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Influence of initial check, information exchange, final accuracy check, reaction information nursing on the psychology of elderly with lung cancer 被引量:1
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作者 Cui Jiang Jing Ma +1 位作者 Wen He Hai-Ying Zhang 《World Journal of Clinical Cases》 SCIE 2024年第4期737-745,共9页
BACKGROUND As one of the fatal diseases with high incidence,lung cancer has seriously endangered public health and safety.Elderly patients usually have poor self-care and are more likely to show a series of psychologi... BACKGROUND As one of the fatal diseases with high incidence,lung cancer has seriously endangered public health and safety.Elderly patients usually have poor self-care and are more likely to show a series of psychological problems.AIM To investigate the effectiveness of the initial check,information exchange,final accuracy check,reaction(IIFAR)information care model on the mental health status of elderly patients with lung cancer.METHODS This study is a single-centre study.We randomly recruited 60 elderly patients with lung cancer who attended our hospital from January 2021 to January 2022.These elderly patients with lung cancer were randomly divided into two groups,with the control group taking the conventional propaganda and education and the observation group taking the IIFAR information care model based on the conventional care protocol.The differences in psychological distress,anxiety and depression,life quality,fatigue,and the locus of control in psychology were compared between these two groups,and the causes of psychological distress were analyzed.RESULTS After the intervention,Distress Thermometer,Hospital Anxiety and Depression Scale(HADS)for anxiety and the HADS for depression,Revised Piper’s Fatigue Scale,and Chance Health Locus of Control scores were lower in the observation group compared to the pre-intervention period in the same group and were significantly lower in the observation group compared to those of the control group(P<0.05).After the intervention,Quality of Life Questionnaire Core 30(QLQ-C30),Internal Health Locus of Control,and Powerful Others Health Locus of Control scores were significantly higher in the observation and the control groups compared to the pre-intervention period in their same group,and QLQ-C30 scores were significantly higher in the observation group compared to those of the control group(P<0.05).CONCLUSION The IIFAR information care model can help elderly patients with lung cancer by reducing their anxiety and depression,psychological distress,and fatigue,improving their tendencies on the locus of control in psychology,and enhancing their life qualities. 展开更多
关键词 Initial check information exchange final accuracy check reaction information care model Lung cancer Mental health
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Computation Tree Logic Model Checking of Multi-Agent Systems Based on Fuzzy Epistemic Interpreted Systems
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作者 Xia Li Zhanyou Ma +3 位作者 Zhibao Mian Ziyuan Liu Ruiqi Huang Nana He 《Computers, Materials & Continua》 SCIE EI 2024年第3期4129-4152,共24页
