基于SVD和SSA-VMD降噪的轴承故障特征提取

针对强噪声背景下轴承故障特征提取困难的问题，提出一种基于奇异值分解和参数优化变分模态分解联合降噪的轴承故障特征提取方法(SSVMD)：首先，对原始信号进行奇异值分解(Singular Value Decomposition，SVD)处理，运用奇异值差分谱法选取有效奇异值并将原始信号重构得到初步降噪信号；其次，为防止故障信息丢失，将残余信号进行麻雀算法(Sparrow Search Algorithm，SSA)优化的变分模态分解(Variational Mode Decomposition，VMD）算法处理，得到最佳的模态个数K和惩罚参数α，选取峭度值最大、包络熵最小的IMF分量与初步降噪信号叠加得到最终降噪信号，并对信号进行包络分析；最后，通过仿真和试验数据分析得出，该方法能在信噪比很低的情况下降低噪声含量并提取轴承故障特征，为设备的状态监测和故障诊断提供理论依据。     

南美白对虾肝胰腺蛋白提取方法优化及无水保活环境胁迫对细胞凋亡蛋白的影响

为提高Western Blotting结果的可靠性，以蛋白溶出率和凝胶电泳蛋白条带完整性为指标，比较提取液种类、研磨方式、酶抑制剂种类及其体积分数和提取时间对南美白对虾肝胰腺蛋白提取效果的影响。采用优化后的提取方法获得高质量蛋白样品，并采用Western Blotting法分析无水环境胁迫后南美白对虾肝胰腺组织中细胞凋亡信号通路相关蛋白的表达水平。结果表明：RIPA裂解液作为提取溶剂所得的蛋白溶出率高于水提和磷酸盐缓冲液，电动匀浆和液氮研磨所得蛋白条带更完整，4%蛋白酶磷酸酶混合抑制剂能有效抑制肝胰腺内源酶引起的蛋白降解；采用Western Blotting法分析无水保活期间南美白对虾肝胰腺蛋白，发现低温诱导休眠的同时会引起细胞轻微凋亡，且凋亡水平呈应激时间依赖性增加，环境胁迫解除后有所回调。     

Mutual information maximizing GAN inversion for real face with identity preservation

Recent generative adversarial networks (GANs) have yielded remarkable performance in face image synthesis. GAN inversion embeds an image into the latent space of a pretrained generator, enabling it to be used for real face manipulation. However, current inversion approaches for real faces suffer the dilemma of initialization collapse and identity loss. In this paper, we propose a hierarchical GAN inversion for real faces with identity preservation based on mutual information maximization. We first use a facial domain guaranteed initialization to avoid the initialization collapse. Furthermore, we prove that maximizing the mutual information between inverted faces and their identities is equivalent to minimizing the distance between identity features from inverted and original faces. Optimization for real face inversion with identity preservation is implemented on this mutual information-maximizing constraint. Extensive experimental results show that our approach outperforms state-of-the-art solutions for inverting and editing real faces, particularly in terms of face identity preservation.     

Data fusion and transfer learning empowered granular trust evaluation for Internet of Things

In the Internet of Things (IoT), a huge amount of valuable data is generated by various IoT applications. As the IoT technologies become more complex, the attack methods are more diversified and can cause serious damages. Thus, establishing a secure IoT network based on user trust evaluation to defend against security threats and ensure the reliability of data source of collected data have become urgent issues, in this paper, a Data Fusion and transfer learning empowered granular Trust Evaluation mechanism (DFTE) is proposed to address the above challenges. Specifically, to meet the granularity demands of trust evaluation, time–space empowered fine/coarse grained trust evaluation models are built utilizing deep transfer learning algorithms based on data fusion. Moreover, to prevent privacy leakage and task sabotage, a dynamic reward and punishment mechanism is developed to encourage honest users by dynamically adjusting the scale of reward or punishment and accurately evaluating users’ trusts. The extensive experiments show that: (i) the proposed DFTE achieves high accuracy of trust evaluation under different granular demands through efficient data fusion; (ii) DFTE performs excellently in participation rate and data reliability.     

川东南丁山地区燕山期—喜马拉雅期差异构造-热演化与页岩气保存

中国的海相富有机质页岩经历了多期构造改造，其含气性具有明显的差异。页岩气在不同构造演化阶段的保存条件是揭示页岩气差异富集机理的关键科学问题之一，开展构造-热演化研究可以明确其热演化史和构造隆升-剥蚀过程，为其评价提供演化格架。研究以丁山地区下古生界页岩为对象，联合磷灰石裂变径迹、磷灰石（U-Th）/He和锆石（U-Th）/He等多个古温标反演热演化史，结合镜质体反射率重建的最高古地温剖面，对丁山地区燕山期以来的差异构造隆升过程和剥蚀量进行了恢复，并在此基础上结合流体包裹体分析对丁山地区龙马溪组页岩的压力演化过程进行了模拟；根据页岩在埋藏—抬升过程中的温、压演化特征，定量表征了不同抬升阶段页岩含气量的变化，建立了龙马溪组页岩"埋藏—生烃—抬升"的演化格架。分析表明，丁山地区在燕山期和喜马拉雅期经历了不同的构造隆升过程。燕山期表现为"早期快速隆升—晚期缓慢隆升"的分段隆升，具有自NW向SE递进隆升且隆升幅度逐渐增大的特征；喜马拉雅期表现为整体快速隆升。燕山期是丁山地区产生差异构造隆升的主要时期。受这种差异构造隆升-剥蚀作用的影响，龙马溪组页岩的降温、降压过程和页岩气的散失过程具有明显的差异。燕山期的差异构造隆升是造成丁山地区龙马溪组页岩含气性呈平面分带的主要原因。     

