Subjects: Geosciences >> Geography submitted time 2024-03-01 Cooperative journals: 《干旱区研究》
Abstract： This study utilized observational data on floating dust days from multiple stations across the TarimBasin spanning 2011 to 2020. In total, 396 days characterized by persistent floating dust were selected.Employing ERA5 meteorological reanalysis data, the PCT algorithm was used to objectively classify near-surfaceand upper- layer circulation patterns associated with persistent floating dust in the Tarim Basin. Furthermore,typical synoptic processes accompanying persistent floating dust were selected for analysis. The aim was toelucidate the relationship between persistent floating dust and synoptic circulation at different altitudes. Thefindings revealed three distinct near-surface weather patterns during persistent floating dust days: high-pressurefront, high- pressure bottom, and uniform pressure field. Variations in meteorological conditions and pollutantconcentrations were evident among these surface weather patterns. The near- surface weather system evolvedfrom the high-pressure front to high-pressure bottom, culminating in the uniform pressure field. The upper-layerweather system alternated between the westerly trough type and the high-pressure ridge-zonal latitudinal type. Asthe Siberian cold high-pressure system moved eastward and southward, upper-layer circulations were influencedby the westerly trough and the Iranian high- pressure system. Persistent floating dust events occurred anddeveloped alongside elevated near- surface PM10 concentrations. These events concluded when a near- surfaceuniform pressure field prevailed, marked by limited air pressure system activity and an upper- layer circulationcharacterized by the zonal latitudinal pattern.
Subjects: Medicine, Pharmacy >> Preventive Medicine and Hygienics submitted time 2024-02-19 Cooperative journals: 《中国全科医学》
Abstract： Although medicine is developing rapidly，many chronic diseases are still extremely challenging to manage and control at the moment. In China，the prevalence rates of hypertension are still on the rise，making early identification，therapy，and prevention of the condition crucial. Digital therapy makes use of the Internet to assist patients with hypertension in strengthening their understanding of hypertension，encouraging the proper administration of hypertension medication，and improving their ability to manage their own health. This paper aims to provide an overview of the current state of digital therapy application in the medical field，investigate the viability and suitability of these therapies for the treatment of hypertension，and anticipate the advancement of digital therapy-based hypertension management and treatment in the future. Future developments in digital therapy involve bringing together the knowledge of Chinese medicine health management，optimizing the benefits of digitizing both Chinese and Western medicine for the diagnosis and treatment of hypertension，forming a professional team for digital therapy，safeguarding patient privacy and data security，and offering patients more convenient，effective，and secure preventive and treatment options.
Subjects: Geosciences >> Geology submitted time 2023-08-23 Cooperative journals: 《中国科学院院刊》
Abstract： In order to implement the spirit of General Secretary Xi Jinping’s important speech on strengthening the comprehensive control of desertification and promoting key ecological engineering projects such as the “Three-North Shelterbelt Program”, this study is designated to make concrete efforts to win the battle against desertification on the edge of Hexi Corridor–Taklimakan Desert. The study deeply explores the situation of wind-blown sand flux and prevention tasks in the area. Based on the characteristics of desertified land and wind-blown sand activities on the edge of Hexi Corridor–Taklimakan Desert, the goal is set to effectively prevent the spread of sand and control dust sources. The core focus is on wind prevention, sand resistance, and dust control. The strategic thinking has been formulated for the counterattack battle on the edge of Hexi Corridor–Taklimakan Desert. By systematically analyzing the source areas and paths of “wind, sand, and dust” and targeting the key zones of the desert edge and areas requiring prevention, the key areas and tasks are proposed for desertification control on the edge of the Hexi Corridor–Taklimakan Desert, so as to provide scientific and technological support for winning the battle against desertification on the edge of Hexi Corridor–Taklimakan Desert.
Subjects: Statistics >> Social Statistics submitted time 2023-08-12 Cooperative journals: 《中国科学院院刊》
Abstract： In order to implement the spirit of General Secretary Xi Jinping’s important speech on strengthening the comprehensive control of desertification and promoting key ecological engineering projects such as the “Three-North Shelterbelt Program”, this study is designated to make concrete efforts to win the battle against desertification on the edge of Hexi Corridor–Taklimakan Desert. The study deeply explores the situation of wind-blown sand flux and prevention tasks in the area. Based on the characteristics of desertified land and wind-blown sand activities on the edge of Hexi Corridor–Taklimakan Desert, the goal is set to effectively prevent the spread of sand and control dust sources. The core focus is on wind prevention, sand resistance, and dust control. The strategic thinking has been formulated for the counterattack battle on the edge of Hexi Corridor–Taklimakan Desert. By systematically analyzing the source areas and paths of “wind, sand, and dust” and targeting the key zones of the desert edge and areas requiring prevention, the key areas and tasks are proposed for desertification control on the edge of the Hexi Corridor–Taklimakan Desert, so as to provide scientific and technological support for winning the battle against desertification on the edge of Hexi Corridor–Taklimakan Desert.
