流致振动电磁测量装置的研究

流致振动其本质是一个固液耦合问题，数学处理十分复杂，这里介绍一种电磁测量方法。由于测量中，探测器和流体管道不存在相对运动和影响流场的问题,提高了测量的精度和可信度。     

一种高精度、大量程时间间隔计数器的设计

时间间隔测量方法有多种,如计数法、游标法、模拟内插法、延迟线内插法、时间电压变换法等.通过对这几种测量方法的分析比较,提出了一种大量程、高精度的时间间隔测量方法,并从实现原理和设计方法进行了阐述.该方法已成功应用于GPS铷钟中,对于同类时间间隔计数器设计具有借鉴意义.     

测量二次电子空间分布特征矩阵法的有效性分析

为了准确测量不同材料在实际环境中的二次电子空间分布，设计了一种新型的二次电子发射空间分布测量结构，给出了实验测量原理，用求解特征矩阵的方法对实验结果进行处理，得到了所需的二次电子空间分布。通过模拟计算对该测量方法进行了校验，模拟结果与假设二次电子空间分布函数相吻合，表明该测量方法可靠、测量精度高，为后续样机研制奠定了理论基础。     

含钚物料中子多重性测量技术研究

中子多重性测量技术作为一种全新的NDA分析方法，主要用于核保障领域的核材料衡算测量，是传统符合中子测量方法的改进。使用该技术可实现复杂情况下样品的准确测量。     

温度噪声相关测速方法的系统误差与自标定

研究了流体噪声的湍流传递行为及信号源的性质对相关测速系统的影响，分析了相关测速系统的系统误差，并提出了理论修正该误差的方法，使得相关测速成为一种绝对的测量方法。在理论分析的基础上进行了实验研究，理论与实践得到了较好的统一。     

环境空气中氡的监测方法

本文介绍了我国常用的环境空气中氡的测量方法和仪器。文中还针对每一种测量方法的适用范围和注意事项等作了评价,最后简要叙述了氡浓度测量的质量保证措施。     

天然γ—γ能谱测量的理论及其初步应用

从理论上对建立在全谱测量基础上的天然γ－γ能谱测量技术进行了较为详尽的分析。模型实验及野外现场试验表明，这一测量技术不仅可以测定Ｕ、Ｔｈ、Ｋ的含量，还可给出有关岩性参数。该方法使用方便、工作安全，是一种切实可行的地面放射性测量方法。     

活性炭吸附法测量铀尾矿氡析出率

介绍一种用活性炭吸附法测量铀尾矿表面氡析出率的方法，简要叙述了采样器和测量仪器的性能、特点，刻度及测量方法。通过在铀尾矿库的现场连续一年的监测，研究铀尾矿库年氡析出率的变化规律，总结测量年平均氡析出率的最佳季节和条件。     

金属活动态测量方法在层间氧化带砂岩型铀矿勘查中的初步试验

介绍了金属活动态测量方法的研发、找矿机理、金属活动态测量中的循序提取与偏提取分析流程的差异，以及金属活动态测量方法在2个已知层间氧化带砂岩型铀矿上试验的情况；讨论了金属活动态测量方法找铀的适用性及存在的问题。对新方法的引进、试验需要求真务实，忌急于求成、急功近利。盲目套用金属活动态测量方法找铀矿，具有风险。     

用激光铀分析仪测定痕量铀

一、测量方法 采用国产WGJ-1型激光铀分析仪进行测量。测量方法有两种,即标准曲线法和标准加入法。标准曲线法是预先用不同浓度的标准液做出标准曲线,在测量样品后直接从曲线上查出相应的铀含量;这一方法在测量时对温度要求较高。标准加入法是在每次测量对加入一定量的标准溶液,并与不加标准铀液时的计数相比以求出铀含量。本文的测量采用标准     

Cross section adjustment method based on random sampling technique

A cross section adjustment method based on the random sampling technique is proposed. In the proposed method, correlations among cross sections and core parameters are used instead of sensitivity coefficients of cross sections, which are necessary in the conventional method. The correlations are statistically estimated by the random sampling technique. The proposed method is theoretically consistent with the conventional method and provides comparable adjusted cross sections when sufficient number of random sampling is taken into account. The proposed method would be suitable for practical light water reactor (LWR) core analysis since estimation of sensitivity coefficients, which requires considerable computational cost in typical LWR problems, is not necessary. Through a benchmark problem in simple pin-cell geometry, adjusted cross sections by the present and the conventional cross section adjustment method are compared. The adjusted cross sections by the present method well reproduce the conventional ones, thus the feasibility of the present method is confirmed.     

A unified approach for numerical calculation of space-dependent kinetic equation

A unified numerical method based on the factorization approach is developed to solve the space-dependent neutron kinetic equation. Various numerical methods for solving the space-dependent kinetic equation have been developed so far. These methods can be classified into two categories, i.e., the direct and the factorization methods. The factorization method is known as an effective numerical method. In the present study, a new factorization method named the multigrid amplitude function (MAF) method is developed. Unlike the improved quasi-static (IQS) method, an independent amplitude function is assigned for each spatial region and energy group in the MAF method. The MAF method is a generalization of conventional methods, e.g., the frequency transform, IQS, and Theta methods. To evaluate the amplitude function in the MAF method, the time-dependent coarse-mesh finite difference (TCMFD) method is developed. The MAF method is implemented into a space-dependent kinetic code on the basis of the analytical polynomial nodal method. In order to verify the effectiveness of the MAF method, the TWIGL, Langenbuch, Maurer, and Werner (LMW), and Laboratorium für Reaktorregelung and Anlagensicherung (LRA) benchmark problems are analyzed. The calculation results show the effectiveness of the present method.     

