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I'll Check It Out
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作者 Ruth Devlin 《空中英语教室(初级版.大家说英语)》 2026年第1期34-35,56,54,共4页
You can use the word“check”in many ways.When you check into something,you find out more about it.When you check something out,you look at that thing carefully.To check out a place,you may actually go there.When you ... You can use the word“check”in many ways.When you check into something,you find out more about it.When you check something out,you look at that thing carefully.To check out a place,you may actually go there.When you check in on someone,you go to their place.You may ask,“How are you doing?” 展开更多
关键词 PLACE check something check find more checkin SOMEONE checkout
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Prediction-Powered Model Checking via Predictiveness Comparisons
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作者 LIU Yanhong JIA Yinxu +2 位作者 WANG Guanghui WANG Zhaojun ZOU Changliang 《Journal of Systems Science & Complexity》 2026年第1期115-135,共21页
Model checking evaluates whether a statistical model faithfully captures the underlying data-generating process.Classical tests—such as local-smoothing and empirical-process methods—break down in high dimensions.Mor... Model checking evaluates whether a statistical model faithfully captures the underlying data-generating process.Classical tests—such as local-smoothing and empirical-process methods—break down in high dimensions.More recent approaches use predictiveness comparisons with flexible machine-learning model fitting procedures to yield algorithm-agnostic tests,yet they require large labeled samples.The authors introduce a prediction-powered,semi-supervised framework that:1)Imputes responses for unlabeled data via a pretrained model;2)Corrects imputation bias with a rectifier calibrated on labeled data;3)Adaptively balances these components through a data-driven power-tuning parameter.Building on algorithm-agnostic out-of-sample predictiveness comparisons,the proposed method integrates unlabeled information to enhance power.Theoretical analyses and numerical results demonstrate that the proposed test controls Type I error and substantially improves power over fully supervised counterparts,even under imputation-model misspecification. 展开更多
关键词 Algorithm-agnostic inference asymptotic normality model checking prediction-powered inference semi-supervised inference
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Model Checking for Parametric Regressions in Transfer Learning
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作者 WANG Chuhan HUANG Jiaqi LI Xuerui 《Journal of Systems Science & Complexity》 2026年第1期17-37,共21页
