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Lean Product Development Process with Design Verification Stages in the Value Stream of Automotive Industry 被引量:4
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作者 Fuat Ali Paker 《Journal of Transportation Technologies》 2021年第1期37-60,共24页
In the automotive industry, lean project</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Ver... In the automotive industry, lean project</span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">s</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> and innovation creation come to life by being updated under the control of systematic interdisciplinary process flows. The lean product development process that changes the shell, defined under the light of the variables created by the competitive conditions, is today measured by the value flow efficiency and the global market spread of the final product. Consequently, the lean product development approach, which aims to identify and purify all the wastes that do none value or create value to the system or cause burdens in the new product development process, is shaped by step-by-step approvals in the flow. In the main automotive industry company practices within the scope of the research (3 national, 3 international), the beginning of the concept of lean in design is to define and optimize the steps in the product development process under the value stream map. Therefore, the product function for which the customer has paid for, the function of the new product or the physical structure used to meet the needs in question, the comfort, life, experience, innovations of the scope that constitute the new product concept are planned and verified and implemented in the simplified automotive design stages at the beginning of the lean product development process. In this research, initial automotive design objectives and stages are at the focal point of the innovation and added value creation brought by the concept of </span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">“</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">lean</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">”</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> approach. The research is modelled on the determination of steps that do not create added value together with the points where the flow circuits’ or stems, the process is devalued, the interdisciplinary holistic studies intensify, the information and delay begin and end in the sequential and simultaneous design validation step transition stages, which are examined under the lean approach. As a visual and virtual tool that enables the elaboration of nominal values such as the total duration of the design verification stages and the influence of interdisciplinary stakeholders or the test level of the product design with the new product added, it reveals the value flow or losses. Hence research;from innovation creation and new product design steps, which constitute the initial stages of the lean product development process, to design verification analysis, the efficiency of the automotive company processes within the scope of the research has been measured by comparing using lean automotive design techniques, methods and concepts. 展开更多
关键词 Design Management Design verification Automotive Design Lean Product Development value Stream Automotive Industry
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Analysis of the Process of Extreme Heavy Rainfall in the Cold Lake in Qinghai
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作者 SHI Xiu-yun1,2,LI Sheng-chen3 1.Golmud Meteorological Bureau in Qinghai,Golmud 816000,China 2.Key Laboratory of Disaster Prevention and Mitigation in Qinghai,Xining 810001,China 3.Qinghai Meteorological Observatory,Xining 810001,China 《Meteorological and Environmental Research》 CAS 2011年第10期23-28,共6页
[Objective] The aim was to analyze the process and reason of the extreme heavy rainfall on June 15,2011 in Cold Lake in Qinghai.[Method] The weather,physical field and satellite of one extreme heavy rain in the cold l... [Objective] The aim was to analyze the process and reason of the extreme heavy rainfall on June 15,2011 in Cold Lake in Qinghai.[Method] The weather,physical field and satellite of one extreme heavy rain in the cold lake in Qinghai were expounded.[Result] The formation of the loop 'crooked neck' of high pressure,which on the one hand posed a typical situation in the circulation of heavy precipitation in Qinghai,and on the other hand,formed the southwest,southeast of the two water vapor transport in air,in addition to the small groove from the trough of Lake Balk hash and the split vortex plateau,resulted into the extreme heavy rainfall in Cold Lake.The presence of thermal low pressure 700 hPa was conducive to the accumulation of low energy and low-level moisture transport from the Qinghai region to the south of Qaidam Basin.[Conclusion] The resulting process was mainly due to heavy rain in the lower troposphere convergence,high-level divergence,high humidity areas and a strong vertical upward motion. 展开更多
关键词 Cold Lake Extreme value of heavy rain Physical quantity field DIAGNOSIS China
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Short-Term Financing of Economic Order Quantity (EOQ) Inventory Model With Probabilistic Quality
