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Methods for Industrial Measurement and Basic Principles of Their Choices
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作者 FENG Wenhao 《Geo-Spatial Information Science》 2002年第2期28-36,共9页
In this paper,a variety of industrial objects are systematically analyzed.Ten methods for industrial measurement are summarized.For each method,its nature,advantages,disadvantages and adaptability are briefly given.Th... In this paper,a variety of industrial objects are systematically analyzed.Ten methods for industrial measurement are summarized.For each method,its nature,advantages,disadvantages and adaptability are briefly given.The basic principles to choose the right industrial method are indicated. 展开更多
关键词 系统分析 工业测量法 选择测法原则 GPS法
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A LARGE DEVIATION PRINCIPLE FOR THE STOCHASTIC GENERALIZED GINZBURG-LANDAU EQUATION DRIVEN BY JUMP NOISE
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作者 王冉 张贝贝 《Acta Mathematica Scientia》 SCIE CSCD 2023年第2期505-530,共26页
In this paper,we establish a large deviation principle for the stochastic generalized Ginzburg-Landau equation driven by jump noise.The main difficulties come from the highly non-linear coefficient and the jump noise.... In this paper,we establish a large deviation principle for the stochastic generalized Ginzburg-Landau equation driven by jump noise.The main difficulties come from the highly non-linear coefficient and the jump noise.Here,we adopt a new sufficient condition for the weak convergence criterion of the large deviation principle,which was initially proposed by Matoussi,Sabbagh and Zhang(2021). 展开更多
关键词 large deviation principle weak convergence method stochastic generalized Ginzburg-Landau equation Poisson random measure
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Pareto-Optimal Reinsurance Based on TVaR Premium Principle and Vajda Condition
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作者 Fengzhu Chang Ying Fang 《Open Journal of Applied Sciences》 2023年第10期1649-1680,共32页
Reinsurance is an effective risk management tool for insurers to stabilize their profitability. In a typical reinsurance treaty, an insurer cedes part of the loss to a reinsurer. As the insurer faces an increasing num... Reinsurance is an effective risk management tool for insurers to stabilize their profitability. In a typical reinsurance treaty, an insurer cedes part of the loss to a reinsurer. As the insurer faces an increasing number of total losses in the insurance market, the insurer might expect the reinsurer to bear an increasing proportion of the total loss, that is the insurer might expect the reinsurer to pay an increasing proportion of the total claim amount when he faces an increasing number of total claims in the insurance market. Motivated by this, we study the optimal reinsurance problem under the Vajda condition. To prevent moral hazard and reflect the spirit of reinsurance, we assume that the retained loss function is increasing and the ceded loss function satisfies the Vajda condition. We derive the explicit expression of the optimal reinsurance under the