Subjects: Geosciences >> Geography submitted time 2024-03-01 Cooperative journals: 《干旱区研究》
Abstract： Identifying priority areas for ecological compensation under soil and water conservation is animportant reference for establishing a suitable compensation system to support local ecological development. Inthis study, the Ningxia Hui Autonomous Region is taken as the study area, and the InVEST model is employed toevaluate three major soil and water conservation service functions: water connotation, soil conservation, andcarbon storage. Their respective value amounts were assessed. Additionally, the ecological compensation priorityand ecological vulnerability index of each district and county are considered to conduct a spatial identification ofpriority areas for ecological compensation for soil and water conservation in Ningxia. Research has shown thatthe value of soil and water conservation in Ningxia has steadily increased each decade from 2000 to 2020,reaching 247.89 billion yuan, 266.17 billion yuan, and 295.85 billion yuan, respectively. Geographically, thesouthern regions generally exhibit higher values, whereas the northern regions show lower values, with JingyuanCounty, Guyuan City, and Jinfeng District, Yinchuan City, representing the highest, and lowest values,respectively. Over the years, the priority compensation areas for soil and water conservation have experiencedrelatively minor changes. These areas are mainly located in the southern regions, characterized by high ecologicalvalue but economic backwardness. The secondary priority areas for ecological compensation are located in thecentral and northern regions, characterized by low ecological value but high economic development.Compensating these priority areas can effectively improve the efficiency of ecological compensation, foster theregional ecological environment, and promote sustainable economic, and social development.
Subjects: Digital Publishing >> New Media submitted time 2023-10-08 Cooperative journals: 《中国传媒科技》
Abstract：本文简单介绍如何在广播电台播控中心建立一个可靠的广播节目信号播出监测和应急播出的安全播出保障系统,如何对发射前信号和空收信号进行状态监测和监督,确保广播节目信号的安全优质播出。
Subjects: Digital Publishing >> New Media submitted time 2023-10-08 Cooperative journals: 《中国传媒科技》
Abstract：本文以安装调试意大利Elenos（意利诺斯）数字调频同步广播发射机为例,对该调频发射机的性能和远程监控系统做了阐述,并就安装调试的过程和安装调试后的搜测情况做了表述,为进一步提高调频发射台的安全播出以及提高播出质量积累了经验。
Subjects: Medicine, Pharmacy >> Clinical Medicine submitted time 2023-04-10 Cooperative journals: 《中国全科医学》
Abstract： Background Previous studies on the benefits of aerobic exercise mainly focus on the impact of aerobic exercise on long-term cardiovascular health and outcomes，namely regular aerobic exercise can improve arterial stiffness，while some studies point out that high blood sugar increases arterial stiffness. Therefore，it is supposed that hyperglycaemia may weaken the effect of aerobic exercise on improving arterial stiffness. To verify this，we used the Kailuan study data to analyze the immediate effect of aerobic exercise on arterial stiffness in people with different blood glucose levels. Objective To investigate the immediate effect of aerobic exercise on arterial stiffness in people with different blood glucose levels. Methods This study selected individuals who had participated in the 6th follow-up physical examination of the Kailuan Study during 2018—2020 and had their brachial-ankle pulse wave conduction velocity（baPWV）measured before and after the secondary load test of the power vehicle bicycle in four subordinate enterprises of Kailuan Group. Epidemiological survey result were collected：general information（age，hypertension，hyperlipidemia，history of antihypertensive drugs，etc.），anthropometric indicators〔systolic blood pressure（SBP），diastolic blood pressure（DBP），etc.〕and biochemical indicators（fasting blood glucose，etc.）