A Network of Networks Perspective on Global Trade

PubMed Central

Maluck, Julian; Donner, Reik V.

2015-01-01

Mutually intertwined supply chains in contemporary economy result in a complex network of trade relationships with a highly non-trivial topology that varies with time. In order to understand the complex interrelationships among different countries and economic sectors, as well as their dynamics, a holistic view on the underlying structural properties of this network is necessary. This study employs multi-regional input-output data to decompose 186 national economies into 26 industry sectors and utilizes the approach of interdependent networks to analyze the substructure of the resulting international trade network for the years 1990–2011. The partition of the network into national economies is observed to be compatible with the notion of communities in the sense of complex network theory. By studying internal versus cross-subgraph contributions to established complex network metrics, new insights into the architecture of global trade are obtained, which allow to identify key elements of global economy. Specifically, financial services and business activities dominate domestic trade whereas electrical and machinery industries dominate foreign trade. In order to further specify each national sector’s role individually, (cross-)clustering coefficients and cross-betweenness are obtained for different pairs of subgraphs. The corresponding analysis reveals that specific industrial sectors tend to favor distinct directionality patterns and that the cross-clustering coefficient for geographically close country pairs is remarkably high, indicating that spatial factors are still of paramount importance for the organization of trade patterns in modern economy. Regarding the evolution of the trade network’s substructure, globalization is well-expressed by trends of several structural characteristics (e.g., link density and node strength) in the interacting network framework. Extreme events, such as the financial crisis 2008/2009, are manifested as anomalies superimposed to these trends. The marked reorganization of trade patterns, associated with this economic crisis in comparison to “normal” annual fluctuations in the network structure is traced and quantified by a new widely applicable generalization of the Hamming distance to weighted networks. PMID:26197439

Study on Spatial Spillover Effects of Logistics Industry Development for Economic Growth in the Yangtze River Delta City Cluster Based on Spatial Durbin Model.

PubMed

Xu, Xinxing; Wang, Yuhong

2017-12-04

The overall entropy method is used to evaluate the development level of the logistics industry in the city based on a mechanism analysis of the spillover effect of the development of the logistics industry on economic growth, according to the panel data of 26 cities in the Yangtze River delta. On this basis, the paper uses the spatial durbin model to study the direct impact of the development of the logistics industry on economic growth and the spatial spillover effect. The results show that the direct impact coefficient of the development of the logistics industry in the Yangtze River Delta urban agglomeration on local economic growth is 0.092, and the significant spatial spillover effect on the economic growth in the surrounding area is 0.197. Compared with the labor force input, capital investment and the degree of opening to the world, and government functions, the logistics industry's direct impact coefficient is the largest, other than capital investment; the coefficient of the spillover effect is higher than other control variables, making it a "strong engine" of the Yangtze River Delta urban agglomeration economic growth.

[Tobacco quality analysis of industrial classification of different years using near-infrared (NIR) spectrum].

PubMed

Wang, Yi; Xiang, Ma; Wen, Ya-Dong; Yu, Chun-Xia; Wang, Luo-Ping; Zhao, Long-Lian; Li, Jun-Hui

2012-11-01

In this study, tobacco quality analysis of main Industrial classification of different years was carried out applying spectrum projection and correlation methods. The group of data was near-infrared (NIR) spectrum from Hongta Tobacco (Group) Co., Ltd. 5730 tobacco leaf Industrial classification samples from Yuxi in Yunnan province from 2007 to 2010 year were collected using near infrared spectroscopy, which from different parts and colors and all belong to tobacco varieties of HONGDA. The conclusion showed that, when the samples were divided to two part by the ratio of 2:1 randomly as analysis and verification sets in the same year, the verification set corresponded with the analysis set applying spectrum projection because their correlation coefficients were above 0.98. The correlation coefficients between two different years applying spectrum projection were above 0.97. The highest correlation coefficient was the one between 2008 and 2009 year and the lowest correlation coefficient was the one between 2007 and 2010 year. At the same time, The study discussed a method to get the quantitative similarity values of different industrial classification samples. The similarity and consistency values were instructive in combination and replacement of tobacco leaf blending.

Application of process tomography in gas-solid fluidised beds in different scales and structures

NASA Astrophysics Data System (ADS)

Wang, H. G.; Che, H. Q.; Ye, J. M.; Tu, Q. Y.; Wu, Z. P.; Yang, W. Q.; Ocone, R.

2018-04-01

Gas-solid fluidised beds are commonly used in particle-related processes, e.g. for coal combustion and gasification in the power industry, and the coating and granulation process in the pharmaceutical industry. Because the operation efficiency depends on the gas-solid flow characteristics, it is necessary to investigate the flow behaviour. This paper is about the application of process tomography, including electrical capacitance tomography (ECT) and microwave tomography (MWT), in multi-scale gas-solid fluidisation processes in the pharmaceutical and power industries. This is the first time that both ECT and MWT have been applied for this purpose in multi-scale and complex structure. To evaluate the sensor design and image reconstruction and to investigate the effects of sensor structure and dimension on the image quality, a normalised sensitivity coefficient is introduced. In the meantime, computational fluid dynamic (CFD) analysis based on a computational particle fluid dynamic (CPFD) model and a two-phase fluid model (TFM) is used. Part of the CPFD-TFM simulation results are compared and validated by experimental results from ECT and/or MWT. By both simulation and experiment, the complex flow hydrodynamic behaviour in different scales is analysed. Time-series capacitance data are analysed both in time and frequency domains to reveal the flow characteristics.

Study of parameter identification using hybrid neural-genetic algorithm in electro-hydraulic servo system

NASA Astrophysics Data System (ADS)

Moon, Byung-Young

2005-12-01

The hybrid neural-genetic multi-model parameter estimation algorithm was demonstrated. This method can be applied to structured system identification of electro-hydraulic servo system. This algorithms consist of a recurrent incremental credit assignment(ICRA) neural network and a genetic algorithm. The ICRA neural network evaluates each member of a generation of model and genetic algorithm produces new generation of model. To evaluate the proposed method, electro-hydraulic servo system was designed and manufactured. The experiment was carried out to figure out the hybrid neural-genetic multi-model parameter estimation algorithm. As a result, the dynamic characteristics were obtained such as the parameters(mass, damping coefficient, bulk modulus, spring coefficient), which minimize total square error. The result of this study can be applied to hydraulic systems in industrial fields.

Defining the Ecological Coefficient of Performance for an Aircraft Propulsion System

NASA Astrophysics Data System (ADS)

Şöhret, Yasin

2018-05-01

The aircraft industry, along with other industries, is considered responsible these days regarding environmental issues. Therefore, the performance evaluation of aircraft propulsion systems should be conducted with respect to environmental and ecological considerations. The current paper aims to present the ecological coefficient of performance calculation methodology for aircraft propulsion systems. The ecological coefficient performance is a widely-preferred performance indicator of numerous energy conversion systems. On the basis of thermodynamic laws, the methodology used to determine the ecological coefficient of performance for an aircraft propulsion system is parametrically explained and illustrated in this paper for the first time. For a better understanding, to begin with, the exergy analysis of a turbojet engine is described in detail. Following this, the outputs of the analysis are employed to define the ecological coefficient of performance for a turbojet engine. At the end of the study, the ecological coefficient of performance is evaluated parametrically and discussed depending on selected engine design parameters and performance measures. The author asserts the ecological coefficient of performance to be a beneficial indicator for researchers interested in aircraft propulsion system design and related topics.

Study on Spatial Spillover Effects of Logistics Industry Development for Economic Growth in the Yangtze River Delta City Cluster Based on Spatial Durbin Model

PubMed Central

Xu, Xinxing

2017-01-01

The overall entropy method is used to evaluate the development level of the logistics industry in the city based on a mechanism analysis of the spillover effect of the development of the logistics industry on economic growth, according to the panel data of 26 cities in the Yangtze River delta. On this basis, the paper uses the spatial durbin model to study the direct impact of the development of the logistics industry on economic growth and the spatial spillover effect. The results show that the direct impact coefficient of the development of the logistics industry in the Yangtze River Delta urban agglomeration on local economic growth is 0.092, and the significant spatial spillover effect on the economic growth in the surrounding area is 0.197. Compared with the labor force input, capital investment and the degree of opening to the world, and government functions, the logistics industry’s direct impact coefficient is the largest, other than capital investment; the coefficient of the spillover effect is higher than other control variables, making it a “strong engine” of the Yangtze River Delta urban agglomeration economic growth. PMID:29207555

Investigating bias in squared regression structure coefficients

PubMed Central

Nimon, Kim F.; Zientek, Linda R.; Thompson, Bruce

2015-01-01

The importance of structure coefficients and analogs of regression weights for analysis within the general linear model (GLM) has been well-documented. The purpose of this study was to investigate bias in squared structure coefficients in the context of multiple regression and to determine if a formula that had been shown to correct for bias in squared Pearson correlation coefficients and coefficients of determination could be used to correct for bias in squared regression structure coefficients. Using data from a Monte Carlo simulation, this study found that squared regression structure coefficients corrected with Pratt's formula produced less biased estimates and might be more accurate and stable estimates of population squared regression structure coefficients than estimates with no such corrections. While our findings are in line with prior literature that identified multicollinearity as a predictor of bias in squared regression structure coefficients but not coefficients of determination, the findings from this study are unique in that the level of predictive power, number of predictors, and sample size were also observed to contribute bias in squared regression structure coefficients. PMID:26217273

Hierarchical structure graphitic-like/MoS2 film as superlubricity material

NASA Astrophysics Data System (ADS)

Gong, Zhenbin; Jia, Xiaolong; Ma, Wei; Zhang, Bin; Zhang, Junyan

2017-08-01

Friction and wear result in a great amount of energy loss and the invalidation of mechanical parts, thus it is necessary to minimize friction in practical application. In this study, the graphitic-like/MoS2 films with hierarchical structure were synthesized by the combination of pulse current plasma chemical-vapor deposition and medium frequency unbalanced magnetron sputtering in preheated environment. This hierarchical structure composite with multilayer nano sheets endows the films excellent tribological performance, which easily achieves macro superlubricity (friction coefficient ∼0.004) under humid air. Furthermore, it is expected that hierarchical structure of graphitic-like/MoS2 films could match the requirements of large scale, high bear-capacity and wear-resistance of actual working conditions, which could be widely used in the industrial production as a promising superlubricity material.

Microwave sensing for meat and fish structure evaluation

NASA Astrophysics Data System (ADS)

Clerjon, S.; Damez, J. L.

2007-04-01

Monitoring changes in muscle structure during the ageing of bovine meat and quality loss due to fish freezing are major industrial challenges. During ageing, bovine muscle becomes tender through muscle fibre deterioration, and full control of this process is essential. Conversely, degradation of fish muscle, often due to long storage or a freezing cycle, lowers quality. To improve competitiveness, and to respond to consumer quality demand, muscle structure needs to be evaluated in-line. We present here a polarimetric microwave method (10-24 GHz) consisting in free space and contact reflection coefficient measurements using a horn antenna and rectangular probes, respectively. This method is based on the measurement of dielectric properties of tissues parallel and perpendicular to muscle fibre directions. The dielectric properties of structured tissues such as muscles are anisotropic, but during processing structural disorganization reduces this anisotropy. The method is illustrated by the discrimination of fresh and frozen-thawed fish fillets and by monitoring of meat ageing.

Review on Material Synthesis and Characterization of Sodium (Na) Super-Ionic Conductor (NASICON)

NASA Astrophysics Data System (ADS)

Kimpa, M. I.; Mayzan, M. Z. H.; Yabagi, J. A.; Nmaya, M. M.; Isah, K. U.; Agam, M. A.

2018-04-01

Sodium (Na) Super Ionic Conductor (NASICON) has general formula Na1+ x Zr2P3- xSi x O12 (0 ≤x ≤ 3) derived from its parent compound, sodium zirconium phosphate NaZr2(PO4)3 (NZP) which belong to a rhombohedral crystal structure. This material consists of three-dimensional structure with interesting features such as low thermal expansion coefficient, thermal stability, gas sensor and nuclear waste immobilization that make it viable for industrial applications. Current study presents comprehensive studies on the synthesis and essential characteristics required to understand the theory behind the mechanism that justifies the study of NASICON structure and its application such as lithium ion rechargeable battery, gas sensor, and nuclear waste immobilization and so on.

Industrial pollution and the management of river water quality: a model of Kelani River, Sri Lanka.

PubMed

Gunawardena, Asha; Wijeratne, E M S; White, Ben; Hailu, Atakelty; Pandit, Ram

2017-08-19

Water quality of the Kelani River has become a critical issue in Sri Lanka due to the high cost of maintaining drinking water standards and the market and non-market costs of deteriorating river ecosystem services. By integrating a catchment model with a river model of water quality, we developed a method to estimate the effect of pollution sources on ambient water quality. Using integrated model simulations, we estimate (1) the relative contribution from point (industrial and domestic) and non-point sources (river catchment) to river water quality and (2) pollutant transfer coefficients for zones along the lower section of the river. Transfer coefficients provide the basis for policy analyses in relation to the location of new industries and the setting of priorities for industrial pollution control. They also offer valuable information to design socially optimal economic policy to manage industrialized river catchments.

Assembling of carbon nanotubes film responding to significant reduction wear and friction on steel surface

NASA Astrophysics Data System (ADS)

Zhang, Bin; Xue, Yong; Qiang, Li; Gao, Kaixong; Liu, Qiao; Yang, Baoping; Liang, Aiming; Zhang, Junyan

2017-11-01

Friction properties of carbon nanotubes have been widely studied and reported, however, the friction properties of carbon nanotubes related on state of itself. It is showing superlubricity under nanoscale, but indicates high shear adhesion as aligned carbon nanotube film. However, friction properties under high load (which is commonly in industry) of carbon nanotube films are seldom reported. In this paper, carbon nanotube films, via mechanical rubbing method, were obtained and its tribology properties were investigated at high load of 5 to 15 N. Though different couple pairs were employed, the friction coefficients of carbon nanotube films are nearly the same. Compared with bare stainless steel, friction coefficients and wear rates under carbon nanotube films lubrication reduced to, at least, 1/5 and 1/(4.3-14.5), respectively. Friction test as well as structure study were carried out to reveal the mechanism of the significant reduction wear and friction on steel surface. One can conclude that sliding and densifying of carbon nanotubes at sliding interface contribute to the sufficient decrease of friction coefficients and wear rates.

Study on Influencing Factors of Carbon Emissions from Energy Consumption of Shandong Province of China from 1995 to 2012

PubMed Central

Song, Jiekun; Song, Qing; Zhang, Dong; Lu, Youyou; Luan, Long

2014-01-01

Carbon emissions from energy consumption of Shandong province from 1995 to 2012 are calculated. Three zero-residual decomposition models (LMDI, MRCI and Shapley value models) are introduced for decomposing carbon emissions. Based on the results, Kendall coordination coefficient method is employed for testing their compatibility, and an optimal weighted combination decomposition model is constructed for improving the objectivity of decomposition. STIRPAT model is applied to evaluate the impact of each factor on carbon emissions. The results show that, using 1995 as the base year, the cumulative effects of population, per capita GDP, energy consumption intensity, and energy consumption structure of Shandong province in 2012 are positive, while the cumulative effect of industrial structure is negative. Per capita GDP is the largest driver of the increasing carbon emissions and has a great impact on carbon emissions; energy consumption intensity is a weak driver and has certain impact on carbon emissions; population plays a weak driving role, but it has the most significant impact on carbon emissions; energy consumption structure is a weak driver of the increasing carbon emissions and has a weak impact on carbon emissions; industrial structure has played a weak inhibitory role, and its impact on carbon emissions is great. PMID:24977216

Clustering stocks using partial correlation coefficients

NASA Astrophysics Data System (ADS)

Jung, Sean S.; Chang, Woojin

2016-11-01

A partial correlation analysis is performed on the Korean stock market (KOSPI). The difference between Pearson correlation and the partial correlation is analyzed and it is found that when conditioned on the market return, Pearson correlation coefficients are generally greater than those of the partial correlation, which implies that the market return tends to drive up the correlation between stock returns. A clustering analysis is then performed to study the market structure given by the partial correlation analysis and the members of the clusters are compared with the Global Industry Classification Standard (GICS). The initial hypothesis is that the firms in the same GICS sector are clustered together since they are in a similar business and environment. However, the result is inconsistent with the hypothesis and most clusters are a mix of multiple sectors suggesting that the traditional approach of using sectors to determine the proximity between stocks may not be sufficient enough to diversify a portfolio.

Preliminary quantification of the permeability, solubility and diffusion coefficients of major aroma compounds present in herbs through various plastic packaging materials.

PubMed

Leelaphiwat, Pattarin; Auras, Rafael A; Burgess, Gary J; Harte, Janice B; Chonhenchob, Vanee

2018-03-01

Aroma permeation through packaging material is an important factor when designing a package for food products. The masses of aroma compounds permeating through films over time were measured at 25 °C using a quasi-isostatic system. A model was proposed for estimating the permeability coefficients (P) of key aroma compounds present in fresh herbs (i.e. eucalyptol, estragole, linalool and citral) through major plastic films used by the food industry [i.e. low-density polyethylene (LDPE), polypropylene (PP), nylon (Nylon), polyethylene terephthalate (PET), metalised-polyethylene terephthalate (MPET) and poly(lactic acid) (PLA)]. Solubility coefficients (S) were estimated from the amount of aroma compound sorbed in the films. Diffusion coefficients (D) were estimated following from the relation P = D*S. P and D for all four aroma compounds were highest in LDPE, except for eucalyptol, which P was slightly higher in PLA. The solubility coefficients and contact angles were highest in PLA suggesting the highest affinity of PLA to these aroma compounds. The theoretical solubility parameters were correlated with the solubility coefficients for estragole and citral, but not for eucalyptol and linalool. The preliminary P, D and S of eucalyptol, estragole, linalool and citral through LDPE, PP, Nylon, PET, MPET and PLA can be useful in selecting the proper packaging material for preserving these specific aroma compounds in food products and can potentially be used for estimating the shelf life of food products based on aroma loss. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Sectoral output, energy use, and CO2 emission in middle-income countries.

PubMed

Sohag, Kazi; Al Mamun, Md; Uddin, Gazi Salah; Ahmed, Ali M

2017-04-01

Middle-income countries are currently undergoing massive structural changes towards more industrialized economies. In this paper, we carefully examine the impact of these transformations on the environmental quality of middle-income countries. Specifically, we examine the role of sector value addition to GDP on CO 2 emission nexus for middle-income economies controlling for the effects of population growth, energy use, and trade openness. Using recently developed panel methods that consider cross-sectional dependence and allow for heterogeneous slope coefficients, we show that energy use and growth of industrial and service sectors positively explain CO 2 emissions in middle-income economies. We also find that population growth is insignificantly associated with CO 2 emission. Hence, our paper provides a solid ground for developing a sustainable and pro-growth policy for middle-income countries.

Modeling and Simulations on the Intramural Thermoelectric Generator of Lower-Re-fluid

NASA Astrophysics Data System (ADS)

Zhang, Zheng; Zheng, Ding; Chen, Yushan

The thermoelectric conversion with lower Renault number (Re) fluid, such as waste heat from industry boiler, and engine's circled cooling water, which can be designed as intramural generator structure. In this research, a thermoelectric project analysis model and the description of an intensified system are presented, its generator with the aligned or staggered platoon structure has strengthened heat-transfer property, and the heat convection coefficient ratio has increased times than plain tube; For the fluid kinetic energy's loss is influenced by the whirlpool, the pressure difference is several hundred Pa level which changes along with geometric parameters of transform components; what's more, heat transfer area increase distinctly under the same generator volume, which has built the foundation for the enhancement output electric power.

Experimental assessment of the influence of welding process parameters on Lamb wave transmission across ultrasonically welded thermoplastic composite joints

NASA Astrophysics Data System (ADS)

Ochôa, Pedro; Fernandez Villegas, Irene; Groves, Roger M.; Benedictus, Rinze

2018-01-01

One of the advantages of thermoplastic composites relative to their thermoset counterparts is the possibility of assembling components through welding. Ultrasonic welding in particular is very promising for industrialization. However, uncertainty in the fatigue and fracture behaviour of composites is still an obstacle to the full utilisation of these materials. Health monitoring is then of vital importance, and Lamb wave techniques have been widely recognised as some of the most promising approaches for that end. This paper presents the first experimental study about the influence of welding travel on the transmission of Lamb waves across ultrasonically welded thermoplastic composite joints in single-lap configuration. The main aim of this research is to start to understand how guided waves interact with the internal structure of ultrasonic welds, so that benign, manufacturing-related structural features can be distinguished from damaging ones in signal interpretation. The power transmission coefficient and the correlation coefficient proved to be suitable for analysing the wave propagation phenomena, allowing quantitative identification of small variations of weld-line thickness and intermolecular diffusion at the weld interface. The conclusions are used to develop a tentative damage detection criterion which can later on assist the design of a Lamb wave based structural health monitoring system for thermoplastic composite structures. The Lamb wave test results are backed up by phased-array inspections, which also provide some extra insight on the internal structure of ultrasonic welds.

Economic-environmental modeling of point source pollution in Jefferson County, Alabama, USA.

PubMed

Kebede, Ellene; Schreiner, Dean F; Huluka, Gobena

2002-05-01

This paper uses an integrated economic-environmental model to assess the point source pollution from major industries in Jefferson County, Northern Alabama. Industrial expansion generates employment, income, and tax revenue for the public sector; however, it is also often associated with the discharge of chemical pollutants. Jefferson County is one of the largest industrial counties in Alabama that experienced smog warnings and ambient ozone concentration, 1996-1999. Past studies of chemical discharge from industries have used models to assess the pollution impact of individual plants. This study, however, uses an extended Input-Output (I-O) economic model with pollution emission coefficients to assess direct and indirect pollutant emission for several major industries in Jefferson County. The major findings of the study are: (a) the principal emission by the selected industries are volatile organic compounds (VOC) and these contribute to the ambient ozone concentration; (b) the direct and indirect emissions are significantly higher than the direct emission by some industries, indicating that an isolated analysis will underestimate the emission by an industry; (c) while low emission coefficient industries may suggest industry choice they may also emit the most hazardous chemicals. This study is limited by the assumptions made, and the data availability, however it provides a useful analytical tool for direct and cumulative emission estimation and generates insights on the complexity in choice of industries.

Photoelastic response of permanently densified oxide glasses

NASA Astrophysics Data System (ADS)

Bechgaard, Tobias K.; Mauro, John C.; Thirion, Lynn M.; Rzoska, Sylwester J.; Bockowski, Michal; Smedskjaer, Morten M.

2017-05-01

The stress-induced birefringence (photoelastic response) in oxide glasses has important consequences for several applications, including glass for flat panel displays, chemically strengthened cover glass, and advanced optical glasses. While the effect of composition on the photoelastic response is relatively well documented, the effect of pressure has not been systematically studied. In this work, we evaluate the effect of hot isostatic compression on the photoelastic response of ten oxide glasses within two commonly used industrial glass families: aluminosilicates and boroaluminosilicates. Hot isostatic compression generally results in decreasing modifier-oxygen bond lengths and increasing network-former coordination numbers. These structural changes should lead to an increase in the stress optic coefficient (C) according to the model of Zwanziger et al., which can successfully predict the composition and structure dependence of C. However, in compressed glasses, we observe the opposite trend, viz., a decrease in the stress optic coefficient as a result of pressurization. We discuss this result based on measured changes in refractive index and elastic moduli within the context of atomic and lattice effects, building on the pioneering work of Mueller. We propose that the pressure-induced decrease in C is a result of changes in the shear modulus due to underlying topological changes in the glass network.

Rational design and synthesis of an orally bioavailable peptide guided by NMR amide temperature coefficients

PubMed Central

Wang, Conan K.; Northfield, Susan E.; Colless, Barbara; Chaousis, Stephanie; Hamernig, Ingrid; Lohman, Rink-Jan; Nielsen, Daniel S.; Schroeder, Christina I.; Liras, Spiros; Price, David A.; Fairlie, David P.; Craik, David J.

2014-01-01

Enhancing the oral bioavailability of peptide drug leads is a major challenge in drug design. As such, methods to address this challenge are highly sought after by the pharmaceutical industry. Here, we propose a strategy to identify appropriate amides for N-methylation using temperature coefficients measured by NMR to identify exposed amides in cyclic peptides. N-methylation effectively caps these amides, modifying the overall solvation properties of the peptides and making them more membrane permeable. The approach for identifying sites for N-methylation is a rapid alternative to the elucidation of 3D structures of peptide drug leads, which has been a commonly used structure-guided approach in the past. Five leucine-rich peptide scaffolds are reported with selectively designed N-methylated derivatives. In vitro membrane permeability was assessed by parallel artificial membrane permeability assay and Caco-2 assay. The most promising N-methylated peptide was then tested in vivo. Here we report a novel peptide (15), which displayed an oral bioavailability of 33% in a rat model, thus validating the design approach. We show that this approach can also be used to explain the notable increase in oral bioavailability of a somatostatin analog. PMID:25416591

Predictive model to describe water migration in cellular solid foods during storage.

PubMed

Voogt, Juliën A; Hirte, Anita; Meinders, Marcel B J

2011-11-01

Water migration in cellular solid foods during storage causes loss of crispness. To improve crispness retention, physical understanding of this process is needed. Mathematical models are suitable tools to gain this physical knowledge. Water migration in cellular solid foods involves migration through both the air cells and the solid matrix. For systems in which the water migration distance is large compared with the cell wall thickness of the solid matrix, the overall water flux through the system is dominated by the flux through the air. For these systems, water migration can be approximated well by a Fickian diffusion model. The effective diffusion coefficient can be expressed in terms of the material properties of the solid matrix (i.e. the density, sorption isotherm and diffusion coefficient of water in the solid matrix) and the morphological properties of the cellular structure (i.e. water vapour permeability and volume fraction of the solid matrix). The water vapour permeability is estimated from finite element method modelling using a simplified model for the cellular structure. It is shown that experimentally observed dynamical water profiles of bread rolls that differ in crust permeability are predicted well by the Fickian diffusion model. Copyright © 2011 Society of Chemical Industry.

A social network's changing statistical properties and the quality of human innovation

NASA Astrophysics Data System (ADS)

Uzzi, Brian

2008-06-01

We examined the entire network of creative artists that made Broadway musicals, in the post-War period, a collaboration network of international acclaim and influence, with an eye to investigating how the network's structural features condition the relationship between individual artistic talent and the success of their musicals. Our findings show that some of the evolving topographical qualities of degree distributions, path lengths and assortativity are relatively stable with time even as collaboration patterns shift, which suggests their changes are only minimally associated with the ebb and flux of the success of new productions. In contrast, the clustering coefficient changed substantially over time and we found that it had a nonlinear association with the production of financially and artistically successful shows. When the clustering coefficient ratio is low or high, the financial and artistic success of the industry is low, while an intermediate level of clustering is associated with successful shows. We supported these findings with sociological theory on the relationship between social structure and collaboration and with tests of statistical inference. Our discussion focuses on connecting the statistical properties of social networks to their performance and the performance of the actors embedded within them.

Rational design and synthesis of an orally bioavailable peptide guided by NMR amide temperature coefficients.

PubMed

Wang, Conan K; Northfield, Susan E; Colless, Barbara; Chaousis, Stephanie; Hamernig, Ingrid; Lohman, Rink-Jan; Nielsen, Daniel S; Schroeder, Christina I; Liras, Spiros; Price, David A; Fairlie, David P; Craik, David J

2014-12-09

Enhancing the oral bioavailability of peptide drug leads is a major challenge in drug design. As such, methods to address this challenge are highly sought after by the pharmaceutical industry. Here, we propose a strategy to identify appropriate amides for N-methylation using temperature coefficients measured by NMR to identify exposed amides in cyclic peptides. N-methylation effectively caps these amides, modifying the overall solvation properties of the peptides and making them more membrane permeable. The approach for identifying sites for N-methylation is a rapid alternative to the elucidation of 3D structures of peptide drug leads, which has been a commonly used structure-guided approach in the past. Five leucine-rich peptide scaffolds are reported with selectively designed N-methylated derivatives. In vitro membrane permeability was assessed by parallel artificial membrane permeability assay and Caco-2 assay. The most promising N-methylated peptide was then tested in vivo. Here we report a novel peptide (15), which displayed an oral bioavailability of 33% in a rat model, thus validating the design approach. We show that this approach can also be used to explain the notable increase in oral bioavailability of a somatostatin analog.

Edge Diffraction Coefficients around Critical Rays

NASA Astrophysics Data System (ADS)

Fradkin, L.; Harmer, M.; Darmon, M.

2014-04-01

The classical GTD (Geometrical Theory of Diffraction) gives a recipe, based on high-frequency asymptotics, for calculating edge diffraction coefficients in the geometrical regions where only diffracted waves propagate. The Uniform GTD extends this recipe to transition zones between irradiated and silent regions, known as penumbra. For many industrial materials, e.g. steels, and frequencies utlized in industrial ultrasonic transducers, that is, around 5 MHz, asymptotics suggested for description of geometrical regions supporting the head waves or transition regions surrounding their boundaries, known as critical rays, prove unsatisfactory. We present a numerical extension of GTD, which is based on a regularized, variable step Simpson's method for evaluating the edge diffraction coefficients in the regions of interference between head waves, diffracted waves and/or reflected waves. In mathematical terms, these are the regions of coalescence of three critical points - a branch point, stationary point and/or pole, respectively. We show that away from the shadow boundaries, near the critical rays the GTD still produces correct values of the edge diffraction coefficients.

Numerical Simulation of the Working Process in the Twin Screw Vacuum Pump

NASA Astrophysics Data System (ADS)

Lu, Yang; Fu, Yu; Guo, Bei; Fu, Lijuan; Zhang, Qingqing; Chen, Xiaole

2017-08-01

Twin screw vacuum pumps inherit the advantages of screw machinery, such as high reliability, stable medium conveying, small vibration, simple and compact structures, convenient operation, etc, which have been widely used in petrochemical and air industry. On the basis of previous studies, this study analyzed the geometric features of variable pitch of the twin screw vacuum pump such as the sealing line, the meshing line and the volume between teeth. The mathematical model of numerical simulation of the twin screw vacuum pump was established. The leakage paths of the working volume including the sealing line and the addendum arc were comprehensively considered. The corresponding simplified geometric model of leakage flow was built up for different leak paths and the flow coefficients were calculated. The flow coefficient value range of different leak paths was given. The results showed that the flow coefficient of different leak paths can be taken as constant value for the studied geometry. The analysis of recorded indicator diagrams showed that the increasing rotational speed can dramatically decrease the exhaust pressure and the lower rotational speed can lead to over-compression. The pressure of the isentropic process which was affected by leakage was higher than the theoretical process.

A Novel Acoustic Sensor Approach to Classify Seeds Based on Sound Absorption Spectra

PubMed Central

Gasso-Tortajada, Vicent; Ward, Alastair J.; Mansur, Hasib; Brøchner, Torben; Sørensen, Claus G.; Green, Ole

2010-01-01

A non-destructive and novel in situ acoustic sensor approach based on the sound absorption spectra was developed for identifying and classifying different seed types. The absorption coefficient spectra were determined by using the impedance tube measurement method. Subsequently, a multivariate statistical analysis, i.e., principal component analysis (PCA), was performed as a way to generate a classification of the seeds based on the soft independent modelling of class analogy (SIMCA) method. The results show that the sound absorption coefficient spectra of different seed types present characteristic patterns which are highly dependent on seed size and shape. In general, seed particle size and sphericity were inversely related with the absorption coefficient. PCA presented reliable grouping capabilities within the diverse seed types, since the 95% of the total spectral variance was described by the first two principal components. Furthermore, the SIMCA classification model based on the absorption spectra achieved optimal results as 100% of the evaluation samples were correctly classified. This study contains the initial structuring of an innovative method that will present new possibilities in agriculture and industry for classifying and determining physical properties of seeds and other materials. PMID:22163455

Experimental Study of Heat Transfer Performance of Polysilicon Slurry Drying Process

NASA Astrophysics Data System (ADS)

Wang, Xiaojing; Ma, Dongyun; Liu, Yaqian; Wang, Zhimin; Yan, Yangyang; Li, Yuankui

2016-12-01

In recent years, the growth of the solar energy photovoltaic industry has greatly promoted the development of polysilicon. However, there has been little research into the slurry by-products of polysilicon production. In this paper the thermal performance of polysilicon slurry was studied in an industrial drying process with a twin-screw horizontal intermittent dryer. By dividing the drying process into several subunits, the parameters of each unit could be regarded as constant in that period. The time-dependent changes in parameters including temperature, specific heat and evaporation enthalpy were plotted. An equation for the change in the heat transfer coefficient over time was calculated based on heat transfer equations. The concept of a distribution coefficient was introduced to reflect the influence of stirring on the heat transfer area. The distribution coefficient ranged from 1.2 to 1.7 and was obtained with the fluid simulation software FLUENT, which simplified the calculation of heat transfer area during the drying process. These experimental data can be used to guide the study of polysilicon slurry drying and optimize the design of dryers for industrial processes.

Structural, Functional and Evolutionary Aspects of Seed Globulins.

PubMed

Kesari, Pooja; Neetu; Sharma, Anchal; Katiki, Madhusudhanarao; Kumar, Pramod; Gurjar, Bhola R; Tomar, Shailly; Sharma, Ashwani K; Kumar, Pravindra

2017-01-01

Globulins are a major class of seed storage proteins which were thought to be enzymatically inactive. These proteins belong to the most ancient cupin superfamily. They can be graded into 11S legumin type and 7S vicilin type based on their sedimentation coefficients. Members from both classes share structural homology are thought to have evolved from either one-domain germin predecessor by duplication or by horizontal gene transfer of two-domain gene from bacteria to eukaryotes. Globulins are known to define the nutritional quality of the seeds, however, they are also involved in sucrose binding, desiccation, defense against microbes, hormone binding and oxidative stress etc. Major drawback with globulins is their tendency to bind to IgE. Studying structural-functional behavior of such protein can help in modifying proteins for enhanced functionality in food processing industries. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Industrial entrepreneurial network: Structural and functional analysis

NASA Astrophysics Data System (ADS)

Medvedeva, M. A.; Davletbaev, R. H.; Berg, D. B.; Nazarova, J. J.; Parusheva, S. S.

2016-12-01

Structure and functioning of two model industrial entrepreneurial networks are investigated in the present paper. One of these networks is forming when implementing an integrated project and consists of eight agents, which interact with each other and external environment. The other one is obtained from the municipal economy and is based on the set of the 12 real business entities. Analysis of the networks is carried out on the basis of the matrix of mutual payments aggregated over the certain time period. The matrix is created by the methods of experimental economics. Social Network Analysis (SNA) methods and instruments were used in the present research. The set of basic structural characteristics was investigated: set of quantitative parameters such as density, diameter, clustering coefficient, different kinds of centrality, and etc. They were compared with the random Bernoulli graphs of the corresponding size and density. Discovered variations of random and entrepreneurial networks structure are explained by the peculiarities of agents functioning in production network. Separately, were identified the closed exchange circuits (cyclically closed contours of graph) forming an autopoietic (self-replicating) network pattern. The purpose of the functional analysis was to identify the contribution of the autopoietic network pattern in its gross product. It was found that the magnitude of this contribution is more than 20%. Such value allows using of the complementary currency in order to stimulate economic activity of network agents.

Numerical Simulation of Heat Transfer in Porous Metals for Cooling Applications

NASA Astrophysics Data System (ADS)

Gauna, Edgar Avalos; Zhao, Yuyuan

2017-08-01

Porous metals have low densities and novel physical, mechanical, thermal, electrical, and acoustic properties. Hence, they have attracted a large amount of interest over the last few decades. One of their applications is for thermal management in the electronics industry because of their fluid permeability and thermal conductivity. The heat transfer capability is achieved by the interaction between the internal channels within the porous metal and the coolant flowing through them. This paper studies the fluid flow and heat transfer in open-cell porous metals manufactured by space holder methods by numerical simulation using software ANSYS Fluent. A 3D geometric model of the porous structure was created based on the face-centered-cubic arrangement of spheres linked by cylinders. This model allows for different combinations of pore parameters including a wide range of porosity (50 to 80 pct), pore size (400 to 1000 µm), and metal particle size (10 to 75 µm). In this study, water was used as the coolant and copper was selected as the metal matrix. The flow rate was varied in the Darcian and Forchheimer's regimes. The permeability, form drag coefficient, and heat transfer coefficient were calculated under a range of conditions. The numerical results showed that permeability increased whereas the form drag coefficient decreased with porosity. Both permeability and form drag coefficient increased with pore size. Increasing flow rate and decreasing porosity led to better heat transfer performance.

Forecast of future aviation fuels: The model

NASA Technical Reports Server (NTRS)

Ayati, M. B.; Liu, C. Y.; English, J. M.

1981-01-01

A conceptual models of the commercial air transportation industry is developed which can be used to predict trends in economics, demand, and consumption. The methodology is based on digraph theory, which considers the interaction of variables and propagation of changes. Air transportation economics are treated by examination of major variables, their relationships, historic trends, and calculation of regression coefficients. A description of the modeling technique and a compilation of historic airline industry statistics used to determine interaction coefficients are included. Results of model validations show negligible difference between actual and projected values over the twenty-eight year period of 1959 to 1976. A limited application of the method presents forecasts of air tranportation industry demand, growth, revenue, costs, and fuel consumption to 2020 for two scenarios of future economic growth and energy consumption.

Development of a Supported Emulsion Liquid Membrane System for Propionic Acid Separation in a Microgravity Environment

NASA Technical Reports Server (NTRS)

Li, Jin; Hu, Shih-Yao B.; Wiencek, John M.

2001-01-01

Perstractive fermentation is a good way to increase the productivity of bioreactors. Using Propionibacteria as the model system, the feasibility of using supported emulsion liquid membrane (SELM) for perstractive fermentation is assessed in this study. Five industrial solvents were considered as the solvent for preparing the SELM. The more polar a solvent is, the higher the partition coefficient. However, toxicity of a solvent also increases with its polarity. CO-1055 (industrial decanol/octanol blend) has the highest partition coefficient toward propionic acid among the solvents that has no molecular toxicity toward Propionibacteria. A preliminary extraction study was conducted using tetradecane as solvent in a hydrophobic hollow fiber contactor. The result confirmed that SELM eliminates the equilibrium limitation of conventional liquid-liquid extraction, and allows the use of a non-toxic solvent with low partition coefficient.

School Facilities and Student Achievement in Industrial Countries: Evidence from the TIMSS

ERIC Educational Resources Information Center

Hopland, Arnt O.

2013-01-01

This paper studies the link between school facilities (buildings and grounds) and student achievement in eight countries using data from the TIMSS 2003 database. The results indicate a negative relationship, but the estimated coefficients are mainly insignificant. Interestingly, the coefficients differ heavily across countries. Whereas there seem…

Measurement and analysis of the mannitol partition coefficient in sucrose crystallization under simulated industrial conditions

USDA-ARS?s Scientific Manuscript database

Mannitol is a major deterioration product of Leuconstoc mesenteroides bacterial deterioration of both sugarcane and sugar beet. The effect of crystallization conditions on the mannitol partition coefficient (Keff) between impure sucrose syrup and crystal has been investigated in a batch laboratory c...

Synthesis/literature review for determining structural layer coefficients (SLC) of bases.

DOT National Transportation Integrated Search

2014-12-01

FDOTs current method of determining a base material structural layer coefficient (SLC) is detailed in the : Materials Manual, Chapter 2.1, Structural Layer Coefficients for Flexible Pavement Base Materials. : Currently, any new base material not a...

Influence of the pressure dependent coefficient of friction on deep drawing springback predictions

NASA Astrophysics Data System (ADS)

Gil, Imanol; Galdos, Lander; Mendiguren, Joseba; Mugarra, Endika; Sáenz de Argandoña, Eneko

2016-10-01

This research studies the effect of considering an advanced variable friction coefficient on the springback prediction of stamping processes. Traditional constant coefficient of friction considerations are being replaced by more advanced friction coefficient definitions. The aim of this work is to show the influence of defining a pressure dependent friction coefficient on numerical springback predictions of a DX54D mild steel, a HSLA380 and a DP780 high strength steel. The pressure dependent friction model of each material was fitted to the experimental data obtained by Strip Drawing tests. Then, these friction models were implemented in a numerical simulation of a drawing process of an industrial automotive part. The results showed important differences between defining a pressure dependent friction coefficient or a constant friction coefficient.

Network analysis of a financial market based on genuine correlation and threshold method

NASA Astrophysics Data System (ADS)

Namaki, A.; Shirazi, A. H.; Raei, R.; Jafari, G. R.

2011-10-01

A financial market is an example of an adaptive complex network consisting of many interacting units. This network reflects market’s behavior. In this paper, we use Random Matrix Theory (RMT) notion for specifying the largest eigenvector of correlation matrix as the market mode of stock network. For a better risk management, we clean the correlation matrix by removing the market mode from data and then construct this matrix based on the residuals. We show that this technique has an important effect on correlation coefficient distribution by applying it for Dow Jones Industrial Average (DJIA). To study the topological structure of a network we apply the removing market mode technique and the threshold method to Tehran Stock Exchange (TSE) as an example. We show that this network follows a power-law model in certain intervals. We also show the behavior of clustering coefficients and component numbers of this network for different thresholds. These outputs are useful for both theoretical and practical purposes such as asset allocation and risk management.

Effects of global financial crisis on network structure in a local stock market

NASA Astrophysics Data System (ADS)

Nobi, Ashadun; Maeng, Seong Eun; Ha, Gyeong Gyun; Lee, Jae Woo

2014-08-01

This study considers the effects of the 2008 global financial crisis on threshold networks of a local Korean financial market around the time of the crisis. Prices of individual stocks belonging to KOSPI 200 (Korea Composite Stock Price Index 200) are considered for three time periods, namely before, during, and after the crisis. Threshold networks are constructed from fully connected cross-correlation networks, and thresholds of cross-correlation coefficients are assigned to obtain threshold networks. At the high threshold, only one large cluster consisting of firms in the financial sector, heavy industry, and construction is observed during the crisis. However, before and after the crisis, there are several fragmented clusters belonging to various sectors. The power law of the degree distribution in threshold networks is observed within the limited range of thresholds. Threshold networks are fatter during the crisis than before or after the crisis. The clustering coefficient of the threshold network follows the power law in the scaling range.

Concentration in the Greek private hospital sector: a descriptive analysis.

PubMed

Boutsioli, Zoe

2007-07-01

Over the last 20 years, governments all around the world have attempted to boost the role of market and competition in health care industries in order to increase efficiency and reduce costs. The increased competition and the significant implications on costs and prices of health care services resulted in health care industries being transformed. Large firms are merging and acquiring other firms. If this trend continues, few firms will dominate the health care markets. In this study, I use the simple concentration ratio (CR) for the largest 4, 8 and 20 companies to measure the concentration of Greek private hospitals during the period 1997-2004. Also, the Gini coefficient for inequality is used. For the two different categories of hospitals used (a) general and neuropsychiatric and (b) obstetric/gynaecological it is evident that the top four firms of the first category accounted for 43% of sales in 1997, and 52% in 2004, while the four largest firms of the second category accounted for almost 83% in 1997, and 81% in 2004. Also, the Gini coefficient increases over the 8-year period examined from 0.69 in 1997 to 0.82 in 2004. It explains that the market of the private health care services becomes less equal in the sense that fewer private hospitals and clinics hold more and more of the share of the total sales. From a cross-industry analysis it is clear that the private hospital sector has the highest concentration rate. Finally, it appears that the market structure of the private hospitals in Greece resembles more closely to an oligopoly rather than a monopolistic competition, since very few firms dominate the market.

Emergy-based comparative analysis of energy intensity in different industrial systems.

PubMed

Liu, Zhe; Geng, Yong; Wang, Hui; Sun, Lu; Ma, Zhixiao; Tian, Xu; Yu, Xiaoman

2015-12-01

With the rapid economic development, energy consumption of China has been the second place in the world next to the USA. Usually, measuring energy consumption intensity or efficiency applies heat unit which is joule per gross domestic production (GDP) or coal equivalent per GDP. However, this measuring approach is only oriented by the conversion coefficient of heat combustion which does not match the real value of the materials during their formation in the ecological system. This study applied emergy analysis to evaluate the energy consumption intensity to fill this gap. Emergy analysis is considered as a bridge between ecological system and economic system, which can evaluate the contribution of ecological products and services as well as the load placed on environmental systems. In this study, emergy indicator for performing energy consumption intensity of primary energy was proposed. Industrial production is assumed as the main contributor of energy consumption compared to primary and tertiary industries. Therefore, this study validated this method by investigating the two industrial case studies which were Dalian Economic Development Area (DEDA) and Fuzhou economic and technological area (FETA), to comparatively study on their energy consumption intensity between the different kinds of industrial systems and investigate the reasons behind the differences. The results show that primary energy consumption (PEC) of DEDA was much higher than that of FETA during 2006 to 2010 and its primary energy consumption ratio (PECR) to total emergy involvement had a dramatically decline from year 2006 to 2010. In the same time, nonrenewable energy of PEC in DEDA was also much higher than that in FETA. The reason was that industrial structure of DEDA was mainly formed by heavy industries like petro-chemistry industry, manufacturing industries, and high energy-intensive industries. However, FETA was formed by electronic business, food industry, and light industries. Although the GDP of DEDA was much higher than that of FETA, its energy intensity was higher as well. Through the 5-year development, energy consumption intensity in DEDA made a significant reduction from 3.90E+16 seJ/$ to 1.84E+16 seJ/$, which was attributed by the improvement of industrial structure, construction of eco-industrial park and circular economic industrial park. The proposed emergy indicator for demonstrating energy consumption intensity overcame the weakness that the indicator was only transformed from the heat burning. Therefore, this study shows an optional way to measure energy consumption intensity from the perspective of material ecological contribution.

Model of Silicon Refining During Tapping: Removal of Ca, Al, and Other Selected Element Groups

NASA Astrophysics Data System (ADS)

Olsen, Jan Erik; Kero, Ida T.; Engh, Thorvald A.; Tranell, Gabriella

2017-04-01

A mathematical model for industrial refining of silicon alloys has been developed for the so-called oxidative ladle refining process. It is a lumped (zero-dimensional) model, based on the mass balances of metal, slag, and gas in the ladle, developed to operate with relatively short computational times for the sake of industrial relevance. The model accounts for a semi-continuous process which includes both the tapping and post-tapping refining stages. It predicts the concentrations of Ca, Al, and trace elements, most notably the alkaline metals, alkaline earth metal, and rare earth metals. The predictive power of the model depends on the quality of the model coefficients, the kinetic coefficient, τ, and the equilibrium partition coefficient, L for a given element. A sensitivity analysis indicates that the model results are most sensitive to L. The model has been compared to industrial measurement data and found to be able to qualitatively, and to some extent quantitatively, predict the data. The model is very well suited for alkaline and alkaline earth metals which respond relatively fast to the refining process. The model is less well suited for elements such as the lanthanides and Al, which are refined more slowly. A major challenge for the prediction of the behavior of the rare earth metals is that reliable thermodynamic data for true equilibrium conditions relevant to the industrial process is not typically available in literature.

High Temperature Alkali Corrosion of Dense SN4 Coated with CMZP and Mg-Doped A21TiO5 in Coal Gas

DOE Office of Scientific and Technical Information (OSTI.GOV)

J. J. Brown; Nguyen Thierry

1997-10-01

Si3N4 heat exchangers used in industrial systems are usually operating in harsh environments. Not only is this structural material experiencing high temperatures, but it is also subjected to corrosive gases and condensed phases. Past studies have demonstrated that condensed phases severely attack Si3N4 and as a consequence, dramatically reduce its lifetime in industrial operating systems.1,2 Previous research conducted at Virginia Tech on low thermal expansion coefficient oxide ceramics,3,4,5 (Ca1-X,MgX)Zr4(PO4)6 (CMZP), and Mg-doped Al2TiO5, for structural application have shown that these two materials exhibited better resistance to alkaline corrosion than Si3N4. Thus, they were envisioned as good candidates for a protectivemore » coating on Si3N4 heat exchangers. As a result, the goal of the present work is to develop CMZP and Mg-doped Al2TiO5 protective thin films using the sol-gel process and the dip coating technique and to test their effectiveness in an alkali-containing atmosphere.« less

Psychometric properties and differential explanation of a short measure of effort-reward imbalance at work: a study of industrial workers in Germany.