Model checking is an automated formal verification method to verify whether epistemic multi-agent systems adhere to property specifications.Although there is an extensive literature on qualitative properties such as s... Model checking is an automated formal verification method to verify whether epistemic multi-agent systems adhere to property specifications.Although there is an extensive literature on qualitative properties such as safety and liveness,there is still a lack of quantitative and uncertain property verifications for these systems.In uncertain environments,agents must make judicious decisions based on subjective epistemic.To verify epistemic and measurable properties in multi-agent systems,this paper extends fuzzy computation tree logic by introducing epistemic modalities and proposing a new Fuzzy Computation Tree Logic of Knowledge(FCTLK).We represent fuzzy multi-agent systems as distributed knowledge bases with fuzzy epistemic interpreted systems.In addition,we provide a transformation algorithm from fuzzy epistemic interpreted systems to fuzzy Kripke structures,as well as transformation rules from FCTLK formulas to Fuzzy Computation Tree Logic(FCTL)formulas.Accordingly,we transform the FCTLK model checking problem into the FCTL model checking.This enables the verification of FCTLK formulas by using the fuzzy model checking algorithm of FCTL without additional computational overheads.Finally,we present correctness proofs and complexity analyses of the proposed algorithms.Additionally,we further illustrate the practical application of our approach through an example of a train control system. 展开更多
关键词 Model checking multi-agent systems fuzzy epistemic interpreted systems fuzzy computation tree logic transformation algorithm
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层厚对使用CT/SIM Check模体联合iQA软件检测CT模拟机的影响
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作者 时飞跃 程龙 +3 位作者 王敏 秦伟 赵环宇 魏晓为 《中国医疗设备》 2023年第7期17-22,共6页
目的探讨层厚大小对使用CT/SIM Check模体联合iQA软件检测放疗CT模拟机数据结果的影响。方法对1台西门子Sensation Open CT模拟机,使用6种放疗扫描协议扫描1套CT/SIM Check模体,扫描完成后重建1.5、2、3、4和5 mm共5种层厚的CT图像序列... 目的探讨层厚大小对使用CT/SIM Check模体联合iQA软件检测放疗CT模拟机数据结果的影响。方法对1台西门子Sensation Open CT模拟机,使用6种放疗扫描协议扫描1套CT/SIM Check模体,扫描完成后重建1.5、2、3、4和5 mm共5种层厚的CT图像序列。使用iQA软件对这些CT图像序列进行自动分析并生成报表,对报表上的质控数据结果进行分析和比较。结果通过对报表数据进行分析,得到了6种扫描协议和5种层厚情形下22种参数的质控数据,对5种不同层厚的数据计算得到了相应的四分位数间距值。由数据结果可见,HU均一性和插件4内标准差的数据随层厚的增加而减小;扫描中心纵向坐标的数值随层厚的增加有下降的趋势;线宽比-灵敏度截面的数据随层厚的增加而变大。结论使用CT/SIM Check模体联合iQA软件检测CT模拟机,层厚对HU均一性、插件4内标准差、扫描中心纵向坐标和线宽比-灵敏度截面的质控数据结果有较大影响,对其他参数的数据也有不同程度的影响。本研究为物理师使用CT/SIM Check模体联合iQA软件检测放疗CT模拟机的质控工作,提供了有益的数据参考。 展开更多
关键词 CT模拟机 质控 CT/SIM check模体 iQA软件 层厚
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Dynamic Modeling Framework of Sediment Trapped by Check-Dam Networks:A Case Study of a Typical Watershed on the Chinese Loess Plateau 被引量:1
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作者 Pengcheng Sun Yiping Wu 《Engineering》 SCIE EI CAS CSCD 2023年第8期209-221,共13页
Check-dam construction is an effective and widely used method for sediment trapping in the Yellow River Basin and other places over the world that are prone to severe soil erosion.Quantitative estimations of the dynam... Check-dam construction is an effective and widely used method for sediment trapping in the Yellow River Basin and other places over the world that are prone to severe soil erosion.Quantitative estimations of the dynamic sediment trapped by check dams are necessary for evaluating the effects of check dams and planning the construction of new ones.In this study,we propose a new framework,named soil and water assessment tool(SWAT)–dynamic check dam(DCDam),for modeling the sediment trapped by check dams dynamically,by integrating the widely utilized SWAT model and a newly developed module called DCDam.We then applied this framework to a typical loess watershed,the Yan River Basin,to assess the time-varying effects of check-dam networks over the past 60 years(1957–2016).The DCDam module generated a specific check-dam network to conceptualize the complex connections at each time step(monthly).In addition,the streamflow and sediment load simulated by using the SWAT model were employed to force the sediment routing in the check-dam