This paper examines whether the parametric regression model is correctly specified for both source and target data and whether the regression pattern in the source domain aligns with that of the target domain.This eva... This paper examines whether the parametric regression model is correctly specified for both source and target data and whether the regression pattern in the source domain aligns with that of the target domain.This evaluation is a critical prerequisite for applying model-based transfer learning methods under covariate shift assumptions.Traditional regression model checks and twosample regression tests are insufficient to address this issue.To overcome these limitations,the authors propose a novel adaptive-to-regression test statistic that is asymptotically distribution-free.Under the null hypothesis,the test follows a chi-square weak limit,preserving the significance level and enabling critical value determination without resampling techniques.Additionally,the authors systematically analyze the test's power performance,highlighting its sensitivity to different sub-local alternatives that deviate from the null hypothesis.Numerical studies,including simulations,assess finite-sample performance,and a real-world data example is provided for illustration. 展开更多
关键词 Adaptive-to-model test asymptotically distribution-free model checking parameter regression transfer learning
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Special Issue“Recent Developments in Dimension Reduction and Model Checking”——In Honor of Professor Lixing Zhu's Outstanding Contributions in Statistics
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作者 ZHU Liping XU Wangli LI Yingxing 《Journal of Systems Science & Complexity》 2026年第1期1-2,共2页
The proliferation of high-dimensional data and the widespread use of complex models present central challenges in contemporary statistics and data science.Dimension reduction and model checking,as two foundational pil... The proliferation of high-dimensional data and the widespread use of complex models present central challenges in contemporary statistics and data science.Dimension reduction and model checking,as two foundational pillars supporting scientific inference and data-driven decisionmaking,have evolved through the collective wisdom of generations of statisticians.This special issue,titled"Recent Developments in Dimension Reduction and Model Checking for regressions",not only aims to showcase cutting-edge advances in the field but also carries a distinct sense of academic homage to honor the groundbreaking and enduring contributions of Professor Lixing Zhu,a leading scholar whose work has profoundly shaped both areas. 展开更多
关键词 scientific inference model checking model checkingas complex models dimension reduction high dimensional data
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ReChecker:基于模型检测的智能合约重入漏洞检测方法
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作者 柴新卓 刘国玺 +2 位作者 李乐成 代飞 黄苾 《计算机集成制造系统》 北大核心 2026年第3期1011-1024,共14页
智能合约的重入漏洞检测是保障其安全性的重要技术手段之一。现有基于符号执行、模糊测试和模型检测方法,只考虑了无锁智能合约,未考虑有锁智能合约的重入漏洞检测。有效建模智能合约并定义重入漏洞的安全性质具有挑战性。本文提出了一... 智能合约的重入漏洞检测是保障其安全性的重要技术手段之一。现有基于符号执行、模糊测试和模型检测方法,只考虑了无锁智能合约,未考虑有锁智能合约的重入漏洞检测。有效建模智能合约并定义重入漏洞的安全性质具有挑战性。本文提出了一种基于模型检测的智能合约重入漏洞检测方法(ReChecker),将智能合约细分为有锁智能合约和无锁智能合约,结合检查-生效-交互模式(CEI)和锁机制,实现对智能合约重入漏洞的自动检测。首先,基于抽象语法树(AST),将智能合约源代码建模为标号迁移系统(LTS);其次,从执行顺序和访问控制视角,使用线性时序逻辑(LTL)公式分别定义了基于CEI模式和基于锁机制的重入漏洞安全性质;然后,在进程分析工具(PAT)的支持下,自动化地检测了有锁智能合约和无锁智能合约是否会发生重入漏洞。最后,为了验证所提方法的有效性,在3个数据集上进行了实验,实验结果表明:相比5种基准方法,ReChecker的准确率平均提升了10.83%,漏报率和误报率平均降低了12%和17.5%. 展开更多