PubMed

Li, Jian; Loerbroks, Adrian; Jarczok, Marc N; Schöllgen, Ina; Bosch, Jos A; Mauss, Daniel; Siegrist, Johannes; Fischer, Joachim E

2012-09-01

We test the psychometric properties of a short version of the Effort-Reward Imbalance (ERI) questionnaire in addition to testing an interaction term of this model's main components on health functioning. A self-administered survey was conducted in a sample of 2,738 industrial workers (77% men with mean age 41.6 years) from a large manufacturing company in Southern Germany. The internal consistency reliability, structural validity, and criterion validity were analyzed. Satisfactory internal consistencies of the three scales: "Effort", "reward", and "overcommitment", were obtained (Cronbach's alpha coefficients 0.77, 0.82, and 0.83, respectively). Confirmatory factor analysis showed a good model fit of the data with the theoretical structure (AGFI = 0.94, RMSEA = 0.060). Evidence of criterion validity was demonstrated. Importantly, a significant synergistic interaction effect of ERI and overcommitment on poor mental health functioning was observed (odds ratio 6.74 (95% CI 5.32-8.52); synergy index 1.78 (95% CI 1.25-2.55)). This short version of the ERI questionnaire is a reliable and valid tool for epidemiological research on occupational health. Copyright © 2012 Wiley Periodicals, Inc.

Factor Scores, Structure Coefficients, and Communality Coefficients

ERIC Educational Resources Information Center

Goodwyn, Fara

2012-01-01

This paper presents heuristic explanations of factor scores, structure coefficients, and communality coefficients. Common misconceptions regarding these topics are clarified. In addition, (a) the regression (b) Bartlett, (c) Anderson-Rubin, and (d) Thompson methods for calculating factor scores are reviewed. Syntax necessary to execute all four…

Investigation of a Bio-Inspired Liner Concept

NASA Technical Reports Server (NTRS)

Koch, L. Danielle

2017-01-01

Four samples of natural reeds, Phragmites australis, were tested in the NASA Langley and Glenn Normal Incidence Impedance Tubes in order to experimentally determine the acoustic absorption coefficients as a function of frequency from 400 to 3000 Hz. Six samples that mimicked the geometry of the assemblies of natural reeds were also designed and additively manufactured from ASA thermoplastic and tested. Results indicate that structures can be manufactured of synthetic materials that mimic the geometry and the low frequency acoustic absorption of natural reeds. This accomplishment demonstrates that a new class of structures can now be considered for a wide range of industrial products that need thin, lightweight, broadband acoustic absorption effective at frequencies below 1000 Hz. Aircraft engine acoustic liners and aircraft cabin acoustic liners, in particular, are two aviation applications that might benefit from further development of this concept.

Investigation on an ammonia supply system for flue gas denitrification of low-speed marine diesel

PubMed Central

Yuan, Han; Zhao, Jian; Mei, Ning

2017-01-01

Low-speed marine diesel flue gas denitrification is in great demand in the ship transport industry. This research proposes an ammonia supply system which can be used for flue gas denitrification of low-speed marine diesel. In this proposed ammonia supply system, ammonium bicarbonate is selected as the ammonia carrier to produce ammonia and carbon dioxide by thermal decomposition. The diesel engine exhaust heat is used as the heating source for ammonium bicarbonate decomposition and ammonia gas desorption. As the ammonium bicarbonate decomposition is critical to the proper operation of this system, effects have been observed to reveal the performance of the thermal decomposition chamber in this paper. A visualization experiment for determination of the single-tube heat transfer coefficient and simulation of flow and heat transfer in two structures is conducted; the decomposition of ammonium bicarbonate is simulated by ASPEN PLUS. The results show that the single-tube heat transfer coefficient is 1052 W m2 °C−1; the thermal decomposition chamber fork-type structure gets a higher heat transfer compared with the row-type. With regard to the simulation of ammonium bicarbonate thermal decomposition, the ammonia production is significantly affected by the reaction temperature and the mass flow rate of the ammonium bicarbonate input. PMID:29308269

Investigation on an ammonia supply system for flue gas denitrification of low-speed marine diesel

NASA Astrophysics Data System (ADS)

Huang, Xiankun; Yuan, Han; Zhao, Jian; Mei, Ning

2017-12-01

Low-speed marine diesel flue gas denitrification is in great demand in the ship transport industry. This research proposes an ammonia supply system which can be used for flue gas denitrification of low-speed marine diesel. In this proposed ammonia supply system, ammonium bicarbonate is selected as the ammonia carrier to produce ammonia and carbon dioxide by thermal decomposition. The diesel engine exhaust heat is used as the heating source for ammonium bicarbonate decomposition and ammonia gas desorption. As the ammonium bicarbonate decomposition is critical to the proper operation of this system, effects have been observed to reveal the performance of the thermal decomposition chamber in this paper. A visualization experiment for determination of the single-tube heat transfer coefficient and simulation of flow and heat transfer in two structures is conducted; the decomposition of ammonium bicarbonate is simulated by ASPEN PLUS. The results show that the single-tube heat transfer coefficient is 1052 W m2 °C-1; the thermal decomposition chamber fork-type structure gets a higher heat transfer compared with the row-type. With regard to the simulation of ammonium bicarbonate thermal decomposition, the ammonia production is significantly affected by the reaction temperature and the mass flow rate of the ammonium bicarbonate input.

Electronic and thermal transport study of sinusoidally corrugated nanowires aiming to improve thermoelectric efficiency.

PubMed

Park, K H; Martin, P N; Ravaioli, U

2016-01-22

Improvement of thermoelectric efficiency has been very challenging in the solid-state industry due to the interplay among transport coefficients which measure the efficiency. In this work, we modulate the geometry of nanowires to interrupt thermal transport with causing only a minimal impact on electronic transport properties, thereby maximizing the thermoelectric power generation. As it is essential to scrutinize comprehensively both electronic and thermal transport behaviors for nano-scale thermoelectric devices, we investigate the Seebeck coefficient, the electrical conductance, and the thermal conductivity of sinusoidally corrugated silicon nanowires and eventually look into an enhancement of the thermoelectric figure-of-merit [Formula: see text] from the modulated nanowires over typical straight nanowires. A loss in the electronic transport coefficient is calculated with the recursive Green function along with the Landauer formalism, and the thermal transport is simulated with the molecular dynamics. In contrast to a small influence on the thermopower and the electrical conductance of the geometry-modulated nanowires, a large reduction of the thermal conductivity yields an enhancement of the efficiency by 10% to 35% from the typical nanowires. We find that this approach can be easily extended to various structures and materials as we consider the geometrical modulation as a sole source of perturbation to the system.

Spatial Variability and Distribution of the Metals in Surface Runoff in a Nonferrous Metal Mine

PubMed Central

Ren, Bozhi; Chen, Yangbo; Zhu, Guocheng; Wang, Zhenghua; Zheng, Xie

2016-01-01

The spatial variation and distribution features of the metals tested in the surface runoff in Xikuangshan Bao Daxing miming area were analyzed by combining statistical methods with a geographic information system (GIS). The results showed that the maximum concentrations of those five kinds of the metals (Sb, Zn, Cu, Pb, and Cd) in the surface runoff of the antimony mining area were lower than the standard value except the concentration of metal Ni. Their concentrations were 497.1, 2.0, 1.8, 22.2, and 22.1 times larger than the standard value, respectively. This metal pollution was mainly concentrated in local areas, which were seriously polluted. The variation coefficient of Sb, Zn, Cu, Ni, Pb, and Cd was between 0.4 to 0.6, wherein the Sb's spatial variability coefficient is 50.56%, indicating a strong variability. Variation coefficients of the rest of metals were less than 50%, suggesting a moderate variability. The spatial structure analysis showed that the squared correlation coefficient (R 2) of the models fitting for Sb, Zn, Cu, Ni, Pb, and Cd was between 0.721 and 0.976; the ratio of the nugget value (C 0) to the abutment value (C + C 0) was between 0.0767 and 0.559; the semivariogram of Sb, Zn, Ni, and Pb was in agreement with a spherical model, while semivariogram of Cu and Cd was in agreement with Gaussian model, and both had a strong spatial correlation. The trend and spatial distribution indicated that those pollution distributions resulting from Ni, Pb, and Cd are similar, mainly concentrated in both ends of north and south in eastern part. The main reasons for the pollution were attributed to the residents living, transportation, and industrial activities; the Sb distribution was concentrated mainly in the central part, of which the pollution was assigned to the mining and the industrial activity; the pollution distributions of Zn and Cu were similar, mainly concentrated in both ends of north and south as well as in west; the sources of the metals were widely distributed. PMID:27069713

Partitioning and lipophilicity in quantitative structure-activity relationships.

PubMed Central

Dearden, J C

1985-01-01

The history of the relationship of biological activity to partition coefficient and related properties is briefly reviewed. The dominance of partition coefficient in quantitation of structure-activity relationships is emphasized, although the importance of other factors is also demonstrated. Various mathematical models of in vivo transport and binding are discussed; most of these involve partitioning as the primary mechanism of transport. The models describe observed quantitative structure-activity relationships (QSARs) well on the whole, confirming that partitioning is of key importance in in vivo behavior of a xenobiotic. The partition coefficient is shown to correlate with numerous other parameters representing bulk, such as molecular weight, volume and surface area, parachor and calculated indices such as molecular connectivity; this is especially so for apolar molecules, because for polar molecules lipophilicity factors into both bulk and polar or hydrogen bonding components. The relationship of partition coefficient to chromatographic parameters is discussed, and it is shown that such parameters, which are often readily obtainable experimentally, can successfully supplant partition coefficient in QSARs. The relationship of aqueous solubility with partition coefficient is examined in detail. Correlations are observed, even with solid compounds, and these can be used to predict solubility. The additive/constitutive nature of partition coefficient is discussed extensively, as are the available schemes for the calculation of partition coefficient. Finally the use of partition coefficient to provide structural information is considered. It is shown that partition coefficient can be a valuable structural tool, especially if the enthalpy and entropy of partitioning are available. PMID:3905374

Determination of the mass-transfer coefficient in liquid phase in a stream-bubble contact device

NASA Astrophysics Data System (ADS)

Dmitriev, A. V.; Dmitrieva, O. S.; Madyshev, I. N.

2016-09-01

One of the most effective energy saving technologies is the improvement of existing heat and mass exchange units. A stream-bubble contact device is designed to enhance the operation efficiency of heat and mass exchange units. The stages of the stream-bubble units that are proposed by the authors for the decarbonization process comprise contact devices with equivalent sizes, whose number is determined by the required performance of a unit. This approach to the structural design eliminates the problems that arise upon the transition from laboratory samples to industrial facilities and makes it possible to design the units of any required performance without a decrease in the effectiveness of mass exchange. To choose the optimal design that provides the maximum effectiveness of the mass-exchange processes in units and their intensification, the change of the mass-transfer coefficient is analyzed with the assumption of a number of parameters. The results of the study of the effect of various structural parameters of a stream-bubble contact device on the mass-transfer coefficient in the liquid phase are given. It is proven that the mass-transfer coefficient increases in the liquid phase, in the first place, with the growth of the level of liquid in the contact element, because the rate of the liquid run-off grows in this case and, consequently, the time of surface renewal is reduced; in the second place, with an increase in the slot diameter in the downpipe, because the jet diameter and, accordingly, their section perimeter and the area of the surface that is immersed in liquid increase; and, in the third place, with an increase in the number of slots in the downpipe, because the area of the surface that is immersed in the liquid of the contact element increases. Thus, in order to increase the mass-transfer coefficient in the liquid phase, it is necessary to design the contact elements with a minimum width and a large number of slots and their increased diameter; in this case, the filling degree of contact elements by the liquid must be maximum.

X-ray and gamma-ray computed tomography for industrial nondestructive testing and evaluation

NASA Astrophysics Data System (ADS)

Costello, Ian; Wells, Peter; Davis, John R.; Benci, Nino; Skerrett, David; Davies, D. R.

1994-03-01

This paper presents an overview of two recently constructed computed tomography (CT) scanners that have been designed to provide structural information for industrially relevant materials and components. CT enables cross-sectional slices of an object to be nondestructively imaged and represented as a map of linear attenuation coefficient. As linear attenuation is the product of mass attenuation and density, this usually enables a straightforward interpretation of the image in terms of density. The two instruments are a transportable scanner using a 160 kV(peak) powered x-ray tube for the inspection of wooden power poles up to 450 mm in diameter, and an industrial scanning system designed around an Ir-192 gamma-ray source for materials characterization and the testing and evaluation of castings, ceramics, and composites. The images presented in this paper have generally been reconstructed using the summation convolution back-projection (SCBP) method, and this technique is outlined. Direct Fourier reconstruction is also used and compared with the SCBP method. A brief discussion is offered on incorporating edge detection methods into the image reconstruction process for the improved identification of defects such as cracks and voids.

Chemical Characterization and Determination of the Anti-Oxidant Capacity of Two Brown Algae with Respect to Sampling Season and Morphological Structures Using Infrared Spectroscopy and Multivariate Analyses.

PubMed

Beratto, Angelo; Agurto, Cristian; Freer, Juanita; Peña-Farfal, Carlos; Troncoso, Nicolás; Agurto, Andrés; Castillo, Rosario Del P

2017-10-01

Brown algae biomass has been shown to be a highly important industrial source for the production of alginates and different nutraceutical products. The characterization of this biomass is necessary in order to allocate its use to specific applications according to the chemical and biological characteristics of this highly variable resource. The methods commonly used for algae characterization require a long time for the analysis and rigorous pretreatments of samples. In this work, nondestructive and fast analyses of different morphological structures from Lessonia spicata and Macrocystis pyrifera, which were collected during different seasons, were performed using Fourier transform infrared (FT-IR) techniques in combination with chemometric methods. Mid-infrared (IR) and near-infrared (NIR) spectral ranges were tested to evaluate the spectral differences between the species, seasons, and morphological structures of algae using a principal component analysis (PCA). Quantitative analyses of the polyphenol and alginate contents and the anti-oxidant capacity of the samples were performed using partial least squares (PLS) with both spectral ranges in order to build a predictive model for the rapid quantification of these parameters with industrial purposes. The PCA mainly showed differences in the samples based on seasonal sampling, where changes were observed in the bands corresponding to polysaccharides, proteins, and lipids. The obtained PLS models had high correlation coefficients (r) for the polyphenol content and anti-oxidant capacity (r > 0.9) and lower values for the alginate determination (0.7 < r < 0.8). Fourier transform infrared-based techniques were suitable tools for the rapid characterization of algae biomass, in which high variability in the samples was incorporated for the qualitative and quantitative analyses, and have the potential to be used on an industrial scale.

Measurements of complex impedance in microwave high power systems with a new bluetooth integrated circuit.

PubMed

Roussy, Georges; Dichtel, Bernard; Chaabane, Haykel

2003-01-01

By using a new integrated circuit, which is marketed for bluetooth applications, it is possible to simplify the method of measuring the complex impedance, complex reflection coefficient and complex transmission coefficient in an industrial microwave setup. The Analog Devices circuit AD 8302, which measures gain and phase up to 2.7 GHz, operates with variable level input signals and is less sensitive to both amplitude and frequency fluctuations of the industrial magnetrons than are mixers and AM crystal detectors. Therefore, accurate gain and phase measurements can be performed with low stability generators. A mechanical setup with an AD 8302 is described; the calibration procedure and its performance are presented.

Banded Structures in Electron Pitch Angle Diffusion Coefficients from Resonant Wave Particle Interactions

NASA Technical Reports Server (NTRS)

Tripathi, A. K.; Singhal, R. P.; Khazanov, G. V.; Avanov, L. A.

2016-01-01

Electron pitch angle (D (alpha)) and momentum (D(pp)) diffusion coefficients have been calculated due to resonant interactions with electrostatic electron cyclotron harmonic (ECH) and whistler mode chorus waves. Calculations have been performed at two spatial locations L = 4.6 and 6.8 for electron energies 10 keV. Landau (n = 0) resonance and cyclotron harmonic resonances n = +/-1, +/-2,...+/-5 have been included in the calculations. It is found that diffusion coefficient versus pitch angle (alpha) profiles show large dips and oscillations or banded structures. The structures are more pronounced for ECH and lower band chorus (LBC) and particularly at location 4.6. Calculations of diffusion coefficients have also been performed for individual resonances. It is noticed that the main contribution of ECH waves in pitch angle diffusion coefficient is due to resonances n = +1 and n = +2. A major contribution to momentum diffusion coefficients appears from n = +2. However, the banded structures in D alpha and Dpp coefficients appear only in the profile of diffusion coefficients for n = +2. The contribution of other resonances to diffusion coefficients is found to be, in general, quite small or even negligible. For LBC and upper band chorus waves, the banded structures appear only in Landau resonance. The Dpp diffusion coefficient for ECH waves is one to two orders smaller than D alpha coefficients. For chorus waves, Dpp coefficients are about an order of magnitude smaller than D alpha coefficients for the case n does not = 0. In case of Landau resonance, the values of Dpp coefficient are generally larger than the values of D alpha coefficients particularly at lower energies. As an aid to the interpretation of results, we have also determined the resonant frequencies. For ECH waves, resonant frequencies have been estimated for wave normal angle 89 deg and harmonic resonances n = +1, +2, and +3, whereas for whistler mode waves, the frequencies have been calculated for angle 10 deg and Landau resonance. Further, in ECH waves, the banded structures appear for electron energies (is) greater than1 keV, and for whistler mode chorus waves, structures appear for energies greater than 2 keV at L = 4.6 and above 200 eV for L = 6.8. The results obtained in the present work will be helpful in the study of diffusion curves and will have important consequences for diffuse aurora and pancake distributions.

Banded Structures in Electron Pitch Angle Diffusion Coefficients from Resonant Wave-Particle Interactions

NASA Technical Reports Server (NTRS)

Tripathi, A. K.; Singhal, R. P.; Khazanov, G. V.; Avanov, L. A.

2016-01-01

Electron pitch angle (D(sub (alpha alpha))) and momentum (D(sub pp)) diffusion coefficients have been calculated due to resonant interactions with electrostatic electron cyclotron harmonic (ECH) and whistler mode chorus waves. Calculations have been performed at two spatial locations L=4.6 and 6.8 for electron energies less than or equal to 10 keV. Landau (n=0) resonance and cyclotron harmonic resonances n= +/- 1, +/-2, ... +/-5 have been included in the calculations. It is found that diffusion coefficient versus pitch angle (alpha) profiles show large dips and oscillations or banded structures. The structures are more pronounced for ECH and lower band chorus (LBC) and particularly at location 4.6. Calculations of diffusion coefficients have also been performed for individual resonances. It is noticed that the main contribution of ECH waves in pitch angle diffusion coefficient is due to resonances n=+1 and n=+2. A major contribution to momentum diffusion coefficients appears from n=+2. However, the banded structures in D(sub alpha alpha) and D(sub pp) coefficients appear only in the profile of diffusion coefficients for n=+2. The contribution of other resonances to diffusion coefficients is found to be, in general, quite small or even negligible. For LBC and upper band chorus waves, the banded structures appear only in Landau resonance. The D(sub pp) diffusion coefficient for ECH waves is one to two orders smaller than D(sub alpha alpha) coefficients. For chorus waves, D(sub pp) coefficients are about an order of magnitude smaller than D(sub alpha alpha) coefficients for the case n does not equal 0. In case of Landau resonance, the values of D(sub pp) coefficient are generally larger than the values of D(sub alpha alpha) coefficients particularly at lower energies. As an aid to the interpretation of results, we have also determined the resonant frequencies. For ECH waves, resonant frequencies have been estimated for wave normal angle 89 deg and harmonic resonances n= +1, +2, and +3, whereas for whistler mode waves, the frequencies have been calculated for angle 10 deg and Landau resonance. Further, in ECH waves, the banded structures appear for electron energies 1 greater than or equal to keV, and for whistler mode chorus waves, structures appear for energies greater than 2 keV at L=4.6 and above 200 eV for L=6.8. The results obtained in the present work will be helpful in the study of diffusion curves and will have important consequences for diffuse aurora and pancake distributions.

Determination of 210Pb concentration in NORM waste - An application of the transmission method for self-attenuation corrections for gamma-ray spectrometry

NASA Astrophysics Data System (ADS)

Bonczyk, Michal

2018-07-01

This article deals with the problem of the self-attenuation of low-energy gamma-rays from the isotope of lead 210Pb (46.5 keV) in industrial waste. The 167 samples of industrial waste, belonging to nine categories, were tested by means of gamma spectrometry in order to determine 210Pb activity concentration. The experimental method for self-attenuation corrections for gamma rays emitted by lead isotope was applied. Mass attenuation coefficients were determined for energy of 46.5 keV. Correction factors were calculated based on mass attenuation coefficients, sample density and thickness. A mathematical formula for correction calculation was evaluated. The 210Pb activity concentration obtained varied in the range from several Bq·kg-1 up to 19,810 Bq kg-1. The mass attenuation coefficients varied across the range of 0.19-4.42 cm2·g-1. However, the variation of mass attenuation coefficient within some categories of waste was relatively small. The calculated corrections for self-attenuation were 0.98 - 6.97. The high value of correction factors must not be neglect in radiation risk assessment.

Method of fabricating composite structures

NASA Technical Reports Server (NTRS)

Sigur, W. A. (Inventor)

1990-01-01

A method of fabricating structures formed from composite materials by positioning the structure about a high coefficient of thermal expansion material, wrapping a graphite fiber overwrap about the structure, and thereafter heating the assembly to expand the high coefficient of thermal expansion material to forcibly compress the composite structure against the restraint provided by the graphite overwrap. The high coefficient of thermal expansion material is disposed about a mandrel with a release system therebetween, and with a release system between the material having the high coefficient of thermal expansion and the composite material, and between the graphite fibers and the composite structure. The heating may occur by inducing heat into the assembly by a magnetic field created by coils disposed about the assembly through which alternating current flows. The method permits structures to be formed without the use of an autoclave.

Method of fabricating composite structures

NASA Technical Reports Server (NTRS)

Sigur, Wanda A. (Inventor)

1992-01-01

A method of fabricating structures formed from composite materials by positioning the structure about a high coefficient of thermal expansion material, wrapping a graphite fiber overwrap about the structure, and thereafter heating the assembly to expand the high coefficient of thermal expansion material to forcibly compress the composite structure against the restraint provided by the graphite overwrap. The high coefficient of thermal expansion material is disposed about a mandrel with a release system therebetween, and with a release system between the material having the high coefficient of thermal expansion and the composite material, and between the graphite fibers and the composite structure. The heating may occur by inducing heat into the assembly by a magnetic field created by coils disposed about the assembly through which alternating current flows. The method permits structures to be formed without the use of an autoclave.

Characteristic analysis of surface waves in a sensitive plasma absorption probe

NASA Astrophysics Data System (ADS)

You, Wei; Li, Hong; Tan, Mingsheng; Liu, Wandong

2018-01-01

With features that are simple to construct and a symmetric configuration, the sensitive plasma absorption probe (SPAP) is a dependable probe for industry plasma diagnosis. The minimum peak in the characteristic curve of the coefficient of reflection stems from the surface wave resonance in plasma. We use numerical simulation methods to analyse the details of the excitation and propagation of these surface waves. With this method, the electromagnetic field structure and the resonance and propagation characteristics of the surface wave were analyzed simultaneously using the simulation method. For this SPAP structure, there are three different propagation paths for the propagating plasma surface wave. The propagation characteristic of the surface wave along each path is presented. Its dispersion relation is also calculated. The objective is to complete the relevant theory of the SPAP as well as the propagation process of the plasma surface wave.

A new type of smart basalt fiber-reinforced polymer bars as both reinforcements and sensors for civil engineering application

NASA Astrophysics Data System (ADS)

Tang, Yongsheng; Wu, Zhishen; Yang, Caiqian; Wu, Gang; Shen, Sheng

2010-11-01

In this paper, a new type of smart basalt fiber-reinforced polymer (BFRP) bar is developed and their sensing performance is investigated by using the Brillouin scattering-based distributed fiber optic sensing technique. The industrial manufacturing process is first addressed, followed by an experimental study on the strain, temperature and fundamental mechanical properties of the BFRP bars. The results confirm the superior sensing properties, in particular the measuring accuracy, repeatability and linearity through comparing with bare optical fibers. Results on the mechanical properties show stable elastic modulus and high ultimate strength. Therefore, the smart BFRP bar has potential applications for long-term structural health monitoring (SHM) as embedded sensors as well as strengthening and upgrading structures. Moreover the coefficient of thermal expansion for smart BFRP bars is similar to the value for concrete.

Giant piezoelectricity of monolayer group IV monochalcogenides

NASA Astrophysics Data System (ADS)

Fei, Ruixiang; Li, Wenbin; Li, Ju; Yang, Li

We predict enormous, anisotropic piezoelectric effects in intrinsic monolayer group IV monochalcogenides (MX, M =Sn or Ge, X =Se or S), including SnSe, SnS, GeSe, and GeS. Using first-principle simulations based on the modern theory of polarization, we find that their piezoelectric coefficients are about one to two orders of magnitude larger than those of other 2D materials, such as MoS2 and GaSe, and bulk quartz and AlN which are widely used in industry. This enhancement is a result of the unique ``puckered'' C2v symmetry and electronic structure of monolayer group IV monochalcogenides. Given the achieved experimental advances in the fabrication of monolayers, their flexible character, and ability to withstand enormous strain, these 2D structures with giant piezoelectric effects may be promising for a broad range of applications such as nano-sized sensors, piezotronics, and energy harvesting in portable electronic devices.

Molecular Dynamics Simulations of Grain Boundary and Bulk Diffusion in Metals.

NASA Astrophysics Data System (ADS)

Plimpton, Steven James

Diffusion is a microscopic mass transport mechanism that underlies many important macroscopic phenomena affecting the structural, electrical, and mechanical properties of metals. This thesis presents results from atomistic simulation studies of diffusion both in bulk and in the fast diffusion paths known as grain boundaries. Using the principles of molecular dynamics single boundaries are studied and their structure and dynamic properties characterized. In particular, tilt boundary bicrystal and bulk models of fcc Al and bcc alpha-Fe are simulated. Diffusion coefficients and activation energies for atomic motion are calculated for both models and compared to experimental data. The influence of the interatomic pair potential on the diffusion is studied in detail. A universal relation between the melting temperature that a pair potential induces in a simulated bulk model and the potential energy barrier height for atomic hopping is derived and used to correlate results for a wide variety of pair potentials. Using these techniques grain boundary and bulk diffusion coefficients for any fcc material can be estimated from simple static calculations without the need to perform more time-consuming dynamic simulations. The influences of two other factors on grain boundary diffusion are also studied because of the interest of the microelectronics industry in the diffusion related reliability problem known as electromigration. The first factor, known to affect the self diffusion rate of Al, is the presence of Cu impurity atoms in Al tilt boundaries. The bicrystal model for Al is seeded randomly with Cu atoms and a simple hybrid Morse potential used to model the Al-Cu interaction. While some effect due to the Cu is noted, it is concluded that pair potentials are likely an inadequate approximation for the alloy system. The second factor studied is the effect of the boundary orientation angle on the diffusion rate. Symmetric bcc Fe boundaries are relaxed to find optimal structures and their diffusion coefficients calculated. Good agreement is found with the dislocation pipe model for tilt boundary diffusion.

Prediction of distribution coefficient from structure. 1. Estimation method.

PubMed

Csizmadia, F; Tsantili-Kakoulidou, A; Panderi, I; Darvas, F

1997-07-01

A method has been developed for the estimation of the distribution coefficient (D), which considers the microspecies of a compound. D is calculated from the microscopic dissociation constants (microconstants), the partition coefficients of the microspecies, and the counterion concentration. A general equation for the calculation of D at a given pH is presented. The microconstants are calculated from the structure using Hammett and Taft equations. The partition coefficients of the ionic microspecies are predicted by empirical equations using the dissociation constants and the partition coefficient of the uncharged species, which are estimated from the structure by a Linear Free Energy Relationship method. The algorithm is implemented in a program module called PrologD.

Acoustical and thermo physical properties of metal-ceramics composites in dependence on few volume concentration of metal

NASA Astrophysics Data System (ADS)

Abramovich, A.

2016-04-01

Metal-ceramics composites (cermets) are modern construction material used in different industry branches. Their strength and heat resistance depend on elastic and thermos physical properties. In this work cermets based on corundum and stainless steel (sintered in high vacuum at temperatures 1500 - 1600°C) are investigated. The volume steel concentration in the samples varies up 2 to 20 vol %. The elastic modules were measured by ultrasonic method at room temperature, measuring of thermo conductivity coefficient were carried out at temperatures 100, 200°C by method of continued heating in adiabatic calorimeter. We founded appearance of two extremes on dependences of elastic modules (E, G) on stainless steel concentrations, nature of which is unknown, modules values change in range: E = 110 - 310, G = 60 - 130GPa (for different temperatures of sintering). Similar dependence is observed for thermo conductivity coefficient which values varies up 10 to 40 W/(m.K). There is presented also discussion of results based on structure cermet model as multiphase micro heterogeneous media with isotropic physical properties in the work.

Structure and Mechanical Properties of CrTiAlN/TiAlN Composite Coatings Deposited by Multi-Arc Ion Plating

NASA Astrophysics Data System (ADS)

Yan, Shaojian; Tian, Canxin; Huang, Zhihong; Yang, Bing; Fu, Dejun

2014-10-01

CrTiAlN/TiAlN composite coatings were deposited on cemented carbide by using a home-made industrial scale multi-arc ion plating system. The samples were studied by X-ray diffraction, scanning electron microscopy (SEM), microhardness and ball-on-disk testing. The properties of the CrTiAlN/TiAlN coatings were significantly influenced by the microstructure and the deposition time ratio of TiAlN over CrTiAlN layers. With the increase of deposition time ratio, the microhardness of CrTiAlN/TiAlN increased from 28.6 GPa to 37.5 GPa, much higher than that of CrTiAlN coatings. The friction coefficients of the CrTiAlN/TiAlN coatings were higher than those of CrTiAlN coatings against a cemented carbide ball. The microhardness of the CrTiAlN/TiAlN coatings was changed after annealing at 800°C, and the friction coefficients of the annealed coatings were increased against the cemented carbide ball.

Pore size distribution effect on rarefied gas transport in porous media

NASA Astrophysics Data System (ADS)

Hori, Takuma; Yoshimoto, Yuta; Takagi, Shu; Kinefuchi, Ikuya

2017-11-01

Gas transport phenomena in porous media are known to strongly influence the performance of devices such as gas separation membranes and fuel cells. Knudsen diffusion is a dominant flow regime in these devices since they have nanoscale pores. Many experiments have shown that these porous media have complex structures and pore size distributions; thus, the diffusion coefficient in these media cannot be easily assessed. Previous studies have reported that the characteristic pore diameter of porous media can be defined in light of the pore size distribution; however, tortuosity factor, which is necessary for the evaluation of diffusion coefficient, is still unknown without gas transport measurements or simulations. Thus, the relation between pore size distributions and tortuosity factors is required to obtain the gas transport properties. We perform numerical simulations to prove the relation between them. Porous media are numerically constructed while satisfying given pore size distributions. Then, the mean-square displacement simulation is performed to obtain the tortuosity factors of the constructed porous media.. This paper is based on results obtained from a project commissioned by the New Energy and Industrial Development Organization (NEDO).

How Do Social Networks Influence Learning Outcomes? A Case Study in an Industrial Setting

ERIC Educational Resources Information Center

Maglajlic, Seid; Helic, Denis

2012-01-01

and Purpose: The purpose of this research is to shed light on the impact of implicit social networks to the learning outcome of e-learning participants in an industrial setting. Design/methodology/approach: The paper presents a theoretical framework that allows the authors to measure correlation coefficients between the different affiliations that…

Compressed-Sensing Reconstruction Based on Block Sparse Bayesian Learning in Bearing-Condition Monitoring

PubMed Central

Sun, Jiedi; Yu, Yang; Wen, Jiangtao

2017-01-01

Remote monitoring of bearing conditions, using wireless sensor network (WSN), is a developing trend in the industrial field. In complicated industrial environments, WSN face three main constraints: low energy, less memory, and low operational capability. Conventional data-compression methods, which concentrate on data compression only, cannot overcome these limitations. Aiming at these problems, this paper proposed a compressed data acquisition and reconstruction scheme based on Compressed Sensing (CS) which is a novel signal-processing technique and applied it for bearing conditions monitoring via WSN. The compressed data acquisition is realized by projection transformation and can greatly reduce the data volume, which needs the nodes to process and transmit. The reconstruction of original signals is achieved in the host computer by complicated algorithms. The bearing vibration signals not only exhibit the sparsity property, but also have specific structures. This paper introduced the block sparse Bayesian learning (BSBL) algorithm which works by utilizing the block property and inherent structures of signals to reconstruct CS sparsity coefficients of transform domains and further recover the original signals. By using the BSBL, CS reconstruction can be improved remarkably. Experiments and analyses showed that BSBL method has good performance and is suitable for practical bearing-condition monitoring. PMID:28635623

The Sensitivity of Large-Eddy Simulation to Local and Nonlocal Drag Coefficients at the Lower Boundary

NASA Technical Reports Server (NTRS)

Schowalter, D. G.; DeCroix, D. S.; Lin, Y. L.; Arya, S. P.; Kaplan, M. L.

1996-01-01

It was found that the homogeneity of the surface drag coefficient plays an important role in the large scale structure of turbulence in large-eddy simulation of the convective atmospheric boundary layer. Particularly when a ground surface temperature was specified, large horizontal anisotropies occurred when the drag coefficient depended upon local velocities and heat fluxes. This was due to the formation of streamwise roll structures in the boundary layer. In reality, these structures have been found to form when shear is approximately balanced by buoyancy. The present cases, however, were highly convective. The formation was caused by particularly low values of the drag coefficient at the entrance to thermal plume structures.

Time Domain Diffraction by Composite Structures

NASA Astrophysics Data System (ADS)

Riccio, Giovanni; Frongillo, Marcello

2017-04-01

Time domain (TD) diffraction problems are receiving great attention because of the widespread use of ultra wide band (UWB) communication and radar systems. It is commonly accepted that, due to the large bandwidth of the UWB signals, the analysis of the wave propagation mechanisms in the TD framework is preferable to the frequency domain (FD) data processing. Furthermore, the analysis of transient scattering phenomena is also of importance for predicting the effects of electromagnetic pulses on civil structures. Diffraction in the TD framework represents a challenging problem and numerical discretization techniques can be used to support research and industry activities. Unfortunately, these methods become rapidly intractable when considering excitation pulses with high frequency content. This contribution deals with the TD diffraction phenomenon related to composite structures containing a dielectric wedge with arbitrary apex angle when illuminated by a plane wave. The approach is the same used in [1]-[3]. The transient diffracted field originated by an arbitrary function plane wave is evaluated via a convolution integral involving the TD diffraction coefficients, which are determined in closed form starting from the knowledge of the corresponding FD counterparts. In particular, the inverse Laplace transform is applied to the FD Uniform Asymptotic Physical Optics (FD-UAPO) diffraction coefficients available for the internal region of the structure and the surrounding space. For each observation domain, the FD-UAPO expressions are obtained by considering electric and magnetic equivalent PO surface currents located on the interfaces. The surface radiation integrals using these sources is assumed as starting point and manipulated for obtaining integrals able to be solved by means of the Steepest Descent Method and the Multiplicative Method. [1] G. Gennarelli and G. Riccio, "Time domain diffraction by a right-angled penetrable wedge," IEEE Trans. Antennas Propag., Vol. 60, 2829-2833, 2012. [2] G. Gennarelli and G. Riccio, "Obtuse-angled penetrable wedges: a time domain solution for the diffraction coefficients," J. Electromagn. Waves Appl., Vol. 27, 2020-2028, 2013. [3] M. Frongillo, G. Gennarelli and G. Riccio, "TD-UAPO diffracted field evaluation for penetrable wedges with acute apex angle," J. Opt. Soc. Am. A, Vol. 32, 1271-1275, 2015.

Banded structures in electron pitch angle diffusion coefficients from resonant wave-particle interactions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tripathi, A. K., E-mail: aktrip2001@yahoo.co.in; Singhal, R. P., E-mail: rpsiitbhu@yahoo.com; Khazanov, G. V., E-mail: George.V.Khazanov@nasa.gov

2016-04-15

Electron pitch angle (D{sub αα}) and momentum (D{sub pp}) diffusion coefficients have been calculated due to resonant interactions with electrostatic electron cyclotron harmonic (ECH) and whistler mode chorus waves. Calculations have been performed at two spatial locations L = 4.6 and 6.8 for electron energies ≤10 keV. Landau (n = 0) resonance and cyclotron harmonic resonances n = ±1, ±2, … ±5 have been included in the calculations. It is found that diffusion coefficient versus pitch angle (α) profiles show large dips and oscillations or banded structures. The structures are more pronounced for ECH and lower band chorus (LBC) and particularly at location 4.6. Calculations of diffusionmore » coefficients have also been performed for individual resonances. It is noticed that the main contribution of ECH waves in pitch angle diffusion coefficient is due to resonances n = +1 and n = +2. A major contribution to momentum diffusion coefficients appears from n = +2. However, the banded structures in D{sub αα} and D{sub pp} coefficients appear only in the profile of diffusion coefficients for n = +2. The contribution of other resonances to diffusion coefficients is found to be, in general, quite small or even negligible. For LBC and upper band chorus waves, the banded structures appear only in Landau resonance. The D{sub pp} diffusion coefficient for ECH waves is one to two orders smaller than D{sub αα} coefficients. For chorus waves, D{sub pp} coefficients are about an order of magnitude smaller than D{sub αα} coefficients for the case n ≠ 0. In case of Landau resonance, the values of D{sub pp} coefficient are generally larger than the values of D{sub αα} coefficients particularly at lower energies. As an aid to the interpretation of results, we have also determined the resonant frequencies. For ECH waves, resonant frequencies have been estimated for wave normal angle 89° and harmonic resonances n = +1, +2, and +3, whereas for whistler mode waves, the frequencies have been calculated for angle 10° and Landau resonance. Further, in ECH waves, the banded structures appear for electron energies ≥1 keV, and for whistler mode chorus waves, structures appear for energies >2 keV at L = 4.6 and above 200 eV for L = 6.8. The results obtained in the present work will be helpful in the study of diffusion curves and will have important consequences for diffuse aurora and pancake distributions.« less

Virtual Water Transfers in U.S. Cities from Domestic Commodity Flows

NASA Astrophysics Data System (ADS)

Ahams, I. C.; Mejia, A.; Paterson, W.

2015-12-01

Cities have imported water into their boundaries for centuries but understanding how cities indirectly affect watersheds through the commodities which they import is fairly unknown. Thus, we present and discuss here a methodology for determining the virtual water transfers to and from U.S. cities associated with domestic commodity flows. For our methodology, we only consider agricultural and industrial commodities and, to represent the commodity flows, we use the Freight Analysis Framework (FAF) dataset from the U.S. Department of Transportation. Accordingly, we determine virtual water transfers for the 123 geographic regions in the FAF, which consists of 17 states, 73 metropolitan statistical areas (MSAs), and 33 remainders of states. Out of the 41 sectors that comprise the FAF data, we consider only the 29 sectors that account for the agricultural and industrial commodities. Using both water use data for macro-sectors and national water use coefficients for different industries, we determine a weighted water use coefficient for each of the 29 sectors considered. Ultimately, we use these weighted coefficients to estimate virtual water transfers and the water footprint for each city. Preliminary comparisons with other water footprint estimates indicate that our methodology yields reasonable results. In terms of the water footprint, we find that cities (i.e. MSAs) are net consumers, can consume a large proportion of their own production, and can have a large agricultural production. We also find that the per capita water footprint of industrial consumption decreases with increasing population in cities, suggesting that large cities may be more efficient.

Scaling features of the tribology of polymer brushes of increasing grafting density around the mushroom-to-brush transition.

PubMed

Mayoral, E; Klapp, J; Gama Goicochea, A

2017-01-01

Nonequilibrium coarse-grained, dissipative particle dynamics simulations of complex fluids, made up of polymer brushes tethered to planar surfaces immersed in a solvent yield nonmonotonic behavior of the friction coefficient as a function of the polymer grating density on the substrates, Γ, while the viscosity shows a monotonically increasing dependence on Γ. This effect is shown to be independent of the degree of polymerization, N, and the size of the system. It arises from the composition and the structure of the first particle layer adjacent to each surface that results from the confinement of the fluid. Whenever such layers are made up of as close a proportion of polymer beads to solvent particles as there are in the fluid, the friction coefficient shows a minimum, while for disparate proportions the friction coefficient grows. At the mushroom-to-brush transition (MBT) the viscosity scales with an exponent that depends on the characteristic exponent of the MBT (6/5) and the solvent quality exponent (ν=0.5, for θsolvent), but it is independent of the polymerization degree (N). On the other hand, the friction coefficient at the MBT scales as μ∼N^{6/5}, while the grafting density at the MBT scales as Γ∼N^{-6/5} when friction is minimal, in agreement with previous scaling theories. We argue these aspects are the result of cooperative phenomena that have important implications for the understanding of biological brushes and the design of microfluidics devices, among other applications of current academic and industrial interest.

Comparing the structure of an emerging market with a mature one under global perturbation

NASA Astrophysics Data System (ADS)

Namaki, A.; Jafari, G. R.; Raei, R.

2011-09-01

In this paper we investigate the Tehran stock exchange (TSE) and Dow Jones Industrial Average (DJIA) in terms of perturbed correlation matrices. To perturb a stock market, there are two methods, namely local and global perturbation. In the local method, we replace a correlation coefficient of the cross-correlation matrix with one calculated from two Gaussian-distributed time series, whereas in the global method, we reconstruct the correlation matrix after replacing the original return series with Gaussian-distributed time series. The local perturbation is just a technical study. We analyze these markets through two statistical approaches, random matrix theory (RMT) and the correlation coefficient distribution. By using RMT, we find that the largest eigenvalue is an influence that is common to all stocks and this eigenvalue has a peak during financial shocks. We find there are a few correlated stocks that make the essential robustness of the stock market but we see that by replacing these return time series with Gaussian-distributed time series, the mean values of correlation coefficients, the largest eigenvalues of the stock markets and the fraction of eigenvalues that deviate from the RMT prediction fall sharply in both markets. By comparing these two markets, we can see that the DJIA is more sensitive to global perturbations. These findings are crucial for risk management and portfolio selection.

Dynamics of gas-thrust bearings

NASA Technical Reports Server (NTRS)

Stiffler, A. K.; Tapia, R. R.

1978-01-01

Computer program calculates load coefficients, up to third harmonic, for hydrostatic gas thrust bearings. Program is useful in identification of industrial situations where gas-thrust bearings have potential applications.

Acoustic echo cancellation for full-duplex voice transmission on fading channels

NASA Technical Reports Server (NTRS)

Park, Sangil; Messer, Dion D.

1990-01-01

This paper discusses the implementation of an adaptive acoustic echo canceler for a hands-free cellular phone operating on a fading channel. The adaptive lattice structure, which is particularly known for faster convergence relative to the conventional tapped-delay-line (TDL) structure, is used in the initialization stage. After convergence, the lattice coefficients are converted into the coefficients for the TDL structure which can accommodate a larger number of taps in real-time operation due to its computational simplicity. The conversion method of the TDL coefficients from the lattice coefficients is derived and the DSP56001 assembly code for the lattice and TDL structure is included, as well as simulation results and the schematic diagram for the hardware implementation.

Effect of particle-size dynamics on properties of dense spongy-particle systems: Approach towards equilibrium.

PubMed

Zakhari, Monica E A; Anderson, Patrick D; Hütter, Markus

2017-07-01

Open-porous deformable particles, often envisaged as sponges, are ubiquitous in biological and industrial systems (e.g., casein micelles in dairy products and microgels in cosmetics). The rich behavior of these suspensions is owing to the elasticity of the supporting network of the particle, and the viscosity of permeating solvent. Therefore, the rate-dependent size change of these particles depends on their structure, i.e., the permeability. This work aims at investigating the effect of the particle-size dynamics and the underlying particle structure, i.e., the particle permeability, on the transient and long-time behavior of suspensions of spongy particles in the absence of applied deformation, using the dynamic two-scale model developed by Hütter et al. [Farad. Discuss. 158, 407 (2012)1359-664010.1039/c2fd20025b]. In the high-density limit, the transient behavior is found to be accelerated by the particle-size dynamics, even at average size changes as small as 1%. The accelerated dynamics is evidenced by (i) the higher short-time diffusion coefficient as compared to elastic-particle systems and (ii) the accelerated formation of the stable fcc crystal structure. Furthermore, after long times, the particle-size dynamics of spongy particles is shown to result in lower stationary values of the energy and normal stresses as compared to elastic-particle systems. This dependence of the long-time behavior of these systems on the permeability, that essentially is a transport coefficient and hence must not affect the equilibrium properties, confirms that full equilibration has not been reached.

Effect of particle-size dynamics on properties of dense spongy-particle systems: Approach towards equilibrium

NASA Astrophysics Data System (ADS)

Zakhari, Monica E. A.; Anderson, Patrick D.; Hütter, Markus

2017-07-01

Open-porous deformable particles, often envisaged as sponges, are ubiquitous in biological and industrial systems (e.g., casein micelles in dairy products and microgels in cosmetics). The rich behavior of these suspensions is owing to the elasticity of the supporting network of the particle, and the viscosity of permeating solvent. Therefore, the rate-dependent size change of these particles depends on their structure, i.e., the permeability. This work aims at investigating the effect of the particle-size dynamics and the underlying particle structure, i.e., the particle permeability, on the transient and long-time behavior of suspensions of spongy particles in the absence of applied deformation, using the dynamic two-scale model developed by Hütter et al. [Farad. Discuss. 158, 407 (2012), 10.1039/c2fd20025b]. In the high-density limit, the transient behavior is found to be accelerated by the particle-size dynamics, even at average size changes as small as 1 % . The accelerated dynamics is evidenced by (i) the higher short-time diffusion coefficient as compared to elastic-particle systems and (ii) the accelerated formation of the stable fcc crystal structure. Furthermore, after long times, the particle-size dynamics of spongy particles is shown to result in lower stationary values of the energy and normal stresses as compared to elastic-particle systems. This dependence of the long-time behavior of these systems on the permeability, that essentially is a transport coefficient and hence must not affect the equilibrium properties, confirms that full equilibration has not been reached.

Factor Scores, Structure and Communality Coefficients: A Primer

ERIC Educational Resources Information Center

Odum, Mary

2011-01-01

(Purpose) The purpose of this paper is to present an easy-to-understand primer on three important concepts of factor analysis: Factor scores, structure coefficients, and communality coefficients. Given that statistical analyses are a part of a global general linear model (GLM), and utilize weights as an integral part of analyses (Thompson, 2006;…

Estimating time-varying conditional correlations between stock and foreign exchange markets

NASA Astrophysics Data System (ADS)

Tastan, Hüseyin

2006-02-01

This study explores the dynamic interaction between stock market returns and changes in nominal exchange rates. Many financial variables are known to exhibit fat tails and autoregressive variance structure. It is well-known that unconditional covariance and correlation coefficients also vary significantly over time and multivariate generalized autoregressive model (MGARCH) is able to capture the time-varying variance-covariance matrix for stock market returns and changes in exchange rates. The model is applied to daily Euro-Dollar exchange rates and two stock market indexes from the US economy: Dow-Jones Industrial Average Index and S&P500 Index. The news impact surfaces are also drawn based on the model estimates to see the effects of idiosyncratic shocks in respective markets.

