer markets, retailers have also begun to provide their goods to compete with the manufacturers. Motivated by these practices, this study analyzes the retailer's information‐sharing strategy and the manufacturer's production mode selection under price and quality competition. We find that under the Q‐before‐IS mode, the retailer has no incentive to voluntarily share information with the manufacturer. However, under the Q‐after‐IS mode, the retailer would share two products' information with the manufacturer when the quality investment cost factor is relatively low. Our findings confirm that the retailer is induced to share information because the retailer and manufacturer participate in the quality and price competition after observing the demand. Moreover, the manufacturer prefers the Q‐after‐IS (Q‐before‐IS) mode under the equilibrium information‐sharing strategy when the demand fluctuation is large (otherwise). This indicates that the retailer's information‐sharing strategy plays a key role in the manufacturer's preferred production mode. [ABSTRACT FROM AUTHOR]

We consider a two‐stage dynamic pricing problem for a seller who employs online group purchasing with strategic customers. Customers who arrive in Periods 1 and 2 can decide whether to purchase the product in the current period, delay their purchases to the next period (for those customers in Period 1), or leave the market. The network externality, a typical characteristic of group buying, is captured in our model. That is, more customers who purchase the product would positively or negatively affect the demand. We investigate the impacts of positive/negative externality on the seller's prices, demands, and profits, respectively. By comparing positive and negative externality cases, we find that customers who purchase the product in Period 2 can enjoy a lower price than in Period 1 for negative externality. Interestingly, however, the price in Period 1 might be higher or lower than in Period 2 for positive externality, even if the corresponding demand is lower. Compared to no externality, our result shows that the seller should reduce the price in Period 1 but increase it in Period 2 because this helps increase the total demand and profit in the presence of a positive externality. Nevertheless, when there exists a negative externality, we confirm that the prices in two periods might both decrease for a lower externality, which leads to lower total demand and profit for the seller. Since the seller can decide whether to disclose their reviews or product historical sales to customers, this result can provide practical implications for sellers who adopt a group purchasing strategy. [ABSTRACT FROM AUTHOR]

The series-winding permanent-magnet synchronous motor (SW-PMSM) has the merits of high output power and excellent control performance, as does the open-winding permanent-magnet synchronous motor (OW-PMSM). Meanwhile, it can greatly reduce the number of power devices. However, due to the existence of the zero-sequence path, zero-sequence current occurs, which can cause additional losses and torque ripples. Thus, this paper proposes a novel direct torque-control strategy for the SW-PMSM with zero-sequence current suppression capability (ZSCS-DTC). First, the series-winding topology (SWT) and the voltage vector distribution in the SW-PMSM drives are analyzed. Secondly, the basic DTC (B-DTC) scheme for the SW-PMSM is investigated, and the defects of zero-sequence current open-loop control in the B-DTC scheme are revealed. Thirdly, a new voltage vector synthesis scheme is proposed for suppression of zero-sequence current while ensuring bus voltage utilization. A switching table is reconstructed with the newly synthesized voltage vectors. On this basis, a ZSCS-DTC scheme for the SW-PMSM is proposed based on zero-sequence current closed-loop control so that electromagnetic torque, stator flux linkage and zero-sequence current can be controlled simultaneously. Finally, the effectiveness of the proposed ZSCS-DTC scheme for the SW-PMSM drives is verified. [ABSTRACT FROM AUTHOR]

In practice, manufacturers sell products through online intermediaries (e.g., JD) that sell them to customers (reselling) or direct access to customers via intermediaries by paying a proportional fee (agency selling). Additionally, manufacturers can simultaneously employ reselling and agency selling, which we call hybrid selling. Motivated by practical examples in which these intermediaries possess superior demand information and choose whether to share it with their manufacturers, we develop a game-theoretic model to study the interplay between an intermediary's information-sharing and a manufacturer's selling format selection. When the information-sharing strategy is established before the selling format decision, it is always detrimental for the manufacturer to adopt the agency selling model. Specifically, the manufacturer should adopt the reselling (hybrid selling) model if the proportional fee is relatively large (small). Moreover, the intermediary should voluntarily share the information with the manufacturer if the fee is intermediate. When the information-sharing strategy is established after the selling format decision, the intermediary should not (should) disclose information, as the fee is relatively small (large) under the hybrid selling format. Additionally, the manufacturer could employ the agency selling (hybrid selling) model if the fee is sufficiently small and the competition intensity is relatively large (small). [ABSTRACT FROM AUTHOR]