TVaR risk measure and TVaR premium principle from the perspective of both an insurer and a reinsurer. Our results show that the explicit expression of the optimal reinsurance is in the form of two or three interconnected line segments. Under an additional mild constraint, we get the optimal parameters and find the optimal reinsurance strategy is full reinsurance, no reinsurance, stop loss reinsurance, or quota-share reinsurance. Finally, we gave an example to analyze the impact of the weighting factor on optimal reinsurance. 展开更多
关键词 Pareto-Optimal Reinsurance TVaR Risk measure Vajda Condition TVaR Premium principle
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CHARACTERISTIC GRAIN SIZE: PART Ⅱ MEASURING PRINCIPLES
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作者 Cao Shunhua (Powder Metallurgy National Key Laboratory, Central South University of Technology, Changsha 410083, China)David C Lam(Department of Mechanical Engineering,The Hongkong University of Science & Technology Clear Water Bay,Kowloon,Hongkong) 《Journal of Central South University》 SCIE EI CAS 1997年第2期117-119,共3页
The principles for measuring characteristic grain sizes of materials, such as fully-dense single phase materials, porous materials and materials with isolated second phase particles, are developed on the basis of its ... The principles for measuring characteristic grain sizes of materials, such as fully-dense single phase materials, porous materials and materials with isolated second phase particles, are developed on the basis of its definition associated closely with the surface area per unit volume, Sv, of grain. The focus of the measuring principles of the characteristic grain size is put on determining Sv of grains. Unlike the measurement of average grain size commonly used, G, correcting factors such as grain shape and grain size distribution factors, will not be applied to the determination of the characteristic grain size, Gc, due to its unique geometric meaning and the measure precision of Sv being guaranteed by quantitative stereological technique and gas adsorption method. The measurement of Gc can be directly carried out on the polished and etched cross section of materials, similar to the measuremernt of the average grain size using the Heyn intercept method. 展开更多
关键词 CHARACTERISTIC GRAIN size measurING principle gas adsorption technique porous MATERIAL fullydense single phase materials MATERIAL with isolated second-phase particles
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The Principle of Proportionality Toward Risk Prevention——Based on the Judgment Logic of European COVID-19 Derogation Measures
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作者 范继增 王瑜鸿 JIANG Yu(Translated) 《The Journal of Human Rights》 2021年第4期598-619,共22页
