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Rate-limiting factors in hydrate decomposition through depressurization across various scales:A mini-review
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作者 Xian Sun Peng Xiao +7 位作者 Qinfeng Shi Lingban Wang Zhenbin Xu Yuhao Bu Xiaohui Wang Yifei Sun Changyu Sun Guangjin Chen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第3期206-219,共14页
Natural gas hydrate is an energy resource for methane that has a carbon quantity twice more than all traditional fossil fuels combined.However,their practical application in the field has been limited due to the chall... Natural gas hydrate is an energy resource for methane that has a carbon quantity twice more than all traditional fossil fuels combined.However,their practical application in the field has been limited due to the challenges of long-term preparation,high costs and associated risks.Experimental studies,on the other hand,offer a safe and cost-effective means of exploring the mechanisms of hydrate dissociation and optimizing exploitation conditions.Gas hydrate decomposition is a complicated process along with intrinsic kinetics,mass transfer and heat transfer,which are the influencing factors for hydrate decomposition rate.The identification of the rate-limiting factor for hydrate dissociation during depressurization varies with the scale of the reservoir,making it challenging to extrapolate findings from laboratory experiments to the actual exploitation.This review aims to summarize current knowledge of investigations on hydrate decomposition on the subject of the research scale(core scale,middle scale,large scale and field tests)and to analyze determining factors for decomposition rate,considering the various research scales and their associated influencing factors. 展开更多
关键词 Gas hydrate Rate-limiting factors Research scale DEPRESSURIZATION DECOMPOSITION
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贝伐珠单抗联合FAC方案治疗晚期乳腺癌的临床疗效和安全性
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作者 常哲兴 杨鑫磊 +2 位作者 罗钫月 蔡彦秋 郭浩 《临床合理用药杂志》 2024年第12期91-93,共3页
目的观察贝伐珠单抗联合FAC方案治疗晚期乳腺癌的临床疗效和安全性。方法选取2020年1月—2023年1月于北华大学附属医院肿瘤科治疗的晚期乳腺癌患者60例作为研究对象,采用随机数字表法分为FAC方案组和联合化疗组,每组30例。FAC方案组给... 目的观察贝伐珠单抗联合FAC方案治疗晚期乳腺癌的临床疗效和安全性。方法选取2020年1月—2023年1月于北华大学附属医院肿瘤科治疗的晚期乳腺癌患者60例作为研究对象,采用随机数字表法分为FAC方案组和联合化疗组,每组30例。FAC方案组给予5-氟尿嘧啶+环磷酰胺+多柔比星化疗,联合化疗组在FAC方案组基础上联合贝伐珠单抗,2组均以21 d为1个周期,持续化疗3个周期。比较2组近期疗效,化疗前后血清血小板因子4(PF4)、巨核细胞(MK)水平及欧洲癌症研究与联合化疗组织开发的生命质量测定量表(EORTC QLQ-C30)评分,不良反应,随访6个月存活率。结果联合化疗组客观缓解率、疾病控制率分别高于FAC方案组(86.67%vs.60.00%、96.67%vs.73.33%,χ^(2)/P=5.455/0.020、4.705/0.030)。化疗3个周期后,2组血清MK水平低于化疗前,且联合化疗组低于FAC方案组,联合化疗组血清PF4水平低于化疗前(P<0.01);2组EORTC QLQ-C30评分高于化疗前,且联合化疗组高于FAC方案组(P<0.01)。联合化疗组不良反应总发生率低于FAC方案组(6.67%vs.26.67%,χ^(2)=4.320,P=0.038)。随访6个月,联合化疗组存活率高于FAC方案组(60.00%vs.33.33%,χ^(2)=4.286,P=0.038)。结论贝伐珠单抗联合FAC方案治疗晚期乳腺癌可显著提高治疗效果,抑制肿瘤增长与侵袭,改善患者生活质量,提高近期存活率,且安全性较高。 展开更多
关键词 乳腺癌 晚期 贝伐珠单抗 fac方案 生活质量 巨核细胞
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基于多尺度Scale-Unet的单样本图像翻译
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作者 周蓬勃 冯龙 寇宇帆 《计算机技术与发展》 2024年第4期55-61,共7页
随着生成对抗网络(GAN)的发展,基于单样本的无监督图像到图像翻译(UI2I)取得了重大进展。然而,以前方法无法捕获图像中的复杂纹理并保留原始内容信息。为解决这个问题,提出了一种基于尺度可变U-Net结构(Scale—Unet)的新型单样本图像翻... 随着生成对抗网络(GAN)的发展,基于单样本的无监督图像到图像翻译(UI2I)取得了重大进展。然而,以前方法无法捕获图像中的复杂纹理并保留原始内容信息。为解决这个问题,提出了一种基于尺度可变U-Net结构(Scale—Unet)的新型单样本图像翻译结构SUGAN。所提出的SUGAN使用Scale—Unet作为生成器,利用多尺度结构和渐进方法不断改进网络结构,以从粗到细地学习图像特征。同时,提出了尺度像素损失scale-pixel来更好地约束保留原始内容信息,防止信息丢失。实验表明,与SinGAN、TuiGAN、TSIT、StyTR2等公共数据集Summer■Winter、Horse■Zebra上的方法相比,该方法生成图像的SIFID值平均降低了30%。所提方法可更好地保留图像内容信息,同时生成详细逼真的高质量图像。 展开更多
关键词 单样本图像翻译 scale-Unet 多尺度结构 渐进方法 尺度像素损失
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基于YOLO5Face重分布的小尺度人脸检测方法
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作者 惠康华 刘畅 《计算机仿真》 2024年第3期206-213,共8页
针对复杂场景下小尺度人脸检测精度较低的问题,提出了一种基于YOLO5Face重分布的小尺度人脸检测方法。方法以YOLO5Face为基础,在网络浅层引入改进的CBAM注意力并对模型计算重分布,提升复杂场景下小尺度人脸检测精度的同时降低模型参数量... 针对复杂场景下小尺度人脸检测精度较低的问题,提出了一种基于YOLO5Face重分布的小尺度人脸检测方法。方法以YOLO5Face为基础,在网络浅层引入改进的CBAM注意力并对模型计算重分布,提升复杂场景下小尺度人脸检测精度的同时降低模型参数量;采用融合mixup的数据增强方法,充分训练模型小尺度人脸检测分支;依据人脸检测特性,将softmax损失作为分类损失以最大化类间特征的差异。在WiderFace各个子集上的实验结果表明,与主流人脸检测方法相比,改进后的模型满足实时性的同时,小尺度人脸检测精度较高,其中Hard子集检测精度比YOLO5Face提升2个百分点。 展开更多
关键词 人脸检测 小尺度 计算重分布 分类损失
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Factor Structure and Measurement Invariance of the Japanese Version of the Mother-to-Infant Bonding Scale