. baPWV measured in the secondary load test of the power vehicle bicycle（used as the aerobic exercise） was used as an indicator of upper and lower limb arterial stiffness. baPWV-related indicators〔SBP，DBP，mean arterial pressure（MAP），heart rate（HR），baPWV，metabolic equivalent（MET），maximal oxygen uptake（VO2max），etc〕. before and after the test were expressed using a unified form，for example，pre- and post-test baPWV were recorded as baPWV 1 and baPWV 2，respectively，and its pre- and post-test difference was denoted as △ baPWV. The epidemiological survey result and BAPWV-related data were compared between fasting blood glucose（FBG） quartile groups〔Q1（n=220）：<5.00 mmol/L；Q2（n=240）：5.00-<5.40 mmol/L；Q3（n=230）：5.40-<5.81 mmol/L；Q4（n=234）：≥ 5.81 mmol/L〕. Generalized linear regression model was used to evaluate the association of FBG with pre- and post-test baPWV. Results A total of 924 eligible cases were enrolled，with an average age of（36.93±7.72）years. FBG quartile groups had statistically significant differences in mean age，hyperlipidemia and hypertension，history of using antihypertensive drugs，mean SBP，DBP，FBG，high sensitivity C-reactive protein，triglyceride，total cholesterol，high-density lipoprotein cholesterol and low-density lipoprotein cholesterol（P<0.01）. HR2 was found to be statistically significant higher than HR1 in groups Q1，Q2 and Q3（P<0.01）. baPWV2 was found to be statistically significant higher than baPWV1 in Q1，Q2，Q3 and Q4 groups（P<0.01）. SBP1，DBP1，MAP1 and baPWV1 significantly differed across the groups，and so did SBP2，DBP2，MAP2 and baPWV2（P<0.01）. Compared with baPWV1，baPWV2 decreased by an average of 36.0 cm/s in people with different blood glucose levels. The generalized linear regression model showed that after adjusting for confounding factors，the △ baPWV level in group Q1 was lower than that in group Q4〔b（95%CI）=-18.96（-36.96，-0.96），P=0.04）〕. Conclusion Aerobic exercise can immediately improve the degree of arterial stiffness，but the effect can be weakened by high blood sugar. Clinicians should design aerobic exercise programs according to the personal features of populations to improve arteriosclerosis and delay vascular aging.
Subjects: Psychology >> Developmental Psychology submitted time 2023-03-28 Cooperative journals: 《心理科学进展》
Abstract： A growing number of studies have recently focused on the functional significance of oxytocin (OT) in human social decision-making. With various experimental paradigms being developed, previous studies have shown that oxytocin (OT)plays an important regulatory role in interpersonal decision-making. In the OT research field, researchers have looked into many aspects of social decision-making, including cooperation and protection, morality, trust, generous behavior. Three possible hypotheses for oxytocin function were proposed to interpret current findings, however, no unified theory has yet been suggested to integrate all the observed phenomena. Future studies should focus on the physiological mechanisms of intranasal OT and receptor gene polymorphisms, take the gender differences into consideration, and establish a more appropriate and testable theoretical model.
Subjects: Psychology >> Developmental Psychology submitted time 2023-03-28 Cooperative journals: 《心理科学进展》
Abstract： External feedback plays a vital role in ongoing outcome monitoring and future behavioral adjustments. Previous event-related potentials (ERPs) studies have consistently associated the feedback- related negativity (FRN) component with feedback processing after decision making. Until now, several theoretical interpretations of FRN were proposed and continuously updated in the last decade, including the classical reinforcement learning theory, affective-motivational hypothesis, reward positivity (RewP) theory, Predicted response-outcome model (PRO model) and Positive affective model. Whereas different models emphasized on different aspects, no unified theory has yet been proposed to integrate all of the existing experimental evidences. Based on these literature reviews, we argued that big-sample data, multiple and complementary technologies are highly necessary in future FRN studies. Moreover, we proposed that FRN should be considered as an electrophysiological index of reward system to investigate human behaviors in complex social interaction contexts.