network.The evaluation results revealed that the SWAT-DCDam framework performed satisfactorily,with an overestimation of 11.50%,in simulating sediment trapped by check dams,when compared with a field survey of the accumulated sediment deposition.For the Yan River Basin,our results indicated that the designed structural parameters of check dams have evolved over the past 60 years,with higher dams(37.14%and 9.22%increase for large dams and medium dams,respectively)but smaller controlled areas(46.03%and 10.56%decrease for large dams and medium dams,respectively)in recent years.Sediment retained by check dams contributed to approximately 15.00%of the total sediment load reduction in the Yan River during 1970–2016.Thus,our developed framework can be a promising tool for evaluating check-dam effects,and this study can provide valuable information and support to decision-making for soil and water conservation and check-dam planning and management. 展开更多
关键词 check dams Dynamic check dam(DCDam) Loess Plateau Sediment trapping SWAT
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Identifying Counterexamples Without Variability in Software Product Line Model Checking 被引量:1
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作者 Ling Ding Hongyan Wan +1 位作者 Luokai Hu Yu Chen 《Computers, Materials & Continua》 SCIE EI 2023年第5期2655-2670,共16页
Product detection based on state abstraction technologies in the software product line(SPL)is more complex when compared to a single system.This variability constitutes a new complexity,and the counterexample may be v... Product detection based on state abstraction technologies in the software product line(SPL)is more complex when compared to a single system.This variability constitutes a new complexity,and the counterexample may be valid for some products but spurious for others.In this paper,we found that spurious products are primarily due to the failure states,which correspond to the spurious counterexamples.The violated products correspond to the real counterexamples.Hence,identifying counterexamples is a critical problem in detecting violated products.In our approach,we obtain the violated products through the genuine counterexamples,which have no failure state,to avoid the tedious computation of identifying spurious products dealt with by the existing algorithm.This can be executed in parallel to improve the efficiency further.Experimental results showthat our approach performswell,varying with the growth of the system scale.By analyzing counterexamples in the abstract model,we observed that spurious products occur in the failure state.The approach helps in identifying whether a counterexample is spurious or genuine.The approach also helps to check whether a failure state exists in the counterexample.The performance evaluation shows that the proposed approach helps significantly in improving the efficiency of abstraction-based SPL model checking. 展开更多
关键词 Software product line model checking parallel algorithm
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Flood risk assessment of check dams in the Wangmaogou watershed on the Loess Plateau of China
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作者 GAO Ze-chao SHI Peng +4 位作者 LI Zhan-bin LI Peng BAI Lu-lu JIA Yi-li CUI Lin-zhou 《Journal of Mountain Science》 SCIE CSCD 2023年第12期3631-3647,共17页