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2020-11-20 Cooperative journals: 《干旱区地理》
Abstract：利用乌鲁木齐市城区和郊区的5座100 m气象铁塔10层比湿数据和乌鲁木齐气象站L波段探空雷达资料，详细分析了边界层2 km内比湿廓线特征，城区和郊区近地层比湿季节变化和日变化特征，揭示了乌鲁木齐逆湿的原因，得出以下结果：（1）乌鲁木齐市比湿季节差异明显，冬季最小，春季、秋季稍大，夏季最大，夏季比湿约为冬季的4～5倍，但秋季仅比春季大1 g·kg－1。除冬季外，比湿均随高度增加而趋于减小，夏季减小最显著，冬季比湿的垂直变化很小。比湿廓线极小值白天和夜间出现高度相近，且有多个极小值。夏季和冬季比湿日变化最大，且位相相反；夏季夜间大、白天小，冬季与之相反。冬季，郊区比湿小于城区；其余季节城、郊比湿差异不明显。（2）2 km内存在逆湿现象，逆湿出现概率高于35%，概率1月最大、7月最小。1月逆湿最大高度超过1 500 m，7月逆湿最大高度可达到1 900 m，且最大厚度可达到1 550 m。逆湿强度最大在7月和10月可达2. 5 g·kg－1·（100 m）-1，而1月最小。（3）1月逆湿往往与逆温相伴随，逆温层改变了水汽的垂直分布结构，从脱地逆温层顶起出现逆湿现象，逆湿还与水汽输送有关。本研究可以有效地揭示空气湿度的季节特征，为研究城市大气污染形成的气象因素提供了一个思路。
Subjects: Geosciences >> Geography submitted time 2020-01-06 Cooperative journals: 《干旱区地理》
Abstract：利用塔克拉玛干沙漠22个气象站（周边21个站和沙漠腹地1个塔中站）2005—2007年的逐时风记录数据，首先基于输沙势定义计算了2007年各测站的16个方位的输沙势；其次以内积相似度指数聚类分析为基础，再结合其空间分布特点，把该沙漠的动力输沙环境划分为5种类型：沙漠东部库尔勒型（西西南型）、北部新和型（偏南型）、西部策勒型（偏东型）、南部民丰型（东东北型）和一种特殊类型；其中策勒型输沙势最大、新和型最小；民丰型输沙势方向稳定性最好、库尔勒型最差；此外，输沙势的季节差异上（2007年为例），各测站春夏季（3~8月）的输沙势都很强，占年均输沙势的81.29%~98.79%，尤其是5月份占年输沙势的22.7%~56.8%，冬季（11月~次年2月）几乎无起沙风；沙漠合成输沙势年际变化表现为：输沙势变幅为±33%，输沙方向变幅为±9.6°，其中输沙势值变幅最大是阿拉尔站（±80%），方向变幅最大的是库车站（±24.4°）。
Subjects: Geosciences >> Geography submitted time 2019-11-15 Cooperative journals: 《干旱区地理》
Abstract：利用乌鲁木齐市5座100 m气象塔10层气温观测资料，通过统计方法详细分析了乌鲁木齐市城区和郊区近地层不同高度气温季节变化和日变化特征。研究表明：乌鲁木齐市四季均存在逆温，北郊逆温最明显。近地层100 m内主城区气温日较差较小，约为3.5～5.5 ℃；郊区气温日较差较大，约为4.2～7.0 ℃。夏季郊区气温高于城区，冬季北郊气温最低、南郊最高；白天大气基本上为超绝热不稳定状态，夜间城区气温高于郊区。春、秋季，白天城区和郊区温差小、夜间大，且愈近地面温差愈大；春季城区与南郊温差可达2.4 ℃、秋季可达3 ℃。城区和郊区各季节各层最高气温与最低气温出现时间几乎不同步达到。夏季、秋季、冬季和春季最高气温分别约在17:00～18:10、16:00～17:20、14:30～15:50（北郊滞后1.5 h）、17:00～18:00（南郊提前1.5 h）出现，最低气温分别约在7:10～8:20、8:00～9:00、冬季为多个时段（这与出现逆温有关）、7:30～8:40出现。
Subjects: Geosciences >> Other Disciplines of Geosciences submitted time 2019-09-11 Cooperative journals: 《干旱区研究》