关键词 智能合约 重入漏洞 模型检测 抽象语法树 标号迁移系统 线性时序逻辑
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Check韧带悬吊术治疗重度先天性上睑下垂 被引量:2
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作者 仓正强 郝冬月 +2 位作者 孙黎明 宋保强 刘超华 《组织工程与重建外科》 2025年第5期436-440,共5页
目的探讨Check韧带悬吊术治疗重度先天性上睑下垂的手术效果。方法采用单中心回顾性研究,纳入2022年6月至2023年12月期间接受Check韧带悬吊术治疗的重度先天性上睑下垂患者。收集的术前数据包括年龄、性别、上睑缘角膜映光距离(MRD1)、... 目的探讨Check韧带悬吊术治疗重度先天性上睑下垂的手术效果。方法采用单中心回顾性研究,纳入2022年6月至2023年12月期间接受Check韧带悬吊术治疗的重度先天性上睑下垂患者。收集的术前数据包括年龄、性别、上睑缘角膜映光距离(MRD1)、提肌功能和眼睑闭合不全情况。在最后一次随访时进行术后评估,包括矫正效果和眼睑闭合功能。结果本研究共纳入86例患者(125眼),术后MRD1较术前显著改善(P<0.001),115只眼成功矫正。术后平均眼睑闭合不全缝隙为(0.58±0.57)mm,119只眼睑闭合功能极好或良好。结论Check韧带悬吊术治疗重度先天性上睑下垂能够获得良好的矫正效果,且矫正不足、残余睑裂闭合不全和结膜脱垂等并发症较少。 展开更多
关键词 check韧带 重度先天性上睑下垂 争议 并发症
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Check dams on China's Loess Plateau:An overview 被引量:1
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作者 Zuyu Chen Shujing Chen +2 位作者 Penghai Yin Shu Yu Naichang Zhang 《River》 2025年第1期1-20,共20页
Check dams are widely constructed on China's Loess Plateau,which had a total number of 58,776 by the end of 2019.Great achievements in check dam construction have been gained regarding the economic and environment... Check dams are widely constructed on China's Loess Plateau,which had a total number of 58,776 by the end of 2019.Great achievements in check dam construction have been gained regarding the economic and environmental impacts.This study reviews the remarkable benefits of check dams on the land reclamation and environmental improvement on the Loess Plateau,and sediment reduction entering the Yellow River.However,the flood incidents on check dams have been frequently reported for the past decades,which has attracted more attention in the context of climate change and extreme rainfall events recently.Advances in the flood migration techniques achieved by the research group led by the first author have been highlighted to migrate the breach risk of check dams due to floods.The“family tree method”has been proposed to determine the survival status and critical rainfall threshold of each check dam in the complicated dam system.An updated dam breach flood evaluation framework and the corresponding numerical algorithm(i.e.,DB-IWHR)have been developed.Moreover,innovative types of water-release facilities for check dams,including geobag stepped spillway and prestressed concrete cylinder pipe in the underlying conduit,have been proposed and developed.Finally,the perspectives concerning the check dam construction on the Loess Plateau have been put forward. 展开更多
关键词 check dams China's Loess Plateau DB-IWHR “family tree method” geobag stepped spillway
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Implication of odd-even staggering in the charge radii of calcium isotopes
