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Fault localization (FL) and automated program repair (APR) are two main tasks of automatic software debugging. Compared with traditional methods, deep learning-based approaches have been demonstrated to achieve better performance in FL and APR tasks. However, the existing deep learning-based FL methods ignore the deep semantic features or only consider simple code representations. And for APR tasks, existing template-based APR methods are weak in selecting the correct fix templates for more effective program repair, which are also not able to synthesize patches via the embedded end-to-end code modification knowledge obtained by training models on large-scale bug-fix code pairs. Moreover, in most of FL and APR methods, the model designs and training phases are performed separately, leading to ineffective sharing of updated parameters and extracted knowledge during the training process. This limitation hinders the further improvement in the performance of FL and APR tasks. To solve the above problems, we propose a novel approach called MTL-TRANSFER, which leverages a multi-task learning strategy to extract deep semantic features and transferred knowledge from different perspectives. First, we construct a large-scale open-source bug datasets and implement 11 multi-task learning models for bug detection and patch generation sub-tasks on 11 commonly used bug types, as well as one multi-classifier to learn the relevant semantics for the subsequent fix template selection task. Second, an MLP-based ranking model is leveraged to fuse spectrum-based, mutation-based and semantic-based features to generate a sorted list of suspicious statements. Third, we combine the patches generated by the neural patch generation sub-task from the multi-task learning strategy with the optimized fix template selecting order gained from the multi-classifier mentioned above. Finally, the more accurate FL results, the optimized fix template selecting order, and the expanded patch candidates are combined together to further enhance the overall performance of APR tasks. Our extensive experiments on widely-used benchmark Defects4J show that MTL-TRANSFER outperforms all baselines in FL and APR tasks, proving the effectiveness of our approach. Compared with our previously proposed FL method TRANSFER-FL (which is also the state-of-the-art statement-level FL method), MTL-TRANSFER increases the faults hit by 8/11/12 on Top-1/3/5 metrics (92/159/183 in total). And on APR tasks, the number of successfully repaired bugs of MTL-TRANSFER under the perfect localization setting reaches 75, which is 8 more than our previous APR method TRANSFER-PR. Furthermore, another experiment to simulate the actual repair scenarios shows that MTL-TRANSFER can successfully repair 15 and 9 more bugs (56 in total) compared with TBar and TRANSFER, which demonstrates the effectiveness of the combination of our optimized FL and APR components. [ABSTRACT FROM AUTHOR]

Flexible perovskite solar cells (PSCs) have received great attention due to their low weight, high power ratio, and potential applications in wearable electronic products. The efficiency and stability of flexible PSCs are directly affected by the carrier extraction and transport capabilities of electron transport layer. Herein, efficient flexible PSCs are prepared through incorporating 2,5‐Furandicarboxylic acid (FDCA) multifunctional intermediate layer between tin oxide (SnO2) and perovskite, which can effectively eliminate defects at the interfacial to increase the electron mobility of the SnO2 layer, modify the surface of SnO2 to shift the conduction band upward to improve interface charge extraction, passivate the buried interface of perovskite to induce larger perovskite crystal growth, and establish a bridge between SnO2 and perovskite to improve charge collection efficiency. As a result, the rigid PSCs with FDCA display a champion power conversion efficiency (PCE) of 24.53% with a high open circuit voltage (VOC) of 1.204 V. Furthermore, the flexible device with FDCA achieves a high PCE of 22.10%, and preserve 90% of its initial PCE after aging for 500 h at ambient condition without encapsulation, and maintain 81% of its original PCE after 10,000 bending cycles. [ABSTRACT FROM AUTHOR]

Functional passivation agents have been shown to effectively optimize the crystallization process and passivate defects on the surface and grain boundaries. People have conducted extensive research on the passivation mechanisms of various passivation agents to obtain more effective passivation agents. Researchers are gradually focusing on natural ingredients in the search for suitable passivation agents due to the wide variety, green color, and ease of production. As a result, the natural chlorophyll component chlorin e6 (CE‐6) is first combined with perovskite solar cells (PSCs) to improve their performance. Following the incorporation of CE‐6 into the perovskite layer, various functional groups of CE‐6 are used to effectively reduce traps on the perovskite surface, suppress charge recombination at the interface, improve carrier transfer rate and carrier extraction efficiency, and ultimately improve efficiency. The optimal device achieves a power conversion efficiency (PCE) of 21.14% and maintains its initial PCE of 84% after being stored in a room‐temperature air environment for 500 h. Furthermore, semitransparent PSC (ST‐PSC) is made with 13.33% PCE and 5.53% average visible light transmittance. The findings show that natural material CE‐6 performs well in the perovskite layer and confirms the promising prospects for optimizing ST‐PSC. [ABSTRACT FROM AUTHOR]