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作者 Mahmoud Arayssi Noura Yassine 《Journal of Modern Accounting and Auditing》 2014年第7期793-802,共10页
In this paper, the classical economic order quantity (EOQ) inventory model assumption that all items of a certain product received from a supplier are of perfect quality is relaxed. Another basic assumption that the... In this paper, the classical economic order quantity (EOQ) inventory model assumption that all items of a certain product received from a supplier are of perfect quality is relaxed. Another basic assumption that the payment for the items is made at the beginning of the inventory cycle when they are received is also eased. We consider an inventory situation where items received from the supplier are of two types of quality, perfect and imperfect, and a short deferral in payment is allowed. The split between perfect and imperfect quality items is assumed to follow a known probability distribution. Both qualities of items have continuous demands, and items of imperfect quality are sold at a discount. A mathematical model is developed using the net present value of all cash flows involved in the inventory cycle. A numerical method for obtaining the optimal order quantity is presented, and the impact of the short-term financing is analyzed. An example is presented to validate the equations and illustrate the results. 展开更多
关键词 economic order quantity (EOQ) imperfect quality items continuous demand allowed deferred payment net present value financing policies operations planning
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应用GSP筛查新生儿G6PDd的性能验证及cut-off值设定 被引量:2
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作者 魏庆玲 梁睿 +3 位作者 李冬秀 陈伟荣 吴学威 黄湘 《检验医学与临床》 CAS 2022年第14期1926-1929,共4页
目的对全自动荧光免疫分析仪(GSP)检测干血片葡萄糖-6-磷酸脱氢酶(G6PD)的性能进行验证,并初步建立该方法筛查葡萄糖-6-磷酸脱氢酶缺乏症(G6PDd)的cut-off值。方法前期确定验证方案,对试剂盒自带标准品B、D、E 3个浓度的标本,L、H两个... 目的对全自动荧光免疫分析仪(GSP)检测干血片葡萄糖-6-磷酸脱氢酶(G6PD)的性能进行验证,并初步建立该方法筛查葡萄糖-6-磷酸脱氢酶缺乏症(G6PDd)的cut-off值。方法前期确定验证方案,对试剂盒自带标准品B、D、E 3个浓度的标本,L、H两个浓度的质控品及试剂盒自带标准品B、C、D、E、F 5个浓度标本进行GSP系统的精密度、正确度和线性范围的验证。采用GSP和目前临床常规使用的Victor2D 1420型荧光免疫分析仪(半自动荧光免疫分析仪)同步检测2742例新生儿干血片G6PD水平,比较两种仪器结果,并使用百分位数分布及受试者工作特征(ROC)曲线初步建立中山市博爱医院产前诊断中心GSP筛查G6PDd时G6PD水平的cut-off值。结果应用GSP检测G6PD时,批内变异系数分别为2.09%、1.54%和1.90%,总变异系数分别为3.08%、1.72%和2.12%,分别小于厂家声明的3.40%和3.90%;质控浓度L的25份标本的测量总均值与靶值的相对偏差为3.84%,质控浓度H的25份标本的测量总均值与靶值的相对偏差为3.44%;5个浓度标本的检测值和理论值的线性回归方程为Y=1.0082 X+0.0125,决定系数(R^(2))为0.9991,R^(2)>0.995,线性相关性良好。标本总体P_(5)的G6PD水平为20.10 U/dL。两种仪器的一致性良好。结论GSP应用于中山市新生儿G6PD检测中,精密度、准确度、线性范围均达到了厂家声明的检测性能,可常规用于新生儿G6PDd筛查。该中心初步采用的GSP新生儿G6PDd筛查的cut-off值为20.10 U/dL。 展开更多
关键词 葡萄糖-6-磷酸脱氢酶缺乏症 全自动荧光免疫分析仪 性能验证 CUT-ofF值
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Weak Wavefront Solutions of Maxwell’s Equations in Conducting Media 被引量:1
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作者 Michael Grinfeld Pavel Grinfeld 《Journal of Applied Mathematics and Physics》 2022年第1期190-199,共10页
We analyze the propagation of electromagnetic fronts in unbounded electric conductors. Our analysis is based on the Maxwell model of electromagnetism that includes the displacement current and Ohm’s law in its simple... We analyze the propagation of electromagnetic fronts in unbounded electric conductors. Our analysis is based on the Maxwell model of electromagnetism that includes the displacement current and Ohm’s law in its simplest forms. A weak electromagnetic front is a propagating interface at which the electromagnetic field remains continuous while its first- and higher-order derivatives experience finite jump discontinuities. Remarkably, analysis of such fronts can be performed autonomously, <em>i</em>.<em>e</em>. strictly in terms of the quantities defined on the front. This property opens the possibility of establishing exact analytical solutions of the exact Maxwell system along with the evolution of the front. 展开更多
关键词 Electric Current in Conductors Irreversible thermodynamics Alegra verification Boundary value Problems Exact Solution
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CENTER CONDITIONS AND BIFURCATION OF LIMIT CYCLES FOR A CLASS OF FIFTH DEGREE SYSTEMS
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作者 HuangWentao LiuYirong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2004年第2期167-177,共11页
The center conditions and bifurcation of limit cycles for a class of fifth degree systems are investigated.Two recursive formulas to compute singular quantities at infinity and at the origin are given.The first nine ... The center conditions and bifurcation of limit cycles for a class of fifth degree systems are investigated.Two recursive formulas to compute singular quantities at infinity and at the origin are given.The first nine singular point quantities at infinity and first seven singular point quantities at the origin for the system are given in order to get center conditions and study bifurcation of limit cycles.Two fifth degree systems are constructed.One allows the appearance of eight limit cycles in the neighborhood of infinity,which is the first example that a polynomial differential system bifurcates eight limit cycles at infinity.The other perturbs six limit cycles at the origin. 展开更多
关键词 fifth degree system focal value singular point quantity center conditions bifurcation of limit cycles.
