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An equivalent target plate damage probability calculation mathematics model and damage evaluation method
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作者 Hanshan Li Xiaoqian Zhang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第11期82-103,共22页
Aiming at the requirement of damage testing and evaluation of equivalent target plate based on the explosion of intelligent ammunition, this paper proposes a novel method for damage testing and evaluation method of ci... Aiming at the requirement of damage testing and evaluation of equivalent target plate based on the explosion of intelligent ammunition, this paper proposes a novel method for damage testing and evaluation method of circumferential equivalent target plate. Leveraging the dispersion characteristics parameters of fragment, we establish a calculation model of the fragment power situation and the damage calculation model under the condition of fragment ultimate penetration equivalent target plate. The damage model of equivalent target plate involves the fragment dispersion density, the local perforation damage criterion, the tearing damage model, and the damage probability. We use the camera to obtain the image of the equivalent target plate with fragment perforation, and research the algorithm of fragment distribution position recognition and fragment perforation area calculation method on the equivalent target plate by image processing technology. Based on the obtained parameters of the breakdown position and perforation area of fragments on equivalent target plate, we apply to damage calculation model of equivalent target plate, and calculate the damage probability of each equivalent target plate, and use the combined probabilistic damage calculation method to obtain the damage evaluation results of the circumferential equivalent target plate in an intelligent ammunition explosion experiment. Through an experimental testing, we verify the feasibility and rationality of the proposed damage evaluation method by comparison, the calculation results can reflect the actual damage effect of the equivalent target plate. 展开更多
关键词 target damage evaluation Damage probability FRAGMENTS Equivalent target plate Image processing
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Safety Evaluation of Myricetin and Crude Extract from Myrica rubra Leaves on Non-target Organisms
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作者 李桥 徐静 +2 位作者 张绍勇 张旭 陈安良 《Plant Diseases and Pests》 CAS 2010年第4期46-50,共5页
[ Objective] The study aimed to supply important basis for developing environment-friendly pesticides with myricetin and crude extract of Myrica rubra leaves as effective components. [ Method] According to "Test guid... [ Objective] The study aimed to supply important basis for developing environment-friendly pesticides with myricetin and crude extract of Myrica rubra leaves as effective components. [ Method] According to "Test guidelines for environmental safety evaluation on chemical pesticides", the toxicity of myricetin and crude extract of M. rubra leaves on non-target organisms was determined and the safety evaluation was carried out. [Result] MyriceUn and crude extract of M. rubra leaves had low toxicity on non-target organisms, such as earthworm, silkworm and soil microbes. Myricetin showed low toxicity and the crude extract of M. rubra leaves showed middle toxicity on tadpole. The high-concentration crude extract of M. rubra leaves had some antifeedant effect on silkworm. [ Conclusion] Myricetin and crude extract of M. rubra leaves had low toxicity on non-tar- get organisms in environment and they were relatively safe. 