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作者 Mami Yamamoto Fumie Takauma +2 位作者 Katsuhiko Tada Kaori Baba Toshinori Kitamura 《Advances in Reproductive Sciences》 2023年第4期159-170,共12页
Background: Bonding disorders affect the growth and development of infants. In Japan, the Japanese version of the Mother-to-Infant Bonding Scale (MIBS-J) is widely used for early detection of bonding disorders. Repeat... Background: Bonding disorders affect the growth and development of infants. In Japan, the Japanese version of the Mother-to-Infant Bonding Scale (MIBS-J) is widely used for early detection of bonding disorders. Repeated use of a questionnaire has problems of reduced validity. In order to correctly detect bonding disorders at multiple time points, it is necessary to confirm the measurement invariance of the scale. Baba et al. reported that invariance of the MIBS-J factor structure could only be obtained by abridging the scale into three items. Purpose: The aim of this study was to 1) confirm the factor structure and measurement invariance of the MIBS-J between two measurement times and 2) to examine factors that can be used without being affected by measurement time in order to identify item that contribute to measure met invariance. Methods: We analysed the data of 1049 and 878 mothers with a neonate collected in two waves: 5 days (Wave 1) and 1 month postpartum (Wave 2). Exploratory and confirmatory factor analyses were conducted on the data randomly divided into two groups in each wave. Results: The three-item model (MIBS-J items 1, 6, and 8) was most accepted. Measurement invariance and structural invariance were confirmed in the model. This was consistent with Baba et al.’s model. Conclusion: The three MIBS-J items showed measurement invariance and structural invariance in Japanese mothers during 1 month postpartum. 展开更多
关键词 Bonding Disorders Mother-to-Infant Bonding scale factor Analysis Measurement Invariance
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Mass-Based Environmental Factor and Energy Assessment of Microwave-Assisted Synthesized Transition Metal Nanostructures
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作者 Victor J. Law 《American Journal of Analytical Chemistry》 CAS 2024年第6期201-218,共18页
This paper describes mass-based energy phase-space projection of microwave-assisted synthesis of transition metals (zinc oxide, palladium, silver, platinum, and gold) nanostructures. The projection uses process energy... This paper describes mass-based energy phase-space projection of microwave-assisted synthesis of transition metals (zinc oxide, palladium, silver, platinum, and gold) nanostructures. The projection uses process energy budget (measured in kJ) on the horizontal axes and process density (measured in kJg−1) on the vertical axes. These two axes allow both mass usage efficiency (Environmental-Factor) and energy efficiency to be evaluated for a range of microwave applicator and metal synthesis. The metrics are allied to the: second, sixth and eleventh principle of the twelve principle of Green Chemistry. This analytical approach to microwave synthesis (widely considered as a useful Green Chemistry energy source) allows a quantified dynamic environmental quotient to be given to renewable plant-based biomass associated with the reduction of the metal precursors. Thus allowing a degree of quantification of claimed “eco-friendly” and “sustainable” synthesis with regard to waste production and energy usage. 展开更多
关键词 Microwave-Assisted Synthesis Transition Metals Nanostructures Allometry Scaling Power-Law Signature Green Chemistry
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Scale-space effect and scale hybridization in image intelligent recognition of geological discontinuities on rock slopes
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作者 Mingyang Wang Enzhi Wang +1 位作者 Xiaoli Liu Congcong Wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1315-1336,共22页