Check dams have been widely used in China’s Loess Plateau region due to their effectiveness in erosion and flood control.However,the safety and stability of the check dam decrease with the operation process,which inc... Check dams have been widely used in China’s Loess Plateau region due to their effectiveness in erosion and flood control.However,the safety and stability of the check dam decrease with the operation process,which increases the probability of dam failure during flood events and threatens local residents’ life and property.Thus,this study simulated flood process of the check dam failure in the Wangmaogou watershed in Yulin City,Shaanxi Province,China,calculated different types of inundation losses based on the flood inundation area within the watershed,and determined the number of key flood protection check dams by classifying the flood risk levels of the check dams.The results showed that 5 dams in the watershed were subject to overtopping during different rainfall return periods,which was related to their flood discharge capacity.Dam failure flood process showed a rapid growth trend followed by slow decrease,and the time of flood peak advanced with increase in the return period.After harmonization of evaluation scales,the magnitude of flood inundation losses can be ranked as:economic losses(212.409 million yuan) > life losses(10.368 million yuan) > ecological losses(6.433 million yuan).The risk value for both individual dams and the whole dam system decreases as the return period increases.The number of key flood protection check dams in the Wangmaogou watershed was 2,3,3,3,4,and 5 for floods with return periods of 10,20,30,50,100,and 200 years,respectively.The results provided a theoretical basis for the safe operation and risk evaluation of check dams in the Loess Plateau Hills watershed. 展开更多
关键词 check dam Return period Flood control risk Dam failure Inundation loss
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Check dam extraction from remote sensing images using deep learning and geospatial analysis:A case study in the Yanhe River Basin of the Loess Plateau,China
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作者 SUN Liquan GUO Huili +4 位作者 CHEN Ziyu YIN Ziming FENG Hao WU Shufang Kadambot H M SIDDIQUE 《Journal of Arid Land》 SCIE CSCD 2023年第1期34-51,共18页
Check dams are widely used on the Loess Plateau in China to control soil and water losses,develop agricultural land,and improve watershed ecology.Detailed information on the number and spatial distribution of check da... Check dams are widely used on the Loess Plateau in China to control soil and water losses,develop agricultural land,and improve watershed ecology.Detailed information on the number and spatial distribution of check dams is critical for quantitatively evaluating hydrological and ecological effects and planning the construction of new dams.Thus,this study developed a check dam detection framework for broad areas from high-resolution remote sensing images using an ensemble approach of deep learning and geospatial analysis.First,we made a sample dataset of check dams using GaoFen-2(GF-2)and Google Earth images.Next,we evaluated five popular deep-learning-based object detectors,including Faster R-CNN,You Only Look Once(version 3)(YOLOv3),Cascade R-CNN,YOLOX,and VarifocalNet(VFNet),to identify the best one for check dam detection.Finally,we analyzed the location characteristics of the check dams and used geographical constraints to optimize the detection results.Precision,recall,average precision at intersection over union(IoU)threshold of 0.50(AP_(50)),IoU threshold of 0.75(AP_(75)),and average value for 10 IoU thresholds ranging from 0.50-0.95 with a 0.05 step(AP_(50-95)),and inference time were used to evaluate model performance.All the five deep learning networks could identify check dams quickly and accurately,with AP_(50-95),AP_(50),and AP_(75)values higher than 60.0%,90.0%,and 70.0%,respectively,except for YOLOv3.The VFNet had the best performance,followed by YOLOX.The proposed framework was tested in the Yanhe River Basin and yielded promising results,with a recall rate of 87.0%for 521 check dams.Furthermore,the geographic analysis deleted about 50%of the false detection boxes,increasing the identification accuracy of check dams from 78.6%to 87.6%.Simultaneously,this framework recognized 568 recently constructed check dams and small check dams not recorded in the known check dam survey datasets.The extraction results will support efficient watershed management and guide future studies on soil erosion in the Loess Plateau. 展开更多
