191 research outputs found

    Genetic inter-relationships among Chinese wild grapes based on SRAP marker analyses

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    Sequence-Related Amplified Polymorphism (SRAP) markers were used to assess genetic inter-relationships among 39 grape genotypes. These included 22 indigenous Chinese grape species/varieties, the north American V. riparia and the European V. vinifera L. 'Thompson seedless' and 'Pinot noir'. Of the 72 SRAP primer combinations tested, 25 primers generated 135 reliable bands, with an average of 5.52 bands per primer pair. Further analysis shows that 106 of 135 bands were generated by 25 polymorphic primer pairs, with a polymorphism efficiency of 79 %. The similarity coefficients of SRAP polymorphism varied from 0.463 to 0.981 among the genotypes analysed. A dendrogram analysis divided the 39 Vitis accessions into 21 groups with similarity coefficients of 0.83. It reveals broadly similar genetic relationships among the genotypes examined to those previously determined using classical taxonomic methods. Our results define V. heyneana subsp. ficifolia and V. baihensis as subspecies of V. heyneana and V. bashanica, respectively. We question the placement of V. davidii var. cyanocarpa and V. davidii var. ningqiangensis as varieties in V. davidii

    Unsupervised Boundary-Aware Language Model Pretraining for Chinese Sequence Labeling

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    Boundary information is critical for various Chinese language processing tasks, such as word segmentation, part-of-speech tagging, and named entity recognition. Previous studies usually resorted to the use of a high-quality external lexicon, where lexicon items can offer explicit boundary information. However, to ensure the quality of the lexicon, great human effort is always necessary, which has been generally ignored. In this work, we suggest unsupervised statistical boundary information instead, and propose an architecture to encode the information directly into pre-trained language models, resulting in Boundary-Aware BERT (BABERT). We apply BABERT for feature induction of Chinese sequence labeling tasks. Experimental results on ten benchmarks of Chinese sequence labeling demonstrate that BABERT can provide consistent improvements on all datasets. In addition, our method can complement previous supervised lexicon exploration, where further improvements can be achieved when integrated with external lexicon information.Comment: 12 pages, 2 figures, 7 tables, EMNLP 202

    Fatigue safety monitoring and assessment of short and medium span concrete girder bridges

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    Concrete bridge is widely used in highway infrastructure in China, especially in short and medium span bridges. Concrete bridges are prone to fatigue failure under the coupled actions of repeated vehicles loads, environment and material degradation. In recent years, the traffic volume and vehicle weights of highway bridges have been continuously increasing, so concrete bridge fatigue problem becomes more serious. This paper introduces advanced fatigue safety monitoring techniques and fatigue performance assessment methods for short and medium span concrete girder bridges. Weigh-in-motion (WIM) system was used to record the real traffic volume, and then the acquired load spectrum was applied on typical concrete bridges through Matlab to analyze the fatigue performance of different bridge types. From the analysis results, several typical short and medium span concrete girder bridges are selected to conduct long-term service monitoring. The cross section types include hollow slab girder, T-girder and short box girder, and the structure types contain simple supported bridge and continuous girder bridge. WIM technique, dynamic strain monitoring technique and acoustic emission technique are used to monitor the key details. Fatigue performance is assessed and analyzed based on monitoring data, considering traffic increase, overload and corrosion factors

    Fine-grained ship image recognition based on BCNN with inception and AM-Softmax

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    The fine-grained ship image recognition task aims to identify various classes of ships. However, small inter-class, large intra-class differences between ships, and lacking of training samples are the reasons that make the task difficult. Therefore, to enhance the accuracy of the fine-grained ship image recognition, we design a fine-grained ship image recognition network based on bilinear convolutional neural network (BCNN) with Inception and additive margin Softmax (AM-Softmax). This network improves the BCNN in two aspects. Firstly, by introducing Inception branches to the BCNN network, it is helpful to enhance the ability of extracting comprehensive features from ships. Secondly, by adding margin values to the decision boundary, the AM-Softmax function can better extend the inter-class differences and reduce the intra-class differences. In addition, as there are few publicly available datasets for fine-grained ship image recognition, we construct a Ship-43 dataset containing 47,300 ship images belonging to 43 categories. Experimental results on the constructed Ship-43 dataset demonstrate that our method can effectively improve the accuracy of ship image recognition, which is 4.08% higher than the BCNN model. Moreover, comparison results on the other three public fine-grained datasets (Cub, Cars, and Aircraft) further validate the effectiveness of the proposed method