Extended cross-section adjustment method to improve the prediction accuracy of core parameters

An extended cross-section adjustment method has been developed to improve the prediction accuracy of target core parameters. The present method is on the basis of a cross-section adjustment method which minimizes the uncertainties of target core parameters under the conditions that integral experimental data are given. The present method enables us to enhance the prediction accuracy better than the conventional cross-section adjustment method by taking into account the target core parameters, as well as the extended bias factor method. In addition, it is proved that the present method is equivalent to the extended bias factor method when only one target core parameter is taken into account. The present method is implemented in an existing cross-section adjustment solver. Numerical calculations verify the derived formulation and demonstrate an applicability of an adjusted cross-section set which is specialized for the target core parameters.     

对流传热问题的粒子-网格混合方法数值模拟

移动粒子半隐式（MPS）方法是一种完全基于拉格朗日体系的粒子法，应用于不可压缩流体。MPS方法在描述存在大变形和相变的问题时具有很大的优势。然而当MPS方法中的Laplace模型应用于求解能量方程时会存在求解不精确的情况。本文在MPS方法的基础上，提出了一种粒子 网格混合求解方法。通过MPS方法求解动量守恒方程，耦合有限体积法（FVM）求解能量守恒方程，以达到对对流传热问题的精确求解。对一维导热问题进行了方法验证，证明了粒子 网格混合方法求解导热的有效性，并有较高的求解精度。利用粒子-网格混合方法模拟了方腔内的自然对流，结果表明，基于MPS方法和FVM的耦合方法可用于求解对流传热问题。     

Seismic soil-structure interaction by the superposition method

The superposition technique is a simple yet powerful method for soil-structure seismic interaction problems. The method essentially consists of obtaining total motions by superposing free field motions and interaction motions, both previously calculated in separate analyses. Although this method is strictly applicable only to linear systems, the equivalent linear method is easily incorporated in order to approximate soil non-linearities. The superposition technique is valid for 3-D geometries, and allows for a seismic environment consisting of any kind of body or surface waves, or combinations thereof. The method is explained in detail, and three case studies are also summarized as an illustration of the flexibility of the method.     

一种γ能谱光滑效果评价方法

在γ能谱数据处理中需要对测量能谱进行光滑以降低统计涨落。实际应用中,针对不同的γ能谱,需要对各种能谱光滑算法的光滑效果进行科学的比较和评价,选择最佳的能谱光滑算法及最佳光滑参数。文章从γ能谱计数的统计涨落规律出发,提出了一种评价能谱光滑算法效果的方法,给出了评价参数,并计算了光滑效果的等效测量时间。根据实验测量的γ能谱数据,采用5点三次多项式拟合最小二乘法对不同光滑次数的光滑效果进行了对比,优选了光滑算法的光滑次数参数,并给出了等效测量时间,提高了谱数据处理的精度和准确度。     

α放射性比的测定方法

采用了3种α放射性比的测定方法:几何级数法、外推法和曲线拟合法。检验了几何级数法的可靠性。把外推法、曲线拟合法的结果与几何级数法的结果作了比较。     

Two methods for seismic analysis of non-classically damped systems

Two methods of seismic analysis of non-classically damped systems are compared. The first method is an extension of the Foss method (called the modified Foss method here) in which the response in the time domain is represented in terms of real modal vectors and relative displacements and velocities of the equivalent single-degree-of-freedom (SDOF) systems. In the second method, known as the canonical method, a different set of real modal vectors along with sine and cosine responses of the equivalent SDOF systems are used. It is shown that the canonical method can be derived along the same lines as the modified Foss method. The time domain responses from the two methods are identical and the corresponding response spectra responses comparable. The modified Foss method is preferred because of the physical significance of the relative displacements and velocities used in the method.     

材料电磁脉冲屏蔽效能的时域测量方法

材料电磁屏蔽效能的窗口法测量本质上是一种孔缝耦合效应的测量,具有低频响应不好,测量误差大等不足.且窗口法难以实现材料对电磁脉冲的屏蔽效能的测量.针对窗口法的不足,提出了试件法测量材料电磁脉冲屏蔽效能的试验方法.给出了试件法的原理、试件外环境场的获取方法及试件内测点的布局等关键技术.与窗口法相比,试件法具有试验简单、不需要微波暗室、试验效率高,试验数据可靠等一系列优点.利用试件法对某特种水泥材料的电磁脉冲屏蔽效能进行了测量,测量结果与理论分析符合得较好,证明了该试验方法的有效性.     

A hybrid method to generate few-group cross sections for fast reactor analysis

The accuracy of fast reactor core calculation is usually determined by the accuracy of self-shielded few-group cross sections. To further improve the accuracy of cross section generation, a hybrid method is proposed. In the hybrid method, the Monte-Carlo method is used to deal with the resonance effect in both the resolved and unresolved resonance range. The self-shielded ultrafine-group total, fission and elastic scattering cross sections are tallied by the Monte-Carlo method. The scattering transfer matrices are then generated in a synthesis way by using the tallied elastic scattering cross sections and a problem-independent elastic scattering function. The angular flux moments for the group condensation are calculated in an explicit deterministic way. Several tests are done to verify the hybrid method. The results show that the hybrid method avoids the disadvantages of both the traditional deterministic method and the pure Monte-Carlo method. It is a more accurate method to generate the few-group cross sections for fast reactor cores.