关键词 check dam deep learning geospatial analysis remote sensing Faster R-CNN Loess Plateau
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Sediment sources and their impacts on a check dam-controlled watershed, Loess Plateau, China
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作者 BAI Lu-lu SHI Peng +9 位作者 WANG Wen LI Zhan-bin YU Kun-xia LI Peng CUI Ling-zhou SHEN Rong-jian GUAN Mu-hong DU Xin-chun ZHANG Xun-le CHEN Wen-fu 《Journal of Mountain Science》 SCIE CSCD 2023年第6期1660-1673,共14页
Soil erosion is a major issue in Loess Plateau,China,and quantitative analyses of sediment sources are crucial for soil erosion control.In this study,a combination of flood couplet analysis and composite fingerprint i... Soil erosion is a major issue in Loess Plateau,China,and quantitative analyses of sediment sources are crucial for soil erosion control.In this study,a combination of flood couplet analysis and composite fingerprint identification was used for historical reconstructions of soil erosion in sediment source areas in Loess Plateau.Each flood couplet was constructed based on sediment 137Cs activity,and past soil erosion was calculated using soil bulk density and storage capacity curves.The contribution rates of the sediment sources were calculated using the fingerprinting method,and the amount of erosion in the sediment source areas was estimated.The best fingerprint combination(Cr,Ni,V,and TOC)enabled a 97.2%recognition of sediment sources from 29 flood events(1956–1990)in the Loess Plateau.The contribution rates of gullies,farmland,grassland,and shrubland were 44.89%,26.38%,10.49%,and 18.24%,respectively.These four land use types contributed 1,227,751,512,and 279 tons of sediments,respectively.Re-vegetation decreased soil erosion(1966–1983),whereas deforestation increased soil erosion(1956–1965 and 1984–1990).Rational soil and water conservation measures on slopes and check dam construction in gullies are therefore suggested to mitigate erosion. 展开更多
关键词 check dam Sediment source Soil and water conservation Land use changes Loess Plateau
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Fast clogging problem of open check dams and a new type suggestion:curved footed type open check dam
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作者 ANILAN Tugce AKCALI Emre 《Journal of Mountain Science》 SCIE CSCD 2023年第5期1201-1219,共19页
Driftwood is one of the important physical components in mountainous rivers which causes severe hazards due to the clogging of bridges,culverts,and narrow sections during floods.Therefore,the understanding of driftwoo... Driftwood is one of the important physical components in mountainous rivers which causes severe hazards due to the clogging of bridges,culverts,and narrow sections during floods.Therefore,the understanding of driftwood dynamics and mitigation measures are crucial for managing wood in rivers.Open check dams are the most commonly used engineering measure for preventing driftwood from reaching downstream areas.Nevertheless,these open check dams frequently lose their sediment transport function when they are blocked by sediment and driftwood,especially during major flood events.This paper proposes a