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Ecosystem Services Evaluation of Karst New Urban Areas Based on Net Primary Productivity of Guanshanhu District, Guiyang, Guizhou Province, China
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作者 Ou Deng Yiqiu Li +1 位作者 Ruoshuang Li Guangbin Yang 《Open Journal of Ecology》 2022年第6期377-390,共14页
Net Primary Productivity (NPP) is the basis of the material and energy transport calculation in ecosystem studies. NPP directly reflects the production capacity of plant communities under natural conditions. Ecosystem... Net Primary Productivity (NPP) is the basis of the material and energy transport calculation in ecosystem studies. NPP directly reflects the production capacity of plant communities under natural conditions. Ecosystem services are hot topics in the field of ecology. Many studies calculate ecosystem service value based on NPP. Taking Guanshanhu District of Guiyang City, Guizhou Province as the research object, using TM, ETM<sup>+</sup>, Gaofen2 and MOD17A3HGF.006 as data sources, this paper analyzed the change of ecosystem service value based on NPP in 2000, 2010 and 2020. The results showed that the area of forest ecosystem increased during 2000-2010 and decreased during 2010-2020. The artificial surface grew rapidly from 1146.82 hm<sup>2</sup> to 7544.29 hm<sup>2</sup> during 2000-2020. The farmland ecosystem decreased from 13308.29 hm<sup>2</sup> to 6342.33 hm<sup>2</sup> during 2000-2020. With the dynamic changes in ecosystem spatial distribution and component structure, the total NPP in 2000, 2010 and 2020 was 12.58 × 10<sup>4</sup> t, 11.90 × 10<sup>4</sup> t and 11.78 × 10<sup>4</sup> t, respectively, showing a decreasing trend. The total value of natural and semi-natural ecosystems services based on NPP showed an increasing trend, which was ¥ 6.938 × 10<sup>8</sup> in 2000, ¥ 8.052 × 10<sup>8</sup> in 2010 and ¥ 10.306 × 10<sup>8</sup> in 2020 respectively. The ecosystem contributed the most to the ecological service value in 2000 was farmland, but in 2010 and 2020, it was the forest ecosystem. The ecological service value of grassland and wetland was relatively small, while the ratio of the wetland ecological service value displayed a decreasing trend. In the future, it is necessary to establish a strict pretrial system for land use, so as to effectively protect the natural and semi-natural ecosystems and fulfill the growing ecological demands of residents. 展开更多
关键词 KARST Net Primary Productivity (NPP) Ecological Service Physical quantity Ecological Service value Guanshanhu District
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Exploring the complex trade-offs and synergies of global ecosystem services 被引量:3
