Subjects: Geosciences >> Geography submitted time 2021-12-12 Cooperative journals: 《干旱区研究》
Abstract：巴里坤湖是天山东部山间内陆封闭型湖泊，了解巴里坤湖的演变特征对于开展湖泊保护与生态环境治理具有重要意义。利用308景Landsat系列和Sentinel 2遥感影像提取1995—2020年湖泊水面的时间序列，并结合巴里坤气象站资料以及从遥感影像上提取的耕地面积数据，分析湖泊在气候变化与人类活动影响下的变化趋势。结果表明：湖泊变化经历了2个阶段：1995—2006年萎缩，从年均值57.33 km2下降到35.53 km2，下降速率1.98 km2·a-1，萎缩35.79%；2006—2020年扩张，从年均值35.53 km2上升到46.59 km2，上升速率0.79 km2·a-1，扩张31.12%。多年湖泊面积的月变化统计表明：湖泊在5月达到最大值（73.09±21.01）km2，11月达到最小值（43.90±16.97）km2。影响因素：1995—2006年，降水变化幅度较小，农业用水与蒸发量增加是巴里坤湖萎缩的主要原因；2006年后，巴里坤县出台多种湿地保护措施，耕地面积扩张趋势得到控制，降水显著增加与蒸发量减少成为湖泊面积扩张的主要原因。
Subjects: Traffic and Transportation Engineering >> Railway Transportation submitted time 2024-02-07 Cooperative journals: 《应用力学学报》
Abstract：
A three-dimensional transient contact finite element model based on explicit time integration is developed for the rack railway suitable for mountain rail transit.The medium and high frequency coupling dynamic interaction between gear-rack meshing and wheel-rail rolling contact can be analyzed in time domain.Factors such as the true geometry of the wheelset and track,the ‘wheel paradox’ caused by the diameter difference between the gear and the wheel,and structural vibration are taken into account.The gear and rack meshing and wheel-rail contact are both solved by a surface-to-surface contact algorithm with the Coulomb friction integrated.Considering the zero and non-zero wheel-rail friction coefficients,the influence of the ‘wheel paradox’ on the gear-rack meshing and wheel-rail rolling contact can be deconstructed.Taking the Strub rack railway as an example,the dynamic contact phenomena under a running speed of 10 km/h and slopes of 0‰,240‰ and 480‰ are investigated.The results show that the contact forces of gear-rack and wheel-rail show periodic fluctuations due to gear meshing,but the vertical total force and total traction torque fluctuate near gravity load and traction torque,respectively.The wheel paradox makes the vertical contact force and normal stress of the rack decrease,while the vertical contact force and normal stress of the wheel-rail increase.In terms of the tangential contact solution,the tangential contact stress of the tooth surface and the slip area in the contact spot increase.Under the condition of slope 240‰,the wheel-rail friction coefficient increases from 0 to 0.2,the maximum normal contact stress of rack and wheel-rail increases from 248.69 and 752.66 MPa to 195.17 and 757.44 MPa,and the maximum tangential contact stress changes from 24.48 and 152.84 MPa to 21.31 and 2.14 MPa.The wheel-rail contact presents full sliding contact due to significant creep.Under the same speed and friction conditions,the increase of slope makes the vertical force and traction force of rack increase,the vertical force and traction force of wheel and rail decrease,and the contact stress has the same change.
Subjects: Digital Publishing >> New Media submitted time 2023-10-08 Cooperative journals: 《中国传媒科技》
Abstract：第五媒介在为融媒体思政工作提供一系列技术条件的同时,其在传播模式、受众地位、内容形式、语言形态上引发的巨大变革,也对融媒体思政工作提出了挑战。社交式思政,通过一系列自身建设,将上述变革吸纳、融入自身范式特征中,能有效促成融媒体思政达成使命。
Subjects: Library Science，Information Science >> Library Science submitted time 2023-10-08 Cooperative journals: 《知识管理论坛》
Abstract： The same to Chinese abstract. [Purpose/significance] The domestic research on linked data is still in its initial stage. With theoretical research and application research being immature, this study could provide some inspiration and references fordomestic research on linked data. [Method/process] By reviewing lots of literature and the systemic analysis, this study has analyzed the differences between domestic and international researches in terms ofthe quantity of published papers, research groups, word frequency and subject identification. [Result/conclusion] Based on the analysis above, this article proposes four tips to promote the development of domestic research on linked data, including indigenous research, paying more attention to application research, optimized the structure of research groups and focusing on multidisciplinary applications.
