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排序方式: 共有269条查询结果,搜索用时 78 毫秒
1.
Yichuan Liu Hui-Qi Qu Xiao Chang Lifeng Tian Jingchun Qu Joseph Glessner Patrick M. A. Sleiman Hakon Hakonarson 《International journal of molecular sciences》2021,22(7)
RNA-seq has been a powerful method to detect the differentially expressed genes/long non-coding RNAs (lncRNAs) in schizophrenia (SCZ) patients; however, due to overfitting problems differentially expressed targets (DETs) cannot be used properly as biomarkers. This study used machine learning to reduce gene/non-coding RNA features. Dorsolateral prefrontal cortex (dlpfc) RNA-seq data from 254 individuals was obtained from the CommonMind consortium. The average predictive accuracy for SCZ patients was 67% based on coding genes, and 96% based on long non-coding RNAs (lncRNAs). Machine learning is a powerful algorithm to reduce functional biomarkers in SCZ patients. The lncRNAs capture the characteristics of SCZ tissue more accurately than mRNA as the former regulate every level of gene expression, not limited to mRNA levels. 相似文献
2.
底吹钢包两相区两段模型 总被引:1,自引:0,他引:1
在考虑雷诺应力的基础上,建立了底吹钢包中气液两相区流体流动的两段模型。这一模型可用于计算近喷嘴处和浮羽流区各截面处两相流的平均速度、速度分布、流股直径和平均含气率等.数值计算表明:理论含气率与实验值符合很好.计算还表明:平均含气率和平均速度随高度的增大而减小,但流股直径随高度的增大而增大.另一方面,平均速度随初始供气量的增大而增大,而抽引比则随供气量增大而减小.通过两段模型可很好地描述喷嘴处气液流的行为. 相似文献
3.
Contextual Resource Negotiation-Based Task Allocation and Load Balancing in Complex Software Systems 总被引:1,自引:0,他引:1
Yichuan Jiang Jiuchuan Jiang 《Parallel and Distributed Systems, IEEE Transactions on》2009,20(5):641-653
In the complex software systems, software agents always need to negotiate with other agents within their physical and social contexts when they execute tasks. Obviously, the capacity of a software agent to execute tasks is determined by not only itself but also its contextual agents; thus, the number of tasks allocated on an agent should be directly proportional to its self-owned resources as well as its contextual agents' resources. This paper presents a novel task allocation model based on the contextual resource negotiation. In the presented task allocation model, while a task comes to the software system, it is first assigned to a principal agent that has high contextual enrichment factor for the required resources; then, the principal agent will negotiate with its contextual agents to execute the assigned task. However, while multiple tasks come to the software system, it is necessary to make load balancing to avoid overconvergence of tasks at certain agents that are rich of contextual resources. Thus, this paper also presents a novel load balancing method: if there are overlarge number of tasks queued for a certain agent, the capacities of both the agent itself and its contextual agents to accept new tasks will be reduced. Therefore, in this paper, the task allocation and load balancing are implemented according to the contextual resource distribution of agents, which can be well suited for the characteristics of complex software systems; and the presented model can reduce more communication costs between allocated agents than the previous methods based on self-owned resource distribution of agents. 相似文献
4.
Chuanming Tian Bin Li Yichuan Rui Hao Xiong Yu Zhao Xuefei Han Xinliang Zhou Yu Qiu Wei An Kerui Li Chengyi Hou Yaogang Li Hongzhi Wang Qinghong Zhang 《Advanced functional materials》2023,33(41):2302270
Despite the outstanding power conversion efficiency (PCE) of perovskite solar cells (PSCs) achieved over the years, unsatisfactory stability and lead toxicity remain obstacles that limit their competitiveness and large-scale practical deployment. In this study, in situ polymerizing internal encapsulation (IPIE) is developed as a holistic approach to overcome these challenges. The uniform polymer internal package layer constructed by thermally triggered cross-linkable monomers not only solidifies the ionic perovskite crystalline by strong electron-withdrawing/donating chemical sites, but also acts as a water penetration and ion migration barrier to prolong shelf life under harsh environments. The optimized MAPbI3 and FAPbI3 devices with IPIE treatment yield impressive efficiencies of 22.29% and 24.12%, respectively, accompanied by remarkably enhanced environmental and mechanical stabilities. In addition, toxic water-soluble lead leakage is minimized by the synergetic effect of the physical encapsulation wall and chemical chelation conferred by the IPIE. Hence, this strategy provides a feasible route for preparing efficient, stable, and eco-friendly PSCs. 相似文献
5.