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作者 Jinnan Wang Wenjun Wu +7 位作者 Meng Yang Yueming Gao Jiacheng Shao Weishan Yang Guoxia Ma Fang Yu Nan Yao Hongqiang Jiang 《Environmental Science and Ecotechnology》 SCIE 2024年第5期141-148,共8页
The trade-off and synergy relationship of ecosystem services is an important topic in the current assessment.The value of each service provided by the ecosystem is substantially affected by human activities,and conver... The trade-off and synergy relationship of ecosystem services is an important topic in the current assessment.The value of each service provided by the ecosystem is substantially affected by human activities,and conversely,its changes will also affect the relevant human decisions.Due to varying tradeoffs among ecosystem services and synergies between them that can either increase or decrease,it is difficult to optimize multiple ecosystem services simultaneously,making it a huge challenge for ecosystem management.This study firstly develops a global Gross Ecosystem Product(GEP)accounting framework.It uses remote sensing data with a spatial resolution of 1 km to estimate the ecosystem services of forests,wetlands,grasslands,deserts,and farmlands in 179 major countries in 2018.The results show that the range of global GEP values is USD 112e197 trillion,with an average value of USD 155 trillion(the constant price),and the ratio of GEP to gross domestic product(GDP)is 1.85.The tradeoffs and the synergies among different ecosystem services in each continent and income group have been further explored.We found a correspondence between the income levels and the synergy among ecosystem services within each nation.Among specific ecosystem services,there are strong synergies between oxygen release,climate regulation,and carbon sequestration services.A trade-off relationship has been observed between flood regulation and other services,such as water conservation and soil retention services in low-income countries.The results will help clarify the roles and the feedback mechanisms between different stakeholders and provide a scientific basis for optimizing ecosystem management and implementing ecological compensation schemes to enhance human well-being. 展开更多
关键词 Ecosystem services Biophysical quantity Monetary value Trade-off SYNERGY
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An Ordering Policy for Deteriorating Items with Time-Dependent Quadratic Demand and Salvage Value under Permissible Delay in Payment 被引量:1
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作者 Trailokyanath Singh Madan Mohan Muduly +2 位作者 Chittaranjan Mallick Rahul Kumar Gupta Hadibandhu Pattanayak 《American Journal of Operations Research》 2019年第5期201-218,共18页