new type of open check dam for preventing from clogging.Thus,flume experiments were conducted to examine the influence of different types of open check dams on the characteristics of driftwood deposition.For the model with wood length(LWD)=16.5 cm,wood diameter(D)=15 mm,and wood number(N)=172,the highest trapping efficiency was observed with 90.1%and 87.2%retention rates for the classical debris flow breaker and curved footed open check dams,respectively.Laboratory tests showed that through this proposed design,woody debris blockage in a very short time was prevented from the accumulation of woods beside the dam.In addition to this,most of the sediment passed through the check dam and most of the driftwood got trapped.It can be briefly stated that the geometrical design of the structure plays an important role and can be chosen carefully to optimize trapping efficiency.By designing this type of open check dams in mountain river basins,it may provide a better understanding of the driftwood accumulation and basis for the optimal design of these structures.Further development of the solution proposed in this work can pave the way for designing different types of open check dams for effective flood management. 展开更多
关键词 Debris flow Open check dam DRIFTWOOD Trapping efficiency Sediment transport Flood management Riverflow
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基于IIFAR微信护理结合聚焦干预在急性心肌梗死PCI术后患者中的应用 被引量:2
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作者 蔡丹霞 郭燕 +1 位作者 赵毅 陈士芳 《海南医学》 CAS 2024年第12期1803-1808,共6页
目的探讨基于初始核对-信息交流-准确性核对-反应(IIFAR)微信护理结合聚焦干预在急性心肌梗死(AMI)经皮冠脉介入治疗(PCI)后的应用效果。方法选取2023年1~4月河南科技大学第一附属医院收治的102例AMI患者纳入研究,按随机数表法分为对照... 目的探讨基于初始核对-信息交流-准确性核对-反应(IIFAR)微信护理结合聚焦干预在急性心肌梗死(AMI)经皮冠脉介入治疗(PCI)后的应用效果。方法选取2023年1~4月河南科技大学第一附属医院收治的102例AMI患者纳入研究,按随机数表法分为对照组和观察组各51例。两组患者均接受PCI术治疗,对照组采取常规干预,观察组于此基础上采取基于IIFAR微信护理与聚焦干预相结合的管理模式,干预时间共6个月。干预前和干预2个月、6个月后,比较两组患者的冠心病自我管理行为量表(CSMS)评分、运动自我效能量表(SEE)评分,术后24 h内和干预2个月、6个月后,比较两组患者的心功能[左心室射血分数(LVEF)、左心室舒张末期内径(LVEDD)、左心房内径(LAD)]和运动能力[无氧阈耗氧量(VO2AT)、峰值耗氧量(VO2peak)、6 min步行距离(6MWD)],并比较两组患者的主要不良心血管事件(MACE)发生情况。结果干预2个月和6个月后,两组患者的CSMS和SEE评分均呈逐渐升高趋势,且观察组患者的CSMS、SEE评分明显高于对照组,差异均有统计学意义(P<0.05);干预2个月和6个月后,两组患者的LVEF均呈逐渐升高趋势,而LVEDD、LAD均呈逐渐降低趋势,且观察组患者的LVEF明显高于对照组,LVEDD、LAD明显低于对照组,差异均有统计学意义(P<0.05);干预2个月和6个月后,两组患者的VO2AT、VO2peak、6 MWD均呈逐渐升高趋势,且观察组患者的VO2AT、VO2peak、6 MWD明显高于对照组,差异均有统计学意义(P<0.05);观察组患者的MACE总发生率为5.88%,略低于对照组的13.73%,但差异无统计学意义(P>0.05)。结论基于IIFAR微信护理结合聚焦干预有助于提高AMI PCI术后患者自我效能与自我管理能力,恢复心功能,提高运动能力。 展开更多
关键词 心肌梗死 初始核对-信息交流-准确性核对-反应 聚焦干预 心功能 运动能力 自我管理能力 自我效能 主要不良心血管事件
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Review of Software Model-Checking Techniques for Dealing with Error Detection in Program Codes
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作者 Ednah Olubunmi Aliyu 《Journal of Software Engineering and Applications》 2023年第6期170-192,共23页
Debugging software code has been a challenge for software developers since the early days of computer programming. A simple need, because the world is run by software. So perhaps the biggest engineering challenge is f... Debugging software code has been a challenge for software developers since the early days of computer programming. A simple need, because the world is run by software. So perhaps the biggest engineering challenge is finding ways to make software more reliable. This review provides an overview of techniques developed over time in the field of software model checking to solve the problem of detecting errors in program code. In addition, the challenges posed by this technology are discussed and ways to mitigate them in future research and applications are proposed. A comprehensive examination of the various model verification methods used to detect program code errors is intended to lay the foundation for future research in this area. 展开更多