Subjects: Geosciences >> Hydrology submitted time 2022-08-08 Cooperative journals: 《干旱区地理》
Abstract：喀喇昆仑山分布有众多的跃动型冰川，跃动机理存在异质性。使用Landsat、Sentinel-1A、TSX/TDX等多源遥感数据，获取了中喀喇昆仑布拉尔杜冰川在跃动期间冰川表面高程和表面流速变化。结果表明：布拉尔杜冰川从2006年开始，流速逐渐增加；到2013年之后进入快速运动期，最高流速可达4.9 md-1；2015年8月底，冰川表面速度急剧下降，随后保持较低的流速至2016年1月，而后流速再次增加，到同年2月初便进入平静期。20002014年冰川主干中上游有明显隆起，而冰川接收区明显减薄，最大减薄达89 m；20142018年冰川主干中上游以及各支流均有不同程度的减薄，冰川主干的接收区高程显著增加，最大增厚120 m。根据冰川表面高程变化以及流速变化的特征，认为布拉尔杜冰川的支流引发了此次跃动，且本次跃动受水文机制的影响较大；结合现有的数据和文献，推断布拉尔杜冰川的跃动间隔约为40 a；为喀喇昆仑冰川跃动研究提供更多的实例，也可为此区域冰川灾害预警研究提供参考。
Subjects: Psychology >> Clinical and Counseling Psychology submitted time 2023-09-26
Abstract： The core feature of major depressive disorder, as defined in the DSM-5, is persistent emotional disturbances characterized by excessive sadness and drastically reduced pleasant emotional experiences. Recent research on emotion dynamics has emphasized that the emotion dysregulation in major depressive disorder goes beyond increased negative emotional intensity and decreased positive emotional intensity. It is also manifested as abnormal patterns of emotion dynamics. A total of 18 studies were included in this systematic review, which utilized ecological momentary assessment to explore everyday emotion dynamics in major depressive disorder. The key findings are as follows: (1) Patients with depression have greater negative emotion fluctuations compared with the healthy control group. These fluctuations were manifested as greater negative emotion variability and instability. (2) Depressed patients exhibit a rigid and inflexible emotional system, characterized by greater negative emotion inertia and denser emotion networks. (3) Depressed patients exhibit abnormalities in emotional reactivity. This is reflected as the mood brightening effect after positive events and greater negative emotion reactivity after negative events. (4) Patients with depression experience a decreased complexity in their emotional system. This is manifested as a lower level of emotion differentiation. Furthermore, patients with remitted depression also exhibit some degree of emotion dysregulation. This review is the first to comprehensively elucidate the primary features of emotion dysregulation in major depressive disorder from the perspective of emotion dynamics. These features provide potential intervention targets with high ecological validity for individualized treatment and relapse prevention of depression.
Subjects: Geosciences >> Space Physics submitted time 2017-01-22
Abstract： In order to analyze the radiative transfer characteristics of planetary atmosphere in the microwave and sub millimeter wave bands, the absorption coefficient of the gases included in planetary atmosphere are calculated by using line-by-line integration method. Based on the parameters of gas molecules in HITRAN database, such as the transition frequency, line strength and so on, the absorption feature of every gas molecule in the 1-3THz frequency range is simulated and compared with the existing atmospheric radiative transfer model of the Earth. As an example, the radiation transport characteristics of Earth’s and Mars’ atmosphere are analyzed and the brightness temperature of Earth’s atmosphere radiative transfer is simulated by using radiative transfer equation. The work in this article provides the model and theoretical basis for the selection of detection frequency band of planetary atmospheric composition and for the retrieval of atmosphere profiles.
