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为提高拉曼光纤放大器（RFA）的放大带宽和光纤通信系统的传输容量,利用4个不同波长的泵浦设计了带宽为100nm的宽带RFA。在对拉曼耦合波微分方程数值求解的同时,结合粒子群优化算法优化了4个泵浦的波长及功率,得到了3组平均开关增益分别为18.690 9、19.638 7和21.764 1dB,所对应的增益平坦度分别为0.879 7、0.914 4和0.945 2dB的优化结果。基于3组优化后的泵浦功率和泵浦波长,对粒子群优化算法的边界条件进行改进,进一步提升了RFA的性能,也使算法的性能得到改善。最终实现了增益为22.480 4dB、增益平坦度为0.696 3dB的宽带RFA。同时,对算法中的惯性权重和学习因子等参数进行了适当的调整,用来分析对比不同参数选择时优化结果如何变化,分析对比的结果为算法参数的选择提供了参考。

Potential knowledge can be extracted from the safety text of distant water fishing (DWF) vessels. However, the previous approaches have not yet been fully developed for the safety text of fishing vessels. Some challenges remained, such as the low accuracy of text classification, and insufficient depth of knowledge extraction. In this study, an analytical approach was proposed to combine text classification, knowledge mining, and co-occurrence network technology under the Cape Town Agreement(CTA) of 2012 . The text data on DWF vessel safety was also collected from the fishery management organizations, associations, and over 20 fishery enterprises from eight Chinese coastal provinces and cities, including Zhejiang, Shanghai, and Fujian. The DWF vessel safety corpus consisted of more than 5,000 valid questions and 100,000 characters. The analytical approach comprised three stages. Firstly, a hybrid deep learning model was developed using bidirectional encoder representations from transformers-text convolutional neural networks (BERT-TextCNN), according to the characteristics of DWF vessel safety text, such as diverse data types, sparse data features, and fuzzy boundaries. The character vectors were generated to extract the contextual semantic and deep syntactic information of the text using BERT during text representation. Multiple convolutional kernels of TextCNN were utilized to spatially model the generated character vectors and then to extract the local features for the accurate classification of safety theme. Secondly, term rrequency-inverse document frequency (TFIDF) was employed to extract the key safety knowledge of fishing vessels, considering the importance and prevalence of knowledge within each safety theme. Finally, a co-occurrence network was constructed to visualize the safety knowledge of fishing vessels, including distributional patterns and interconnections. The results show that the BERT-TextCNN model achieved an accuracy, macro average recall rate, and macro average F1 value of 98.20%, 98.02%, and 98.05%, respectively. The performance outperformed the other 17 comparative models, which utilized three text representations (BERT, Word2vec, and Character embedding) and six neural networks (TextCNN, Softmax, DPCNN, BiLSTM-Attention, RCNN, and Transformer). Meanwhile, the theme-based knowledge mining and analytical approach achieved clear rankings of DWF vessel compliance and safety management knowledge, as well as relationship networks crossing ten safety knowledge themes of fishing vessels, including provisions, structure, stability, electrical installations, fire protection, crew protections, life-saving equipment, emergency procedures, wireless communication, and shipborne navigation equipment. Intelligent safety knowledge services and decision-making tools were obtained to improve the compliance level and safety management efficiency in DWF. The finding can provide a strong reference to promote the application and development of knowledge service systems and the smart fishing industry. [ABSTRACT FROM AUTHOR]

多芯光纤可大幅提高光纤的传输容量,但芯间串扰会导致网络资源分配面临更大挑战。文章分析了多芯光纤网络的路由、纤芯选择和频谱分配问题,建立了考虑纤芯间串扰的优化模型,以最小化网络最大占用频隙号为优化目标,首次设计了一种基于协同进化的优化算法,以解决路由、纤芯选择和频谱分配问题。根据最大请求优先排序策略将连接请求降序排列,利用整数编码分别为路由和纤芯选择设立不同种群,结合单点交叉与均匀变异,采用差异化的精英保留进化策略,以搜索路由、纤芯选择和频谱分配问题的全局最优解。完成所提算法在两种不同网络拓扑下的性能评估,实验结果表明,所提算法可实现网络频谱资源的高效利用,业务承载分布更均衡。

