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退市新规提高了审计收费吗?

审计研究 2024年第5期 75-88页

作者：王跃堂马靓沈小燕南京大学商学院 210093 河南大学国际商学院南通大学商学院 226019

为切实提高资本市场的有效性,我国在注册制上市制度出台后,将作为配套制度的退市制度也进行了相应改革。退市新规进一步细化了相关指标,强化了审计师的工作职责,从而提高了审计工作的压力和风险,这是否会对审计收费产生影响?本文以2020... 详细信息

为切实提高资本市场的有效性,我国在注册制上市制度出台后,将作为配套制度的退市制度也进行了相应改革。退市新规进一步细化了相关指标,强化了审计师的工作职责,从而提高了审计工作的压力和风险,这是否会对审计收费产生影响?本文以2020年底出台的退市新规为研究契机,选取2016-2022年A股上市公司为样本,研究显示,退市新规通过加大有退市风险公司的审计风险和审计师声誉风险,使得审计师增加了额外的审计收费以弥补过高风险。在非国企、内控水平较差、机构投资者占比较少和媒体关注较少的公司中提高更大,随着审计收费的提高,审计效率上升,审计激进度缓解,审计质量提升。本文从退市制度变革角度丰富了审计收费影响因素的研究,同时为完善退市制度提供了审计市场层面的证据。

关键词：退市新规审计收费审计风险审计师声誉

Continual learning fault diagnosis:A dual-branch adaptive aggregation residual network for fault diagnosis with machine increments

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Chinese Journal of Aeronautics 2023年第6期36卷 361-377页

作者： Bojian chen Changqing shen Juanjuan SHI Lin KONG Luyang TAN Dong WANG Zhongkui ZHU School of Rail Transportation Soochow UniversitySuzhou 215131China China Chang Guang Satellite Technology CO.LTD Changchun 130102China Department of Industrial Engineering and Management and in the State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong UniversityShanghai 200030China

As a data-driven approach, Deep Learning(DL)-based fault diagnosis methods need to collect the relatively comprehensive data on machine fault types to achieve satisfactory performance. A mechanical system may include multiple submachines in the real-world. During condition monitoring of a mechanical system, fault data are distributed in a continuous flow of constantly generated information and new faults will inevitably occur in unconsidered submachines, which are also called machine increments. Therefore, adequately collecting fault data in advance is difficult. Limited by the characteristics of DL, training existing models directly with new fault data of new submachines leads to catastrophic forgetting of old tasks, while the cost of collecting all known data to retrain the models is excessively high. DL-based fault diagnosis methods cannot learn continually and adaptively in dynamic environments. A new Continual Learning Fault Diagnosis method(CLFD) is proposed in this paper to solve a series of fault diagnosis tasks with machine increments. The stability–plasticity dilemma is an intrinsic issue in continual learning. The core of CLFD is the proposed Dual-branch Adaptive Aggregation Residual Network(DAARN).Two types of residual blocks are created in each block layer of DAARN: steady and dynamic blocks. The stability–plasticity dilemma is solved by assigning them with adaptive aggregation weights to balance stability and plasticity, and a bi-level optimization program is used to optimize adaptive aggregation weights and model parameters. In addition, a feature-level knowledge distillation loss function is proposed to further overcome catastrophic forgetting. CLFD is then applied to the fault diagnosis case with machine increments. Results demonstrate that CLFD outperforms other continual learning methods and has satisfactory robustness.