The article deals with an economic order quantity (EOQ) inventory model for deteriorating items in which the supplier provides the purchaser a permissible delay in payment. This is so when deterioration of units in th... The article deals with an economic order quantity (EOQ) inventory model for deteriorating items in which the supplier provides the purchaser a permissible delay in payment. This is so when deterioration of units in the inventory is subject to constant deterioration rate, demand rate is quadratic function of time and salvage value is associated with the deteriorated units. Shortages in the system are not allowed to occur. A mathematical formulation is developed when the supplier offers a permissible delay period to the customers under two circumstances: 1) when delay period is less than the cycle of time;and 2) when delay period is greater than the cycle of time. The method is suitable for the items like state-of-the-art aircrafts, super computers, laptops, android mobiles, seasonal items and machines and their spare parts. A solution procedure algorithm is given for finding the optimal order quantity which minimizes the total cost of an inventory system. The article includes numerical examples to support the effectiveness of the developed model. Finally, sensitivity analysis on some parameters on optimal solution is provided. 展开更多
关键词 Constant Deterioration RATE Deteriorating Items Economic Order quantity Permissible Delay in PAYMENT SALVAGE value TIME-DEPENDENT QUADRATIC DEMAND RATE
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铁道车辆计量器具量值核查探讨 被引量:1
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作者 陈文芳 包磊 《计量与测试技术》 2024年第4期56-58,共3页
在铁路车辆计量管理中,计量器具技术指标的准确性、技术性能的稳定性直接关系着铁路的安全运输安全,因此,需对无法实施量值溯源的计量器具进行量值核查。由于目前未有相关规定,因此,本文提出一些关于如何实施量值核查方法,为工作人员在... 在铁路车辆计量管理中,计量器具技术指标的准确性、技术性能的稳定性直接关系着铁路的安全运输安全,因此,需对无法实施量值溯源的计量器具进行量值核查。由于目前未有相关规定,因此,本文提出一些关于如何实施量值核查方法,为工作人员在进行核查时提供参考。 展开更多
关键词 计量器具 量值核查 探讨
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论齿轮样板
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作者 林虎 石照耀 《仪器仪表学报》 EI CAS CSCD 北大核心 2024年第6期240-255,共16页
齿轮样板是齿轮参数量值的标准实物载体,用于将齿轮国家测量标准所复现的量值传递到各级齿轮测量仪器上,从而实现齿轮测量的准确性和一致性,保证齿轮产品质量。全面概述了齿轮样板起源及其发展历程;详细论述了齿轮样板的种类、结构及特... 齿轮样板是齿轮参数量值的标准实物载体,用于将齿轮国家测量标准所复现的量值传递到各级齿轮测量仪器上,从而实现齿轮测量的准确性和一致性,保证齿轮产品质量。全面概述了齿轮样板起源及其发展历程;详细论述了齿轮样板的种类、结构及特点、齿轮样板的测量技术及装置、齿轮样板的国际比对、未来的发展与展望。齿轮样板迄今已历经九十多年发展,其种类在不断丰富、尺度不断延伸、复杂度不断简化,作为一种“有形”的实物量具,目前仍不可替代。未来随着“无形”的虚拟仿真测量技术发展,对“有形”实物样板的依赖将可以减弱,“无形”的技术将可能成为量值传递的新模式。 展开更多
关键词 齿轮 齿轮样板 齿轮测量 量值传递与溯源 国际比对 虚拟测量
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核电厂安全级数字化仪控系统故障缺省值的验证与确认
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作者 陈杰 靳津 +2 位作者 肖安洪 曾辉 郭文 《仪表技术》 2024年第4期44-48,共5页