The COVID-19 pandemic has brought legal challenges to the containment measures adopted by European countries.During the outbreak and containment phase of the pandemic,most European countries adopted measures such as l... The COVID-19 pandemic has brought legal challenges to the containment measures adopted by European countries.During the outbreak and containment phase of the pandemic,most European countries adopted measures such as lockdowns and mandatory home quarantines based on the principle of risk prevention.However,Article 15 of the European Convention on Human Rights and judgments by the European Court of Human Rights require such measures to comply with the principle of proportionality.In view of this,this article examines the European Court of Justice’s loose judgments on the derogation measures during the pandemic,and the European Court of Human Rights’situational judgments in this regard.Based on the analysis of the legitimacy of the principle of risk prevention and the principle of proportionality in responding to public health emergencies,this article prudently examines and predicts the trend of applying the principle of proportionality of risk prevention for the European COVID-19 derogation measures from three perspectives of legitimacy,necessity,and feasibility. 展开更多
关键词 COVID-19 derogation measures the principle of risk prevention the principle of proportionality the principle of proportionality of risk prevention
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A simplified approach to the basic principle of security measures onboard ships
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《交通建设与管理》 2004年第5期22-24,共3页
There are many reasons whymerchant ships make desirable targetsfor pirates and terrorists as well as aconvenient means of transport for thestowaway. Criminal activity in the form ofsuch threats is quickly becoming one... There are many reasons whymerchant ships make desirable targetsfor pirates and terrorists as well as aconvenient means of transport for thestowaway. Criminal activity in the form ofsuch threats is quickly becoming one ofthe greatest threats to ships and 展开更多
关键词 A simplified approach to the basic principle of security measures onboard ships
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A MAXIMUM PRINCIPLE FOR DISTRIBUTED PARAMETER SYSTEMS WITH MIXED PHASE-CONTROL CONSTRAINTS ANDENDPOINT CONSTRAINTS
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作者 张平健 《Acta Mathematica Scientia》 SCIE CSCD 1997年第2期151-158,共8页
This paper considered the optimal control problem for distributed parameter systems with mixed phase-control constraints and end-point constraints. Pontryagin's maximum principle for optimal control are derived vi... This paper considered the optimal control problem for distributed parameter systems with mixed phase-control constraints and end-point constraints. Pontryagin's maximum principle for optimal control are derived via Duboviskij-Milujin theorem. 展开更多
关键词 maximum principle distributed parameter systems end-point constraints Duboviskij-Milujin theorem additive vector measure
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A METHOD OF ON-LINE MEASUREMENT FOR THE FREQUENCY RESPONSE AND IMPULSE RESPONSE FUNCTIONS OF MULTIVARIATE SYSTEM
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作者 汪凤泉 韩晓林 吴慧新 《Journal of Southeast University(English Edition)》 EI CAS 1993年第1期95-101,共7页