关键词： Catastrophic forgetting Continual learning Fault diagnosis Knowledge distillation Machine increments Stability-plasticity dilemma

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从影像索引到象征系统:符号学纪实理论探赜

广州大学学报（社会科学版） 2024年第3期23卷 133-144页

作者：沈钰扉北京大学艺术学院北京100871

长久以来,以巴赞、克拉考尔为代表的纪实观念基本垄断了学界对于电影纪实理论的理解,而电影纪实的实践则常被限定于纪录片或逼真摹写现实的影片类型当中。事实上,纪实学派之后的结构主义思潮以及符号学并未放弃对电影纪实魔力的理论重释... 详细信息

长久以来,以巴赞、克拉考尔为代表的纪实观念基本垄断了学界对于电影纪实理论的理解,而电影纪实的实践则常被限定于纪录片或逼真摹写现实的影片类型当中。事实上,纪实学派之后的结构主义思潮以及符号学并未放弃对电影纪实魔力的理论重释,其惯例系统、幻觉、想象等概念也大都渊源有自。经由米特里、第一符号学乃至第二符号学的改造,电影纪实性观念不断突破早期的概念边界,随技术、思潮之代序而变迁,与不断更新的电影现象相适配。探究该时期影像纪实理论之内核,可以揭示其潜在的思想流变,暴露其局限,补足我们对这段“折跃”式影像纪实观念的理解的缺失。

关键词：纪实性让·米特里克里斯蒂安·麦茨电影符号学实在界

Detection of biosignatures in Terrestrial analogs of Martian regions:Strategical and technical assessments

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Earth and Planetary Physics 2022年第5期6卷 431-450页

作者： JianXun shen Yan chen Yu Sun Li Liu YongXin Pan Wei Lin Key Laboratory of Earth and Planetary Physics Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijing 100049China

For decades, the search for potential signs of Martian life has attracted strong international interest and has led to significant planning and scientific implementation. Clearly, in order to detect potential life signals beyond Earth, fundamental questions, such as how to define such terms as “life” and “biosignature”, have been given considerable attention. Due to the high costs of direct exploration of Mars, Mars-like regions on Earth have been invaluable targets for astrobiological research, places where scientists could practice the search for “biosignatures” and refine ways to detect them. This review summarizes scientific instrumental techniques that have resulted from this work. Instruments must necessarily be our “eyes” and “hands” as we attempt to identify and quantify biosignatures on *** devices that can be applied in astrobiology include mass spectrometers and electromagnetic-spectrum-based spectrometers,redox potential indicators, circular dichroism polarimeters, in situ nucleic acid sequencers, life isolation/cultivation systems, and *** devices and how to interpret the data they collect have been tested in Mars-analog extreme environments on Earth to validate their practicality on Mars. To anticipate the challenges of instrumental detection of biosignatures through the full evolutionary history of Mars, Terrestrial Mars analogs are divided into four major categories according to their similarities to different Martian geological periods(the Early-Middle Noachian Period, the Late Noachian-Early Hesperian Period, the Late Hesperian-Early Amazonian Period, and the Middle-Late Amazonian Period). Future missions are suggested that would focus more intensively on Mars’ Southern Hemisphere, once landing issues there are solved by advances in spacecraft engineering, since exploration of these early terrains will permit investigations covering a wider continuum of the shifting habitability of Mars through its geological history. Finally,

关键词： biosignature detection framework extraterrestrial life evolutionary history of Mars field trial instrument Mars analog

工业园区大气污染物排放总量核算模型优化算法反演性能对比

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环境工程技术学报 2024年第4期14卷 1232-1238页

作者：赵瀚森刘峰均张夏夏吴柏莹沈怡秀高逸飞陈高江苏省生态环境监测监控有限公司江苏省环保集团有限公司江苏省生态环境大数据有限公司

基于工业园区污染物排放总量核算模型,以东南沿海某重点石化产业基地VOCs的排放总量核算为例,对比研究了Nelder-Mead单纯形法(NM)、双模退火优化算法(DA)、粒子群优化算法(PSO)3种优化算法和通过偏差平方和(目标函数1)、对数变换(目标函... 详细信息

