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1.
A polemic arose recently about the applicability of the t-expansion method to the calculation of the ground state energy E0 of the Rabi model. For specific choices of the trial function and very large number of involved connected moments, the t-expansion results are rather poor and exhibit considerable oscillations. In this Letter, we formulate the t-expansion method for trial functions containing two free parameters which capture two exactly solvable limits of the Rabi Hamiltonian. At each order of the t-series, E0 is assumed to be stationary with respect to the free parameters. A high accuracy of E0 estimates is achieved for small numbers (5 or 6) of involved connected moments, the relative error being smaller than 10−4 (0.01%) within the whole parameter space of the Rabi Hamiltonian. A special symmetrization of the trial function enables us to calculate also the first excited energy E1, with the relative error smaller than 10−2 (1%).  相似文献   
2.
Capillary zone electrophoresis ultraviolet (CZE-UV) has become increasingly popular for the charge heterogeneity determination of mAbs and vaccines. The ε-aminocaproic acid (eACA) CZE-UV method has been used as a rapid platform method. However, in the last years, several issues have been observed, for example, loss in electrophoretic resolution or baseline drifts. Evaluating the role of eACA on the reported issues, various laboratories were requested to provide their routinely used eACA CZE-UV methods, and background electrolyte compositions. Although every laboratory claimed to use the He et al. eACA CZE-UV method, most methods actually deviate from He's. Subsequently, a detailed interlaboratory study was designed wherein two commercially available mAbs (Waters’ Mass Check Standard mAb [pI 7] and NISTmAb [pI 9]) were provided to each laboratory, along with two detailed eACA CZE-UV protocols for a short-end, high-speed, and a long-end, high-resolution method. Ten laboratories participated each using their own instruments, and commodities, showing excellence method performance (relative standard deviations [RSDs] of percent time-corrected main peak areas from 0.2% to 1.9%, and RSDs of migration times from 0.7% to 1.8% [n = 50 per laboratory], analysis times in some cases as short as 2.5 min). This study clarified that eACA is not the main reason for the abovementioned variations.  相似文献   
3.
驱动轮最佳滑转率是汽车驱动防滑控制的关键参数,本文提出了一种基于车轮扭矩传感器的汽车加速工况驱动轮最佳滑转率的测定方法,阐述了该方法的测试原理和实验过程.通过实车实验,分别测定了汽车在不同载荷和节气门开度下驱动轮在冰、雪路面上的附着系数与滑转率的关系,得到了冰、雪路面上驱动轮最佳滑转率的控制范围,为研究汽车驱动防滑控制系统确定了最佳滑转率控制目标.  相似文献   
4.
The present paper describes an example of practical analysis of data from an application of visual analogue scales. Potentially useful and simple methods for analysing visual analogue scales are described for effective handling of complex data when the desire is to compare two or more groups of patients. Visual analogue scales were used to assess subjective tolerability in the International Prospective Primary Prevention Study in Hypertension, a large scale clinical trial. The methods are illustrated on the IPPPSH data.  相似文献   
5.
A common business strategy to promote product adoption in software industry is to provide a free trial version with limited functionalities of the commercial product to increase the installed user base. The increase of user base will lead to higher value of the software because of positive network effects. However, offering a free trial version may cannibalize some demand of the commercial software. This paper examines the tradeoff between network effects and the cannibalization effect, and aims to uncover the conditions under which firms should introduce the free trial product. We find that when network intensity is strong, it is more profitable for a software monopoly to offer free trial than to segment the market with two versions of different qualities. In addition, this paper solves the joint decision problem of finding the optimal quality for the firm’s free trial software and the optimal price of its commercial product.  相似文献   
6.
基于语言评价信息的知识资本要素识别方法   总被引:2,自引:0,他引:2  
知识资本是组织创造价值和获取竞争优势的关键资源, 其要素通常具有复杂的关联性, 如何识别知识资本的核心要素、原因要素和结果要素,对于组织进行知识资本管理具有重要意义.本文在构建了知识资本要素识别体系的基础上,借鉴决策试验和评价实验室报告的思想提出了一种基于语言评价信息的知识资本要素识别方法,通过处理和集结专家针对知识资本要素关联给出的语言评价信息,对知识资本要素进行排序与归类.最后通过一个实例分析说明了该方法的应用, 并说明了如何根据识别结果制定相应的策略以便进行知识资本的投资和控制.  相似文献   
7.
社区矫正制度在我国还是个新生事物,司法实践中观念陈旧、立法滞后等各方面的原因严重制约了我国社区矫正工作的开展。推动社区矫正制度在我国的深入开展,亟需构建完善的社区矫正法律体系,建立司法行政机关与相关部门的工作协调机制,加强司法所及社区矫正工作人员队伍的建设。  相似文献   
8.
为了在施工实践中更好地掌握和应用强夯原理、设计参数以及施工工法,在现场代表性区域内,通过不同参数下试夯试验的对比性研究,分析试验监测与检测相关数据,确定了工程可行性设计施工参数,包括夯击数、落距、夯距等。工程实践证明强夯法是一种经济、简便、可靠的大面积回填区域加固方法,对相关工程具有一定的实践与指导意义。  相似文献   
9.
    
Matrix metalloproteinase-9 (MMP-9) has been shown to play a key role in endothelial function and perhaps pivotal in the correlation between periodontal disease and cardiovascular disease (CVD). For the study, the impact of MMP-9 of periodontitis and CVD on serum and saliva concentrations was analyzed. For the study patients with periodontitis (n = 31), CVD (n = 31), periodontitis + CVD (n = 31), and healthy patients (n = 31) were enrolled. Clinical and demographic characteristics as well as serum and salivary MMP-9 were evaluated. MMP-9 concentrations in serum and saliva were statistically elevated in patients with CVD (p < 0.01) and in patients with periodontitis plus CVD (p < 0.001) compared to patients with periodontitis and healthy subjects. Multivariate regression analysis showed that c-reactive protein (hs-CRP) was the only significant predictor for MMP-9 serum (p < 0.001), whereas hs-CRP (p < 0.001) and total cholesterol (p = 0.029) were the statistically significant salivary MMP-9 predictors. This study evidenced that patients with CVD and periodontitis + CVD presented elevated MMP-9 concentrations in serum and saliva compared to patients with periodontitis and healthy subjects. Furthermore, hs-CRP was a negative predictor of serum and salivary MMP-9.  相似文献   
10.
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