Geological discontinuity(GD)plays a pivotal role in determining the catastrophic mechanical failure of jointed rock masses.Accurate and efficient acquisition of GD networks is essential for characterizing and understa... Geological discontinuity(GD)plays a pivotal role in determining the catastrophic mechanical failure of jointed rock masses.Accurate and efficient acquisition of GD networks is essential for characterizing and understanding the progressive damage mechanisms of slopes based on monitoring image data.Inspired by recent advances in computer vision,deep learning(DL)models have been widely utilized for image-based fracture identification.The multi-scale characteristics,image resolution and annotation quality of images will cause a scale-space effect(SSE)that makes features indistinguishable from noise,directly affecting the accuracy.However,this effect has not received adequate attention.Herein,we try to address this gap by collecting slope images at various proportional scales and constructing multi-scale datasets using image processing techniques.Next,we quantify the intensity of feature signals using metrics such as peak signal-to-noise ratio(PSNR)and structural similarity(SSIM).Combining these metrics with the scale-space theory,we investigate the influence of the SSE on the differentiation of multi-scale features and the accuracy of recognition.It is found that augmenting the image's detail capacity does not always yield benefits for vision-based recognition models.In light of these observations,we propose a scale hybridization approach based on the diffusion mechanism of scale-space representation.The results show that scale hybridization strengthens the tolerance of multi-scale feature recognition under complex environmental noise interference and significantly enhances the recognition accuracy of GD.It also facilitates the objective understanding,description and analysis of the rock behavior and stability of slopes from the perspective of image data. 展开更多
关键词 Image processing Geological discontinuities Deep learning MULTI-scale scale-space theory scale hybridization
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Scale effect removal and range migration correction for hypersonic target coherent detection
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作者 WU Shang SUN Zhi +4 位作者 JIANG Xingtao ZHANG Haonan DENG Jiangyun LI Xiaolong CUI Guolong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期14-23,共10页
The detection of hypersonic targets usually confronts range migration(RM)issue before coherent integration(CI).The traditional methods aiming at correcting RM to obtain CI mainly considers the narrow-band radar condit... The detection of hypersonic targets usually confronts range migration(RM)issue before coherent integration(CI).The traditional methods aiming at correcting RM to obtain CI mainly considers the narrow-band radar condition.However,with the increasing requirement of far-range detection,the time bandwidth product,which is corresponding to radar’s mean power,should be promoted in actual application.Thus,the echo signal generates the scale effect(SE)at large time bandwidth product situation,influencing the intra and inter pulse integration performance.To eliminate SE and correct RM,this paper proposes an effective algorithm,i.e.,scaled location rotation transform(ScLRT).The ScLRT can remove SE to obtain the matching pulse compression(PC)as well as correct RM to complete CI via the location rotation transform,being implemented by seeking the actual rotation angle.Compared to the traditional coherent detection algorithms,Sc LRT can address the SE problem to achieve better detection/estimation capabilities.At last,this paper gives several simulations to assess the viability of ScLRT. 展开更多
关键词 hypersonic target detection coherent integration(CI) scale effect(SE)removal range migration(RM)correction scaled location rotation transform(ScLRT)
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Validity,Reliability,and Measurement Invariance of the Thai Smartphone Application-Based Addiction Scale and Bergen Social Media Addiction Scale
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作者 Kamolthip Ruckwongpatr Chirawat Paratthakonkun +8 位作者 Usanut Sangtongdee Iqbal Pramukti Ira Nurmala Kanokwan Angkasith Weena Thanachaisakul Jatuphum Ketchatturat Mark DGriffiths Yi-Kai Kao Chung-Ying Lin 《International Journal of Mental Health Promotion》 2024年第4期293-302,共10页