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作者 Rong An Xiang Jiang +2 位作者 Na Tang Li-Gang Cao Feng-Shou Zhang 《Communications in Theoretical Physics》 2025年第10期174-183,共10页
Inspired by the profoundly observed odd-even staggering and the inverted parabolic-like shape in charge radii along calcium isotopic chain,the ground state properties of calcium isotopes are investigated by constraini... Inspired by the profoundly observed odd-even staggering and the inverted parabolic-like shape in charge radii along calcium isotopic chain,the ground state properties of calcium isotopes are investigated by constraining the root-mean-square charge radii under the covariant energy density functionals with effective forces NL3 and PK1.In this work,the pairing correlations are tackled by solving the state-dependent Bardeen-Cooper-Schrieffer equations.The calculated results suggest that the binding energies obtained by the radius constraint method have been slightly changed by about 0.2%.But for charge radii,the corresponding results deriving from NL3 and PK1 forces have been increased by about 1.0%and 2.0%,respectively.This means that the charge radius is a more sensitive quantity in the calibrated protocol.Meanwhile,it is found that the reproduced charge radii of calcium isotopes are attributed to the rather strong isospin dependence of effective potential.The odd-even oscillation behavior can also be presented in the proton Fermi energies along calcium isotopic family,but keep opposite trends with respect to the corresponding binding energies and charge radii.As encountered in charge radii,the weakened odd-even oscillation behavior still emerged from the proton Fermi energies at the neutron numbers N=20 and 28 as well,but not in binding energies. 展开更多
关键词 shell closure effect odd-even staggering charge radii covariant energy density functionals
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Evaluating the sediment control and transport of cascade check dams at Guanmenzi Gully, Beichuan County, China
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作者 HUANG Diwen YOU Yong +3 位作者 SUN Hao LIU Daochuan WANG Dongwei ZHANG Jingyu 《Journal of Mountain Science》 2025年第11期4052-4071,共20页
The implementation of the cascade check dam system, which integrates beam and closed-type dams, has been extensively adopted as a pivotal engineering measure for mitigating debris flow in Southwest China. In the post-... The implementation of the cascade check dam system, which integrates beam and closed-type dams, has been extensively adopted as a pivotal engineering measure for mitigating debris flow in Southwest China. In the post-debris flow events, it is imperative to quantitatively assess the volume of sediment volume captured by the cascade check dams and to monitor their impact on sediment dynamics. This study investigates the cascade check dams in Guanmenzi Gully, Beichuan County, Sichuan Province in Southwest China, surveying the reservoir topography of the dams on two occasions over a fiveyear period. The #3 closed-type dam, located in