Subjects: Psychology >> Social Psychology submitted time 2023-03-28 Cooperative journals: 《心理科学进展》
Abstract： Working memory is an important system to store and deal with a mass of information in our daily life. On account of the limitation of working memory capacity, several memory strategies are usually adopted to promote the capacity to satisfy the needs of overloaded information processing. Chunking is one of the most common and effective memory strategies, which has an important impact on daily life and learning. It is a matter of great concern about working memory in psychology. Although previous researches have confirmed that chunking can increase the capacity of working memory, there are debates on the concept of chunking, the relationship between the structure of chunking and development of age, chunking capacity, and its works mechanism. In this case, it is still worth studying about these questions.Firstly, some previous researches proposed that the strategy of information restructuring is crucial to chunking; the others, however, agreed that the influence of common features among stimuli was more important than strategy. According to this debate of the understanding of chunking processing, the definition of chunking continues to evolve. At the same time, some researchers started to analyze the relationship between the structure of chunking and development of age. In details, there are three kinds of hierarchical organizations in this structure, which involved (1) the individual chunk formed by single and isolated item, (2) the grouping chunk based on the internal or external features' connections, and (3) the superchunk recoded or reconstructed from prior semantic knowledge and experience. Most infants before 14-month-old are in the stage of individual chunk due to their poor prior experience and immaturity of language ability. Until 14-22-month-olds, infants can use higher-order chunking to group items as their language development. Secondly, another research orientation paid more attention to the theories of chunking and its capacity. Chunking theory proposed a complete system which is responsible to retrieve and encode chunks, but it does not make distinction on whether the chunking works in short-term memory or working memory. This theory also cannot explain how an expert could storage, recall and process amount of information so rapidly. These shortcomings were compensated by template theory. The template theory, however, cannot explain how to group information under the condition of attentional resource limitation due to the lack of attentional system. Besides, embedded-processes model of working memory indicated the processing mechanism of chunking in working memory, which is embodied in the integration and extraction of attention focus in long-term memory. However, some researchers oppose to regard working memory as a part of long-term memory.In conclusion, the remarkable difference among these theories is the usage of strategies during chunking and whether it could influence on the number of chunks. According to previous researches, we found that the number of chunks in working memory is basically constant. Rehearsal strategy has influence on chunking, which leads to the dynamic change of overall chunks connection, and more flexible to respond to the memory needs of specific information in different situations.Finally, there are some issues worth concerning in the future, like (1) the role of long-term memory during chunking in working memory, (2) the influence of long-term memory on encoding and storage of chunks in working memory, (3) the features of chunks at the stages of childhood, adolescent and elderly, and (4) to abide the principle of "less is more", the way to improve the efficiency of working memory is to explore a capacity range that can maximize the function of chunking on the basis of the chunk quality, and not to expand chunk capacity in working memory.
Subjects: Psychology >> Social Psychology submitted time 2023-03-27 Cooperative journals: 《心理学报》
Abstract： The economy of action argues that individuals’ perceptions of the physical environment are related to the resources they possess. Anxiety is an emotion characterized by an unpleasant state of inner turmoil, often associated with threat or risk, that can be viewed as a manifestation of inadequate coping resources. Therefore, anxiety may affect individuals’ perceptions of the physical environment around them. Previous studies have shown that exercise influence perceptual judgments mostly based on vision-based perceptual indicators, and rarely involved stress anxiety and trait anxiety that are more common in the field of life. However, this study employed weight-based perception indicators rather than vision-based indicators to investigate the effects of two kinds of state anxiety in daily life with different mechanisms and the more stable trait anxiety on the perception of object weight, and proposed the following research hypothesis: individuals perceived objects as heavier in state or trait anxiety. In the present work, we conducted three studies to systematically investigate the effects of three types of anxiety with different attributes on the perception of weight: body posture-induced anxiety (Experiment 1), external task-induced anxiety (Experiment 2), and trait anxiety, which is stable at the personality level (Experiment 3). Participants in both Experiment 1 and Experiment 2 were asked to report their anxiety before and after the experimental task was manipulated and to judge the weight of the backpack they carried. In Experiment 1, 64 participants were randomly assigned to the anxious body posture group (n = 32) and the relaxed body posture group (n = 32) by being asked to do different body postures. In Experiment 2, 65 participants were randomly assigned to either the mental arithmetic task group (n = 33) or the odd-even task group (n = 32). In Experiment 3, based on the scores of the Trait Anxiety Inventory (T-AI) Scale, high and low scorers were selected to constitute a high-level trait anxiety group (n = 64) and a low-level trait anxiety group (n = 64), and were asked to perceive the post-test weight of the three backpacks. The results of three experiments showed that the influence of anxiety on weight perception. In Experiment 1, we found that the anxious body posture induced anxiety, and participants in the anxious body posture group perceived the weight of the object as heavier than those in the relaxed body posture group. The results of Experiment 2 revealed that the stressful mental arithmetic task induced anxiety, and participants in the mental arithmetic task group perceived the weight of the object as heavier than those in the odd-even judgment task group. The results of Experiment 3 indicated that participants in the high-level trait anxiety group perceived the weight of the object as heavier than those in the low-level trait anxiety group. The results of the three experiments suggest that either the state anxiety induced by physical changes or cognitive evaluations, or the more stable trait anxiety at the personality level, affects individuals’ perceptions of physical properties of objects, leading them to perceive objects as heavier. This study extends the indicator of perception from the visual to the weight domain at the theoretical level, validates and extends the economy of action theory again; the revealed features of weight perception of anxious individuals provide a new physical perspective for anxiety intervention, and such findings can be applied to the design of human-computer interfaces in the future, which is of great practical significance.