Peer Review Status:
Awaiting Review
Subjects: Digital Publishing >> New Media submitted time 2023-10-08 Cooperative journals: 《中国传媒科技》
Abstract：【目的】伴随智媒融合和数字技术的深度发展，作为真人“数字孪生”的虚拟数字人不断更迭演进，对其媒介形象研究及建构问题是文章的主要目的。【方法】文章以虚拟人工智能、虚拟员工及虚拟偶像作为研究主体，结合本雅明、波德里亚等学者的相关理论，归纳总结智媒时代虚拟数字人的媒介形象特征，以作有关未来虚拟数字人媒介形象的建构路径创新探析。【结果】作为一种再临的“数字灵晕”和被消费的“文化符号”，未来虚拟数字人的媒介形象应从多元技术、多元风格、多元场景等维度进行建构，帮助虚拟数字人实现“在地化”传播。【结论】虚拟数字人的媒介形象研究及建构，一方面，能够在未来为人类畅游元宇宙提供可借鉴的虚拟形象参考；另一方面，能够借媒介形象建构之力促进人机耦合，助推人机传播。
Subjects: Digital Publishing >> New Media submitted time 2023-10-08 Cooperative journals: 《中国传媒科技》
Abstract：围绕 "建成具有强大引领力、传播力、影响力的国际一流新型主流媒体"目标,中央广播电视总台通过加速构建超清化、移动化、智能化的新一代技术体系来达到推动媒体融合向纵深发展的目的。本文阐述了近年来中央广播电视总台在4K/8K超高清、5G媒体传输、AI媒体应用等方面研究和应用的主要成果,结合"十四五"期间技术体系建设目标和任务的介绍,说明了中央广播电视总台在推动技术与内容深度融合方面的发展思路。
Subjects: Geosciences >> Geography submitted time 2023-04-07 Cooperative journals: 《干旱区地理》
Abstract： Soil wind erosion is the primary stage and important component of desertification in arid and semiarid regions. Evaluating its possibility and potential risk for wind erosion control at the regional level is of considerable importance. In recent years, remote sensing and geographic information technology are often combined with mathematical methods to build a risk assessment model. However, the current risk models of wind erosion are still lacking in mechanical parameters. This study was conducted in the Hetao Plain of China, which is a typical region of wind erosion and desertification. Soil hardness and shear strength were measured in the field to determine the difference in soil erodibility among different land use types. Wind erosion risk was evaluated using fuzzy logic, analytic hierarchy process, and the weighted linear combination method based on the data of climate conditions, soil physical factors, topography, and vegetation characteristics. Then, the spatial distribution characteristics and causes of different risk areas were analyzed. The following results are presented. (1) The shear strength of land use types shows an increased tendency in the order of sandy land, grassland, woodland, cultivated land, and saline land, which agreed well with the soil hardness. The soil hardness and shear strength of sandy land are 2.05 kg·cm−2 and 10.00 kPa, respectively, which are significantly lower than those of other land use types, indicating that the soil erodibility of sandy land is extremely high. (2) The wind erosion risk varied in spatial distribution. Wind erosion hazard is high in the west and south and low in the eastern and middle regions. Moreover, 27.51% of the total areas are found to be at a high risk of erosion. Thus, soil erodibility and vegetation coverage are essential factors affecting soil wind erosion. (3) The severe risk region is mainly distributed in most of Dengkou County, the edge of the south bank of the Yellow River, Togtoh County, and the east of Wuliangsuhai in the Urad Front Banner. Therefore, this area should be the focus of wind erosion control. The current research demonstrates strong universality and compensates for the shortcomings of existing wind erosion models, which can provide a theoretical basis for regional-scale wind erosion assessment models.