关键词 Software Model checking Symbolic Execution State Explosion ABSTRACTION Test Case Generations
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Study on Problems and Countermeasures in the Management of Spot Check of Chinese Herbal Pieces
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作者 Cui Yihang Chen Binbin Sun Lihua 《Asian Journal of Social Pharmacy》 2023年第2期107-115,共9页
Objective To provide suggestions for optimizing the sampling management of Chinese herbal pieces and improving the quality Chinese herbal pieces.Methods Logical reasoning method was used to analyze the problems in the... Objective To provide suggestions for optimizing the sampling management of Chinese herbal pieces and improving the quality Chinese herbal pieces.Methods Logical reasoning method was used to analyze the problems in the drug spot check of Chinese herbal pieces based on the data of drug quality published by the National Medical Products Administration from 2013 to 2021,combined with the current provisions and implementation of drug spot check management in China.Results and Conclusion At present,there are some problems in the drug spot check of Chinese herbal pieces,such as fewer varieties of Chinese herbal pieces in the national drug spot check,the unreasonable sampling links,the insufficient territorial management in some areas,and error-prone sample extraction.It is suggested that the actual quantity and overall quality of Chinese herbal pieces should be fully considered in the formulation of sampling plan.Besides,the variety coverage of drug spot check of traditional Chinese medicine should be strengthened.In the planning,the sampling links shall be made as a whole,and the credit rating and distribution of drug production,operation and use units within the jurisdiction shall be fully combined.While strengthening the sampling management at the production end in areas with concentrated industries,regional special drug spot check should be carried out or the administrative forces at the provincial,municipal and county levels should be fully mobilized to avoid local protection.In the assigned tasks,the name of Chinese herbal pieces should be accurately expressed to avoid the sampling errors of Chinese herbal pieces with the same original medicinal materials and different processing methods. 展开更多
关键词 Chinese herbal pieces drug spot check evaluation spot check supervision spot check
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CRC校验码软件生成技术原理分析 被引量:1
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作者 罗长洲 马梦宇 +1 位作者 李萌 李泽超 《计算机仿真》 2024年第3期158-161,481,共5页
循环冗余校验(Cyclic Redundancy Check,CRC)具有检错能力强,运算简单,易于直接用硬件数字电路实现的特点。在完善CRC校验码生成原理模型的基础上,研究了信息系统传输带CRC校验码数据包的一般过程,提出了三种计算数据包CRC校验码的技术... 循环冗余校验(Cyclic Redundancy Check,CRC)具有检错能力强,运算简单,易于直接用硬件数字电路实现的特点。在完善CRC校验码生成原理模型的基础上,研究了信息系统传输带CRC校验码数据包的一般过程,提出了三种计算数据包CRC校验码的技术方法,在ADI公司DSP软件集成开发仿真测试环境中,设计了一组嵌入式程序,生成了符合ITU组织CRC16 ITU-T V.41标准的CRC校验码码表,分析并总结了CRC校验码码表元素的工程含义和应用方法,研究了两种计算数据包CRC校验码工程实现方法的技术特点,并验证了它们的正确性、一致性和有效性。 展开更多
关键词 信息系统 循环冗余校验 循环冗余码 多项式
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国家安全战略视域下的美国对华制度制衡及影响 被引量:3
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作者 夏立平 《亚太安全与海洋研究》 CSSCI 北大核心 2024年第2期36-52,I0002,I0003,共19页
形成于21世纪初的制度制衡理论,实际上已成为后冷战时期美国外交政策特别是对华政策的主导理论之一。从美国国家安全战略的角度,可以发现自2001年以来美国历届政府制约中国的因素不断上升,其对华实施的制度制衡方略经历了从包容性向排... 形成于21世纪初的制度制衡理论,实际上已成为后冷战时期美国外交政策特别是对华政策的主导理论之一。从美国国家安全战略的角度,可以发现自2001年以来美国历届政府制约中国的因素不断上升,其对华实施的制度制衡方略经历了从包容性向排他性的转变。小布什政府采用试图将中国纳入美国主导的国际体系的包容性制度制衡方略,奥巴马政府则采用两面下注的混合型对华包容性制度制衡方略。特朗普政府主要利用美国国内法律和制度对华进行排他性制度制衡,而拜登政府采用“小圈子”对华进行排他性制度制衡。拜登政府在高科技领域对华实行制度制衡,企图在某种程度上迟滞中国高科技发展,客观上却促使中国自立自强形成尽可能完整的高科技生产链,对美国自身高科技产业和国内经济也产生“反噬”效应,无法从根本上改变经济全球化大趋势。 展开更多