Subjects: Psychology >> Social Psychology submitted time 2023-03-27 Cooperative journals: 《心理学报》
Abstract： Understanding the cognitive mechanisms underlying word segmentation has been an important focus for research on Chinese reading. Previous research shows that Chinese readers can identify words very efficiently even though the Chinese script does not use spaces between words or other visual cues to demarcate word boundaries. One possibility is that Chinese readers can make use of their knowledge of the positional frequency of characters (i.e., how often they are used as the first or second character in words) to facilitate the word segmentation and recognition. Nevertheless, this potential role for position frequency remains controversial. Accordingly, with the present research we used the lexical decision task and eye movements during reading to investigate the use of positional frequency information about the first and second character of two-character words in both visual word recognition and reading. Four experiments were conducted to explore the effects of character positional frequency. In Experiments 1a and 1b, we manipulated both first and second character positional frequency (high vs. low) for target words that were of either high or low lexical frequency. Sixty college students were instructed to perform visual lexical decision tasks on words and pseudo-words. In Experiment 2a and 2b, we used measures of eye movements to investigate the use of character positional frequency in natural sentence reading. Sixty college students were required to read sentences while their eye movements were recorded using an EyeLink 1000 eye-tracker (sampling rate = 1000 Hz). The results of Experiments 1a and 1b revealed an effect of first character positional frequency in both the accuracy and latency of lexical decisions only for target words with low lexical frequency, and no effect of second character positional frequency regardless of the lexical frequency of the target word. The results of Experiment 2a and 2b showed a clear effect of first character position frequency on reading times (gaze duration, regression path reading time, and total reading time) for target words of low lexical frequency only, and no effect of second character positional frequency for either high or low frequency target words. Participants made shorter response times and fixation duration in high character positional frequency condition than in low character positional frequency condition for target words with low lexical frequency. In sum, findings from both the lexical decision task and measures of eye movements in reading reveal a privileged role for first character positional frequency as a cue to word segmentation and recognition. However, this influence of character positional frequency depends on word frequency, and is only observed for words of lower lexical frequency. We argue that these findings support the augmented addressed morphology model theory of Chinese word recognition, and can help inform the development of a model of character positional processing model in Chinese reading.
Subjects: Medicine, Pharmacy >> Clinical Medicine submitted time 2023-01-28 Cooperative journals: 《中国全科医学》
Abstract：
Objective To investigate the immediate effect of aerobic exercise on arterial stiffness in people with different blood glucose levels. Methods Those who participated in the sixth follow-up physical examination of the Kailuan Study from 2018 to 2020 and completed the brache-ankle Pulse Wave Velocity (baPWV) measurement before and after the secondary load test of the power vehicle were included in this study. According to fasting blood glucose levels, the observed subjects were grouped into quartile: Q1 (n=220) : FBG <5.00mmol/L,Q2 (n=240) : 5.00mmol/L≤ FBG <5.40mmol/L,Q3 (n=230) : 5.40mmol/L≤ FBG <5.81mmol/L,Q4 (n=234) : 5.81mmol/L≤ FBG .A generalized linear model was used to analyze the changes of baPWV before and after the secondary load test of power vehicle with different blood glucose levels. Results A total of 924 subjects met the inclusion criteria [age (36.93±7.72) years]. The baPWV measured immediately after 7 minutes of power vehicle secondary load test decreased by an average of 36cm/s from the resting level. After adjusting for confounding factors, baPWV decreased by 18.96[95%CI：-36.96,-0.96]（cm/s）more in the group with the lowest fasting glucose (Q1) than in the group with the highest fasting glucose (Q4). Conclusion Aerobic exercise can immediately improve the degree of arterial stiffness, but hyperglycemia attenuates the effect of aerobic exercise. This adverse effect was independent of traditional cardiovascular risk factors such as BMI and hypertension.