the upper upstream, the #2 closed-type dam, located in the middle stream(which was manually cleaned), and the beam dam, located in the downstream were all surveyed. A simplified yet accurate method was developed to estimate sediment volume within check dam reservoirs under complex topographic conditions. A combination of terrestrial surveys and Unmanned Aerial Vehicle(UAV) based surveys was employed, resulting in the acquisition of two high-resolution Digital Elevation Models(DEMs) at different temporal intervals. The utilization of DEMs of Difference(DoD) facilitated the quantification of terrain variations and the sediment transport. The following conclusions were obtained: firstly, it was found that the volume of sediment trapped in the reservoirs of #2 closed-type dam and #1 beam dam were almost the same, with #3 closed-type dam being the smallest. The validation of the results in conjunction with the geometric method demonstrated that the percentage error was less than 7%, proving the reliability of the results. In addition, an analysis of changes in the detailed topography of the reservoirs revealed that the sediment deposit occurred in areas distant from the structures, while erosion exhibited concentration in specific areas close to the dams. The percentage volume of sediment deposit was found to be significantly higher than that of erosion(all higher than 85%). Furthermore, the excessive sediment deposition reduces the storage capacity of closed-type check dams, whereas in the case of beam dams, the maximum erosion amount in the reservoir is 35.8 m^(3) and the percentage of the maximum erosion amount is 14.00%. This suggests that the self-cleaning of beam dam can effectively slow down the sediment deposition process. Finally, the current study proposes an expression for storage capacity composition and suggests that, in engineering practice, emphasis should be placed on maintenance programs that synergize manual cleaning and self-cleaning of open-type check dams. The conclusions may facilitate the refinement of maintenance strategies of cascade check dams, thereby effectively preventing and mitigating debris flows. 展开更多
关键词 Cascade check dams Storage capacity Sediment transport DEMs of Difference(DoD)
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Covering the biopsy hole check valve with“enzymolysis gauze”reduces bacterial contamination in the endoscopy room
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作者 Hu-Bin Xia Ying-Dong Hou +7 位作者 Yuan Zhang Ai-Yu Yu Qi Ding Wen-Li Ruan Yi-Shen Mao Shu-Jiong Feng Cong Ding Yi-Feng Zhou 《World Journal of Gastroenterology》 2025年第44期137-146,共10页