Piezoelectric and dielectric properties of nanoporous polyvinylidence fluoride (PVDF) films

NASA Astrophysics Data System (ADS)

Zhao, Ping; Wang, Shifa; Kadlec, Alec

2016-04-01

A nanoporous polyvinylidene Fluoride (PVDF) thin film was developed for applications in energy harvesting, medical surgeries, and industrial robotics. This sponge-like nanoporous PVDF structure dramatically enhanced the piezoelectric effect because it yielded considerably large deformation under a small force. A casting-etching method was adopted to make films, which is effective to control the porosity, flexibility, and thickness of the film. The films with various Zinc Oxide (ZnO) mass fractions ranging from 10 to 50% were fabricated to investigate the porosity effect. The piezoelectric coefficient d33 as well as dielectric constant and loss of the films were characterized. The results were analyzed and the optimal design of the film with the right amount of ZnO nanoparticles was determined.

Development of a highly sensitive and specific monoclonal antibody based enzyme-linked immunosorbent assay for the detection of a new β-agonist, phenylethanolamine A, in food samples.

PubMed

Jiang, Danni; Cao, Biyun; Wang, Meiyu; Yang, Hong; Zhao, Kang; Li, Jianguo; Li, Mingxin; Sun, Lulu; Deng, Anping

2017-02-01

All β-agonists are banned as feed additives for growth promotion in animals due to toxic effects on humans after consuming the β-agonist contaminated meats. Phenylethanolamine A (PA) is a newly emerged β-agonist. Thus there is a need to develop highly sensitive and specific analytical methods for the detection of PA in food samples. In this study, the monoclonal antibody (mAb) against PA was produced by hybridoma technology and used for the development of enzyme-linked immunosorbent assay (ELISA). The IC 50 values and limits of detection (LODs) of the ELISA using homogeneous combination of coating antigen/antibody for PA were 0.16 ng mL -1 and 0.011 ng mL -1 , respectively. The cross-reactive (CR) values of the assay with 14 structurally related β-agonists were lower than 0.59%. Swine liver and meat samples were spiked with PA at different content and analysed by ELISA. Acceptable recovery rates of 91.40-105.51% and intra-assay coefficients of variation of 1.56-9.92% (n = 3) were obtained. The ELISA for seven spiked samples was confirmed by LC-MS/MS with a high correlation coefficient of 0.9881. The proposed mAb-based ELISA was highly sensitive and specific for PA and could be used as a quantitative/screening method for PA analysis in food samples. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

Network community structure and loop coefficient method

NASA Astrophysics Data System (ADS)

Vragović, I.; Louis, E.

2006-07-01

A modular structure, in which groups of tightly connected nodes could be resolved as separate entities, is a property that can be found in many complex networks. In this paper, we propose a algorithm for identifying communities in networks. It is based on a local measure, so-called loop coefficient that is a generalization of the clustering coefficient. Nodes with a large loop coefficient tend to be core inner community nodes, while other vertices are usually peripheral sites at the borders of communities. Our method gives satisfactory results for both artificial and real-world graphs, if they have a relatively pronounced modular structure. This type of algorithm could open a way of interpreting the role of nodes in communities in terms of the local loop coefficient, and could be used as a complement to other methods.

Contribution of heat transfer to turbine blades and vanes for high temperature industrial gas turbines. Part 2: Heat transfer on serpentine flow passage.

PubMed

Takeishi, K; Aoki, S

2001-05-01

The improvement of the heat transfer coefficient of the 1st row blades in high temperature industrial gas turbines is one of the most important issues to ensure reliable performance of these components and to attain high thermal efficiency of the facility. This paper deals with the contribution of heat transfer to increase the turbine inlet temperature of such gas turbines in order to attain efficient and environmentally benign engines. Following the experiments described in Part 1, a set of trials was conducted to clarify the influence of the blade's rotating motion on the heat transfer coefficient for internal serpentine flow passages with turbulence promoters. Test results are shown and discussed in this second part of the contribution.

Precancerous esophageal epithelia are associated with significantly increased scattering coefficients

PubMed Central

Su, Jing-Wei; Lin, Yang-Hsien; Chiang, Chun-Ping; Lee, Jang-Ming; Hsieh, Chao-Mao; Hsieh, Min-Shu; Yang, Pei-Wen; Wang, Chen-Ping; Tseng, Ping-Huei; Lee, Yi-Chia; Sung, Kung-Bin

2015-01-01

The progression of epithelial precancers into cancer is accompanied by changes of tissue and cellular structures in the epithelium. Correlations between the structural changes and scattering coefficients of esophageal epithelia were investigated using quantitative phase images and the scattering-phase theorem. An ex vivo study of 14 patients demonstrated that the average scattering coefficient of precancerous epithelia was 37.8% higher than that of normal epithelia from the same patient. The scattering coefficients were highly correlated with morphological features including the cell density and the nuclear-to-cytoplasmic ratio. A high interpatient variability in scattering coefficients was observed and suggests identifying precancerous lesions based on the relative change in scattering coefficients. PMID:26504630

The relationship between bond ionicity, lattice energy, coefficient of thermal expansion and microwave dielectric properties of Nd(Nb(1-x)Sb(x))O4 ceramics.

PubMed

Zhang, Ping; Zhao, Yonggui; Wang, Xiuyu

2015-06-28

The crystalline structure refinement, chemical bond ionicity, lattice energy and coefficient of thermal expansion were carried out for Nd(Nb(1-x)Sb(x))O4 ceramics with a monoclinic fergusonite structure to investigate the correlations between the crystalline structure, phase stability, bond ionicity, lattice energy, coefficient of thermal expansion, and microwave dielectric properties. The bond ionicity, lattice energy, and coefficient of thermal expansion of Nd(Nb(1-x)Sb(x))O4 ceramics were calculated using a semiempirical method based on the complex bond theory. The phase structure stability varied with the lattice energy which was resulted by the substitution constant of Sb(5+). With the increasing of the Sb(5+) contents, the decrease of Nb/Sb-O bond ionicity was observed, which could be contributed to the electric polarization. The ε(r) had a close relationship with the Nb/Sb-O bond ionicity. The increase of the Q×f and |τ(f)| values could be attributed to the lattice energy and the coefficient of thermal expansion. The microwave dielectric properties of Nd(Nb(1-x)Sb(x))O4 ceramics with the monoclinic fergusonite structure were strongly dependent on the chemical bond ionicity, lattice energy and coefficient of thermal expansion.

Dataset on Investigating the role of onsite learning in the optimisation of craft gang's productivity in the construction industry.

PubMed

Ugulu, Rex Asibuodu; Allen, Stephen

2017-12-01

The data presented in this article is an original data on "Investigating the role of onsite learning in the optimisation of craft gang's productivity in the construction industry". This article describes the constraints influencing craft gang's productivity and the influence of onsite learning on the blockwork craft gang's productivity. It also presented the method of data collection, using a semi-structured interview and an observation method to collect data from construction organisations. We provided statistics on the top most important constraints affecting the craft gang's productivity using 3-D Bar charts. In addition, we computed the correlation coefficients and the regression model on the influence of onsite learning on craft gang's productivity using the man-hour as the dependent variable. The relationship between blockwork inputs and cycle numbers was determined at 5% significance level. Finally, we presented data information on the application of the learning curve theory using the unit straight-line model equations and computed the learning rate of the observed craft gang's blockwork repetitive work.

Experimental research on friction coefficient between grain bulk and bamboo clappers

NASA Astrophysics Data System (ADS)

Tang, Gan; Sun, Ping; Zhao, Yanqi; Yin, Lingfeng; Zhuang, Hong

2017-12-01

A silo is an important piece of storage equipment, especially in the grain industry. The internal friction angle and the friction coefficient between the grain and the silo wall are the main parameters needed for calculating the lateral pressure of the silo wall. Bamboo is used in silo walls, but there are no provisions about the friction coefficient between bulk grain and bamboo clappers in existing codes. In this paper, the material of the silo wall is bamboo. The internal friction of five types of grain and the friction coefficient between the grain and the bamboo clappers were measured with an equal-strain direct shear apparatus. By comparing the experimental result values with the code values, the friction coefficient between the grain bulk and bamboo clappers is lower than that between grain and steel wall and that between grain and concrete wall. The differences in value are 0.21 and 0.09, respectively.

Lateral mixing in the Mississippi River below the confluence with the Ohio River

USGS Publications Warehouse

Rathbun, R.E.; Rostad, C.E.

2004-01-01

Lateral dispersion coefficients for two dispersants were determined for three sections of the Mississippi River below the confluence with the Ohio River. The dispersants were the specific conductance and an industrial organic compound (trimethyltriazinetrione). Three models based on the stream tube concept were used, and lateral dispersion coefficients computed from these models were comparable. Coefficients for the two dispersants also were comparable. Lateral dispersion coefficients were consistent with expectations based on the characteristics of the river sections. Overall average values were 0.444 m2/s for a relatively straight section of river, 1.69 m2/s for a section containing two sharp bends, and 2.22 m2/s for a long section containing four sharp bends and several small islands. The lateral dispersion coefficients measured for the Mississippi River are consistent with literature data and a water discharge relation. Results of this study provide lateral dispersion coefficients for a water discharge not previously reported in the literature as well as new values for the Mississippi River.

Accelerated Electron-Beam Formation with a High Capture Coefficient in a Parallel Coupled Accelerating Structure

NASA Astrophysics Data System (ADS)

Chernousov, Yu. D.; Shebolaev, I. V.; Ikryanov, I. M.

2018-01-01

An electron beam with a high (close to 100%) coefficient of electron capture into the regime of acceleration has been obtained in a linear electron accelerator based on a parallel coupled slow-wave structure, electron gun with microwave-controlled injection current, and permanent-magnet beam-focusing system. The high capture coefficient was due to the properties of the accelerating structure, beam-focusing system, and electron-injection system. Main characteristics of the proposed systems are presented.

Variations in Withdrawal, Return Flow, and Consumptive Use of Water in Ohio and Indiana, with Selected Data from Wisconsin, 1999-2004

USGS Publications Warehouse

Shaffer, Kimberly H.

2009-01-01

This report contains an analysis of water withdrawal and return-flow data for Ohio and withdrawal data for Indiana and Wisconsin to compute consumptive-use coefficients and to describe monthly variability of withdrawals and consumptive use. Concurrent data were available for most water-use categories from 1999 through 2004. Average monthly water withdrawals are discussed for a variety of water-use categories, and average water use per month is depicted graphically for Ohio, Indiana, and Wisconsin (public supply only). For most water-use categories, the summer months were those of highest withdrawal and highest consumptive use. For public supply, average monthly withdrawals ranged from 1,380 million gallons per day (Mgal/d) (November) to 1,620 Mgal/d (July) in Ohio, 621 Mgal/d (December) to 816 Mgal/d (July) in Indiana, and 515 Mgal/d (December) to 694 Mgal/d (July) in Wisconsin. Ohio and Indiana thermoelectric facilities had large increases in average monthly withdrawals in the summer months (5,520 Mgal/d in March to 7,510 Mgal/d in August for Indiana; 7,380 Mgal/d in February to 10,040 Mgal/d in July for Ohio), possibly because of increased electricity production in the summer, a need for additional cooling-water withdrawals when intake-water temperature is high, or use of different types of cooling methods during different times of the year. Average industrial withdrawals ranged from 2,220 Mgal/d (December) to 2,620 Mgal/d (August) in Indiana and from 707 Mgal/d (January) to 787 Mgal/d (August) in Ohio. The Ohio and Indiana irrigation data showed that most withdrawals were in May through October for golf courses, nurseries, and crop irrigation. Commercial water withdrawals ranged from 30.4 Mgal/d (January) to 65.0 Mgal/d (September) in Indiana and from 23.2 Mgal/d (November) to 49.5 Mgal/d (August) in Ohio; commercial facilities that have high water demand in Ohio and Indiana are medical facilities, schools, amusement facilities, wildlife facilities, large stores, colleges, correctional institutions, and national security facilities. Monthly livestock withdrawals were constant for Ohio but were more variable in Indiana and depended on whether the livestock facility operated on a seasonal schedule. Aquaculture withdrawals appeared to correlate with growing seasons and with aeration of ponds during the winter months. Mining withdrawals - specifically, those for nonmetallic mining - tended to be highest in April and may be related to dewatering. Consumptive use and consumptive-use coefficients were computed by two principal methods in this study: the return-flow and withdrawal method (RW; Ohio only) and the winter-base-rate method (WBR; Ohio, Indiana and Wisconsin). The WBR method was not suitable for the thermoelectric, industrial, irrigation, livestock, aquaculture, and mining water-use categories. The RW method was not used for public-supply facilities. A third method, the Standard Industrial Classification code method (SIC), was used only for certain industrial facilities. The public-supply annual average consumptive-use coefficient derived by use of the WBR methods ranged from 6 to 8 percent among Ohio, Indiana, and Wisconsin; the summer average consumptive-use coefficient was considerably higher, ranging from 16 to 20 percent. The commercial annual consumptive-use coefficient for both Ohio and Indiana was 30 percent by the WBR method, which fell within the Ohio annual median (17 percent) and annual average (42 percent) by the RW method. Thermoelectric consumptive use differs greatly by the type of cooling the facility uses; the Ohio annual median consumptive-use coefficient (RW method) was 2 percent for all thermoelectric facilities and facilities with multiple types of cooling, but exclusively once-through-cooling facilities had a median of 0 percent and exclusively closed-loop-cooling facilities had a median of 25 percent. Industrial consumptive-use coefficients varied by type of industry, as reflected by SIC code

Validation of the French version of the Child Post-Traumatic Stress Reaction Index: psychometric properties in French speaking school-aged children.

PubMed

Olliac, Bertrand; Birmes, Philippe; Bui, Eric; Allenou, Charlotte; Brunet, Alain; Claudet, Isabelle; Sales de Gauzy, Jérôme; Grandjean, Hélène; Raynaud, Jean-Philippe

2014-01-01

Although the reliable and valid Child Post-Traumatic Stress Reaction Index (CPTS-RI) is a widely used measure of posttraumatic stress disorder (PTSD) symptoms in children, it has not been validated in French-speaking populations. The present study aims to assess the psychometric properties of the CPTS-RI in three samples of French-speaking school-children. Data was obtained from three samples. Sample 1 was composed of 106 children (mean (SD) age = 11.7(0.7), 50% females) victims of an industrial disaster. Sample 2 was composed of 50 children (mean (SD) age = 10.8(2.6), 44% females) who had received an orthopaedic surgical procedure after an accident. Sample 3 was composed of 106 children (mean (SD) age = 11.7(2.2), 44% females) admitted to an emergency department after a road traffic accident. We tested internal consistency using Cronbach's alpha. We examined test-retest reliability using intraclass correlation coefficient. In order to assess the convergent validity of the French version of the CPTS-RI and the Clinician Administered PTS Scale-Child and Adolescent (CAPS-CA), spearman-correlation coefficient was computed. To verify the validity of the cut-off scores, a ROC curve was constructed which evaluated the sensitivity and specificity of each score compared to the diagnosis with the CAPS-CA. We also used principal components analysis with varimax rotation to study the structure of the French version of the CPTS-RI. Cronbach's alpha coefficient was 0.87 for the French version of the CPTS-RI. Two-week test-retest intraclass correlation coefficient (n = 30) was 0.67. The French version of the CPTS-RI was well correlated with the CAPS-CA (r = 0.76, p < 0.001). Taking the CAPS-CA as the diagnostic reference, with a diagnostic cut-off of >24 for the CPTS-RI, the sensitivity and specificities were 100% and 62.6%, respectively. The French version of the CPTS-RI demonstrated a three-factor structure. The CPTS-RI is reliable and valid in French-speaking children.

Heat transfer coefficient distribution over the inconel plate cooled from high temperature by the array of water jets

NASA Astrophysics Data System (ADS)

Malinowski, Z.; Telejko, T.; Cebo-Rudnicka, A.; Szajding, A.; Rywotycki, M.; Hadała, B.

2016-09-01

The industrial rolling mills are equipped with systems for controlled water cooling of hot steel products. A cooling rate affects the final mechanical properties of steel which are strongly dependent on microstructure evolution processes. In case of water jets cooling the heat transfer boundary condition can be defined by the heat transfer coefficient. In the present study one and three dimensional heat conduction models have been employed in the inverse solution to heat transfer coefficient. The inconel plate has been heated to about 900oC and then cooled by one, two and six water jets. The plate temperature has been measured by 30 thermocouples. The heat transfer coefficient distributions at plate surface have been determined in time of cooling.

Ordering structured populations in multiplayer cooperation games

PubMed Central

Peña, Jorge; Wu, Bin; Traulsen, Arne

2016-01-01

Spatial structure greatly affects the evolution of cooperation. While in two-player games the condition for cooperation to evolve depends on a single structure coefficient, in multiplayer games the condition might depend on several structure coefficients, making it difficult to compare different population structures. We propose a solution to this issue by introducing two simple ways of ordering population structures: the containment order and the volume order. If population structure is greater than population structure in the containment or the volume order, then can be considered a stronger promoter of cooperation. We provide conditions for establishing the containment order, give general results on the volume order, and illustrate our theory by comparing different models of spatial games and associated update rules. Our results hold for a large class of population structures and can be easily applied to specific cases once the structure coefficients have been calculated or estimated. PMID:26819335

Giant magnetoelectric effect in negative magnetostrictive/piezoelectric/positive magnetostrictive semiring structure

NASA Astrophysics Data System (ADS)

Zeng, Lingyu; Zhou, Minhong; Bi, Ke; Lei, Ming

2016-01-01

Magnetoelectric (ME) Ni/PZT/TbFe2 and TbFe2/PZT composites with two semiring structures are prepared. The dependence between ME coupling and magnetostrictive property of the composite is discussed. Because Ni possesses negative magnetostrictive property and TbFe2 shows positive magnetostrictive property, the ME voltage coefficient of Ni/PZT/TbFe2 semiring structure is much larger than that of TbFe2/PZT. In these composites, the ME voltage coefficient increases and the resonance frequency gradually decreases with the increase of the semiring radius, showing that structural parameters are key factors to the composite properties. Due to the strong ME coupling effect, a giant ME voltage coefficient αE = 44.8 V cm-1 Oe-1 is obtained. This approach opens a way for the design of ME composites with giant ME voltage coefficient.

Structure coefficients for different initial metallicities for use in stellar analysis

NASA Astrophysics Data System (ADS)

Inlek, Gulay; Budding, Edwin; Demircan, Osman

2017-09-01

Internal structure coefficients for zero age Main Sequence (ZAMS) model stars with different initial metallicities are presented. A series of (Eggleton) stellar models with masses between 1-40 M_{⊙} and metallicities Z=0.0001, Z=0.001, Z=0.004, Z=0.01, Z=0.02, and Z=0.03 were used. We have also calculated the same coefficients for a recommended solar metallicity value Z=0.0134 (Asplund et al. in Annu. Rev. Astron. Astrophys. 47:481, 2009). For each model, values of the internal structure constants k2, k3, k4 and related coefficients have been derived by numerically integrating Radau's equation with the (FORTRAN) program RADAU. The (Eggleton) stellar models used come from the ` EZ-Web' compilation of the Dept. of Astronomy, University of Wisconsin, Madison. The calculations follow the procedure given by Inlek and Budding (Astrophys. Space Sci. 342:365, 2012). These new results were compared with others in the literature. We deduce that the current state of theoretical evaluation of structure coefficients is generally in sufficient agreement with data obtained from apsidal advance rates of selected well-observed eccentric eclipsing binary stars at the present time, given the probable errors of the latter. However, new results coming from more precise and extensive data sets in the wake of the Kepler Mission, or similar future surveys, may call for further theoretical specification or refinement. The derivation of structure coefficients from observations of apsidal motion in close eccentric binary systems requires specification of relevant parameters from light curve analysis. A self-consistent treatment then implies inclusion of the structure coefficients within the fitting function of such analysis.

Visibility graph analysis on quarterly macroeconomic series of China based on complex network theory

NASA Astrophysics Data System (ADS)

Wang, Na; Li, Dong; Wang, Qiwen

2012-12-01

The visibility graph approach and complex network theory provide a new insight into time series analysis. The inheritance of the visibility graph from the original time series was further explored in the paper. We found that degree distributions of visibility graphs extracted from Pseudo Brownian Motion series obtained by the Frequency Domain algorithm exhibit exponential behaviors, in which the exponential exponent is a binomial function of the Hurst index inherited in the time series. Our simulations presented that the quantitative relations between the Hurst indexes and the exponents of degree distribution function are different for different series and the visibility graph inherits some important features of the original time series. Further, we convert some quarterly macroeconomic series including the growth rates of value-added of three industry series and the growth rates of Gross Domestic Product series of China to graphs by the visibility algorithm and explore the topological properties of graphs associated from the four macroeconomic series, namely, the degree distribution and correlations, the clustering coefficient, the average path length, and community structure. Based on complex network analysis we find degree distributions of associated networks from the growth rates of value-added of three industry series are almost exponential and the degree distributions of associated networks from the growth rates of GDP series are scale free. We also discussed the assortativity and disassortativity of the four associated networks as they are related to the evolutionary process of the original macroeconomic series. All the constructed networks have “small-world” features. The community structures of associated networks suggest dynamic changes of the original macroeconomic series. We also detected the relationship among government policy changes, community structures of associated networks and macroeconomic dynamics. We find great influences of government policies in China on the changes of dynamics of GDP and the three industries adjustment. The work in our paper provides a new way to understand the dynamics of economic development.

Electrical Power Generated from Tidal Currents and Delivered to USCG Station Eastport, ME

DTIC Science & Technology

2011-01-21

35 Theory of Operation The ORPC Pre-Commercial Beta Turbine Generator Unit (“Beta TGU”) uses a hydrokinetic cross flow turbine based on Darrieus ...development in the wind turbine industry. The power coefficient (a measure of energy extraction effectiveness) is defined as follows: 31 2 turbine ...stream area of the device. Axial flow wind turbines have demonstrated power coefficients to an estimated 48% which approaches the theoretical “Betz

Solidification and Morphological Evolution of Al-Si Eutectics in Convector-Diffusive Conditions

NASA Technical Reports Server (NTRS)

Singh, N. B.; Su, Ching Hua; Arnold, Brad; Choa, Fow-Sen; Mandal, K. D.

2017-01-01

The Al-Si material system is an important and has been studied for over half century with a focus on industrial applications in high strength and high conductivity alloys. A great deal of researches have been focused on controlling the morphology and hence performance through the addition of small impurities and by processing conditions. Most of the structure-property correlations are based on the post solidified micromorphology and growth conditions. This material system is unique and has been explored for heat spreader, controlling coefficient of expansion by adjusting composition of silicon and in designing composites. The Al-Si system is very interesting system for understanding the dendritic (Al-rich side) eutectic transition. Recently this system has been of great interest because of its applications in designing heat spreader, low temperature flux to grow SiC large substrates and in controlling the coefficient of expansion of Al-based alloys. We have performed extensive experiments to understand eutectic transition and to understand the morphological evolution in presence of impurities. We will discuss the results of dendritic transition into faceted long grains in convector-diffusive conditions. In this presentation we will present morphological transition in presence of carbon impurity and development of novel morphology.

On the propagation of elasto-thermodiffusive surface waves in heat-conducting materials

NASA Astrophysics Data System (ADS)

Sharma, J. N.; Sharma, Y. D.; Sharma, P. K.

2008-09-01

The present paper deals with the study of the propagation of Rayleigh surface waves in homogeneous isotropic, thermodiffusive elastic half-space. After developing the formal solution of the model, the secular equations for stress free, thermally insulated or isothermal, and isoconcentrated boundary conditions of the half-space have been obtained. The secular equations have been solved by using irreducible Cardano's method with the help of DeMoivre's theorem in order to obtain phase velocity and attenuation coefficient of waves under consideration. The motion of the surface particles during the Rayleigh surface wave propagation is also discussed and found to be elliptical in general. The inclinations of wave normal with the major axis of the elliptical path of a typical particle have also been computed. Finally, the numerically simulated results regarding phase velocity, attenuation coefficient, specific loss and thermo-mechanical coupling factors of thermoelastic diffusive waves have been obtained and presented graphically. Some very interesting and useful characteristics of surface acoustic waves have been obtained, which may help in improving the fabrication quality of optical and electronic devices in addition to construction and design of materials such as semiconductors and composite structures. Therefore, this work finds applications in the geophysics and electronics industry.

Using polyacrylate-coated SPME fibers to quantify sorption of polar and ionic organic contaminants to dissolved organic carbon.

PubMed

Haftka, Joris J-H; Scherpenisse, Peter; Jonker, Michiel T O; Hermens, Joop L M

2013-05-07

A passive sampling method using polyacrylate-coated solid-phase microextraction (SPME) fibers was applied to determine sorption of polar and ionic organic contaminants to dissolved organic carbon (DOC). The tested contaminants included pharmaceuticals, industrial chemicals, hormones, and pesticides and represented neutral, anionic, and cationic structures. Prior to the passive sampler application, sorption of the chemicals to the fibers was characterized. This was needed in order to accurately translate concentrations measured in fibers to freely dissolved aqueous concentrations during the sorption tests with DOC. Sorption isotherms of neutral compounds to the fiber were linear, whereas isotherms of basic chemicals covered a nonlinear and a linear range. Sorption of acidic and basic compounds to the fiber was pH-dependent and was dominated by sorption of the neutral sorbate species. Fiber- and DOC-water partition coefficients of neutral compounds were both linearly related to octanol-water partition coefficients (log Kow). The results of this study show that polyacrylate fibers can be used to quantify sorption to DOC of neutral and ionic contaminants, having multiple functional groups and spanning a wide hydrophobicity range (log Kow = 2.5-7.5).

Growth and characterization of barium complex of 1,3,5-triazinane-2,4,6-trione in gel: a corrosion inhibiting material

NASA Astrophysics Data System (ADS)

Divya, R.; Nair, Lekshmi P.; Bijini, B. R.; Nair, C. M. K.; Babu, K. Rajendra

2018-05-01

Good quality prismatic crystals of industrially applicable corrosion inhibiting barium complex of 1,3,5-triazinane-2,4,6-trione have been grown by conventional gel method. The crystal structure, packing, and nature of bonds are revealed in the single crystal X-ray diffraction analysis. The crystal has a three-dimensional polymeric structure having a triclinic crystal system with the space group P-1. The powder X-ray diffraction analysis confirms its crystalline nature. The functional groups present in the crystal are identified by Fourier transform infrared spectroscopy. Elemental analysis confirms the stoichiometry of the elements present in the complex. Thermogravimetric analysis and differential thermal analysis reveal its good thermal stability. The optical properties like band gap, refractive index and extinction coefficient are evaluated from the UV-visible spectral analysis. The singular property of the material, corrosion inhibition efficiency achieved by the adsorption of the sample molecules is determined by the weight loss method.

Giant piezoelectricity of monolayer group IV monochalcogenides: SnSe, SnS, GeSe, and GeS

NASA Astrophysics Data System (ADS)

Fei, Ruixiang; Li, Wenbin; Li, Ju; Yang, Li

2015-10-01

We predict enormous, anisotropic piezoelectric effects in intrinsic monolayer group IV monochalcogenides (MX, M=Sn or Ge, X=Se or S), including SnSe, SnS, GeSe, and GeS. Using first-principle simulations based on the modern theory of polarization, we find that their piezoelectric coefficients are about one to two orders of magnitude larger than those of other 2D materials, such as MoS2 and GaSe, and bulk quartz and AlN which are widely used in industry. This enhancement is a result of the unique "puckered" C2v symmetry and electronic structure of monolayer group IV monochalcogenides. Given the achieved experimental advances in the fabrication of monolayers, their flexible character, and ability to withstand enormous strain, these 2D structures with giant piezoelectric effects may be promising for a broad range of applications such as nano-sized sensors, piezotronics, and energy harvesting in portable electronic devices.

Structural Investigation of Phosphorus in CaO-SiO2-P2O5 Ternary Glass

NASA Astrophysics Data System (ADS)

Wang, Zhanjun; Cai, Shengjia; Zhang, Mei; Guo, Min; Zhang, Zuotai

2017-04-01

The system of CaO-SiO2-P2O5 ternary glass is not only among the major constituents of steelmaking slags in iron and steel industry, but also play a significant role in other industrial process, such as chemical engineering and glass industry. In the present study, the structure of CaO-SiO2-P2O5 ternary glass with varying P2O5 content from 0 to 15 wt pct at a fixed CaO/SiO2 = 1.4 was investigated using molecular dynamics (MD) simulation combined with X-ray photoelectron spectroscopy and Raman spectra techniques. The results indicated that P5+ ions have a higher affinity to Ca2+ ions which are then stripped away from the silicate network with the addition of P2O5, resulting in the formation of Ca-O-P and Si-O-Si linkages. In addition, almost all P5+ ions displayed as {{Q}}_{{P}}0 ( {{Q}}_{{P}}n , n is the number of bridging oxygen in one [PO4]-tetrahedra units) and a small fraction of P5+ ions behave as {{Q}}_{{P}}1 (P-O-P) and P-O-Si. The enhanced degree of polymerization can be detected from the increase of {{X}}_{{Si}}3 and X_{{P}}1 /X_{{P}}0 (mole fraction of {{Q}}_{{Si}}i or {{Q}}_{{P}}i ). Furthermore, the ratio of Raman scattering coefficients for Q_{{Si}}i /Q_{{Si}}1 and Q_{{P}}i /Q_{{P}}1 were determined by combining MD simulated result with Raman spectra, which were considered to be suitable to the present study.

Reflectors and tuning elements for widely-tunable GaAs-based sampled grating DBR lasers

NASA Astrophysics Data System (ADS)

Brox, O.; Wenzel, H.; Della Case, P.; Tawfieq, M.; Sumpf, B.; Weyers, M.; Knigge, A.

2018-02-01

Widely-tunable lasers without moving parts are attractive light sources for sensors in industry and biomedicine. In contrast to InP based sampled grating (SG) distributed Bragg reflector (DBR) diode lasers which are commercially available, shorter wavelength GaAs SG-DBR lasers are still under development. One reason is the difficulty to integrate gratings with coupling coefficients that are high enough for functional grating bursts with lengths below 10 μm. Recently we have demonstrated > 20 nm wide quasi-continuous tuning with a GaAs based SG-DBR laser emitting around 975 nm. Wavelength selective reflectors are realized with SGs having different burst periods for the front and back mirrors. Thermal tuning elements (resistors) which are placed on top of the SG allow the control of the spectral positions of the SG reflector combs and hence to adjust the Vernier mode. In this work we characterize subsections of the developed SG-DBR laser to further improve its performance. We study the impact of two different vertical structures (with vertical far field FWHMs of 41° and 24°) and two grating orders on the coupling coefficient. Gratings with coupling coefficients above 350 cm-1 have been integrated into SG-DBR lasers. We also examine electronic tuning elements (a technique which is typically applied in InP based SG-DBR lasers and allows tuning within nanoseconds) and discuss the limitations in the GaAs material system

P-type Al-doped Cr-deficient CrN thin films for thermoelectrics

NASA Astrophysics Data System (ADS)

le Febvrier, Arnaud; Van Nong, Ngo; Abadias, Gregory; Eklund, Per

2018-05-01

Thermoelectric properties of chromium nitride (CrN)-based films grown on c-plane sapphire by dc reactive magnetron sputtering were investigated. In this work, aluminum doping was introduced in CrN (degenerate n-type semiconductor) by co-deposition. Under the present deposition conditions, over-stoichiometry in nitrogen (CrN1+δ) rock-salt structure is obtained. A p-type conduction is observed with nitrogen-rich CrN combined with aluminum doping. The Cr0.96Al0.04N1.17 film exhibited a high Seebeck coefficient and a sufficient power factor at 300 °C. These results are a starting point for designing p-type/n-type thermoelectric materials based on chromium nitride films, which are cheap and routinely grown on the industrial scale.

Properties of Diamond-Like Carbon Films Synthesized by Dual-Target Unbalanced Magnetron Sputtering

NASA Astrophysics Data System (ADS)

Liu, Cui; Li, Guo-Qing; Gou, Wei; Mu, Zong-Xin; Zhang, Cheng-Wu

2004-11-01

Smooth, dense and uniform diamond-like carbon films (DLC films) for industrial applications have successfully been prepared by dual-target unbalanced magnetron sputtering and the DLC characteristics of the films are confirmed by Raman spectra. It is found that the sputtering current of target plays an important role in the DLC film deposition. Deposition rate of 3.5 μm/h is obtained by using the sputtering current of 30 A. The friction coefficient of the films is 0.2-0.225 measured by using a pin-on-disc microtribometer. The structure of the films tends to have a growth of sp3 bonds content at high sputtering current. The compressive residual stress in the films increases with the increasing sputtering current of the target.

Interactions in charged colloidal suspensions: A molecular dynamics simulation study

NASA Astrophysics Data System (ADS)

Padidela, Uday Kumar; Behera, Raghu Nath

2017-07-01

Colloidal suspensions are extensively used in everyday life and find several applications in the pharmaceutical, chemical, food industries, etc. We present the classical molecular dynamics simulation results of the structural and transport properties of charged colloidal suspensions as a function of its size, charge and concentration. The system is viewed as a two-component (colloids and counterions) primitive model consisting of spherical colloid particle (macroion) and the counterions (micro-particles), which are treated explicitly. The solvent is treated as dielectric continuum. A systematic trend in the radial distribution functions g(r), potential of mean force W(r), different thermodynamic properties and diffusion coefficients is obtained as a function of colloid charge, size and concentration. An attractive minimum in W(r) is obtained at short interparticle distance.

The effects of common risk factors on stock returns: A detrended cross-correlation analysis

NASA Astrophysics Data System (ADS)

Ruan, Qingsong; Yang, Bingchan

2017-10-01

In this paper, we investigate the cross-correlations between Fama and French three factors and the return of American industries on the basis of cross-correlation statistic test and multifractal detrended cross-correlation analysis (MF-DCCA). Qualitatively, we find that the return series of Fama and French three factors and American industries were overall significantly cross-correlated based on the analysis of a statistic. Quantitatively, we find that the cross-correlations between three factors and the return of American industries were strongly multifractal, and applying MF-DCCA we also investigate the cross-correlation of industry returns and residuals. We find that there exists multifractality of industry returns and residuals. The result of correlation coefficients we can verify that there exist other factors which influence the industry returns except Fama three factors.

Model-based damage evaluation of layered CFRP structures

NASA Astrophysics Data System (ADS)

Munoz, Rafael; Bochud, Nicolas; Rus, Guillermo; Peralta, Laura; Melchor, Juan; Chiachío, Juan; Chiachío, Manuel; Bond, Leonard J.

2015-03-01

An ultrasonic evaluation technique for damage identification of layered CFRP structures is presented. This approach relies on a model-based estimation procedure that combines experimental data and simulation of ultrasonic damage-propagation interactions. The CFPR structure, a [0/90]4s lay-up, has been tested in an immersion through transmission experiment, where a scan has been performed on a damaged specimen. Most ultrasonic techniques in industrial practice consider only a few features of the received signals, namely, time of flight, amplitude, attenuation, frequency contents, and so forth. In this case, once signals are captured, an algorithm is used to reconstruct the complete signal waveform and extract the unknown damage parameters by means of modeling procedures. A linear version of the data processing has been performed, where only Young modulus has been monitored and, in a second nonlinear version, the first order nonlinear coefficient β was incorporated to test the possibility of detection of early damage. The aforementioned physical simulation models are solved by the Transfer Matrix formalism, which has been extended from linear to nonlinear harmonic generation technique. The damage parameter search strategy is based on minimizing the mismatch between the captured and simulated signals in the time domain in an automated way using Genetic Algorithms. Processing all scanned locations, a C-scan of the parameter of each layer can be reconstructed, obtaining the information describing the state of each layer and each interface. Damage can be located and quantified in terms of changes in the selected parameter with a measurable extension. In the case of the nonlinear coefficient of first order, evidence of higher sensitivity to damage than imaging the linearly estimated Young Modulus is provided.

Lubricating coating prepared by PIIID on a forming tool

NASA Astrophysics Data System (ADS)

Martinatti, J. F.; Santos, L. V.; Durrant, S. F.; Cruz, N. C.; Rangel, E. C.

2012-06-01

In this work, the performance of a-C:H films produced by the hybrid Plasma Immersion Ion Implantation and Deposition technique as lubricating layers for a steel forming tool has been investigated. Hardened steel (AISI M2, 64 HRC) plates coated with a commercial TiN layer were used as substrates and the films were deposited in a vacuum chamber fitted with two parallel-plate electrodes. The discharges were generated in atmospheres composed of 91% C2H2 and 9% Ar by the application of radiofrequency power (13.56 MHz, 100 W) to the upper electrode while the lower one, also used as the sample holder, was biased with high voltage negative pulses (3.6 kV, 30 μs, 300 Hz). A deposition time of 840 s was used. The effects of the gas pressure, p, on thickness, molecular structure, wettability, surface morphology and topography, hardness and friction coefficient of the films were investigated. Film thickness increased from 0.3 to 0.5 μm when p was increased from 2.7 to 16.5 Pa. Generally, the films were slightly hydrophilic, with contact angles of around 84°, and the deposition decreased the roughness of the steel. A polymer-like structure was detected in high pressure depositions and an amorphous carbon structure derived from the low pressure procedures. Hardness decreased from 8.2 to 7.0 GPa with increasing p. Improvement in tribological performance was indicated by the fall in the friction coefficient from 0.5 to 0.2 as the deposition pressure was reduced. Operating at the latter value (of μ) would lead to a significant reduction in wear and hence to significant economy in diverse industrial applications.

Development and Validation of a Practical Instrument for Injury Prevention: The Occupational Safety and Health Monitoring and Assessment Tool (OSH-MAT).

PubMed

Sun, Yi; Arning, Martin; Bochmann, Frank; Börger, Jutta; Heitmann, Thomas

2018-06-01

The Occupational Safety and Health Monitoring and Assessment Tool (OSH-MAT) is a practical instrument that is currently used in the German woodworking and metalworking industries to monitor safety conditions at workplaces. The 12-item scoring system has three subscales rating technical, organizational, and personnel-related conditions in a company. Each item has a rating value ranging from 1 to 9, with higher values indicating higher standard of safety conditions. The reliability of this instrument was evaluated in a cross-sectional survey among 128 companies and its validity among 30,514 companies. The inter-rater reliability of the instrument was examined independently and simultaneously by two well-trained safety engineers. Agreement between the double ratings was quantified by the intraclass correlation coefficient and absolute agreement of the rating values. The content validity of the OSH-MAT was evaluated by quantifying the association between OSH-MAT values and 5-year average injury rates by Poisson regression analysis adjusted for the size of the companies and industrial sectors. The construct validity of OSH-MAT was examined by principle component factor analysis. Our analysis indicated good to very good inter-rater reliability (intraclass correlation coefficient = 0.64-0.74) of OSH-MAT values with an absolute agreement of between 72% and 81%. Factor analysis identified three component subscales that met exactly the structure theory of this instrument. The Poisson regression analysis demonstrated a statistically significant exposure-response relationship between OSH-MAT values and the 5-year average injury rates. These analyses indicate that OSH-MAT is a valid and reliable instrument that can be used effectively to monitor safety conditions at workplaces.

Nutrient digestibility response to sugarcane bagasse addition and corn particle size in normal and high Na diets for broilers.

PubMed

Kheravii, S K; Swick, R A; Choct, M; Wu, S-B

2018-04-01

Improving diet digestibility is important to the broiler industry. Therefore, this study focused on optimizing the physical structure of feed ingredients and addition of dietary fiber as strategies to improve nutrient digestibility in low and high sodium diets. A total of 672 day-old Ross 308 male broilers was allocated to 48 pens using a 2 × 2 × 2 factorial arrangement of treatments with 2 particle sizes of corn (coarse 3,576 μm or fine 1,113 μm geometric mean diameter), 2 levels of sugarcane bagasse (SB) (0 or 2%), and 2 levels of Na (0.16 or 0.4%). Protein digestibility coefficient was measured using pooled distal ileal digesta of 3 birds per pen on d 24. Meanwhile, starch and gross energy digestibility coefficients were measured using pooled duodenal, distal jejunal, and distal ileal digesta of 3 birds per pen on d 24. Coarsely ground corn (CC) resulted in improved ileal protein digestibility (P < 0.05). Addition of 2% SB increased starch digestibility in the duodenum (P < 0.05), distal jejunum (P < 0.001), and distal ileum (P < 0.001), and increased protein digestibility in distal ileum (P < 0.01). A significant particle size × SB × Na interaction was observed for ileal energy digestibility (P < 0.05). The SB increased ileal energy digestibility only in birds fed the diet with finely ground corn (FC) and 0.16% Na. These findings demonstrate that SB and CC are able to improve nutrient digestibility. It can be recommended for the poultry industry to use SB and coarsely ground corn in feed to improve the utilization of nutrients.

Temporal variations of heavy metals in coral Porites lutea from Guangdong Province, China: Influences from industrial pollution, climate and economic factors

USGS Publications Warehouse

Peng, Z.; Liu, J.; Zhou, C.; Nie, B.; Chen, T.

2006-01-01

The correlation coefficients among the metals and climatic and economic factors indicate that the metals Ni, Zn, and Cd behave similarly. Copper and Mn are positively correlated, and cobalt is negatively correlated with Cr, Ni, Zn, and Cd. Lead is not correlated with any other metals but is correlated with sea surface water temperature, air temperature, GDP and industrial-agricultural production in Dianbai County. Lead in corals is related to the enhanced pollution level of ocean waters as a result of increased industrial activities.

Industrial Computer Codes

NASA Technical Reports Server (NTRS)

Shapiro, Wilbur

1996-01-01

This is an overview of new and updated industrial codes for seal design and testing. GCYLT (gas cylindrical seals -- turbulent), SPIRALI (spiral-groove seals -- incompressible), KTK (knife to knife) Labyrinth Seal Code, and DYSEAL (dynamic seal analysis) are covered. CGYLT uses G-factors for Poiseuille and Couette turbulence coefficients. SPIRALI is updated to include turbulence and inertia, but maintains the narrow groove theory. KTK labyrinth seal code handles straight or stepped seals. And DYSEAL provides dynamics for the seal geometry.

Synthetic aperture radar imagery of airports and surrounding areas: Philadelphia Airport

NASA Technical Reports Server (NTRS)

Onstott, Robert G.; Gineris, Denise J.

1990-01-01

The statistical description of ground clutter at an airport and in the surrounding area is addressed. These data are being utilized in a program to detect microbursts. Synthetic Aperture Radar (SAR) data were collected at the Philadelphia Airport. These data and the results of the clutter study are described. This 13 km x 10 km scene was imaged at 9.38 GHz and HH-polarization and contained airport grounds and facilities (6 percent), industrial (14 percent), residential (14 percent), fields (10 percent), forest (8 percent), and water (33 percent). Incidence angles ranged from 40 to 84 deg. Even at the smallest incidence angles, the distributed targets such as forest, fields, water, and residential rarely had mean scattering coefficients greater than -10 dB. Eighty-seven percent of the image had scattering coefficients less than -17.5 dB. About 1 percent of the scattering coefficients exceeded 0 dB, with about 0.1 percent above 10 dB. Sources which produced the largest cross sections were largely confined to the airport grounds and areas highly industrialized. The largest cross sections were produced by observing broadside large buildings surrounded by smooth surfaces.

Measurements of octanol-air partition coefficients, vapor pressures and vaporization enthalpies of the (E) and (Z) isomers of the 2-ethylhexyl 4-methoxycinnamate as parameters of environmental impact assessment.

PubMed

Pegoraro, César N; Chiappero, Malisa S; Montejano, Hernán A

2015-11-01

2-Ethylhexyl 4-methoxycinnamate is one of the UVB blocking agents more widely used in a variety of industrial fields. There are more than one hundred industrial suppliers worldwide. Given the enormous annual consumption of octinoxate, problems that arise due to the accumulation of this compound in nature should be taken into consideration. The GC-RT was used in this work with the aim of determining the vapor pressure, enthalpies of vaporization and octanol-air partition coefficient, for the BBP, DOP, E- and Z-EHMC esters. The results showed that Z-EHMC is almost five times more volatile than E-EHMC. Moreover, BBP, Z-EHMC and E-EHMC can be classified as substances with a relatively low mobility since they lie within the range of 810 and log(PL/Pa)<-4, therefore, a low mobility can be expected. From these parameters, their particle-bound fraction and gas-particle partition coefficient were also derived. Copyright © 2015 Elsevier Ltd. All rights reserved.

Estimation of water diffusion coefficient into polycarbonate at different temperatures using numerical simulation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nasirabadi, P. Shojaee; Jabbari, M.; Hattel, J. H.

2016-06-08

Nowadays, many electronic systems are exposed to harsh conditions of relative humidity and temperature. Mass transport properties of electronic packaging materials are needed in order to investigate the influence of moisture and temperature on reliability of electronic devices. Polycarbonate (PC) is widely used in the electronics industry. Thus, in this work the water diffusion coefficient into PC is investigated. Furthermore, numerical methods used for estimation of the diffusion coefficient and their assumptions are discussed. 1D and 3D numerical solutions are compared and based on this, it is shown how the estimated value can be different depending on the choice ofmore » dimensionality in the model.« less

SEADS 3.0 Sectoral Energy/Employment Analysis and Data System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Roop, Joseph M.; Anderson, David A.; Schultz, Robert W.

2007-12-17

SEADS 3.0, the Sectoral Energy/Employment Analysis and Data System, is a revision and upgrading of SEADS--PC, a software package designed for the analysis of policy that could be described by modifying final demands of consumer, businesses, or governments (Roop, et al., 1995). If a question can be formulated so that implications can be translated into changes in final demands for goods and services, then SEADS 3.0 provides a quick and easy tool to assess preliminary impacts. And SEADS 3.0 should be considered just that: a quick and easy way to get preliminary results. Often a thorough answer, even to suchmore » a simple question as, “What would be the effect on U. S. energy use and employment if the Federal Government doubled R&D expenditures?” requires a more sophisticated analytical framework than the input-output structure embedded in SEADS 3.0. This tool uses a static, input-output model to assess the impacts of changes in final demands on first industry output, then employment and energy use. The employment and energy impacts are derived by multiplying the industry outputs (derived from the changed final demands) by industry-specific energy and employment coefficients. The tool also allows for the specification of regional or state employment impacts, though this option is not available for energy impacts.« less

Study of flutter related computational procedures for minimum weight structural sizing of advanced aircraft, supplemental data

NASA Technical Reports Server (NTRS)

Oconnell, R. F.; Hassig, H. J.; Radovcich, N. A.

1975-01-01

Computational aspects of (1) flutter optimization (minimization of structural mass subject to specified flutter requirements), (2) methods for solving the flutter equation, and (3) efficient methods for computing generalized aerodynamic force coefficients in the repetitive analysis environment of computer-aided structural design are discussed. Specific areas included: a two-dimensional Regula Falsi approach to solving the generalized flutter equation; method of incremented flutter analysis and its applications; the use of velocity potential influence coefficients in a five-matrix product formulation of the generalized aerodynamic force coefficients; options for computational operations required to generate generalized aerodynamic force coefficients; theoretical considerations related to optimization with one or more flutter constraints; and expressions for derivatives of flutter-related quantities with respect to design variables.

Coefficient Alpha: A Reliability Coefficient for the 21st Century?

ERIC Educational Resources Information Center

Yang, Yanyun; Green, Samuel B.