Subjects: Psychology >> Experimental Psychology submitted time 2022-08-03
Abstract： Understanding the cognitive mechanisms underlying word segmentation has been an important focus for research on Chinese reading. Previous research shows that Chinese readers can identify words very efficiently even though the Chinese script does not use spaces between words or other visual cues to demarcate word boundaries. One possibility is that Chinese readers can make use of their knowledge of the positional frequency of characters (i.e., how often they are used as the first or second character in words) to facilitate the word segmentation and recognition. Nevertheless, this potential role for position frequency remains controversial. Accordingly, with the present research we used the lexical decision task and eye movements during reading to investigate the use of positional frequency information about the first and second character of two-character words in both visual word recognition and reading. Four experiments were conducted to explore the effects of character positional frequency. In Experiments 1a and 1b, we manipulated both first and second character positional frequency (high vs. low) for target words that were of either high or low lexical frequency. Sixty college students were instructed to perform visual lexical decision tasks on words and pseudo-words. In Experiment 2a and 2b, we used measures of eye movements to investigate the use of character positional frequency in natural sentence reading. Sixty college students were required to read sentences while their eye movements were recorded using an EyeLink 1000 eye-tracker (sampling rate = 1000 Hz). The results of Experiments 1a and 1b revealed an effect of first character positional frequency in both the accuracy and latency of lexical decisions only for target words with low lexical frequency, and no effect of second character positional frequency regardless of the lexical frequency of the target word. The results of Experiment 2a and 2b showed a clear effect of first character position frequency on reading times (gaze duration, regression path reading time, and total reading time) for target words of low lexical frequency only, and no effect of second character positional frequency for either high or low frequency target words. Participants made shorter response times and fixation duration in high character positional frequency condition than in low character positional frequency condition for target words with low lexical frequency. In sum, findings from both the lexical decision task and measures of eye movements in reading reveal a privileged role for first character positional frequency as a cue to word segmentation and recognition. However, this influence of character positional frequency depends on word frequency, and is only observed for words of lower lexical frequency. We argue that these findings support the augmented addressed morphology model theory (Caramazza et al., 1988) of Chinese word recognition, and can help inform the development of a model of character positional processing model in Chinese reading.
Peer Review Status:
Awaiting Review
Subjects: Psychology >> Applied Psychology submitted time 2022-07-20
Abstract：
The economy of action argues that individuals’ perceptions of the physical environment are related to the resources they possess. Anxiety is an emotion characterized by an unpleasant state of inner turmoil, often associated with threat or risk, that can be viewed as a manifestation of inadequate coping resources. Therefore, anxiety may affect individuals’ perceptions of the physical environment around them. Previous studies have shown that exercise influence perceptual judgments mostly based on vision-based perceptual indicators, and rarely involved stress anxiety and trait anxiety that are more common in the field of life. However, this study employed weight-based perception indicators rather than vision-based indicators to investigate the effects of two kinds of state anxiety in daily life with different mechanisms and the more stable trait anxiety on the perception of object weight, and proposed the following research hypothesis: individuals perceived objects as heavier in state or trait anxiety.
In the present work, we conducted three studies to systematically investigate the effects of three types of anxiety with different attributes on the perception of weight: body posture-induced anxiety (Experiment 1), external task-induced anxiety (Experiment 2), and trait anxiety, which is stable at the personality level (Experiment 3).Participants in both Experiment 1 and Experiment 2 were asked to report their anxiety before and after the experimental task was manipulated and to judge the weight of the backpack they carried. In Experiment 1, 64 participants were randomly assigned to the anxious body posture group (n=32) and the relaxed body posture group (n=32) by being asked to do different body postures. In Experiment 2, 65 participants were randomly assigned to either the mental arithmetic task group (n=33) or the odd-even task group (n=32). In Experiment 3, based on the scores of the Trait Anxiety Inventory (T-AI) Scale, high and low scorers were selected to constitute a high-level trait anxiety group (n=64) and a low-level trait anxiety group (n=64), and were asked to perceive the post-test weight of the three backpacks.
The results of three experiments showed that the influence of anxiety on weight perception. In Experiment 1, we found that the anxious body posture induced anxiety, and participants in the anxious body posture group perceived the weight of the object as heavier than those in the relaxed body posture group. The results of Experiment 2 revealed that the stressful mental arithmetic task induced anxiety, and participants in the mental arithmetic task group perceived the weight of the object as heavier than those in the odd-even judgment task group. The results of Experiment 3 indicated that participants in the high-level trait anxiety group perceived the weight of the object as heavier than those in the low-level trait anxiety group.
