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1. chinaXiv:202204.00119 [pdf]

Xitunaspis, a new eugaleaspid fish (Eugaleaspiformes, Galeaspida) from the Lower Devonian of Qujing, Yunnan

SUN Hao-Ran; GAI Zhi-Kun; CAI Jia-Chen; LI Qiang; ZHU Min; ZHAO Wen-Jin
Subjects: Biology >> Zoology

A new genus and species of the family Eugaleaspidae (Eugaleaspiformes, Galeaspida), Xitunaspis magnus gen. et sp. nov., is described from the Lower Devonian Xitun Formation in Qujing, Yunnan Province, China. The new genus displays the diagnostic characters of the Eugaleaspidae, including a slit-like median dorsal opening, no inner cornual process, developed median dorsal canals, and only three pairs of lateral transverse canals extending from lateral dorsal canals. Different from the other eugaleaspids, X. magnus possesses a large headshield with thick dermal bone and a more plesiomorphic sensory canal system. The phylogenetic analysis of the Galeaspida reveals that Xitunaspis clusters with Dunyu and Eugaleaspis to form a monophyletic clade Eugaleaspidae Liu, 1965, and has a closer relationship with Dunyu than Eugaleaspis by sharing the thick dermal bone of the headshield. The new finding represents the first convincing fossil record of the Eugaleaspiformes in the middle Lochkovian Xitun Formation and adds to our knowledge about the morphology of eugaleaspiforms and the evolutionary pattern of the sensory canal system in the Eugaleaspiformes and even Galeaspida.

submitted time 2022-04-16 Cooperative journals:《古脊椎动物学报》 Hits1945Downloads255 Comment 0

2. chinaXiv:202204.00120 [pdf]

New fossils of small and medium-sized bovids from the Early Pleistocene Site of Shanshenmiaozui in Nihewan Basin, North China

TONG Hao-Wen; ZHANG Bei; CHEN Xi; WANG Xiao-Min
Subjects: Biology >> Zoology

Shanshenmiaozui site in Nihewan Basin in North China is a recently discovered Early Pleistocene site which yields rich and diverse mammalian fossils. In the fauna, the small and medium-sized bovid fossils are well represented and can be referred to the following taxa: Spirocerus wongi, Gazella sinensis, Ovis shantungensis and Megalovis piveteaui respectively, among which G. sinensis is the dominate species. S. wongi and G. sinensis are mainly represented by horn-cores and partial skull bones as well as mandibles; in addition, metacarpal and/or metatarsal bones were also recognized for all of the four species. The horn-cores are easy to be identified to the species level, while the dentitions and the postcranial bones underwent a series of examinations and comparisons before getting properly determined and referred to the most approximate taxa. Among the postcranial bones, the metapodials, especially to the metacarpal bones special attentions were paid, which are crucial not only for taxonomic identification, but also for phylogenetic and paleoecological reconstructions; the previously misidentified metapodial specimens in Nihewan fauna were reconsidered in this paper. In the SSMZ fauna, the bovid guild is dominated by Gazella and Bison, which indicates steppe was the most important biome in Nihewan Basin during Early Pleistocene.

submitted time 2022-04-16 Cooperative journals:《古脊椎动物学报》 Hits1792Downloads222 Comment 0

3. chinaXiv:202204.00121 [pdf]

Attributing “Gomphotherium shensiense” to Platybelodon tongxinensis, and a new species of Platybelodon from the latest Middle Miocene

WANG Shi-Qi; LI Chun-Xiao
Subjects: Biology >> Zoology

Platybelodon is the predominant proboscidean of northern China’s Middle Miocene. However, the cranial and cheek tooth morphologies are not clearly diagnosed. In particular, the differential diagnoses between Platybelodon and Gomphotherium have not been comprehensively examined. Here we restudied the cranium previously identified as Gomphotherium shensiense. The upper tusks lack an enamel band, the rostrum is long and narrow, the facial part is rostrally positioned, and a large “prenasal slope” is present. These characters are distinct from those of any species of Gomphotherium, but fit well with some primitive species of Platybelodon, i.e., P. tongxinensis and P. danovi. The molars are also close to the type specimen of P. tongxinensis in the tetralophodont M3 with mesiodistally wide interlophs, curved outline, and a tendency of cementodonty. In this article, we synonymized Gomphotherium shensiense with P. tongxinensis. Moreover, we recognized a new species, Platybelodon tetralophus, from the P. grangeri material collected by the AMHN expedition in Tunggur region. Platybelodon tetralophus differs from P. grangeri and the other species in the tetralophodont M2 and m2, representing the most derived species within Platybelodon. It has only occurred in the uppermost horizon of the Tunggur Formation, i.e., the Tamuqin Fauna (Platybelodon Quarry and Wolf Camp Quarry of AMHN). This work is a comprehensive amending of the genus Platybelodon.

submitted time 2022-04-16 Cooperative journals:《古脊椎动物学报》 Hits1591Downloads191 Comment 0

4. chinaXiv:202204.00123 [pdf]