2011-01-01

Coefficient alpha is almost universally applied to assess reliability of scales in psychology. We argue that researchers should consider alternatives to coefficient alpha. Our preference is for structural equation modeling (SEM) estimates of reliability because they are informative and allow for an empirical evaluation of the assumptions…

Entropy-theory-based study on the relationship between land use structure and industry system: a case study of the eastern Hubei metropolitan area

NASA Astrophysics Data System (ADS)

Su, Lilan; Liu, Yanfang; Gao, Xiaoyong

2009-10-01

During the process of economic growth, the industry structure transforms at different developing sections and that industrial composition as well as each department interior demand for land resources would reflect on land-use structure reform. This paper takes Hubei as the research zone, through a consecutive time sequence of 10 years period (1996-2005) just before and after the 1 plus 8 Eastern Hubei Metropolitan Area project, a quantitative study of the correlation between the industry structure and land-use structure is made based on the entropy theory. According to the classification of industrial composition, the land-use structure here is also redefined into four types as Land Use for Primary Industry, Land Use for Secondary Industry, Land Use for Tertiary Industry, and Land Use for Potential Reserve, in the aim that it should model new methods for researching the relationship of industry structure and land-use structure, and the instinct driving force would be presented more evidently at the same time. The outcomes indicate that the change of land-use structure has close relationship with the structure of industry composition; the trend of information entropy in Hubei mostly keeps increasing during the past 10 years which predicating the symmetrical degree of land-use structure is gradually built; and Eastern Hubei Metropolitan Area is of favorable power far superiority other units within province in promoting regional development, yet land-use structure adjustments are still not stable and a optimal mode of land use needs further approach.

Fixed-bed column studies of total organic carbon removal from industrial wastewater by use of diatomite decorated with polyethylenimine-functionalized pyroxene nanoparticles.

PubMed

Hethnawi, Afif; Manasrah, Abdallah D; Vitale, Gerardo; Nassar, Nashaat N

2018-03-01

In this study, a fixed-bed column adsorption process was employed to remove organic pollutants from a real industrial wastewater effluent using polyethylenimine-functionalized pyroxene nanoparticles (PEI-PY) embedded into Diatomite at very low mass percentage. Various dynamic parameters (e.g., inlet concentration, inlet flow rate, bed height, and PEI-nanoparticle concentration in Diatomite, (%nps)) were investigated to determine the breakthrough behavior. The obtained breakthrough curves were fit with a convection-dispersion model to determine the characteristic parameters based on mass transfer phenomena. The axial dispersion coefficient (D L ) and group of dimensionless numbers; including Renold number (Re), Schmidt number (Sc), and Sherwood number (Sh) were all determined and correlated by Wilson-Geankoplis correlation that was used to estimate the external film diffusion coefficients (Kc) at 0.0015 < Re<55. Copyright © 2017 Elsevier Inc. All rights reserved.

Non-parametric wall model and methods of identifying boundary conditions for moments in gas flow equations

NASA Astrophysics Data System (ADS)

Liao, Meng; To, Quy-Dong; Léonard, Céline; Monchiet, Vincent

2018-03-01

In this paper, we use the molecular dynamics simulation method to study gas-wall boundary conditions. Discrete scattering information of gas molecules at the wall surface is obtained from collision simulations. The collision data can be used to identify the accommodation coefficients for parametric wall models such as Maxwell and Cercignani-Lampis scattering kernels. Since these scattering kernels are based on a limited number of accommodation coefficients, we adopt non-parametric statistical methods to construct the kernel to overcome these issues. Different from parametric kernels, the non-parametric kernels require no parameter (i.e. accommodation coefficients) and no predefined distribution. We also propose approaches to derive directly the Navier friction and Kapitza thermal resistance coefficients as well as other interface coefficients associated with moment equations from the non-parametric kernels. The methods are applied successfully to systems composed of CH4 or CO2 and graphite, which are of interest to the petroleum industry.

The Aerodynamic and Dynamic Loading of a Slender Structure by an Impacting Tornado-Like Vortex: The Influence of Relative Vortex-to-Structure Size on Structural Loading

NASA Astrophysics Data System (ADS)

Strasser, Matthew N.

Structural loading produced by an impacting vortex is a hazardous phenomenon that is encountered in numerous applications ranging from the destruction of residences by tornados to the chopping of tip vortices by rotors. Adequate design of structures to resist vortex-induced structural loading necessitates study of the phenomenon that control the structural loading produced by an impacting vortex. This body of work extends the current knowledge base of vortex-structure interaction by evaluating the influence of the relative vortex-to-structure size on the structural loading that the vortex produces. A computer model is utilized to directly simulate the two-dimensional impact of an impinging vortex with a slender, cylindrical structure. The vortex's tangential velocity profile (TVP) is defined by a normalization of the Vatistas analytical (TVP) which realistically replicates the documented spectrum of measured vortex TVPs. The impinging vortex's maximum tangential velocity is fixed, and the vortex's critical radius is incremented from one to one-hundred times the structure's diameter. When the impinging vortex is small, it interacts with vortices produced on the structure by the free stream, and maximum force coefficient amplitudes vary by more than 400% when the impinging vortex impacts the structure at different times. Maximum drag and lift force coefficient amplitudes reach asymptotic values as the impinging vortex's size increases that are respectively 94.77% and 10.66% less than maximum force coefficients produced by an equivalent maximum velocity free stream. The vortex produces maximum structural loading when its path is shifted above the structure's centerline, and maximum drag and lift force coefficients are respectively up to 4.80% and 34.07% greater than maximum force coefficients produced by an equivalent-velocity free stream. Finally, the dynamic load factor (DLF) concept is used to develop a generalized methodology to assess the dynamic amplification of a structure's response to vortex loading and to assess the dynamic loading threat that tornados pose. Typical civil and residential structures will not experience significant response amplification, but responses of very flexible structures may be amplified by up to 2.88 times.

Supplier selection in supply chain management using analytical network process for Indonesian cement industry

NASA Astrophysics Data System (ADS)

Ismail, A. H.; Mahardika, R. Z. Z.

2017-12-01

Supply chain management has increased more significance with the impact of globalization. In the present worldwide market, well-managed supply chain is a standout amongst the most vital requirement to be more competitive in the market. For any organization incorporate cement industry, the most critical decision in initial process of supply chain management is to buy products, materials or services from suppliers. So the role of suppliers is irrefutable important in the global aggressive markets. Appropriate decision of supplier selection can lead to reducing cost in supply chain management. However, it is becoming more complex because of existing various criteria and involving the suitable experts in the company to make valid decision in accordance with its criteria. In this study, the supplier selection of an Indonesia’s leading cement company is analyzed by using one of the popular multi-criteria decision making method, Saaty’s analytical network process (ANP). It is employed for the selection of the best alternative among three suppliers of pasted bag. Supplier with the highest rank comes from several major steps from building the relationship between various criteria to rating the alternatives with the help of experts from the company. The results show that, Communication capability, Flexible payment terms, Ability to meet delivery quantities are the most important criteria in the pasted bag supplier selection in Indonesian cement industry with 0.155, 0.110 and 0.1 ANP coefficient respectively. And based on the ANP coefficient values in limit supermatrix, the A2 or supplier 2 had the highest score with 64.7% or 0.13 ANP coefficient.

Silicide/Silicon Hetero-Junction Structure for Thermoelectric Applications.

PubMed

Jun, Dongsuk; Kim, Soojung; Choi, Wonchul; Kim, Junsoo; Zyung, Taehyoung; Jang, Moongyu

2015-10-01

We fabricated silicide/silicon hetero-junction structured thermoelectric device by CMOS process for the reduction of thermal conductivity with the scatterings of phonons at silicide/silicon interfaces. Electrical conductivities, Seebeck coefficients, power factors, and temperature differences are evaluated using the steady state analysis method. Platinum silicide/silicon multilayered structure showed an enhanced Seebeck coefficient and power factor characteristics, which was considered for p-leg element. Also, erbium silicide/silicon structure showed an enhanced Seebeck coefficient, which was considered for an n-leg element. Silicide/silicon multilayered structure is promising for thermoelectric applications by reducing thermal conductivity with an enhanced Seebeck coefficient. However, because of the high thermal conductivity of the silicon packing during thermal gradient is not a problem any temperature difference. Therefore, requires more testing and analysis in order to overcome this problem. Thermoelectric generators are devices that based on the Seebeck effect, convert temperature differences into electrical energy. Although thermoelectric phenomena have been used for heating and cooling applications quite extensively, it is only in recent years that interest has increased in energy generation.

The Study on Neuro-IE Management Software in Manufacturing Enterprises. -The Application of Video Analysis Technology

NASA Astrophysics Data System (ADS)

Bian, Jun; Fu, Huijian; Shang, Qian; Zhou, Xiangyang; Ma, Qingguo

This paper analyzes the outstanding problems in current industrial production by reviewing the three stages of the Industrial Engineering Development. Based on investigations and interviews in enterprises, we propose the new idea of applying "computer video analysis technology" to new industrial engineering management software, and add "loose-coefficient" of the working station to this software in order to arrange scientific and humanistic production. Meanwhile, we suggest utilizing Biofeedback Technology to promote further research on "the rules of workers' physiological, psychological and emotional changes in production". This new kind of combination will push forward industrial engineering theories and benefit enterprises in progressing towards flexible social production, thus it will be of great theory innovation value, social significance and application value.

Higher-order clustering in networks

NASA Astrophysics Data System (ADS)

Yin, Hao; Benson, Austin R.; Leskovec, Jure

2018-05-01

A fundamental property of complex networks is the tendency for edges to cluster. The extent of the clustering is typically quantified by the clustering coefficient, which is the probability that a length-2 path is closed, i.e., induces a triangle in the network. However, higher-order cliques beyond triangles are crucial to understanding complex networks, and the clustering behavior with respect to such higher-order network structures is not well understood. Here we introduce higher-order clustering coefficients that measure the closure probability of higher-order network cliques and provide a more comprehensive view of how the edges of complex networks cluster. Our higher-order clustering coefficients are a natural generalization of the traditional clustering coefficient. We derive several properties about higher-order clustering coefficients and analyze them under common random graph models. Finally, we use higher-order clustering coefficients to gain new insights into the structure of real-world networks from several domains.

Contribution of industrial density and socioeconomic status to the spatial distribution of thyroid cancer risk in Hangzhou, China.

PubMed

Fei, Xufeng; Lou, Zhaohan; Christakos, George; Liu, Qingmin; Ren, Yanjun; Wu, Jiaping

2018-02-01

The thyroid cancer (TC) incidence in China has increased dramatically during the last three decades. Typical in this respect is the case of Hangzhou city (China), where 7147 new TC cases were diagnosed during the period 2008-2012. Hence, the assessment of the TC incidence risk increase due to environmental exposure is an important public health matter. Correlation analysis, Analysis of Variance (ANOVA) and Poisson regression were first used to evaluate the statistical association between TC and key risk factors (industrial density and socioeconomic status). Then, the Bayesian maximum entropy (BME) theory and the integrative disease predictability (IDP) criterion were combined to quantitatively assess both the overall and the spatially distributed strength of the "exposure-disease" association. Overall, higher socioeconomic status was positively correlated with higher TC risk (Pearson correlation coefficient=0.687, P<0.01). Compared to people of low socioeconomic status, people of median and high socioeconomic status showed higher TC risk: the Relative Risk (RR) and associated 95% confidence interval (CI) were found to be, respectively, RR=2.29 with 95% CI=1.99 to 2.63, and RR=3.67 with 95% CI=3.22 to 4.19. The "industrial density-TC incidence" correlation, however, was non-significant. Spatially, the "socioeconomic status-TC" association measured by the corresponding IDP coefficient was significant throughout the study area: the mean IDP value was -0.12 and the spatial IDP values were consistently negative at the township level. It was found that stronger associations were distributed among residents mainly on a stripe of land from northeast to southwest (consisting mainly of sub-district areas). The "industrial density-TC" association measured by its IDP coefficient was spatially non-consistent. Socioeconomic status is an important indicator of TC risk factor in Hangzhou (China) whose effect varies across space. Hence, socioeconomic status shows the highest TC risk effect in sub-district areas. Copyright © 2017. Published by Elsevier B.V.

A Structural Modeling Approach to a Multilevel Random Coefficients Model.

ERIC Educational Resources Information Center

Rovine, Michael J.; Molenaar, Peter C. M.

2000-01-01

Presents a method for estimating the random coefficients model using covariance structure modeling and allowing one to estimate both fixed and random effects. The method is applied to real and simulated data, including marriage data from J. Belsky and M. Rovine (1990). (SLD)

X-ray fluorescence analysis of low concentrations metals in geological samples and technological products

NASA Astrophysics Data System (ADS)

Lagoida, I. A.; Trushin, A. V.

2016-02-01

For the past several years many nuclear physics methods of quantitative elemental analysis have been designed. Many of these methods have applied in different devices which have become useful and effective instrument in many industrial laboratories. Methods of a matter structure analysis are based on the intensity detection of the X-ray radiation from the nuclei of elements which are excited by external X-ray source. The production of characteristic X-rays involves transitions of the orbital electrons of atoms in the target material between allowed orbits, or energy states, associated with ionization of the inner atomic shells. One of these methods is X-ray fluorescence analysis, which is widespread in metallurgical and processing industries and is used to identify and measure the concentration of the elements in ores and minerals on a conveyor belt. Samples of copper ore with known concentrations of elements, were taken from the Ural deposit. To excite the characteristic X-rays radionuclide sources 109Cd, with half-life 461.4 days were used. After finding the calibration coefficients, control measurements of samples and averaging of overall samples were made. The measurement error did not exceed 3%.

Nondestructive Method For Measuring The Scattering Coefficient Of Bulk Material

NASA Astrophysics Data System (ADS)

Groenhuis, R. A. J.; ten Bosch, J. J.

1981-05-01

During demineralization and remineralization of dental enamel its structure changes resulting in a change of the absorption and scattering coefficients of the enamel. By measuring these coefficients during demineralization and remineralization these processes can be monitored in a non-destructive way. For this purpose an experimental arrangement was made: a fibre illuminates a spot on the sample with monochromatic light with a wave-length between 400 nm and 700 nm; a photomultiplier measures the luminance of the light back-scattered by the sample as a function of the distance from the measuring snot to the spot of illumination. In a Monte Carlo-model this luminance is simulated using the same geometry given the scattering and absorption coefficients in a sample. Then the scattering and absorption coefficients in the sample are determined by selecting the theoretical curve fitting the experimental one. Scattering coefficients below 10 mm-1 and absorption coefficients obtained with this method on calibration samples correspond well with those obtained with another method. Scattering coefficients above 10 mm-1 (paper samples) were measured ton low. This perhaps is caused by the anisotropic structure of paper sheets. The method is very suitable to measure the scattering and absorption coefficients of bulk materials.

Mechanics of fluid flow over compliant wrinkled polymeric surfaces

NASA Astrophysics Data System (ADS)

Raayai, Shabnam; McKinley, Gareth; Boyce, Mary

2014-03-01

Skin friction coefficients (based on frontal area) of sharks and dolphins are lower than birds, fish and swimming beetles. By either exploiting flow-induced changes in their flexible skin or microscale textures, dolphins and sharks can change the structure of the fluid flow around them and thus reduce viscous drag forces on their bodies. Inspired by this ability, investigators have tried using compliant walls and riblet-like textures as drag reduction methods in aircraft and marine industries and have been able to achieve reductions up to 19%. Here we investigate flow-structure interaction and wrinkling of soft polymer surfaces that can emulate shark riblets and dolphin's flexible skin. Wrinkling arises spontaneously as the result of mismatched deformation of a thin stiff coating bound to a thick soft elastic substrate. Wrinkles can be fabricated by controlling the ratio of the stiffness of the coating and substrate, the applied displacement and the thickness of the coating. In this work we will examine the evolution in the kinematic structures associated with steady viscous flow over the polymer wrinkled surfaces and in particular compare the skin friction with corresponding results for flow over non-textured and rigid surfaces.

Self-vibration cancellation of a novel bi-directional magnetized NdFeB/magnetostrictive/piezoelectric laminate

NASA Astrophysics Data System (ADS)

Leung, Chung Ming; Wang, Feifei; Wang, Ya

2016-06-01

A novel magnetoelectric (ME) laminated composite structure is proposed in this work, aiming to provide a good self-vibration cancellation performance under the magnetic field detection environment. The proposed structure consists of two Terfenol-D magnetostrictive alloy plates which are revised and length-magnetized by two NdFeB magnets bonded on the top surface of a thickness-polarized Pb(Zr, Ti)O3 (PZT) ceramic plate with separate electrodes. Experiments have shown that great vibration suppression up to 44 dB under harmonic disturbance was observed. The ME coefficient of the proposed structure also reaches up to ˜29 mV/Oe at non-resonance frequency and 758 mV/Oe at resonance frequency of 79 kHz which is ˜2 times larger than the traditional L-T Terfenol-D/PZT bilayer configuration of the same scale. Such performance improvement is achieved based on the bi-directional magnetic field bias (HBias) of two NdFeB magnets in magnetostrictive layer, internal in-series electrical wire connection in piezoelectric layer. The proposed design has great potential to be used for industrial applications associated with heavy environmental vibration noise.

High performance of mixed halide perovskite solar cells: Role of halogen atom and plasmonic nanoparticles on the ideal current density of cell

NASA Astrophysics Data System (ADS)

Mohebpour, Mohammad Ali; Saffari, Mohaddeseh; Soleimani, Hamid Rahimpour; Tagani, Meysam Bagheri

2018-03-01

To be able to increase the efficiency of perovskite solar cells which is one of the most substantial challenges ahead in photovoltaic industry, the structural and optical properties of perovskite CH3NH3PbI3-xBrx for values x = 1-3 have been studied employing density functional theory (DFT). Using the optical constants extracted from DFT calculations, the amount of light reflectance and ideal current density of a simulated single-junction perovskite solar cell have been investigated. The results of DFT calculations indicate that adding halogen bromide to CH3NH3PbI3 compound causes the relocation of energy bands in band structure which its consequence is increasing the bandgap. In addition, the effect of increasing Br in this structure can be seen as a reduction in lattice constant, refractive index, extinction and absorption coefficient. As well, results of the simulation suggest a significant current density enhancement as much as 22% can be achieved by an optimized array of Platinum nanoparticles that is remarkable. This plan is able to be a prelude for accomplishment of solar cells with higher energy conversion efficiency.

Neural network modeling of conditions of destruction of wood plank based on measurements

NASA Astrophysics Data System (ADS)

Filkin, V.; Kaverzneva, T.; Lazovskaya, T.; Lukinskiy, E.; Petrov, A.; Stolyarov, O.; Tarkhov, D.

2016-11-01

The paper deals with the possibility of predicting the ultimate load breaking timber sample based on the loading force dependence on the deflection before destruction. Prediction of mechanical properties of wood is handicapped by complex anisotropic structures. The anisotropic nature of the material and, in a great measure, the random nature of wood grain local features defining moment of destruction lead to a significant dependence of the required load on the individual characteristics of a particular bar. The ultimate load is sought as a function of the coefficients of the neural network approximation of the loading force dependence on the deflection. For this purpose, a number of experiments on timber sample loading until the destruction is conducted. Modeling of the conditions of material destruction may provide the required safety control in building industry.

Sound absorption with green materials

NASA Astrophysics Data System (ADS)

Trematerra, Amelia; Lombardi, Ilaria

2017-07-01

Green materials are a valid alternative to traditional materials that are by-products of processing oil. At the end of their useful life, green materials can be disposed of without polluting the environment. They are now being used in the construction and automotive industries. While, studies are currently being carried out in the aviation sector on the use of green materials for non-structural components of airplanes. Green materials can be used to improve the acoustic comfort inside buildings as well as mitigate reverberation, echoes effects and reduce the transmission of noise between rooms. In this paper, the acoustic measurements of the properties of green materials are reported. The absorption coefficient of samples of the materials were measured in the frequency range from 200 Hz to 2,000 Hz with an impedance tube, with the flow resistance being measured.

Approximation of effective moisture-diffusion coefficient to characterize performance of a barrier coating

NASA Astrophysics Data System (ADS)

Nagai, Shingo

2013-11-01

We report estimation of the effective diffusion coefficient of moisture through a barrier coating to develop an encapsulation technology for the thin-film electronics industry. This investigation targeted a silicon oxide (SiOx) film that was deposited on a plastic substrate by a large-process-area web coater. Using the finite difference method based on diffusion theory, our estimation of the effective diffusion coefficient of a SiOx film corresponded to that of bulk glass that was previously reported. This result suggested that the low diffusivities of barrier films can be obtained on a mass-production level in the factory. In this investigation, experimental observations and mathematical confirmation revealed the limit of the water vapor transmission rate on the single barrier coating.

Operando XRD studies as a tool for determination of transport parameters of mobile ions in electrode materials

NASA Astrophysics Data System (ADS)

Kondracki, Łukasz; Kulka, Andrzej; Świerczek, Konrad; Ziąbka, Magdalena; Molenda, Janina

2017-11-01

In this work a detailed operando XRD investigations of structural properties of LixMn2O4 manganese spinel are shown to be a complementary, successful method of determination of diffusion coefficient D and surface exchange coefficient k in the working electrode. Kinetics of lithium ions transport are estimated on the basis of rate of structural changes of the cathode material during a relaxation stage after a high current charge, i.e. during structural relaxation of the material. The presented approach seems to be applicable as a complementary method of determination of transport coefficients for all intercalation-type electrode materials.

Lattice-structures and constructs with designed thermal expansion coefficients

DOEpatents

Spadaccini, Christopher; Hopkins, Jonathan

2014-10-28

A thermal expansion-managed lattice structure having a plurality of unit cells each having flexure bearing-mounted tabs supported on a base and actuated by thermal expansion of an actuator having a thermal expansion coefficient greater than the base and arranged so that the tab is inwardly displaced into a base cavity. The flexure bearing-mounted tabs are connected to other flexure-bearing-mounted tabs of adjacent unit cells so that the adjacent unit cells are spaced from each other to accommodate thermal expansion of individual unit cells while maintaining a desired bulk thermal expansion coefficient of the lattice structure as a whole.

Research and Development of Methods for Estimating Physicochemical Properties of Organic Compounds of Environmental Concern

DTIC Science & Technology

1979-02-01

coefficient (at equilibrium) when hysteresis is apparent. 6. Coefficient n in Freundlich equation for 1/n soil or sediment adsorption isotherms ýX - KC . 7...Biodegradation Chemical structures cal clasaes (e.g., Diffusion Correlations phenols). General Diffusion coefficients Equations terms for organic...OF THE FATE AND TRANSPORT OF ORGANIC CHEMICALS Adsorption coefficients: K, n* from Freundlich equation + Desorption coefficients: K’*, n’* from

Investigation of coherent structures in a superheated jet using decomposition methods

NASA Astrophysics Data System (ADS)

Sinha, Avick; Gopalakrishnan, Shivasubramanian; Balasubramanian, Sridhar

2016-11-01

A superheated turbulent jet, commonly encountered in many engineering flows, is complex two phase mixture of liquid and vapor. The superposition of temporally and spatially evolving coherent vortical motions, known as coherent structures (CS), govern the dynamics of such a jet. Both POD and DMD are employed to analyze such vortical motions. PIV data is used in conjunction with the decomposition methods to analyze the CS in the flow. The experiments were conducted using water emanating into a tank containing homogeneous fluid at ambient condition. Three inlet pressure were employed in the study, all at a fixed inlet temperature. 90% of the total kinetic energy in the mean flow is contained within the first five modes. The scatterplot for any two POD coefficients predominantly showed a circular distribution, representing a strong connection between the two modes. We speculate that the velocity and vorticity contours of spatial POD basis functions show presence of K-H instability in the flow. From DMD, eigenvalues away from the origin is observed for all the cases indicating the presence of a non-oscillatory structure. Spatial structures are also obtained from DMD. The authors are grateful to Confederation of Indian Industry and General Electric India Pvt. Ltd. for partial funding of this project.

A novel Mo-W interlayer approach for CVD diamond deposition on steel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kundrát, Vojtěch; Sullivan, John; Ye, Haitao, E-mail: h.ye@aston.ac.uk

Steel is the most widely used material in engineering for its cost/performance ratio and coatings are routinely applied on its surface to further improve its properties. Diamond coated steel parts are an option for many demanding industrial applications through prolonging the lifetime of steel parts, enhancement of tool performance as well as the reduction of wear rates. Direct deposition of diamond on steel using conventional chemical vapour deposition (CVD) processes is known to give poor results due to the preferential formation of amorphous carbon on iron, nickel and other elements as well as stresses induced from the significant difference inmore » the thermal expansion coefficients of those materials. This article reports a novel approach of deposition of nanocrystalline diamond coatings on high-speed steel (M42) substrates using a multi-structured molybdenum (Mo) – tungsten (W) interlayer to form steel/Mo/Mo-W/W/diamond sandwich structures which overcome the adhesion problem related to direct magnetron sputtering deposition of pure tungsten. Surface, interface and tribology properties were evaluated to understand the role of such an interlayer structure. The multi-structured Mo-W interlayer has been proven to improve the adhesion between diamond films and steel substrates by acting as an effective diffusion barrier during the CVD diamond deposition.« less

A novel Mo-W interlayer approach for CVD diamond deposition on steel

NASA Astrophysics Data System (ADS)

Kundrát, Vojtěch; Zhang, Xiaoling; Cooke, Kevin; Sun, Hailin; Sullivan, John; Ye, Haitao

2015-04-01

Steel is the most widely used material in engineering for its cost/performance ratio and coatings are routinely applied on its surface to further improve its properties. Diamond coated steel parts are an option for many demanding industrial applications through prolonging the lifetime of steel parts, enhancement of tool performance as well as the reduction of wear rates. Direct deposition of diamond on steel using conventional chemical vapour deposition (CVD) processes is known to give poor results due to the preferential formation of amorphous carbon on iron, nickel and other elements as well as stresses induced from the significant difference in the thermal expansion coefficients of those materials. This article reports a novel approach of deposition of nanocrystalline diamond coatings on high-speed steel (M42) substrates using a multi-structured molybdenum (Mo) - tungsten (W) interlayer to form steel/Mo/Mo-W/W/diamond sandwich structures which overcome the adhesion problem related to direct magnetron sputtering deposition of pure tungsten. Surface, interface and tribology properties were evaluated to understand the role of such an interlayer structure. The multi-structured Mo-W interlayer has been proven to improve the adhesion between diamond films and steel substrates by acting as an effective diffusion barrier during the CVD diamond deposition.

Revealing how network structure affects accuracy of link prediction

NASA Astrophysics Data System (ADS)

Yang, Jin-Xuan; Zhang, Xiao-Dong

2017-08-01

Link prediction plays an important role in network reconstruction and network evolution. The network structure affects the accuracy of link prediction, which is an interesting problem. In this paper we use common neighbors and the Gini coefficient to reveal the relation between them, which can provide a good reference for the choice of a suitable link prediction algorithm according to the network structure. Moreover, the statistical analysis reveals correlation between the common neighbors index, Gini coefficient index and other indices to describe the network structure, such as Laplacian eigenvalues, clustering coefficient, degree heterogeneity, and assortativity of network. Furthermore, a new method to predict missing links is proposed. The experimental results show that the proposed algorithm yields better prediction accuracy and robustness to the network structure than existing currently used methods for a variety of real-world networks.

Warming of Monolithic Structures in Winter

NASA Astrophysics Data System (ADS)

Pikus, G. A.; Lebed, A. R.

2017-11-01

The present work attempts to develop a mathematical model for calculating the heat transfer coefficient of the fence of monolithic structures erected in winter. The urgency and, at the same time, the practical significance of the research lies in the fact that to date no simple, effective tool has been developed to ensure the elimination of the unfavorable thermally stressed state of a structure’s concrete from maximum equalization of temperatures across its cross-section. The main problem for concrete is a high temperature which leads to a sharp decrease in the quality of erected structures due to developing cracks. This paper based on the well-known Newton’s law and its differential equation demonstrates the formula of concrete cooling and the analysis of its proportionality coefficient. Based on the literature analysis, it is established that the proportionality coefficient is determined by the thermophysical properties of concrete, the size and shape of the structure, and the intensity of its heat exchange with the surrounding medium. A limitation was used on the temperature gradient over the section of the monolithic structure to derive a formula for calculating the reduced heat transfer coefficient of a concrete fence. All mathematical calculations are given for cooling monolithic constructions in the form of plates. At the end of the work an example is given for the calculation of the required reduced heat transfer coefficient for the fence ensuring compliance with the permissible concrete temperature gradient.

Measuring the Electro-Optic Coefficients of Bulk-poled Polymers

DTIC Science & Technology

2012-09-01

polymethylmethacrylate (PMMA) was produced by CYRO Industries (Acrylite H15) and distributed by AMCO Plastics. All other chemicals were obtained from Sigma...nitrostyryl) benzene) PMMA polymethylmethacrylate RMS root-mean-square ROMP ring-opening metathesis polymer Tg glass transition temperature

Commercializing potassium terbium fluoride, KTF (KTb3F10) faraday crystals for high laser power optical isolator applications

NASA Astrophysics Data System (ADS)

Schlichting, Wolfgang; Stevens, Kevin; Foundos, Greg; Payne, Alexis

2017-10-01

Many scientific lasers and increasingly industrial laser systems operate in <500W and kW output power regime, require high-performance optical isolators to prevent disruptive light feedback into the laser cavity. The optically active Faraday material is the key optical element inside the isolator. SYNOPTICS has been supplying the laser market with Terbium Gallium Garnet (TGG - Tb3Ga5O12) for many years. It is the most commonly used material for the 650-1100nm range and the key advantages for TGG include its cubic crystal structure for alignment free processing, little to no intrinsic birefringence, and ease of manufacture. However, for high-power laser applications TGG is limited by its absorption at 1064nm and its thermo-optic coefficient, dn/dT. Specifically, thermal lensing and depolarization effects become a limiting factor at high laser powers. While TGG absorption has improved significantly over the past few years, there is an intrinsic limit. Now, SYNOPTICS is commercializing the enhanced new crystal Potassium Terbium Fluoride KTF (KTb3F10) that exhibits much smaller nonlinear refractive index and thermo-optic coefficients, and still exhibits a Verdet constant near that of TGG. This cubic crystal has relatively low absorption and thermo-optic coefficients. It is now fully characterized and available for select production orders. At OPTIFAB in October 2017 we present recent results comparing the performance of KTF to TGG in optical isolators and show SYNOPTICS advances in large volume crystal growth and the production ramp up.

40 CFR Table 1 to Subpart G of... - Process Vents-Coefficients for Total Resource Effectiveness for Existing Source Nonhalogenated...

Code of Federal Regulations, 2013 CFR

2013-07-01

... Coefficients a b c d Nonhalogenated Flare 1.935 3.660×10−1 −7.687×10−3 −7.333×10−4 Thermal Incinerator 0... Standards for Organic Hazardous Air Pollutants From the Synthetic Organic Chemical Manufacturing Industry... 2.519 1.183×10−2 1.300×10−2 4.790×10−2 Halogenated Thermal Incinerator and Scrubber 3.995 5.200×10−2...

40 CFR Table 1 to Subpart G of... - Process Vents-Coefficients for Total Resource Effectiveness for Existing Source Nonhalogenated...

Code of Federal Regulations, 2012 CFR

2012-07-01

... Coefficients a b c d Nonhalogenated Flare 1.935 3.660×10−1 −7.687×10−3 −7.333×10−4 Thermal Incinerator 0... Standards for Organic Hazardous Air Pollutants From the Synthetic Organic Chemical Manufacturing Industry... 2.519 1.183×10−2 1.300×10−2 4.790×10−2 Halogenated Thermal Incinerator and Scrubber 3.995 5.200×10−2...

40 CFR Table 1 to Subpart G of... - Process Vents-Coefficients for Total Resource Effectiveness for Existing Source Nonhalogenated...

Code of Federal Regulations, 2014 CFR

2014-07-01

... Coefficients a b c d Nonhalogenated Flare 1.935 3.660×10−1 −7.687×10−3 −7.333×10−4 Thermal Incinerator 0... Standards for Organic Hazardous Air Pollutants From the Synthetic Organic Chemical Manufacturing Industry... 2.519 1.183×10−2 1.300×10−2 4.790×10−2 Halogenated Thermal Incinerator and Scrubber 3.995 5.200×10−2...

40 CFR Table 1 to Subpart G of... - Process Vents-Coefficients for Total Resource Effectiveness for Existing Source Nonhalogenated...

Code of Federal Regulations, 2010 CFR

2010-07-01

... Coefficients a b c d Nonhalogenated Flare 1.935 3.660×10−1 −7.687×10−3 −7.333×10−4 Thermal Incinerator 0... Standards for Organic Hazardous Air Pollutants From the Synthetic Organic Chemical Manufacturing Industry... 2.519 1.183×10−2 1.300×10−2 4.790×10−2 Halogenated Thermal Incinerator and Scrubber 3.995 5.200×10−2...

Predictive ecotoxicity of MoA 1 of organic chemicals using in silico approaches.

PubMed

de Morais E Silva, Luana; Alves, Mateus Feitosa; Scotti, Luciana; Lopes, Wilton Silva; Scotti, Marcus Tullius

2018-05-30

Persistent organic products are compounds used for various purposes, such as personal care products, surfactants, colorants, industrial additives, food, pesticides and pharmaceuticals. These substances are constantly introduced into the environment and many of these pollutants are difficult to degrade. Toxic compounds classified as MoA 1 (Mode of Action 1) are low toxicity compounds that comprise nonreactive chemicals. In silico methods such as Quantitative Structure-Activity Relationships (QSARs) have been used to develop important models for prediction in several areas of science, as well as aquatic toxicity studies. The aim of the present study was to build a QSAR model-based set of theoretical Volsurf molecular descriptors using the fish acute toxicity values of compounds defined as MoA 1 to identify the molecular properties related to this mechanism. The selected Partial Least Squares (PLS) results based on the values of cross-validation coefficients of determination (Q cv 2 ) show the following values: Q cv 2 = 0.793, coefficient of determination (R 2 ) = 0.823, explained variance in external prediction (Q ext 2 ) = 0.87. From the selected descriptors, not only the hydrophobicity is related to the toxicity as already mentioned in previously published studies but other physicochemical properties combined contribute to the activity of these compounds. The symmetric distribution of the hydrophobic moieties in the structure of the compounds as well as the shape, as branched chains, are important features that are related to the toxicity. This information from the model can be useful in predicting so as to minimize the toxicity of organic compounds. Copyright © 2018. Published by Elsevier Inc.

The effect of electron-beam irradiation and halogen-free flame retardants on properties of poly butylene terephthalate

NASA Astrophysics Data System (ADS)

Hooshangi, Zhila; Feghhi, Seyed Amir Hossein; Sheikh, Nasrin

2015-03-01

Engineering plastics like Poly (butylene terephthalate) due to their desirable properties have various industrial applications. Neat PBT is highly combustible, so it is necessary to improve significantly its fire retardancy to meet the fire safety requirements. The combustion performance of PBT can be improved by addition of appropriate flame retardant additives. In this study we have investigated the effect of halogen free flame retardants, i.e. melamine and aluminum phosphate, and instantaneously electron beam radiation-induced crosslinking in the presence of Triallyl cyanurate on various properties of PBT. The results of gel content showed that a dose range of 200-400 kGy leads to high cross linked structure in this polymer. Also mechanical experiments showed that its structure became rigid and fragile due to irradiation. Radiation crosslinking of this polymer made its dielectric loss coefficient ten times lower than non-irradiated polymer, but had no effect on its dielectric constant. Moreover the addition of the fire retardant additives as impurity decreased the dielectric loss coefficient. TGA analysis in nitrogen exhibited that irradiation increases char formation and use of the fire retardant additives leads to reduction of onset temperature and formation of higher char quantity than pure PBT. According to the results of UL-94, irradiated samples burned with lower speed and less dripping in vertical and horizontal positions than pure polymer. Finally irradiation of the polymers containing fire retardant additives with a dose of 400 kGy led to self-extinguishing and non-dripping and reach to V-0 level in the UL-94 V.

Electric Power Consumption Coefficients for U.S. Industries: Regional Estimation and Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Boero, Riccardo

Economic activity relies on electric power provided by electrical generation, transmission, and distribution systems. This paper presents a method developed at Los Alamos National Laboratory to estimate electric power consumption by different industries in the United States. Results are validated through comparisons with existing literature and benchmarking data sources. We also discuss the limitations and applications of the presented method, such as estimating indirect electric power consumption and assessing the economic impact of power outages based on input-output economic models.

A Variable Input-Output Model for Inflation, Growth, and Energy for the Korean Economy.

DTIC Science & Technology

1983-12-01

and the sales price of cukput as determinan -s of the technical coefficients were suggested by Walras [Ref. 4] and many other eco.cmis.s. (Ref. 5] Arrow...34included in manufacturing and construction secter. The other industries include the social and government services. 32 Ii. * 1.’ *. - .-- :~ ~~\\ ~~ v...e3lectricity, government enterprise, and other social commercial industries. The rate of growth of the money suiply and interest ratqs on loans are the key

PREDICTION OF THE SOLUBILITY, ACTIVITY COEFFICIENT AND LIQUID/LIQUID PARTITION COEFFICIENT OF ORGANIC COMPOUNDS

EPA Science Inventory

Solvation models, based on fundamental chemical structure theory, were developed in the SPARC mechanistic tool box to predict a large array of physical properties of organic compounds in water and in non-aqueous solvents strictly from molecular structure. The SPARC self-interact...

A view on thermodynamics of concentrated electrolytes: Modification necessity for electrostatic contribution of osmotic coefficient

NASA Astrophysics Data System (ADS)

Sahu, Jyoti; Juvekar, Vinay A.

2018-05-01

Prediction of the osmotic coefficient of concentrated electrolytes is needed in a wide variety of industrial applications. There is a need to correctly segregate the electrostatic contribution to osmotic coefficient from nonelectrostatic contribution. This is achieved in a rational way in this work. Using the Robinson-Stokes-Glueckauf hydrated ion model to predict non-electrostatic contribution to the osmotic coefficient, it is shown that hydration number should be independent of concentration so that the observed linear dependence of osmotic coefficient on electrolyte concentration in high concentration range could be predicted. The hydration number of several electrolytes (LiCl, NaCl, KCl, MgCl2, and MgSO4) has been estimated by this method. The hydration number predicted by this model shows correct dependence on temperature. It is also shown that the electrostatic contribution to osmotic coefficient is underpredicted by the Debye-Hückel theory at concentration beyond 0.1 m. The Debye-Hückel theory is modified by introducing a concentration dependent hydrated ionic size. Using the present analysis, it is possible to correctly estimate the electrostatic contribution to the osmotic coefficient, beyond the range of validation of the D-H theory. This would allow development of a more fundamental model for electrostatic interaction at high electrolyte concentrations.

The theoretical ultimate magnetoelectric coefficients of magnetoelectric composites by optimization design

NASA Astrophysics Data System (ADS)

Wang, H.-L.; Liu, B.

2014-03-01

This paper investigates what is the largest magnetoelectric (ME) coefficient of ME composites, and how to realize it. From the standpoint of energy conservation, a theoretical analysis is carried out on an imaginary lever structure consisting of a magnetostrictive phase, a piezoelectric phase, and a rigid lever. This structure is a generalization of various composite layouts for optimization on ME effect. The predicted theoretical ultimate ME coefficient plays a similar role as the efficiency of ideal heat engine in thermodynamics, and is used to evaluate the existing typical ME layouts, such as the parallel sandwiched layout and the serial layout. These two typical layouts exhibit ME coefficient much lower than the theoretical largest values, because in the general analysis the stress amplification ratio and the volume ratio can be optimized independently and freely, but in typical layouts they are dependent or fixed. To overcome this shortcoming and achieve the theoretical largest ME coefficient, a new design is presented. In addition, it is found that the most commonly used electric field ME coefficient can be designed to be infinitely large. We doubt the validity of this coefficient as a reasonable ME effect index and consider three more ME coefficients, namely the electric charge ME coefficient, the voltage ME coefficient, and the static electric energy ME coefficient. We note that the theoretical ultimate value of the static electric energy ME coefficient is finite and might be a more proper measure of ME effect.

The theoretical ultimate magnetoelectric coefficients of magnetoelectric composites by optimization design

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, H.-L.; Liu, B., E-mail: liubin@tsinghua.edu.cn

2014-03-21

This paper investigates what is the largest magnetoelectric (ME) coefficient of ME composites, and how to realize it. From the standpoint of energy conservation, a theoretical analysis is carried out on an imaginary lever structure consisting of a magnetostrictive phase, a piezoelectric phase, and a rigid lever. This structure is a generalization of various composite layouts for optimization on ME effect. The predicted theoretical ultimate ME coefficient plays a similar role as the efficiency of ideal heat engine in thermodynamics, and is used to evaluate the existing typical ME layouts, such as the parallel sandwiched layout and the serial layout.more » These two typical layouts exhibit ME coefficient much lower than the theoretical largest values, because in the general analysis the stress amplification ratio and the volume ratio can be optimized independently and freely, but in typical layouts they are dependent or fixed. To overcome this shortcoming and achieve the theoretical largest ME coefficient, a new design is presented. In addition, it is found that the most commonly used electric field ME coefficient can be designed to be infinitely large. We doubt the validity of this coefficient as a reasonable ME effect index and consider three more ME coefficients, namely the electric charge ME coefficient, the voltage ME coefficient, and the static electric energy ME coefficient. We note that the theoretical ultimate value of the static electric energy ME coefficient is finite and might be a more proper measure of ME effect.« less

Experimental investigation of heat transfer characteristics of guar-based polymer solutions and gels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Azouz, I.; Vinod, P.S.; Shah, S.N.

1996-12-31

An experimental investigation of the heat transfer characteristics of hydraulic fracturing fluids was conducted at the Fracturing Fluid Characterization Facility (FFCF) of the University of Oklahoma. The facility is equipped with a high pressure fracture simulator, coiled tubing fluid pre-conditioning system, and a full-scale, counter-current, double pipe heat exchanger. The fluids investigated include non-crosslinked and borate-crosslinked guar gum and hydroxypropyl guar (HPG). Results were also obtained for water and were used as a basis for comparison. The effects of flow rate, operating temperature, pH, and various levels of shear pre-conditioning, on the heat transfer behavior of the test fluids weremore » investigated. Results show a significant difference between the heat transfer coefficient of the pure solvent (water) and those of the polymer solutions tested. While all polymer solutions tested exhibited lower heat transfer coefficients than that of the pure solvent, crosslinking appears to enhance the heat transfer characteristics of the polymer fluids. It was also observed that shear preconditioning does not seem to have a significant effect on the heat transfer coefficient of the crosslinked gels. These findings are of great interest to the industry, especially to the petroleum industry where these fluids are commonly used during hydraulic fracturing of hydrocarbon reservoirs.« less

Advertising Agencies: An Analysis of Industry Structure.

ERIC Educational Resources Information Center

Smith, Sandra J.

Noting that advertising agencies have not been examined as a collective industry, this paper looks at the development and structure of the advertising agency industry. The first portion of the paper discusses the development of the agency. The remaining two sections deal with trends in and the structure of the industry including: (1) the growth of…

Sensitivity study on durability variables of marine concrete structures

NASA Astrophysics Data System (ADS)

Zhou, Xin'gang; Li, Kefei

2013-06-01

In order to study the influence of parameters on durability of marine concrete structures, the parameter's sensitivity analysis was studied in this paper. With the Fick's 2nd law of diffusion and the deterministic sensitivity analysis method (DSA), the sensitivity factors of apparent surface chloride content, apparent chloride diffusion coefficient and its time dependent attenuation factor were analyzed. The results of the analysis show that the impact of design variables on concrete durability was different. The values of sensitivity factor of chloride diffusion coefficient and its time dependent attenuation factor were higher than others. Relative less error in chloride diffusion coefficient and its time dependent attenuation coefficient induces a bigger error in concrete durability design and life prediction. According to probability sensitivity analysis (PSA), the influence of mean value and variance of concrete durability design variables on the durability failure probability was studied. The results of the study provide quantitative measures of the importance of concrete durability design and life prediction variables. It was concluded that the chloride diffusion coefficient and its time dependent attenuation factor have more influence on the reliability of marine concrete structural durability. In durability design and life prediction of marine concrete structures, it was very important to reduce the measure and statistic error of durability design variables.

Theoretical studies on a TeO2/ZnO/diamond-layered structure for zero TCD SAW devices

NASA Astrophysics Data System (ADS)

Dewan, Namrata; Sreenivas, K.; Gupta, Vinay

2008-08-01

High-frequency surface acoustic wave (SAW) devices based on diamond substrate are useful because of their very high SAW velocity. In the present work, SAW propagation characteristics, such as phase velocity, coupling coefficient and temperature coefficient of delay (TCD) of a TeO2/ZnO/diamond-layered structure, are examined using theoretical calculations. The ZnO/diamond bi-layer structure is found to exhibit a high positive TCD value. A zero TCD device structure is obtained after integration with a TeO2 over layer having a negative TCD value. Introduction of a non-piezoelectric TeO2 over layer on the bi-layer structure (ZnO/diamond) increases the coupling coefficient. A relatively low thickness of TeO2 thin film (~(1.6-3.1) × 10-3λ) is required to achieve temperature-stable SAW devices based on diamond.

Predicting cyclohexane/water distribution coefficients for the SAMPL5 challenge using MOSCED and the SMD solvation model.

PubMed

Diaz-Rodriguez, Sebastian; Bozada, Samantha M; Phifer, Jeremy R; Paluch, Andrew S

2016-11-01

We present blind predictions using the solubility parameter based method MOSCED submitted for the SAMPL5 challenge on calculating cyclohexane/water distribution coefficients at 298 K. Reference data to parameterize MOSCED was generated with knowledge only of chemical structure by performing solvation free energy calculations using electronic structure calculations in the SMD continuum solvent. To maintain simplicity and use only a single method, we approximate the distribution coefficient with the partition coefficient of the neutral species. Over the final SAMPL5 set of 53 compounds, we achieved an average unsigned error of [Formula: see text] log units (ranking 15 out of 62 entries), the correlation coefficient (R) was [Formula: see text] (ranking 35), and [Formula: see text] of the predictions had the correct sign (ranking 30). While used here to predict cyclohexane/water distribution coefficients at 298 K, MOSCED is broadly applicable, allowing one to predict temperature dependent infinite dilution activity coefficients in any solvent for which parameters exist, and provides a means by which an excess Gibbs free energy model may be parameterized to predict composition dependent phase-equilibrium.

Results from Radio Tracking the Rosetta Spacecraft: Gravity, Internal Structure and Nucleus Composition of 67P/Churyumov-Gerasimenko

NASA Astrophysics Data System (ADS)

Hahn, M.; Andert, T.; Asmar, S.; Bird, M. K.; Häusler, B.; Peter, K.; Tellmann, S.; Weissman, P. R.; Barriot, J. P.; Sierks, H.

2017-12-01

When Rosetta arrived at its target comet 67P/Churyumov-Gerasimenko it first performed a series of distant flybys (100 - 30 km). During this mission phase the mass of the comets nucleus could be determined by analyzing the RSI radio tracking data. In combination with the volume from images of the OSIRIS camera this resulted in a precise bulk density determination. That already gave first insights into the comets interior structure. The nucleus appears to be a low-density, highly porous dusty body. From bound orbits with distances below 30 km the low degree and order gravity field coefficients could be derived. The gravity field coefficients strongly depend on the nucleus irregular shape and on the interior mass distribution. The shape is very well reconstructed from of the OSIRIS camera images. Various models of the interior nucleus structure and density distributions are used to compute simulated values of the gravity field coefficients. A comparison with the observed coefficients yields the feasibility of the theoretical interior structure. Thus, the gravity field helps constraining models of the internal structure, the composition and also of the origin and formation of the comets nucleus.

Classification of damage in structural systems using time series analysis and supervised and unsupervised pattern recognition techniques

NASA Astrophysics Data System (ADS)

Omenzetter, Piotr; de Lautour, Oliver R.

2010-04-01

Developed for studying long, periodic records of various measured quantities, time series analysis methods are inherently suited and offer interesting possibilities for Structural Health Monitoring (SHM) applications. However, their use in SHM can still be regarded as an emerging application and deserves more studies. In this research, Autoregressive (AR) models were used to fit experimental acceleration time histories from two experimental structural systems, a 3- storey bookshelf-type laboratory structure and the ASCE Phase II SHM Benchmark Structure, in healthy and several damaged states. The coefficients of the AR models were chosen as damage sensitive features. Preliminary visual inspection of the large, multidimensional sets of AR coefficients to check the presence of clusters corresponding to different damage severities was achieved using Sammon mapping - an efficient nonlinear data compression technique. Systematic classification of damage into states based on the analysis of the AR coefficients was achieved using two supervised classification techniques: Nearest Neighbor Classification (NNC) and Learning Vector Quantization (LVQ), and one unsupervised technique: Self-organizing Maps (SOM). This paper discusses the performance of AR coefficients as damage sensitive features and compares the efficiency of the three classification techniques using experimental data.