展开更多
关键词 MYRICETIN Crude extract of M. rubra leaves Non-target organisms Safety evaluation
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Using Grey Target Theory for Power Quality Evaluation Based on Power Quality Monitoring Data 被引量:1
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作者 Qiang Yu Xiankai Chen +2 位作者 Xiaoyue Li Chaoqun Zhou Zhichao Li 《Energy Engineering》 EI 2022年第1期359-369,共11页
Smart grid puts forward higher requirements for power quality.Power quality evaluation can provide a decision-making basis for quality improvement.Based on power quality monitoring data,a grey target method is propose... Smart grid puts forward higher requirements for power quality.Power quality evaluation can provide a decision-making basis for quality improvement.Based on power quality monitoring data,a grey target method is proposed for power quality evaluation.The grey target is composed of power quality evaluation standard and power quality monitoring data to be evaluated.Combining with the characteristics of each power quality evaluation index,the target center of the whole grey target system is found.Then,the power quality monitoring data to be evaluated and the power quality standard mode are compared and analyzed to construct the power quality grey correlation difference information space.Finally,the target center coefficient and target degree of power quality are calculated to realize the comprehensive evaluation of power quality,and the evaluation grade of power quality monitoring data to be evaluated is obtained.Compared with the evaluation results of the existing literature,the effectiveness of the proposed method is verified,which shows that grey target theory is reasonable in the comprehensive evaluation of power quality. 展开更多
关键词 Smart grid power quality evaluation grey target theory monitoring data
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Structural integrity evaluation of irradiated LEU targets for the production of molybdenum‑99 using thermo‑mechanical behavior simulation coupled with pressure of fission gas release calculation
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作者 N.Mellel B.Mohammedi +3 位作者 M.Salhi M.Dougdag S.Missaoui S.Hanini 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2022年第12期12-23,共12页