安全级数字化仪控系统中故障缺省值的设置对核电厂安全具有至关重要的作用,但其验证与确认的难点在于具体实施时缺乏明确的细则指导。基于IEEE Std 1012,结合对法规标准、缺省值设计原则及以往项目实施经验的分析,同时考虑到漳州核电一... 安全级数字化仪控系统中故障缺省值的设置对核电厂安全具有至关重要的作用,但其验证与确认的难点在于具体实施时缺乏明确的细则指导。基于IEEE Std 1012,结合对法规标准、缺省值设计原则及以往项目实施经验的分析,同时考虑到漳州核电一期项目数字化仪控系统平台及设计开发流程的特点,提出了一套针对安全级数字化仪控系统故障缺省值的验证与确认策略和方法。经过漳州核电一期的实践验证,这套策略和方法能够充分、高效地验证缺省值设计的正确性和完整性,有效缓解了验证与确认过程中缺乏详尽标准、理论及相关成熟经验可借鉴的困境。对于后续核电安全级数字化仪控系统故障缺省值的验证与确认工作,该策略和方法具有一定的参考价值。 展开更多
关键词 数字化仪控系统 安全级 故障缺省值 验证与确认 核电厂
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电机学中的一些“反常”现象及其成因分析
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作者 程小华 《防爆电机》 2024年第3期1-3,共3页
描述了电机学中的一些“反常”现象,分析了这些现象的成因,并用简明的语言进行归纳,为相关领域的研究人员提供一定参考。
关键词 电机 电气量 磁气量 有效值 最大值 负载 电抗 磁场
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产业数字化与中国制造业就业——破局之策还是雪上加霜 被引量:2
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作者 徐学柳 张勤勤 王倩 《大连理工大学学报(社会科学版)》 CSSCI 北大核心 2024年第3期28-38,共11页
产业数字化是驱动制造业拓宽就业渠道、改善就业结构的新引擎。基于行业“就业难”和“用工荒”现状,分析产业数字化对中国制造业就业数量和就业结构(技能结构、性别结构)的影响机制,并从实证的角度进行了检验。研究结果表明:产业数字... 产业数字化是驱动制造业拓宽就业渠道、改善就业结构的新引擎。基于行业“就业难”和“用工荒”现状,分析产业数字化对中国制造业就业数量和就业结构(技能结构、性别结构)的影响机制,并从实证的角度进行了检验。研究结果表明:产业数字化对制造业就业数量和女性就业占比存在显著的正向影响,而对制造业技术人员占比存在抑制作用;通过使用印度产业数字化作为工具变量的内生性检验和使用替换核心解释变量的稳健性检验结果证明了上述影响机制的稳定性。此外,异质性检验表明,3类产业数字化行业对就业数量均存在正向作用,产业数字化基础设施行业、产业数字化交易行业不利于就业技能结构的调整,产业数字化媒体行业不利于就业性别结构的改善;总体产业数字化除对中低技术水平的制造业行业的就业技能结构具有抑制作用外,对高技术水平的制造业行业就业数量、就业结构均具有促进作用。因此,我国应牢牢把握产业数字化这一破局之策,实施差异化的数字化发展战略,加快培育一批具备技术引领和技术示范的高科技数字化行业,促使中国数字经济产业迅猛发展。 展开更多
关键词 产业数字化 就业数量 就业技能结构 就业性别结构 全球价值链
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水土保持生态产品价值实现理论探索
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作者 吴浓娣 夏朋 +2 位作者 杨研 孙嘉 陈琛 《中国水利》 2024年第12期18-22,共5页
水土保持生态产品价值实现具有重要意义。尝试界定水土保持生态产品概念,对产品进行分类,探索构建水土保持生态产品价值核算方法,分析水土保持生态产品价值转化路径,梳理浙江省安吉县石门坑清洁小流域水土保持生态产品价值转化经验,提... 水土保持生态产品价值实现具有重要意义。尝试界定水土保持生态产品概念,对产品进行分类,探索构建水土保持生态产品价值核算方法,分析水土保持生态产品价值转化路径,梳理浙江省安吉县石门坑清洁小流域水土保持生态产品价值转化经验,提出加快推动水土保持生态产品价值实现的对策建议,以期为推动水土保持高质量发展和建设美丽中国提供有益参考。 展开更多
关键词 水土保持生态产品 价值实现 功能量 价值量 核算方法 转化路径
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改进Petri网下异构跨域用户身份验证方法 被引量:1
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作者 刘峰 姜久雷 《现代电子技术》 北大核心 2024年第13期82-86,共5页
在异构跨域用户身份验证时,由于用户身份存在属性特征难以捕捉、状态描述误差大等问题,导致验证精准度较低,为有效解决这一问题,文中提出一种基于改进Petri网的用户身份验证算法。利用改进Petri网反映不同局域网中事物间依赖关系,将异... 在异构跨域用户身份验证时,由于用户身份存在属性特征难以捕捉、状态描述误差大等问题,导致验证精准度较低,为有效解决这一问题,文中提出一种基于改进Petri网的用户身份验证算法。利用改进Petri网反映不同局域网中事物间依赖关系,将异构跨域用户活动模型与Petri网模型转换,采用同步用户的状态变化提取实时状态特征值。通过建立云间身份认证中心,计算用户不同身份代表性词语在一定周期内出现的次数和频率值。提取频率最高的词语,并计算该词语在待验证用户全部代表词语库中的权重值,对比权重值与验证熵值,将得到的验证参数输入到认证中心,输出验证结果。实验结果表明,所提方法在先验节点比例为8%时,验证准确率达到0.9,且召回率和综合指标均在0.6以上,具备一定的抗攻击性,整体实用性能强、利用价值高。 展开更多
关键词 改进Petri网 异构跨域用户 身份验证 云间身份认证中心 验证熵值 状态特征
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自然资源资产核算研究进展与展望