Abstract：利用塔克拉玛干沙漠腹地-塔中地区的风速、风向观测资料，分析晴天、沙尘暴和扬沙天气条件下不同高度平均风速、风速脉动和风向脉动特征，探讨沙尘天气对近地层风速和风向脉动的影响。结果表明：① 3种天气条件下，地表0.5 m以上各高度层的脉动风速具有较好的相关性，且相邻高度脉动风速的相关性更加显著，相关系数均大于0.68；脉动风速的波动范围与高度呈正比例关系。② 随着高度的增加，沙尘暴和扬沙天气条件下的风速脉动强度呈增大趋势，而晴天时则是先增大后减小；风速脉动强度在沙尘暴天气时最大，扬沙天气次之，晴天最小；不同天气条件下2 m高度范围内风速脉动强度的增长速度大于2~10 m高度。③ 不同天气条件下风向脉动幅度均较小，且基本不随高度的改变而变化。
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2019-06-13 Cooperative journals: 《干旱区地理》
Abstract：利用乌鲁木齐市4座10层100 m梯度气象塔2013年6月~2014年4月气象观测资料和7个环境监测站[WTBX]AQI[WTBZ]资料，计算并分析了大气混合层厚度和稳定度特征，探讨了大气混合层厚度和稳定度与污染的关系。结果表明：乌鲁木齐市混合层厚度夏季郊区高、城区低，冬季从南郊—城区—北郊随地势降低依次降低；夏季和冬季分别在1 559～1 772 m和526～1 156 m之间。地面至2 km以上每500 m高度间隔统计混合层厚度，500～1 000 m出现频率最多；月变化为6～9月基本在500 m以上，且每个高度区间其概率均超过10%，10月～次年2月1 500 m以上区间概率明显减小；日变化为中午13:00～16:00达到最高值，下午和傍晚迅速下降。白天较大的感热输送提供充足的热力条件，这也体现出白天以不稳定层结为主，夜间则以稳定层结为主。大气稳定度分类结果，夏季郊区和城区不稳定（A～C类）所占比例差不多，冬季北郊稳定（E、F类）所占比较最大、城区最弱。[WTBX]AQI指数冬季最大，从南郊—城区—北郊依次增大，这与采暖期污染物多、南郊比北郊地势高有利于扩散输送有关。总体来看，乌鲁木齐大气混合层厚度空间分布与气象要素、大气稳定度、地形等密切相关，对AQI[WTBZ]指数分布有重要影响，这对近地层大气污染状况预报有着重要的指导意义。
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2018-06-10 Cooperative journals: 《干旱区研究》
Abstract： 利用塔克拉玛干沙漠北缘肖塘陆气相互作用观测站2014年7月12月的陆面通量数据，通过最小二乘法（OLS）和能量平衡比率法（EBR）研究该地区能量平衡闭合特征。结果表明：能量通量各分量均呈倒U形单峰变化趋势，除潜热通量外，均有明显的季节变化特征，表现为：夏季＞秋季＞冬季。能量平衡闭合程度：全天＞白天＞夜间，且具有逐月递减的变化趋势。地表以下5cm处土壤热通量下的能量闭合程度明显高于地表土壤热通量下的能量闭合程度。能量闭合率在日出日落时段波动剧烈，夜间为负，且下午明显高于上午。不同天气下的能量闭合程度表现为：晴天＞阴天＞沙尘暴＞降雨。
Subjects: Computer Science >> Computer Application Technology submitted time 2016-05-03
Abstract：近年来，迁移学习已经引起了广泛的关注。迁移学习是运用已存有的知识对不同但相关领域问题进行求解的新的一种机器学习方法。传统机器学习基于两个基本假设：(1) 用于学习的训练样本与新的测试样本满足独立同分布的条件；(2) 必须有足够可利用的训练样本才能学习得到一个好的分类模型。迁移学习降低了要求，目的是迁移已有的知识来解决目标领域中仅有少量或没有有标签样本数据时的学习问题。本文对迁移学习算法以及相关理论研究进展进行了综述，并介绍了我们在该领域所做的研究工作，特别是利用生成模型在概念层面建立迁移学习模型。最后指出了迁移学习下一步可能的研究方向。
Peer Review Status:
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