Irradiated low-enriched uranium as target plates is used to produce,via neutron radiation and from the molybdenum-99 fission product,technetium-99m,which is a radio-element widely used for diagnosis in the field of nu... Irradiated low-enriched uranium as target plates is used to produce,via neutron radiation and from the molybdenum-99 fission product,technetium-99m,which is a radio-element widely used for diagnosis in the field of nuclear medicine.The behavior of this type of target must be known to prevent eventual failures during radiation.The present study aims to assess,via prediction,the thermal–mechanical behavior,physical integrity,and geometric stability of targets under neutron radiation in a nuclear reactor.For this purpose,a numerical simulation using a three-dimensional finite element analysis model was performed to determine the thermal expansion and stress distribution in the target cladding.The neutronic calculation results,target material properties,and cooling parameters of the KAERI research group were used as inputs in our developed model.Thermally induced stress and deflection on the target were calculated using Ansys-Fluent codes,and the temperature profiles,as inputs of this calculation,were obtained from a CFD thermal–hydraulic model.The stress generated,induced by the pressure of fission gas release at the interface of the cladding target,was also estimated using the Redlich–Kwong equation of state.The results obtained using the bonded and unbonded target models considering the effect of the radiation heat combined with a fission gas release rate of approximately 3%show that the predicted thermal stress and deflection values satisfy the structural performance requirement and safety design.It can be presumed that the integrity of the target cladding is maintained under these conditions. 展开更多
关键词 Irradiated LEU target Mo-99 production Integrity evaluation Thermo-mechanical analyses Fission gas pressure
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Survey on quantitative evaluations of moving target defense 被引量:1
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作者 Huanruo LI Yunfei GUO +2 位作者 Shumin HUO Guozhen CHENG Wenyan LIU 《网络与信息安全学报》 2018年第9期66-76,共11页
Quantitative evaluations are of great importance in network security decision-making.In recent years,moving target defense(MTD)has appeared to be a promising defense approach that blocks asymmetrical advantage of atta... Quantitative evaluations are of great importance in network security decision-making.In recent years,moving target defense(MTD)has appeared to be a promising defense approach that blocks asymmetrical advantage of attackers and favors the defender-notwithstanding,it has a limited deployment due to its uncertain efficiency and effectiveness in defense.In that case,quantitative metrics and evaluations of MTD are essential to prove its capability and impulse its further research.This article presents a comprehensive survey on state-of-the-art quantitative evaluations.First,taxonomy of MTD techniques is stated according to the software stack model.Then,a concrete review and comparison on existing quantitative evaluations of MTD is presented.Finally,notice-worthy open issues regarding this topic are proposed along with the conclusions of previous studies. 展开更多
关键词 计算机网络 网络管理 应用程序 信息安全
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Searching and Evaluation of Target Corporation in Merger and Acquisition
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作者 赵春彦 谢徐娟 张新 《Journal of Donghua University(English Edition)》 EI CAS 2010年第6期869-872,共4页