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作者 刘丹妮 贾玲 +1 位作者 沙金霞 邢钰涵 《水利经济》 北大核心 2024年第6期14-24,75,共12页
通过系统梳理土地、矿产、林业、大气和水等5种自然资源资产的基本内涵、确认条件和核算范围,总结了国内外自然资源资产核算体系的形成脉络、基本构成及实践经验;从基本前提、优缺点、适用条件和应用情况等方面对各类自然资源资产核算... 通过系统梳理土地、矿产、林业、大气和水等5种自然资源资产的基本内涵、确认条件和核算范围,总结了国内外自然资源资产核算体系的形成脉络、基本构成及实践经验;从基本前提、优缺点、适用条件和应用情况等方面对各类自然资源资产核算方法进行比对、筛选和解析;从系统整体角度出发,提出了基于主体功能区划分的区域自然资源资产统一核算流程;结合自然资源资产产权制度改革、大数据平台建设和社会价值核算方法等,对自然资源资产核算的未来方向进行展望,为全面客观核算自然资源资产提供参考与借鉴。 展开更多
关键词 自然资源 资产核算 实物量 价值量 综合核算
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公路工程工地试验室仪器检校结果确认方法
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作者 李岩 张玮 +3 位作者 王芮文 欧定福 曹妍 王磊 《黑龙江交通科技》 2024年第3期135-137,142,共4页
计量检定校准是仪器在使用过程中量值溯源的重要方式之一。仪器设备在检定校准后投入使用之前,试验检测人员或仪器使用者需要对检定校准证书进行符合性确认,通过研究检定校准确认的内容、要求、检定校准证书所涵盖的基础信息,给出了在... 计量检定校准是仪器在使用过程中量值溯源的重要方式之一。仪器设备在检定校准后投入使用之前,试验检测人员或仪器使用者需要对检定校准证书进行符合性确认,通过研究检定校准确认的内容、要求、检定校准证书所涵盖的基础信息,给出了在不同情况下仪器设备检定校准确认的基本方法,并根据例证给出了确认的基本步骤,为公路工程工地试验室仪器设备管理提出了有效方法。 展开更多
关键词 工地试验室管理 仪器检定校准 量值溯源 计量确认
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基于电涡流效应的引信过载脉冲幅值调节方法
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作者 武志博 孙传猛 +3 位作者 焦斌 温竞龙 辛泽洲 汪博 《装备环境工程》 CAS 2024年第8期1-8,共8页
目的解决引信及其关键部件抗过载性能测试实验室模拟加载与实际发射差异较大的技术难题。方法在引信被测试件底部粘贴铝贴片,并在冲击锤上缠绕励磁线圈,使其通入交变电流以产生瞬变磁场,在冲击锤靠近引信试件的过程中,铝贴片内的磁通发... 目的解决引信及其关键部件抗过载性能测试实验室模拟加载与实际发射差异较大的技术难题。方法在引信被测试件底部粘贴铝贴片,并在冲击锤上缠绕励磁线圈,使其通入交变电流以产生瞬变磁场,在冲击锤靠近引信试件的过程中,铝贴片内的磁通发生变化,感应产生电涡流。涡流磁场与激励磁场相互作用,产生阻碍二者之间相对运动的电磁力,以此来实现对过载脉冲波形的调节和整定。结果建立了激励线圈积分圆环的数学模型,推导了电涡流阻力的表达式。利用COMSOL Multiphysics软件建立了电涡流缓冲器的动力学模型,对其进行了仿真验证。在输入电流为10000 A时,冲击过载幅值小于10000g,无法满足引信抗过载模拟试验要求;当输入电流为15000 A时,冲击过载幅值为15232.9g;当输入电流为20000 A时,冲击过载达到27222.8g,冲击过载过高,容易造成试件强度失效。因此,选取输入电流为10000~15000 A较为合理。结论该方法能够实现对高g值过载脉冲幅值的可控调节。 展开更多
关键词 引信 电涡流效应 幅值调节 高g值过载 仿真验证 COMSOL
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基于特征图谱及多成分定量的首乌藤饮片与标准汤剂量值传递规律研究 被引量:1
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作者 曹斯琼 陈康梅 +2 位作者 潘礼业 周湘媛 马懿飞 《天然产物研究与开发》 CAS CSCD 北大核心 2024年第6期1022-1031,共10页
本文建立首乌藤的含量测定方法和指纹图谱评价方法,研究首乌藤饮片到标准汤剂的量值传递规律。收集全国主产地和道地产地具有代表性的20批首乌藤药材,按《中国药典》2020年版规定制备成首乌藤饮片,并按《中药配方颗粒质量控制与标准制... 本文建立首乌藤的含量测定方法和指纹图谱评价方法,研究首乌藤饮片到标准汤剂的量值传递规律。收集全国主产地和道地产地具有代表性的20批首乌藤药材,按《中国药典》2020年版规定制备成首乌藤饮片,并按《中药配方颗粒质量控制与标准制定技术要求》制备成首乌藤标准汤剂;采用HPLC建立适用测定含量及指纹图谱方法,以转移率、出膏率及指纹图谱相似度为指标,分析首乌藤饮片到标准汤剂的量值传递规律。结果显示,20批首乌藤标准汤剂出膏率为10.4%~16.1%,均值为12.9%,均位于均值的±30%范围内。除了四川产地的样品外,其余产地首乌藤饮片及其标准汤剂HPLC对照指纹图谱相似度均良好(>0.9),且二者具6个共有峰,并通过对照品指认其中的4个峰分别2,3,5,4-四羟基二苯乙烯-2-O-β-D-葡萄糖苷、大黄素-8-O-β-D-葡萄糖苷、大黄素、大黄素甲醚。四个已知成分的转移率分别为26.58%~53.07%(2,3,5,4-四羟基二苯乙烯-2-O-β-D-葡萄糖苷)、12.37%~42.84%(大黄素-8-O-β-D-葡萄糖苷)、3.83%~18.71%(大黄素)、0.35%~4.13%(大黄素甲醚)。本文建立了首乌藤饮片及其标准汤剂含量测定方法和指纹图谱方法,阐明了二者之间的化学成分的量值传递规律,为首乌藤水提物及其配方颗粒质量控制提供参考。 展开更多
关键词 首乌藤 标准汤剂 转移率 指纹图谱 量值传递
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