Precision Composite Space Structures

DTIC Science & Technology

2007-10-15

large structures. 15. SUBJECT TERMS Composite materials, dimensional stability, microcracking, thermal expansion , space structures, degradation...Figure 32. Variation of normalized coefficients of thermal expansion α11(n), α22(n), and α33(n) with normalized crack density of an AS4/3501-6...coefficients of thermal expansion α11(n), α22(n), and α33(n) with normalized crack density of an AS4/3501-6 composite lamina with a fiber volume

Structured light imaging system for structural and optical characterization of 3D tissue-simulating phantoms

NASA Astrophysics Data System (ADS)

Liu, Songde; Smith, Zach; Xu, Ronald X.

2016-10-01

There is a pressing need for a phantom standard to calibrate medical optical devices. However, 3D printing of tissue-simulating phantom standard is challenged by lacking of appropriate methods to characterize and reproduce surface topography and optical properties accurately. We have developed a structured light imaging system to characterize surface topography and optical properties (absorption coefficient and reduced scattering coefficient) of 3D tissue-simulating phantoms. The system consisted of a hyperspectral light source, a digital light projector (DLP), a CMOS camera, two polarizers, a rotational stage, a translation stage, a motion controller, and a personal computer. Tissue-simulating phantoms with different structural and optical properties were characterized by the proposed imaging system and validated by a standard integrating sphere system. The experimental results showed that the proposed system was able to achieve pixel-level optical properties with a percentage error of less than 11% for absorption coefficient and less than 7% for reduced scattering coefficient for phantoms without surface curvature. In the meanwhile, 3D topographic profile of the phantom can be effectively reconstructed with an accuracy of less than 1% deviation error. Our study demonstrated that the proposed structured light imaging system has the potential to characterize structural profile and optical properties of 3D tissue-simulating phantoms.

Thermophysical properties and rheological behavior of electro-rheological fluids at different temperatures

NASA Astrophysics Data System (ADS)

Korobko, Evguenia V.; Korobko, Yulia O.

2000-04-01

Fluid disperse systems, sensitive to the external electric field-electrorheological fluids, are finding increasing use in various areas of industry and technology. Their physicomechanical, electrophysical characteristics determine the valuable specific properties of the materials with assigned structure, obtainable with everwide use of electric fields, which makes it possible to substantially enhance efficiency and productiveness of technological processes and to improve the control of operational regimes of the equipment which employ fluid disperse media. The present investigations has been undertaken with the aim of studying thermophysical properties and rheophysical behavior of low-concentration ER- fluid (diatomite in transformer oil) at different temperatures. It was shown that the electric field, which changes considerably the structure of electrorheological fluid, influences effective thermal conductivity and diffusivity coefficients. Their increase with electric field intensity and the increase of the effective viscosity with temperature are connected with the increase of the conductive component of the overall heat transfer through the contact spots between the solid particles, and with intensification of electric convection in the spaces between the dispersed particles.

Graph characterization via Ihara coefficients.

PubMed

Ren, Peng; Wilson, Richard C; Hancock, Edwin R

2011-02-01

The novel contributions of this paper are twofold. First, we demonstrate how to characterize unweighted graphs in a permutation-invariant manner using the polynomial coefficients from the Ihara zeta function, i.e., the Ihara coefficients. Second, we generalize the definition of the Ihara coefficients to edge-weighted graphs. For an unweighted graph, the Ihara zeta function is the reciprocal of a quasi characteristic polynomial of the adjacency matrix of the associated oriented line graph. Since the Ihara zeta function has poles that give rise to infinities, the most convenient numerically stable representation is to work with the coefficients of the quasi characteristic polynomial. Moreover, the polynomial coefficients are invariant to vertex order permutations and also convey information concerning the cycle structure of the graph. To generalize the representation to edge-weighted graphs, we make use of the reduced Bartholdi zeta function. We prove that the computation of the Ihara coefficients for unweighted graphs is a special case of our proposed method for unit edge weights. We also present a spectral analysis of the Ihara coefficients and indicate their advantages over other graph spectral methods. We apply the proposed graph characterization method to capturing graph-class structure and clustering graphs. Experimental results reveal that the Ihara coefficients are more effective than methods based on Laplacian spectra.

Does network topology influence systemic risk contribution? A perspective from the industry indices in Chinese stock market.

PubMed

Long, Haiming; Zhang, Ji; Tang, Nengyu

2017-01-01

This study considers the effect of an industry's network topology on its systemic risk contribution to the stock market using data from the CSI 300 two-tier industry indices from the Chinese stock market. We first measure industry's conditional-value-at-risk (CoVaR) and the systemic risk contribution (ΔCoVaR) using the fitted time-varying t-copula function. The network of the stock industry is established based on dynamic conditional correlations with the minimum spanning tree. Then, we investigate the connection characteristics and topology of the network. Finally, we utilize seemingly unrelated regression estimation (SUR) of panel data to analyze the relationship between network topology of the stock industry and the industry's systemic risk contribution. The results show that the systemic risk contribution of small-scale industries such as real estate, food and beverage, software services, and durable goods and clothing, is higher than that of large-scale industries, such as banking, insurance and energy. Industries with large betweenness centrality, closeness centrality, and clustering coefficient and small node occupancy layer are associated with greater systemic risk contribution. In addition, further analysis using a threshold model confirms that the results are robust.

Influence of hydrostatic pressure on the built-in electric field in ZnO/ZnMgO quantum wells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Teisseyre, Henryk, E-mail: teiss@ifpan.edu.pl; Institute of High Pressure, Polish Academy of Sciences, Sokołowska 29/37, 01-142 Warsaw; Kaminska, Agata

We used high hydrostatic pressure to perform photoluminescence measurements on polar ZnO/ZnMgO quantum well structures. Our structure oriented along the c-direction (polar direction) was grown by plasma-assisted molecular beam epitaxy on a-plane sapphire. Due to the intrinsic electric field, which exists in polar wurtzite structure at ambient pressure, we observed a red shift of the emission related to the quantum-confined Stark effect. In the high hydrostatic pressure experiment, we observed a strong decrease of the quantum well pressure coefficients with increased thickness of the quantum wells. Generally, a narrower quantum well gave a higher pressure coefficient, closer to the band-gapmore » pressure coefficient of bulk material 20 meV/GPa for ZnO, while for wider quantum wells it is much lower. We observed a pressure coefficient of 19.4 meV/GPa for a 1.5 nm quantum well, while for an 8 nm quantum well the pressure coefficient was equal to 8.9 meV/GPa only. This is explained by taking into account the pressure-induced increase of the strain in our structure. The strain was calculated taking in to account that in-plane strain is not equal (due to fact that we used a-plane sapphire as a substrate) and the potential distribution in the structure was calculated self-consistently. The pressure induced increase of the built-in electric field is the same for all thicknesses of quantum wells, but becomes more pronounced for thicker quantum wells due to the quantum confined Stark effect lowering the pressure coefficients.« less

Modeling online social signed networks

NASA Astrophysics Data System (ADS)

Li, Le; Gu, Ke; Zeng, An; Fan, Ying; Di, Zengru

2018-04-01

People's online rating behavior can be modeled by user-object bipartite networks directly. However, few works have been devoted to reveal the hidden relations between users, especially from the perspective of signed networks. We analyze the signed monopartite networks projected by the signed user-object bipartite networks, finding that the networks are highly clustered with obvious community structure. Interestingly, the positive clustering coefficient is remarkably higher than the negative clustering coefficient. Then, a Signed Growing Network model (SGN) based on local preferential attachment is proposed to generate a user's signed network that has community structure and high positive clustering coefficient. Other structural properties of the modeled networks are also found to be similar to the empirical networks.

Effect of gradient dielectric coefficient in a functionally graded material (FGM) substrate on the propagation behavior of love waves in an FGM-piezoelectric layered structure.

PubMed

Cao, Xiaoshan; Shi, Junping; Jin, Feng

2012-06-01

The propagation behavior of Love waves in a layered structure that includes a functionally graded material (FGM) substrate carrying a piezoelectric thin film is investigated. Analytical solutions are obtained for both constant and gradient dielectric coefficients in the FGM substrate. Numerical results show that the gradient dielectric coefficient decreases phase velocity in any mode, and the electromechanical coupling factor significantly increases in the first- and secondorder modes. In some modes, the difference in Love waves' phase velocity between these two types of structure might be more than 1%, resulting in significant differences in frequency of the surface acoustic wave devices.

Prediction of industrial tomato hybrids from agronomic traits and ISSR molecular markers.

PubMed

Figueiredo, A S T; Resende, J T V; Faria, M V; Da-Silva, P R; Fagundes, B S; Morales, R G F

2016-05-13

Heterosis is a highly relevant phenomenon in plant breeding. This condition is usually established in hybrids derived from crosses of highly divergent parents. The success of a breeder in obtaining heterosis is directly related to the correct identification of genetically contrasting parents. Currently, the diallel cross is the most commonly used methodology to detect contrasting parents; however, it is a time- and cost-consuming procedure. Therefore, new tools capable of performing this task quickly and accurately are required. Thus, the purpose of this study was to estimate the genetic divergence in industrial tomato lines, based on agronomic traits, and to compare with estimates obtained using inter-simple sequence repeat (ISSR) molecular markers. The genetic divergence among 10 industrial tomato lines, based on nine morphological characters and 12 ISSR primers was analyzed. For data analysis, Pearson and Spearman correlation coefficients were calculated between the genetic dissimilarity measures estimated by Mahalanobis distance and Jaccard's coefficient of genetic dissimilarity from the heterosis estimates, combining ability, and means of important traits of industrial tomato. The ISSR markers efficiently detected contrasting parents for hybrid production in tomato. Parent RVTD-08 was indicated as the most divergent, both by molecular and morphological markers, that positively contributed to increased heterosis and by the specific combining ability in the crosses in which it participated. The genetic dissimilarity estimated by ISSR molecular markers aided the identification of the best hybrids of the experiment in terms of total fruit yield, pulp yield, and soluble solids content.

Ternary liquid-liquid equilibria for the phenolic compounds extraction from artificial textile industrial waste

NASA Astrophysics Data System (ADS)

Fardhyanti, Dewi Selvia; Prasetiawan, Haniif; Hermawan, Sari, Lelita Sakina

2017-03-01

Liquid waste in textile industry contains large amounts of dyes and chemicals which are capable of harming the environment and human health. It is due to liquid waste characteristics which have high BOD, COD, temperature, dissolved and suspended solid. One of chemical compound which might be harmful for environment when disposed in high concentration is phenol. Currently, Phenol compound in textile industrial waste has reached 10 ppm meanwhile maximum allowable phenol concentration is not more than 0.2 ppm. Otherwise, Phenol also has economic value as feedstock of plastic, pharmaceutical and cosmetic industry. Furthermore, suitable method to separate phenol from waste water is needed. In this research, liquid - liquid extraction method was used with extraction time for 70 minutes. Waste water sample was then separated into two layers which are extract and raffinate. Thereafter, extract and raffinate were then tested by using UV-Vis Spectrophotometer to obtained liquid - liquid equilibrium data. Aim of this research is to study the effect of temperature, stirring speed and type of solvent to obtain distribution coefficient (Kd), phenol yield and correlation of Three-Suffix Margules model for the liquid - liquid extraction data equilibrium. The highest extraction yield at 80.43 % was found by using 70% methanol as solvent at extraction temperature 50 °C with stirring speed 300 rpm, coefficient distribution was found 216.334. From this research it can be concluded that Three-Suffix Margules Model is suitable to predict liquid - liquid equilibrium data for phenol system.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dierauf, Timothy; Kurtz, Sarah; Riley, Evan

This paper provides a recommended method for evaluating the AC capacity of a photovoltaic (PV) generating station. It also presents companion guidance on setting the facilitys capacity guarantee value. This is a principles-based approach that incorporates plant fundamental design parameters such as loss factors, module coefficients, and inverter constraints. This method has been used to prove contract guarantees for over 700 MW of installed projects. The method is transparent, and the results are deterministic. In contrast, current industry practices incorporate statistical regression where the empirical coefficients may only characterize the collected data. Though these methods may work well when extrapolationmore » is not required, there are other situations where the empirical coefficients may not adequately model actual performance.This proposed Fundamentals Approach method provides consistent results even where regression methods start to lose fidelity.« less

Multiscale image contrast amplification (MUSICA)

NASA Astrophysics Data System (ADS)

Vuylsteke, Pieter; Schoeters, Emile P.

1994-05-01

This article presents a novel approach to the problem of detail contrast enhancement, based on multiresolution representation of the original image. The image is decomposed into a weighted sum of smooth, localized, 2D basis functions at multiple scales. Each transform coefficient represents the amount of local detail at some specific scale and at a specific position in the image. Detail contrast is enhanced by non-linear amplification of the transform coefficients. An inverse transform is then applied to the modified coefficients. This yields a uniformly contrast- enhanced image without artefacts. The MUSICA-algorithm is being applied routinely to computed radiography images of chest, skull, spine, shoulder, pelvis, extremities, and abdomen examinations, with excellent acceptance. It is useful for a wide range of applications in the medical, graphical, and industrial area.

Quality by design: scale-up of freeze-drying cycles in pharmaceutical industry.

PubMed

Pisano, Roberto; Fissore, Davide; Barresi, Antonello A; Rastelli, Massimo

2013-09-01

This paper shows the application of mathematical modeling to scale-up a cycle developed with lab-scale equipment on two different production units. The above method is based on a simplified model of the process parameterized with experimentally determined heat and mass transfer coefficients. In this study, the overall heat transfer coefficient between product and shelf was determined by using the gravimetric procedure, while the dried product resistance to vapor flow was determined through the pressure rise test technique. Once model parameters were determined, the freeze-drying cycle of a parenteral product was developed via dynamic design space for a lab-scale unit. Then, mathematical modeling was used to scale-up the above cycle in the production equipment. In this way, appropriate values were determined for processing conditions, which allow the replication, in the industrial unit, of the product dynamics observed in the small scale freeze-dryer. This study also showed how inter-vial variability, as well as model parameter uncertainty, can be taken into account during scale-up calculations.

Hexavalent Chromium Removal from Model Water and Car Shock Absorber Factory Effluent by Nanofiltration and Reverse Osmosis Membrane

PubMed Central

Bejaoui, Imen; Mouelhi, Meral; Hamrouni, Béchir

2017-01-01

Nanofiltration and reverse osmosis are investigated as a possible alternative to the conventional methods of Cr(VI) removal from model water and industrial effluent. The influences of feed concentration, water recovery, pH, and the coexisting anions were studied. The results have shown that retention rates of hexavalent chromium can reach 99.7% using nanofiltration membrane (NF-HL) and vary from 85 to 99.9% using reverse osmosis membrane (RO-SG) depending upon the composition of the solution and operating conditions. This work was also extended to investigate the separation of Cr(VI) from car shock absorber factory effluent. The use of these membranes is very promising for Cr(VI) water treatment and desalting industry effluent. Spiegler-Kedem model was applied to experimental results in the aim to determine phenomenological parameters, the reflection coefficient of the membrane (σ), and the solute permeability coefficient (Ps). The convective and diffusive parts of the mass transfer were quantified with predominance of the diffusive contribution. PMID:28819360

Solubility and durability of cardanol derived plasticizers for soft PVC

NASA Astrophysics Data System (ADS)

Greco, Antonio; Ferrari, Francesca; Velardi, Rosario; Frigione, Mariaenrica; Maffezzoli, Alfonso

2015-12-01

This work is aimed to study the suitability of cardanol derivatives as primary plasticizer for PVC. The innovative plasticizer is obtained by chemical modification of cardanol, a natural, renewable resource, obtained as a by-product of the cashew nut shell industry. Cardanol derived plasticizers (CDP) were prepared by following various procedures, that allow obtaining different degrees of conversion of cardanol. Rheological and ageing tests were made on soft PVC produced by the addition of CDP;results obtained were compared to soft PVC attained by the use of di-ethyl-hexyl-phthalate (DEHP) and other natural derived plasticizers already used in PVC industry (epoxidated soybean oil, ESBO, and acetic acid ester, AAE).A high dependence on the degree of conversion was found: CDP with a good degree of conversion have similar gelation temperature and diffusion coefficient compared to DEHP based plastisols. Otherwise,CDP with a low degree of conversionshow a higher diffusion coefficient, index of a fast migration of the plasticizer from soft PVC.

Analysis of influential factors on haze pollution in China

NASA Astrophysics Data System (ADS)

Liu, Xiao-Hong; Jiang, Keshen

2018-05-01

This study tests the hypothesis of Environmental Kuznets Curve (EKC) between PM10 concentrations and economic growth and analyzes the influential factors of PM10 concentrations from the economic perspective by using the panel data on the PM10 concentrations of 30 provinces from 2003 to 2015 in China. Results of the regression estimation from the fully modified OLS (FMOLS) method show that a relationship characterized by an inverted U-shaped curve is observed between PM10 concentrations and gross domestic product (GDP) per capita and that an EKC exists in China’s haze pollution problem. PM10 concentrations have the most sensitive response to GDP. The elastic coefficients of the possession of civilian vehicles, urbanization and trade openness are positive values. More importantly, the elastic coefficient of the tertiary industry proportion is less than 0. Increase in the proportion of tertiary industry can effectively alleviate China’s problem on haze pollution. Lastly, relevant countermeasures and suggestions are presented.

A Comprehensive Estimation of the Economic Effects of Meteorological Services Based on the Input-Output Method

PubMed Central

Wu, Xianhua; Yang, Lingjuan; Guo, Ji; Lu, Huaguo; Chen, Yunfeng; Sun, Jian

2014-01-01

Concentrating on consuming coefficient, partition coefficient, and Leontief inverse matrix, relevant concepts and algorithms are developed for estimating the impact of meteorological services including the associated (indirect, complete) economic effect. Subsequently, quantitative estimations are particularly obtained for the meteorological services in Jiangxi province by utilizing the input-output method. It is found that the economic effects are noticeably rescued by the preventive strategies developed from both the meteorological information and internal relevance (interdependency) in the industrial economic system. Another finding is that the ratio range of input in the complete economic effect on meteorological services is about 1 : 108.27–1 : 183.06, remarkably different from a previous estimation based on the Delphi method (1 : 30–1 : 51). Particularly, economic effects of meteorological services are higher for nontraditional users of manufacturing, wholesale and retail trades, services sector, tourism and culture, and art and lower for traditional users of agriculture, forestry, livestock, fishery, and construction industries. PMID:24578666

A comprehensive estimation of the economic effects of meteorological services based on the input-output method.

PubMed

Wu, Xianhua; Wei, Guo; Yang, Lingjuan; Guo, Ji; Lu, Huaguo; Chen, Yunfeng; Sun, Jian

2014-01-01

Concentrating on consuming coefficient, partition coefficient, and Leontief inverse matrix, relevant concepts and algorithms are developed for estimating the impact of meteorological services including the associated (indirect, complete) economic effect. Subsequently, quantitative estimations are particularly obtained for the meteorological services in Jiangxi province by utilizing the input-output method. It is found that the economic effects are noticeably rescued by the preventive strategies developed from both the meteorological information and internal relevance (interdependency) in the industrial economic system. Another finding is that the ratio range of input in the complete economic effect on meteorological services is about 1 : 108.27-1 : 183.06, remarkably different from a previous estimation based on the Delphi method (1 : 30-1 : 51). Particularly, economic effects of meteorological services are higher for nontraditional users of manufacturing, wholesale and retail trades, services sector, tourism and culture, and art and lower for traditional users of agriculture, forestry, livestock, fishery, and construction industries.

Identification of structural damage using wavelet-based data classification

NASA Astrophysics Data System (ADS)

Koh, Bong-Hwan; Jeong, Min-Joong; Jung, Uk

2008-03-01

Predicted time-history responses from a finite-element (FE) model provide a baseline map where damage locations are clustered and classified by extracted damage-sensitive wavelet coefficients such as vertical energy threshold (VET) positions having large silhouette statistics. Likewise, the measured data from damaged structure are also decomposed and rearranged according to the most dominant positions of wavelet coefficients. Having projected the coefficients to the baseline map, the true localization of damage can be identified by investigating the level of closeness between the measurement and predictions. The statistical confidence of baseline map improves as the number of prediction cases increases. The simulation results of damage detection in a truss structure show that the approach proposed in this study can be successfully applied for locating structural damage even in the presence of a considerable amount of process and measurement noise.

Transport, Structural and Mechanical Properties of Quaternary FeVTiAl Alloy

NASA Astrophysics Data System (ADS)

Bhat, Tahir Mohiuddin; Gupta, Dinesh C.

2016-11-01

The electronic, structural, magnetic and transport properties of FeVTiAl quaternary alloy have been investigated within the framework of density functional theory. The material is a completely spin-polarized half-metallic ferromagnet in its ground state with F-43m structure. The structural stability was further confirmed by elastic constants in the cubic phase with high Young's modulus and brittle nature. The present study predicts an energy band gap of 0.72 eV in a localized minority spin channel at equilibrium lattice parameter of 6.00 Å. The transport properties of the material are discussed based on the Seebeck coefficient, and electrical and thermal conductivity coefficients. The alloy presents large values of Seebeck coefficients, ~39 μV K-1 at room temperature (300 K), and has an excellent thermoelectric performance with ZT = ~0.8.

An economic prediction of the finer resolution level wavelet coefficients in electronic structure calculations.

PubMed

Nagy, Szilvia; Pipek, János

2015-12-21

In wavelet based electronic structure calculations, introducing a new, finer resolution level is usually an expensive task, this is why often a two-level approximation is used with very fine starting resolution level. This process results in large matrices to calculate with and a large number of coefficients to be stored. In our previous work we have developed an adaptively refined solution scheme that determines the indices, where the refined basis functions are to be included, and later a method for predicting the next, finer resolution coefficients in a very economic way. In the present contribution, we would like to determine whether the method can be applied for predicting not only the first, but also the other, higher resolution level coefficients. Also the energy expectation values of the predicted wave functions are studied, as well as the scaling behaviour of the coefficients in the fine resolution limit.

An instrumental variable random-coefficients model for binary outcomes

PubMed Central

Chesher, Andrew; Rosen, Adam M

2014-01-01

In this paper, we study a random-coefficients model for a binary outcome. We allow for the possibility that some or even all of the explanatory variables are arbitrarily correlated with the random coefficients, thus permitting endogeneity. We assume the existence of observed instrumental variables Z that are jointly independent with the random coefficients, although we place no structure on the joint determination of the endogenous variable X and instruments Z, as would be required for a control function approach. The model fits within the spectrum of generalized instrumental variable models, and we thus apply identification results from our previous studies of such models to the present context, demonstrating their use. Specifically, we characterize the identified set for the distribution of random coefficients in the binary response model with endogeneity via a collection of conditional moment inequalities, and we investigate the structure of these sets by way of numerical illustration. PMID:25798048

Technical Efficiency of Automotive Industry Cluster in Chennai

NASA Astrophysics Data System (ADS)

Bhaskaran, E.

2012-07-01

Chennai is also called as Detroit of India due to its automotive industry presence producing over 40 % of the India's vehicle and components. During 2001-2002, diagnostic study was conducted on the Automotive Component Industries (ACI) in Ambattur Industrial Estate, Chennai and in SWOT analysis it was found that it had faced problems on infrastructure, technology, procurement, production and marketing. In the year 2004-2005 under the cluster development approach (CDA), they formed Chennai auto cluster, under public private partnership concept, received grant from Government of India, Government of Tamil Nadu, Ambattur Municipality, bank loans and stake holders. This results development in infrastructure, technology, procurement, production and marketing interrelationships among ACI. The objective is to determine the correlation coefficient, regression equation, technical efficiency, peer weights, slack variables and return to scale of cluster before and after the CDA. The methodology adopted is collection of primary data from ACI and analyzing using data envelopment analysis (DEA) of input oriented Banker-Charnes-Cooper model. There is significant increase in correlation coefficient and the regression analysis reveals that for one percent increase in employment and net worth, the gross output increases significantly after the CDA. The DEA solver gives the technical efficiency of ACI by taking shift, employment, net worth as input data and quality, gross output and export ratio as output data. From the technical score and ranking of ACI, it is found that there is significant increase in technical efficiency of ACI when compared to CDA. The slack variables obtained clearly reveals the excess employment and net worth and no shortage of gross output. To conclude there is increase in technical efficiency of not only Chennai auto cluster in general but also Chennai auto components industries in particular.

Building an R&D chemical registration system.

PubMed

Martin, Elyette; Monge, Aurélien; Duret, Jacques-Antoine; Gualandi, Federico; Peitsch, Manuel C; Pospisil, Pavel

2012-05-31

Small molecule chemistry is of central importance to a number of R&D companies in diverse areas such as the pharmaceutical, nutraceutical, food flavoring, and cosmeceutical industries. In order to store and manage thousands of chemical compounds in such an environment, we have built a state-of-the-art master chemical database with unique structure identifiers. Here, we present the concept and methodology we used to build the system that we call the Unique Compound Database (UCD). In the UCD, each molecule is registered only once (uniqueness), structures with alternative representations are entered in a uniform way (normalization), and the chemical structure drawings are recognizable to chemists and to a cartridge. In brief, structural molecules are entered as neutral entities which can be associated with a salt. The salts are listed in a dictionary and bound to the molecule with the appropriate stoichiometric coefficient in an entity called "substance". The substances are associated with batches. Once a molecule is registered, some properties (e.g., ADMET prediction, IUPAC name, chemical properties) are calculated automatically. The UCD has both automated and manual data controls. Moreover, the UCD concept enables the management of user errors in the structure entry by reassigning or archiving the batches. It also allows updating of the records to include newly discovered properties of individual structures. As our research spans a wide variety of scientific fields, the database enables registration of mixtures of compounds, enantiomers, tautomers, and compounds with unknown stereochemistries.

Commentary on Coefficient Alpha: A Cautionary Tale

ERIC Educational Resources Information Center

Green, Samuel B.; Yang, Yanyun

2009-01-01

The general use of coefficient alpha to assess reliability should be discouraged on a number of grounds. The assumptions underlying coefficient alpha are unlikely to hold in practice, and violation of these assumptions can result in nontrivial negative or positive bias. Structural equation modeling was discussed as an informative process both to…

A study of hierarchical structure on South China industrial electricity-consumption correlation

NASA Astrophysics Data System (ADS)

Yao, Can-Zhong; Lin, Ji-Nan; Liu, Xiao-Feng

2016-02-01

Based on industrial electricity-consumption data of five southern provinces of China from 2005 to 2013, we study the industrial correlation mechanism with MST (minimal spanning tree) and HT (hierarchical tree) models. First, we comparatively analyze the industrial electricity-consumption correlation structure in pre-crisis and after-crisis period using MST model and Bootstrap technique of statistical reliability test of links. Results exhibit that all industrial electricity-consumption trees of five southern provinces of China in pre-crisis and after-crisis time are in formation of chain, and the "center-periphery structure" of those chain-like trees is consistent with industrial specialization in classical industrial chain theory. Additionally, the industrial structure of some provinces is reorganized and transferred in pre-crisis and after-crisis time. Further, the comparative analysis with hierarchical tree and Bootstrap technique demonstrates that as for both observations of GD and overall NF, the industrial electricity-consumption correlation is non-significant clustered in pre-crisis period, whereas it turns significant clustered in after-crisis time. Therefore we propose that in perspective of electricity-consumption, their industrial structures are directed to optimized organization and global correlation. Finally, the analysis of distance of HTs verifies that industrial reorganization and development may strengthen market integration, coordination and correlation of industrial production. Except GZ, other four provinces have a shorter distance of industrial electricity-consumption correlation in after-crisis period, revealing a better performance of regional specialization and integration.

Coupled electro-thermal field in a high current electrolysis cell or liquid metal batteries

PubMed Central

Cai, Liwei; Ni, Haiou; Lu, Gui-Min; Yu, Jian-Guo

2018-01-01

Coupled electro-thermal field exists widely in chemical batteries and electrolysis industry. In this study, a three-dimensional numerical model, which is based on the finite-element software ANSYS, has been built to simulate the electro-thermal field in a magnesium electrolysis cell. The adjustment of the relative position of the anode and cathode can change the energy consumption of the magnesium electrolysis process significantly. Besides, the current intensity has a nonlinear effect on heat balance, and the effects of heat transfer coefficients, electrolysis and air temperature on the heat balance have been released to maintain the thermal stability in a magnesium electrolysis cell. The relationship between structure as well as process parameters and electro-thermal field has been obtained and the simulation results can provide experience for the scale-up design in liquid metal batteries. PMID:29515848

Chemical growth of ZnO nanorod arrays on textured nanoparticle nanoribbons and its second-harmonic generation performance

NASA Astrophysics Data System (ADS)

Gui, Zhou; Wang, Xian; Liu, Jian; Yan, Shanshan; Ding, Yanyan; Wang, Zhengzhou; Hu, Yuan

2006-07-01

On the basis of the highly oriented ZnO nanoparticle nanoribbons as the growth seed layer (GSL) and solution growth technique, we have synthesized vertical ZnO nanorod arrays with high density over a large area and multi-teeth brush nanostructure, respectively, according to the density degree of the arrangement of nanoparticle nanoribbons GSL on the glass substrate. This controllable and convenient technique opens the possibility of creating nanostructured film for industrial fabrication and may represent a facile way to get similar structures of other compounds by using highly oriented GSL to promote the vertical arrays growth. The growth mechanism of the formation of the ordered nanorod arrays is also discussed. The second-order nonlinear optical coefficient d31 of the vertical ZnO nanorod arrays measured by the Maker fringes technique is 11.3 times as large as that of d36 KH 2PO 4 (KDP).

Rheological behavior, emulsifying properties and structural characterization of phosphorylated fish gelatin.

PubMed

Huang, Tao; Tu, Zong-Cai; Shangguan, Xinchen; Wang, Hui; Sha, Xiaomei; Bansal, Nidhi

2018-04-25

Rheological, microstructural and emulsifying properties of fish gelatin phosphorylated using sodium trimetaphosphate (STMP) were studied. Phosphorylation was carried out at 50 °C for 0, 0.5, 1 or 2 h. Rheological behaviors indicated that phosphorylation decreased gelation rate constant (k gel ) and apparent viscosity of gelatin solutions. Phosphorylation time was inversely proportional to tan δ; gelling and melting points of fish gelatin gels; however gel properties could be improved by short time of phosphorylation. Scanning electron microscopy and atomic force microscopy revealed that longer time of phosphorylation resulted in looser gel network with more aggregation. Longer phosphorylation time could stabilize fish gelatin emulsions, and endowed emulsions with smaller particle size and lower coefficient viscosity, but higher ζ-potential values. These results suggested that phosphorylation could be applied to obtain fish gelatin with varying functional properties suitable for numerous industrial applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

Determining the Size of Pores in a Partially Transparent Ceramics from Total-Reflection Spectra

NASA Astrophysics Data System (ADS)

Mironov, R. A.; Zabezhailov, M. O.; Georgiu, I. F.; Cherepanov, V. V.; Rusin, M. Yu.

2018-03-01

A technique is proposed for determining the pore-size distribution based on measuring the dependence of total reflectance in the domain of partial transparency of a material. An assumption about equality of scattering-coefficient spectra determined by solving the inverse radiation transfer problem and by theoretical calculation with the Mie theory is used. The technique is applied to studying a quartz ceramics. The poresize distribution is also determined using mercury and gas porosimetry. All three methods are shown to produce close results for pores with diameters of <180 nm, which occupy 90% of the void volume. In the domain of pore dimensions of >180 nm, the methods show differences that might be related to both specific procedural features and the structural properties of ceramics. The spectral-scattering method has a number of advantages over traditional porosimetry, and it can be viewed as a routine industrial technique.

An evaluation of tannery industry wastewater treatment sludge gasification by artificial neural network modeling.

PubMed

Ongen, Atakan; Ozcan, H Kurtulus; Arayıcı, Semiha

2013-12-15

This paper reports on the calorific value of synthetic gas (syngas) produced by gasification of dewatered sludge derived from treatment of tannery wastewater. Proximate and ultimate analyses of samples were performed. Thermochemical conversion alters the chemical structure of the waste. Dried air was used as a gasification agent at varying flow rates, which allowed the feedstock to be quickly converted into gas by means of different heterogeneous reactions. A lab-scale updraft fixed-bed steel reactor was used for thermochemical conversion of sludge samples. Artificial neural network (ANN) modeling techniques were used to observe variations in the syngas related to operational conditions. Modeled outputs showed that temporal changes of model predictions were in close accordance with real values. Correlation coefficients (r) showed that the ANN used in this study gave results with high sensitivity. Copyright © 2013 Elsevier B.V. All rights reserved.

A relationship between the effect of uni-univalent electrolytes on the structure of water and on its volatility

NASA Astrophysics Data System (ADS)

Marcus, Yizhak

2018-06-01

The effect of ions on the structure of water in dilute solutions, whether they are structure-makers or structure-breakers, is manifested also in the volatility of the water. For more than 40 uni-univalent electrolytes, there is a linearly increasing relationship between 2φ(m = 0.4) - φ(m = 0.2), where φ is the osmotic coefficient and m is the molality, and the difference between the viscosity B-coefficients of the cation and anion. Exceptions to this relationship are electrolytes with highly structure-making anions and with hydrophobic cations.

Acousto-optical and SAW propagation characteristics of temperature stable multilayered structures based on LiNbO3 and diamond

NASA Astrophysics Data System (ADS)

Shandilya, Swati; Sreenivas, K.; Gupta, Vinay

2008-01-01

Theoretical studies on the surface acoustic wave (SAW) properties of c-axis oriented LiNbO3/IDT/diamond and diamond/IDT/128° rotated Y-X cut LiNbO3 multilayered structures have been considered. Both layered structures exhibit a positive temperature coefficient of delay (TCD) characteristic, and a zero TCD device is obtained after integrating with an over-layer of either tellurium dioxide (TeO2) or silicon dioxide (SiO2). The presence of a TeO2 over-layer enhanced the electromechanical coupling coefficients of both multilayered structures, which acts as a better temperature compensation layer than SiO2. The temperature stable TeO2/LiNbO3/IDT/diamond layered structure exhibits good electromechanical coefficient and higher phase velocity for SAW device applications. On the other hand, a high acousto-optical (AO) figure of merit (30-37) × 10-15 s3 kg-1 has been obtained for the temperature stable SiO2/diamond/IDT/LiNbO3 layered structure indicating a promising device structure for AO applications.

Integration Of Heat Transfer Coefficient In Glass Forming Modeling With Special Interface Element

NASA Astrophysics Data System (ADS)

Moreau, P.; César de Sá, J.; Grégoire, S.; Lochegnies, D.

2007-05-01

Numerical modeling of the glass forming processes requires the accurate knowledge of the heat exchange between the glass and the forming tools. A laboratory testing is developed to determine the evolution of the heat transfer coefficient in different glass/mould contact conditions (contact pressure, temperature, lubrication…). In this paper, trials are performed to determine heat transfer coefficient evolutions in experimental conditions close to the industrial blow-and-blow process conditions. In parallel of this work, a special interface element is implemented in a commercial Finite Element code in order to deal with heat transfer between glass and mould for non-meshing meshes and evolutive contact. This special interface element, implemented by using user subroutines, permits to introduce the previous heat transfer coefficient evolutions in the numerical modelings at the glass/mould interface in function of the local temperatures, contact pressures, contact time and kind of lubrication. The blow-and-blow forming simulation of a perfume bottle is finally performed to assess the special interface element performance.

FIBER AND INTEGRATED OPTICS: Reflection of electromagnetic radiation from a multilayer waveguide structure with an absorbing metal layer

NASA Astrophysics Data System (ADS)

Chernushich, A. P.; Shkerdin, G. N.; Shukin, Yu M.

1992-10-01

The angular distribution of the reflection coefficient of an asymmetric multilayer planar structure containing a thin metal film and a planar optical waveguide has been found by accurate numerical calculations. There are resonances in the reflection coefficient associated with hybrid modes of the structure. The cases of strong and weak coupling of the surface polariton modes with the waveguide modes are discussed. The results of the numerical analysis agree with solutions of Maxwell's equations for a multilayer planar structure.

Rate Constants for Fine-Structure Excitations in O - H Collisions with Error Bars Obtained by Machine Learning

NASA Astrophysics Data System (ADS)

Vieira, Daniel; Krems, Roman

2017-04-01

Fine-structure transitions in collisions of O(3Pj) with atomic hydrogen are an important cooling mechanism in the interstellar medium; knowledge of the rate coefficients for these transitions has a wide range of astrophysical applications. The accuracy of the theoretical calculation is limited by inaccuracy in the ab initio interaction potentials used in the coupled-channel quantum scattering calculations from which the rate coefficients can be obtained. In this work we use the latest ab initio results for the O(3Pj) + H interaction potentials to improve on previous calculations of the rate coefficients. We further present a machine-learning technique based on Gaussian Process regression to determine the sensitivity of the rate coefficients to variations of the underlying adiabatic interaction potentials. To account for the inaccuracy inherent in the ab initio calculations we compute error bars for the rate coefficients corresponding to 20% variation in each of the interaction potentials. We obtain these error bars by fitting a Gaussian Process model to a data set of potential curves and rate constants. We use the fitted model to do sensitivity analysis, determining the relative importance of individual adiabatic potential curves to a given fine-structure transition. NSERC.

Macroscopic damping model for structural dynamics with random polycrystalline configurations

NASA Astrophysics Data System (ADS)

Yang, Yantao; Cui, Junzhi; Yu, Yifan; Xiang, Meizhen

2018-06-01

In this paper the macroscopic damping model for dynamical behavior of the structures with random polycrystalline configurations at micro-nano scales is established. First, the global motion equation of a crystal is decomposed into a set of motion equations with independent single degree of freedom (SDOF) along normal discrete modes, and then damping behavior is introduced into each SDOF motion. Through the interpolation of discrete modes, the continuous representation of damping effects for the crystal is obtained. Second, from energy conservation law the expression of the damping coefficient is derived, and the approximate formula of damping coefficient is given. Next, the continuous damping coefficient for polycrystalline cluster is expressed, the continuous dynamical equation with damping term is obtained, and then the concrete damping coefficients for a polycrystalline Cu sample are shown. Finally, by using statistical two-scale homogenization method, the macroscopic homogenized dynamical equation containing damping term for the structures with random polycrystalline configurations at micro-nano scales is set up.

Self-diffusion Coefficient and Structure of Binary n-Alkane Mixtures at the Liquid-Vapor Interfaces.

PubMed

Chilukoti, Hari Krishna; Kikugawa, Gota; Ohara, Taku

2015-10-15

The self-diffusion coefficient and molecular-scale structure of several binary n-alkane liquid mixtures in the liquid-vapor interface regions have been examined using molecular dynamics simulations. It was observed that in hexane-tetracosane mixture hexane molecules are accumulated in the liquid-vapor interface region and the accumulation intensity decreases with increase in a molar fraction of hexane in the examined range. Molecular alignment and configuration in the interface region of the liquid mixture change with a molar fraction of hexane. The self-diffusion coefficient in the direction parallel to the interface of both tetracosane and hexane in their binary mixture increases in the interface region. It was found that the self-diffusion coefficient of both tetracosane and hexane in their binary mixture is considerably higher in the vapor side of the interface region as the molar fraction of hexane goes lower, which is mostly due to the increase in local free volume caused by the local structure of the liquid in the interface region.

Optical analysis of thermal induced structural distortions

NASA Technical Reports Server (NTRS)

Weinswig, Shepard; Hookman, Robert A.

1991-01-01

The techniques used for the analysis of thermally induced structural distortions of optical components such as scanning mirrors and telescope optics are outlined. Particular attention is given to the methodology used in the thermal and structural analysis of the GOES scan mirror, the optical analysis using Zernike coefficients, and the optical system performance evaluation. It is pointed out that the use of Zernike coefficients allows an accurate, effective, and simple linkage between thermal/mechanical effects and the optical design.

The excitation of OH by H2 revisited - I: fine-structure resolved rate coefficients

NASA Astrophysics Data System (ADS)

Kłos, J.; Ma, Q.; Dagdigian, P. J.; Alexander, M. H.; Faure, A.; Lique, F.

2017-11-01

Observations of OH in molecular clouds provide crucial constraints on both the physical conditions and the oxygen and water chemistry in these clouds. Accurate modelling of the OH emission spectra requires the calculation of rate coefficients for excitation of OH by collisions with the most abundant collisional partner in the molecular clouds, namely the H2 molecule. We report here theoretical calculations for the fine-structure excitation of OH by H2 (both para- and ortho-H2) using a recently developed highly accurate potential energy surface. Full quantum close coupling rate coefficients are provided for temperatures ranging from 10 to 150 K. Propensity rules are discussed and the new OH-H2 rate coefficients are compared to the earlier values that are currently used in astrophysical modelling. Significant differences were found: the new rate coefficients are significantly larger. As a first application, we simulate the excitation of OH in typical cold molecular clouds and star-forming regions. The new rate coefficients predict substantially larger line intensities. As a consequence, OH abundances derived from observations will be reduced from the values predicted by the earlier rate coefficients.

Predicting cyclohexane/water distribution coefficients for the SAMPL5 challenge using MOSCED and the SMD solvation model

NASA Astrophysics Data System (ADS)

Diaz-Rodriguez, Sebastian; Bozada, Samantha M.; Phifer, Jeremy R.; Paluch, Andrew S.

2016-11-01

We present blind predictions using the solubility parameter based method MOSCED submitted for the SAMPL5 challenge on calculating cyclohexane/water distribution coefficients at 298 K. Reference data to parameterize MOSCED was generated with knowledge only of chemical structure by performing solvation free energy calculations using electronic structure calculations in the SMD continuum solvent. To maintain simplicity and use only a single method, we approximate the distribution coefficient with the partition coefficient of the neutral species. Over the final SAMPL5 set of 53 compounds, we achieved an average unsigned error of 2.2± 0.2 log units (ranking 15 out of 62 entries), the correlation coefficient ( R) was 0.6± 0.1 (ranking 35), and 72± 6 % of the predictions had the correct sign (ranking 30). While used here to predict cyclohexane/water distribution coefficients at 298 K, MOSCED is broadly applicable, allowing one to predict temperature dependent infinite dilution activity coefficients in any solvent for which parameters exist, and provides a means by which an excess Gibbs free energy model may be parameterized to predict composition dependent phase-equilibrium.

Market Structure, Financial Dependence and Industrial Growth: Evidence from the Banking Industry in Emerging Asian Economies.

PubMed

Khan, Habib Hussain; Ahmad, Rubi Binit; Gee, Chan Sok

2016-01-01

In this study, we examine the role of market structure for growth in financially dependent industries from 10 emerging Asian economies over the period of 1995-2011. Our approach departs from existing studies in that we apply four alternative measures of market structure based on structural and non-structural approaches and compare their outcomes. Results indicate that higher bank concentration may slow down the growth of financially dependent industries. Bank competition on the other hand, allows financially dependent industries to grow faster. These findings are consistent across a number of sensitivity checks such as alternative measures of financial dependence, institutional factors (including property rights, quality of accounting standards and bank ownership), and endogeneity consideration. In sum, our study suggests that financially dependent industries grow more in more competitive/less concentrated banking systems. Therefore, regulatory authorities need to be careful while pursuing a consolidation policy for banking sector in emerging Asian economies.

Principal Component Analysis Based Measure of Structural Holes

NASA Astrophysics Data System (ADS)

Deng, Shiguo; Zhang, Wenqing; Yang, Huijie

2013-02-01

Based upon principal component analysis, a new measure called compressibility coefficient is proposed to evaluate structural holes in networks. This measure incorporates a new effect from identical patterns in networks. It is found that compressibility coefficient for Watts-Strogatz small-world networks increases monotonically with the rewiring probability and saturates to that for the corresponding shuffled networks. While compressibility coefficient for extended Barabasi-Albert scale-free networks decreases monotonically with the preferential effect and is significantly large compared with that for corresponding shuffled networks. This measure is helpful in diverse research fields to evaluate global efficiency of networks.

Laboratory Study of the OH + Permethylsiloxane (L2, L3, D3, and D4) Reaction Rate Coefficients Between 240 and 370 K

NASA Astrophysics Data System (ADS)

Burkholder, J. B.; Bernard, F.; Papadimitriou, V. C.

2016-12-01

The atmospheric chemistry of organosiloxanes has recently been implicated in the formation of new particles as well as regional and indoor air quality. Methylsiloxanes with Si<6 are relatively volatile compounds with either linear or cyclic molecular structures. Methylsiloxanes are found in consumer goods such as cosmetics, textiles, health care and household products and in industrial applications as solvents and lubricants. They are released into the atmosphere during manufacturing, use, and disposal and have been observed in the atmosphere in ppb levels in certain locations. However, the fundamental chemical properties of this class of compounds, particularly their reactivity with the OH radical, are presently not fully characterized. In this work, the temperature dependence of the rate coefficients for the OH radical reaction with the simplest linear (L2 and L3) and cyclic (D3 and D4) siloxanes were measured: OH + (CH3)3SiOSi(CH3)3 = Products L2OH + [(CH3)3SiO]2Si(CH3)2 = Products L3OH + [-Si(CH3)2O-]3 = Products D3OH + [-Si(CH3)2O-]4 = Products D4OH rate coefficients were measured under pseudo-first conditions in OH over the temperature range 240-370 K using a pulsed laser photolysis-laser induced fluorescence (PLP-LIF) technique and at 296 K using a relative rate method. The present results are compared with available literature data where possible and discrepancies are discussed. The results from this work will be discussed in terms of the atmospheric lifetimes of these methylsiloxanes and the reactivity trends for this class of compound.

[Correlation of substrate structure and hydraulic characteristics in subsurface flow constructed wetlands].

PubMed

Bai, Shao-Yuan; Song, Zhi-Xin; Ding, Yan-Li; You, Shao-Hong; He, Shan

2014-02-01

The correlation of substrate structure and hydraulic characteristics was studied by numerical simulation combined with experimental method. The numerical simulation results showed that the permeability coefficient of matrix had a great influence on hydraulic efficiency in subsurface flow constructed wetlands. The filler with a high permeability coefficient had a worse flow field distribution in the constructed wetland with single layer structure. The layered substrate structure with the filler permeability coefficient increased from surface to bottom could avoid the short-circuited flow and dead-zones, and thus, increased the hydraulic efficiency. Two parallel pilot-scale constructed wetlands were built according to the numerical simulation results, and tracer experiments were conducted to validate the simulation results. The tracer experiment result showed that hydraulic characteristics in the layered constructed wetland were obviously better than that in the single layer system, and the substrate effective utilization rates were 0.87 and 0.49, respectively. It was appeared that numerical simulation would be favorable for substrate structure optimization in subsurface flow constructed wetlands.

Research on soundproof properties of cylindrical shells of generalized phononic crystals

NASA Astrophysics Data System (ADS)

Liu, Ru; Shu, Haisheng; Wang, Xingguo

2017-04-01

Based on the previous studies, the concept of generalized phononic crystals (GPCs) is further introduced into the cylindrical shell structures in this paper. And a type of cylindrical shells of generalized phononic crystals (CS-GPCs) is constructed, the structural field and acoustic-structural coupled field of the composite cylindrical shells are examined respectively. For the structural field, the transfer matrix method of mechanical state vector is adopted to build the transfer matrix of radial waves propagating from inside to outside. For the acoustic-structural coupled field, the expressions of the acoustic transmission/reflection coefficients and the sound insulation of acoustic waves with the excitation of center line sound source are set up. And the acoustic transmission coefficient and the frequency response of sound insulation in this mode were numerical calculated. Furthermore, the theoretical analysis results are verified by using the method of combining the numerical calculation and finite element simulation. Finally, the effects of inner and outer fluid parameters on the transmission/reflection coefficients of CS-GPCs are analyzed in detail.