In order to analyze the sources of merger and acquisition(M & A)information,and the relationship between the M & A information and the M & A corporation management bureau,the searching and evaluation proce... In order to analyze the sources of merger and acquisition(M & A)information,and the relationship between the M & A information and the M & A corporation management bureau,the searching and evaluation procedure of M & A target was discussed.The standard modes and procedures of finding the sources of the M & A target,examination of the M & A information,depicting on the future of M & A,and evaluation of the M & A target,were brought forward. 展开更多
关键词 corporation M A searching and evaluation of the M A targets standard modes and procedures M A future description
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TOE视角下区域数字贸易发展异质性路径比较分析——基于31个地区的fsQCA方法
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作者 张嘉晖 《物流科技》 2024年第4期34-40,共7页
数字贸易为我国外贸转型提供新业态与新模式,然而区域数字贸易发展却呈现异质性路径。文章基于TOE视角,采用模糊集定性分析方法(fsQCA)探索我国区域数字贸易发展的异质路径、驱动因素及其联动效应。研究发现:区域数字贸易是数字技术进步... 数字贸易为我国外贸转型提供新业态与新模式,然而区域数字贸易发展却呈现异质性路径。文章基于TOE视角,采用模糊集定性分析方法(fsQCA)探索我国区域数字贸易发展的异质路径、驱动因素及其联动效应。研究发现:区域数字贸易是数字技术进步(T)、区域经济组织(O)与发展环境(E)的异质性耦合关系的呈现,单个前因条件不能构成区域数字贸易高水平发展的必要条件。具体表现为4种路径:信息化推动企业组织结构与经济开放发展的耦合;信息化推动企业成长与产业结构优化的耦合;信息化推动产业结构优化与经济开放发展的耦合;政府支持推动产业结构优化与经济开放发展的耦合。区域数字贸易的发展应采用因地制宜的政策,该研究兼具理论与实际价值,不仅丰富了数字经济体制机制的理论探索,也为经济下行下的国际贸易稳定提供对策思路。 展开更多
关键词 数字贸易 toe视角 异质性路径 评价指标体系 fsQCA
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Overall Evaluation of the Control Schemes of Automobile Pollution and Its Multi-Target Decision
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作者 李多松 王淑贞 陈浩 《International Journal of Mining Science and Technology》 SCIE EI 1998年第1期61-65,共5页
Various control schemes of automobile pollution are comprehensively evaluated by using the weighting and feyzzy methods, from which several feasible schemes are selected, and then mulit-target decision is made by usin... Various control schemes of automobile pollution are comprehensively evaluated by using the weighting and feyzzy methods, from which several feasible schemes are selected, and then mulit-target decision is made by using the minimum distance and hierarcby analysis methods, for determining the optimal control methods of automobile pollution. 展开更多
关键词 AUTOMOBILE POLLUTION control SCHEMES overall evaluation MULTI-target DECISION
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Efficient structural seismic performance evaluation method using improved endurance time analysis 被引量:3
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作者 Li Shuang Liu Kun +2 位作者 Liu Xiangyang Zhai Changhai Xie Fengwei 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2019年第4期795-809,共15页
Evaluation of structural performance under seismic excitations from low intensity to high intensity is essential to verify the seismic resistant capacity of a structure, and usually carried out by the incremental dyna... Evaluation of structural performance under seismic excitations from low intensity to high intensity is essential to verify the seismic resistant capacity of a structure, and usually carried out by the incremental dynamic analysis (IDA) method or pushover method. The recently developed endurance