We present a magnetic scanning microscope equipped with a nitrogen-vacancy (NV) center scanning probe that has the ability to mechanically tune the strain of soft matter in-situ. The construction of the microscope and a continuous strain-tuning sample holder are discussed. An optically detected magnetic resonance protocol utilized in the imaging is described. In order to show the reliability of this microscope, the strain conduction is estimated with finite element simulation, and x-ray diffraction is required for calibration when freestanding crystal films are under consideration. A magnetic imaging result is displayed to demonstrate the nano-scale imaging capability. The microscope presented in this work is helpful in studying strain-coupled magnetic physics such as magnetic phase transition under strain and strain-tuned cycloidal orientation tilting. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The past two decades have seen the emergence of a great amount of simulacrascape, which reshapes China's urban space economically, socially, culturally and politically. Unfortunately, as a new genre of urban space, the simulacrascape has not attracted widespread attention from scholars. This study shed light on a micro simulacrascape – the Foshan Japan Street, to examine its rising reasons and image building under the influence of new media. Located in Da‐ li town, Nanhai district, Foshan city, the Foshan Japan Street is a pedestrian street approximate one-hundred-meter away from Wanda Plaza, which is constructed by the Wanda group and opened in the August of 2020. This paper was based on field investigation conducted in October and December of 2020, and on web-based text data drawn from various social media platforms, such as Xiaohongshu, Weibo and Bilibili, which are very popular among the youth for online discussion and communication. This study started with clarifying the imitated elements and characteristics of the Foshan Japan Street through field investigation, followed by the discussion of rea‐ sons for the emergence of Foshan Japan Street. Secondly, this study explored the image building process of Foshan Japan Street that was influenced by new social media through analyzing web based text data. Finally, this study concluded with the discussion of the reasons for the opposite images of the Foshan Japan Street. In sum, the study found that: (1)the imitated elements of Foshan Japan Street are inspired by the urban Streetscape from Japan and ACGN subculture, but in reality, the Foshan Japan Street has become a cultural borrowing photo hotspot, which attracts a massive amount of young people for photo taking and online tagging; (2)the capital competition and new socializing ways are the two main driving factors for the emergence of the Foshan Ja‐ pan Street. In addition, the change of tourism environment influenced by the new crown pneumonia also plays an important role, as it largely promotes the clout and publicity of the Foshan Japan Street; (3) the image building of the Foshan Japan Street is influenced largely by the new media. Under the influence of new media, discussions of the Foshan Japan Street by users of social platform focused primarily on two aspects, including cultural authenticity, and plagiarism and infringement, these discussions produced coexisting positive and negative images of the Foshan Japan Street at present. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Eastern Liaoning University (Natural Science Edition) is the property of Department of Journal of Eastern Liaoning University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In ander to maly the effects of lantham exposure on reaal structure and function of growing nts, 40 adult female mts were randcenly divided into control group, extremely low, low, medium and high lanthanum chloride (Lall,) exposure groups. The offspring drank water solution with 1.25, 2.50, 5.00 and 10.00 g/L LaCl, after weaning. The body weight and kidney weight of the offspring in each group were recorded. The kidney structural changes and the changes of renal function indicators were detected. The results showed that the body weight of the offspring decreased (P<0.05), and the reaal coefficient increased (P<0.05) with the increasing of lanthanum exposure dose. The proliferation of glomerular mesangial cells and endothelial cells were observed in 2.50 g/L LaCl, group, the glomerular inflammatory cells and cellulose exudation were observed in 5.00 g/L. LaCl, group, the hyaline degeneration of renal glomerali, the degeneration and necrosis of renal tubular epithelial cells were observed in 10.00 g/L LaCl, group. The serum content of BUN in LaCly exposed offspring increased (P < 0. 05) while there was no difference in serum creatinine content of the offsprings (P>0.05). Therefore, exposure to lanthanum chloride can lead to changes of renal tissue structure and decrease renal function during growth and de velopment period. [ABSTRACT FROM AUTHOR]

Copyright of Acta Agriculturae Zhejiangensis is the property of Acta Agriculturae Zhejiangensis Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Eastern Liaoning University (Natural Science Edition) is the property of Department of Journal of Eastern Liaoning University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Frequent itemsets mining for uncertain data has been studied extensively. For uncertain data which recorded private information of users, an attacker made use of background knowledge to obtain private information of users by analyzing frequent itemsets mined from uncertain data. In this regard, this paper proposed a new algorithm, denoted as FIMUDDP (frequent itemsets mining for uncertain data based on differential privacy) , to mine the top K most frequent itemsets based on expected support from uncertain data and satisfy differential privacy. FIMUDDP algorithm applied exponential mechanism and Laplace mechanism in differential privacy to ensure differential privacy for the top K most frequent itemsets based on expected supports of these frequent itemsets respectively. Finally, through analyzing FIMUDDP from theory and experiment evaluation, the results demonstrate the effectiveness of FIMUDDP. [ABSTRACT FROM AUTHOR]

Object ives To revise the second version of the Quality of Life Instrument for Cancer Patients-Stomach Cancer and to discuss the preliminary applications of the instrument. Methods A combination of common modules plus specific modules， literature review and analysis of Chinese culture， programmed decision processes were conducted， including information collection， group discussion， statistical analysis， and pre-tests， to revise items of the QOL instrument for patient with stomach cancer. Statistic methods of variation coefficient， correlation coefficient and variance analysis were applied. Results （1） A 23-item specific module was formed by reviewing the literature and collecting the opinions of core group. Then 20-item specific module was picked after further group discussion. （2） The final 10-item specific module was developed based on the data of pre-survey. Conclusion Development of the specific items of QLICP-ST （V 2.0） is clinically relevant and can be used for assessing the quality of life of gastric cancer patients in China as a clinical tool. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Geology & Recovery Efficiency is the property of Petroleum Geology & Recovery Efficiency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)