Background:In recent years,there has been increased research interest in both smartphone addiction and social media addiction as well as the development of psychometric instruments to assess these constructs.However,t... Background:In recent years,there has been increased research interest in both smartphone addiction and social media addiction as well as the development of psychometric instruments to assess these constructs.However,there is a lack of psychometric evaluation for instruments assessing smartphone addiction and social media addiction in Thailand.The present study evaluated the psychometric properties and gender measurement invariance of the Thai version of the Smartphone Application-Based Addiction Scale(SABAS)and Bergen Social Media Addiction Scale(BSMAS).Method:A total of 801 Thai university students participated in an online survey from January 2022 to July 2022 which included demographic information,SABAS,BSMAS,and the Internet Gaming Disorder Scale-Short Form(IGDS9-SF).Results:Confirmatory Factor Analyses(CFAs)found that both the SABAS and BSMAS had a one-factor structure.Findings demonstrated adequate psychometric properties of both instruments and also supported measurement invariance across genders.Moreover,scores on the SABAS and BSMAS were correlated with scores on the IGDS9-SF.Conclusion:The results indicated that the SABAS and BSMAS are useful psychometric instruments for assessing the risk of smartphone addiction and social media addiction among Thai young adults. 展开更多
关键词 factor analysis smartphone addiction social media addiction smartphone application-based addiction scale bergen social media addiction scale psychometric validation
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Scale offers the possibility of identifying adherence to lifestyle interventions in patients with non-alcoholic fatty liver disease
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作者 Cen-Qin Liu Bing Hu 《World Journal of Gastroenterology》 SCIE CAS 2024年第25期3179-3181,共3页
Nonalcoholic fatty liver disease(NAFLD)is the most common chronic liver disorder,and dietary and lifestyle interventions remain the mainstays of NAFLD therapy.Zeng et al established a prediction system to evaluate adh... Nonalcoholic fatty liver disease(NAFLD)is the most common chronic liver disorder,and dietary and lifestyle interventions remain the mainstays of NAFLD therapy.Zeng et al established a prediction system to evaluate adherence to lifestyle interventions in patients with NAFLD and choose optimal management.Here,we discuss the application scenarios of the scale and the areas warranting further attention,aiming to provide a possible reference for clinical recommend-ations. 展开更多
关键词 Nonalcoholic fatty liver disease Dietary and lifestyle interventions scale ADHERENCE EXERCISE
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Performance Improvement of Kenaf/Glass Polymer Hybrid Composites by Effective Application of Fish Scale Powder as Filler:A Novel Approach
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作者 Chandrakanta Mishra Deepak Kumar Mohapatra +2 位作者 Chitta Ranjan Deo Chetana Tripathy Kiran Kumar Ekka 《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第3期80-96,共17页
Modern technology for developing new items made from renewable resources is becoming more and more popular as a result of rising environmental concern.Recently,contemporary polymer composites have included the hybridi... Modern technology for developing new items made from renewable resources is becoming more and more popular as a result of rising environmental concern.Recently,contemporary polymer composites have included the hybridization of natural fibers with synthetic ones,along with the inclusion of a variety of biowaste filler for developing sustainable goods.In this work,the kenaf/glass hybrid polyester composites are strengthened by the addition of fish scale(FS),which is taken from the fishs outermost layer of skin.Five different stacked-order laminates,such as KKKK,KGKG,GKKG,KGGK,and GGGG,are fabricated by using the hand lay-up method with four different weight concentrations of filler content:0%,5%,10%,and 15%.Mechanical possessions such as tensile,flexural,impact strength and micro-hardness have been evaluated through experimentation in accordance with ASTM standards.The experimental findings revealed that,the tensile strength and micro-hardness value of KGKG laminates with 15wt% of FS filler are found to be maximum of 118.72 MPa and 17.82 HV respectively which are 39.67%and 26.11%greater than that of KGKG laminates without FS filler.However,the flexural and impact strength of same laminates with 10 wt% FS filler exhibited a maximum value of 142.77 MPa and 62.08 kJ/m^(2).In order to corroborate its applicability for structural and building materials in open environment,the dimensional stability of the composite has been studied through moisture absorption test.The influences of FS filler loading on dimensional stability and resistance to moisture absorption capacity of laminates are also investigated.The experimental results reflected that the addition of FS-filler has significantly improved the dimensional stability of the laminates in moist environment by reducing the moisture absorption tendency.To further support the mode of failures,a fractography investigation of fractured surfaces was conducted. 展开更多