time (ET) method is another method that uses dynamic pushover excitations, i.e., endurance time acceleration function, to obtain results similar to those obtained by IDA or pushover methods with low computational cost and acceptable accuracy. This study proposes an improvement on the ET method by considering more restrictions for both the elastic and inelastic response spectra in the generation procedure, and by specifying a target duration. Four reinforced concrete frame structures with 4, 8, 12, and 16 stories are adopted to verify the accuracy of the improved method. Comparison of the results obtained by the proposed method, the ET method and the IDA method shows that the improved method has a higher accuracy than the ET method. For evaluation of structural responses under specifi c ground motion intensity, which is typically required in seismic design codes, the results obtained by the proposed method are compared with fi ve commonly used ground motion selection methods, and shows the proposed method provides acceptable accuracy for engineering applications. 展开更多
关键词 SEISMIC PERFORMANCE evaluation ENDURANCE TIME method INELASTIC response spectra target DURATION
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A Life Evaluation System and its Application to Mining Machinery Equipment
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作者 LIU Hun-ju WANG Yi-liang YANG Zhao-jian 《International Journal of Plant Engineering and Management》 2010年第3期149-156,共8页
Based on analyzing the mining equipment life evaluation theoretical system, the equipment life evaluation target system of the mining machinery is put forward taking the economic life, security life, reliability life ... Based on analyzing the mining equipment life evaluation theoretical system, the equipment life evaluation target system of the mining machinery is put forward taking the economic life, security life, reliability life and technical life as the targets. Then, the structure and model of the mining equipment life evaluation system are established and prepared for the realization of the system theoretically. Taking hydraulic support as the research object, the life evaluation system of hydraulic support is established and practice shows that the life evaluation system is feasible. 展开更多
关键词 mining machinery equipment life evaluation theoretical system target system
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Animal Exercise:A New Evaluation Method
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作者 Yu Qi Chongyang Zhang Hiroyuki Kameda 《Journal of Computer Science Research》 2022年第2期24-30,共7页
At present,Animal Exercise courses rely too much on teachers’subjective ideas in teaching methods and test scores,and there is no set of standards as a benchmark for reference.As a result,students guided by different... At present,Animal Exercise courses rely too much on teachers’subjective ideas in teaching methods and test scores,and there is no set of standards as a benchmark for reference.As a result,students guided by different teachers have an uneven understanding of the Animal Exercise and cannot achieve the expected effect of the course.In this regard,the authors propose a scoring