In this paper,a method of multipoint pseudorandom combined excita-tion with the orthogonal reciprocal repeated sequences(ORRS)is presented on thebackground of the on-line identification of multivariate system.The capa... In this paper,a method of multipoint pseudorandom combined excita-tion with the orthogonal reciprocal repeated sequences(ORRS)is presented on thebackground of the on-line identification of multivariate system.The capacity of therestraint to the identification error caused by the non-random D.C.drift of the mul-ti-input excitation with the ORRS in the multivariate system is also discussed.Thevalidity of the method described in this paper is proved by the modelling tests of themulti-plate rotor system. 展开更多
关键词 ON-LINE IDENTIFICATION multi-point EXCITATION ORTHOGONAL reciprocal repeated SEQUENCE VIBRATION measurement
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OPTIMAL REINSURANCE UNDER EXPECTED VALUE PRINCIPLE
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作者 Cao Yusong Zhang Yi 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2006年第4期454-460,共7页
The paper concerns the problem how to purchase the reinsurance in order to make the insurer and the reinsurance company's total risk to be least under the expected value principle. When the insurer and reinsurance co... The paper concerns the problem how to purchase the reinsurance in order to make the insurer and the reinsurance company's total risk to be least under the expected value principle. When the insurer and reinsurance company take arbitrary risk measures, sufficient con- ditions for optimality of reinsurance contract are given within the restricted class of admissible contracts. Further, the explicit forms of optimal reinsurance contract under several special risk measures are given, and the method to decide parameters as well. 展开更多
关键词 REINSURANCE expected value principle variance risk measure Lagrangian function.
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Statistical Mechanics for Weak Measurements and Quantum Inseparability
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作者 Salwa Al Saleh 《Journal of Quantum Information Science》 2016年第1期10-15,共6页
In weak measurement thought experiment, an ensemble consists of M quantum particles and N states. We observe that separability of the particles is lost, and hence we have fuzzy occupation numbers for the particles in ... In weak measurement thought experiment, an ensemble consists of M quantum particles and N states. We observe that separability of the particles is lost, and hence we have fuzzy occupation numbers for the particles in the ensemble. Without sharply measuring each particle state, quantum interferences add extra possible configurations of the ensemble, this explains the Quantum Pigeonhole Principle. This principle adds more entropy to the system;hence the particles seem to have a new kind of correlations emergent from particles not having a single, well-defined state. We formulated the Quantum Pigeonhole Principle in the language of abstract Hilbert spaces, then generalized it to systems consisting of mixed states. This insight into the fundamentals of quantum statistical mechanics could help us understand the interpretation of quantum mechanics more deeply, and possibly have implication on quantum computing and information theory. 展开更多