Interpreting Regression Results: beta Weights and Structure Coefficients are Both Important.

ERIC Educational Resources Information Center

Thompson, Bruce

Various realizations have led to less frequent use of the "OVA" methods (analysis of variance--ANOVA--among others) and to more frequent use of general linear model approaches such as regression. However, too few researchers understand all the various coefficients produced in regression. This paper explains these coefficients and their…

Thermodynamics of Boron Removal from Silicon Using CaO-MgO-Al2O3-SiO2 Slags

NASA Astrophysics Data System (ADS)

Jakobsson, Lars Klemet; Tangstad, Merete

2018-04-01

Slag refining is one of few metallurgical methods for removal of boron from silicon. It is important to know the thermodynamic properties of boron in slags to understand the refining process. The relation of the distribution coefficient of boron to the activity of silica, partial pressure of oxygen, and capacity of slags for boron oxide was investigated. The link between these parameters explains why the distribution coefficient of boron does not change much with changing slag composition. In addition, the thermodynamic properties of dilute boron oxide in CaO-MgO-Al2O3-SiO2 slags was determined. The ratio of the activity coefficient of boron oxide and silica was found to be the most important parameter for understanding changes in the distribution coefficient of boron for different slags. Finally, the relation between the activity coefficient of boron oxide and slag structure was investigated. It was found that the structure can explain how the distribution coefficient of boron changes depending on slag composition.

Priority design parameters of industrialized optical fiber sensors in civil engineering

NASA Astrophysics Data System (ADS)

Wang, Huaping; Jiang, Lizhong; Xiang, Ping

2018-03-01

Considering the mechanical effects and the different paths for transferring deformation, optical fiber sensors commonly used in civil engineering have been systematically classified. Based on the strain transfer theory, the relationship between the strain transfer coefficient and allowable testing error is established. The proposed relationship is regarded as the optimal control equation to obtain the optimal value of sensors that satisfy the requirement of measurement precision. Furthermore, specific optimization design methods and priority design parameters of the classified sensors are presented. This research indicates that (1) strain transfer theory-based optimization design method is much suitable for the sensor that depends on the interfacial shear stress to transfer the deformation; (2) the priority design parameters are bonded (sensing) length, interfacial bonded strength, elastic modulus and radius of protective layer and thickness of adhesive layer; (3) the optimization design of sensors with two anchor pieces at two ends is independent of strain transfer theory as the strain transfer coefficient can be conveniently calibrated by test, and this kind of sensors has no obvious priority design parameters. Improved calibration test is put forward to enhance the accuracy of the calibration coefficient of end-expanding sensors. By considering the practical state of sensors and the testing accuracy, comprehensive and systematic analyses on optical fiber sensors are provided from the perspective of mechanical actions, which could scientifically instruct the application design and calibration test of industrialized optical fiber sensors.

Experience-based learning on determining the frictional coefficients of thermoset polymers incorporated with silicon carbide whiskers and chopped carbon fibers at different temperatures

NASA Astrophysics Data System (ADS)

Harrison, Edward; Alamir, Mohammed; Alzahrani, Naif; Asmatulu, Ramazan

2017-04-01

High temperature applications of materials have been increasing for various industrial applications, such as automobile brakes, clutches and thrust pads. The big portion of these materials are made out of the polymeric materials with various reinforcements. In the present study, high temperature polymeric materials were incorporated with SiC whiskers and chopped carbon fibers at 0, 5, 10 and 20wt.% and molded into desired size and shape prior to the curing process. These inclusions were selected because of their high mechanical strengths and thermal conductivity values to easily dissipate the frictional heat energy and sustain more external loads. The method of testing involves a metal ramp with an adjustable incline to find the coefficients of static and kinetic frictions by recording time and the angle of movement at various temperatures (e.g., -10°C and 50°C). The test results indicated that increasing the inclusions made drastic improvements on the coefficients of static and kinetic frictions. The undergraduate students were involved in the project and observed all the details of the process during the laboratory studies, as well as data collection, analysis and presentation. This study will be useful for the future trainings of the undergraduate engineering students on the composite, automobile and other manufacturing industries.

Discrete Haar transform and protein structure.

PubMed

Morosetti, S

1997-12-01

The discrete Haar transform of the sequence of the backbone dihedral angles (phi and psi) was performed over a set of X-ray protein structures of high resolution from the Brookhaven Protein Data Bank. Afterwards, the new dihedral angles were calculated by the inverse transform, using a growing number of Haar functions, from the lower to the higher degree. New structures were obtained using these dihedral angles, with standard values for bond lengths and angles, and with omega = 0 degree. The reconstructed structures were compared with the experimental ones, and analyzed by visual inspection and statistical analysis. When half of the Haar coefficients were used, all the reconstructed structures were not yet collapsed to a tertiary folding, but they showed yet realized most of the secondary motifs. These results indicate a substantial separation of structural information in the space of Haar transform, with the secondary structural information mainly present in the Haar coefficients of lower degrees, and the tertiary one present in the higher degree coefficients. Because of this separation, the representation of the folded structures in the space of Haar transform seems a promising candidate to encompass the problem of premature convergence in genetic algorithms.

CMOS compatible IR sensors by cytochrome c protein

NASA Astrophysics Data System (ADS)

Liao, Chien-Jen; Su, Guo-Dung

2013-09-01

In recent years, due to the progression of the semiconductor industrial, the uncooled Infrared sensor - microbolometer has opened the opportunity for achieving low cost infrared imaging systems for both military and commercial applications. Therefore, various fabrication processes and different materials based microbolometer have been developed sequentially. The cytochrome c (protein) thin film has be reported high temperature coefficient of resistance (TCR), which is related to the performance of microbolometer directly. Hence the superior TCR value will increase the performance of microbolometer. In this paper, we introduced a novel fabrication process using aluminum which is compatible with the Taiwan Semiconductor Manufacture Company (TSMC) D35 2P4M process as the main structure material, which benefits the device to integrate with readout integrated circuit (ROIC).The aluminum split structure is suspended by sacrificial layer utilizing the standard photolithography technology and chemical etching. The height and thickness of the structure are already considered. Besides, cytochrome c solutions were ink-jetted onto the aluminum structure by using the inkjet printer, applying precise control of the Infrared absorbing layer. In measurement, incident Infrared radiation can be detected and later the heat can be transmitted to adjacent pads to readout the signal. This approach applies an inexpensive and simple fabrication process and makes the device suitable for integration. In addition, the performance can be further improved with low noise readout circuits.

Enhancement of gravimetric forced flow through system to determine sorption, swelling, and mass transfer characteristics of liquid sorbents

NASA Astrophysics Data System (ADS)

Dresp, G.; Petermann, M.; Fieback, T. M.

2018-04-01

An existing apparatus for forced flow through of liquid sorbents has been enhanced with an optically accessible system including a transparent crucible, high pressure viewing cell, and camera. With this optical system, the active surface area between gas and liquid can be determined in situ for the first time under industrial process conditions while maintaining the accuracy of a magnetic suspension balance. Additionally, occurring swelling and the resulting buoyancy changes can now be corrected, further improving the quality of the data. Validation measurements focusing on the sorption isotherms, swelling, and bubble geometry of 1-butyl-3-methylimidazolium tetrafluoroborate with nitrogen at 303 K and up to 17 MPa, as well as with carbon dioxide at 303 K, 323 K, and 373 K at up to 3.5 MPa were completed. Absorption of nitrogen resulted in no observable volume change, whereas absorption of carbon dioxide resulted in temperature independent swelling of up to 9.8%. The gas bubble's structure and behavior during its ascend through the liquid was optically tracked in situ. Combining these two data sets with the absorption kinetics forms the basis to determine the measuring system independent mass transfer coefficients, which are applicable in other laboratory scale and industrial processes.

Case study: apparel industry waste management: a focus on recycling in South Africa.

PubMed

Larney, M; van Aardt, A M

2010-01-01

The need for effective apparel waste management is motivated by the increasing cost and decreasing availability of landfill space and the dwindling of natural resources. The aim of this study was to identify the current solid waste disposal and recycling practices of the apparel industry in South Africa and to determine their attitude and willingness towards recycling, their perception of the feasibility thereof, barriers to recycling and marketing strategies that would be appropriate for products made from recycled materials. A structured questionnaire was mailed to apparel manufacturers in South Africa. The results indicated that most apparel manufacturers use landfills to dispose of their waste, while approximately half recycle some of the waste. They are fairly positive towards recycling, with consideration of economical feasibility. Phi-coefficients show no practically significant relationship between company size and the use of recycled materials. The most important barriers to recycling are lack of equipment and technology, lack of material to recycle and lack of consumer awareness. Marketing strategies for recycled products are recommended. It is concluded that consumer awareness and knowledge regarding recycled apparel products should be developed in order to ensure a market and that apparel manufacturers should be encouraged to recycle more extensively, in order to ensure that resources will not be exhausted unnecessarily and the environment will be preserved optimally.

A QSPR model for prediction of diffusion coefficient of non-electrolyte organic compounds in air at ambient condition.

PubMed

Mirkhani, Seyyed Alireza; Gharagheizi, Farhad; Sattari, Mehdi

2012-03-01

Evaluation of diffusion coefficients of pure compounds in air is of great interest for many diverse industrial and air quality control applications. In this communication, a QSPR method is applied to predict the molecular diffusivity of chemical compounds in air at 298.15K and atmospheric pressure. Four thousand five hundred and seventy nine organic compounds from broad spectrum of chemical families have been investigated to propose a comprehensive and predictive model. The final model is derived by Genetic Function Approximation (GFA) and contains five descriptors. Using this dedicated model, we obtain satisfactory results quantified by the following statistical results: Squared Correlation Coefficient=0.9723, Standard Deviation Error=0.003 and Average Absolute Relative Deviation=0.3% for the predicted properties from existing experimental values. Copyright © 2011 Elsevier Ltd. All rights reserved.

Implementation of Structures in the CMS: Part 2, Weir

DTIC Science & Technology

2013-08-01

sharp - crested weir , it is between 0.55 and 0.58, and a broad - crested ...implementation, different weir coefficients are specified for the weir structure design, sharp - crested or broad - crested weir . The lowest value in the...coefficient range is used for the sharp - crested (0.55) and broad - crested (0.46) weir , respectively; the flux comparison between these two

Probing the Interplay of Size, Shape, and Solution Environment in Macromolecular Diffusion Using a Simple Refraction Experiment

ERIC Educational Resources Information Center

Mankidy, Bijith D.; Coutinho, Cecil A.; Gupta, Vinay K.

2010-01-01

The diffusion coefficient of polymers is a critical parameter in biomedicine, catalysis, chemical separations, nanotechnology, and other industrial applications. Here, measurement of macromolecular diffusion in solutions is described using a visually instructive, undergraduate-level optical refraction experiment based on Weiner's method. To…

77 FR 12590 - Winchester Industries; Analysis of Proposed Consent Order To Aid Public Comment

Federal Register 2010, 2011, 2012, 2013, 2014

2012-03-01

... homeowners can realize by replacing their windows, including the home's geographic location, size, insulation... insulation in a specific region). The performance standard imposed under this Part constitutes fencing-in... costs, heating and cooling costs, U-factor, solar heat gain coefficient, R-value, K-value, insulating...

Hypersonic CFD applications at NASA Langley using CFL3D and CFL3DE

NASA Technical Reports Server (NTRS)

Richardson, Pamela F.

1989-01-01

The CFL3D/CFL3DE CFD codes and the industrial use status of the codes are outlined. Comparison of grid density, pressure, heat transfer, and aerodynamic coefficience are presented. Future plans related to the National Aerospace Plane Program are briefly outlined.

Production of a Biopolymer at Reactor Scale: A Laboratory Experience

ERIC Educational Resources Information Center

Genc, Rukan; Rodriguez-Couto, Susana

2011-01-01

Undergraduate students of biotechnology became familiar with several aspects of bioreactor operation via the production of xanthan gum, an industrially relevant biopolymer, by "Xanthomonas campestris" bacteria. The xanthan gum was extracted from the fermentation broth and the yield coefficient and productivity were calculated. (Contains 2 figures.)

Flow temporal reconstruction from non-time-resolved data part I: mathematic fundamentals

NASA Astrophysics Data System (ADS)

Legrand, Mathieu; Nogueira, José; Lecuona, Antonio

2011-10-01

At least two circumstances point to the need of postprocessing techniques to recover lost time information from non-time-resolved data: the increasing interest in identifying and tracking coherent structures in flows of industrial interest and the high data throughput of global measuring techniques, such as PIV, for the validation of computational fluid dynamics (CFD) codes. This paper offers the mathematic fundamentals of a space--time reconstruction technique from non-time-resolved, statistically independent data. An algorithm has been developed to identify and track traveling coherent structures in periodic flows. Phase-averaged flow fields are reconstructed with a correlation-based method, which uses information from the Proper Orthogonal Decomposition (POD). The theoretical background shows that the snapshot POD coefficients can be used to recover flow phase information. Once this information is recovered, the real snapshots are used to reconstruct the flow history and characteristics, avoiding neither the use of POD modes nor any associated artifact. The proposed time reconstruction algorithm is in agreement with the experimental evidence given by the practical implementation proposed in the second part of this work (Legrand et al. in Exp Fluids, 2011), using the coefficients corresponding to the first three POD modes. It also agrees with the results on similar issues by other authors (Ben Chiekh et al. in 9 Congrès Francophone de Vélocimétrie Laser, Bruxelles, Belgium, 2004; Van Oudheusden et al. in Exp Fluids 39-1:86-98, 2005; Meyer et al. in 7th International Symposium on Particle Image Velocimetry, Rome, Italy, 2007a; in J Fluid Mech 583:199-227, 2007b; Perrin et al. in Exp Fluids 43-2:341-355, 2007). Computer time to perform the reconstruction is relatively short, of the order of minutes with current PC technology.

Fault-Tolerant Heat Exchanger

NASA Technical Reports Server (NTRS)

Izenson, Michael G.; Crowley, Christopher J.

2005-01-01

A compact, lightweight heat exchanger has been designed to be fault-tolerant in the sense that a single-point leak would not cause mixing of heat-transfer fluids. This particular heat exchanger is intended to be part of the temperature-regulation system for habitable modules of the International Space Station and to function with water and ammonia as the heat-transfer fluids. The basic fault-tolerant design is adaptable to other heat-transfer fluids and heat exchangers for applications in which mixing of heat-transfer fluids would pose toxic, explosive, or other hazards: Examples could include fuel/air heat exchangers for thermal management on aircraft, process heat exchangers in the cryogenic industry, and heat exchangers used in chemical processing. The reason this heat exchanger can tolerate a single-point leak is that the heat-transfer fluids are everywhere separated by a vented volume and at least two seals. The combination of fault tolerance, compactness, and light weight is implemented in a unique heat-exchanger core configuration: Each fluid passage is entirely surrounded by a vented region bridged by solid structures through which heat is conducted between the fluids. Precise, proprietary fabrication techniques make it possible to manufacture the vented regions and heat-conducting structures with very small dimensions to obtain a very large coefficient of heat transfer between the two fluids. A large heat-transfer coefficient favors compact design by making it possible to use a relatively small core for a given heat-transfer rate. Calculations and experiments have shown that in most respects, the fault-tolerant heat exchanger can be expected to equal or exceed the performance of the non-fault-tolerant heat exchanger that it is intended to supplant (see table). The only significant disadvantages are a slight weight penalty and a small decrease in the mass-specific heat transfer.

Quantitative Damage Detection and Sparse Sensor Array Optimization of Carbon Fiber Reinforced Resin Composite Laminates for Wind Turbine Blade Structural Health Monitoring

PubMed Central

Li, Xiang; Yang, Zhibo; Chen, Xuefeng

2014-01-01

The active structural health monitoring (SHM) approach for the complex composite laminate structures of wind turbine blades (WTBs), addresses the important and complicated problem of signal noise. After illustrating the wind energy industry's development perspectives and its crucial requirement for SHM, an improved redundant second generation wavelet transform (IRSGWT) pre-processing algorithm based on neighboring coefficients is introduced for feeble signal denoising. The method can avoid the drawbacks of conventional wavelet methods that lose information in transforms and the shortcomings of redundant second generation wavelet (RSGWT) denoising that can lead to error propagation. For large scale WTB composites, how to minimize the number of sensors while ensuring accuracy is also a key issue. A sparse sensor array optimization of composites for WTB applications is proposed that can reduce the number of transducers that must be used. Compared to a full sixteen transducer array, the optimized eight transducer configuration displays better accuracy in identifying the correct position of simulated damage (mass of load) on composite laminates with anisotropic characteristics than a non-optimized array. It can help to guarantee more flexible and qualified monitoring of the areas that more frequently suffer damage. The proposed methods are verified experimentally on specimens of carbon fiber reinforced resin composite laminates. PMID:24763210

Using the Job Burden-Capital Model of Occupational Stress to Predict Depression and Well-Being among Electronic Manufacturing Service Employees in China

PubMed Central

Wang, Chao; Li, Shuang; Li, Tao; Yu, Shanfa; Dai, Junming; Liu, Xiaoman; Zhu, Xiaojun; Ji, Yuqing; Wang, Jin

2016-01-01

Background: This study aimed to identify the association between occupational stress and depression-well-being by proposing a comprehensive and flexible job burden-capital model with its corresponding hypotheses. Methods: For this research, 1618 valid samples were gathered from the electronic manufacturing service industry in Hunan Province, China; self-rated questionnaires were administered to participants for data collection after obtaining their written consent. The proposed model was fitted and tested through structural equation model analysis. Results: Single-factor correlation analysis results indicated that coefficients between all items and dimensions had statistical significance. The final model demonstrated satisfactory global goodness of fit (CMIN/DF = 5.37, AGFI = 0.915, NNFI = 0.945, IFI = 0.952, RMSEA = 0.052). Both the measurement and structural models showed acceptable path loadings. Job burden and capital were directly associated with depression and well-being or indirectly related to them through personality. Multi-group structural equation model analyses indicated general applicability of the proposed model to basic features of such a population. Gender, marriage and education led to differences in the relation between occupational stress and health outcomes. Conclusions: The job burden-capital model of occupational stress-depression and well-being was found to be more systematic and comprehensive than previous models. PMID:27529267

Using the Job Burden-Capital Model of Occupational Stress to Predict Depression and Well-Being among Electronic Manufacturing Service Employees in China.

PubMed

Wang, Chao; Li, Shuang; Li, Tao; Yu, Shanfa; Dai, Junming; Liu, Xiaoman; Zhu, Xiaojun; Ji, Yuqing; Wang, Jin

2016-08-12

This study aimed to identify the association between occupational stress and depression-well-being by proposing a comprehensive and flexible job burden-capital model with its corresponding hypotheses. For this research, 1618 valid samples were gathered from the electronic manufacturing service industry in Hunan Province, China; self-rated questionnaires were administered to participants for data collection after obtaining their written consent. The proposed model was fitted and tested through structural equation model analysis. Single-factor correlation analysis results indicated that coefficients between all items and dimensions had statistical significance. The final model demonstrated satisfactory global goodness of fit (CMIN/DF = 5.37, AGFI = 0.915, NNFI = 0.945, IFI = 0.952, RMSEA = 0.052). Both the measurement and structural models showed acceptable path loadings. Job burden and capital were directly associated with depression and well-being or indirectly related to them through personality. Multi-group structural equation model analyses indicated general applicability of the proposed model to basic features of such a population. Gender, marriage and education led to differences in the relation between occupational stress and health outcomes. The job burden-capital model of occupational stress-depression and well-being was found to be more systematic and comprehensive than previous models.

Weibull crack density coefficient for polydimensional stress states

NASA Technical Reports Server (NTRS)

Gross, Bernard; Gyekenyesi, John P.

1989-01-01

A structural ceramic analysis and reliability evaluation code has recently been developed encompassing volume and surface flaw induced fracture, modeled by the two-parameter Weibull probability density function. A segment of the software involves computing the Weibull polydimensional stress state crack density coefficient from uniaxial stress experimental fracture data. The relationship of the polydimensional stress coefficient to the uniaxial stress coefficient is derived for a shear-insensitive material with a random surface flaw population.

A generic biokinetic model for carbon-14 labelled compounds

NASA Astrophysics Data System (ADS)

Manger, Ryan Paul

Carbon-14, a radioactive nuclide, is used in many industrial applications. Due to its wide range of uses in industry, many workers are at risk of accidental internal exposure to 14C. Being a low energy beta emitter, 14C is not a significant external radiation hazard, but the internal consequences posed by 14C are important, especially because of its long half life of 5730 years [46]. The current biokinetic model recommended by the International Commission on Radiological Protection (ICRP) is a conservative estimate of how radiocarbon is treated by the human body. The ICRP generic radiocarbon model consists of a single compartment representing the entire human body. This compartment has a biological half life of 40 days yielding an effective dose coefficient of 5.8x10-10 Sv B q-1 [44, 45, 49, 53, 54]. This overestimates the dose of all radiocarbon compounds that have been studied [96]. An improved model has been developed that includes and alimentary tract, a urinary bladder, CO2 model, and an "Other" compartment used to model systemic tissues. The model can be adapted to replicate any excretion curve and excretion pattern. In addition, the effective dose coefficient produced by the updated model is near the mean effective dose coefficient of carbon compounds that have been considered in this research. The major areas of improvement are: more anatomically significant, a less conservative dose coefficient, and the ability to manipulate the model for known excretion data. Due to the wide variety of carbon compounds, it is suggested that specific biokinetic models be implemented for known radiocarbon substances. If the source of radiocarbon is dietary, then the physiologically based model proposed by Whillans [102] that splits all ingested radiocarbon compounds into carbohydrates, fats, and proteins should be used.

Structural studies of liquid Co–Sn alloys

PubMed Central

Yakymovych, A.; Shtablavyi, I.; Mudry, S.

2014-01-01

An analysis of the structure features of liquid Co–Sn alloys has been performed by means of X-ray diffraction method, viscosity coefficient analysis and computer simulation method. The X-ray diffraction investigations were carried out over a wide concentration range at the temperature 1473 K. It was found that the structure of these alloys can be described in the frame of independent X-ray scattering model. The viscosity coefficient was calculated by an excess entropy scaling and compared with experimental data. PMID:25328282

Electron transport in electrically biased inverse parabolic double-barrier structure

NASA Astrophysics Data System (ADS)

M, Bati; S, Sakiroglu; I, Sokmen

2016-05-01

A theoretical study of resonant tunneling is carried out for an inverse parabolic double-barrier structure subjected to an external electric field. Tunneling transmission coefficient and density of states are analyzed by using the non-equilibrium Green’s function approach based on the finite difference method. It is found that the resonant peak of the transmission coefficient, being unity for a symmetrical case, reduces under the applied electric field and depends strongly on the variation of the structure parameters.

Minimum spanning tree filtering of correlations for varying time scales and size of fluctuations

NASA Astrophysics Data System (ADS)

Kwapień, Jarosław; Oświecimka, Paweł; Forczek, Marcin; DroŻdŻ, Stanisław

2017-05-01

Based on a recently proposed q -dependent detrended cross-correlation coefficient, ρq [J. Kwapień, P. Oświęcimka, and S. Drożdż, Phys. Rev. E 92, 052815 (2015), 10.1103/PhysRevE.92.052815], we generalize the concept of the minimum spanning tree (MST) by introducing a family of q -dependent minimum spanning trees (q MST s ) that are selective to cross-correlations between different fluctuation amplitudes and different time scales of multivariate data. They inherit this ability directly from the coefficients ρq, which are processed here to construct a distance matrix being the input to the MST-constructing Kruskal's algorithm. The conventional MST with detrending corresponds in this context to q =2 . In order to illustrate their performance, we apply the q MSTs to sample empirical data from the American stock market and discuss the results. We show that the q MST graphs can complement ρq in disentangling "hidden" correlations that cannot be observed in the MST graphs based on ρDCCA, and therefore, they can be useful in many areas where the multivariate cross-correlations are of interest. As an example, we apply this method to empirical data from the stock market and show that by constructing the q MSTs for a spectrum of q values we obtain more information about the correlation structure of the data than by using q =2 only. More specifically, we show that two sets of signals that differ from each other statistically can give comparable trees for q =2 , while only by using the trees for q ≠2 do we become able to distinguish between these sets. We also show that a family of q MSTs for a range of q expresses the diversity of correlations in a manner resembling the multifractal analysis, where one computes a spectrum of the generalized fractal dimensions, the generalized Hurst exponents, or the multifractal singularity spectra: the more diverse the correlations are, the more variable the tree topology is for different q 's. As regards the correlation structure of the stock market, our analysis exhibits that the stocks belonging to the same or similar industrial sectors are correlated via the fluctuations of moderate amplitudes, while the largest fluctuations often happen to synchronize in those stocks that do not necessarily belong to the same industry.

Analytical equation for outflow along the flow in a perforated fluid distribution pipe

PubMed Central

Liu, Huanfang; Lv, Hongxing; Jin, Jin

2017-01-01

Perforated fluid distribution pipes have been widely used in agriculture, water supply and drainage, ventilation, the chemical industry, and other sectors. The momentum equation for variable mass flow with a variable exchange coefficient and variable friction coefficient was developed by using the momentum conservation method under the condition of a certain slope. The change laws of the variable momentum exchange coefficient and the variable resistance coefficient along the flow were analyzed, and the function of the momentum exchange coefficient was given. According to the velocity distribution of the power function, the momentum equation of variable mass flow was solved for different Reynolds numbers. The analytical solution contains components of pressure, gravity, friction and momentum and reflects the influence of various factors on the pressure distribution along the perforated pipe. The calculated results of the analytical solution were compared with the experimental values of the study by Jin et al. 1984 and Wang et al. 2001 with the mean errors 8.2%, 3.8% and 2.7%, and showed that the analytical solution of the variable mass momentum equation was qualitatively and quantitatively consistent with the experimental results. PMID:29065112

Future of the world's automobile industry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kagawa, T.

1989-03-01

The author feels that the Japanese automobile industry is approaching a turning point. But it is not enough to refer only to the changing structure of the Japanese automobile industry when similar structural changes are taking place on a worldwide scale. Therefore he first comments on the current state of the automobile industry of the world, and then reviews the reasons for the gap between automobile production and demand and the historical background of this phenomenon. Then, finally, he discusses the current progress of and future challenges in the structural adjustment of the global automobile industry. He notes the verymore » close relation of the battery industry to the automobile industry, and hopes the former will prosper hand in hand with the latter. 6 tables.« less

Probabilistic estimation of splitting coefficients of normal modes of the Earth, and their uncertainties, using an autoregressive technique

NASA Astrophysics Data System (ADS)

Pachhai, S.; Masters, G.; Laske, G.

2017-12-01

Earth's normal-mode spectra are crucial to studying the long wavelength structure of the Earth. Such observations have been used extensively to estimate "splitting coefficients" which, in turn, can be used to determine the three-dimensional velocity and density structure. Most past studies apply a non-linear iterative inversion to estimate the splitting coefficients which requires that the earthquake source is known. However, it is challenging to know the source details, particularly for big events as used in normal-mode analyses. Additionally, the final solution of the non-linear inversion can depend on the choice of damping parameter and starting model. To circumvent the need to know the source, a two-step linear inversion has been developed and successfully applied to many mantle and core sensitive modes. The first step takes combinations of the data from a single event to produce spectra known as "receiver strips". The autoregressive nature of the receiver strips can then be used to estimate the structure coefficients without the need to know the source. Based on this approach, we recently employed a neighborhood algorithm to measure the splitting coefficients for an isolated inner-core sensitive mode (13S2). This approach explores the parameter space efficiently without any need of regularization and finds the structure coefficients which best fit the observed strips. Here, we implement a Bayesian approach to data collected for earthquakes from early 2000 and more recent. This approach combines the data (through likelihood) and prior information to provide rigorous parameter values and their uncertainties for both isolated and coupled modes. The likelihood function is derived from the inferred errors of the receiver strips which allows us to retrieve proper uncertainties. Finally, we apply model selection criteria that balance the trade-offs between fit (likelihood) and model complexity to investigate the degree and type of structure (elastic and anelastic) required to explain the data.

First-principles simulation on Seebeck coefficient in silicon nanowires

NASA Astrophysics Data System (ADS)

Nakamura, Koichi

2017-06-01

The Seebeck coefficients of silicon nanowires (SiNWs) were simulated on the basis of first-principles calculation using various atomistic structure models. The electronic band structures of fully hydrogen-terminated SiNW models give the correct image of quantum mechanical confinement from bulk silicon to SiNW for each axial direction, and the change in the density of states by dimensional reduction to SiNW enhances the thermoelectric performance in terms of the Seebeck coefficient, compared with those of bulk silicon and silicon nanosheets. The uniaxial tensile strain for the SiNW models does not strongly affect the Seebeck coefficient even for the SiNW system with giant piezoresistivity. In contrast, dangling bonds on a wire wall sharply reduce the Seebeck coefficient of SiNW and totally degrade thermoelectric performance from the viewpoint of the power factor. The exclusion of dangling bonds is a key element for the design and application of high-performance thermoelectric nanowires of semiconducting materials.

Laser Cladding of γ-TiAl Intermetallic Alloy on Titanium Alloy Substrates

NASA Astrophysics Data System (ADS)

Maliutina, Iuliia Nikolaevna; Si-Mohand, Hocine; Piolet, Romain; Missemer, Florent; Popelyukh, Albert Igorevich; Belousova, Natalya Sergeevna; Bertrand, Philippe

2016-01-01

The enhancement of titanium and titanium alloy's tribological properties is of major interest in many applications such as the aerospace and automotive industry. Therefore, the current research paper investigates the laser cladding of Ti48Al2Cr2Nb powder onto Ti6242 titanium alloy substrates. The work was carried out in two steps. First, the optimal deposition parameters were defined using the so-called "combined parameters," i.e., the specific energy E specific and powder density G. Thus, the results show that those combined parameters have a significant influence on the geometry, microstructure, and microhardness of titanium aluminide-formed tracks. Then, the formation of dense, homogeneous, and defect-free coatings based on optimal parameters has been investigated. Optical and scanning electron microscopy techniques as well as energy-dispersive spectroscopy and X-ray diffraction analyses have shown that a duplex structure consisting of γ-TiAl and α 2-Ti3Al phases was obtained in the coatings during laser cladding. Moreover, it was shown that produced coatings exhibit higher values of microhardness (477 ± 9 Hv0.3) and wear resistance (average friction coefficient is 0.31 and volume of worn material is 5 mm3 after 400 m) compared to those obtained with bare titanium alloy substrates (353 Hv0.3, average friction coefficient is 0.57 and a volume of worn material after 400 m is 35 mm3).

78 FR 63220 - Guidance for Industry on Acute Bacterial Skin and Skin Structure Infections: Developing Drugs for...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-23

...] Guidance for Industry on Acute Bacterial Skin and Skin Structure Infections: Developing Drugs for Treatment... Administration (FDA) is announcing the availability of a guidance for industry entitled ``Acute Bacterial Skin and Skin Structure Infections: Developing Drugs for Treatment.'' The purpose of this guidance is to...

Calibration test of the temperature and strain sensitivity coefficient in regional reference grating method

NASA Astrophysics Data System (ADS)

Wu, Jing; Huang, Junbing; Wu, Hanping; Gu, Hongcan; Tang, Bo

2014-12-01

In order to verify the validity of the regional reference grating method in solve the strain/temperature cross sensitive problem in the actual ship structural health monitoring system, and to meet the requirements of engineering, for the sensitivity coefficients of regional reference grating method, national standard measurement equipment is used to calibrate the temperature sensitivity coefficient of selected FBG temperature sensor and strain sensitivity coefficient of FBG strain sensor in this modal. And the thermal expansion sensitivity coefficient of the steel for ships is calibrated with water bath method. The calibration results show that the temperature sensitivity coefficient of FBG temperature sensor is 28.16pm/°C within -10~30°C, and its linearity is greater than 0.999, the strain sensitivity coefficient of FBG strain sensor is 1.32pm/μɛ within -2900~2900μɛ whose linearity is almost to 1, the thermal expansion sensitivity coefficient of the steel for ships is 23.438pm/°C within 30~90°C, and its linearity is greater than 0.998. Finally, the calibration parameters are used in the actual ship structure health monitoring system for temperature compensation. The results show that the effect of temperature compensation is good, and the calibration parameters meet the engineering requirements, which provide an important reference for fiber Bragg grating sensor is widely used in engineering.

Flocculation kinetics and aggregate structure of kaolinite mixtures in laminar tube flow.

PubMed

Vaezi G, Farid; Sanders, R Sean; Masliyah, Jacob H

2011-03-01

Flocculation is commonly used in various solid-liquid separation processes in chemical and mineral industries to separate desired products or to treat waste streams. This paper presents an experimental technique to study flocculation processes in laminar tube flow. This approach allows for more realistic estimation of the shear rate to which an aggregate is exposed, as compared to more complicated shear fields (e.g. stirred tanks). A direct sampling method is used to minimize the effect of sampling on the aggregate structure. A combination of aggregate settling velocity and image analysis was used to quantify the structure of the aggregate. Aggregate size, density, and fractal dimension were found to be the most important aggregate structural parameters. The two methods used to determine aggregate fractal dimension were in good agreement. The effects of advective flow through an aggregate's porous structure and transition-regime drag coefficient on the evaluation of aggregate density were considered. The technique was applied to investigate the flocculation kinetics and the evolution of the aggregate structure of kaolin particles with an anionic flocculant under conditions similar to those of oil sands fine tailings. Aggregates were formed using a well controlled two-stage aggregation process. Detailed statistical analysis was performed to investigate the establishment of dynamic equilibrium condition in terms of aggregate size and density evolution. An equilibrium steady state condition was obtained within 90 s of the start of flocculation; after which no further change in aggregate structure was observed. Although longer flocculation times inside the shear field could conceivably cause aggregate structure conformation, statistical analysis indicated that this did not occur for the studied conditions. The results show that the technique and experimental conditions employed here produce aggregates having a well-defined, reproducible structure. Copyright © 2011. Published by Elsevier Inc.

Highlighting material structure with transmission electron diffraction correlation coefficient maps.

PubMed

Kiss, Ákos K; Rauch, Edgar F; Lábár, János L

2016-04-01

Correlation coefficient maps are constructed by computing the differences between neighboring diffraction patterns collected in a transmission electron microscope in scanning mode. The maps are shown to highlight material structural features like grain boundaries, second phase particles or dislocations. The inclination of the inner crystal interfaces are directly deduced from the resulting contrast. Copyright © 2016 Elsevier B.V. All rights reserved.

Market Structure, Financial Dependence and Industrial Growth: Evidence from the Banking Industry in Emerging Asian Economies

PubMed Central

Khan, Habib Hussain; Ahmad, Rubi Binit; Gee, Chan Sok

2016-01-01

In this study, we examine the role of market structure for growth in financially dependent industries from 10 emerging Asian economies over the period of 1995–2011. Our approach departs from existing studies in that we apply four alternative measures of market structure based on structural and non-structural approaches and compare their outcomes. Results indicate that higher bank concentration may slow down the growth of financially dependent industries. Bank competition on the other hand, allows financially dependent industries to grow faster. These findings are consistent across a number of sensitivity checks such as alternative measures of financial dependence, institutional factors (including property rights, quality of accounting standards and bank ownership), and endogeneity consideration. In sum, our study suggests that financially dependent industries grow more in more competitive/less concentrated banking systems. Therefore, regulatory authorities need to be careful while pursuing a consolidation policy for banking sector in emerging Asian economies. PMID:27490847

Analysis of inter-country input-output table based on bibliographic coupling network: How industrial sectors on the GVC compete for production resources

NASA Astrophysics Data System (ADS)

Guan, Jun; Xu, Xiaoyu; Xing, Lizhi

2018-03-01

The input-output table is comprehensive and detailed in describing national economic systems with abundance of economic relationships depicting information of supply and demand among industrial sectors. This paper focuses on how to quantify the degree of competition on the global value chain (GVC) from the perspective of econophysics. Global Industrial Strongest Relevant Network models are established by extracting the strongest and most immediate industrial relevance in the global economic system with inter-country input-output (ICIO) tables and then have them transformed into Global Industrial Resource Competition Network models to analyze the competitive relationships based on bibliographic coupling approach. Three indicators well suited for the weighted and undirected networks with self-loops are introduced here, including unit weight for competitive power, disparity in the weight for competitive amplitude and weighted clustering coefficient for competitive intensity. Finally, these models and indicators were further applied empirically to analyze the function of industrial sectors on the basis of the latest World Input-Output Database (WIOD) in order to reveal inter-sector competitive status during the economic globalization.

Relation between the structural parameters of metallic glasses at the onset crystallization temperatures and threshold values of the effective diffusion coefficients

NASA Astrophysics Data System (ADS)

Tkatch, V. I.; Svyrydova, K. A.; Vasiliev, S. V.; Kovalenko, O. V.

2017-08-01

Using the results of differential scanning calorimetry and X-ray diffractometry, an analysis has been carried out of the initial stages of the eutectic and primary mechanisms of crystallization of a series of metallic glasses based on Fe and Al with the established temperature dependences of the effective diffusion coefficients. Analytical relationships, which relate the volume density of crystallites formed in the glasses at the temperatures of the onset of crystallization with the values of the effective diffusion coefficients at these temperatures have been proposed. It has been established that, in the glasses, the crystallization of which begins at the lower boundary of the threshold values of the effective diffusion coefficients ( 10-20 m2/s), structures are formed with the volume density of crystallites on the order of 1023-1024 m-3 and, at the upper boundary (10-18 m2/s), of the order of 1018 and 1020 m-3 in the glasses that are crystallized via the eutectic and primary mechanisms, respectively. Good agreement between the calculated and experimental estimates indicates that the threshold values of the effective diffusion coefficients are the main factors that determine the structure of glasses at the initial stages of crystallization.

Sensitivity Analysis of Nuclide Importance to One-Group Neutron Cross Sections

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sekimoto, Hiroshi; Nemoto, Atsushi; Yoshimura, Yoshikane

The importance of nuclides is useful when investigating nuclide characteristics in a given neutron spectrum. However, it is derived using one-group microscopic cross sections, which may contain large errors or uncertainties. The sensitivity coefficient shows the effect of these errors or uncertainties on the importance.The equations for calculating sensitivity coefficients of importance to one-group nuclear constants are derived using the perturbation method. Numerical values are also evaluated for some important cases for fast and thermal reactor systems.Many characteristics of the sensitivity coefficients are derived from the derived equations and numerical results. The matrix of sensitivity coefficients seems diagonally dominant. However,more » it is not always satisfied in a detailed structure. The detailed structure of the matrix and the characteristics of coefficients are given.By using the obtained sensitivity coefficients, some demonstration calculations have been performed. The effects of error and uncertainty of nuclear data and of the change of one-group cross-section input caused by fuel design changes through the neutron spectrum are investigated. These calculations show that the sensitivity coefficient is useful when evaluating error or uncertainty of nuclide importance caused by the cross-section data error or uncertainty and when checking effectiveness of fuel cell or core design change for improving neutron economy.« less

Universal thermoelectric unit

NASA Astrophysics Data System (ADS)

Fedorov, M. I.; Engalychev, A. E.; Zaitsev, V. K.; Kaliazin, A. E.; Solomkin, F. Yu.

1994-08-01

The problems of energy supply of low power electric devices very often can be solved with thermoelectric generator even with low coefficient of performance, when other electric energy sources are not convenient. The problems of thermoelectric and construction choice for such generators are discussed in the paper. A series of domestic thermoelectric generators was designed by the authors. The work is based on designing an universal thermoelectric unit—a battery which consist of ten thermoelements. The coefficient of performance of the unit is about 4%. Any thermoelectric generator can be made as a combination of these units. Principal opportunity of production such thermoelectric generators on industrial scale was proved.

Self-Normalized Photoacoustic Technique for the Quantitative Analysis of Paper Pigments

NASA Astrophysics Data System (ADS)

Balderas-López, J. A.; Gómez y Gómez, Y. M.; Bautista-Ramírez, M. E.; Pescador-Rojas, J. A.; Martínez-Pérez, L.; Lomelí-Mejía, P. A.

2018-03-01

A self-normalized photoacoustic technique was applied for quantitative analysis of pigments embedded in solids. Paper samples (filter paper, Whatman No. 1), attached with the pigment: Direct Fast Turquoise Blue GL, were used for this study. This pigment is a blue dye commonly used in industry to dye paper and other fabrics. The optical absorption coefficient, at a wavelength of 660 nm, was measured for this pigment at various concentrations in the paper substrate. It was shown that Beer-Lambert model for light absorption applies well for pigments in solid substrates and optical absorption coefficients as large as 220 cm^{-1} can be measured with this photoacoustic technique.

Diffusivity of nitrous oxide in N-methyldiethanolamine + diethanolamine + water

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rinker, E.B.; Russell, J.W.; Tamimi, A.

1995-05-01

The tertiary amine N-methyldiethanolamine and the secondary amine diethanolamine are commonly used in the gas-treating industry as chemical solvents for the removal of acid gases such as CO{sub 2} and H{sub 2}S. The diffusion coefficients for nitrous oxide in aqueous solutions consisting of N-methyldiethanolamine (MDEA) and diethanolamine (DEA) were measured over the temperature range 293--353 K for a total amine concentration of 50 mass % and for the mass ratio of DEA to MDEA varying from 0.0441 to 0.588. The experimental diffusion coefficients were found to be relatively insensitive to the mass ratio of amines.

Investigation of the Effect of the Tortuous Pore Structure on Water Diffusion through a Polymer Film Using Lattice Boltzmann Simulations.

PubMed

Gebäck, Tobias; Marucci, Mariagrazia; Boissier, Catherine; Arnehed, Johan; Heintz, Alexei

2015-04-23

Understanding how the pore structure influences the mass transport through a porous material is important in several applications, not the least in the design of polymer film coatings intended to control drug release. In this study, a polymer film made of ethyl cellulose and hydroxypropyl cellulose was investigated. The 3D structure of the films was first experimentally characterized using confocal laser scanning microscopy data and then mathematically reconstructed for the whole film thickness. Lattice Boltzmann simulations were performed to compute the effective diffusion coefficient of water in the film and the results were compared to experimental data. The local porosities and pore sizes were also analyzed to determine how the properties of the internal film structure affect the water effective diffusion coefficient. The results show that the top part of the film has lower porosity, lower pore size, and lower connectivity, which results in a much lower effective diffusion coefficient in this part, largely determining the diffusion rate through the entire film. Furthermore, the local effective diffusion coefficients were not proportional to the local film porosity, indicating that the results cannot be explained by a single tortuosity factor. In summary, the proposed methodology of combining microscopy data, mass transport simulations, and pore space analysis can give valuable insights on how the film structure affects the mass transport through the film.

NMR investigation of water diffusion in different biofilm structures.

PubMed

Herrling, Maria P; Weisbrodt, Jessica; Kirkland, Catherine M; Williamson, Nathan H; Lackner, Susanne; Codd, Sarah L; Seymour, Joseph D; Guthausen, Gisela; Horn, Harald

2017-12-01

Mass transfer in biofilms is determined by diffusion. Different mostly invasive approaches have been used to measure diffusion coefficients in biofilms, however, data on heterogeneous biomass under realistic conditions is still missing. To non-invasively elucidate fluid-structure interactions in complex multispecies biofilms pulsed field gradient-nuclear magnetic resonance (PFG-NMR) was applied to measure the water diffusion in five different types of biomass aggregates: one type of sludge flocs, two types of biofilm, and two types of granules. Data analysis is an important issue when measuring heterogeneous systems and is shown to significantly influence the interpretation and understanding of water diffusion. With respect to numerical reproducibility and physico-chemical interpretation, different data processing methods were explored: (bi)-exponential data analysis and the Γ distribution model. Furthermore, the diffusion coefficient distribution in relation to relaxation was studied by D-T 2 maps obtained by 2D inverse Laplace transform (2D ILT). The results show that the effective diffusion coefficients for all biofilm samples ranged from 0.36 to 0.96 relative to that of water. NMR diffusion was linked to biofilm structure (e.g., biomass density, organic and inorganic matter) as observed by magnetic resonance imaging and to traditional biofilm parameters: diffusion was most restricted in granules with compact structures, and fast diffusion was found in heterotrophic biofilms with fluffy structures. The effective diffusion coefficients in the biomass were found to be broadly distributed because of internal biomass heterogeneities, such as gas bubbles, precipitates, and locally changing biofilm densities. Thus, estimations based on biofilm bulk properties in multispecies systems can be overestimated and mean diffusion coefficients might not be sufficiently informative to describe mass transport in biofilms and the near bulk. © 2017 Wiley Periodicals, Inc.

Introduction and application of the multiscale coefficient of variation analysis.

PubMed

Abney, Drew H; Kello, Christopher T; Balasubramaniam, Ramesh

2017-10-01

Quantifying how patterns of behavior relate across multiple levels of measurement typically requires long time series for reliable parameter estimation. We describe a novel analysis that estimates patterns of variability across multiple scales of analysis suitable for time series of short duration. The multiscale coefficient of variation (MSCV) measures the distance between local coefficient of variation estimates within particular time windows and the overall coefficient of variation across all time samples. We first describe the MSCV analysis and provide an example analytical protocol with corresponding MATLAB implementation and code. Next, we present a simulation study testing the new analysis using time series generated by ARFIMA models that span white noise, short-term and long-term correlations. The MSCV analysis was observed to be sensitive to specific parameters of ARFIMA models varying in the type of temporal structure and time series length. We then apply the MSCV analysis to short time series of speech phrases and musical themes to show commonalities in multiscale structure. The simulation and application studies provide evidence that the MSCV analysis can discriminate between time series varying in multiscale structure and length.

Expanded Study on the accumulation effect of tourism under the constraint of structure

NASA Astrophysics Data System (ADS)

Wang, Qiang; Yang, Zhenzhi; Huang, Lu

2017-05-01

There is a mutual influence between departmental structure and accumulation and growth. Therefore, the accumulation and growth of the tourism industry will be subject to certain restrictions on the industrial structure, and, conversely, it will have an impact on the existing industrial structure. Li Jingyi reported special research in the paper called "Research on tourism growth based on structural constraints" about the relationship between the growth of tourism and the existing industrial structure. It pointed out the specific interdependence between tourism and other economic sectors in terms of accumulation and growth. However, the research of Li Jingyi is based on the trichotomy of social product value. It is too abstract, while the study is understandable in theory. In practice, it is difficult to use the model of the paper to deal with specific problems. Therefore, how to improve the industry association model in the paper of Li and make it more in line with the actual situation becomes our concern. In this paper, the author hopes to improve the model of Li's paper by simplifying the decomposition of social product value. At the same time, it makes a further study on accumulation elasticity and growth elasticity. On this basis, some suggestions are put forward to guide the development of other industries based on the tourism industry.

Influence of structure properties on protein-protein interactions-QSAR modeling of changes in diffusion coefficients.

PubMed

Bauer, Katharina Christin; Hämmerling, Frank; Kittelmann, Jörg; Dürr, Cathrin; Görlich, Fabian; Hubbuch, Jürgen

2017-04-01

Information about protein-protein interactions provides valuable knowledge about the phase behavior of protein solutions during the biopharmaceutical production process. Up to date it is possible to capture their overall impact by an experimentally determined potential of mean force. For the description of this potential, the second virial coefficient B22, the diffusion interaction parameter kD, the storage modulus G', or the diffusion coefficient D is applied. In silico methods do not only have the potential to predict these parameters, but also to provide deeper understanding of the molecular origin of the protein-protein interactions by correlating the data to the protein's three-dimensional structure. This methodology furthermore allows a lower sample consumption and less experimental effort. Of all in silico methods, QSAR modeling, which correlates the properties of the molecule's structure with the experimental behavior, seems to be particularly suitable for this purpose. To verify this, the study reported here dealt with the determination of a QSAR model for the diffusion coefficient of proteins. This model consisted of diffusion coefficients for six different model proteins at various pH values and NaCl concentrations. The generated QSAR model showed a good correlation between experimental and predicted data with a coefficient of determination R2 = 0.9 and a good predictability for an external test set with R2 = 0.91. The information about the properties affecting protein-protein interactions present in solution was in agreement with experiment and theory. Furthermore, the model was able to give a more detailed picture of the protein properties influencing the diffusion coefficient and the acting protein-protein interactions. Biotechnol. Bioeng. 2017;114: 821-831. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

American export control, technology spillover and innovation of Chinese pharmaceutical Industry.

