Fundamental Indices Research Articles

Minkowski Tensor Shape Analysis of Cellular, Granular and Porous Structures

Predicting physical properties of materials with spatially complex structures is one of the most challenging problems in material science. One key to a better understanding of such materials is the geometric characterization of their spatial structure. Minkowski tensors are tensorial shape indices that allow quantitative characterization of the anisotropy of complex materials and are particularly well suited for developing structure-property relationships for tensor-valued or orientation-dependent physical properties. They are fundamental shape indices, in some sense being the simplest generalization of the concepts of volume, surface and integral curvatures to tensor-valued quantities. Minkowski tensors are based on a solid mathematical foundation provided by integral and stochastic geometry, and are endowed with strong robustness and completeness theorems. The versatile definition of Minkowski tensors applies widely to different types of morphologies, including ordered and disordered structures. Fast linear-time algorithms are available for their computation. This article provides a practical overview of the different uses of Minkowski tensors to extract quantitative physically-relevant spatial structure information from experimental and simulated data, both in 2D and 3D. Applications are presented that quantify (a) alignment of co-polymer films by an electric field imaged by surface force microscopy; (b) local cell anisotropy of spherical bead pack models for granular matter and of closed-cell liquid foam models; (c) surface orientation in open-cell solid foams studied by X-ray tomography; and (d) defect densities and locations in molecular dynamics simulations of crystalline copper.

Measurements and attenuation of erythemal radiation in Central Spain

AbstractBiologically active ultraviolet (UVER, 280–400 nm) and global (300–3000 nm) solar irradiances have been recorded and analysed in a rural area in Valladolid (Spain) for a period of 49 months between June 2002 and December 2008. UVER daily measurements follow the pattern of the solar elevation angle and maximum hourly average irradiances occur in July, 0.20 Wm−2 and minimum, 0.03 Wm−2, in December at noon; the total accumulated UVER along a year reaches 1470 kJm−2. The temporal evolution of the erythemal ultraviolet radiation and its distribution under different sky conditions have been studied, being 25% clear, 57% partly cloudy and 18% overcast days. The most representative statistical characteristics of the hourly and daily UVER data have been evaluated for different sky conditions and the fundamental indices show symmetry with respect to solar noon. Maximum values may be considered as representative of the UVER characteristics in the area, whereas the minimum values are not significant, mainly during summertime. The UVER records show quite stable values in the analysed period, particularly along the months of July. The isoline‐set of the first four moment distribution of the hourly UVER values has been plotted and the relative gradients are shown. The results are compared with the values obtained in other stations. The UVER cloud attenuation through the atmosphere shows that the transmitted percentage increases from winter to summer and a maximum value of 10% was achieved in July and a minimum of 30% in winter and spring. Copyright © 2011 Royal Meteorological Society

More Fundamental and Practical Indices Based on the Data Analysis of NIPPON DATA 80 Might Be Needed for Clinical Settings

More Fundamental and Practical Indices Based on the Data Analysis of NIPPON DATA 80 Might Be Needed for Clinical Settings

More Fundamental and Practical Indices Based on the Data Analysis of NIPPON DATA 80 Might Be Needed for Clinical Settings

More Fundamental and Practical Indices Based on the Data Analysis of NIPPON DATA 80 Might Be Needed for Clinical Settings

The influence of the legal and economical environment and the profile of activities on the optimal design features of a natural-gas-fired combined heat and power plant

Abstract The paper deals with the effect of some selected quantities occurring in the legal and economical environment on the optimal values of some selected design quantities of a natural-gas-fired CHP plant. This trend of investigations results from the newly observed legal changes in the legislation concerning new forms of mechanisms supporting the combined production of electricity and heat. Special stress was exerted on changes resulting from the formulation of two directives, viz. 2003/7/EC and 2004/8/EC. For the purpose of realising this task, a reference structure of a CHP plant was selected. For the steam-water part of the plant thirteen quantities were selected, determining the design features of the most essential components of this part of the system. These quantities served as decision variables in processes of optimisation. As the objective function the break-even price of electricity was assumed. The second part of the paper presents the results of sensitivity analyses of the fundamental indices of the energy and economical effectiveness to failures in the adherence of the optimal values of the respective design quantities, as well as the results of investigations on the effect of the operation time of the plant in the course of one year.