system based on action similarity,which enables teachers to guide students more objectively.The authors created QMonkey,a data set based on the body keys of monkeys in the coco dataset format,which contains 1,428 consecutive images from eight videos.The authors use QMonkey to train a model that recognizes monkey body movements.And the authors propose a new non-standing posture normalization method for motion transfer between monkeys and humans.Finally,the authors utilize motion transfer and structural similarity contrast algorithms to provide a reliable evaluation method for animal exercise courses,eliminating the subjective influence of teachers on scoring and providing experience in the combination of artificial intelligence and drama education. 展开更多
关键词 Motion transfer Animal exercise evaluation method MONKEYS target scale normalization
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Computer Model for Evaluating Multi-Target Tracking Algorithms
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作者 Garret Vo Chiwoo Park 《Open Journal of Modelling and Simulation》 2019年第1期1-18,共18页
Public benchmark datasets have been widely used to evaluate multi-target tracking algorithms. Ideally, the benchmark datasets should include the video scenes of all scenarios that need to be tested. However, a limited... Public benchmark datasets have been widely used to evaluate multi-target tracking algorithms. Ideally, the benchmark datasets should include the video scenes of all scenarios that need to be tested. However, a limited amount of the currently available benchmark datasets does not comprehensively cover all necessary test scenarios. This limits the evaluation of multitarget tracking algorithms with various test scenarios. This paper introduced a computer simulation model that generates benchmark datasets for evaluating multi-target tracking algorithms with the complexity of multitarget tracking scenarios directly controlled by simulation inputs such as target birth and death rates, target movement, the rates of target merges and splits, target appearances, and image noise types and levels. The simulation model generated a simulated video and also provides the ground-truth target tracking for the simulated video, so the evaluation of multitarget tracking algorithms can be easily performed without any manual video annotation process. We demonstrated the use of the proposed simulation model for evaluating tracking-by-detection algorithms and filtering-based tracking algorithms. 展开更多
关键词 Performance evaluation MULTI-target TRACKING COMPUTER Model SIMULATION
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中国石油陆上中-高成熟度页岩油勘探现状、进展与未来思考 被引量:3
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作者 赵喆 白斌 +3 位作者 刘畅 王岚 周海燕 刘羽汐 《石油与天然气地质》 EI CAS CSCD 北大核心 2024年第2期327-340,共14页