关键词 美国 国家安全战略 制度制衡 拜登政府 对华政策
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基于BIM和知识图谱的自动审查方法
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作者 龙丹冰 雷昕 +2 位作者 王初翀 方长建 康永君 《土木建筑工程信息技术》 2024年第2期29-33,共5页
本文在设计合规性审查中引入知识图谱技术,提出以规范知识图谱为核心的自动审查系统。通过对中国规范及结构设计规则(以下统称为规范)分析,提出面向规范最小语义单元的规范知识图谱元结构,建立了反映建筑规范复杂语义逻辑元结构的链接规... 本文在设计合规性审查中引入知识图谱技术,提出以规范知识图谱为核心的自动审查系统。通过对中国规范及结构设计规则(以下统称为规范)分析,提出面向规范最小语义单元的规范知识图谱元结构,建立了反映建筑规范复杂语义逻辑元结构的链接规则,进而以元结构为基元提出了规范知识图谱的构建方法。通过从图谱中获取数据,驱动代码生成模块自动生成用于信息检索和审查的可执行规范审查代码,可实现BIM模型的自动审查。 展开更多
关键词 知识图谱 合理性审查 自动审查 BIM模型
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股权结构对制造业企业绿色创新的影响研究 被引量:1
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作者 程晓多 张立彤 杨博文 《管理现代化》 北大核心 2024年第2期136-146,共11页
以2007-2022年A股制造业上市公司数据,实证检验了股权结构对企业绿色创新的影响及其机制。研究结果表明,股权集中度与企业绿色创新负相关,而股权制衡度与企业绿色创新正相关。机制分析表明,股权集中度以降低数字化转型水平阻滞企业绿色... 以2007-2022年A股制造业上市公司数据,实证检验了股权结构对企业绿色创新的影响及其机制。研究结果表明,股权集中度与企业绿色创新负相关,而股权制衡度与企业绿色创新正相关。机制分析表明,股权集中度以降低数字化转型水平阻滞企业绿色创新,融资约束在股权集中度与企业绿色创新之间发挥了遮掩效应;股权制衡度通过缓解企业融资约束、提高数字化转型程度促进企业绿色创新。另外,异质性分析发现,股权集中度与企业绿色创新的负相关性在国有企业和非重污染企业中更强;股权制衡度与企业绿色创新的正相关性在非国有企业、中小型企业和非重污染企业中更为显著。 展开更多
关键词 股权集中度 股权制衡度 融资约束 数字化转型 绿色创新
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BIM模型编码可变性检验与自动匹配方法研究 被引量:1
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作者 陈建兰 朱晟熙 顾云凡 《建筑技术》 2024年第6期764-768,共5页
为解决BIM元素变更导致的Web-BIM系统数据库与BIM元素无法匹配的问题,本研究首先根据各类BIM文件的特点,选择Rvt文件作为编辑BIM文件,选择Gltf文件作为Web端加载文件。对BIM模型的编码可变性进行了验证,结果表明对BIM构件尺寸修改、属... 为解决BIM元素变更导致的Web-BIM系统数据库与BIM元素无法匹配的问题,本研究首先根据各类BIM文件的特点,选择Rvt文件作为编辑BIM文件,选择Gltf文件作为Web端加载文件。对BIM模型的编码可变性进行了验证,结果表明对BIM构件尺寸修改、属性修改、位置移动等操作均不会改变构件的编码;若对BIM构件进行删除,该构件会被赋予新的编码,但其他构件的编码均不会被影响。本研究提出一种BIM模型变更前后自动匹配方法,通过建立元素识别和跟踪数据库、元素匹配算法、用户交互及确认、更新质量信息、定期检查等步骤,可以实现BIM模型变更前后Web端与BIM元素的匹配,为建筑项目的管理提供了有力的工具。 展开更多
关键词 BIM模型 编码变更 可变性检验 自动匹配 Web-BIM
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基于Q-checker的直升机MBD模型质量自动检查应用研究
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作者 崔立志 《中国科技纵横》 2023年第20期51-53,共3页
从模型质量控制重要性入手,在现有MBD模型质量控制手段的基础上,对模型质量检查工具Q-check与审签系统相结合的质量控制应用方式进行研究。加强模型质量把控,严禁未通过模型质量检查、不符合模型质量标准的MBD模型通过审签系统审签,以... 从模型质量控制重要性入手,在现有MBD模型质量控制手段的基础上,对模型质量检查工具Q-check与审签系统相结合的质量控制应用方式进行研究。加强模型质量把控,严禁未通过模型质量检查、不符合模型质量标准的MBD模型通过审签系统审签,以达到提高生产效率的目的。 展开更多
关键词 MBD Q-check 模型质量控制
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基于特斯拉阀的黏滞阻尼器减震性能研究
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作者 孙彤 赵广晋 +1 位作者 张皓 孙丽 《世界地震工程》 北大核心 2024年第3期167-175,共9页
针对一种基于特斯拉阀单向流通性的新型黏滞阻尼器,利用MTS landmark电液伺服试验系统对单双阀两种工况的阻尼器进行多振幅多频率循环加载;基于流体在特斯拉阀内的沿程损失建立理论模型,用MATLAB软件对新型阻尼器及传统孔隙式黏滞阻尼... 针对一种基于特斯拉阀单向流通性的新型黏滞阻尼器,利用MTS landmark电液伺服试验系统对单双阀两种工况的阻尼器进行多振幅多频率循环加载;基于流体在特斯拉阀内的沿程损失建立理论模型,用MATLAB软件对新型阻尼器及传统孔隙式黏滞阻尼器进行仿真分析,分组讨论新型阻尼器的耗能减震性能。试验及仿真结果表明:新型阻尼器是一种无刚度的速度相关型阻尼器,试验值与仿真值基本吻合,较传统阻尼器减震性能突出;单阀阻尼器其性能受流体速度影响存在适用局限性,可通过调整阀门组数以调节阻尼器耗能性能。 展开更多
关键词 黏滞阻尼器 特斯拉阀 单向阀 耗能 MTS
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基于Kriging插值代理模型的轴流式止回阀多目标优化 被引量:1
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作者 张立强 刘岱阳 《机床与液压》 北大核心 2024年第1期168-175,共8页
基于Kriging插值代理模型,对轴流式止回阀的各项性能进行综合优化,具体的优化目标为:降低正向流阻;减小阀芯振动;提升止回性能。通过试验设计方案找到影响轴流式止回阀正向流阻的主要结构参数因素,并以其作为优化对象,通过Kriging插值... 基于Kriging插值代理模型,对轴流式止回阀的各项性能进行综合优化,具体的优化目标为:降低正向流阻;减小阀芯振动;提升止回性能。通过试验设计方案找到影响轴流式止回阀正向流阻的主要结构参数因素,并以其作为优化对象,通过Kriging插值法拟合主要结构参数对应的性能样本点,在保证拟合精度的情况下,使用NSGA-II遗传算法同时对3个主要结构参数进行多目标优化,得到了三目标Pareto前沿,经过权衡不同因素对性能指标的影响大小,最终得到了综合性能最优的结构参数为:阀瓣丰满度系数α_(1)=2.199,阀芯长度L=386.322 mm,阀芯半径R=113.997 mm。其对应的止回阀性能为:正向出口流量Q=161.839 kg/s,正向出口流速v=3.30235 m/s,止回阀进口压力p=97632.2287 Pa。相比优化之前,阀门正向流阻减小了1.2%,阀芯振动降低了0.24%,止回性能提升了2.3%。 展开更多
关键词 轴流式止回阀 多目标优化 试验设计 Kriging插值模型
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