    Intersectional Two-sided Fairness in Recommendation

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    Fairness of recommender systems (RS) has attracted increasing attention recently. Based on the involved stakeholders, the fairness of RS can be divided into user fairness, item fairness, and two-sided fairness which considers both user and item fairness simultaneously. However, we argue that the intersectional two-sided unfairness may still exist even if the RS is two-sided fair, which is observed and shown by empirical studies on real-world data in this paper, and has not been well-studied previously. To mitigate this problem, we propose a novel approach called Intersectional Two-sided Fairness Recommendation (ITFR). Our method utilizes a sharpness-aware loss to perceive disadvantaged groups, and then uses collaborative loss balance to develop consistent distinguishing abilities for different intersectional groups. Additionally, predicted score normalization is leveraged to align positive predicted scores to fairly treat positives in different intersectional groups. Extensive experiments and analyses on three public datasets show that our proposed approach effectively alleviates the intersectional two-sided unfairness and consistently outperforms previous state-of-the-art methods.Comment: accepted by WWW202

    A Situation-aware Enhancer for Personalized Recommendation

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    When users interact with Recommender Systems (RecSys), current situations, such as time, location, and environment, significantly influence their preferences. Situations serve as the background for interactions, where relationships between users and items evolve with situation changes. However, existing RecSys treat situations, users, and items on the same level. They can only model the relations between situations and users/items respectively, rather than the dynamic impact of situations on user-item associations (i.e., user preferences). In this paper, we provide a new perspective that takes situations as the preconditions for users' interactions. This perspective allows us to separate situations from user/item representations, and capture situations' influences over the user-item relationship, offering a more comprehensive understanding of situations. Based on it, we propose a novel Situation-Aware Recommender Enhancer (SARE), a pluggable module to integrate situations into various existing RecSys. Since users' perception of situations and situations' impact on preferences are both personalized, SARE includes a Personalized Situation Fusion (PSF) and a User-Conditioned Preference Encoder (UCPE) to model the perception and impact of situations, respectively. We conduct experiments of applying SARE on seven backbones in various settings on two real-world datasets. Experimental results indicate that SARE improves the recommendation performances significantly compared with backbones and SOTA situation-aware baselines.Comment: Accepted at the International Conference on Database Systems for Advanced Applications (DASFAA 2024

    Unbiased Delayed Feedback Label Correction for Conversion Rate Prediction

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    Conversion rate prediction is critical to many online applications such as digital display advertising. To capture dynamic data distribution, industrial systems often require retraining models on recent data daily or weekly. However, the delay of conversion behavior usually leads to incorrect labeling, which is called delayed feedback problem. Existing work may fail to introduce the correct information about false negative samples due to data sparsity and dynamic data distribution. To directly introduce the correct feedback label information, we propose an Unbiased delayed feedback Label Correction framework (ULC), which uses an auxiliary model to correct labels for observed negative feedback samples. Firstly, we theoretically prove that the label-corrected loss is an unbiased estimate of the oracle loss using true labels. Then, as there are no ready training data for label correction, counterfactual labeling is used to construct artificial training data. Furthermore, since counterfactual labeling utilizes only partial training data, we design an embedding-based alternative training method to enhance performance. Comparative experiments on both public and private datasets and detailed analyses show that our proposed approach effectively alleviates the delayed feedback problem and consistently outperforms the previous state-of-the-art methods.Comment: accepted by KDD 202

    Wearable obstacle avoidance electronic travel aids for blind and visually impaired individuals : a systematic review

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    Background Wearable obstacle avoidance electronic travel aids (ETAs) have been developed to assist the safe displacement of blind and visually impaired individuals (BVIs) in indoor/outdoor spaces. This systematic review aimed to understand the strengths and weaknesses of existing ETAs in terms of hardware functionality, cost, and user experience. These elements may influence the usability of the ETAs and are valuable in guiding the development of superior ETAs in the future. Methods Formally published studies designing and developing the wearable obstacle avoidance ETAs were searched for from six databases from their inception to April 2023. The PRISMA 2020 and APISSER guidelines were followed. Results Eighty-nine studies were included for analysis, 41 of which were judged to be of moderate to high quality. Most wearable obstacle avoidance ETAs mainly depend on camera- and ultrasonic-based techniques to achieve perception of the environment. Acoustic feedback was the most common human-computer feedback form used by the ETAs. According to user experience, the efficacy and safety of the device was usually their primary concern. Conclusions Although many conceptualised ETAs have been designed to facilitate BVIs' independent navigation, most of these devices suffer from shortcomings. This is due to the nature and limitations of the various processors, environment detection techniques and human-computer feedback those ETAs are equipped with. Integrating multiple techniques and hardware into one ETA is a way to improve performance, but there is still a need to address the discomfort of wearing the device and the high-cost. Developing an applicable systematic review guideline along with a credible quality assessment tool for these types of studies is also required. © 2013 IEEE
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