BACKGROUND Bacterial contamination during colonoscopy is a significant concern,yet few studies have evaluated bacterial aerosols.This study aimed to determine whether covering the biopsy hole check valve with enzymoly... BACKGROUND Bacterial contamination during colonoscopy is a significant concern,yet few studies have evaluated bacterial aerosols.This study aimed to determine whether covering the biopsy hole check valve with enzymolysis gauze(refers to sterile gauze soaked in a multi-enzyme cleaning solution)reduces bacterial air pollution in endoscopy rooms.AIM To evaluate the efficacy of an enzymolysis gauze cover in reducing bacterial aerosols from the biopsy valve.METHODS This prospective,single-blind trial included 80 patients undergoing elective diagnostic colonoscopy.During the procedure,the biopsy hole check valve was either covered or left uncovered with enzymolysis gauze.Air samples(100 L)were collected at a distance of 30 cm from the biopsy hole check valve and approximately 140 cm above the floor using a percussive air sampling instrument.Gram-positive bacteria were cultured on standard 90 mm colimycin nalidixic agar blood plates.The primary outcome measures were bacterial load and species identification.RESULTS Covering the biopsy hole check valve with enzymolysis gauze reduced bacterial load near the check valve from 50 colony-forming unit(CFU)/m^(3)[interquartile range(IQR):30-80]to 20 CFU/m^(3)(IQR:10-20).At the end of the procedure each day,covering the valve also decreased bacterial load in the endoscopy room from 35 CFU/m^(3)(IQR:33-85)to 10 CFU/m^(3)(IQR:5-10).The predominant bacteria identified were Gram-positive cocci.CONCLUSION Applying enzymolysis gauze to cover the biopsy hole check valve significantly reduces bacterial aerosol contamination in endoscopy rooms during colonoscopy. 展开更多
关键词 Bacterial contamination Aerosol Enteric bacterial microflora Colonoscope ENDOSCOPY Enzymolysis gauze Biopsy hole check valve Infection
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黄土高原典型淤地坝溃决的界面促渗与水力激发促溃机制 被引量:1
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作者 祝艳波 姚俊义 +4 位作者 张宇轩 彭建兵 兰恒星 李福通 田王慧 《工程地质学报》 北大核心 2026年第1期264-277,共14页
黄土高原极端暴雨下淤地坝溃决事件频发,查明淤地坝的防洪标准、显著的界面促渗效应、极端暴雨水力激发下的溃决机制至关重要。为此采用野外调查、现场监测、室内试验等手段开展典型治沟造地小流域淤地坝的水毁溃决机制研究,以揭示淤地... 黄土高原极端暴雨下淤地坝溃决事件频发,查明淤地坝的防洪标准、显著的界面促渗效应、极端暴雨水力激发下的溃决机制至关重要。为此采用野外调查、现场监测、室内试验等手段开展典型治沟造地小流域淤地坝的水毁溃决机制研究,以揭示淤地坝水毁破坏模式、坝体渗流特征、渐进溃决机制。结果表明:(1)典型淤地坝水毁破坏可分为坝体变形与坝体破坏两类。其中坝体变形可分为坝顶沉降、坝坡滑塌两类,坝体破坏可分为管涌式溃坝、滑移式溃坝、漫顶式溃坝3类;(2)淤地坝特殊地质结构诱导了差异的坝坡渗流规律,导致了坝体差异的渐进式水毁破坏特征。疏松坝体易诱导强渗流浸润软化坝体,造成坝顶沉降及坝体渐进滑塌;挖填、堆填软弱界面易诱导优势渗流,造成坝体沿界面软弱带、软弱区产生渗透变形破坏;(3)极端暴雨短时激发了坝体强渗流、快速放大了界面优先流,导致坝体内孔隙水压力激增,渗透力沿界面带快速冲蚀土体使坝坡产生管涌破坏、沿界面区快速冲剪土体使坝坡产生滑移破坏。研究成果从界面促溃角度揭示了黄土高原淤地坝频繁溃决的水力激发机制,为淤地坝高防洪标准建设及关键防溃技术提出提供重要参考。 展开更多
关键词 黄土高原 淤地坝 水毁溃决 界面促渗 水力激发
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铁路车站能力计算与协调运用研究综述
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作者 薛锋 李佳霖 +2 位作者 徐俊林 古旭 陈崇双 《铁道运输与经济》 北大核心 2026年第1期1-14,共14页
能力作为衡量铁路车站设备作业效能和运输组织水平的核心指标,对提升车站运输效率、保障运输安全至关重要。围绕铁路车站能力计算、查定及协调运用的方法及发展趋势展开系统综述。在能力计算方面,传统的咽喉区、到发线与驼峰等静态指标... 能力作为衡量铁路车站设备作业效能和运输组织水平的核心指标,对提升车站运输效率、保障运输安全至关重要。围绕铁路车站能力计算、查定及协调运用的方法及发展趋势展开系统综述。在能力计算方面,传统的咽喉区、到发线与驼峰等静态指标分析逐步发展为动态模拟预测,并进一步延伸至站间能力的优化;在能力查定方面,从计算机联锁技术发展为多源信息数据融合方法;在能力协调运用方面,涵盖车站系统内部的能力协调,以及车站与衔接线路的点线能力匹配。综合既有研究成果,从车站能力计算查定、协调运用与自动化监测方面提出进一步研究的展望,为车站作业的精细化管控以及安全高效的铁路运输体系构建提供参考。 展开更多
关键词 铁路运输 车站 能力计算 协调运用 查定技术