Yichuan Chen Wencai Zhou Xiaoqing Chen Xiaobo Zhang Hongli Gao Nabonswende Aida Nadege Ouedraogo Zilong Zheng Chang Bao Han Yongzhe Zhang Hui Yan 《Advanced functional materials》2022,32(1):2108417
As one of the most promising photovoltaic materials, the efficiency of inorganic–organic hybrid halide perovskite solar cells (PSCs) has reached 25.5% in 2020. However, the stability and hysteresis remain primary challenges before it can become a commercial photovoltaic technology. Therefore, those issues have drawn significant attention for photovoltaic applications. In this work, a study of the PSCs hysteresis improvement is presented based on a combination of first-principles simulations, scanning electron microscopy images, and time-dependent photocurrent measurements. It indicates the hysteresis led by the ion migration and accumulation is mainly localized at the two interfaces: one is between electron transport layer and active layer, and the other is between active layer and hole transport layer. Considering the massive defects at the grain boundaries (GBs), they lower the potential barriers significantly. The defect density at GBs is therefore reduced via the in situ passivation of PbI2 crystals. The hysteresis index is decreased from 22.43% down to 1.04%, and results in an improvement in efficiency from 17.12% up to 20.10%. Following the understanding of defect-induced hysteresis, an approach to improve the hysteresis is provided, which can be integrated into the fabrication process and widely applied to enhance the performance of PSCs. 相似文献
6.
7.
基于行为效果的服务可替换性分析 总被引:1,自引:0,他引:1
服务可替换性分析是服务无缝集成与协作领域的一个重要问题,通过形式化的分析方法验证替换前后服务组合效果是否一致,有助于实现服务的动态组合.现有研究针对服务内部的操作和操作序列是否一致对服务的可替换性进行分析,会缩小可替换服务的空间.基于服务执行时的触发条件和结果提出了服务可替换性的定量判定方法.该方法采用有色Petri网对服务行为进行建模,将服务执行时的触发条件和结果定义为服务的行为效果,给出了行为效果一致的概念,并结合Petri网变换理论实现对服务可替换度的计算.最后通过定理证明了方法的有效性,这种定量分析的判定方法对于服务替换的正确建立和替换后组合服务的可靠执行具有重要作用. 相似文献
8.
A comparative study on UV light activated porous TiO2 and ZnO film sensors for gas sensing at room temperature 总被引:2,自引:0,他引:2
Hao ChenYuan Liu Changsheng Xie Jun WuDawen Zeng Yichuan Liao 《Ceramics International》2012,38(1):503-509
In order to find a new approach for screening the photoactivated gas sensing materials with high sensitivity, a comparative study was carried out. With the simple technique of screen printing, TiO2 and ZnO were used to fabricate the UV light activated gas sensors which were applied at room temperature. To facilitate the simultaneous measurements of the current transients of the two materials, they were printed on the same alumina substrate. Compared with ZnO, TiO2 exhibited a superior performance to ethanol and formaldehyde gases. It was found that the responses of TiO2 increased with the concentration of test gas and amounted to 224 and 1700 to 100 ppm ethanol and formaldehyde gases, respectively, while the responses of ZnO to 100 ppm ethanol and formaldehyde gases were 0.14 and 1.5, respectively. The mechanism of such a huge difference between TiO2 and ZnO was discussed in detail. Furthermore, it is suggested that metal oxide semiconductor with lower photo-to-dark current ratio can achieve higher photoactivated gas sensitivity. 相似文献
9.
利用米氏散射理论和时域有限差分(FDTD)软件计算了不同大小、形状和折射率粒子的前向散射光场分布,分析了通过光强度分布和非对称因子反演粒子相关信息、区分粒形的可行性。研制了一台利用增强型CCD相机在线采集单个气溶胶粒子在5°~19°前向散射角范围内光场图样的装置。8μm粒径的聚苯乙烯球形粒子散射图样实验结果与理论计算对比较为吻合,验证了该装置的有效性。应用该装置对不同形状的气溶胶粒子进行检测,结果表明能够从散射图像和反演计算结果区分出球形、杆状和其他形状粒子。 相似文献
10.
Au/TS‐1 catalyst for propene epoxidation with H2/O2: A novel strategy to enhance stability by tuning charging sequence
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Xiang Feng Yibin Liu Yichuan Li Chaohe Yang Zhihua Zhang Xuezhi Duan Xinggui Zhou De Chen 《American Institute of Chemical Engineers》2016,62(11):3963-3972
For propene epoxidation with H2 and O2, the catalytic performance of Au/TS‐1 catalyst is extremely sensitive to preparation parameters of deposition‐precipitation (DP) method. In this work, effect of charging sequence in DP process on catalyst structure and catalytic performance of Au/TS‐1 catalyst is first investigated. For different charging sequences, the compositions of Au complexes (e.g., [AuCl(OH)3]?) and pore property of TS‐1 (i.e., with or without H2O prefilling micropores) could affect the transfer of Au complexes into the micropores, resulting in different Au locations and thus significantly different catalytic performance. Notably, when TS‐1 is first filled with H2O and then mixed with Au complexes, the reduced Au/TS‐1 catalyst could expose Au nanoparticles on the external surface of TS‐1 and show high stability. The results provide direct evidence showing that micropore blocking is the deactivation mechanism. Based on the results, a simple strategy to design highly stable Au/Ti‐based catalysts is developed. © 2016 American Institute of Chemical Engineers AIChE J, 62: 3963–3972, 2016 相似文献