关键词 Quantum Computing Copenhagen Interpretation Quantum Pigeonhole principle Quantum Correlation Information Theory Quantum Statistical Mechanics Weak measurement Quantum measurement Post Selection
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测控一体式分水农门试验与水力特性探索
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作者 刘鸿涛 李晓军 +4 位作者 周双 李锦锦 赵瑞娟 赵虎 张福军 《灌溉排水学报》 CAS CSCD 2024年第2期25-30,共6页
【目的】设计一种一体式量控建筑物—测控一体式分水农门,探究其在梯形渠道上的量水性能。【方法】利用农门控制碟阀和圆管组合而成测控一体式分水农门(以下简称分水农门),研究不同流量Q、不同农门控制碟阀开度θ下的分水农门各项水力... 【目的】设计一种一体式量控建筑物—测控一体式分水农门,探究其在梯形渠道上的量水性能。【方法】利用农门控制碟阀和圆管组合而成测控一体式分水农门(以下简称分水农门),研究不同流量Q、不同农门控制碟阀开度θ下的分水农门各项水力特性以及流量公式。【结果】(1)通过拟合设计分水农门流量公式计算出的流量与实测流量平均误差为4.34%,流量量测误差小于±5%,满足灌区量水精度要求。(2)分水农门中输水管道部分“最优测点”位于管道整体长度0.475~0.575处。(3)分水农门主要是在水流经过碟阀时产生局部水头损失和沿程水头损失,水头损失介于29.54%~38.89%。【结论】当流量在30~65m^(3)/h时,不同流量工况和碟阀开度下分水农门满足灌区量水精度要求,可在灌区末级渠道进行水量计量。 展开更多
关键词 量水设施 灌区量水 测流原理 水力特性
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基于红外摄像装置的Triniti呼吸门控系统的设计和性能验证
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作者 刘颖 王鑫 +2 位作者 徐瑶瑶 袁玲 潘宇龙 《中国医疗设备》 2024年第4期35-40,共6页
目的通过分析红外摄像装置Triniti呼吸门控系统和腹压带方式下采集的呼吸运动波形及4DCT影像一致性,验证Triniti呼吸门控系统的临床可行性。方法利用CIRS 18023-A呼吸运动模体及配套的CIRS Motion Control软件,导入仿真标准呼吸运动及... 目的通过分析红外摄像装置Triniti呼吸门控系统和腹压带方式下采集的呼吸运动波形及4DCT影像一致性,验证Triniti呼吸门控系统的临床可行性。方法利用CIRS 18023-A呼吸运动模体及配套的CIRS Motion Control软件,导入仿真标准呼吸运动及真实患者的呼吸运动曲线,模拟人体肺部呼吸运动的周期、幅度、频率等,产生不同的呼吸运动模型,并分别用基于腹压带和Triniti呼吸门控系统2种呼吸运动信号触发CT扫描,分析2种装置触发下的4DCT影像一致性,最后根据Triniti系统追踪的呼吸运动,设置门控范围,实现门控治疗。结果2种呼吸运动信号探测装置采集到的呼吸运动波形曲线相关性>0.8(P<0.001),4DCT影像各时相感兴趣区域测量度差异性值为(0.065±0.069)cm,差异无统计学意义(P>0.05)。结论基于红外摄像装置的Triniti呼吸门控系统追踪呼吸精度高,可实现临床呼吸门控治疗,从而有效减少呼吸运动对放射治疗造成的影响。 展开更多
关键词 红外摄像原理 呼吸门控 4DCT 系统设计 门控延迟测量
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学科基础课测量原理课程思政探索与实践 被引量:1
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作者 胡梅 周超 +1 位作者 郭熙业 王光明 《高教学刊》 2024年第6期181-184,共4页
测量原理是国防科技大学仪器科学与技术学科测控技术与仪器专业的一门学科基础必修课程,其中蕴含着丰富的认识论和方法论等思政元素,具有天然的思政属性。以立德树人为出发点,从国家整体发展战略、专业人才培养目标、科学共同体的精神... 测量原理是国防科技大学仪器科学与技术学科测控技术与仪器专业的一门学科基础必修课程,其中蕴含着丰富的认识论和方法论等思政元素,具有天然的思政属性。以立德树人为出发点,从国家整体发展战略、专业人才培养目标、科学共同体的精神三个维度进行课程思政教学整体设计,梳理课程内容知识单元的思政要素切入点,有针对性地设计典型的思政案例。结合星间链路关键技术及其北斗工程应用思政案例,进行教学实践,取得良好的教学效果,达到课程思政的育人目标。 展开更多
关键词 测量原理 课程思政 专业人才培养 科学共同体 立德树人
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本科量子物理实验课程探索
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作者 陈丽清 吴媛 +1 位作者 尹亚玲 刘金梅 《物理实验》 2024年第1期14-21,共8页
近20年,国际量子科技取得重大进展,在未来科技发展中占据重要地位.因此,在物理专业本科实验教学中设置量子物理实验,让学生深入理解微观量子物理基本原理,掌握一定的量子前沿技术非常必要.华东师范大学物理学专业自主开发量子物理本科... 近20年,国际量子科技取得重大进展,在未来科技发展中占据重要地位.因此,在物理专业本科实验教学中设置量子物理实验,让学生深入理解微观量子物理基本原理,掌握一定的量子前沿技术非常必要.华东师范大学物理学专业自主开发量子物理本科实验教学仪器和虚拟仿真实验,在物理学专业拔尖班开设量子物理实验,取得了优异的成果.本文详细介绍了华东师范大学量子物理实验课程设置以及实施过程,分析开展相关本科量子物理实验的可能性及其普及性,为全国高校开设量子物理实验课程提供参考. 展开更多
关键词 量子物理实验 真空场测量 海森堡不确定关系 引力波测量演示实验 量子光源
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“GNSS测量原理与应用”的STEM教学模式探索
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作者 贺小星 孙喜文 鲁铁定 《实验室研究与探索》 CAS 北大核心 2024年第2期135-139,共5页
在STEM教学模式下剖析了“GNSS测量原理与应用”课程的瓶颈,提出以STEM教育理念为向导的跨学科、跨专业融合测绘知识的课程体系教学新模式。面向“学、赛、研”三位一体教学框架,在协同创新中创建了立体化课程框架,搭建了互联网虚拟仿... 在STEM教学模式下剖析了“GNSS测量原理与应用”课程的瓶颈,提出以STEM教育理念为向导的跨学科、跨专业融合测绘知识的课程体系教学新模式。面向“学、赛、研”三位一体教学框架,在协同创新中创建了立体化课程框架,搭建了互联网虚拟仿真实验STEM教学信息化平台,并对该模式进行教学应用,取得较好的教改成效,为测绘类课程的教学模式探索提供实践参考资料。 展开更多