关键词 fish scale fiber POLYESTER hybrid composites mechanical properties
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Water as a Standard Substance of a Logarithmic Poison Scale
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作者 Karsten Strey 《Journal of Biosciences and Medicines》 2024年第1期86-92,共7页
The lethal dose LD<sub>50</sub> represents the most important experimental value for acute toxicity. The simple logarithmic calculation of -log<sub>10</sub> LD<sub>50</sub> = value ... The lethal dose LD<sub>50</sub> represents the most important experimental value for acute toxicity. The simple logarithmic calculation of -log<sub>10</sub> LD<sub>50</sub> = value leads to the possible poison power pLD. As with the pH or pK value, respectively, for acid or the scale of earthquake intensities the logarithm helps making large differences of orders of magnitude easier to understand since they are more comparable. The higher the pLD value, the higher is the power of poison. An increase of the pLD value by 1 stands for a tenfold increase in toxicity. The lethal acute dose for water, one of the most important and at the same time non-toxic substances of all, is about one tenth of the body weight. This leads to a possible pLD value for water of 1, an ideal starting value for a logarithmic poison scale. 展开更多
关键词 LD50 Lethal Dose TOXICITY WATER GLYPHOSATE Poison scale
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Characterization of Small-Scale Farmers and Assessment of Their Access to Crop Production Information in Selected Counties of Kenya
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作者 Anastasia Mumbi Wahome John B. K. Kiema +1 位作者 Galcano C. Mulaku Isaac Mukoko 《Agricultural Sciences》 2024年第5期565-589,共25页
Small-scale farming accounts for 78% of total agricultural production in Kenya and contributes to 23.5% of the country’s GDP. Their crop production activities are mostly rainfed subsistence with any surplus being sol... Small-scale farming accounts for 78% of total agricultural production in Kenya and contributes to 23.5% of the country’s GDP. Their crop production activities are mostly rainfed subsistence with any surplus being sold to bring in some income. Timely decisions on farm practices such as farm preparation and planting are critical determinants of the seasonal outcomes. In Kenya, most small-scale farmers have no reliable source of information that would help them make timely and accurate decisions. County governments have extension officers who are mandated with giving farmers advisory services to farmers but they are not able to reach most farmers due to facilitation constraints. The mode and format of sharing information is also critical since it’s important to ensure that it’s timely, well-understood and usable. This study sought to assess access to geospatial derived and other crop production information by farmers in four selected counties of Kenya. Specific objectives were to determine the profile of small-scale farmers in terms of age, education and farm size;to determine the type of information that is made available to them by County and Sub-County extension officers including the format and mode of provision;and to determine if the information provided was useful in terms of accuracy, timeliness and adequacy. The results indicated that over 80% of the farmers were over 35 years of age and over 56% were male. Majority had attained primary education (34%) or secondary education (29%) and most farmers in all the counties grew maize (71%). Notably, fellow farmers were a source of information (71%) with the frequency of sharing information being mostly seasonal (37%) and when information was available (43%). Over 66% of interviewed farmers indicating that they faced challenges while using provided information. The results from the study are insightful and helpful in determining effective ways of providing farmers with useful information to ensure maximum benefits. 展开更多