中国石油天然气集团公司(简称中国石油)矿权区陆相页岩油地质资源丰富,“十三五”资源评价,中国石油陆上中-高熟页岩油(简称页岩油)地质资源量201×108t,占中国页岩油地质资源总量的71%。鄂尔多斯盆地延长组7段、松辽盆地青山口组... 中国石油天然气集团公司(简称中国石油)矿权区陆相页岩油地质资源丰富,“十三五”资源评价,中国石油陆上中-高熟页岩油(简称页岩油)地质资源量201×108t,占中国页岩油地质资源总量的71%。鄂尔多斯盆地延长组7段、松辽盆地青山口组和准噶尔盆地芦草沟组等重点层系的产量显著增长,中国石油页岩油年产量从2010年的2.5×10^(4)t增至2023年的391.6×10^(4)t,勘探潜力巨大。研究表明:近年来由于陆相不同类型页岩油具有地质特征非均质性强、富集高产因素明显差异的特点,其效益勘探存在地质认识与勘探技术的双重挑战。特别是:(1)夹层型页岩油虽在鄂尔多斯盆地长71+2亚段(延长组7段1+2亚段)实现规模勘探,但勘探靶体钻遇率变化大,深湖区细粒沉积体系研究薄弱,靶体空间展布刻画技术的准确性仍需提升;(2)混积型页岩油地层垂向厚度大、岩性频繁变化、发育多套地质甜点,在柴达木盆地、渤海湾盆地虽然实现了勘探突破,但垂向地质甜点产量差异明显,页岩油高产主控因素不清,主力靶体评价优选技术、方法仍需完善;(3)页岩型页岩油在松辽盆地青山口组实现了古龙页岩油勘探突破,但陆相湖盆不同类型页岩生、排烃差异明显,页岩原位滞留烃特征变化大,地质-工程一体化靶体评价技术、方法仍需深化研究。总体上中国石油页岩油勘探开发仍处于快速推进阶段,未来应:(1)加强淡水湖盆深湖区多类型砂体成因机制研究,实现薄层浊积砂体等夹层型页岩油效益勘探;(2)加强咸化湖盆富碳酸盐混积型页岩油源-储组合评价,优选主体靶体实现混积型页岩油高效勘探;(3)加强淡水、咸化湖盆优质源岩生、排烃差异性评价,优选最佳靶体,实现不同湖盆页岩型页岩油地质-工程一体化精细勘探。 展开更多
关键词 理论技术进展 靶体 甜点评价 勘探现状 勘探规划 陆相页岩油 中国石油
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氦气地质理论认识、资源勘查评价与全产业链一体化评价关键技术 被引量:3
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作者 陶士振 吴义平 +14 位作者 陶小晚 王晓波 王青 陈胜 高建荣 吴晓智 刘申奥艺 宋连腾 陈荣 李谦 杨怡青 陈悦 陈秀艳 陈燕燕 齐雯 《地学前缘》 EI CAS CSCD 北大核心 2024年第1期351-367,共17页
鉴于我国氦气产业链理论技术需求,针对国内外尚无系统的氦气地质理论认识,缺乏针对性的氦气资源评价方法、参数取值标准,缺乏氦气含量综合准确检测、有利富集区优选方法,无成本指标优化体系及全产业链一体化评价方法等卡点和难点,本文... 鉴于我国氦气产业链理论技术需求,针对国内外尚无系统的氦气地质理论认识,缺乏针对性的氦气资源评价方法、参数取值标准,缺乏氦气含量综合准确检测、有利富集区优选方法,无成本指标优化体系及全产业链一体化评价方法等卡点和难点,本文运用地质、地球化学、重磁电震、投资经济等多学科方法及实验技术,集中力量攻克氦气成藏机理、资源评价及资产评价的关键技术瓶颈。研发形成1项地质理论认识和3项关键技术:基于典型富氦气藏解剖、地下流体中“氦-气-水”相平衡及相-势耦合分析,研究提出氦气“水溶相、气容相、游离相”3种主要赋存状态、“集流、渗流、扩散”3种运移机理、“近氦源、邻断裂、低压区、高部位”4项分布富集控制因素,初步建立了基于“优质氦源、高效输导、适宜载体”的氦气“生-运-聚”地质理论认识。针对国内氦气含量检测技术参差不齐、部分准确度差、与国外数据差别大、无针对性的氦气资源评价方法等系列难题,以氦气源及氦气含量为核心,研发氦气含量综合准确检测技术,构建4类10种氦气资源评价方法,解决了氦气资源分级分类评价的技术瓶颈。针对基底氦源分布、岩性识别、通源断裂刻画及含氦储层评价难题,创建了归一化重磁下延方案,研发了基于深度学习的多尺度断裂智能识别技术和不同氦气含量下的气藏声学性质模拟方法,为氦源岩分布预测、通源断裂刻画、含氦储层测井解释评价及预测奠定了基础。通过建立多元控氦的富氦区带与目标优选技术,解决了富氦区带与目标优选难题。针对国内贫氦实际情况,以提氦装置投资和操作成本最小化为目标,采用响应面法建立优化目标与各主要工艺参数的非线性回归模型,建立了氦气全产业链一体化评价技术,初步解决了天然气低成本提氦工艺流程优化的技术需求。研究成果为我国长期、安全、规模利用氦气资源资产提供了有效支撑。 展开更多
关键词 氦气 氦源岩 氦气成藏机理 资源评价 区带目标优选 响应面法 深度学习 回归模型
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面向“双碳”目标人才培养的工业化学课程教学改革探索与实践 被引量:1
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作者 王庆锋 马艳娥 +1 位作者 汪晓男 段成红 《高教学刊》 2024年第19期135-138,共4页
为培养“双碳”目标高等教育紧缺专业人才,过程装备与控制工程专业工业化学课程“教”与“学”的模式需要与时俱进,改变以教师为中心的教学模式,建立以学生为中心的教学模式势在必行。该文针对工业化学课程教学过程中存在的“双碳”目... 为培养“双碳”目标高等教育紧缺专业人才,过程装备与控制工程专业工业化学课程“教”与“学”的模式需要与时俱进,改变以教师为中心的教学模式,建立以学生为中心的教学模式势在必行。该文针对工业化学课程教学过程中存在的“双碳”目标教育内容不足问题,初步探索通过增加绿色工程教育内容、实施项目驱动教学、建设跨学科的工业化学师资队伍和建立与“双碳”目标人才培养相适应的教学评价方法等措施来提高教学质量,并提出“双碳”目标下工业化学课程体系改革建议,为培养“双碳”目标紧缺人才提供参考和应用实践。 展开更多
关键词 “双碳”目标 绿色工程 教学模式 项目驱动教学 教学评价
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贵州红托竹荪和冬荪的品质评价
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作者 董慧 赵晓燕 +3 位作者 李晓贝 鄂恒超 周昌艳 张艳梅 《食品科学》 EI CAS CSCD 北大核心 2024年第20期198-205,共8页
为分析贵州红托竹荪和冬荪的品质差异,本研究采用营养成分精准定量方法分析了红托竹荪和冬荪的34种营养成分,并基于超高效液相色谱-四极杆飞行时间质谱的非靶向代谢组学技术比较了红托竹荪和冬荪的差异代谢物。结果表明,红托竹荪中L-麦... 为分析贵州红托竹荪和冬荪的品质差异,本研究采用营养成分精准定量方法分析了红托竹荪和冬荪的34种营养成分,并基于超高效液相色谱-四极杆飞行时间质谱的非靶向代谢组学技术比较了红托竹荪和冬荪的差异代谢物。结果表明,红托竹荪中L-麦角硫因、麦角甾醇、总膳食纤维、铁含量较高,其蛋白中必需氨基酸含量(342.2 mg/g)更接近联合国粮食及农业组织/世界卫生组织模式值;冬荪中可溶性糖、钙、蛋白质含量较高,其中检出的海藻糖、甘露醇、甘露糖、葡萄糖的总含量(450.8 mg/g)远高于红托竹荪(114.7 mg/g)。利用多元统计分析,从红托竹荪和冬荪代谢物中筛选出388个差异代谢物,主要包括脂质类化合物145个、氨基酸类化合物38个、糖类化合物17个。与红托竹荪相比,冬荪中有126个代谢物下调,262个代谢物上调,主要的差异代谢物是风味前体物质或风味物质,与红托竹荪和冬荪的风味密切相关。本研究较为系统地评价了红托竹荪和冬荪中营养成分和代谢物差异,可为红托竹荪和冬荪的品质分析及功能成分挖掘提供数据基础。 展开更多
关键词 红托竹荪 冬荪 营养成分 品质评价 非靶向代谢组学
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基于性能的通航桥梁抗船撞评估方法及应用研究 被引量:2
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作者 王永祥 贾小龙 孙红兰 《世界桥梁》 北大核心 2024年第1期95-102,共8页