新疆县域人力资源时空差异及影响因素分析

孙继明
Subjects: Geosciences >> Geography

基于第五和第六次全国人口普查数据,运用区域人力资源测算方法、多元线性回归、地理探测器研究方法,分析了新疆县域人力资源时空分布差异及影响因素。结果表明:(12000—2010新疆人力资源总量增加 54.89%,具有分散分布、空间差异增大的特征;人均人力资源水平提升 30.71%,地域差异主要体现为南、北疆差异,呈低值集聚-高值分散的特点。(2)剔除人力资源教育投入的积累性,2000—2010年新疆人力资源总量增加的县(市、区)主要集中在南疆,北疆、东疆以 减少为主,人均人力资源提升程度南疆明显高于北疆、东疆。(3)新疆人均人力资源时空分布差异受多种因素的综合影响,除教育因素外,二三产业从业人员,人均国民生产总值(GDP)、地方财政收入及从事卫生、社会保障人数因子的驱动较为显著。本研究结果可为新时期缩小新疆区域人力资 源发展差异提供参考。

submitted time 2022-04-16 Cooperative journals:《干旱区地理》 Hits2188Downloads153 Comment 0

5. chinaXiv:202204.00117 [pdf]

提高YFOSC光谱观测效率方法的研究

陈宇扬; 王传军; 范玉峰; 伦宝利
Subjects: Astronomy >> Astrophysical processes

丽江2.4米望远镜作为目前国内最大口径的通用型光学望远镜,在我国的夜天文观测领域有着十分重要的地位。从近几年观测时间分配的整体情况来看,云南暗弱天体成像光谱仪(YFOSC)的光谱观测在丽江2.4米望远镜总观测时间中的占比是最多的,因此提高其光谱观测效率和数据质量就成为了保证望远镜稳定科学产出的关键因素。本文将从影响YFOSC光谱观测效率的两个重要因素——星像入狭缝和望远镜闭环跟踪出发,对提高丽江2.4米望远镜YFOSC光谱观测效率和质量的方法进行介绍。

submitted time 2022-04-15 Cooperative journals:《天文研究与技术》 Hits1764Downloads86 Comment 0

6. chinaXiv:202204.00115 [pdf]

RFI抑制技术在射电天文中的应用

张海龙; 张亚州; 王杰; 冶鑫晨; 王万琼; 李嘉; 张萌; 杜旭
Subjects: Astronomy >> Astrophysical processes

针对射电天文观测过程中的射频干扰(RFI)问题,详细分析了国内外台站RFI抑制策略。根据各天文台站实际观测过程中遇到的RFI问题,分别从主动预防阶段、预相关阶段、后相关阶段、机器学习和深度学习等方面研究了RFI的预防策略和抑制方法。详细分析了主动预防阶段可采取的方法,预相关阶段的自适应滤波,和空间滤波方法;后相关阶段的VarThreshold,SumThreshold和奇异值分解等方法。探讨了基于机器学习的主成分分析、支持向量机、全卷积神经网络、卷积神经网络、U-Net等相关技术和方法在RFI信号处理方面的应用。

submitted time 2022-04-14 Cooperative journals:《天文研究与技术》 Hits1677Downloads104 Comment 0

7. chinaXiv:202204.00100 [pdf]

哈萨克斯坦北部小麦遥感估产方法研究

尹瀚民
Subjects: Geosciences >> Geography

以哈萨克斯坦北部雨养耕作区为研究靶区,基于春小麦产量统计数据和遥感光谱指数,开 展了春小麦估产最优预测时期及植被指数分析,采用回归分析、随机森林、支持向量机及双向循环 神经网络模型估算春小麦产量,并对比分析了不同模型的模拟精度。结果表明:北哈萨克斯坦州、 阿克莫拉州和库斯塔纳州2007—2016年春小麦估产的最佳预测时期为626日—85日,该时期是春小麦产量形成的关键时期。北哈萨克斯坦州春小麦估产最优植被指数为712日的绿度叶绿素指数(Green chlorophyll index, CIgreen),阿克莫拉州春小麦估产最优植被指数为85日的绿度动态宽波段指数(Green wide dynamic range vegetation index, WDRVIgreen),库斯塔纳州春小麦最优估产植被指数为712WDRVIgreen。对比分析4种模型模拟春小麦产量的精度,在样本点较少的情况下,双向循环神经网络模型相比其他模型在估算哈萨克斯坦北部三州春小麦产量上精度较高;春小麦产量与植被净初级生产力NPP相关性分析结果显示,北哈萨克斯坦州、阿克莫拉州和库斯塔纳州决定系数R20.50以上面积占比分别为44%94%77%,表明上述估产模型可应用于哈萨克斯坦北部三州春小麦估产,尤其是阿克莫拉州和库斯塔纳州。

submitted time 2022-04-14 Cooperative journals:《干旱区地理》 Hits2414Downloads62 Comment 0

8. chinaXiv:202203.00083 [pdf]