关键词 STEM教育理念 GNSS测量原理与应用 教学模式
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基于PSD传感器的炸点三维坐标测量方法研究
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作者 宁威 褚文博 +1 位作者 张斌 赵冬娥 《计算机测量与控制》 2024年第3期195-203,共9页
针对野外炸点空间三维坐标测量的问题,提出了基于二维PSD位置传感器的炸点位置测量方法,构建了基于二维PSD位置传感器的炸点三维坐标测量系统;基于双目视觉原理建立了炸点空间三维坐标测量数学模型;研究了被动探测系统在野外远距离下的... 针对野外炸点空间三维坐标测量的问题,提出了基于二维PSD位置传感器的炸点位置测量方法,构建了基于二维PSD位置传感器的炸点三维坐标测量系统;基于双目视觉原理建立了炸点空间三维坐标测量数学模型;研究了被动探测系统在野外远距离下的标定技术;通过系统误差分解传递,分析了各参数的误差;在Matlab中分别绘制了炸点位置坐标3个维度的误差分布图,并分析了测量系统误差随炸点实际位置变化的分布情况;根据误差分布图得到了在理论100 m测试距离下X坐标最大测量误差约为0.292~0.303 m,Y坐标最大测量误差约为0.251~0.371 m,Z坐标最大测量误差0.270~0.336 m;最后通过静爆实验对测量方法正确性、被动探测系统标定技术可行性和测量系统功能性进行了验证,结果表明测量系统响应速度快且功能正常,被动探测系统标定技术具备可行性且操作方便,可适用于野外炸点位置的快速测量。 展开更多
关键词 PSD位置传感器 炸点位置测量 双目视觉原理 被动探测标定 误差分析
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插入道岔施工对运营高速道岔锁定轨温变化影响试验
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作者 谢铠泽 代玮武 +2 位作者 李义强 杨观星 朱学伟 《北京交通大学学报》 CAS CSCD 北大核心 2024年第1期66-73,共8页
为研究插入道岔施工(Turnout Inserting Construction,TIC)对既有高速道岔锁定轨温(StressFree Rail Temperature of Existing high-speed Turnout,SFRTET)的影响,提出基于双向应变法的锁定轨温变化测试方案,推导不同因素影响下的锁定... 为研究插入道岔施工(Turnout Inserting Construction,TIC)对既有高速道岔锁定轨温(StressFree Rail Temperature of Existing high-speed Turnout,SFRTET)的影响,提出基于双向应变法的锁定轨温变化测试方案,推导不同因素影响下的锁定轨温变化测量原理,确定监测数据的处理方法,并开展道岔锁定轨温变化现场试验研究.研究结果表明:基于锁定轨温变化监测方法确定的传感器安装时轨温与实测数据差异仅1.4%,验证了测试方案的合理性和数据处理方法的正确性;高速道岔的锁定轨温会受插入道岔各工序施工的影响,其在轨道结构拆除、轨道结构施工、道岔形位精调和工电联调3个工序中表现出显著的动态变化特征,即锁定轨温经历多次循环变化才达到稳定状态;既有高速道岔锁定轨温受侧股钢轨重新焊接施工影响最为显著,尤其是靠近焊接位置的侧股钢轨,其锁定轨温变化达12.87℃,建议侧股钢轨重新焊接工序尽可能选择在轨温接近既有道岔原锁定轨温时开展. 展开更多
关键词 铁道工程 高速道岔 锁定轨温 运营铁路 测试原理
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羽毛球运动中膝踝关节损伤的因素探讨 被引量:1
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作者 马国炎 《当代体育科技》 2024年第11期15-17,共3页
该文运用文献资料法,探讨羽毛球运动员膝踝关节损伤的原因。研究表明,弓箭步、跳跃杀球等动作模式和运动强度会增加膝关节受伤的概率;而频繁的加速减速则容易使踝关节扭伤。此外,该研究还探讨了损伤的生物力学原理和个体差异,建议通过... 该文运用文献资料法,探讨羽毛球运动员膝踝关节损伤的原因。研究表明,弓箭步、跳跃杀球等动作模式和运动强度会增加膝关节受伤的概率;而频繁的加速减速则容易使踝关节扭伤。此外,该研究还探讨了损伤的生物力学原理和个体差异,建议通过增强肌肉稳定性、关节活动度,加强踝关节周围肌群训练,降低损伤发生率。该研究结果对制订运动员训练计划和预防伤害策略具有重要指导意义。 展开更多
关键词 羽毛球运动员 膝踝关节损伤 生物力学原理 预防措施
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中波广播发射机的工作原理与故障处理措施研究
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作者 何红霞 《电视技术》 2024年第7期40-43,共4页
以数字调幅(Digital Amplitude Modulation,DAM)全固态10 kW中波广播发射机为研究对象,介绍中波广播发射机的各个系统及工作原理,重点分析引起发射机故障的原因,并提出故障处理措施和注意事项,旨在为中波广播行业的设备故障处理提供参考。
关键词 中波 广播发射机 工作原理 故障原因 处理措施
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探讨提高地质矿产勘查及找矿技术的方法 被引量:1
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作者 侯剑辉 谭志勤 赖伟文 《世界有色金属》 2024年第2期115-117,共3页
地质矿产资源的开发与利用直接影响着我国经济建设,切实提高地质矿产勘查技术应用水平与效果,可以更好推动我国经济建设基础性工作发展,同时也能更好满足各行业开采生产所需基础原料。针对此,文章通过阐述地质矿产技术应用的必要性及其... 地质矿产资源的开发与利用直接影响着我国经济建设,切实提高地质矿产勘查技术应用水平与效果,可以更好推动我国经济建设基础性工作发展,同时也能更好满足各行业开采生产所需基础原料。针对此,文章通过阐述地质矿产技术应用的必要性及其原则,深入探讨了现阶段我国地质矿产勘查及找矿工作存在的问题,并提出地质矿产勘查及找矿技术提高的有效途径,致力于解决地质矿产勘查工作问题,不断增强找矿效率,从而提高矿产资源利用率,促使我国地质矿产勘查及找矿工作高质量、高效率开展。 展开更多
关键词 地质矿产资源 勘查工作 找矿技术 应用原则 问题 提升对策
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