为合理有效地开展通航桥梁抗船撞性能评估,提出基于性能的桥梁抗船撞标准化评估方法。基于现行《公路桥梁抗撞设计规范》(JTG/T 3360-02-2020),从抗撞性能等级确定、设防代表船型确定、船撞力计算、船撞效应计算以及抗撞性能验算等方面... 为合理有效地开展通航桥梁抗船撞性能评估,提出基于性能的桥梁抗船撞标准化评估方法。基于现行《公路桥梁抗撞设计规范》(JTG/T 3360-02-2020),从抗撞性能等级确定、设防代表船型确定、船撞力计算、船撞效应计算以及抗撞性能验算等方面,采用结构性能目标作为评估准则,建立桥梁抗撞性能评估各环节流程的标准化评估方法。以江苏扬中三桥为应用实例,运用该方法进行该桥20号墩抗撞性能评估,结果表明:20号墩桩基顺桥向抗弯性能不满足JX1级要求,其余验算结果满足要求,桥墩抗撞性能综合评估结果为不满足要求。参照评估结果该桥加装了浮动式防撞设施。桥梁抗撞性能评估标准化,可准确高效实现桥梁抗撞性能等级确定、船撞效应计算、抗撞性能验算等预期的评估功能要求。 展开更多
关键词 桥梁工程 船撞桥 现行规范 结构性能目标 抗撞性能 标准化评估方法 工程应用
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使用模拟目标试验框架对脑出血患者是否应停用他汀类药物相关研究的方法学质量评价
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作者 邢晓璇 张晓彤 +1 位作者 董宪喆 张兰 《中国医院用药评价与分析》 2024年第2期207-210,217,共5页
目的:使用模拟目标试验(TTE)框架,对脑出血(ICH)患者是否停用他汀类药物的观察性研究进行方法学质量评价,总结可以避免的常见方法学缺陷,为后续研究设计提供方法学参考。方法:通过文献研究法筛选符合纳入与排除标准的文献,使用TTE框架... 目的:使用模拟目标试验(TTE)框架,对脑出血(ICH)患者是否停用他汀类药物的观察性研究进行方法学质量评价,总结可以避免的常见方法学缺陷,为后续研究设计提供方法学参考。方法:通过文献研究法筛选符合纳入与排除标准的文献,使用TTE框架评价所纳入文献的方法学质量,包括纳入与排除标准、治疗策略、随机分配方法、随访的开始及结束、结局指标、因果对比、统计分析方案等7个方面。结果:共纳入8篇队列研究,将患者分为两组,其中暴露组患者停用他汀类药物,非暴露组患者继续使用他汀类药物。方法学评价存在以下问题,2项研究将基线后的信息作为排除标准;4项研究未具体描述治疗策略;4项研究无模拟随机分配的方法;3项研究的协变量选择没有明确的文献依据;1项研究未描述随访的时间节点;所有研究均未明确指出采用意向性治疗(ITT)分析或符合方案(PP)分析;仅2项研究描述了处理缺失数据的方法,但选择了直接删除有缺失数据的患者。结论:未来ICH后中止他汀类药物对临床预后影响的类似研究应避免使用基线后的信息来定义纳入与排除标准,明确因果推断(理想情况下同时包括ITT和PP分析),并考虑使用文献综述或临床经验进行协变量的筛选(最好使用有向无环图)。 展开更多
关键词 模拟目标试验 脑出血 因果推断 方法学评价
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基于感官评价的橄榄鲜食品质差异代谢组分析
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作者 谢倩 江来 +2 位作者 丁明月 刘玲玲 陈清西 《中国农业科学》 CAS CSCD 北大核心 2024年第2期363-378,共16页
【目的】筛选影响橄榄鲜食品质的关键代谢物,探究橄榄鲜食品质差异的可能代谢机制。【方法】以4个高接换种橄榄品种(系)果实为试验材料,高接砧木为‘惠圆’,采用感官评价进行鲜食品质评价,通过超高效液相色谱-串联质谱(UPLC-MS/MS)联用... 【目的】筛选影响橄榄鲜食品质的关键代谢物,探究橄榄鲜食品质差异的可能代谢机制。【方法】以4个高接换种橄榄品种(系)果实为试验材料,高接砧木为‘惠圆’,采用感官评价进行鲜食品质评价,通过超高效液相色谱-串联质谱(UPLC-MS/MS)联用技术进行代谢物鉴定及KEGG通路分析,探究果实成熟过程的代谢变化。【结果】4个品种(系)橄榄果实鲜食品质的感官评价结果差异显著,‘甜榄1号’‘东山长穗’鲜食品质好,‘惠圆’‘子阳1号’鲜食品质差;4个品种(系)橄榄果实共鉴定到15类651个代谢物,其中初级代谢产物6类277个,次级代谢产物9类365个;基于变量投影重要性与差异倍数筛选出26个影响橄榄鲜食品质的特征差异代谢物,包括氨基酸及其衍生物(6个)、有机酸(2个)、脂质(2个)、酚类化合物(16个),其中酚类化合物包括酚酸(3个)、黄酮(3个)、黄酮醇(2个)、黄烷醇(3个)以及水解单宁(5个),并结合橄榄成熟过程建立了造成鲜食品质差异的代谢网络,鲜食品质好的橄榄在L-天冬酰胺与N,N-二甲基甘氨酸生物合成代谢途径上积累较高,体现在鲜食口感上与回甘度有关;鲜食品质差的橄榄在水解单宁(二酰基诃子酰基葡萄糖、没食子酰没食子酸甲酯、榛子素A)、黄酮醇[桑色素-3-O-木糖苷、槲皮素-3-O-(6′没食子酰)半乳糖苷]、黄烷-3-醇[7-O-没食子酰基特利色黄烷、儿茶素-(7,8-bc)-4α-(3,4-二羟基苯基)-二氢-2-(3H)-酮、儿茶素-(7,8-bc)-4β-(3,4-二羟基苯基)-二氢-2-(3h)-酮]合成途径上积累较高,体现在鲜食口感上与苦涩味有关。【结论】不同橄榄鲜食品质差异与其成熟过程中氨基酸及其衍生物合成途径和水解单宁、黄酮醇、黄烷-3-醇合成途径的积累差异密切相关。 展开更多
关键词 橄榄 感官评价 鲜食品质 广泛靶向代谢组 特征代谢物
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基于实测数据的机动目标探测性能评估研究
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作者 郭雷平 段文博 +5 位作者 郭冰涛 王怡恬 韩琪 蔡鹏程 赵子淳 任冬 《应用光学》 CAS 北大核心 2024年第4期665-672,共8页
基于TTP准则的静目标鉴别性能理论模型评估方法具有环境适应性强、性能预测准确、系统参数优化便利等优点,但此方法对动目标探测性能评估的准确性还需展开进一步研究。为了准确评估动目标的探测性能,文中搭建了靶标运动系统、红外目标... 基于TTP准则的静目标鉴别性能理论模型评估方法具有环境适应性强、性能预测准确、系统参数优化便利等优点,但此方法对动目标探测性能评估的准确性还需展开进一步研究。为了准确评估动目标的探测性能,文中搭建了靶标运动系统、红外目标生成系统和目标采集及储存系统;采用人眼阈值判断实验方法实现不同成像作用距离、不同运动速度、不同靶标尺寸下的目标探测性能评估,获得了目标探测概率性能曲线;结合NVThermIP现场性能评估理论模型,在系统性能参数输入一致时计算目标探测性能。实验结果表明:NVThermIP现场性能预测模型对于动目标探测性能的预测存在一定偏差,在实验测量的目标运动速率范围内,随着目标运动速率的提升,目标更易被探测。实验结果为动目标性能评估理论模型的修正提供了数据支持。 展开更多
关键词 动目标探测性能 NVThermIP理论 人眼阈值判断 性能评估理论模型
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