Fundamental Indexation: Rebalancing Assumptions and Performance

The authors show that the performance of a fundamental index with annual rebalancing, as proposed by Arnott, Hsu, and Moore [2005], can be highly sensitive to the subjective choice of when to rebalance. For the year 2009, for example, they found that a fundamental index rebalanced every March outperformed the capitalization-weighted index by over 10%, whereas a fundamental index rebalanced every September underperformed. The authors provide intuitive and statistical evidence in support of the hypothesis that if two fundamental indices diverge, they do not subsequently tend to mean revert (i.e., the gap is likely to be permanent). The performance ambiguity is an undesirable feature for an index that is used for benchmarking purposes. The authors introduce the idea of blending multiple underlying fundamental indices, each one rebalanced annually but at different dates, as an example of how to construct a more robust fundamental index without increasing turnover.

Exact Reliability Formula for Consecutive-$k$-Out-of-$n$ Repairable Systems

In this paper, consecutive-k -out-of-n repairable systems are studied. We assume that both the working time, and the repair time of each component are exponentially distributed, and every component after repair is as good as new. Each component is either a key component, or an ordinary component so we can adopt a priority repair rule for key components. First, the state transition probabilities as well as their Laplace transforms for the systems are derived. Second, several fundamental reliability indices (including availability, the mean time to the first failure, reliability, and the rate of occurrence of failure) of the systems are obtained explicitly. Finally, one example is shown to explain the model, and the methodology developed in this paper.

Fundamental indexation: An active value strategy in disguise

In this paper we critically examine the novel concept of fundamental indexation. We argue that fundamental indexation is by definition nothing more than an (elegant) value strategy, because the weights of stocks in a fundamental index and a market capitalization-weighted index only differ as a result of differences in valuation ratios. Moreover, fundamental indices more resemble active investment strategies than classic passive indices, because (i) they appear to be at odds with market equilibrium, (ii) they do not represent a buy-and-hold strategy and (iii) they require several subjective choices. Last but not least, because fundamental indices are primarily designed for simplicity and appeal, they are unlikely to be the most efficient way of benefiting from the value premium. Compared to more sophisticated, multi-factor quantitative strategies, fundamental indexation is likely to be an even more inferior proposition.

Fundamental Indexation: An Active Value Strategy in Disguise

In this paper we critically examine the novel concept of fundamental indexation. We argue that fundamental indexation is by definition nothing more than an (elegant) value strategy, because the weights of stocks in a fundamental index and a market capitalization-weighted index only differ as a result of differences in valuation ratios. Moreover, fundamental indices more resemble active investment strategies than classic passive indices, because (i) they appear to be at odds with market equilibrium, (ii) they do not represent a buy-and-hold strategy and (iii) they require several subjective choices. Last but not least, because fundamental indices are primarily designed for simplicity and appeal, they are unlikely to be the most efficient way of benefiting from the value premium. Compared to more sophisticated, multi-factor quantitative strategies, fundamental indexation is likely to be an even more inferior proposition.

FROM CABINET TO COUCH: FREUD'S CLINICAL USE OF SCULPTURE

abstract This article aims to address and remedy the fact that Freud's clinical use of sculpture has received little sustained attention. After a brief review of the collection, Melanie Klein's clinical use of dolls is discussed as an initial basis for comparison. It then makes a detailed examination of primary evidence found in the published writings and private correspondence of the writer and analysand H.D. (Hilda Doolittle). H.D.'s analysis indicates that Freud used sculpture as an analogue for the ‘foreign body’ of psychical trauma, treating it as a representation of a representation, or Vorstellungrepräsentanz. The sculptures also served Freud's archaeological metaphor for the ‘otherness’ of the unconscious in ways that architectural fragments did not. The author then considers H.D.'s hallucination of Athena Nike and Freud's use of his own damaged sculpture of Athena to raise therapeutic questions about her phallic relation to the signifier in the treatment of her writer's block. This case study is further compared to Klein and to Jung in order to differentiate the use of objects in the clinical setting and to mark some of the limits Freud encountered in H.D.'s second analytic session. The author concludes that purely textual examinations of Freud may have greatly underestimated his clinical use of sculpture in recuperating lost memories as fundamental indices of desire.

