Prospects for development of nanometrology

The ensemble of possible and existing nano-objects and nanomaterials is treated as a multilevel multidimensional system. We introduce the quantitative and qualitative characteristics of elements of the system and give a graphical representation for it. A systems approach makes it possible to establish a basis for a continuously updateable and refineable database including the important properties of nano-objects and their interconnections. Creation of such a database is expedient for dynamic data support of nanometrology in its fundamental and applied aspects.     

Quasi-quantitative measures of research performance: An assessment of construct validity and reliability

This paper argues that research performance is essentially a multidimensional concept which cannot be encapsulated into a single universal criterion. Various indicators used in quantitative studies on research performance at micro or meso-levels can be classified into two broad categories: (i) objective or quantitative indicators (e.g. counts of publications, patents, algorithms or other artifacts of research output) and (ii) subjective or qualitative indicators which represent evaluative judgement of peers, usually measured on Likert or semantic differential scales. Because of their weak measurement properties, subjective indicators can also be designated as quasi-quantitative measures. This paper is concerned with the factorial structure and construct validity of quasi-quantitative measures of research performance used in a large-scale empirical study carried out in India. In this study, a reflective measurement model incorporating four latent variables (R & D effectiveness, Recognition, User-oriented effectiveness and Administrative effectiveness) is assumed. The latent variables are operationalized through thirteen indicators measured on 5-point semantic differential scales. Convergent validity, discriminant validity and reliability of the measurement model are tested through LISREL procedure.     

Fragmentation of the Intellectual Structure of Political Communication Study: Some Empirical Evidence

This study applies a method of author co-citation analysis to examine the intellectual structure of political communication study. Fifty one influential authors were selected from active members of the Political Communication Divisions of the International Communication Association (ICA), the National Communication Association (NCA), and the American Political Science Association (APSA). The results of the multidimensional scaling analysis and cluster analysis of these 51 selected authors' co-citation patterns show that intellectual fragmentation exists in political communication research; scholars with different academic backgrounds exhibit specialties using particular research approaches to study certain subjects in the field; scholars do not have much information exchange, and thus they are intellectually separate and confined within the boundaries of each fragment. The findings of this quantitative study complements and cross-validates the assessment made by other traditional qualitative reviews about the field.     

Qualitative analysis of classes of motion for multiresonant systems I. An algebraic method

Summary. A general multiresonant system is considered, in which the linear frequency and, possibly, a forcing frequency are involved in a set of linear conditions. The nature of the resonances is first discussed, by distinguishing independent and dependent equations, and both the analysis and design problems of the system are addressed. Rules are then given to construct the qualitative form of the AMEs to any desired order. Two families of terms are identified: improper resonant terms (not associated with any resonance conditions) and proper resonant terms (depending on the specific conditions), sub-divided into primary (of lower order) and secondary (of higher order). Theorems are proved to show that both improper and secondary resonant terms have no qualitative but only quantitative effects on classes of motion; reference is therefore made to reduced equations. An algebraic algorithm is illustrated to determine classes of motion, using only the integer resonance coefficients. The concept of degree of constraint of a given resonance condition is introduced, entailing a hierarchic order among the resonance conditions, the implications of which are discussed. Finally, some numerical simulations are shown to test the robustness of classes of motion to higher-order terms not accounted for in the asymptotic analysis.     

Type of empirical research reports as an explanatory factor in citation performance of psychiatric research

In all fields of human sciences there has long been a debate whether research of these fields should closely follow the traditional method with accurate measurements and statistical inference. More qualitative approaches have been proposed, by which is ment that the research aim is to use the data in their qualitative form. The purpose of this study was to describe the differences in citations between qualitative and quantitative empirical reports. A total of 262 published reports of research pertaining to the therapeutic community and psychiatric wards in a variety of treatment settings from 1987 to 1992 were analyzed. The main finding of this study was that quantitative reports were more frequently cited than qualitative ones — also when some confounding factors were controlled.     