PubMed

Hui, Jiang

2017-05-01

This paper was aimed to analyze whether the U.S. strict export control to China affects the technological innovation of Chinese pharmaceutical industry. This paper selected the data of technological innovation and the expenditure of high and new technology adoption in China's pharmaceutical industry from 1995 to 2014, created panel regression model to study the impact of export controls on technology spillovers and the impact of technology spillovers on innovation capacity. The results show that US export control has a significant impact on technology spillovers, but foreign technology spillovers have no significant impact on the innovation of Chinese pharmaceutical industry. Although the US export control prevented foreign technology spillovers to China, but indirectly stimulated the domestic technology spillovers to pharmaceutical manufacturing industry in China. Statistical analysis show that the correlation coefficient between innovation capacity and expenditure for high technology adoption is not significant, but the expenditure of purchasing domestic technical is essential to pharmaceutical innovation. This study shows that US export control indirectly, not directly, affected the technological innovation of China's pharmaceutical industry, affected the allocation of innovative resources, but failed to prevent the technological progress and competitiveness improvement of Chinese pharmaceutical industry.

Potential utilization of guar gum industrial waste in vermicompost production.

PubMed

Suthar, Surendra

2006-12-01

Recycling of guar gum industrial waste through vermitechnology was studied under laboratory conditions by using composting earthworm Perionyx excavatus (Perrier). Three different combination of guar gum industrial waste namely guar gum industrial waste:cow dung:saw dust in 40:30:30 ratio (T1), guar gum industrial waste:cow dung:saw dust in 60:20:20 ratio (T2), and guar gum industrial waste:cow dung:saw dust in 75:15:10 ratio (T3) were used for vermicomposting experiments. Chemical changes during vermicomposting were measured and comparatively T2 showed great increase (from its initial level) for total N (25.4%), phosphorus (72.8%) and potassium (20.9%) than the other treatments. T2 also showed higher vermicomposting coefficient (VC), higher mean biomass for P. excavatus (146.68 mg) and higher cocoon production (about 21.9% and 645.5% more than the T1 and T3, respectively). Maximum earthworm mortality during vermicomposting was recorded with T3 treatment while zero mortality was recorded for T2 treatment after 150 days. Overall, T2 treatment appeared to be an ideal combination for enhancing maximum biopotential of earthworms to management guar gum industrial waste as well as for earthworm biomass and cocoon production.

US hardwood lumber consumption and international trade from 1991 to 2014

Treesearch

William G. Luppold; Matt Bumgardner

2016-01-01

Apparent US hardwood lumber consumption (developed from production, import, and export data) was contrasted with estimated consumption based on employment data and lumber utilization coefficients. The two methods of measuring domestic consumption provided similar results, but the use of employment data allowed for a comparison of appearance lumber vs industrial lumber...

Numerical simulation of a bubble rising in an environment consisting of Xanthan gum

NASA Astrophysics Data System (ADS)

Aguirre, Víctor A.; Castillo, Byron A.; Narvaez, Christian P.

2017-09-01

An improved numerical algorithm for front tracking method is developed to simulate a bubble rising in viscous liquid. In the new numerical algorithm, volume correction is introduced to conserve the bubble volume while tracking the bubble's rising and deforming. Volume flux conservation is adopted to solve the Navier-Stokes equation for fluid flow using finite volume method. Non-Newtonian fluids are widely used in industry such as feed and energy industries. In this research we used Xanthan gum which is a microbiological polysaccharide. In order to obtain the properties of the Xanthan gum, such as viscosity, storage and loss modulus, shear rate, etc., it was necessary to do an amplitude sweep and steady flow test in a rheometer with a concentric cylinder as geometry. Based on the data given and using a numerical regression, the coefficients required by Giesekus model are obtained. With these coefficients, it is possible to simulate the comportment of the fluid by the use of the developed algorithm. Once the data given by OpenFOAM is acquired, it is compared with the experimental data.

Ultrasonic Non Linearity Characterization of the Stainless Steel Wire Reinforced Aluminium Composite

NASA Astrophysics Data System (ADS)

Kim, C. S.; Park, T. S.; Park, I. K.; Hyun, C. Y.

2009-03-01

The effectiveness of the ultrasonic nonlinearity measurement for nearly closed cracks was demonstrated for hot pressing and extrusion of stainless steel 304 short wire reinforced aluminum composite. Aluminum based composites show considerable potential in the aerospace industry and the automotive industry due to their high specific strength and low thermal expansion coefficient. The ultrasonic nonlinearity (β/β0) increased with the volume fraction of SSF and aging heat treatment because of the generation of microvoids resulted from localized SSF and matrix precipitation. This study demonstrates the potential for characterization of reinforced composite materials fabricated by the powder metallurgy technique.

Respirable particulate monitoring with remote sensors. (Public health ecology: Air pollution)

NASA Technical Reports Server (NTRS)

Severs, R. K.

1974-01-01

The feasibility of monitoring atmospheric aerosols in the respirable range from air or space platforms was studied. Secondary reflectance targets were located in the industrial area and near Galveston Bay. Multichannel remote sensor data were utilized to calculate the aerosol extinction coefficient and thus determine the aerosol size distribution. Houston Texas air sampling network high volume data were utilized to generate computer isopleth maps of suspended particulates and to establish the mass loading of the atmosphere. In addition, a five channel nephelometer and a multistage particulate air sampler were used to collect data. The extinction coefficient determined from remote sensor data proved more representative of wide areal phenomena than that calculated from on site measurements. It was also demonstrated that a significant reduction in the standard deviation of the extinction coefficient could be achieved by reducing the bandwidths used in remote sensor.

The Delicate Analysis of Short-Term Load Forecasting

NASA Astrophysics Data System (ADS)

Song, Changwei; Zheng, Yuan

2017-05-01

This paper proposes a new method for short-term load forecasting based on the similar day method, correlation coefficient and Fast Fourier Transform (FFT) to achieve the precision analysis of load variation from three aspects (typical day, correlation coefficient, spectral analysis) and three dimensions (time dimension, industry dimensions, the main factors influencing the load characteristic such as national policies, regional economic, holidays, electricity and so on). First, the branch algorithm one-class-SVM is adopted to selection the typical day. Second, correlation coefficient method is used to obtain the direction and strength of the linear relationship between two random variables, which can reflect the influence caused by the customer macro policy and the scale of production to the electricity price. Third, Fourier transform residual error correction model is proposed to reflect the nature of load extracting from the residual error. Finally, simulation result indicates the validity and engineering practicability of the proposed method.

Analysis of Energy Industry Upgrading in Northeast China

NASA Astrophysics Data System (ADS)

Liu, Xiao-jing; Ji, Yu-liang; Guan, Bai-feng; Jing, Xin

2018-02-01

Promoting regional economic growth and realizing the transformation of the mode of economic growth are in industrial upgrading essence The product is a carrier that represents a series of links of production, management and marketing behind the enterprise, and is a comprehensive reflection of the knowledge and ability of a country or region. Based on the industrial spatial structure, this paper visualizes the industrial space in Northeast China from 2005 to 2015, analyzes the comparative advantages of the energy industry in Northeast China, and examines the status quo of the upgrade of the energy industry according to the industrial upgrading status. Based on the industrial spatial structure, Industry intensity in the industrial space, put forward the future direction of the energy industry upgrade and upgrade path.

Three-phase inductive-coupled structures for contactless PHEV charging system

NASA Astrophysics Data System (ADS)

Lee, Jia-You; Shen, Hung-Yu; Li, Cheng-Bin

2016-07-01

In this article, a new-type three-phase inductive-coupled structure is proposed for the contactless plug-in hybrid electric vehicle (PHEV) charging system regarding with SAE J-1773. Four possible three-phase core structures are presented and subsequently investigated by the finite element analysis. To study the correlation between the core geometric parameter and the coupling coefficient, the magnetic equivalent circuit model of each structure is also established. In accordance with the simulation results, the low reluctance and the sharing of flux path in the core material are achieved by the proposed inductive-coupled structure with an arc-shape and three-phase symmetrical core material. It results in a compensation of the magnetic flux between each phase and a continuous flow of the output power in the inductive-coupled structure. Higher coupling coefficient between inductive-coupled structures is achieved. A comparison of coupling coefficient, mutual inductance, and self-inductance between theoretical and measured results is also performed to verify the proposed model. A 1 kW laboratory scale prototype of the contactless PHEV charging system with the proposed arc-shape three-phase inductive-coupled structure is implemented and tested. An overall system efficiency of 88% is measured when two series lithium iron phosphate battery packs of 25.6 V/8.4 Ah are charged.

Application of design sensitivity analysis for greater improvement on machine structural dynamics

NASA Technical Reports Server (NTRS)

Yoshimura, Masataka

1987-01-01

Methodologies are presented for greatly improving machine structural dynamics by using design sensitivity analyses and evaluative parameters. First, design sensitivity coefficients and evaluative parameters of structural dynamics are described. Next, the relations between the design sensitivity coefficients and the evaluative parameters are clarified. Then, design improvement procedures of structural dynamics are proposed for the following three cases: (1) addition of elastic structural members, (2) addition of mass elements, and (3) substantial charges of joint design variables. Cases (1) and (2) correspond to the changes of the initial framework or configuration, and (3) corresponds to the alteration of poor initial design variables. Finally, numerical examples are given for demonstrating the availability of the methods proposed.

Rotational characterization of methyl methacrylate: Internal dynamics and structure determination

NASA Astrophysics Data System (ADS)

Herbers, Sven; Wachsmuth, Dennis; Obenchain, Daniel A.; Grabow, Jens-Uwe

2018-01-01

Rotational constants, Watson's S centrifugal distortion coefficients, and internal rotation parameters of the two most stable conformers of methyl methacrylate were retrieved from the microwave spectrum. Splittings of rotational energy levels were caused by two non equivalent methyl tops. Constraining the centrifugal distortion coefficients and internal rotation parameters to the values of the main isotopologues, the rotational constants of all single substituted 13C and 18O isotopologues were determined. From these rotational constants the substitution structures and semi-empirical zero point structures of both conformers were precisely determined.

Modelling the attenuation in the ATHENA finite elements code for the ultrasonic testing of austenitic stainless steel welds.

PubMed

Chassignole, B; Duwig, V; Ploix, M-A; Guy, P; El Guerjouma, R

2009-12-01

Multipass welds made in austenitic stainless steel, in the primary circuit of nuclear power plants with pressurized water reactors, are characterized by an anisotropic and heterogeneous structure that disturbs the ultrasonic propagation and makes ultrasonic non-destructive testing difficult. The ATHENA 2D finite element simulation code was developed to help understand the various physical phenomena at play. In this paper, we shall describe the attenuation model implemented in this code to give an account of wave scattering phenomenon through polycrystalline materials. This model is in particular based on the optimization of two tensors that characterize this material on the basis of experimental values of ultrasonic velocities attenuation coefficients. Three experimental configurations, two of which are representative of the industrial welds assessment case, are studied in view of validating the model through comparison with the simulation results. We shall thus provide a quantitative proof that taking into account the attenuation in the ATHENA code dramatically improves the results in terms of the amplitude of the echoes. The association of the code and detailed characterization of a weld's structure constitutes a remarkable breakthrough in the interpretation of the ultrasonic testing on this type of component.

Applications of Polymer Matrix Syntactic Foams

NASA Astrophysics Data System (ADS)

Gupta, Nikhil; Zeltmann, Steven E.; Shunmugasamy, Vasanth Chakravarthy; Pinisetty, Dinesh

2013-11-01

A collection of applications of polymer matrix syntactic foams is presented in this article. Syntactic foams are lightweight porous composites that found their early applications in marine structures due to their naturally buoyant behavior and low moisture absorption. Their light weight has been beneficial in weight sensitive aerospace structures. Syntactic foams have pushed the performance boundaries for composites and have enabled the development of vehicles for traveling to the deepest parts of the ocean and to other planets. The high volume fraction of porosity in syntactic foams also enabled their applications in thermal insulation of pipelines in oil and gas industry. The possibility of tailoring the mechanical and thermal properties of syntactic foams through a combination of material selection, hollow particle volume fraction, and hollow particle wall thickness has helped in rapidly growing these applications. The low coefficient of thermal expansion and dimensional stability at high temperatures are now leading their use in electronic packaging, composite tooling, and thermoforming plug assists. Methods have been developed to tailor the mechanical and thermal properties of syntactic foams independent of each other over a wide range, which is a significant advantage over other traditional particulate and fibrous composites.

Distribution network design under demand uncertainty using genetic algorithm and Monte Carlo simulation approach: a case study in pharmaceutical industry

NASA Astrophysics Data System (ADS)

Izadi, Arman; Kimiagari, Ali mohammad

2014-01-01

Distribution network design as a strategic decision has long-term effect on tactical and operational supply chain management. In this research, the location-allocation problem is studied under demand uncertainty. The purposes of this study were to specify the optimal number and location of distribution centers and to determine the allocation of customer demands to distribution centers. The main feature of this research is solving the model with unknown demand function which is suitable with the real-world problems. To consider the uncertainty, a set of possible scenarios for customer demands is created based on the Monte Carlo simulation. The coefficient of variation of costs is mentioned as a measure of risk and the most stable structure for firm's distribution network is defined based on the concept of robust optimization. The best structure is identified using genetic algorithms and 14% reduction in total supply chain costs is the outcome. Moreover, it imposes the least cost variation created by fluctuation in customer demands (such as epidemic diseases outbreak in some areas of the country) to the logistical system. It is noteworthy that this research is done in one of the largest pharmaceutical distribution firms in Iran.

Distribution network design under demand uncertainty using genetic algorithm and Monte Carlo simulation approach: a case study in pharmaceutical industry

NASA Astrophysics Data System (ADS)

Izadi, Arman; Kimiagari, Ali Mohammad

2014-05-01

Distribution network design as a strategic decision has long-term effect on tactical and operational supply chain management. In this research, the location-allocation problem is studied under demand uncertainty. The purposes of this study were to specify the optimal number and location of distribution centers and to determine the allocation of customer demands to distribution centers. The main feature of this research is solving the model with unknown demand function which is suitable with the real-world problems. To consider the uncertainty, a set of possible scenarios for customer demands is created based on the Monte Carlo simulation. The coefficient of variation of costs is mentioned as a measure of risk and the most stable structure for firm's distribution network is defined based on the concept of robust optimization. The best structure is identified using genetic algorithms and 14 % reduction in total supply chain costs is the outcome. Moreover, it imposes the least cost variation created by fluctuation in customer demands (such as epidemic diseases outbreak in some areas of the country) to the logistical system. It is noteworthy that this research is done in one of the largest pharmaceutical distribution firms in Iran.

Thermal Strain Analysis of Optic Fiber Sensors

PubMed Central

Her, Shiuh-Chuan; Huang, Chih-Ying

2013-01-01

An optical fiber sensor surface bonded onto a host structure and subjected to a temperature change is analytically studied in this work. The analysis is developed in order to assess the thermal behavior of an optical fiber sensor designed for measuring the strain in the host structure. For a surface bonded optical fiber sensor, the measuring sensitivity is strongly dependent on the bonding characteristics which include the protective coating, adhesive layer and the bonding length. Thermal stresses can be generated due to a mismatch of thermal expansion coefficients between the optical fiber and host structure. The optical fiber thermal strain induced by the host structure is transferred via the adhesive layer and protective coating. In this investigation, an analytical expression of the thermal strain and stress in the optical fiber is presented. The theoretical predictions are validated using the finite element method. Numerical results show that the thermal strain and stress are linearly dependent on the difference in thermal expansion coefficients between the optical fiber and host structure and independent of the thermal expansion coefficients of the adhesive and coating. PMID:23385407

Information-theoretic indices usage for the prediction and calculation of octanol-water partition coefficient.

PubMed

Persona, Marek; Kutarov, Vladimir V; Kats, Boris M; Persona, Andrzej; Marczewska, Barbara

2007-01-01

The paper describes the new prediction method of octanol-water partition coefficient, which is based on molecular graph theory. The results obtained using the new method are well correlated with experimental values. These results were compared with the ones obtained by use of ten other structure correlated methods. The comparison shows that graph theory can be very useful in structure correlation research.

SCI model structure determination program (OSR) user's guide. [optimal subset regression

NASA Technical Reports Server (NTRS)

1979-01-01

The computer program, OSR (Optimal Subset Regression) which estimates models for rotorcraft body and rotor force and moment coefficients is described. The technique used is based on the subset regression algorithm. Given time histories of aerodynamic coefficients, aerodynamic variables, and control inputs, the program computes correlation between various time histories. The model structure determination is based on these correlations. Inputs and outputs of the program are given.

Integration Of Heat Transfer Coefficient In Glass Forming Modeling With Special Interface Element

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moreau, P.; Gregoire, S.; Lochegnies, D.

2007-05-17

Numerical modeling of the glass forming processes requires the accurate knowledge of the heat exchange between the glass and the forming tools. A laboratory testing is developed to determine the evolution of the heat transfer coefficient in different glass/mould contact conditions (contact pressure, temperature, lubrication...). In this paper, trials are performed to determine heat transfer coefficient evolutions in experimental conditions close to the industrial blow-and-blow process conditions. In parallel of this work, a special interface element is implemented in a commercial Finite Element code in order to deal with heat transfer between glass and mould for non-meshing meshes and evolutivemore » contact. This special interface element, implemented by using user subroutines, permits to introduce the previous heat transfer coefficient evolutions in the numerical modelings at the glass/mould interface in function of the local temperatures, contact pressures, contact time and kind of lubrication. The blow-and-blow forming simulation of a perfume bottle is finally performed to assess the special interface element performance.« less

Reliability of a structured interview for admission to an emergency medicine residency program.

PubMed

Blouin, Danielle

2010-10-01

Interviews are most important in resident selection. Structured interviews are more reliable than unstructured ones. We sought to measure the interrater reliability of a newly designed structured interview during the selection process to an Emergency Medicine residency program. The critical incident technique was used to extract the desired dimensions of performance. The interview tool consisted of 7 clinical scenarios and 1 global rating. Three trained interviewers marked each candidate on all scenarios without discussing candidates' responses. Interitem consistency and estimates of variance were computed. Twenty-eight candidates were interviewed. The generalizability coefficient was 0.67. Removing the central tendency ratings increased the coefficient to 0.74. Coefficients of interitem consistency ranged from 0.64 to 0.74. The structured interview tool provided good although suboptimal interrater reliability. Increasing the number of scenarios improves reliability as does applying differential weights to the rating scale anchors. The latter would also facilitate the identification of those candidates with extreme ratings.

Aviation competition : challenges in enhancing competition in dominated markets

DOT National Transportation Integrated Search

2001-03-13

The potential shifts in aviation industry structure that would result from proposed mergers represent a crossroads for the structure of the airline industry and the state of competition and industry performance. These proposals have raised public pol...

Education, Skills and Industrial Development in the Structural Transformation of Africa. Innocenti Occasional Papers Number 3. Special Subseries: Structural Adjustment in Sub-Saharan Africa.

ERIC Educational Resources Information Center

Lall, Sanjaya

Industrial expansion remains essential for the development and structural transformation of most sub-Saharan African economies. The advantages of industrialization go beyond the provision of manufactured goods and the diversification of exports to the modernization of society. Growth rates in formal manufacturing tell little about the economic…

Remote sensing techniques for prediction of watershed runoff

NASA Technical Reports Server (NTRS)

Blanchard, B. J.

1975-01-01

Hydrologic parameters of watersheds for use in mathematical models and as design criteria for flood detention structures are sometimes difficult to quantify using conventional measuring systems. The advent of remote sensing devices developed in the past decade offers the possibility that watershed characteristics such as vegetative cover, soils, soil moisture, etc., may be quantified rapidly and economically. Experiments with visible and near infrared data from the LANDSAT-1 multispectral scanner indicate a simple technique for calibration of runoff equation coefficients is feasible. The technique was tested on 10 watersheds in the Chickasha area and test results show more accurate runoff coefficients were obtained than with conventional methods. The technique worked equally as well using a dry fall scene. The runoff equation coefficients were then predicted for 22 subwatersheds with flood detention structures. Predicted values were again more accurate than coefficients produced by conventional methods.

The explicit computation of integration algorithms and first integrals for ordinary differential equations with polynomials coefficients using trees

NASA Technical Reports Server (NTRS)

Crouch, P. E.; Grossman, Robert

1992-01-01

This note is concerned with the explicit symbolic computation of expressions involving differential operators and their actions on functions. The derivation of specialized numerical algorithms, the explicit symbolic computation of integrals of motion, and the explicit computation of normal forms for nonlinear systems all require such computations. More precisely, if R = k(x(sub 1),...,x(sub N)), where k = R or C, F denotes a differential operator with coefficients from R, and g member of R, we describe data structures and algorithms for efficiently computing g. The basic idea is to impose a multiplicative structure on the vector space with basis the set of finite rooted trees and whose nodes are labeled with the coefficients of the differential operators. Cancellations of two trees with r + 1 nodes translates into cancellation of O(N(exp r)) expressions involving the coefficient functions and their derivatives.

Electric Motor Thermal Management R&D. Annual Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bennion, Kevin

With the push to reduce component volumes, lower costs, and reduce weight without sacrificing performance or reliability, the challenges associated with thermal management increase for power electronics and electric motors. Thermal management for electric motors will become more important as the automotive industry continues the transition to more electrically dominant vehicle propulsion systems. The transition to more electrically dominant propulsion systems leads to higher-power duty cycles for electric drive systems. Thermal constraints place significant limitations on how electric motors ultimately perform, and as thermal management improves, there will be a direct trade-off between motor performance, efficiency, cost, and the sizingmore » of electric motors to operate within the thermal constraints. The goal of this research project is to support broad industry demand for data, analysis methods, and experimental techniques to improve and better understand motor thermal management. Work in FY15 focused on two areas related to motor thermal management: passive thermal performance and active convective cooling. Passive thermal performance emphasized the thermal impact of materials and thermal interfaces among materials within an assembled motor. The research tasks supported the publication of test methods and data for thermal contact resistances and direction-dependent thermal conductivity within an electric motor. Active convective cooling focused on measuring convective heat-transfer coefficients using automatic transmission fluid (ATF). Data for average convective heat transfer coefficients for direct impingement of ATF jets was published. Also, experimental hardware for mapping local-scale and stator-scale convective heat transfer coefficients for ATF jet impingement were developed.« less

Genotypic character relationship and phenotypic path coefficient analysis in chili pepper genotypes grown under tropical condition.

PubMed

Usman, Magaji G; Rafii, Mohd Y; Martini, Mohammad Y; Oladosu, Yusuff; Kashiani, Pedram

2017-03-01

Studies on genotypic and phenotypic correlations among characters of crop plants are useful in planning, evaluating and setting selection criteria for the desired characters in a breeding program. The present study aimed to estimate the phenotypic correlation coefficients among yield and yield attributed characters and to work out the direct and indirect effects of yield-related characters on yield per plant using path coefficient analysis. Twenty-six genotypes of chili pepper were laid out in a randomized complete block design with three replications. Yield per plant showed positive and highly significant (P ≤ 0.01) correlations with most of the characters studied at both the phenotypic and genotypic levels. By contrast, disease incidence and days to flowering showed a significant negative association with yield. Fruit weight and number of fruits exerted positive direct effect on yield and also had a positive and significant (P ≤ 0.01) correlation with yield per plant. However, fruit length showed a low negative direct effect with a strong and positive indirect effect through fruit weight on yield and had a positive and significant association with yield. Longer fruits, heavy fruits and a high number of fruits are variables that are related to higher yields of chili pepper under tropical conditions and hence could be used as a reliable indicator in indirect selection for yield. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

The Importance of Isomorphism for Conclusions about Homology: A Bayesian Multilevel Structural Equation Modeling Approach with Ordinal Indicators.

PubMed

Guenole, Nigel

2016-01-01

We describe a Monte Carlo study examining the impact of assuming item isomorphism (i.e., equivalent construct meaning across levels of analysis) on conclusions about homology (i.e., equivalent structural relations across levels of analysis) under varying degrees of non-isomorphism in the context of ordinal indicator multilevel structural equation models (MSEMs). We focus on the condition where one or more loadings are higher on the between level than on the within level to show that while much past research on homology has ignored the issue of psychometric isomorphism, psychometric isomorphism is in fact critical to valid conclusions about homology. More specifically, when a measurement model with non-isomorphic items occupies an exogenous position in a multilevel structural model and the non-isomorphism of these items is not modeled, the within level exogenous latent variance is under-estimated leading to over-estimation of the within level structural coefficient, while the between level exogenous latent variance is overestimated leading to underestimation of the between structural coefficient. When a measurement model with non-isomorphic items occupies an endogenous position in a multilevel structural model and the non-isomorphism of these items is not modeled, the endogenous within level latent variance is under-estimated leading to under-estimation of the within level structural coefficient while the endogenous between level latent variance is over-estimated leading to over-estimation of the between level structural coefficient. The innovative aspect of this article is demonstrating that even minor violations of psychometric isomorphism render claims of homology untenable. We also show that posterior predictive p-values for ordinal indicator Bayesian MSEMs are insensitive to violations of isomorphism even when they lead to severely biased within and between level structural parameters. We highlight conditions where poor estimation of even correctly specified models rules out empirical examination of isomorphism and homology without taking precautions, for instance, larger Level-2 sample sizes, or using informative priors.

The Importance of Isomorphism for Conclusions about Homology: A Bayesian Multilevel Structural Equation Modeling Approach with Ordinal Indicators

PubMed Central

Guenole, Nigel

2016-01-01

We describe a Monte Carlo study examining the impact of assuming item isomorphism (i.e., equivalent construct meaning across levels of analysis) on conclusions about homology (i.e., equivalent structural relations across levels of analysis) under varying degrees of non-isomorphism in the context of ordinal indicator multilevel structural equation models (MSEMs). We focus on the condition where one or more loadings are higher on the between level than on the within level to show that while much past research on homology has ignored the issue of psychometric isomorphism, psychometric isomorphism is in fact critical to valid conclusions about homology. More specifically, when a measurement model with non-isomorphic items occupies an exogenous position in a multilevel structural model and the non-isomorphism of these items is not modeled, the within level exogenous latent variance is under-estimated leading to over-estimation of the within level structural coefficient, while the between level exogenous latent variance is overestimated leading to underestimation of the between structural coefficient. When a measurement model with non-isomorphic items occupies an endogenous position in a multilevel structural model and the non-isomorphism of these items is not modeled, the endogenous within level latent variance is under-estimated leading to under-estimation of the within level structural coefficient while the endogenous between level latent variance is over-estimated leading to over-estimation of the between level structural coefficient. The innovative aspect of this article is demonstrating that even minor violations of psychometric isomorphism render claims of homology untenable. We also show that posterior predictive p-values for ordinal indicator Bayesian MSEMs are insensitive to violations of isomorphism even when they lead to severely biased within and between level structural parameters. We highlight conditions where poor estimation of even correctly specified models rules out empirical examination of isomorphism and homology without taking precautions, for instance, larger Level-2 sample sizes, or using informative priors. PMID:26973580

The determination of solubility and diffusion coefficient for solids in liquids by an inverse measurement technique using cylinders of amorphous glucose as a model compound

NASA Astrophysics Data System (ADS)

Hu, Chengyao; Huang, Pei

2011-05-01

The importance of sugar and sugar-containing materials is well recognized nowadays, owing to their application in industrial processes, particularly in the food, pharmaceutical and cosmetic industries. Because of the large numbers of those compounds involved and the relatively small number of solubility and/or diffusion coefficient data for each compound available, it is highly desirable to measure the solubility and/or diffusion coefficient as efficiently as possible and to be able to improve the accuracy of the methods used. In this work, a new technique was developed for the measurement of the diffusion coefficient of a stationary solid solute in a stagnant solvent which simultaneously measures solubility based on an inverse measurement problem algorithm with the real-time dissolved amount profile as a function of time. This study differs from established techniques in both the experimental method and the data analysis. The experimental method was developed in which the dissolved amount of solid solute in quiescent solvent was investigated using a continuous weighing technique. In the data analysis, the hybrid genetic algorithm is used to minimize an objective function containing a calculated and a measured dissolved amount with time. This is measured on a cylindrical sample of amorphous glucose in methanol or ethanol. The calculated dissolved amount, that is a function of the unknown physical properties of the solid solute in the solvent, is calculated by the solution of the two-dimensional nonlinear inverse natural convection problem. The estimated values of the solubility of amorphous glucose in methanol and ethanol at 293 K were respectively 32.1 g/100 g methanol and 1.48 g/100 g ethanol, in agreement with the literature values, and support the validity of the simultaneously measured diffusion coefficient. These results show the efficiency and the stability of the developed technique to simultaneously estimate the solubility and diffusion coefficient. Also the influence of the solution density change and the initial concentration conditions on the dissolved amount was investigated by the numerical results using the estimated parameters. It is found that the theoretical assumption to simplify the inverse measurement problem algorithm is reasonable for low solubility.

The Effect of Acidity Coefficient on Crystallization Behavior of Blast Furnace Slag Fibers

NASA Astrophysics Data System (ADS)

Tian, Tie-Lei; Zhang, Yu-Zhu; Xing, Hong-wei; Li, Jie; Zhang, Zun-Qian

2018-01-01

The chemical structure of mineral wool fiber was investigated by using Fourier Transform Infrared Spectroscopy (FTIR). Next, the glass transition temperature and the crystallization temperature of the fibers were studied. Finally, the crystallization kinetics of fiber was studied. The results show that the chemical bond structure of fibers gets more random with the increase of acidity coefficient. The crystallization phases of the fibers are mainly melilites, and also a few anorthites and diopsides. The growth mechanism of the crystals is three dimensional. The fibers with acidity coefficient of 1.2 exhibit the best thermal stability and is hard to crystallize as it has the maximum aviation energy of crystallization kinetics.

Aerodynamic Simulation Analysis of Unmanned Airborne Electronic Bomb

NASA Astrophysics Data System (ADS)

Yang, Jiaoying; Guo, Yachao

2017-10-01

For microelectronic bombs for UAVs, on the basis of the use of rotors to lift the insurance on the basis of ammunition, increased tail to increase stability. The aerodynamic simulation of the outer structure of the ammunition was carried out by FLUENT software. The resistance coefficient, the lift coefficient and the pitch moment coefficient under different angle of attack and Mach number were obtained, and the aerodynamic characteristics of the electronic bomb were studied. The pressure line diagram and the velocity line diagram of the flow around the bomb are further analyzed, and the rationality of the external structure is verified, which provides a reference for the subsequent design of the electronic bomb.

Statistical modelling of formaldehyde occupational exposure levels in French industries, 1986-2003.

PubMed

Lavoué, Jérôme; Vincent, Raymond; Gérin, Michel

2006-04-01

Occupational exposure databanks (OEDBs) have been cited as sources of exposure data for exposure surveillance and exposure assessment in epidemiology. In 2003, an extract was made from COLCHIC, the French national OEDB, of all concentrations of formaldehyde. The data were analysed with extended linear mixed-effects models in order to identify influent variables and elaborate a multi-sector picture of formaldehyde exposures. Respectively, 1401 and 1448 personal and area concentrations were available for the analysis. The fixed effects of the personal and area models explained, respectively, 57 and 53% of the total variance. Personal concentrations were related to the sampling duration (short-term higher than TWA levels), decreased with the year of sampling (-9% per year) and were higher when local exhaust ventilation was present. Personal levels taken during planned visits and for occupational illness notification purpose were consistently lower than those taken during ventilation modification programmes or because the hygienist suspected the presence of significant risk or exposure. Area concentrations were related to the sampling duration (short-term higher than TWA levels), and decreased with the year of sampling (-7% per year) and when the measurement sampling flow increased. Significant within-facility (correlation coefficient 0.4-0.5) and within-sampling campaign correlation (correlation coefficient 0.8) was found for both area and personal data. The industry/task classification appeared to have the greatest influence on exposure variability while the sample duration and the sampling flow were significant in some cases. Estimates made from the models for year 2002 showed elevated formaldehyde exposure in the fields of anatomopathological and biological analyses, operation of gluing machinery in the wood industry, operation and monitoring of mixers in the pharmaceutical industry, and garages and warehouses in urban transit authorities.

Effect of pendent chains on the interfacial properties of thin polydimethylsiloxane (PDMS) networks.

PubMed

Landherr, Lucas J T; Cohen, Claude; Archer, Lynden A

2011-05-17

The interfacial properties of end-linked polydimethylsiloxane (PDMS) films on silicon are examined. Thin cross-linked PDMS films (∼10 μm thick) were synthesized over a self-assembled monolayer supported on a silicon wafer. By systematically varying the concentration of monofunctional PDMS in a mixture with telechelic precursor molecules, structures ranging from near-ideal elastic networks to poorly cross-linked networks composed of a preponderance of dangling/pendent chains were synthesized. Lateral force microscopy (LFM) employing bead probes was used to quantify the effect of network structure on the interfacial friction coefficient and residual force. Indentation measurements employing an AFM in force mode were used to characterize the elastic modulus and the pull-off force for the films as a function of pendent chain content. These measurements were complemented with conventional mechanical rheometry measurements on similar thick network films to determine their bulk rheological properties. All networks studied manifested interfacial friction coefficients substantially lower than that of bare silicon. PDMS networks with the lowest pendent chain content displayed friction coefficients close to 1 order of magnitude lower than that of bare silicon, whereas networks with the highest pendent chain content manifested friction coefficients about 3 times lower than that of bare silicon. At intermediate sliding velocities, a crossover in the interfacial friction coefficient was observed, wherein cross-linked PDMS films with the least amount of pendent chains exhibit the highest friction coefficient. These observations are discussed in terms of the structure of the films and relaxation dynamics of elastic strands and dangling chains in tethered network films.

Effects of molecular size and structure on self-diffusion coefficient and viscosity for saturated hydrocarbons having six carbon atoms.

PubMed

Iwahashi, Makio; Kasahara, Yasutoshi

2007-01-01

Self-diffusion coefficients and viscosities for the saturated hydrocarbons having six carbon atoms such as hexane, 2-methylpentane (2MP), 3-methylpentane (3MP), 2,2-dimethylbutane (22DMB), 2,3-dimethylbutane (23DMB), methylcyclopentane (McP) and cyclohexane (cH) were measured at various constant temperatures; obtained results were discussed in connection with their molar volumes, molecular structures and thermodynamic properties. The values of self-diffusion coefficients as the microscopic property were inversely proportional to those of viscosities as the macroscopic property. The order of their viscosities was almost same to those of their melting temperatures and enthalpies of fusion, which reflect the attractive interactions among their molecules. On the other hand, the order of the self-diffusion coefficients inversely related to the order of the melting temperatures and the enthalpies of the fusion. Namely, the compound having the larger attractive interaction mostly shows the less mobility in its liquid state, e.g., cyclohexane (cH), having the largest attractive interaction and the smallest molar volume exhibits an extremely large viscosity and small self-diffusion coefficient comparing with other hydrocarbons. However, a significant exception was 22DMB, being most close to a sphere: In spite of the smallest attractive interaction and the largest molar volume of 22DMB in the all samples, it has the thirdly larger viscosity and the thirdly smaller self-diffusion coefficient. Consequently, the dynamical properties such as self-diffusion and viscosity for the saturated hydrocarbons are determined not only by their attractive interactions but also by their molecular structures.

A thermo-elastoplastic model for soft rocks considering structure

NASA Astrophysics Data System (ADS)

He, Zuoyue; Zhang, Sheng; Teng, Jidong; Xiong, Yonglin

2017-11-01

In the fields of nuclear waste geological deposit, geothermy and deep mining, the effects of temperature on the mechanical behaviors of soft rocks cannot be neglected. Experimental data in the literature also showed that the structure of soft rocks cannot be ignored. Based on the superloading yield surface and the concept of temperature-deduced equivalent stress, a thermo-elastoplastic model for soft rocks is proposed considering the structure. Compared to the superloading yield surface, only one parameter is added, i.e. the linear thermal expansion coefficient. The predicted results and the comparisons with experimental data in the literature show that the proposed model is capable of simultaneously describing heat increase and heat decrease of soft rocks. A stronger initial structure leads to a greater strength of the soft rocks. Heat increase and heat decrease can be converted between each other due to the change of the initial structure of soft rocks. Furthermore, regardless of the heat increase or heat decrease, a larger linear thermal expansion coefficient or a greater temperature always leads to a much rapider degradation of the structure. The degradation trend will be more obvious for the coupled greater values of linear thermal expansion coefficient and temperature. Lastly, compared to heat decrease, the structure will degrade more easily in the case of heat increase.

Three-gene identity coefficients demonstrate that clonal reproduction promotes inbreeding and spatial relatedness in yellow-cedar, Callitropsis nootkatensis.

PubMed

Thompson, Stacey Lee; Bérubé, Yanik; Bruneau, Anne; Ritland, Kermit

2008-10-01

Asexual reproduction has the potential to promote population structuring through matings between clones as well as through limited dispersal of related progeny. Here we present an application of three-gene identity coefficients that tests whether clonal reproduction promotes inbreeding and spatial relatedness within populations. With this method, the first two genes are sampled to estimate pairwise relatedness or inbreeding, whereas the third gene is sampled from either a clone or a sexually derived individual. If three-gene coefficients are significantly greater for clones than nonclones, then clonality contributes excessively to genetic structure. First, we describe an estimator of three-gene identity and briefly evaluate its properties. We then use this estimator to test the effect of clonality on the genetic structure within populations of yellow-cedar (Callitropsis nootkatensis) using a molecular marker survey. Five microsatellite loci were genotyped for 485 trees sampled from nine populations. Our three-gene analyses show that clonal ramets promote inbreeding and spatial structure in most populations. Among-population correlations between clonal extent and genetic structure generally support these trends, yet with less statistical significance. Clones appear to contribute to genetic structure through the limited dispersal of offspring from replicated ramets of the same clonal genet, whereas this structure is likely maintained by mating among these relatives.

Effect of the porous structure of activated carbon on the adsorption kinetics of gold(I) cyanide complex

NASA Astrophysics Data System (ADS)

Ibragimova, P. I.; Grebennikov, S. F.; Gur'yanov, V. V.; Fedyukevich, V. A.; Vorob'ev-Desyatovskii, N. V.

2014-06-01

The effect the porous structure of activated carbons obtained from furfural and coconut shells has on the kinetics of [Au(CN)2]- ion adsorption is studied. Effective diffusion coefficients for [Au(CN)2]- anions in transport and adsorbing pores and mass transfer coefficients in a transport system of the pores and in microporous zones are calculated using the statistical moments of the kinetic curve.

Temperature-dependent solubility transition of Na₂SO₄ in water and the effect of NaCl therein: solution structures and salt water dynamics.

PubMed

Bharmoria, Pankaj; Gehlot, Praveen Singh; Gupta, Hariom; Kumar, Arvind

2014-11-06

Dual, aqueous solubility behavior of Na2SO4 as a function of temperatures is still a natural enigma lying unresolved in the literature. The solubility of Na2SO4 increases up to 32.38 °C and decreases slightly thereafter at higher temperatures. We have thrown light on this phenomenon by analyzing the Na2SO4-water clusters (growth and stability) detected from temperature-dependent dynamic light scattering experiments, solution compressibility changes derived from the density and speed of sound measurements, and water structural changes/Na2SO4 (ion pair)-water interactions observed from the FT-IR and 2D DOSY (1)H NMR spectroscopic investigations. It has been observed that Na2SO4-water clusters grow with an increase in Na2SO4 concentration (until the solubility transition temperature) and then start decreasing afterward. An unusual decrease in cluster size and solution compressibility has been observed with the rise in temperature for the Na2SO4 saturated solutions below the solubility transition temperature, whereas an inverse pattern is followed thereafter. DOSY experiments have indicated different types of water cluster species in saturated solutions at different temperatures with varying self-diffusion coefficients. The effect of NaCl (5-15 wt %) on the solubility behavior of Na2SO4 at different temperatures has also been examined. The studies are important from both fundamental and industrial application points of view, for example, toward the clean separation of NaCl and Na2SO4 from the effluent streams of textile and tannery industries.

Support vector machine regression (SVR/LS-SVM)--an alternative to neural networks (ANN) for analytical chemistry? Comparison of nonlinear methods on near infrared (NIR) spectroscopy data.

PubMed

Balabin, Roman M; Lomakina, Ekaterina I

2011-04-21

In this study, we make a general comparison of the accuracy and robustness of five multivariate calibration models: partial least squares (PLS) regression or projection to latent structures, polynomial partial least squares (Poly-PLS) regression, artificial neural networks (ANNs), and two novel techniques based on support vector machines (SVMs) for multivariate data analysis: support vector regression (SVR) and least-squares support vector machines (LS-SVMs). The comparison is based on fourteen (14) different datasets: seven sets of gasoline data (density, benzene content, and fractional composition/boiling points), two sets of ethanol gasoline fuel data (density and ethanol content), one set of diesel fuel data (total sulfur content), three sets of petroleum (crude oil) macromolecules data (weight percentages of asphaltenes, resins, and paraffins), and one set of petroleum resins data (resins content). Vibrational (near-infrared, NIR) spectroscopic data are used to predict the properties and quality coefficients of gasoline, biofuel/biodiesel, diesel fuel, and other samples of interest. The four systems presented here range greatly in composition, properties, strength of intermolecular interactions (e.g., van der Waals forces, H-bonds), colloid structure, and phase behavior. Due to the high diversity of chemical systems studied, general conclusions about SVM regression methods can be made. We try to answer the following question: to what extent can SVM-based techniques replace ANN-based approaches in real-world (industrial/scientific) applications? The results show that both SVR and LS-SVM methods are comparable to ANNs in accuracy. Due to the much higher robustness of the former, the SVM-based approaches are recommended for practical (industrial) application. This has been shown to be especially true for complicated, highly nonlinear objects.

Design, fabrication and test of graphite/epoxy metering truss structure components, phase 3

NASA Technical Reports Server (NTRS)

1974-01-01

The design, materials, tooling, manufacturing processes, quality control, test procedures, and results associated with the fabrication and test of graphite/epoxy metering truss structure components exhibiting a near zero coefficient of thermal expansion are described. Analytical methods were utilized, with the aid of a computer program, to define the most efficient laminate configurations in terms of thermal behavior and structural requirements. This was followed by an extensive material characterization and selection program, conducted for several graphite/graphite/hybrid laminate systems to obtain experimental data in support of the analytical predictions. Mechanical property tests as well as the coefficient of thermal expansion tests were run on each laminate under study, the results of which were used as the selection criteria for the single most promising laminate. Further coefficient of thermal expansion measurement was successfully performed on three subcomponent tubes utilizing the selected laminate.

Optical properties of the Tietz-Hua quantum well under the applied external fields

NASA Astrophysics Data System (ADS)

Kasapoglu, E.; Sakiroglu, S.; Ungan, F.; Yesilgul, U.; Duque, C. A.; Sökmen, I.

2017-12-01

In this study, the effects of the electric and magnetic fields as well as structure parameter- γ on the total absorption coefficient, including linear and third order nonlinear absorption coefficients for the optical transitions between any two subband in the Tietz-Hua quantum well have been investigated. The optical transitions were investigated by using the density matrix formalism and the perturbation expansion method. The Tietz-Hua quantum well becomes narrower (wider) when the γ - structure parameter increases (decreases) and so the energies of the bound states will be functions of this parameter. Therefore, we can provide the red or blue shift in the peak position of the absorption coefficient by changing the strength of the electric and magnetic fields as well as the structure parameters and these results can be used to adjust and control the optical properties of the Tietz-Hua quantum well.

Structure, thermal expansion coefficient and phase stability of La2(Zr0.7Ce0.3)2O7 studied by molecular dynamic simulation and experiment

NASA Astrophysics Data System (ADS)

Che, JunWei; Liu, XiangYang; Wang, XueZhi; Liang, GongYing

2018-04-01

This paper presents structure, thermal expansion coefficient and phase stability of La2(Zr0.7Ce0.3)2O7 (LZ7C3) ceramic by both theoretical and experimental results. It was found out that LZ7C3 powders had a pyrochlore structure after being heat-treated at temperatures higher than 1473 K or higher according to XRD and TEM results. The calculated average thermal expansion coefficient (TEC) was 7.12 × 10-6 K-1, which is a little smaller than experiment result, but changes of calculated average TECs of LZ, YSZ and LZ7C3 had the same trend with experimental results. Finally, the radial distribution function (RDF) was calculated to study the phase stability of LZ7C3.

Phase-resolved reflectance spectroscopy on layered turbid media

NASA Astrophysics Data System (ADS)

Hielscher, Andreas H.; Liu, Hanli; Chance, Britton; Tittel, Frank K.; Jacques, Steven L.

1995-05-01

In this study, we investigate the influence of layered tissue structures on the phase-resolved reflectance. As a particular example, we consider the affect of the skin, skull, and meninges on noninvasive blood oxygenation determination of the brain. In this case, it's important to know how accurate one can measure the absorption coefficient of the brain through the enclosing layers of different tissues. Experiments were performed on layered gelatin tissue phantoms and the results compared to diffusion theory. It is shown that when a high absorbing medium is placed on top of a low absorbing medium, the absorption coefficient of the lower layer is accessible. In the inverse case, where a low absorbing medium is placed on top of a high absorbing medium, the absorption coefficient of the underlying medium can only be determined if the differences in the absorption coefficient are small, or the top layer is very thin. Investigations on almost absorption and scattering free layers, like the cerebral fluid filled arachnoid, reveal that the determination of the absorption coefficient is barely affected by these kinds of structures.

Non-Price Competition and the Structure of the Online Information Industry: Q-Analysis of Medical Databases and Hosts.

ERIC Educational Resources Information Center

Davies, Roy

1987-01-01

Discussion of the online information industry emphasizes the effects of non-price competition on its structure and the firms involved. Q-analysis is applied to data on medical databases and hosts, changes over a three-year period are identified, and an optimum structure for the industry based on economic theory is considered. (Author/LRW)

Structural change in industry and futures for the electricity industry. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schwartz, P.; Harris, G.

1995-06-01

The electricity supply industry in the United States has been experiencing major technological changes and economics of the business have altered dramatically since the passage of the Public Utilities Regulatory Policies Act of 1978 (PURPA). This opening of power generation business to competition was under-pinned by significant increases in gas turbine efficiency, commercialization of smaller units with high efficiencies, low gas prices, and cost consciousness on the part of independent power producers (IPPs) and major industrial customers. The pace of change continues to accelerate, driven by ongoing technological innovations and customer demands for better, more customized services and lower costs.more » The purpose of this report is to provoke further thought on the likely course of structural change in the electric utility industry over the next twenty years. The prime focus of the report is on technological change and its impact on economics, and the resulting organizational and structural change. This report begins with a brief look at structural change in several capital-intensive industries to identify common patterns applicable to the electricity industry. The industries selected have network-like operations, similar to the electric utility industry. This is followed by two scenarios which illuminate different plausible futures for the electric power industry. The report concludes with insights on the potential course of regulations and suitable strategies to prosper during the transition phase.« less

SAW propagation characteristics of TeO3/3C-SiC/LiNbO3 layered structure

NASA Astrophysics Data System (ADS)

Soni, Namrata D.

2018-04-01

Surface acoustic wave (SAW) devices based on Lithium Niobate (LiNbO3) single crystal are advantageous because of its high SAW phase velocity, electromechanical coupling coefficient and cost effectiveness. In the present work a new multi-layered TeO3/3C-SiC/128° Y-X LiNbO3 SAW device has been proposed. SAW propagation properties such as phase velocity, coupling coefficient and temperature coefficient of delay (TCD) of the TeO3/SiC/128° Y-X LiNbO3 multi layered structure is examined using theoretical calculations. It is found that the integration of 0.09λ thick 3C-SiC over layer on 128° Y-X LiNbO3 increases its electromechanical coupling coefficient from 5.3% to 9.77% and SAW velocity from 3800 ms‑1 to 4394 ms‑1. The SiC/128° Y-X LiNbO3 bilayer SAW structure exhibits a high positive TCD value. A temperature stable layered SAW device could be obtained with introduction of 0.007λ TeO3 over layer on SiC/128° Y-X LiNbO3 bilayer structure without sacrificing the efficiency of the device. The proposed TeO3/3C-SiC/128° Y-X LiNbO3 multi-layered SAW structure is found to be cost effective, efficient, temperature stable and suitable for high frequency application in harsh environment.