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基于温室气体自愿减排项目方法学的淤地坝碳汇量监测核算方法 被引量:1
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作者 李智广 王海燕 +3 位作者 熊锐 成辉 李蔚 金宇曦 《中国水土保持》 2026年第2期27-32,I0001,共7页
淤地坝具有保土保碳、减蚀减排和增绿增汇作用,其碳汇项目开发对促进淤地坝工程建设和运行管护、助力黄河流域生态保护与实现“双碳”目标具有重要意义。2025年11月25日,生态环境部与水利部发布《温室气体自愿减排项目方法学淤地坝碳汇... 淤地坝具有保土保碳、减蚀减排和增绿增汇作用,其碳汇项目开发对促进淤地坝工程建设和运行管护、助力黄河流域生态保护与实现“双碳”目标具有重要意义。2025年11月25日,生态环境部与水利部发布《温室气体自愿减排项目方法学淤地坝碳汇》,为淤地坝碳汇项目开发和碳汇量监测核算提供了技术规范。结合编制情况,依据方法学关于碳汇量监测核算的规定,系统阐述了淤地坝碳汇项目的时间范围、空间范围、基准线情景识别、项目减排量核算方法,明确了获取项目边界、坝地面积、坝地表层30 cm土壤体积和土壤有机碳含量等关键参数和数据所必需的样品采集、测定和计算的方法,可为项目业主及监测核算机构提供实操参考,对推动淤地坝碳汇项目的规范开发和科学实施具有指导作用。 展开更多
关键词 水土保持 淤地坝 碳汇项目 项目方法学 监测核算
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降雨诱发的黄土高原淤地坝溃决灾害快速动态评价研究
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作者 王琳 唐倩 +2 位作者 于沭 薛一峰 单熠博 《岩土工程学报》 北大核心 2026年第2期386-394,共9页
超标准降雨导致淤地坝溃决事件频发,亟需开展黄土高原淤地坝溃决灾害快速动态评价研究。以降雨诱发的淤地坝溃决灾害过程为研究核心,构建“雨-洪-沙-溃”灾害评价方法,将“土-水-沙”耦合作用贯穿于溃决灾害全过程,建立淤地坝水沙动力-... 超标准降雨导致淤地坝溃决事件频发,亟需开展黄土高原淤地坝溃决灾害快速动态评价研究。以降雨诱发的淤地坝溃决灾害过程为研究核心,构建“雨-洪-沙-溃”灾害评价方法,将“土-水-沙”耦合作用贯穿于溃决灾害全过程,建立淤地坝水沙动力-溃坝数学模型。并以王茂沟流域2012年“7·15”降雨为实例,开展淤地坝溃决状态快速判定、泥沙补给突变溃决影响规律研究、危险坝体快速定位研究,从而实现溃决灾害快速动态评价。结果表明:采用水沙动力-溃坝数学模型判定黄柏沟^(#)1坝、康河沟^(#)1坝和康河沟^(#)2坝溃决,结果符合实际溃决情况;考虑降雨诱发的径流激增和泥沙补给突变对溃决灾害评价的影响,黄柏沟^(#)1坝、康河沟^(#)1坝和康河沟^(#)2坝洪峰时间分别提前24,21,26 min,洪峰流量分别增大4.24%,1.53%,4.76%,洪峰时间提前,洪峰流量偏大,结果偏安全,有助于提前发出预警;随着降雨量的增大,忽略泥沙作用时所判定的溃坝数量均小于考虑泥沙作用时所判定的结果,泥沙作用不可忽视。 展开更多
关键词 淤地坝 雨-洪-沙-溃 溃决灾害评价 泥沙补给突变
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动机行为转化下的节点式标准化健康教育对肿瘤患者PET-CT探查转移灶检查配合度的影响
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作者 赵丽 秦乡音 +3 位作者 张会娟 李倩 王萌 李佳 《齐鲁护理杂志》 2026年第1期154-157,共4页
目的:探讨动机行为转化下的节点式标准化健康教育对肿瘤患者正电子发射计算机断层显像(PET-CT)探查转移灶检查配合度的影响。方法:选取2022年8月—12月于核医学科进行PET-CT探查转移灶检查的92例肺癌患者,随机分为观察组和对照组各46例... 目的:探讨动机行为转化下的节点式标准化健康教育对肿瘤患者正电子发射计算机断层显像(PET-CT)探查转移灶检查配合度的影响。方法:选取2022年8月—12月于核医学科进行PET-CT探查转移灶检查的92例肺癌患者,随机分为观察组和对照组各46例,对照组给予PET-CT检查常规护理,观察组在此基础上予以动机行为转化下的节点式标准化健康教育;比较检查配合度、干预前后焦虑抑郁水平[焦虑自评量表(SAS)和抑郁自评量表(SDS)]、护理满意度、干预前后生活质量[生命质量量表(QLQ-C30)]。结果:观察组检查配合度及护理满意度均高于对照组(P<0.05);观察组SAS、SDS评分均低于对照组(P<0.01),QLQ-C30评分高于对照组(P<0.01)。结论:动机行为转化下的节点式标准化健康教育能提高肿瘤患者PET-CT探查转移灶检查期间的配合度,降低焦虑、抑郁水平,提高患者护理满意度,改善患者生活质量。 展开更多
关键词 肿瘤患者 动机行为转化 健康教育 检查配合度
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超大型螺旋压力机主驱动用节能型行星滚柱丝杠设计理论与仿真研究
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作者 赵升吨 尚仕涵 +9 位作者 陈开达 胡阳虎 李帆 曹杨峰 张传伟 黄晓鹏 范淑琴 马海宽 周路 宁博 《锻压装备与制造技术》 2026年第1期1-10,共10页
针对现有螺旋压力机主驱动螺旋副采用滑动摩擦方式存在的能量浪费严重、寿命低、维护成本高等不足,本文积极倡导在螺旋压力机尤其是超大型螺旋压力机主驱动使用能量利用率至少比滑动摩擦方式提高一倍的行星滚柱丝杠。以最大冷击力达365M... 针对现有螺旋压力机主驱动螺旋副采用滑动摩擦方式存在的能量浪费严重、寿命低、维护成本高等不足,本文积极倡导在螺旋压力机尤其是超大型螺旋压力机主驱动使用能量利用率至少比滑动摩擦方式提高一倍的行星滚柱丝杠。以最大冷击力达365MN的超大型离合器式电动螺旋压力机为对象,按照运动学和强度理论,分析计算了该设备以标准式行星滚柱丝杠为主驱动的螺旋压力机核心关键几何参数。为验证核心受力部件的结构强度与可靠性,采用Abaqus大型有限元分析软件,对丝杠与滚柱接触侧的单个螺纹牙进行精细的静力学仿真计算,确保设计方案在极限载荷下的安全性。通过Adams动力学建模,对于行星滚柱丝杠副进行受载状态下的仿真分析,将各参数的仿真结果与理论值进行对比,验证了行星滚柱丝杠副的工程可行性,为行星滚柱丝杠应用于螺旋压力机奠定坚实基础。 展开更多
关键词 螺旋压力机 行星滚柱丝杠 运动学 强度校核 仿真
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基于校验码猜测生日码的Python实现