Small,balanced, efficient,optimal, and near rotatable response surface designs for factorial experiments asymmetrical in some quantitative,qualitative factors

We present a structured method of constructing cost-efficient response surface designs (RSDs) as compared to the replicated central composite designs (RCCDs), that are useful for modelling and optimization of the experiments asymmetric in some qualitative, quantitative factors with at least two unrestricted quantitative factors while the remaining take two or three levels. We demonstrate the method by designing various experimental situations in 3 to 6 factors, and the analysis competency of the RSDs by analysing a published data set from an optimization experiment. The structural and prediction properties make our RSDs a good alternative to the known RSDs.     

Do density oscillations exist near the free surface of 4He?

Variational calculations are carried out for liquid ⁴He with a free surface. Five classes of wave functions are studied, four of which permit the density profile to exhibit oscillations near the surface. We conclude that it is not possible to determine with certainty whether density oscillations exist by variational methods alone. On the other hand, certain qualitative features of the layered structure and quantitative bounds on the extent of the oscillations can be observed, if the latter indeed exist. These observations lead us to believe that effects of a layered structure on, e.g., evaporation, surface scattering, and properties of adsorbates are probably too weak to be detectable.Work supported in part by the National Science Foundation through Grant No. DMR74-09661.Work carried out in connection with honors research for the B.A. degree.     

L-Moments Based Calibrated Variance Estimators Using Double Stratified Sampling

Variance is one of the most vital measures of dispersion widely employed in practical aspects. A commonly used approach for variance estimation is the traditional method of moments that is strongly influenced by the presence of extreme values, and thus its results cannot be relied on. Finding momentum from Koyuncu’s recent work, the present paper focuses first on proposing two classes of variance estimators based on linear moments (L-moments), and then employing them with auxiliary data under double stratified sampling to introduce a new class of calibration variance estimators using important properties of L-moments (L-location, L-cv, L-variance). Three populations are taken into account to assess the efficiency of the new estimators. The first and second populations are concerned with artificial data, and the third populations is concerned with real data. The percentage relative efficiency of the proposed estimators over existing ones is evaluated. In the presence of extreme values, our findings depict the superiority and high efficiency of the proposed classes over traditional classes. Hence, when auxiliary data is available along with extreme values, the proposed classes of estimators may be implemented in an extensive variety of sampling surveys.     

多维系统优化中马氏田口强相关问题研究

对传统马氏田口方法进行了介绍,分析了多维系统马氏田口优化中强相关问题的影响,提出了解决强相关问题的新方法——马氏田口M-P广义逆矩阵法。相对于传统的马氏田口逆矩阵法,马氏田口M-P广义逆矩阵法具有存在性、唯一性和通用性的优点,能更有效地应用于多维系统的优化实践。通过对某医院血粘度诊断系统的优化与分析,进一步证实了马氏田口M-P广义逆矩阵法的有效性。     

中国造船工业供应商评价指标体系与管理体制构建

对于中国造船企业，构建完整的供应商管理体系是其从分散型采购体系向一体化采购体系整合的关键步骤之一。本文主要针对中国造船工业供应商管理的特点以及所存在的不足，将质量、交付能力、价格、服务能力和持续改进这5个定量评价指标与供货商关系指标和供货商管理能力指标这2个定性评价指标相结合，运用AHP法，构建了造船行业的供应商评价指标体系，并依据这一指标体系，构建了与造船行业集中化采购体系相适应的供应商管理体制。     