Fundamental reliability of 1.5‐nm-thick silicon oxide gate films grown at 150°C by modified reactive ion beam deposition

The reliability of 1.5‐nm-thick silicon oxide gate films grown at 150°C by modified reactive ion beam deposition (RIBD) with in situ pyrolytic-gas passivation (PGP) using N2O and NF3 was investigated. RIBD uses low-energy-controlled reactive, ionized species and potentializes low-temperature film growth. Although the oxide films were grown at a low temperature of 150°C, their fundamental indices of reliability, such as the time-dependent dielectric breakdown lifetime and interface state density, were almost equivalent to those of oxide films grown at 850°C using a furnace. This is probably due to localized interfacial N and F atoms. The number density of interfacial N atoms was about seven times larger than that for the furnace-grown oxide films, and this is a key factor for improving the reliability through the compensation of residual inconsistent-state bonding sites.

Fundamentals and Stock Returns on the Warsaw Stock Exchange: the Application of Panel Data Models

This study examines the relationship between the future stock returns and the fundamental indices for companies listed on the Warsaw Stock Exchange in Poland. The fundamental exogenous variables were constructed following the previous research of Lev and Thiagarajan [1993], Abarbanell and Bushee [1997], Piotroski [2000] and Mohanram [2004], while the endogenous variable is defined as a one-year-ahead stock return. Empirical analysis based on a panel data model for 187 companies in years 1999-2003 finds that the future stock returns are significantly related to three fundamental variables, i.e. gross margin, sales and administrative expenses and return on assets. Stock returns are also strongly associated with price-earnings ratio. Most of the relationships do no longer hold in case of short-term future stock returns.

Daily and annual variations of erythemal ultraviolet radiation in Southwestern Spain

Abstract. The potential danger of ultraviolet (UV) radiation and its increasing levels at the Earth's surface due to ozone depletion have demanded worldwide representative measurements of UV radiation. This study presents four and one-half years of original records of high temporal resolution ultraviolet erythemal radiation (UVER) measured in Badajoz, Spain. Its principal aim is to statistically characterize the UVER magnitude and temporal variations, but also to address the interesting special cases of cloud-free and cloudy skies. In particular, the study reports reliable values of fundamental statistical indices, which can serve as relevant values for comparison with other studies and model results. Moreover, the daily and annual evolution of the main central moments of the distribution function are analyzed and interpreted in terms of the forcing and attenuation sources. The analysis focuses on two different temporal scales: hourly and daily values. Integrated hourly and daily data allow for the study of daily and annual variations of the fundamental statistical indices. All of them exhibit high symmetry with respect to solar noon and to certain dates near summer and winter solstices. The analysis shows the great influence of cloudiness in the distribution of UVER values. Thus, both daily and hourly UVER data present a slightly asymmetrical, left tailed, mesokurtic distribution for all months, except for summer, when the lack of clouds produces a leptokurtic distribution which is skewed to the left.

Spatial Heterogeneity and Variability of a Large-Scale Vegetation Community Using a Power-Law Model

Spatial heterogeneity and stability are fundamental indices for describing vegetation communities. The spatial distribution characteristics of the vegetation in Nenjiang region of northeastern China were evaluated using a variance power-law model. The data fits the model well with estimates given for the levels of heterogeneity for not only single species but also the community as a whole. The linear regression indicates that the species in the community exhibit a consistently organized spatial pattern, as is often discovered in field surveys but rarely seen in artificial systems. The species deviations from the regression line, which exhibit a leptokurtic distribution, may reflect the variability of the community. Thus, the model provides a general tool for management and regulation of ecosystems, especially where there is human disturbances.

Risk–benefit analyses of SG tube maintenance based on probabilistic fracture mechanics