基于工业园区污染物排放总量核算模型,以东南沿海某重点石化产业基地VOCs的排放总量核算为例,对比研究了Nelder-Mead单纯形法(NM)、双模退火优化算法(DA)、粒子群优化算法(PSO)3种优化算法和通过偏差平方和(目标函数1)、对数变换(目标函数2)、双曲余弦变换(目标函数3)构建的3种优化目标函数在不同随机误差强度和失效站点数量下的反演性能。结果表明:PSO算法的反演性能与粒子数量有关,但整体表现不适用于当前条件下的反演优化,NM和DA优化算法具有较好的反演准确性(MARE<30%),但NM优化算法的反演计算效率约为DA优化算法的11~20倍,NM优化算法反演性能最好;3种优化目标函数均适用于当前条件下的反演优化(MARE<30%),其中目标函数1和目标函数3在随机误差强度、失效站点数量较小的情况下反演性能更好,而目标函数2在随机误差强度、失效站点数量相对较大的情况下反演性能更好。

关键词：工业园区污染排放总量核算优化算法优化目标函数源参数反演

Regulating interfacial morphology and charge-carrier utilization of Ti_(3)C_(2)modified all-sulfide CdS/ZnIn_(2)S_(4)S-scheme heterojunctions for effective photocatalytic H_(2) evolution

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Journal of Materials Science & Technology 2022年第17期112卷 85-95页

作者： Junxian Bai Weilin chen Rongchen shen Zhimin Jiang Peng Zhang Wei Liu Xin Li Institute of Biomass Engineering Key Laboratory of Energy Plants Resource and UtilizationMinistry of Agriculture and Rural AffairsSouth China Agricultural UniversityGuangzhou 510642China College of Materials and Energy South China Agricultural UniversityGuangzhou 510642China State Centre for International Cooperation on Designer Low-Carbon and Environmental Materials(CDLCEM) School of Materials Science and EngineeringZhengzhou UniversityZhengzhou 450001China

The separation efficiency of electrons and holes and the enhancement of the surface reductive reaction in the metal sulfide semiconductor photocatalysts are important factors in boosting photocatalytic H_(2)evolution from *** control of both interface morphology and the charge-carrier utilization of metal sulfide-based photocatalysts can effectively improve the separation efficiency of electrons and holes and increase the surface reaction active sites,which are considered to be effective methods to improve the photocatalytic activity of ***,the Ti_(3)C_(2)(Mxene)modified all-sulfide 2D/2D Sscheme heterojunction Ti_(3)C_(2)/Zn In_(2)S_(4)(ZIS)/CdS composite material was firstly synthesized by a two-step solvothermal *** formation of all-sulfide S-scheme heterojunction improves the efficiency of electron-hole *** intimate 2D/2D van der Waals structure provides a strong interaction force and a large contact area to enhance charge *** addition of 2D Ti_(3)C_(2)forms the accumulation layer,reducing the recombination of electrons and *** the synergistic promotion,the highest hydrogen production of the prepared Ti_(3)C_(2)/ZIS/CdS composite photocatalyst could reach 8.93 mmol/h/*** work not only enriches the photocatalytic systems through integrating the ohmic junction and the 2D/2D all-sulfide S-scheme heterojunction,but also provides a satisfactory design strategy for engineering interfacial morphology and charge-carrier utilization.

关键词： S-scheme heterojunction Photocatalytic hydrogen evolution Ti_(3)C_(2)Mxene-based ohmic junction ZnIn_(2)S_(4)nanosheets 2D/2D van der Waals interfaces

Transcriptome Analysis of Pacific White Shrimp (Litopenaeus vannamei) Under Prolonged High-Salinity Stress

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Journal of Ocean University of China 2022年第2期21卷 430-444页

作者： LI Yuquan chen Yigeng CUI Yanting shen Min WANG Renjie WANG Zhongkai School of Marine Science and Engineering Qingdao Agricultural UniversityQingdao 266109China Shandong Key Laboratory of Disease Control in Mariculture Marine Biology Institute of Shandong ProvinceQingdao 266104China