Subjects: Medicine, Pharmacy >> Preventive Medicine and Hygienics submitted time 2023-03-28 Cooperative journals: 《中国全科医学》
Abstract： Objective To evaluate the impact of widowhood on the mental health of older adults in China，and provide a basis and reference for formulating the mental health intervention program for older adults in China. Methods Using the 2018 China Health and Retirement Longitudinal Study （CHARLS） as the data source，4694 older adults aged 60 years and above were selected as study subjects and divided into the widowed group （n=644） and non-widowed group （n=4050）. The mental frailty index was used as a perspective for evaluating the mental health status of older adults. Using propensity score matching（PSM）model，the propensity score was calculated by using Logistic regression analysis，the robustness was tested by using standard deviation variation，common support bar graph and nuclear density distribution，the impact of widowhood on the physical and mental health of older adults was analyzed by using K-nearest neighbor matching，radius matching and kernel matching，and the heterogeneity was tested based on gender，household type and age. Results Compared to the non-widowed group，the mental health of older adults in the widowed group was impaired （P<0.001）. Logistic regression model results showed that gender，age，education level and monthly family consumption were correlated with widowhood（P<0.001）. The robustness test results after matching were better. The results of PSM showed that widowhood significantly increased the mental frailty index level（ATT ranged from 0.054 to 0.055，P<0.001）. The results of heterogeneity test showed that there were significant differences between urban and rural areas and among different age groups in the impact of widowhood on the mental frailty index of older adults，but there was no significant difference between male and female in the impact of widowhood on the mental frailty index of older adults. Among them，the impact of widowhood on the older adults in rural areas was more significant（ATT ranged from 0.072 to 0.075，P<0.001），but the impact on older adults in urban areas was not significant；the impact on older adults in the low age group and high age group was more significant（ATT ranged from 0.061 to 0.081，P<0.01；0.067~0.078，P<0.05），but the impact on older adults in the middle age group was not significant. Conclusion Widowhood has a negative impact on the mental health of the older adults. The impact varies among different older adults. The widowed older adults in rural areas，just entering old age and in their later years need attention and psychosocial support.
Subjects: Psychology >> Social Psychology submitted time 2023-03-27 Cooperative journals: 《心理学报》
Abstract： Prosocial behaviors are voluntary behaviors aimed at benefiting others, which develop rapidly during preschool and provide a foundation for children's social competence and moral development. According to the person-environment interaction (P×E) framework, children's traits may interact with the family environment, affecting their prosocial behaviors. Numerous studies have established that parent-child relationship is a crucial component of family psychosocial environments in predicting children's prosocial behaviors. Sensory processing sensitivity (SPS) is a temperament trait that reflects children's sensitivity to environmental and social stimuli. Children with high SPS are more susceptible to environmental factors. Furthermore, previous research has suggested that the Val/Val genotype of the COMT Val158Met polymorphism may be a sensitive genotype for prosociality, interacting with environmental factors to influence individuals' prosocial behaviors. In particular, prior research has proposed that different types of environmental sensitivities, such as temperamental, physiological, and genetic sensitivities, may have a multiplicative effect on social development. Parent-child relationship is an important family psychosocial environmental stimulus. More importantly, two distinct aspects of parent-child relationship, that is, closeness and conflict, may have different functions. Closeness emphasizes the parent-child connection and is characterized by emotional closeness and the sharing of private thoughts and feelings. Conversely, conflict refers to stressful experiences between parents and children that are accompanied by anger or irritation. Therefore, the present study investigated three-way interactive effects of closeness or conflict, SPS, and the COMT Val158Met polymorphism on preschoolers' prosocial behaviors. Specifically, other hypotheses regarding potential differences in closeness and conflict were formulated.A total of 507 preschoolers (Mage = 4.83, SD = 0.90; 236 girls) were recruited through advertisements at two local kindergartens. Saliva samples for DNA extraction were obtained from preschoolers. Their parents completed questionnaires on parent-child relationship, children's SPS, and prosocial behaviors. Statistical analyses were performed in SPSS 24, Mplus 8.3, and R statistical software. First, a test for Hardy-Weinberg equilibrium and preliminary analyses were conducted. Moreover, linear regression models were conducted, with prosocial behaviors as the dependent