关键词 Small scale Farmers FARMERS Crop Production Information Services Geospatial Information Information Access
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Factors affecting land dissection density in geomorphological regions of China
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作者 SUN Xiaolin ZHAO Yinjun +4 位作者 PENG Peihao CHENG Weiming WEI Yongping YANG Ronghao LI Jiaxu 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1372-1387,共16页
Land dissection density(LDD)provides morphological evidence regarding prior intense soil erosion and quantifies the distribution of land dissections.A comprehensive understanding of the potential factors influencing t... Land dissection density(LDD)provides morphological evidence regarding prior intense soil erosion and quantifies the distribution of land dissections.A comprehensive understanding of the potential factors influencing the spatial pattern and value of the LDD is vital in geological disasters,soil erosion,and other related domains.Land dissection phenomena in China affects large areas with different morphological,pedological,and climatic characteristics.Prior studies have focused on the potential factors influencing the LDD at a watershed scale.However,these results are insufficient to reflect the status quo of dissection development and its primary influencing factors on a national scale.LDD’s spatial patterns and the dominant factors at a regional scale in millions of square kilometers remain to be ascertained.This study used the geomorphon-based method and the geographical detector model to quantify the spatial pattern of LDD over China and identify the dominant factors affecting this pattern in China’s six first-order geomorphological regions(GR1~GR6).The results yield the following findings:(1)LDD in China ranges from 0~4.55 km/km^(2),which is larger in central and eastern regions than in other regions of China;(2)dominant factors and their dominant risk subcategories vary with each geomorphological region’s primary internal and external forces;(3)the influence of natural factors is more significant on the large regional scale in millions of square kilometers compared to anthropogenic factors;relief degree of land surface(RDLS)is dominant in GR1,GR2,and GR5;the slope is dominant in GR6,soil type is dominant in GR3 and GR4,and lithology plays a critical role in the dominant interactions of GR3,GR4,and GR6;(4)the interactions between factors on LDD’s spatial pattern have a more significant effect than individual factors. 展开更多
关键词 Land dissection density Influencing factors Regional scale Spatial pattern Geographical detector model Geomorphon-based method China
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A sub-grid scale model for Burgers turbulence based on the artificial neuralnetwork method
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作者 Xin Zhao Kaiyi Yin 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2024年第3期162-165,共4页
The present study proposes a sub-grid scale model for the one-dimensional Burgers turbulence based on the neuralnetwork and deep learning method.The filtered data of the direct numerical simulation is used to establis... The present study proposes a sub-grid scale model for the one-dimensional Burgers turbulence based on the neuralnetwork and deep learning method.The filtered data of the direct numerical simulation is used to establish thetraining data set,the validation data set,and the test data set.The artificial neural network(ANN)methodand Back Propagation method are employed to train parameters in the ANN.The developed ANN is applied toconstruct the sub-grid scale model for the large eddy simulation of the Burgers turbulence in the one-dimensionalspace.The proposed model well predicts the time correlation and the space correlation of the Burgers turbulence. 展开更多
关键词 Artificial neural network Back propagation method Burgers turbulence Large eddy simulation Sub-grid scale model
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Multi-Time Scale Operation and Simulation Strategy of the Park Based on Model Predictive Control
