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31.
针对现有生成模型难以直接从复杂语义标签生成高分辨率图像的问题,提出了融合语义标签和噪声先验的生成对抗网络(SLNP-GAN)。首先,直接输入语义标签(包含形状、位置和类别等信息),使用全局生成器对其进行编码,并结合噪声先验来学习粗粒度的全局属性,初步合成低分辨率图像;然后,基于注意力机制,使用局部细化生成器来查询低分辨率图像子区域对应的高分辨率子标签,获取细粒度信息,从而生成纹理清晰的复杂图像;最后,采用改进的引入动量的Adam算法(AMM)算法来优化对抗训练。实验结果表明,与现有方法text2img相比,所提方法的像素精确度(PA)在COCO_Stuff和ADE20K数据集上分别提高了23.73%和11.09%;相较于Adam算法,AMM算法收敛速度提升了约一倍,且损失值波幅较小。可见,SLNP-GAN能高效地获取全局特征和局部纹理,生成细粒度、高质量的图像。  相似文献   
32.
The spin‐gapless semiconductors (SGSs) are a new class of zero‐gap materials which have fully spin polarized electrons and holes. They bridge the zero‐gap materials and the half‐metals. The band structures of the SGSs can have two types of energy dispersion: Dirac linear dispersion and parabolic dispersion. The Dirac‐type SGSs exhibit fully spin polarized Dirac cones, and offer a platform for massless and fully spin polarized spintronics as well as dissipationless edge states via the quantum anomalous Hall effect. With fascinating spin and charge states, they hold great potential for spintronics. There have been tremendous efforts worldwide to find suitable candidates for SGSs. In particular, there is an increasing interest in searching for Dirac type SGSs. In the past decade, a large number of Dirac or parabolic type SGSs have been predicted by density functional theory, and some parabolic SGSs have been experimentally demonstrated. The SGSs hold great potential for spintronics, electronics, and optoelectronics with high speed and low‐energy consumption. Here, both the Dirac and the parabolic types of SGSs in different material systems are reviewed and the concepts of the SGS, novel spin and charge states, and the potential applications of SGSs in next‐generation spintronic devices are outlined.  相似文献   
33.
A log statement is one of the key tactics for a developer to record and monitor important run-time behaviors of our system in a development phase and a maintenance phase. It composes of a message for stating log contents, and a log level (eg, debug or warn) to denote the severity of a message and controlling its visibility at run time. In spite of its usefulness, a developer does not tend to deeply consider which log level is appropriate in writing source code, which causes the system to be unmaintainable. To address this issue, this paper proposes an automatic approach to validating the appropriateness of the log level in consideration of the semantic and syntactic features and recommending a proper alternative log level. We first build the semantic feature vector to quantify the semantic similarity among application log messages using the word vector space, and the syntactic feature vector to capture the application context that surrounds the log statement. Based on the feature vectors and machine learning techniques, the log level is automatically validated, and an alternative log level is recommended if the log level is invalid. For the evaluation, we collected 22 open-source projects from three application domains, and obtained the 77% of precision and 75% of recall in validating the log levels. Also, our approach showed 6% higher accuracy than that of the developer group who has 7 to 8 years of work experience, and 72% of the developers accepted our recommendation.  相似文献   
34.
This paper reports an investigation on the structure-properties correlation of trivalent metal oxide (Al2O3)-doped V2O5 ceramics synthesized by the melt-quench technique. XRD patterns confirmed a single orthorhombic V2O5 phase formation with increasing strain on the doping of Al2O3 in place of V2O5 in the samples estimated by Williamson-Hall analysis. FTIR and Raman investigations revealed a structural change as [VO5] polyhedra converts into [VO4] polyhedra on the doping of Al2O3 into V2O5. The optical band gap was found in a wide semiconductor range as confirmed by UV–visible spectroscopy analysis. The thermal and conductivity behavior of the prepared samples were studied using thermal gravimetric analysis (TGA) and impedance analyzer, respectively. All the prepared ceramics exhibit good DC conductivity (0.22–0.36 Sm-1) at 400 ?C. These materials can be considered for intermediate temperature solid oxide fuel cell (IT-SOFC)/battery applications due to their good conductivity and good thermal stability.  相似文献   
35.
ABSTRACT

The hydrophobic polyether sulfone membranes were prepared by the sol-gel method to be applied in an air gap membrane distillation setup for desalination. The surface modifications were carried out using Trimethylsilyl chloride (TMSCl) and Methyltrimethoxysilane (MTMS) solutions. The membranes were characterized using Attenuated Total Reflection Infrared (ATR-IR) spectroscopy, Scanning Electron Microscopy (SEM), and Optical Contact Angle (OCA) methods. The effects of membrane preparation as well as operating conditions such as temperature difference, salt concentration, feed rotation speed, and cold-side temperature on membrane performance were investigated using central composite design method. It was found that feed temperature has the largest effect among the parameters on the permeation flux. The flow rate and salt rejection of the membrane in the optimum conditions were 4.47 Kg m?2 h?1 and 99.37%, respectively.  相似文献   
36.