The results of the three experiments suggest that either the state anxiety induced by physical changes or cognitive evaluations, or the more stable trait anxiety at the personality level, affects individuals’ perceptions of physical properties of objects, leading them to perceive objects as heavier. This study extends the indicator of perception from the visual to the weight domain at the theoretical level, validates and extends the economy of action theory again; the revealed features of weight perception of anxious individuals provide a new physical perspective for anxiety intervention, and such findings can be applied to the design of human-computer interfaces in the future, which is of great practical significance.
Peer Review Status:Awaiting Review
Subjects: Psychology >> Cognitive Psychology submitted time 2022-06-22
Abstract：
Working memory is an important system to store and deal with a mass of information. On account of the limitation of working memory capacity, several memory strategies of memory are usually adopted to satisfy the needs of overloaded information processing. Chunking is one of the most effective memory strategies, and it is a matter of great concern about working memory.
Although previous researches have confirmed that chunking can increase the capacity of working memory, there are debates on the concept of chunking, the relationship between the structure of chunking and development of age, chunking capacity, and its works mechanism. In this case, it is still worth studying about these questions.
First of all, the function of chunking in short-term memory were supposed to be storage only. Based on working memory, however, chunking was also responsible for the information processing. Secondly, chunking involved three kinds of hierarchical organizations according to its complexity, which was corresponding to various age stages. At present, few research focus on the characteristics of chunking in children and teenagers. The evidence of transition point between the second and third level was not clearly enough. Thirdly, the most popular theories of chunking were chunking theory, templates theory and embedded-processes model. The remarkable difference among these theories was the amount of chunks in working memory which was influenced by the structure of chunking and the way it works. In the future, it is worth to focus on the role of long-term memory during chunking in working memory, the features of chunks at the stages of ages, and develop the advantage of the principle of "less is more".
Peer Review Status:Awaiting Review
Subjects: Materials Science >> Electronic, Optical and Magnetic Materials Subjects: Physics >> Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics, and Fluid Dynamics submitted time 2022-05-08
Abstract：
In this work, the near ultraviolet femtosecond laser pulse is used to fabricate waveguides and Bragg gratings in poly methyl pentene (PMP). It is observed that the polymer exhibits sensitivity for the light polarization. In low NA processing, by supercontinuum spectrum estimation, the process window of peak power ranges from 2.2MW to 9.2MW. It is inferred that the nonlinear refractive index is n2387=2×10-16cm2W-1 and the third-order susceptibility χ(3) is calculated to be 1.1×10-14esu. Filamenting-process length varies from 300μm to 1500μm along with the increase of pulse energy and the length is a power function of peak energy with power index of ~ 0.53. The maximum of refractive index change is 0.01 which is inferred from the first grating diffraction efficiency, an order higher than the previous figures. These results show that the pulse peak intensity is critical to induce nonlinear absorption in terms of the two-photon absorption. The experimental data provides the latest data for scientific researchers and optical engineers.
Peer Review Status:Awaiting Review
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2020-06-21 Cooperative journals: 《干旱区研究》