As an application of probabilistic fracture mechanics (PFM), a risk–benefit analysis was performed for the purpose of optimizing maintenance activities of steam generator (SG) tubes used in pressurized water reactors (PWRs). The probabilities of the SG tube leakage and rupture are defined as risks in this study. A model was made modifying pc-PRAISE (Piping Reliability Analysis Including Seismic Events) to evaluate the risks during 60 year operations due to stress corrosion cracking (SCC) of the tubes under various maintenance strategies for SG tubes. In the risk analysis, parameters such as inspection accuracy, inspection interval, sampling inspection and crack propagation law were selected for sensitivity analysis. Based on the risk analysis, a risk–benefit analysis was conducted when implementing two maintenance strategies taking both costs and revenues for 60 year operations into account. In the risk–benefit analysis, the expected cost of leakage or rupture was calculated by multiplying ‘probability of leakage or rupture’ by ‘expected loss of leakage or rupture accident’. To justify whether it is worthwhile implementing the maintenance strategies or not, the net present value (NPV) was calculated as an index, which is one of the most fundamental financial indices for decision-making based on the discounted cash flow (DCF) method. The results demonstrated that in the risk analysis, the risks are influenced significantly by the crack propagation law, accuracy of inspection and sampling inspection. In the risk–benefit analysis, it was suggested that investment to improve inspection accuracy would reduce the total costs of 60 year operations significantly and increase the NPV. Although the analysis was mainly conducted for SG tubes made of Inconel 600 mill anneal (MA) material, the analysis was also carried out for Inconel 690 thermal treatment (TT) material, making assumptions on its crack initiation and crack propagation law. In addition, the effect of introducing maintenance criteria, namely, operation with a crack justified by certain criteria, on NPV was evaluated.

Methods and materials for the measurement of subjective and objective measurements of image quality.

The evaluation of medical imaging systems may be performed using both subjective (e.g. high contrast limiting resolution, and low contrast detail detectability), and objective/physical (e.g. characteristic curve, signal-to-noise ratio, modulation transfer function, and Wiener spectra) indices of image quality. For the purposes of Quality Assurance subjective measurements currently have a wider usage in the clinical environment due to the inherent simplicity of the measurements; however, more rigorous objective approaches are gaining acceptability, and represent a paradigm for possible future QA measurements. Both approaches have their advantages and disadvantages. There is currently wide debate as to the interpretation of these measurements. However, there appears to be a lack of standardisation among scientists in the various approaches to making these measurements, and especially so in the case of objective indices; furthermore, the measurement protocol used must have a bearing on the interpretation of subsequent results. The purpose of this paper is to (i) present the most fundamental indices in the characterisation of 'image quality', and (ii) recommend approaches to the measurement of these indices.

E64d, a membrane-permeable cysteine protease inhibitor, attenuates the effects of parathyroid hormone on osteoblasts in vitro

Parathyroid hormone (PTH) activates calpains I and II (calcium-activated papain-like proteases) and stimulates the synthesis and secretion of cathepsin B (a lysosomal cysteine protease) in osteoblastic cells. Anabolic doses of PTH also stimulate osteoprogenitor cell proliferation and differentiation into mature, fully functional osteoblasts capable of elaborating bone matrix, whereas catabolic doses of PTH stimulate calcium mobilization and matrix turnover. Previous investigations in other cell types have demonstrated that calcium-activated calpains play a major role in regulating proliferation and differentiation by catalyzing limited regulatory proteolysis of nuclear proteins, transcription factors, and enzymes. We tested the hypothesis that inhibition of intracellular cysteine proteases such as the calpains will ablate PTH-mediated osteoblast proliferation and differentiation, two fundamental indices of bone anabolism. A brief preincubation with the membrane-permeable, irreversible cysteine protease inhibitor E64d (10 μg/mL) before short-term PTH treatment blunted PTH-induced cell proliferation in subconfluent cultures and also attenuated proliferation and inhibited differentiation in longer-term confluent cultures. This confirms the hypothesis that cysteine proteases such as the calpains are important in mediating the proliferative and prodifferentiating or anabolic effects of PTH on MC3T3-E1 cells in culture. Immunofluorescent localization demonstrated that calpain I, calpain II, and calpastatin (the endogenous calpain inhibitor) are abundant and widely distributed within actively proliferating MC3T3-E1 preosteoblasts. Since the calpains are active and stable at neutral intracellular pH levels in osteoblasts, whereas cathepsins are not, our results support a role for these calcium-activated regulatory proteases in mediating the anabolic effects of PTH in bone.