variable to test for the main and interactive effects of closeness or conflict, SPS, and genotypes. Sex, age, and family socioeconomic status were included as covariates. The effects of parent-child closeness and parent-child conflict were examined in separate models, but the other dimension of parent-child relationship was controlled in each model. Finally, region of significance and reparameterization regression analyses were employed to examine the optimal shape of the P×E effect.The results indicated that both parent-child closeness and SPS positively affected preschoolers' prosocial behaviors (ps < 0.01), while parent-child conflict was negatively associated with prosocial behaviors (p < 0.001). The two-way interaction terms (closeness/conflict × SPS; closeness/conflict × the COMT Val158Met polymorphism; SPS × the COMT Val158Met polymorphism) and the three-way interactive effect of parent-child closeness, SPS, and the COMT Val158Met polymorphism on prosocial behaviors were not significant. However, the effect of parent-child conflict × SPS × the COMT Val158Met polymorphism on prosocial behaviors was significant. We conducted further analyses to compare the interactive effect of parent-child conflict and SPS in preschoolers with the Val/Val and Met+ genotypes on the COMT Val158Met polymorphism. A significant interaction term was observed in Val/Val genotype carriers (b= -0.18, p = 0.002, 95% CI [-0.304, -0.069]) but not Met carriers (b= 0.06, p = 0.286, 95% CI [-0.052, 0.167]). The region of significance test indicated that Val/Val genotype carriers with high SPS showed significantly more prosocial behaviors under a low level of parent-child conflict and fewer prosocial behaviors under a high level of parent-child conflict, which supports the differential susceptibility model. The results of the re-parameterized regression models further verified the shape of the interaction effect of parent-child conflict and SPS on preschoolers' prosocial behaviors.In summary, the present study signified that different types of sensitivities (temperament and genes) to family stressful environments may have a multiplicative effect on preschoolers' prosocial behaviors. Furthermore, it suggested that preschoolers with both the sensitive genotype (Val/Val) and sensitive temperament trait (high SPS) were more affected by parent-child conflict and developed prosocial behaviors in a ‘‘for better and for worse'' manner. The findings provide evidence for the differential susceptibility model and contribute to a further understanding of children's prosocial behaviors based on the P×E approach, especially from the perspective of children's multiple sensitivities.
Subjects: Psychology >> Developmental Psychology Subjects: Psychology >> Cognitive Psychology submitted time 2021-10-18
Abstract： "
Peer Review Status:Awaiting Review
Subjects: Geosciences >> Geography submitted time 2021-04-23 Cooperative journals: 《干旱区研究》
Abstract：基于新疆棉铃虫生物学特性和多年的种群动态趋势，并在收集棉花种植面积、产量、棉花市场价格及棉铃虫防治费用等相关数据的基础上，采用种群模拟模型（CLIMEX模型）并结合随机模拟方法（@RISK软件），评估不同场景下棉铃虫对新疆棉花产业造成的潜在经济损失。棉铃虫种群模拟表明：随着未来气候变化，新疆棉铃虫的周增长指数（GIw）会增加，棉铃虫越冬蛹羽化的日期明显提前，危害风险可能增加；2种模拟场景结果表明，抗虫棉能有效地降低棉铃虫造成的危害，减少单位面积防治成本。建议新疆相关部门未来可通过种植抗虫棉与害虫综合治理策略（IPM）的有机结合，来减少棉铃虫及次要害虫造成的损失。
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2018-04-19 Cooperative journals: 《计算机应用研究》
Abstract： It is a common problem in many practical applications that unlabeled samples is sufficient but labeled ones is very rare. A successful method to tackle this problem is self-training semi-supervised classification. In this paper, a self-training semi-supervised classification method is introduced, in which entire data is divided into three parts based on density of data, so that the real structure of data space could be found. And then, a framework for self-training semi-supervised classification, in which the structure of data space is integrated into the self-training iterative process to help train a better classifier, is proposed. Experiments on 6 data sets from UCI show that the classifier get from the method proposed have a better performance than the ones get from supervised method with few labeled samples and standard self-training semi-supervised classification method.
Subjects: Materials Science >> Materials Science (General) submitted time 2023-03-31 Cooperative journals: 《中国腐蚀与防护学报》
Abstract： Pure Al plates were exposed in different atmospheres for 12 months at three typical test sites respectively: i.e. a rural site at Xishuangbanna of Yunnan province, an industrial site at Jiangjin of Sichuan province and a coastal site at Wanning of Hainan province. Then the corroded Al plates were characterized by means of EIS technique and SEM. The results indicate that the corrosion resistance of pure Al is the worst in the coastal atmosphere, the best in the rural atmosphere and the middle in the industrial atmosphere. Different thick layers of corrosion products were formed on Al surface in the rural and industrial atmosphere. In the contrast, a few corrosion products were formed dispersedly in the coastal atmosphere. The rate controlling step may be the diffusion of corrosive ions for the corrosion process in the coastal atmosphere, while the charge transfer for those in the rural and industrial atmospheres.