Abstract：坡面微地形的发育反映了侵蚀的强度及变化过程。为了定量研究不同覆沙厚度下坡面的微地形变化与侵蚀之间的响应，通过模拟1.5mm·min-1雨强下的3场连续降雨试验，结合三维激光扫描仪技术，分析了坡面微地形与土壤侵蚀的空间变化特征，较好地拟合了微地形变幅与侵蚀量之间的关系。结果表明：坡面平均含沙量随着降雨场次的增加而减小。覆沙坡面主要产沙区的长度是黄土坡面的3倍左右，且坡段侵蚀量的峰值多分布在坡面4~6m的位置，而黄土坡面侵蚀峰值分布在3~4 m的位置。随着降雨场次的增加，黄土坡面微地形因子显著增大（P0.05）。与黄土坡面和覆沙坡面的侵蚀响应最强烈的微地形因子分别为地表切割深度和地表粗糙度，黄土坡面微地形变幅与侵蚀量的响应关系较强于覆沙坡面，覆沙坡面应寻找其他敏感的指标对方程进行优化。该研究为揭示风水复合侵蚀地区的侵蚀机理提供一定参考。
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2020-06-21 Cooperative journals: 《干旱区研究》
Abstract：为了研究冻融期土壤水分与温度的变化及其关系，通过监测野外不同土地利用径流小区土壤水分与温度数据，分析了不同深度土层土壤水分和温度的时空变化规律，阐明了研究区土壤水分与温度的相关关系。结果表明：冻融期，坡耕地20cm土层含水率变幅最大，草地和林地均为40cm土层含水率变幅最大；坡耕地20cm土层含水率变异程度最大，而草地和林地的最强活跃层分别为：30cm和10cm ；草地最先进入冻结期和融解期，且冻结和融解时间逐层滞后；3种地类(坡耕地、林地、草地）土壤含水率与温度均呈二次函数关系。林地土壤水分与温度的相关性最强，更有利于黄土区土壤水-热保持，该结果可为黄土区土壤水分对植被恢复影响研究以及环境建设保护提供科学依据。
Subjects: Environmental Sciences, Resource Sciences >> Basic Disciplines of Environmental Science and Technology submitted time 2020-06-19 Cooperative journals: 《干旱区研究》
Abstract： 为了研究冻融期土壤水分与温度的变化及其关系，通过监测野外不同土地利用径流小区土壤水分与温度数据，分析了不同深度土层土壤水分和温度的时空变化规律，阐明了研究区土壤水分与温度的相关关系。结果表明：冻融期，坡耕地20cm土层含水率变幅最大，草地和林地均为40cm土层含水率变幅最大；坡耕地20cm土层含水率变异程度最大，而草地和林地的最强活跃层分别为：30cm和10cm ；草地最先进入冻结期和融解期，且冻结和融解时间逐层滞后；3种地类(坡耕地、林地、草地）土壤含水率与温度均呈二次函数关系。林地土壤水分与温度的相关性最强，更有利于黄土区土壤水-热保持，该结果可为黄土区土壤水分对植被恢复影响研究以及环境建设保护提供科学依据。
Subjects: Astronomy >> Astrophysical processes submitted time 2020-05-12 Cooperative journals: 《天文研究与技术》
Abstract：噪声注入定标方法作为厘米波段一种常规强度校准方式而被广泛使用。通过组建K波段常温接收机及其定标平台，在室内20℃下使用传统冷热负载法标定接收机噪声温度及噪声源温度，之后在室外-7℃中使用同样方法再次标定上述参数，并利用室内标定的噪声源去进一步标定室外环境中接收机的噪声温度。测试结果表明，在环境温度变化约27度时，接收机噪声温度定标差异约为50.5%，标准噪声源定标差异约为41%。故此得知，如若将噪声注入法应用于常温接收机定标中，首先需考虑对接收机进行恒温处理，另外可采取对注入的标准噪声源进行温度补偿，使其可以更加精确的应用于二次定标当中，这也是本论文下一步计划开展的工作。
Subjects: Materials Science >> Electronic, Optical and Magnetic Materials submitted time 2019-04-30
Abstract： CsKNaLi(Li3SiO4)4:Eu2+ (CKNLLSO:Eu2+) as a new member of oxide-based family with UCr4C4-related type structure was first synthesized successfully. The crystal and band structure of the host compound was characterized and analyzed by aid of Rieveld refinement and density functional theory, respectively. As a result of the highly condensed and rigid anion framework, Eu2+ substituting Cs site gives intense green emission with a narrow full width at half maximum of 55 nm excited by InGaN-based near UV LEDs. The CKNLLSO:Eu2+ phosphor exhibits relatively high thermal stability even though the temperature was raised to 190 ℃. The LED fabricated using the optimized CKNLLSO:4%Eu2+ phosphor demonstrated bight and narrow green light with chromaticity coordinate (0.2320, 0.6016) and correlated color temperature 7314 K, implying its great potential for applications as green components for white LEDs.
Peer Review Status:Awaiting Review
Subjects: Computer Science >> Integration Theory of Computer Science submitted time 2018-12-13 Cooperative journals: 《计算机应用研究》
Abstract： Existing object detection algorithms are mainly aimed at detecting big objects in an image. Research on small object detection is still too scarce and there are problems with low detection accuracy and failure to meet the real-time requirement. This paper proposed a real-time small object detection method based on deep learning framework PVANet. Firstly, it built a benchmark dataset especially for small object detection problem. The dataset consisted of small objects covering a very small part of an image and also contained some interferences such as truncation and overlap. Secondly, combining with the Region Proposal Network (RPN) , it designed a strategy to generate high-quality candidate proposals for small objects to raise the detection accuracy and speed. Finally, it adopted two new learning rate policies "step" and "inv" to further enhance the detection accuracy. The proposed method achieved the mAP(mean average precision) by 10.67% and speed by 30% improvement over the original PVANet algorithm. Experimental results shows that this method is effective on small object detection and can run in real time.
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