The Pacific white shrimp(Litopenaeus vannamei)is a marine species commonly farmed *** northern China,it has been increasingly cultured in high-salinity waters(>40),but exhibits poor growth *** this study,postlarval shrimps were acclimated to salinity 55,cultivated for 3 months at this salinity,and compared with a control group reared at general salinity ***,high-throughput RNA sequencing was applied to compare the transcriptomic responses in the gills and hepatopancreas of the shrimps in the control group and the treatment group,while the weights of the shrimps in these two groups were significantly *** results revealed that 11834 and 2115 genes were significantly differentially expressed in the gills and hepatopancreas,***,enrichment analysis of the differentially expressed genes indicated that osmoregula-tion-associated Gene Ontology terms and KEGG pathways were similar between the two subgroups of the shrimp maintained at high salinity,suggesting that the growth rate of shrimp at high salinity is independent of ***,examination of the shrimp with different growth rates(i.e.,weights)at high salinity revealed molt-associated processes,namely,increased expression of ecdysone response genes and downstream effector genes in the gills and hepatopancreas of slow-growing shrimp,suggesting a role of the molt-associated processes in the regulation of shrimp growth at high ***,we not only report adaptive transcriptomic responses of *** to prolonged high-salinity stress,but also provide new insights into the shrimp growth regulation at high salinity.

关键词： salinity growth osmoregulation transcriptome Litopenaeus vannamei

Arc erosion behavior of a nanocomposite W-Cu electrical contact material

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Rare Metals 2006年第1期25卷 37-42页

作者： chen Wenge KANG Zhanying shen Hongfang DING Bingjun School of Materials Science and Engineering Xi＇an University of Technology Xi＇an 710048 China Department of Materials Physics Xi＇an Jiaotong University Xi＇an 710049 China

The erosion behavior of a nanocomposite W-Cu material under arc breakdown was investigated. The arc erosion rates of the material were determined, and the eroded surfaces and arc erosion mechanisms were studied by scanning eleclion microscopy. It is concluded that the nanocomposite W-Cu electrical contact material shows a characteristic of spreading arcs. The arc breakdown of a commercially used W-Cu alloy was limited in a few areas, and its average arc erosion rate is twice as large as that of the former. Furthermore, it is also proved that the arc extinction ability and arc stability of the nanocomposite W-Cu material are excellent, and melting is the major failure modality in the make-and-break operation of arcs.

关键词： arc erosion W-Cu alloy contact materials nanocomposite

Machine learning in materials genome initiative:A review

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Journal of Materials Science & Technology 2020年第22期54卷 113-122页

作者： Yingli Liu chen Niu Zhuo Wang Yong Gan Yan Zhu Shuhong Sun Tao shen Faculty of Information Engineering and Automation Kunming University of Science and TechnologyKunming650500China Computer Technology Application Key Lab of Yunnan Province Kunming University of Science and TechnologyKunming650500China Light Alloy Research Institute Central South UniversityChangsha410083China Chinese Academy of Engineering Beijing100088China Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming650093China chengdu MatAi Technology Co. LtdChengdu610041China

Discovering new materials with excellent performance is a hot issue in the materials genome *** experiments and calculations often waste large amounts of time and money and are also limited by various conditions. Therefore, it is imperative to develop a new method to accelerate the discovery and design of new materials. In recent years, material discovery and design methods using machine learning have attracted much attention from material experts and have made some progress. This review first outlines available materials database and material data analytics tools and then elaborates on the machine learning algorithms used in materials science. Next, the field of application of machine learning in materials science is summarized, focusing on the aspects of structure determination, performance prediction, fingerprint prediction, and new material discovery. Finally, the review points out the problems of data and machine learning in materials science and points to future research. Using machine learning algorithms, the authors hope to achieve amazing results in material discovery and design.

关键词： Materials genome initiative(MGI) Materials database Machine learning Materials properties prediction Materials design and discovery