Subjects: Geosciences >> Geography submitted time 2022-03-28 Cooperative journals: 《干旱区研究》
Abstract：非灌溉季节冻融过程中土壤水盐的运动变化特征，直接影响春季作物灌水决策。本文对新疆绿洲灌区6块不同滴灌年限的棉田地块进行田间采样监测，探究冻融过程中土壤水盐运移规律以及不同滴灌年限棉田土壤盐分累积特征。结果表明：（1）随滴灌年限的增加，棉田盐分分布特征由表层聚集转变为向深层累积。（2）在冻融过程中，棉田土壤盐分运动特征存在明显的地块差异，荒地（CK）和滴灌17 a、19 a、23 a地块出现返盐趋势，平均盐分通量为43.61 gm-2d-1、172.57 gm-2d-1、38.18 gm-2d-1和10.53 gm-2d-1。（3）消融期是荒地（CK）、13 a、15 a、17 a、19 a和23 a地块水分和盐分运移最活跃的时期，冻融后所有地块敏感区（0~60 cm）土壤贮水量分别增加了23.43mm、81.26 mm、31.68 mm、62.39 mm、96.98和69.64 mm。研究揭示了冻融过程中土壤水盐运移规律以及不同滴灌年限棉田盐分累积特征，可对新疆非灌溉季冻融条件下和长期滴灌下的土壤管理提供科学指导。
Subjects: Biology >> Zoology submitted time 2017-11-08 Cooperative journals: 《动物营养学报》
Abstract：枯草芽孢杆菌是一种好氧的可直接用于人和动物的益生菌菌种，在不利条件下可以被诱导产生芽孢。芽孢具有特殊的构造及独特的生理特征，研究者们发现枯草芽孢杆菌芽孢是酶和免疫原等外源性功能蛋白的理想的锚定载体，以枯草芽孢杆菌芽孢衣壳蛋白作为分子载体，直接利用芽孢吸附作用和共价固定等方法使外源蛋白锚定在芽孢表面。目前已有多种酶蛋白、抗原蛋白和其他功能蛋白成功展示在枯草芽孢杆菌芽孢表面。本文主要对枯草芽孢杆菌芽孢结构及芽孢表面展示外源蛋白技术的策略和应用前景进行阐述。
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2022-04-07 Cooperative journals: 《计算机应用研究》
Abstract： Classic flower pollination algorithm (FPA) can be easily exposed to the shortcomings of local optimal solution and slow convergence velocity. In view of these shortcomings, this paper proposed an FPA with an enhanced lens imaging strategy and random neighborhood-based mutation strategy. The lens imaging strategy can help the algorithm avoid the shortcoming of local optimal solution by expanding the search space of FPA to increase the diversity of the solution. The introduction of random neighborhood-based mutation strategy can enhance the convergence accuracy and search speed of the algorithm by guiding algorithm search with information in the neighborhood. A comparison of the improved FPA with four other improved algorithms on CEC2013 test function found that the improved multi-strategy FPA performs better than the comparison algorithms in both convergence accuracy and search speed. To study its practical utility, this paper applies the multi-strategy FPA into the automobile transmission parameter model and the results indicate that multi-strategy FPA is better than the comparison algorithm in optimization of automobile transmission parameters.
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2020-06-30 Cooperative journals: 《干旱区研究》
Abstract：分析植被覆盖和人工扰动下戈壁地表的风沙流结构和摩阻风速与输沙率之间的关系，对保护戈壁区的生态环境具有重要意义。本文分别对植被覆盖下的戈壁地表和人工清除植被后的戈壁地表进行研究。结果显示：在不同的地表条件下，风沙流结构的变化趋势基本相同，大致可以分为3类：波动减少、先增加后减少和单调减少。受扰地表的输沙率密度大于原始地表。将摩阻风速以0.50 m·s^(-1)为界分为高、低风速。在植被覆盖的地表中，高、低风速区的输沙率与摩阻风速之间没有明显的线性相关性；而在人工清除植被后的地表，高风速区内，输沙率与摩阻风速之间满足传统的低阶多项式的关系，低风速区内两者之间则没有线性关系。
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