体型知觉的准确性及其认知机制

刘爽爽; 肖斌; 王葵; 陈楚侨
Subjects: Psychology >> Social Psychology

体型知觉的准确性既和一般人群的心理健康水平有关,又对进食障碍的理解、预防和治疗具有重要意义。首先,进食障碍患者可能高估自己的身体,其体型知觉准确度可能受其BMI和症状的影响,并与患者预后相关。其次,通过和对他人体型估计的结果进行对比发现,对自己的体型的高估可能受到对自己身体态度因素的影响。第三,一般人群对自己的体型估计的结果往往不一致,这可能是体型知觉的不同量化方式所致。最后,体型知觉准确性的相关认知机制主要有收缩偏差、视觉适应和序列依赖效应。

submitted time 2022-03-25 Hits499Downloads254 Comment 0

9. chinaXiv:202203.00076 [pdf]

Adjustment of precipitation measurements using Total Rain weighing Sensor (TRwS) gauges in the cryospheric hydrometeorology observation (CHOICE) system of the Qilian Mountains, Northwest China

ZHAO Yanni; CHEN Rensheng; HAN Chuntan; WANG Lei
Subjects: Geosciences >> Hydrology

Abstract: Precipitation is one of the most important indicators of climate data, but there are many errors in precipitation measurements due to the influence of climatic conditions, especially those of solid precipitation in alpine mountains and at high latitude areas. The measured amount of precipitation in those areas is frequently less than the actual amount of precipitation. To understand the impact of climatic conditions on precipitation measurements in the mountainous areas of Northwest China and the applicability of different gauges in alpine mountains, we established a cryospheric hydrometeorology observation (CHOICE) system in 2008 in the Qilian Mountains, which consists of six automated observation stations located between 2960 and 4800 m a.s.l. Total Rain weighing Sensor (TRwS) gauges tested in the World Meteorological Organization-Solid Precipitation Intercomparison Experiment (WMO-SPICE) were used at observation stations with the CHOICE system. To study the influence of climatic conditions on different types of precipitation measured by the TRwS gauges, we conducted an intercomparison experiment of precipitation at Hulu-1 station that was one of the stations in the CHOICE system. Moreover, we tested the application of transfer functions recommended by the WMO-SPICE at this station using the measurement data from a TRwS gauge from August 2016 to December 2020 and computed new coefficients for the same transfer functions that were more appropriate for the dataset from Hulu-1 station. The new coefficients were used to correct the precipitation measurements of other stations in the CHOICE system. Results showed that the new parameters fitted to the local dataset had better correction results than the original parameters. The environmental conditions of Hulu-1 station were very different from those of observation stations that provided datasets to create the transfer functions. Thus, root-mean-square error (RMSE) of solid and mixed precipitation corrected by the original parameters increased significantly by the averages of 0.135 (353%) and 0.072 mm (111%), respectively. RMSE values of liquid, solid and mixed precipitation measurements corrected by the new parameters decreased by 6%, 20% and 13%, respectively. In addition, the new parameters were suitable for correcting precipitation at other five stations in the CHOICE system. The relative precipitation (RP) increment of different types of precipitation increased with rising altitude. The average RP increment value of snowfall at six stations was the highest, reaching 7%, while that of rainfall was the lowest, covering 3%. Our results confirmed that the new parameters could be used to correct precipitation measurements of the CHOICE system.

submitted time 2022-03-24 Cooperative journals:《Journal of Arid Land》 Hits1765Downloads213 Comment 0

10. chinaXiv:202203.00065 [pdf]

身体姿势表情测试集在中国成人和儿童中的评定

Yang, Yunmei ; HOU, Wenwen ; Li, Jing
Subjects: Psychology >> Developmental Psychology

目的:身体姿势表情刺激集为情绪研究提供了一套标准化的刺激材料,该刺激集在西方成人的一致性已经得到了验证,但是该刺激集在中国人群中的一致性尚不清楚。因此本研究从原始的254张图片中选取了快乐、悲伤、恐惧和愤怒各42张图片来验证该刺激集在中国人群中的适用性。
方法:31名中国大学生和41名中国学龄前儿童参加了这项研究。所有被试都被要求完成情绪识别和判断任务。
结果:结果表明,成人的评定一致性较高,而儿童的一致性处于中等水平。对于成人来说,悲伤最容易识别,其次是恐惧,愤怒和幸福最难识别。对于儿童来说,恐惧最容易识别,愤怒和悲伤次之,快乐最难识别。与此同时,成人对快乐和悲伤的准确率高于儿童。对于成人来说,他们更容易将积极的情绪与消极情绪混淆。他们倾向于将悲伤、恐惧和愤怒误认为是快乐。对于儿童来说,他们更容易将悲伤识别为恐惧和快乐。他们也容易将愤怒识别为恐惧。
局限:恐惧和愤怒情绪图片适用于5岁的儿童,而悲伤和快乐情绪,尤其是快乐情绪图片的适用性并不理想。在未来可以通过结合中国人的实际生活重新拍摄传达快乐和悲伤情绪的身体姿势图片,并且可以选择年龄更小的孩子探查改良后的图片适用性。
结论:这些结果表明,中国和西方成人对身体姿势表情刺激集的识别模式大致相同。但是,在相同的文化背景下,成人和儿童的识别模式差异很大,并且成人的识别准确率高于儿童。

submitted time 2022-03-19 Hits2383Downloads306 Comment 0

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