Islam,Heritage, and Preservation: An Untidy Tradition

Abstract

In this article I argue that the study of cultural heritage preservation practices in the context of Muslim societies has been constructed—and obstructed—through specific historical trajectories and challenges. These originate within the field of cultural heritage preservation, through its own history and principles which have complicated the interplay between heritage and religious values and uses. As a result, situated studies of preservation practices in and by Muslim communities are in their infancy. In this article I revisit the points of contact between the emergence of a Eurocentric preservation dogma and its encounter with different articulations and practices related to Islam that are now approached as part of heritage assemblages and debates. I consider specific biases inherent in these discourses and propose, as a result, to approach the study of Islam and heritage in its own terms—rather than as an alternative to Western preservation paradigms.     

Hydrocarbon preservation and formation water geochemistry in abnormal pressure system in the Bawu area of Lishu depression,Songliao Basin,China

The hydrocarbon production in the Bawu area of Lishu Depression is high. However, the Bawu area has undergone three main tectonic movements, the strata were strongly uplifted and eroded, and the fractures were extremely developed. The conditions of hydrocarbon preservation have become intricate. In this study, by analyzing isotopes compositions and geochemical features of formation water, and the characteristics of formation pressure, the hydrocarbon preservation can be deduced. The subnormal and lower normal pressure zones (away from Xiaokuan Fault) of Yingcheng and Shahezi Formations are relatively closed and more conducive to hydrocarbon preservation.     

利用地震品质因子Q比例的分布特征预测南川页岩气藏保存条件

根据地震数据、地质资料和地震属性，开展了南川地区五峰组-龙马溪组下部页岩的地震品质因子Q平面上分布与页岩气保存条件评价研究。针对南川地区页岩气开发中的断裂破碎带，提出了一种获取稳定品质因子Q比例及界限的工作流程和相应的迭代算法。研究表明，地震品质因子Q比例的分布可以快速、直观识别出断裂破碎带的内幕特征与不同类型页岩分布区。其中，断裂破碎带页岩区的品质因子Q比例总体上偏小，大多低于0.2，局部超过0.5，平面上分布杂乱、碎斑状；页岩呈北东向展布的条带，被断裂所撕裂、破碎，保存条件较差。稳定分布的页岩区的品质因子Q比例是较高的，超过0.7，平面变化稳定，没有突变现象，保存条件好。微裂缝发育的页岩区的品质因子Q比例具有渐变的趋势性，品质因子Q比例的分布从该页岩区的边部0.7向中部有规律地减小至0.1，保存条件最佳。实践证明，高产气井大多位于稳定分布的页岩区或内部微裂隙发育的稳定页岩区，地震品质因子Q比例研究方法对页岩气保存评价与开发井优化部署是一个实用工具。     

赵庄井田煤层气成藏条件研究

煤层气成藏条件研究是有效划分成藏类型或含气系统，煤层气富集高渗有利区预测、评价及优选的关键基础工作。基于赵庄井田煤层气地质条件及相关测试资料，借鉴前人研究成果，从煤生烃、煤层气储集和煤层气封盖保存条件等方面对赵庄井田煤层气成藏条件进行了研究。研究结果表明:煤中丰富的生烃物质在良好的生烃动力作用下，提高了生烃率和生烃量，为煤层气成藏提供了基础条件；煤变质程度高，促使煤中微小孔隙发育，煤层气储集能力增强和储集空间增大，有利于煤层气大量储存和富集；煤层埋深、围岩特性、构造及地下水径流等地质条件的有机匹配，为煤层气成藏提供了良好的封盖保存条件，是煤层气成藏的关键因素。     

抗菌肽应用于食品中的研究现状及面临的挑战

食品安全问题一直为人们所关注,其中微生物污染是导致食品腐败变质的主要原因。抗菌肽来源广泛,抑菌谱广,杀菌速度快,可以较好地控制食品中腐败微生物的滋生;对pH值、蛋白酶和热处理有较好的稳定性,在成分复杂的食品体系中有一定的适用性;由于其抑菌机理特殊,不易产生耐药性;部分具有抗氧化和提高免疫力等多种功能,对人体具有一定的保健作用。抗菌肽的以上特点满足了人们对新型防腐保鲜剂的多种需求,有望在食品工业上发挥重大作用。因此,在抗菌肽的生物学功能以及抗菌肽保鲜机理简单介绍的基础上,对抗菌肽应用于不同食品中的研究现况进行详细综述,最后对抗菌肽在食品中应用目前存在的问题和发展方向提供了思考。