Towards predicting recruitment success of anchovyEngrauus capensisGilchrist in the southern Benguela system using environmental variables: a rule-based model

The construction of a rule-based model aimed at assisting in the management of the Cape anchovy Engraulis capensis by predicting the success of recruitment is described. Of the many environmental variables which, potentially, may give an indication of future recruitment, the fundamental physical indices of sea surface temperature and wind were selected for inclusion in the model. From simple regression and correlation analysis, qualitative rules were constructed relating recruitment success to wind frequency, wind velocity and sea surface temperature in one or more of the spawning, transport and recruitment (nursery) areas of the anchovy. By calibration of the rules, and the consideration of annual spawner biomass, it was possible to obtain a good estimate of observed recruitment. The model was then used to examine the implications of a number of possible environmental scenarios on annual recruitment. Results from the statistical analyses and those from the model indicate that transport of larvae may be o...

GM-CSF is an autocrine mitogenic factor for normal human osteoblastic cells isolated from the trabecular bone surface

Parathyroid hormone (PTH) activates calpains I and II (calcium-activated papain-like proteases) and stimulates the synthesis and secretion of cathepsin B (a lysosomal cysteine protease) in osteoblastic cells. Anabolic doses of PTH also stimulate osteoprogenitor cell proliferation and differentiation into mature, fully functional osteoblasts capable of elaborating bone matrix, whereas catabolic doses of PTH stimulate calcium mobilization and matrix turnover. Previous investigations in other cell types have demonstrated that calcium-activated calpains play a major role in regulating proliferation and differentiation by catalyzing limited regulatory proteolysis of nuclear proteins, transcription factors, and enzymes. We tested the hypothesis that inhibition of intracellular cysteine proteases such as the calpains will ablate PTH-mediated osteoblast proliferation and differentiation, two fundamental indices of bone anabolism. A brief preincubation with the membrane-permeable, irreversible cysteine protease inhibitor E64d (10 μg/mL) before short-term PTH treatment blunted PTH-induced cell proliferation in subconfluent cultures and also attenuated proliferation and inhibited differentiation in longer-term confluent cultures. This confirms the hypothesis that cysteine proteases such as the calpains are important in mediating the proliferative and prodifferentiating or anabolic effects of PTH on MC3T3-E1 cells in culture. Immunofluorescent localization demonstrated that calpain I, calpain II, and calpastatin (the endogenous calpain inhibitor) are abundant and widely distributed within actively proliferating MC3T3-E1 preosteoblasts. Since the calpains are active and stable at neutral intracellular pH levels in osteoblasts, whereas cathepsins are not, our results support a role for these calcium-activated regulatory proteases in mediating the anabolic effects of PTH in bone.

Emotional effect and reminding in literary processing

This paper presents a series of empirical studies to show some psychological characteristics of self-relevant information processing in literary vs. non- (or less) literary reading. Three experiments were conducted to study the emotional effect, and the verbalized remindings, of short literary, expository and/or descriptive texts on clearly similar topics and of similar length. The subjects were 288 students of an academically eminent secondary school in Budapest, males and females approximately in equal numbers, all aged 17. In each experiment different groups read only one of the texts which were all segmented into three parts. In experiment 1, following each segment, the subjects' task was to fill in a form which measured the most fundamental indices of emotional effect and, on completion of the reading, to give the formal-thematic effect on the basis of a rating. In experiment 2 the task was to write down all the earlier — direct or indirect — experiences the subjects were reminded of by any part of the given segment. The frequencies of different — more or less personal — content categories of remindings and other responses were measured. In experiment 3, two keywords, with which propositions were directly connected, or related, were given from each segment of the texts. The task was to put down all the earlier experiences the subjects were reminded of by them. As part of that experiment the members of the control group were given the same keywords. Beside the frequencies of the content categories, some formal characteristics of the responses were also measured. It was shown that though idiosyncrasies have a serious role in the self-relevant processing, a significant part of the variance of the effect can be ascribed to text characteristics. It is also apparent that while processing a literary text as a specific discourse, the reader relies not only upon his/her remindings coming from personally experienced, everyday life events directly, but to a great extent also upon the discourse interwoven with his/her earlier film, literary, music, fine arts experiences. A literary text exerts a strong influence on the reader's self because it often has multiple context cues and meanings. Remindings help with text-understanding insofar as the enrichment of the reader's identity takes places as an outcome of the cues in the text. General consequences from the point of view of the reader's self-system and of literary understanding as evaluative processing are discussed in connection with deviations in literary texts.