关于线性和非线性系统内在的本质联系——多自由度非线性系统的定量和定性分析

多自由度非线性振动问题是历史性国际难题,其求解方法有数值解和渐近解析解或两者结合.基于近代有限元和子结构模态综合法的动力学建模方法,获得非线性系统动力学微分方程,其自由度几乎没有限制,对左端首次近似齐次方程进行模态分析,选取对响应有贡献的部分本征对,同样对右端激励和非线性伪力作模态变换,得到减缩后非线性系统耦合动力学微分方程.用数值方法求出系统非线性响应进行定量分析,也可获得在指定参数的变动中可能发生的主谐、超谐、亚谐和组合共振,极限环和分岔、混沌等各种非线性振动现象,但其缺点是不能作一般性定性分析.渐近解析解可进行分岔混沌现象的定性分析,但迄今只限于单、两自由度系统.若系统进入共振状态,系统响应相应急剧增加到大振幅振动,振动从微幅线性振动过渡到大幅非线性振动,因之系统运动主要由所涉及的各阶单一主模态所控制.这可称为"单模态共振理论".当发生共振时,单模态理论可把多自由度系统变换为解耦的多个单自由度系统,因之可采用渐近解析法逐个进行分岔混沌等定性分析,这就克服了高自由度非线性系统定性分析的困难.为了剖析线性和非线性系统内在的本质联系,论证了首次近似表征线性系统特性的主模态是沟通线性振动和非线性振动之间的桥梁,揭示了高自由度线性振动和非线性振动都是以线性主模态呈现其运动规律.     

Effective algorithms for parametrizing linear control systems over Ore algebras

In this paper, we study linear control systems over Ore algebras. Within this mathematical framework, we can simultaneously deal with different classes of linear control systems such as time-varying systems of ordinary differential equations (ODEs), differential time-delay systems, underdetermined systems of partial differential equations (PDEs), multidimensional discrete systems, multidimensional convolutional codes, etc. We give effective algorithms which check whether or not a linear control system over some Ore algebra is controllable, parametrizable, flat or π-free. This paper is dedicated to the memory of our dear friend and colleague Manuel Bronstein. The third author has been financially supported by the Control Training Site grant HPMT-CT-2001-00278 and the Deutsche Forschungsgemeinschaft during his stays at INRIA Sophia Antipolis.     

国防颠覆性技术在航天领域的发展应用研究

本文从国防颠覆性技术入手,进行定性遴选,聚焦重大国防颠覆性技术并建立指标评价体系,对重大国防颠覆性技术进行定量分析。并以此为基础,重点关注能在航天领域中产生巨大影响的重大国防颠覆性技术。这些在航天领域的颠覆性技术有望极大地提升航天系统的效能、大幅降低研制成本,推动航天技术水平的跨越式提升。     

Anatomy of JETRO's overseas technology monitoring: Bibliometrical and content analysis

By means of bibliometrics and content analysis, both quantitative and qualitative, based upon JETRO Technology Bulletin data-base, the authors reveal some properties of overseas monitoring for industrial technology and technology policy by Japan External Trade Organization (JETRO), specifically, identify the shift of focus in regional and technical field dimensions, depict the different modes of representative technical areas, and trace the relation between technology monitoring and government policy action.     

Fault tree developed by an object-based method improves requirements specification for safety-related systems

Fault tree analysis is frequently used to improve system reliability and safety. To be suitable for analysis of software in computerised safety-related systems, it has to be modified accordingly. This paper presents a new application: the fault trees developed by an object-based method. The object-based method integrates structural and behavioural models of a system. The developed fault tree includes information on structure and the failure behaviours of classes of the system. Away from traditional use of the fault tree, which for traditional systems emphasises qualitative and quantitative results, the result of the new application emphasises the process of fault tree development and its qualitative results. Such fault tree application reduces the probability of failures in the requirements specification phase within the software life cycle, which increases the reliability of its product; however, it does not confirm this in a quantitative manner.     