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作者 Jun Zhao Chaoying Yang +1 位作者 Ran Li Jinge Song 《Energy Engineering》 EI 2024年第3期747-767,共21页
Due to the impact of source-load prediction power errors and uncertainties,the actual operation of the park will have a wide range of fluctuations compared with the expected state,resulting in its inability to achieve... Due to the impact of source-load prediction power errors and uncertainties,the actual operation of the park will have a wide range of fluctuations compared with the expected state,resulting in its inability to achieve the expected economy.This paper constructs an operating simulation model of the park power grid operation considering demand response and proposes a multi-time scale operating simulation method that combines day-ahead optimization and model predictive control(MPC).In the day-ahead stage,an operating simulation plan that comprehensively considers the user’s side comfort and operating costs is proposed with a long-term time scale of 15 min.In order to cope with power fluctuations of photovoltaic,wind turbine and conventional load,MPC is used to track and roll correct the day-ahead operating simulation plan in the intra-day stage to meet the actual operating operation status of the park.Finally,the validity and economy of the operating simulation strategy are verified through the analysis of arithmetic examples. 展开更多
关键词 Demand response model predictive control multiple time scales operating simulation
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Small-scale fire tests in the underwater tunnel section model with new sidewall smoke extraction
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作者 Shunyu Yue Ruifeng Miao +2 位作者 Huihang Cheng Maohua Zhong Xiujun Yang 《Deep Underground Science and Engineering》 2024年第2期247-254,共8页
The Shenzhen–Zhongshan Bridge is a 24‐km‐long bridge and tunnel system,including a 6.8-km-long super cross section subsea tunnel.To solve the smoke exhaust problem of a super large cross-section subsea tunnel,the t... The Shenzhen–Zhongshan Bridge is a 24‐km‐long bridge and tunnel system,including a 6.8-km-long super cross section subsea tunnel.To solve the smoke exhaust problem of a super large cross-section subsea tunnel,the tunnel has a new smoke exhaust system that combines a horizontal smoke exhaust cross section at the top and sidewall smoke exhaust holes.In order to evaluate the potential fire hazards of this type of tunnel,a 1:30 tunnel model was established and 140 smallscale experiments on underwater tunnel fires were conducted.By changing the fire power,fire location,and fan operation mode,different scenarios of submarine immersed tunnel fire were simulated and the related key parameters such as fire smoke diffusion behavior and smoke temperature distribution were studied.On this basis,the optimal smoke control strategy was proposed for different fire scenarios.The research results indicate that the new smoke exhaust system can fully utilize the smoke flow characteristics,significantly improve smoke exhaust efficiency,and increase available evacuation time,thus further enhancing the fire safety of super large cross-section subsea tunnels. 展开更多
关键词 sidewall smoke extraction system small‐scale fire tests smoke control
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Study of the intensive care unit activity scale in the early rehabilitation of patients after direct cardiac surgery
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作者 Li Wang Jing-Ya Lu +1 位作者 Xiao-Xiao Ma Lan-Ou Ma 《World Journal of Clinical Cases》 SCIE 2024年第26期5930-5936,共7页
BACKGROUND Direct cardiac surgery often necessitates intensive post-operative care,and the intensive care unit(ICU)activity scale represents a crucial metric in assessing and guiding early rehabilitation efforts to en... BACKGROUND Direct cardiac surgery often necessitates intensive post-operative care,and the intensive care unit(ICU)activity scale represents a crucial metric in assessing and guiding early rehabilitation efforts to enhance patient recovery.AIM To clarify the clinical application value of the ICU activity scale in the early recovery of patients after cardiac surgery.METHODS One hundred and twenty patients who underwent cardiac surgery between September 2020 and October 2021 were selected and divided into two groups using the random number table method.The observation group was rated