Patients on maintenance haemodialysis (MHD) face social isolation due to the far‐reaching effects of their disease and treatment. Based on the Transactional Model of Stress and Coping, we analysed the relationship between perceived stress and social isolation in patients, and the mediating role of internal health‐related locus of control (IHLC) from the perspective of co‐existence of perceived helplessness (HEL) and perceived self‐efficacy (SEL). We used structured questionnaires to investigate 332 cases of young and middle‐aged MHD patients in four tertiary hospitals in Guangdong, China. Polynomial regression and response surface analysis were conducted, along with tests of mediating effects on the data. The research was based on STROBE guidelines. The results showed that perceived stress is significantly and positively associated with social isolation. When the HEL and SEL of perceived stress were congruent, the joint effect of the two was in a positive curvilinear relationship to social isolation, when the two were incongruent, the risk of social isolation was lower for "low HEL‐high SEL" patients compared to the "high HEL‐low SEL" combination. The more congruent in HEL ‐SEL, the lower the risk of social isolation for the patients, with the IHLC playing a mediating role in this association. This study reveals that the coexistence of perceived stress's HEL and SEL affects social isolation through congruent and incongruent matching mechanism, providing additional explanations for the mechanism of occurrence of patients' social isolation. [ABSTRACT FROM AUTHOR]

The northern part of Zhangqiu district in Jinnan City has developed a thick sedimentary formation from the late Paleozoic to the Cenozoic. In this district, relatively well-developed fault structures and magmatic rocks provide good geothermal conditions. Abundant geothermal resources have been discovered in the study area, with three geothermal wells located near the fault zone. Therefore, establishing the genesis model of geothermal resources is significant for their future sustainable development and utilization. Based on hydrochemical and isotopic data of the study area, hydrochemical characteristics, water-rock interaction process, recharge source and formation age of geothermal water have been analyzed in this study. Besides, the elevation of the recharge area, thermal reservoir temperature, and depth of hot water circulation have also been calculated. Research findings show that geothermal water in the study area is composed of Cl·SO4-Na·Ca or SO4·Cl-Ca·Na, whose hydrochemical components mainly come from water-rock dissolution in the similar hydrogeochemical process. The source of water recharge is supplied by atmospheric precipitation, at an elevation from +563 m to +616 m. The 14C apparent age ranges from 5.55 ka to 29.71 ka. The geothermal water is mixed with modern water and ancient water. The chalcedony temperature scale shows that the temperature of geothermal reservoir is at 41.9-52.4 °, with the circulation depth of geothermal water at 622-1,565 m. The study area is a small-opened karst hot reservoir with deep circulation, during which geothermal water is heated up. Formation and enrichment of geothermal water are significantly controlled by fault structures. The geothermal reservoir is of stratified and banded type, belonging to geothermal resources at medium-low temperature. [ABSTRACT FROM AUTHOR]

An experiment was carried out to study the characteristics of swirling pneumatic conveying of grain particles in horizontal pipeline, which can provide a reference for the design and optimization of swirling pneumatic conveying system of bulk grain pipeline. The numerical simulation of swirling pneumatic conveying under the guidance of vane swirling generator was performed via CFD‐DEM coupling method. The axial velocity of grain particles was symmetrical along the radial direction, and the tangential velocity was symmetrical along the pipe axis. When the blade number of the swirling device was 6–9, the static pressure drop and standard deviation of the flow field were large, the instantaneous energy consumption of the system and the dispersion of particles were high, and the conveying effect was good. When the blade number was six, the spiral distance of the flow field in the pipe was longer with better quality of swirl flow. In accordance with the simulation results, the best effect of swirling conveying is achieved when the equivalent diameter of the grain particles is 4 mm, the multiphase flow conveying speed is 20 m/s, and the spiral blade number of the swirling flow generator with flow deflector is six. Practical application: In the practical application, the swirling flow generated by the swirling device can suppress the settlement of particles and the blockage of the pipeline in the straight pipe conveying, and avoid the high speed collision between particles and the pipe wall in the curved pipe conveying, slow down the impact, reduce the particle breakage and the wear of the pipe wall. The generation and maintenance of swirling flow play a key role in the long‐distance conveying of various chemical raw materials, grain, fertilizer and other granular materials. Swirling flow pneumatic conveying has the advantages of simple equipment structure, small occupation space, flexible pipeline layout, easy to automatic control, high production efficiency, recycling, environmental protection, and so on. It has become an important conveying mode in bulk material conveying. [ABSTRACT FROM AUTHOR]