残疾人作业调适决策模型及应用

将作业调适分为硬调适和软调适,以成本最小为决策目标,建立残疾人作业调适的定性定量决策模型。基于残疾人动作分析的方法,建立残疾人作业能力差损模型,并以此构建作业软硬调适的成本计算模型,对残疾人的作业调适进行多层次决策。通过实例,对作业能力差损模型进行验证。结果显示,模型的效度及一致性较理想。     

Determination of Elastic Properties of Resected Human Breast Tissue Samples Using Optical Coherence Tomographic Elastography

Abstract: The present study is concerned with the application of optical coherence tomographic (OCT) elastography technique for quantitative assessment of the elastic properties of resected human breast tissue samples subjected to axial compressive loading in vitro. Three classes of breast tissue samples, namely normal, benign (fibroadenoma) and malignant (invasive ductal carcinoma), were considered. A speckle tracking technique based on two‐dimensional cross correlation was employed to track the speckle motion between original (pre‐compressed) and the displaced (post‐compressed) OCT images of the tissue samples for the measurement of displacement and strain maps. The overall data reduction approach for quantitative assessment of elastic properties was validated against the results of gelatin phantoms containing activated charcoal particles as scattering centres. Results are presented in the form of OCT images and displacement and axial strain maps for normal, benign and malignant breast tissue samples. Based on the stress–strain relationship obtained for these three classes, the values of stiffness coefficients were reported in terms of modulus of elasticity. Results of the study reveal significant differences between the two‐dimensional displacement vector maps of normal and cancerous breast tissue samples. The stiffness of benign tissue samples is found to be about two times higher than that of normal tissue samples, whereas for malignant samples, it is about four times higher, thereby signifying appreciable differences in the stiffness of cancerous and normal tissue samples.     

An introduction to multidimensional measurement using Rasch models

The act of constructing a measure requires a number of important assumptions. Principle among these assumptions is that the construct is unidimensional. In practice there are many instances when the assumption of unidimensionality does not hold, and where the application of a multidimensional measurement model is both technically appropriate and substantively advantageous. In this paper we illustrate the usefulness of a multidimensional approach to measurement with the Multidimensional Random Coefficient Multinomial Logit (MRCML) model, an extension of the unidimensional Rasch model. An empirical example is taken from a collection of embedded assessments administered to 541 students enrolled in middle school science classes with a hands-on science curriculum. Student achievement on these assessments are multidimensional in nature, but can also be treated as consecutive unidimensional estimates, or as is most common, as a composite unidimensional estimate. Structural parameters are estimated for each model using ConQuest, and model fit is compared. Student achievement in science is also compared across models. The multidimensional approach has the best fit to the data, and provides more reliable estimates of student achievement than under the consecutive unidimensional approach. Finally, at an interpretational level, the multidimensional approach may well provide richer information to the classroom teacher about the nature of student achievement.     

Qualitative Methods Used in the Assessment of Engineering Education

This article clarifies key concepts that undergird qualitative research, which is being used increasingly as engineering educators improve classrooms, programs, and institutions. The paper compares quantitative and qualitative research, describes some qualitative data collection strategies used in engineering education, addresses methods for establishing trustworthiness, and discusses strategies for analyzing qualitative data. Also included are illustrative examples of recent engineering education research that features qualitative data analysis and mixed‐method (quantitative and qualitative) approaches.     

Correlation between quality and quantity in scientific production: A case study of Iranian organizations from 1997 to 2006

In order to prevent the formation of a gap between the quality and quantity in Iranian scientific publications, this study makes an effort to analyze Iranian scientific publications indexed on the ISI Web of Science database using quantitative and qualitative scientometrics criteria over a ten year period. As a first step, all Iranian institutes were divided into three categories; universities, research institutes and other organizations. Then they were compared according to quantitative and qualitative criteria. Second, the correlation between the quality and quantity of the publications was measured. The research findings indicated that, according to qualitative criteria (citation, citation impact and percentage of cited documents) there are no meaningful differences among the three groups, while regarding quantitative criterion(number of papers), universities rank higher than the other two groups. The results also indicated that there is a positive and meaningful correlation among qualitative and quantitative criteria in the scholarly scientific publications conducted by Iranian organizations. In other words, in Iranian organizations the quality of publications increases as their quantity increases. The comparison of magnitude of correlation between these two criteria in the three categories reveals the fact that the correlation between number of papers and citations criterion in research institutes is stronger than the other two groups.