using the ICU activity scale and the corresponding graded rehabilitation interventions were conducted based on the ICU activity scale.The control group was assessed in accordance with the routine rehabilitation activities,and the postoperative rehabilitation indexes of the patients in both groups were compared(time of tracheal intubation,time of ICU admission,occurrence of complications,and activity scores before ICU transfer).The two groups were compared according to postoperative rehabilitation indicators(time of tracheal intubation,length of ICU stay,and occurrence of complications)and activity scores before ICU transfer.RESULTS In the observation group,tracheal intubation time lasted for 18.30±3.28 h and ICU admission time was 4.04±0.83 d,which were significantly shorter than the control group(t-values:2.97 and 2.038,respectively,P<0.05).The observation group also had a significantly lower number of complications and adverse events compared to the control group(P<0.05).Before ICU transfer,the observation group(6.7%)had few complications and adverse events than the control group(30.0%),and this difference was statistically significant(P<0.05).Additionally,the activity score was significantly higher in the observation(26.89±0.97)compared to the control groups(22.63±1.12 points)(t-value;-17.83,P<0.05).CONCLUSION Implementation of early goal-directed activities in patients who underwent cardiac surgery using the ICU activity scale can promote the recovery of cardiac function. 展开更多
关键词 Early recovery activities Goal orientated ICU mobility scale Intensive care unit Cardiac surgery
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Synoptic-scale reversal of dipole surface temperature anomalies over East Asia and Central Siberia in November 2021
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作者 Yan Kong Xinping Xu Botao Zhou 《Atmospheric and Oceanic Science Letters》 CSCD 2023年第3期33-38,共6页
2021年11月,东亚与中西伯利亚经历了相反的冷暖异常转换,表现为“中西伯利亚偏冷,东亚偏暖”与“中西伯利亚偏暖,东亚偏冷”的交替出现.该偶极型气温异常的天气尺度反转伴随着大尺度大气环流异常的反转.进一步分析表明,东亚与中西伯利... 2021年11月,东亚与中西伯利亚经历了相反的冷暖异常转换,表现为“中西伯利亚偏冷,东亚偏暖”与“中西伯利亚偏暖,东亚偏冷”的交替出现.该偶极型气温异常的天气尺度反转伴随着大尺度大气环流异常的反转.进一步分析表明,东亚与中西伯利亚的偶极型气温异常反转是1979-2021年期间11月欧亚气温日变化的主导模态之一(发生概率超过56%). 展开更多
关键词 天气尺度反转 偶极型气温异常 东亚-中西伯利亚 大尺度环流
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Multi-Time Scale Optimal Scheduling of a Photovoltaic Energy Storage Building System Based on Model Predictive Control
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作者 Ximin Cao Xinglong Chen +2 位作者 He Huang Yanchi Zhang Qifan Huang 《Energy Engineering》 EI 2024年第4期1067-1089,共23页
Building emission reduction is an important way to achieve China’s carbon peaking and carbon neutrality goals.Aiming at the problem of low carbon economic operation of a photovoltaic energy storage building system,a ... Building emission reduction is an important way to achieve China’s carbon peaking and carbon neutrality goals.Aiming at the problem of low carbon economic operation of a photovoltaic energy storage building system,a multi-time scale optimal scheduling strategy based on model predictive control(MPC)is proposed under the consideration of load optimization.First,load optimization is achieved by controlling the charging time of electric vehicles as well as adjusting the air conditioning operation temperature,and the photovoltaic energy storage building system model is constructed to propose a day-ahead scheduling strategy with the lowest daily operation cost.Second,considering inter-day to intra-day source-load prediction error,an intraday rolling optimal scheduling strategy based on MPC is proposed that dynamically corrects the day-ahead dispatch results to stabilize system power fluctuations and promote photovoltaic consumption.Finally,taking an office building on a summer work day as an example,the effectiveness of the proposed scheduling strategy is verified.The results of the example show that the strategy reduces the total operating cost of the photovoltaic energy storage building system by 17.11%,improves the carbon emission reduction by 7.99%,and the photovoltaic consumption rate reaches 98.57%,improving the system’s low-carbon and economic performance. 展开更多
关键词 Load optimization model predictive control multi-time scale optimal scheduling photovoltaic consumption photovoltaic energy storage building
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