Connexin43 (Cx43), the main gap junction and hemichannel forming protein in the urinary bladder, participates in the regulation of bladder motor and sensory functions and has been reported as an important modulator of day–night variations in functional bladder capacity. However, because Cx43 is expressed throughout the bladder, the actual role played by the detrusor and the urothelial Cx43 is still unknown. For this purpose, we generated urothelium-specific Cx43 knockout (uCx43KO) mice using Cre-LoxP system. We evaluated the day–night micturition pattern and the urothelial Cx43 hemichannel function of the uCx43KO mice by measuring luminal ATP release after bladder distention. In wild-type (WT) mice, distention-induced ATP release was elevated, and functional bladder capacity was decreased in the animals’ active phase (nighttime) when Cx43 expression was also high compared to levels measured in the sleep phase (daytime). These day–night differences in urothelial ATP release and functional bladder capacity were attenuated in uCx43KO mice that, in the active phase, displayed lower ATP release and higher functional bladder capacity than WT mice. These findings indicate that urothelial Cx43 mediated ATP signaling and coordination of urothelial activity are essential for proper perception and regulation of responses to bladder distension in the animals’ awake, active phase.  相似文献   
37.
Bismuth oxyhalides (BiOX (X = Cl, Br, I) are considered to be an important p-type semiconductors in the photocatalysis applications. In particular, tetragonal BiOBr is considered as a stable photocatalyst due to its resilient absorption in the visible region with an band gap energy of 2.8 eV. In the meantime, lanthanide ions (with 3+ oxidation state) implies as conversion catalyst gained huge impact and remain a serious topic in materials chemistry. Here we synthesized upconversion photocatalyst mainly consists of BiOBr with the Er 3+ and Tb 3+ ions along with low band gap g-C3N5 for the improved photocatalytic performances. The synthesized Er3+/Tb3+@BiOBr-g-C3N5 heterojunction was systematically characterized by XRD, and FT-IR for the confirmation of the composite and their morphology were analysed with FESEM and HR-TEM analysis which revealed that the sheets of g-C3N5 were decorated by Er3+/Tb3+ loaded BiOBr microspheres. The XPS analysis confirmed the suitable oxidation state of all the individual elements existing in the composite. As the UV-DRS analysis showed that the band gap of the Er3+/Tb3+ BiOBr-gC3N5 heterojunction was narrowed to 2.64 eV. To evaluate the photocatalytic efficiency of the synthesized g-C3N5, Er3+/Tb3+@BiOBr and Er3+/Tb3+@BiOBr-gC3N5 heterojunction under the simulated visible light irradiation source towards the aqueous sulfamethoxazole degradation. The Er3+/Tb3+@BiOBr-gC3N5 heterojunction shows maximum degradation efficiency of 94.2% after 60 min of visible light irradiation whereas the pure g-C3N5 provided about 43.8% and Er3+/Tb3+@BiOBr implies 55.2% degradation efficiency. The plausible degradation mechanism of pollutant removal was proposed.  相似文献   
38.
The balance between low carbon development and rapid economic growth is a ‘Gordian knot’ for most countries. This study aims to explore the practicable route of lowering carbon intensity with the expansion of the Information and Communication Technologies (ICT) industry in China. Using the provincial panel data from 2000 to 2017, the paper employs five indicators to empirically investigate the determinant mechanism of carbon intensity based on the refined Stochastic Impact by Regression on Population, Affluence, and Technology (STIRPAT) and spatial econometric models. The findings demonstrate that the ICT industry is the main force in adjusting carbon intensity. Despite constraint by the rebound effect, the net effect of the ICT industry shows a significant positive impact on lowering carbon intensity under the consideration of spatial dependence. Furthermore, compared with developed regions, the contribution of ICT on regional inequality of carbon intensity shows a higher share in developing regions. By applying the Oaxaca-Ransom counterfactual decomposition, the results reveal that there are substantial regional gaps between multi-comparable groups. The composite effect of informatization, industrialization, and urbanization accounts for the major share of the regional gap. Thus, policymakers should pay more attention to enhancing the ICT infrastructure in developing regions, boosting the ICT-related technology investment in specific sectors, coordinating regional cooperation, and balancing the migration of skilled workers.  相似文献   
39.
吕薇  姜根山  刘月超  张伟 《声学技术》2022,41(6):789-795
为了研究温度分布对于管阵列结构中的声透射特性的影响,以核电站的实际工况为背景,构建了不同的温度场以及周期性变化的非均匀温度场,利用有限元方法进行数值模拟。结果表明:(1)温度分布会改变管阵列声透射频谱的“禁带”宽度以及中心频率位置。在同一介质中,温度变化对频率较高位置的影响大于频率较低的位置。(2)在同样为10℃的温度差下,当水的平均声速为1 653 m·s-1、饱和水蒸气的平均声速为522.5 m·s-1时,介质为水时的禁带宽度及中心频率位置变化较大,即声速大的介质的频谱对于温度的变化更敏感。(3)当温度差在10℃以内,在周期性变化的非均匀温度场和与均匀温度场中管阵列声透射特性在第一中心频率23 996.1 Hz之前,两频谱差别很小,在第一禁带之后会出现明显区别。该研究成果对完善核电站应用的声学检测提供了理论基础。  相似文献   
40.
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