ID 原文 译文
25055 随着人们对卫星导航系统定位精度需求的不断提升，近年来伪距偏差问题越来越受到广泛关注。 With the increasing demands for higher positioning precision of global satellite navigation systems, pseud-orange biases have been receiving more and more attentions in recent years．
25056 然而截至目前，国内外专家学者对北斗系统的伪距偏差问题研究甚少。 Unfortunately, few researches have been done on the pseudorange biases of Beidou navigation satellite system (BDS)．
25057 本文首先深入分析了北斗系统的伪距偏差产生根源，在此基础上对伪距偏差随接收机参数设置变化的关系进行详细阐述。 The origin of BDS pseudorange biases are illustrated thoroughly in the beginning, and then based on which the dependency of biases on receiver configurations are studied．
25058 然后基于昊平观测站的 40m 大口径天线采集的各颗北斗卫星下行信号数据，利用软件接收机遍历并分析了在不同接收机带宽、不同相关器间隔情况下，以及不同卫星仰角情况下北斗各颗卫星的 B1I 和 B3I 信号伪距偏差测量结果。 Our research used high-fidelity BDS satellite signal observations collected by a 40m high-gain dish antenna in Haoping Observatory, and used software receiver technology to achieve the pseudorange biases results of BDS B1I and B3I signals from different front-end bandwidths, different correlator spacings and different satellite elevations．
25059 最后根据北斗伪距偏差的特点，首次给出了我国北斗接收机参数设置建议。 Finally, based on the characteristics of BDS pseudorange biases, the suggested settings of BDS receiver configurations such as front-end bandwidth and correlator spacing are clearly proposed for the first time．
25060 研究结果表明:在一定的接收机参数设置范围内，本文提出的方法可以将北斗伪距偏差降低到 20cm 以内。 Research results show that the pseudorange biases of BDS signals will be less than approximately 20 cm under the condition proposed in this paper．
25061 本文的研究成果不仅能够进一步促进广大专家学者对我国北斗伪距偏差的深入了解及广泛关注，同时还能促进我国 BDS (BeiDou Navigation Satellite System)及其他 GNSS(Global Navigation Satellite System)系统接口控制文件的进一步完善。 This study will contribute to a better understanding of and special attention to pseudorange biases, and will be a significant promotion to a clear definition of the appropriate receiver parameter settings in the ICDs for BDS and other individual satellite system．
25062 针对交通推荐服务中推荐的出行方式单一、忽略用户出行偏好以及多分类任务中样本类别不平衡等问题，本文提出一种基于粒子群优化和 LightGBM 的情景感知多式联运推荐方法。 In order to solve the problems of considering only one transportation mode and neglecting user preferencein transportation recommendation problem, and class imbalance problem in multi-class task, a context-aware multi-modal transportation recommendation method based on particle swarm optimization and LightGBM is proposed．
25063 该方法综合考虑用户在时间、空间以及出行成本上的出行偏好，利用数理统计和表示学习方法捕捉用户出行与各要素之间的内在关系。 This method comprehensively considers the user's travel preferences in terms of time, space and travel cost, and uses mathematical statistics and representation learning methods to capture the internal relationship between user travel and various elements．
25064 同时，为了缓解样本类别不平衡带来的负面影响，利用基于粒子群优化算法的指标优化方法为每个类别搜索最优权重，对模型的预测结果进行修正，以实现最大化评价指标的目的。 At the same time, in order to alleviate the negative impact caused by the imbalance of sample class, the index optimization method basedon particle swarm optimization algorithm is used to search for the optimal weight for each class, and the prediction results ofthe model are modified to achieve the purpose of maximizing the evaluation index．