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作者 黄绍龙 刘华煜 《计算机应用文摘》 2026年第6期99-101,共3页
身份证是公民身份信息的重要载体,身份证号码是其主要特征信息。由于实际生活需求,身份证图片可能会暴露在网络上,即使部分号码被隐藏,仍然存在隐私泄露的风险。文章假设了在未知生日码的情况下,利用身份证号码的校验码推测出可能的生... 身份证是公民身份信息的重要载体,身份证号码是其主要特征信息。由于实际生活需求,身份证图片可能会暴露在网络上,即使部分号码被隐藏,仍然存在隐私泄露的风险。文章假设了在未知生日码的情况下,利用身份证号码的校验码推测出可能的生日码。通过Python的模块化设计方法,在图形用户界面中实现用户输入和结果展示,旨在提醒人们增强在互联网环境中对个人隐私保护的意识。 展开更多
关键词 身份证号码 校验码 生日码 穷举 隐私
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农产品区域品牌价值攀升的主体异质性研究
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作者 徐静 戴婕 姚冠新 《江苏大学学报(社会科学版)》 2026年第1期46-57,共12页
农产品区域品牌价值攀升是农业高质量发展的重要体现,也是推进乡村全面振兴的有效路径。中国40个茶叶区域品牌价值攀升的主体异质性和门槛效应研究结果显示:建设主体增加和农产品区域品牌价值攀升呈现先升后降的倒“U”形关系,建设主体... 农产品区域品牌价值攀升是农业高质量发展的重要体现,也是推进乡村全面振兴的有效路径。中国40个茶叶区域品牌价值攀升的主体异质性和门槛效应研究结果显示:建设主体增加和农产品区域品牌价值攀升呈现先升后降的倒“U”形关系,建设主体的边际效应出现了递减趋势。异质性分析中,行业协会与农产品区域品牌价值攀升呈显著正相关,企业数量与农产品区域品牌价值攀升呈现倒“U”形关系。建设主体与农产品区域品牌价值攀升的倒“U”形关系只在乡村振兴水平较低的地区存在,且该影响在龙头企业较少的地区更加明显,而乡村振兴水平较高的地区两者几乎呈现出单调递增的线性关系。作用机制检验显示,消费潜力和农业产业结构在建设主体影响农产品区域品牌价值攀升作用中发挥部分正向中介效应。调节效应检验显示,农机应用正向调节建设主体对农产品区域品牌价值攀升的促进作用。为进一步提升农产品区域品牌价值,应做到政府支持引导、行业协会监管、企业规范自身三向发力。 展开更多
关键词 农业区域品牌 品牌价值 建设主体 茶叶 机制检验
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上穹窿Check韧带悬吊法矫正先天性上睑下垂 被引量:14
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作者 杨超 唐炜雅 +4 位作者 戴海英 方硕 栗颖利 沈頔 邢新 《中国美容整形外科杂志》 CAS 2016年第5期261-264,共4页
目的探讨应用上穹窿Check韧带悬吊法矫正先天性上睑下垂的临床效果。方法自2013年1月至2015年12月,采用上穹窿Check韧带悬吊法矫正单侧先天性上睑下垂28例。术中按重睑切口线切开皮肤,在眶隔后方显露提上睑肌腱膜,并在睑板中1/3段... 目的探讨应用上穹窿Check韧带悬吊法矫正先天性上睑下垂的临床效果。方法自2013年1月至2015年12月,采用上穹窿Check韧带悬吊法矫正单侧先天性上睑下垂28例。术中按重睑切口线切开皮肤,在眶隔后方显露提上睑肌腱膜,并在睑板中1/3段横行切断提上睑肌腱膜和Mttller’s肌附着直至结膜;沿结膜前面向上分离,显露结膜上穹窿后上方的Check韧带,将该韧带下拉缝合固定于睑板,悬吊矫正上睑下垂。结果术后随访3—24个月,所有患者下垂体征均得到改善,眼睑均在60d内基本自然闭合,无过度矫正及暴露性角膜炎发生。其中,2例患者术后出现结膜脱垂,均在45d内自行恢复。结论采用上穹窿Check韧带悬吊法矫正上睑下垂,其术式操作简单,效果可靠,眼睑运动接近生理状态,适用于矫正不同程度的先天性上睑下垂,值得临床推广应用。 展开更多
关键词 上穹窿 check韧带 先天性上睑下垂
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Arc CHECK在乳腺癌螺旋断层放疗计划剂量验证中的应用 被引量:9
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作者 张晋建 黎静 +7 位作者 文婷 叶柳清 李志强 侯友贤 贾峻嵩 陈静 王彦 钟毓 《中国医学物理学杂志》 CSCD 2015年第2期244-247,共4页
目的:探讨Arc CHECK旋转调强剂量验证系统在乳腺癌螺旋断层放疗(Helical Tomotherapy,HT)计划剂量验证中的应用可行性。方法:将20例乳腺癌HT计划移植到Arc CHECK系统进行调强放射治疗(Intensity Modulated Radiotherapy,IMRT)计划剂量验... 目的:探讨Arc CHECK旋转调强剂量验证系统在乳腺癌螺旋断层放疗(Helical Tomotherapy,HT)计划剂量验证中的应用可行性。方法:将20例乳腺癌HT计划移植到Arc CHECK系统进行调强放射治疗(Intensity Modulated Radiotherapy,IMRT)计划剂量验证,得到的验证结果与HT计划在其模体中计算获得的平面剂量分布进行比较。剂量验证结果分析采用Gamma分析法,并采用多种标准进行评估。结果:20例乳腺癌病例在阈值水平(Threshold,TH)为10%,3%/3 mm、3%/4 mm、3%/5 mm的γ通过率超过90%的病例数分别占总例数的40%、55%、80%;TH水平为15%,3%/3 mm、3%/4 mm、3%/5 mm的γ通过率超过90%的比例分别为40%、55%、85%,TH水平为20%,3%/3 mm、3%/4mm、3%/5 mm的γ通过率超过90%的比例分别为40%、60%、85%。当评估标准为5%/5 mm时,γ通过率超过90%的比例为100%。靶区剂量均匀性指数(HI),瘤床的同步追量,靶区边界内缩至皮缘下及淋巴结情况对γ通过率无影响(P>0.05)。模体中心偏离x负方向大于4 cm的11例病例中,仅有2例验证结果达到3%/3 mm(TH=10),比例为18%;模体中心偏离x正方向大于4 cm的9例病例中,有6例验证结果达到3%/3 mm(TH=10),比例为66.7%。结论:Arc CHECK旋转调强验证系统可用于乳腺癌HT计划剂量验证,有效地简化了HT剂量验证的流程,但验证模体中心与机器等中心偏移关系对验证通过率的影响仍需配合第三方验证系统作进一步研究。 展开更多
关键词 乳腺癌 螺旋断层放射治疗 旋转调强剂量验证 ARC check
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