Dependence of toxicity of silver nanoparticles on Pseudomonas putida biofilm structure.

PubMed

Thuptimdang, Pumis; Limpiyakorn, Tawan; Khan, Eakalak

2017-12-01

Susceptibility of biofilms with different physical structures to silver nanoparticles (AgNPs) was studied. Biofilms of Pseudomonas putida KT2440 were formed in batch conditions under different carbon sources (glucose, glutamic acid, and citrate), glucose concentrations (5 and 50 mM), and incubation temperatures (25 and 30 °C). The biofilms were observed using confocal laser scanning microscopy for their physical characteristics (biomass amount, thickness, biomass volume, surface to volume ratio, and roughness coefficient). The biofilms forming under different growth conditions exhibited different physical structures. The biofilm thickness and the roughness coefficient were found negatively and positively correlated with the biofilm susceptibility to AgNPs, respectively. The effect of AgNPs on biofilms was low (1-log reduction of cell number) when the biofilms had high biomass amount, high thickness, high biomass volume, low surface to volume ratio, and low roughness coefficient. Furthermore, the extracellular polymeric substance (EPS) stripping process was applied to confirm the dependence of susceptibility to AgNPs on the structure of biofilm. After the EPS stripping process, the biofilms forming under different conditions showed reduction in thickness and biomass volume, and increases in surface to volume ratio and roughness coefficient, which led to more biofilm susceptibility to AgNPs. The results of this study suggest that controlling the growth conditions to alter the biofilm physical structure is a possible approach to reduce the impact of AgNPs on biofilms in engineered and natural systems. Copyright © 2017 Elsevier Ltd. All rights reserved.

Revealing mesoscopic structural universality with diffusion.

PubMed

Novikov, Dmitry S; Jensen, Jens H; Helpern, Joseph A; Fieremans, Els

2014-04-08

Measuring molecular diffusion is widely used for characterizing materials and living organisms noninvasively. This characterization relies on relations between macroscopic diffusion metrics and structure at the mesoscopic scale commensurate with the diffusion length. Establishing such relations remains a fundamental challenge, hindering progress in materials science, porous media, and biomedical imaging. Here we show that the dynamical exponent in the time dependence of the diffusion coefficient distinguishes between the universality classes of the mesoscopic structural complexity. Our approach enables the interpretation of diffusion measurements by objectively selecting and modeling the most relevant structural features. As an example, the specific values of the dynamical exponent allow us to identify the relevant mesoscopic structure affecting MRI-measured water diffusion in muscles and in brain, and to elucidate the structural changes behind the decrease of diffusion coefficient in ischemic stroke.

On quantification of residual ink content and deinking efficiency in recycling of mixed office waste paper

Treesearch

Bo Li; Gaosheng Wang; Kefu Chen; David W. Vahey; Junyong Zhu

2011-01-01

Although (flotation) deinking has been a common industry practice for several decades, true residual ink content and deinking efficiency have never been quantified. Paper brightness and ERIC (Effective Residual Ink Concentration), based on measurements of the absorption coefficient of deinked pulp, have been used to determine performance of flotation deinking processes...

What Supports an Aeroplane? Force, Momentum, Energy and Power in Flight

ERIC Educational Resources Information Center

Robertson, David

2014-01-01

Some apparently confusing aspects of Newton's laws as applied to an aircraft in normal horizontal flight are neatly resolved by a careful analysis of force, momentum, energy and power. A number of related phenomena are explained at the same time, including the lift and induced drag coefficients, used empirically in the aviation industry.

Shear Viscosity Coefficient of 5d Liquid Transition Metals

NASA Astrophysics Data System (ADS)

Thakor, P. B.; Sonvane, Y. A.; Gajjar, P. N.; Jani, A. R.

2011-07-01

In the present paper we have calculated shear viscosity coefficient (η) of 5 d liquid transition metals. To calculate effective pair potential ν(r) and pair distribution function g(r) we have used our own newly constructed model potential and Percus- Yevick hard sphere (PYHS) structure factor S(q) respectively. We have also investigated the effect of different correction function like Hartree (H), Taylor (T) and Sarkar et al. (S) on shear viscosity coefficient (η). Our newly constructed model potential successfully explains the shear viscosity coefficient (η) of 5 d liquid transition metals.

Study on Web-Based Tool for Regional Agriculture Industry Structure Optimization Using Ajax

NASA Astrophysics Data System (ADS)

Huang, Xiaodong; Zhu, Yeping

According to the research status of regional agriculture industry structure adjustment information system and the current development of information technology, this paper takes web-based regional agriculture industry structure optimization tool as research target. This paper introduces Ajax technology and related application frameworks to build an auxiliary toolkit of decision support system for agricultural policy maker and economy researcher. The toolkit includes a “one page” style component of regional agriculture industry structure optimization which provides agile arguments setting method that enables applying sensitivity analysis and usage of data and comparative advantage analysis result, and a component that can solve the linear programming model and its dual problem by simplex method.

Influence of chloride in mortar made of Portland cement types II, III, and V on the near-field microwave reflection properties

NASA Astrophysics Data System (ADS)

Hu, Cairong; Benally, Aaron D.; Case, Tobias; Zoughi, Reza; Kurtis, Kimberly

2000-07-01

Corrosion of steel rebar in reinforced concrete structures, can be induced by the presence of chloride in the structure. Corrosion of steel rebar is a problematic issue in the construction industry as it compromises the strength and integrity of the structure. Although techniques exist for chloride detection and its migration into a structure, they are destructive, time consuming and cannot be used for the interrogation of large surfaces. In this investigation three different portland cement types; namely, ASTM types II, III and V were used, and six cubic (8' X 8' X 8') mortar specimens were produced all with water-to-cement (w/c) ratio of 0.6 and sand-to-cement (s/c) ratio of 1.5. Tap water was used when producing three of these specimens (one of each cement type). For the other three specimens calcium chloride was added to the mixing tap water resulting in a salinity of 2.5%. These specimens were placed in a hydration room for one day and thereafter left it the room temperature with low humidity. The reflection properties of these specimens, using an open-ended rectangular waveguide probe, were monitored daily at 3 GHz (S-band) and 10 GHz (X-band). The results show the influence of cement type on the reflection coefficient as well as the influence of chloride on the curing process and setting time.

Implications of NGA for NEHRP site coefficients

USGS Publications Warehouse

Borcherdt, Roger D.

2012-01-01

Three proposals are provided to update tables 11.4-1 and 11.4-2 of Minimum Design Loads for Buildings and Other Structures (7-10), by the American Society of Civil Engineers (2010) (ASCE/SEI 7-10), with site coefficients implied directly by NGA (Next Generation Attenuation) ground motion prediction equations (GMPEs). Proposals include a recommendation to use straight-line interpolation to infer site coefficients at intermediate values of ̅vs (average shear velocity). Site coefficients are recommended to ensure consistency with ASCE/SEI 7-10 MCER (Maximum Considered Earthquake) seismic-design maps and simplified site-specific design spectra procedures requiring site classes with associated tabulated site coefficients and a reference site class with unity site coefficients. Recommended site coefficients are confirmed by independent observations of average site amplification coefficients inferred with respect to an average ground condition consistent with that used for the MCER maps. The NGA coefficients recommended for consideration are implied directly by the NGA GMPEs and do not require introduction of additional models.

Atomic Oxygen Textured Polymers

NASA Technical Reports Server (NTRS)

Banks, Bruce A.; Rutledge, Sharon K.; Hunt, Jason D.; Drobotij, Erin; Cales, Michael R.; Cantrell, Gidget

1995-01-01

Atomic oxygen can be used to microscopically alter the surface morphology of polymeric materials in space or in ground laboratory facilities. For polymeric materials whose sole oxidation products are volatile species, directed atomic oxygen reactions produce surfaces of microscopic cones. However, isotropic atomic oxygen exposure results in polymer surfaces covered with lower aspect ratio sharp-edged craters. Isotropic atomic oxygen plasma exposure of polymers typically causes a significant decrease in water contact angle as well as altered coefficient of static friction. Such surface alterations may be of benefit for industrial and biomedical applications. The results of atomic oxygen plasma exposure of thirty-three (33) different polymers are presented, including typical morphology changes, effects on water contact angle, and coefficient of static friction.

Steady State Transportation Cooling in Porous Media Under Local, Non-Thermal Equilibrium Fluid Flow

NASA Technical Reports Server (NTRS)

Rodriquez, Alvaro Che

2002-01-01

An analytical solution to the steady-state fluid temperature for 1-D (one dimensional) transpiration cooling has been derived. Transpiration cooling has potential use in the aerospace industry for protection against high heating environments for re-entry vehicles. Literature for analytical treatments of transpiration cooling has been largely confined to the assumption of thermal equilibrium between the porous matrix and fluid. In the present analysis, the fundamental fluid and matrix equations are coupled through a volumetric heat transfer coefficient and investigated in non-thermal equilibrium. The effects of varying the thermal conductivity of the solid matrix and the heat transfer coefficient are investigated. The results are also compared to existing experimental data.

A classification system for characterization of physical and non-physical work factors.

PubMed

Genaidy, A; Karwowski, W; Succop, P; Kwon, Y G; Alhemoud, A; Goyal, D

2000-01-01

A comprehensive evaluation of work-related performance factors is a prerequisite to developing integrated and long-term solutions to workplace performance improvement. This paper describes a work-factor classification system that categorizes the entire domain of workplace factors impacting performance. A questionnaire-based instrument was developed to implement this classification system in industry. Fifty jobs were evaluated in 4 different service and manufacturing companies using the proposed questionnaire-based instrument. The reliability coefficients obtained from the analyzed jobs were considered good (0.589 to 0.862). In general, the physical work factors resulted in higher reliability coefficients (0.847 to 0.862) than non-physical work factors (0.589 to 0.768).

Analysis of an industry in transition.

PubMed

Baliga, B R; Johnson, B

1986-12-01

The health care industry is undergoing major structural changes. The significance of these changes for individual competitors moving toward the 1990s is not yet clear. This article assesses the implications of the current changes by applying Porter's industry structure and generic strategy frameworks to the health care industry. Present trends are compared to this analysis to highlight areas where individual hospitals might improve their competitive positioning.

Experimental application of OMA solutions on the model of industrial structure

NASA Astrophysics Data System (ADS)

Mironov, A.; Mironovs, D.

2017-10-01

It is very important and sometimes even vital to maintain reliability of industrial structures. High quality control during production and structural health monitoring (SHM) in exploitation provides reliable functioning of large, massive and remote structures, like wind generators, pipelines, power line posts, etc. This paper introduces a complex of technological and methodical solutions for SHM and diagnostics of industrial structures, including those that are actuated by periodic forces. Solutions were verified on a wind generator scaled model with integrated system of piezo-film deformation sensors. Simultaneous and multi-patch Operational Modal Analysis (OMA) approaches were implemented as methodical means for structural diagnostics and monitoring. Specially designed data processing algorithms provide objective evaluation of structural state modification.

Consumptive Water-Use Coefficients for the Great Lakes Basin and Climatically Similar Areas

USGS Publications Warehouse

Shaffer, Kimberly H.; Runkle, Donna L.

2007-01-01

Consumptive water use is the portion of water withdrawn (for a particular use) that is evaporated, transpired, incorporated into products or crops, consumed by humans or livestock, or otherwise removed from the immediate water environment. This report, which is organized by water?use categories, includes consumptive?use coefficients for the Great Lakes Basin (including Canada) and for areas climatically similar to the Great Lakes Basin. This report also contains an annotated bibliography of consumptive water?use coefficients. Selected references are listed for consumptive?use data from elsewhere in the world. For the industrial water?use category, the median consumptive?use coefficients were 10 percent for the Great Lakes Basin, climatically similar areas, and the world; the 25th and 75th percentiles for these geographic areas were comparable within 6 percent. The combined domestic and public?supply consumptive?use statistics (median, 25th and 75th percentiles) were between 10 to 20 percent for the various geographic areas. Although summary statistics were similar for coefficients in the livestock and irrigation water?use categories for the Great Lakes Basin and climatically similar areas, statistic values for the world on a whole were substantially lower (15 to 28 percent lower). Commercial and thermoelectric power consumptive?use coefficient statistics (median, 25th, and 75th percentile) also were comparable for the Great Lakes Basin and climatically similar areas, within 2 percent. References for other countries were not found for commercial and thermoelectric power water?use categories. The summary statistics for the mining consumptive?use coefficients varied, likely because of differences in types of mining, processes, or equipment.

Neo-Industrial and Sustainable Development of Russia as Mineral Resources Exploiting Country

NASA Astrophysics Data System (ADS)

Prokudina, Marina; Zhironkina, Olga; Kalinina, Oksana; Gasanov, Magerram; Agafonov, Felix

2017-11-01

In the Russian economy, the world leadership in the extraction of different mineral resources is combined with the potential for their processing and a significant scientific sector. Innovative development of raw materials extraction is impossible without the parallel technological modernization of the high-tech sector. In general, the complex of these processes is a neo-industrialization of the economy. Neo-industrially oriented transformation of the economy reflects complex changes in its structure, the transformation of established stable relationships between various elements of the system of social production that determine macroeconomic proportions. Neo-industrial transformations come along with the modification of economic relations associated with investments, innovations, labor and income distribution, with the process of locating productive forces and regulating the economy by the government. Neo-industrialization of economy is not only significant changes in its technological and reproductive structure (the development of high-tech industries, the integration of science and industry), but, above all, the implementation of a system structural policy of innovative development of raw material industry and the recovery of manufacturing industries on a new technological basis.

[Review of lime carbon sink.

PubMed

Liu, Li Li; Ling, Jiang Hua; Tie, Li; Wang, Jiao Yue; Bing, Long Fei; Xi, Feng Ming

2018-01-01

Under the background of "missing carbon sink" mystery and carbon capture and storage (CCS) technology development, this paper summarized the lime material flow process carbon sink from the lime carbonation principles, impact factors, and lime utilization categories in chemical industry, metallurgy industry, construction industry, and lime kiln ash treatment. The results showed that the lime carbonation rate coefficients were mainly impacted by materials and ambient conditions; the lime carbon sink was mainly in chemical, metallurgy, and construction industries; and current researches focused on the mechanisms and impact factors for carbonation, but their carbon sequestration calculation methods had not been proposed. Therefore, future research should focus on following aspects: to establish a complete system of lime carbon sequestration accounting method in view of material flow; to calculate lime carbon sequestration in both China and the world and explain their offset proportion of CO 2 emission from lime industrial process; to analyze the contribution of lime carbon sequestration to missing carbon sink for clarifying part of missing carbon sinks; to promote the development of carbon capture and storage technology and provide some scientific bases for China's international negotiations on climate change.

Analysis of inter-country input-output table based on citation network: How to measure the competition and collaboration between industrial sectors on the global value chain

PubMed Central

2017-01-01

The input-output table is comprehensive and detailed in describing the national economic system with complex economic relationships, which embodies information of supply and demand among industrial sectors. This paper aims to scale the degree of competition/collaboration on the global value chain from the perspective of econophysics. Global Industrial Strongest Relevant Network models were established by extracting the strongest and most immediate industrial relevance in the global economic system with inter-country input-output tables and then transformed into Global Industrial Resource Competition Network/Global Industrial Production Collaboration Network models embodying the competitive/collaborative relationships based on bibliographic coupling/co-citation approach. Three indicators well suited for these two kinds of weighted and non-directed networks with self-loops were introduced, including unit weight for competitive/collaborative power, disparity in the weight for competitive/collaborative amplitude and weighted clustering coefficient for competitive/collaborative intensity. Finally, these models and indicators were further applied to empirically analyze the function of sectors in the latest World Input-Output Database, to reveal inter-sector competitive/collaborative status during the economic globalization. PMID:28873432

Analysis of inter-country input-output table based on citation network: How to measure the competition and collaboration between industrial sectors on the global value chain.

PubMed

Xing, Lizhi

2017-01-01

The input-output table is comprehensive and detailed in describing the national economic system with complex economic relationships, which embodies information of supply and demand among industrial sectors. This paper aims to scale the degree of competition/collaboration on the global value chain from the perspective of econophysics. Global Industrial Strongest Relevant Network models were established by extracting the strongest and most immediate industrial relevance in the global economic system with inter-country input-output tables and then transformed into Global Industrial Resource Competition Network/Global Industrial Production Collaboration Network models embodying the competitive/collaborative relationships based on bibliographic coupling/co-citation approach. Three indicators well suited for these two kinds of weighted and non-directed networks with self-loops were introduced, including unit weight for competitive/collaborative power, disparity in the weight for competitive/collaborative amplitude and weighted clustering coefficient for competitive/collaborative intensity. Finally, these models and indicators were further applied to empirically analyze the function of sectors in the latest World Input-Output Database, to reveal inter-sector competitive/collaborative status during the economic globalization.

Revitalization model of tapioca industry through environmental awareness reinforcement for minimizing water body contamination

NASA Astrophysics Data System (ADS)

Banowati, E.; Indriyanti, D. R.; Juhadi

2018-03-01

Tapioca industry in Margoyoso District is a household industry which positively contributes to the growth of the region's economy as it is able to absorb 6,61% of productive age populationor absorb 3,300 workers.On the other hand, the industry impacts contamination of river water in the form of pollutants dissolved materials and particulates into water bodies so that the quality of water decreases even does not work anymore in accordance with the allocation for irrigation or run off of agriculture. The purpose of this research is to: strengthen environmental awareness; calculate the success of the reinforcement action and minimize water body contamination. The research was conducted in two villages of tapioca industry center in Margoyoso district - Pati Regency Administration Area. The determination coefficient of R Square is 0.802 which indicates a successful effort of 80.2%. Regression equation Y = 34.097 + 0.608 X. Industrial entrepreneur's concern increased on 8.45 from total indicator or position to 70.72 so that the gradual effort showed success to minimize water contamination of Suwatu River. The business community of tapioca should build installation of wastewater treatment.

Problems in the regulatory policy of the drug market

PubMed Central

Miziara, Nathália Molleis; Coutinho, Diogo Rosenthal

2015-01-01

OBJECTIVE Analyze the implementation of drug price regulation policy by the Drug Market Regulation Chamber. METHODS This is an interview-based study, which was undertaken in 2012, using semi-structured questionnaires with social actors from the pharmaceutical market, the pharmaceuticals industry, consumers and the regulatory agency. In addition, drug prices were compiled based on surveys conducted in the state of Sao Paulo, at the point of sale, between February 2009 and May 2012. RESULTS The mean drug prices charged at the point of sale (pharmacies) were well below the maximum price to the consumer, compared with many drugs sold in Brazil. Between 2009 and 2012, 44 of the 129 prices, corresponding to 99 drugs listed in the database of compiled prices, showed a variation of more than 20.0% in the mean prices at the point of sale and the maximum price to the consumer. In addition, many laboratories have refused to apply the price adequacy coefficient in their sales to government agencies. CONCLUSIONS The regulation implemented by the pharmaceutical market regulator was unable to significantly control prices of marketed drugs, without succeeding to push them to levels lower than those determined by the pharmaceutical industry and failing, therefore, in its objective to promote pharmaceutical support for the public. It is necessary reconstruct the regulatory law to allow market prices to be reduced by the regulator as well as institutional strengthen this government body. PMID:26083945

Approximate analytical solutions in the analysis of elastic structures of complex geometry

NASA Astrophysics Data System (ADS)

Goloskokov, Dmitriy P.; Matrosov, Alexander V.

2018-05-01

A method of analytical decomposition for analysis plane structures of a complex configuration is presented. For each part of the structure in the form of a rectangle all the components of the stress-strain state are constructed by the superposition method. The method is based on two solutions derived in the form of trigonometric series with unknown coefficients using the method of initial functions. The coefficients are determined from the system of linear algebraic equations obtained while satisfying the boundary conditions and the conditions for joining the structure parts. The components of the stress-strain state of a bent plate with holes are calculated using the analytical decomposition method.

A theory of the inverse magnetoelectric effect in layered magnetostrictive-piezoelectric structures

NASA Astrophysics Data System (ADS)

Filippov, D. A.; Radchenko, G. S.; Firsova, T. O.; Galkina, T. A.

2017-05-01

A theory of the inverse magnetoelectric effect in layered structures has been presented. The theory is based on solving the equations of elastodynamics and electrostatics separately for the magnetostrictive and piezoelectric phases, taking into account the conditions at the interface between the phases. Expressions for the coefficient of inverse magnetoelectric conversion through the parameters characterizing the magnetostrictive and piezoelectric phases have been obtained. Theoretical dependences of the inverse magnetoelectric conversion coefficient on the frequency of the alternating-current electric field for the three-layer PZT-Ni-PZT structure and the two-layer terfenol- D-PZT structure have been calculated. The results of the calculations are in good agreement with the experimental data.

Thermal expansion behavior study of Co nanowire array with in situ x-ray diffraction and x-ray absorption fine structure techniques

NASA Astrophysics Data System (ADS)

Mo, Guang; Cai, Quan; Jiang, Longsheng; Wang, Wei; Zhang, Kunhao; Cheng, Weidong; Xing, Xueqing; Chen, Zhongjun; Wu, Zhonghua

2008-10-01

In situ x-ray diffraction and x-ray absorption fine structure techniques were used to study the structural change of ordered Co nanowire array with temperature. The results show that the Co nanowires are polycrystalline with hexagonal close packed structure without phase change up until 700 °C. A nonlinear thermal expansion behavior has been found and can be well described by a quadratic equation with the first-order thermal expansion coefficient of 4.3×10-6/°C and the second-order thermal expansion coefficient of 5.9×10-9/°C. The mechanism of this nonlinear thermal expansion behavior is discussed.

Thin film separators with ion transport properties for energy applications

NASA Astrophysics Data System (ADS)

Li, Zhongyuan

2017-09-01

Recent years, along with the increasing need of energy, energy storage also becomes a challenging problem which we need to deal with. The batterieshave a good developing prospect among energy storage system in storing energy such as wind, solar and geothermal energy. One hurdle between the lab-scale experiment and industry-scale application of the advanced batteries is the urgent need for limiting charging capacity degradation and improving cycling stability, known as the shuttle effect in lithium-sulfur batteries or electroosmotic drag coefficient in fuel-cell batteries. The microporous separator between the cathode and anode could be molecular engineered to possessesion selective permeation properties, which can greatly improves the energy efficiency and extends application range of the battery. The present review offers the fundamental fabrication methods of separator film with different material. The review also contains the chemical or physical structure of different materials which are used in making separator film. A table offers the reader a summary of properties such as ionic conductivity, ionic exchange capacity and current density etc.

Cycling Performance of a Columnar-Structured Complex Perovskite in a Temperature Gradient Test

NASA Astrophysics Data System (ADS)

Schlegel, N.; Sebold, D.; Sohn, Y. J.; Mauer, G.; Vaßen, R.

2015-10-01

To increase the efficiency of turbines for the power generation and the aircraft industry, advanced thermal barrier coatings (TBCs) are required. They need to be long-term stable at temperatures higher than 1200 °C. Nowadays, yttria partially stabilized zirconia (YSZ) is applied as standard TBC material. But its long-term application at temperatures higher than 1200 °C leads to detrimental phase changes and sintering effects. Therefore, new materials have to be investigated, for example, complex perovskites. They provide high melting points, high thermal expansion coefficients and thermal conductivities of approx. 2.0 W/(m K). In this work, the complex perovskite La(Al1/4Mg1/2Ta1/4)O3 (LAMT) was investigated. It was deposited by the suspension plasma spraying (SPS) process, resulting in a columnar microstructure of the coating. The coatings were tested in thermal cycling gradient tests and they show excellent results, even though some phase decomposition was found.

a Comprehensive Review of Pansharpening Algorithms for GÖKTÜRK-2 Satellite Images

NASA Astrophysics Data System (ADS)

Kahraman, S.; Ertürk, A.

2017-11-01

In this paper, a comprehensive review and performance evaluation of pansharpening algorithms for GÖKTÜRK-2 images is presented. GÖKTÜRK-2 is the first high resolution remote sensing satellite of Turkey which was designed and built in Turkey, by The Ministry of Defence, TUBITAK-UZAY and Turkish Aerospace Industry (TUSAŞ) collectively. GÖKTÜRK-2 was launched at 18th. December 2012 in Jinguan, China and provides 2.5 meter panchromatic (PAN) and 5 meter multispectral (MS) spatial resolution satellite images. In this study, a large number of pansharpening algorithms are implemented and evaluated for performance on multiple GÖKTÜRK-2 satellite images. Quality assessments are conducted both qualitatively through visual results and quantitatively using Root Mean Square Error (RMSE), Correlation Coefficient (CC), Spectral Angle Mapper (SAM), Erreur Relative Globale Adimensionnelle de Synthése (ERGAS), Peak Signal to Noise Ratio (PSNR), Structural Similarity Index (SSIM) and Universal Image Quality Index (UIQI).

A scheme to calculate higher-order homogenization as applied to micro-acoustic boundary value problems

NASA Astrophysics Data System (ADS)

Vagh, Hardik A.; Baghai-Wadji, Alireza

2008-12-01

Current technological challenges in materials science and high-tech device industry require the solution of boundary value problems (BVPs) involving regions of various scales, e.g. multiple thin layers, fibre-reinforced composites, and nano/micro pores. In most cases straightforward application of standard variational techniques to BVPs of practical relevance necessarily leads to unsatisfactorily ill-conditioned analytical and/or numerical results. To remedy the computational challenges associated with sub-sectional heterogeneities various sophisticated homogenization techniques need to be employed. Homogenization refers to the systematic process of smoothing out the sub-structural heterogeneities, leading to the determination of effective constitutive coefficients. Ordinarily, homogenization involves a sophisticated averaging and asymptotic order analysis to obtain solutions. In the majority of the cases only zero-order terms are constructed due to the complexity of the processes involved. In this paper we propose a constructive scheme for obtaining homogenized solutions involving higher order terms, and thus, guaranteeing higher accuracy and greater robustness of the numerical results. We present

Combined 3D-QSAR modeling and molecular docking study on azacycles CCR5 antagonists

NASA Astrophysics Data System (ADS)

Ji, Yongjun; Shu, Mao; Lin, Yong; Wang, Yuanqiang; Wang, Rui; Hu, Yong; Lin, Zhihua

2013-08-01

The beta chemokine receptor 5 (CCR5) is an attractive target for pharmaceutical industry in the HIV-1, inflammation and cancer therapeutic areas. In this study, we have developed quantitative structure activity relationship (QSAR) models for a series of 41 azacycles CCR5 antagonists using comparative molecular field analysis (CoMFA), comparative molecular similarity indices analysis (CoMSIA), and Topomer CoMFA methods. The cross-validated coefficient q2 values of 3D-QASR (CoMFA, CoMSIA, and Topomer CoMFA) methods were 0.630, 0.758, and 0.852, respectively, the non-cross-validated R2 values were 0.979, 0.978, and 0.990, respectively. Docking studies were also employed to determine the most probable binding mode. 3D contour maps and docking results suggested that bulky groups and electron-withdrawing groups on the core part would decrease antiviral activity. Furthermore, docking results indicated that H-bonds and π bonds were favorable for antiviral activities. Finally, a set of novel derivatives with predicted activities were designed.

Defect detection of helical gears based on time-frequency analysis and using multi-layer fusion network

NASA Astrophysics Data System (ADS)

Ebrahimi Orimi, H.; Esmaeili, M.; Refahi Oskouei, A.; Mirhadizadehd, S. A.; Tse, P. W.

2017-10-01

Condition monitoring of rotary devices such as helical gears is an issue of great significance in industrial projects. This paper introduces a feature extraction method for gear fault diagnosis using wavelet packet due to its higher frequency resolution. During this investigation, the mother wavelet Daubechies 10 (Db-10) was applied to calculate the coefficient entropy of each frequency band of 5th level (32 frequency bands) as features. In this study, the peak value of the signal entropies was selected as applicable features in order to improve frequency band differentiation and reduce feature vectors' dimension. Feature extraction is followed by the fusion network where four different structured multi-layer perceptron networks are trained to classify the recorded signals (healthy/faulty). The robustness of fusion network outputs is greater compared to perceptron networks. The results provided by the fusion network indicate a classification of 98.88 and 97.95% for healthy and faulty classes, respectively.

Fractal dimension analysis for robust ultrasonic non-destructive evaluation (NDE) of coarse grained materials

NASA Astrophysics Data System (ADS)

Li, Minghui; Hayward, Gordon

2018-04-01

Over the recent decades, there has been a growing demand on reliable and robust non-destructive evaluation (NDE) of structures and components made from coarse grained materials such as alloys, stainless steels, carbon-reinforced composites and concrete; however, when inspected using ultrasound, the flaw echoes are usually contaminated by high-level, time-invariant, and correlated grain noise originating from the microstructure and grain boundaries, leading to pretty low signal-to-noise ratio (SNR) and the flaw information being obscured or completely hidden by the grain noise. In this paper, the fractal dimension analysis of the A-scan echoes is investigated as a measure of complexity of the time series to distinguish the echoes originating from the real defects and the grain noise, and then the normalized fractal dimension coefficients are applied to the amplitudes as the weighting factor to enhance the SNR and defect detection. Experiments on industrial samples of the mild steel and the stainless steel are conducted and the results confirm the great benefits of the method.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stoynov, Y.

Functionally graded materials (FGM) are extensively used in modern industry. They are composite materials with continuously varying properties in one or more special dimensions, according to the specific purpose. In view of the wide range of applications of FGM, stress analysis is important for their structural integrity and reliable service life. In this study we will consider functionally graded magneto-electro-elastic materials with one or more cracks subjected to SH waves. We assume that the material properties vary in one and the same way, described by an inhomogeneity function. The boundary value problem is reduced to a system of integro-differential equationsmore » based on the existence of fundamental solutions. Different inhomogeneity classes are used to obtain a wave equation with constant coefficients. Radon transform is applied to derive the fundamental solution in a closed form. Program code in FORTRAN 77 is developed and validated using available examples from literature. Simulations show the dependence of stress field concentration near the crack tips on the frequency of the applied time-harmonic load for different types of material inhomogeneity.« less

An optimization model for regional air pollutants mitigation based on the economic structure adjustment and multiple measures: A case study in Urumqi city, China.

PubMed

Sun, Xiaowei; Li, Wei; Xie, Yulei; Huang, Guohe; Dong, Changjuan; Yin, Jianguang

2016-11-01

A model based on economic structure adjustment and pollutants mitigation was proposed and applied in Urumqi. Best-worst case analysis and scenarios analysis were performed in the model to guarantee the parameters accuracy, and to analyze the effect of changes of emission reduction styles. Results indicated that pollutant-mitigations of electric power industry, iron and steel industry, and traffic relied mainly on technological transformation measures, engineering transformation measures and structure emission reduction measures, respectively; Pollutant-mitigations of cement industry relied mainly on structure emission reduction measures and technological transformation measures; Pollutant-mitigations of thermal industry relied mainly on the four mitigation measures. They also indicated that structure emission reduction was a better measure for pollutants mitigation of Urumqi. Iron and steel industry contributed greatly in SO2, NOx and PM (particulate matters) emission reduction and should be given special attention in pollutants emission reduction. In addition, the scales of iron and steel industry should be reduced with the decrease of SO2 mitigation amounts. The scales of traffic and electric power industry should be reduced with the decrease of NOx mitigation amounts, and the scales of cement industry and iron and steel industry should be reduced with the decrease of PM mitigation amounts. The study can provide references of pollutants mitigation schemes to decision-makers for regional economic and environmental development in the 12th Five-Year Plan on National Economic and Social Development of Urumqi. Copyright © 2016 Elsevier Ltd. All rights reserved.

Optical properties of an industrial fire observed with a ground based N2-Raman lidar over the Paris area

NASA Astrophysics Data System (ADS)

Shang, Xiaoxia; Chazette, Patrick; Totems, Julien

2018-04-01

This paper presents the first, to our knowledge, lidar measurement of an industrial fire plume, which covered the north of the Paris area on 17th April 2015. The fire started in a textile warehouse and rapidly spread by emitting large quantities of aerosols into the low troposphere. A ground based N2-Raman lidar performed continuous measurements during this event. Vertical profiles of the aerosol extinction coefficient, depolarization and lidar ratio are derived. A Monte Carlo algorithm was used to assess the uncertainties on the optical parameters, and to evaluate lidar inversion methods.

Plastic optical fibre sensor for quality control in food industry

NASA Astrophysics Data System (ADS)

Novo, C.; Bilro, L.; Ferreira, R.; Alberto, N.; Antunes, P.; Leitão, C.; Nogueira, R.; Pinto, J. L.

2013-05-01

The present work addresses the need for new devices felt in the context of quality control, especially in the food industry. Due to the spectral dependence of the attenuation coefficient, a novel dual-parameter sensor for colour and refractive index was developed and tested. The sensor employs plastic optical fibres to measure the transmitted optical power in three measurement cells each with a different incident wavelength. The performance of the sensor was tested using several dyes at different concentrations and aqueous solutions of glycerine and ethanol. Results show that this technique allows the monitoring of refractive index and colour without cross-sensitivity.

THz wave sensing for petroleum industrial applications

NASA Astrophysics Data System (ADS)

Al-Douseri, Fatemah M.; Chen, Yunqing; Zhang, X.-C.

2006-04-01

We present the results of terahertz (THz) sensing of gasoline products. The frequency-dependent absorption coefficients, refractive indices, and complex dielectric constants of gasoline and xylene isomers were extracted in the spectral range from 0.5 3.0 THz. The THz spectra of gasoline (#87, #89, #93) and related BTEX (benzene, toluene, ethylbenzene, and xylene) compounds were studied by using Fourier transform infrared spectroscopy (FTIR) in the 1.5 20 THz (50 660 cm-1). The xylene isomers, which are used as antiknock agent in gasoline were determined quantitatively in gasoline in the THz range. Our investigations show the potential of THz technology for the petroleum industrial applications.

Development of uncertainty-based work injury model using Bayesian structural equation modelling.

PubMed

Chatterjee, Snehamoy

2014-01-01

This paper proposed a Bayesian method-based structural equation model (SEM) of miners' work injury for an underground coal mine in India. The environmental and behavioural variables for work injury were identified and causal relationships were developed. For Bayesian modelling, prior distributions of SEM parameters are necessary to develop the model. In this paper, two approaches were adopted to obtain prior distribution for factor loading parameters and structural parameters of SEM. In the first approach, the prior distributions were considered as a fixed distribution function with specific parameter values, whereas, in the second approach, prior distributions of the parameters were generated from experts' opinions. The posterior distributions of these parameters were obtained by applying Bayesian rule. The Markov Chain Monte Carlo sampling in the form Gibbs sampling was applied for sampling from the posterior distribution. The results revealed that all coefficients of structural and measurement model parameters are statistically significant in experts' opinion-based priors, whereas, two coefficients are not statistically significant when fixed prior-based distributions are applied. The error statistics reveals that Bayesian structural model provides reasonably good fit of work injury with high coefficient of determination (0.91) and less mean squared error as compared to traditional SEM.

Simulation of the dissolved nitrogen and phosphorus loads in different land uses in the Three Gorges Reservoir Region--based on the improved export coefficient model.

PubMed

Wang, Jinliang; Shao, Jing'an; Wang, Dan; Ni, Jiupai; Xie, Deti

2015-11-01

Nonpoint source pollution is one of the primary causes of eutrophication of water bodies. The concentrations and loads of dissolved pollutants have a direct bearing on the environmental quality of receiving water bodies. Based on the Johnes export coefficient model, a pollutant production coefficient was established by introducing the topographical index and measurements of annual rainfall. A pollutant interception coefficient was constructed by considering the width and slope of present vegetation. These two coefficients were then used as the weighting factors to modify the existing export coefficients of various land uses. A modified export coefficient model was created to estimate the dissolved nitrogen and phosphorus loads in different land uses in the Three Gorges Reservoir Region (TGRR) in 1990, 1995, 2000, 2005, and 2010. The results show that the new land use export coefficient was established by the modification of the production pollution coefficient and interception pollution coefficient. This modification changed the single numerical structure of the original land use export coefficient and takes into consideration temporal and spatial differentiation features. The modified export coefficient retained the change structure of the original single land use export coefficient, and also demonstrated that the land use export coefficient was not only impacted by the change of land use itself, but was also influenced by other objective conditions, such as the characteristics of the underlying surface, amount of rainfall, and the overall presence of vegetation. In the five analyzed years, the simulation values of the dissolved nitrogen and phosphorus loads in paddy fields increased after applying the modification in calculation. The dissolved nitrogen and phosphorus loads in dry land comprised the largest proportions of the TGRR's totals. After modification, the dry land values showed an initial increase and then a decrease over time, but the increments were much smaller than those of the paddy field. The dissolved nitrogen and phosphorus loads in the woodland and meadow decreased after modification. The dissolved nitrogen and phosphorus loads in the building lot were the lowest but showed an increase with the progression of time. These results demonstrate that the modified export coefficient model significantly improves the accuracy of dissolved pollutant load simulation for different land uses in the TGRR, especially the accuracy of dissolved nitrogen load simulation.

A Review of International Telecommunications Industry Issues, Structure, and Regulatory Problems.

ERIC Educational Resources Information Center

Cole, Jack E.; And Others

Industry structure studies prior to 1968 are briefly reviewed, and an overview of industrial and technological developments up to the present is provided through synopses of more recent studies. Areas covered include overseas telephone and record carriers; the creation of the Communications Satellite Corporation; the current regulatory and…

Absorption and recovery of n-hexane in aqueous solutions of fluorocarbon surfactants.

PubMed

Xiao, Xiao; Yan, Bo; Fu, Jiamo; Xiao, Xianming

2015-11-01

n-Hexane is widely used in industrial production as an organic solvent. As an industrial exhaust gas, the contribution of n-hexane to air pollution and damage to human health are attracting increasing attention. In the present study, aqueous solutions of two fluorocarbon surfactants (FSN100 and FSO100) were investigated for their properties of solubilization and dynamic absorption of n-hexane, as well as their capacity for regeneration and n-hexane recovery by thermal distillation. The results show that the two fluorocarbon surfactants enhance dissolution and absorption of n-hexane, and their effectiveness is closely related to their concentrations in solution. For low concentration solutions (0.01%-0.30%), the partition coefficient decreases dramatically and the saturation capacity increases significantly with increasing concentration, but the changes for both are more modest when the concentration is over 0.30%. The FSO100 solution presents a smaller partition coefficient and a greater saturation capacity than the FSN100 solution at the same concentration, indicating a stronger solubilization for n-hexane. Thermal distillation is a feasible method to recover n-hexane from these absorption solutions, and to regenerate them. With 90sec heating at 80-85°C, the recovery of n-hexane ranges between 81% and 85%, and the regenerated absorption solution maintains its original performance during reuse. This study provides basic information on two fluorocarbon surfactants for application in the treatment of industrial n-hexane waste gases. Copyright © 2015. Published by Elsevier B.V.

Does network topology influence systemic risk contribution? A perspective from the industry indices in Chinese stock market

PubMed Central

Long, Haiming; Tang, Nengyu

2017-01-01

This study considers the effect of an industry’s network topology on its systemic risk contribution to the stock market using data from the CSI 300 two-tier industry indices from the Chinese stock market. We first measure industry’s conditional-value-at-risk (CoVaR) and the systemic risk contribution (ΔCoVaR) using the fitted time-varying t-copula function. The network of the stock industry is established based on dynamic conditional correlations with the minimum spanning tree. Then, we investigate the connection characteristics and topology of the network. Finally, we utilize seemingly unrelated regression estimation (SUR) of panel data to analyze the relationship between network topology of the stock industry and the industry’s systemic risk contribution. The results show that the systemic risk contribution of small-scale industries such as real estate, food and beverage, software services, and durable goods and clothing, is higher than that of large-scale industries, such as banking, insurance and energy. Industries with large betweenness centrality, closeness centrality, and clustering coefficient and small node occupancy layer are associated with greater systemic risk contribution. In addition, further analysis using a threshold model confirms that the results are robust. PMID:28683130

Application of an efficient hybrid scheme for aeroelastic analysis of advanced propellers

NASA Technical Reports Server (NTRS)

Srivastava, R.; Sankar, N. L.; Reddy, T. S. R.; Huff, D. L.

1989-01-01

An efficient 3-D hybrid scheme is applied for solving Euler equations to analyze advanced propellers. The scheme treats the spanwise direction semi-explicitly and the other two directions implicitly, without affecting the accuracy, as compared to a fully implicit scheme. This leads to a reduction in computer time and memory requirement. The calculated power coefficients for two advanced propellers, SR3 and SR7L, and various advanced ratios showed good correlation with experiment. Spanwise distribution of elemental power coefficient and steady pressure coefficient differences also showed good agreement with experiment. A study of the effect of structural flexibility on the performance of the advanced propellers showed that structural deformation due to centrifugal and aero loading should be included for better correlation.

Cross-Correlations and Structures of Aero-Engine Gas Path System Based on DCCA Coefficient and Rooted Tree

NASA Astrophysics Data System (ADS)

Dong, Keqiang; Fan, Jie; Gao, You

2015-12-01

Identifying the mutual interaction is a crucial problem that facilitates the understanding of emerging structures in complex system. We here focus on aero-engine dynamic as an example of complex system. By applying the detrended cross-correlation analysis (DCCA) coefficient method to aero-engine gas path system, we find that the low-spool rotor speed (N1) and high-spool rotor speed (N2) fluctuation series exhibit cross-correlation characteristic. Further, we employ detrended cross-correlation coefficient matrix and rooted tree to investigate the mutual interactions of other gas path variables. The results can infer that the exhaust gas temperature (EGT), N1, N2, fuel flow (WF) and engine pressure ratio (EPR) are main gas path parameters.

Protic ammonium carboxylate ionic liquids: insight into structure, dynamics and thermophysical properties by alkyl group functionalization.

PubMed

Reddy, Th Dhileep N; Mallik, Bhabani S

2017-04-19

This study is aimed at characterising the structure, dynamics and thermophysical properties of five alkylammonium carboxylate ionic liquids (ILs) from classical molecular dynamics simulations. The structural features of these ILs were characterised by calculating the site-site radial distribution functions, g(r), spatial distribution functions and structure factors. The structural properties demonstrate that ILs show greater interaction between cations and anions when alkyl chain length increases on the cation or anion. In all ILs, spatial distribution functions show that the anion is close to the acidic hydrogen atoms of the ammonium cation. We determined the role of alkyl group functionalization of the charged entities, cations and anions, in the dynamical behavior and the transport coefficients of this family of ionic liquids. The dynamics of ILs are described by studying the mean square displacement (MSD) of the centres of mass of the ions, diffusion coefficients, ionic conductivities and hydrogen bonds as well as residence dynamics. The diffusion coefficients and ionic conductivity decrease with an increase in the size of the cation or anion. The effect of alkyl chain length on ionic conductivity calculated in this article is consistent with the findings of other experimental studies. Hydrogen bond lifetimes and residence times along with structure factors were also calculated, and are related to alkyl chain length.

Spatial characteristics of cadmium in topsoils in a typical e-waste recycling area in southeast China and its potential threat to shallow groundwater.

PubMed

Wu, Chunfa; Luo, Yongming; Deng, Shaopo; Teng, Ying; Song, Jing

2014-02-15

Informal electrical and electronic waste (e-waste) recycling often creates secondary sources of cadmium (Cd) pollution. To characterize the total Cd concentration (Cdtotal) in topsoil and evaluate the threat of Cd in topsoils to shallow groundwater, 187 topsoil samples and 12 shallow groundwater samples were collected in a typical e-waste recycling area in southeast China. Soil organic matter content, soil pH and Cdtotal in topsoil, pH and dissolved Cd concentration in shallow groundwater were measured. Cdtotal in the topsoils showed an inverse distribution trend with soil pH in that high Cd concentrations (and low pH values) were found in the surrounding area of the metal recycling industrial park where there were many family-operated e-waste recycling facilities before the industrial park was established and with low concentrations (and high pH values) in other areas, and they had similar spatial correlation structures. Cd accumulation and acidification were synchronous in topsoils, and soil pH was significantly correlated with Cdtotal in topsoils with low to moderate negative correlation coefficient (r=-0.24), indicating that both of them maybe correlated with informal recycling. The shallow groundwater in the surrounding area of the metal recycling industrial park was seriously contaminated by Cd, and topsoil Cd accumulation and acidification in the surrounding area of e-waste recycling sites significantly increase the risk of shallow groundwater contaminated by Cd. Action is urgently required to control Cd accumulation and acidification by improving the recycling operations of e-wastes in order to reduce the risk of Cd leaching from topsoils and shallow groundwater contamination. Copyright © 2013. Published by Elsevier B.V.

Spatial and temporal dynamics of agricultural residue resources in the last 30 years in China.

PubMed

Yang, Yanli; Zhang, Peidong; Yang, Xutong; Xu, Xiaoning

2016-12-01

The availability and distribution of biomass resources are important for the development of the bioenergy industry in a region. Biomass resources are abundant in China; however, the raw material is severely deficient, which makes the Chinese bioenergy industry an embarrassment and a contradiction. Unclear reserves and distribution and changing trends of biomass resources are the reason for this situation. A collection coefficient model of Chinese agricultural residue resources was established and the spatial and temporal pattern dynamics of agricultural residue resources in the last 30 years were analyzed. The results show that agricultural residue resources increased in stages from 1978 to 2011, including a rapid increase from 1978 to 1999, a significant fall from 2000 to 2004, and a slow increase from 2004 to 2011. Crops straw and livestock manure are the main ingredients of agricultural residue resources with proportions of 53-59% and 31-38%, respectively. However, the former has gradually decreased, while the latter is increasing. This mainly resulted from the strategic reorganization of the Chinese agriculture structure and the rapid development of large-scale livestock breeding and agricultural mechanization. Large regional differences existed in Chinese agricultural residue resources, and three distribution types formed, including resource-rich areas in North China, Northeast and Inner Mongolia, resource-limited areas in Central and Southwest China, and resource-poor areas along Northwest and Southeast coasts. This pattern is a reverse of the distributions of climatic conditions, water resources, economic development, human resources, and technological levels. Finally, it can be predicted that livestock manure and biomass conversion technology at low temperature will play increasingly significant roles in bioenergy industry development. © The Author(s) 2016.

Effect of silicide/silicon hetero-junction structure on thermal conductivity and Seebeck coefficient.

PubMed

Choi, Wonchul; Park, Young-Sam; Hyun, Younghoon; Zyung, Taehyoung; Kim, Jaehyeon; Kim, Soojung; Jeon, Hyojin; Shin, Mincheol; Jang, Moongyu

2013-12-01

We fabricated a thermoelectric device with a silicide/silicon laminated hetero-structure by using RF sputtering and rapid thermal annealing. The device was observed to have Ohmic characteristics by I-V measurement. The temperature differences and Seebeck coefficients of the proposed silicide/silicon laminated and bulk structure were measured. The laminated thermoelectric device shows suppression of heat flow from the hot to cold side. This is supported by the theory that the atomic mass difference between silicide and silicon creates a scattering center for phonons. The major impact of our work is that phonon transmission is suppressed at the interface between silicide and silicon without degrading electrical conductivity. The estimated thermal conductivity of the 3-layer laminated device is 126.2 +/- 3.7 W/m. K. Thus, by using the 3-layer laminated structure, thermal conductivity is reduced by around 16% compared to bulk silicon. However, the Seebeck coefficient of the thermoelectric device is degraded compared to that of bulk silicon. It is understood that electrical conductivity is improved by using silicide as a scattering center.

Electronic Structure, Optical and Transport Properties of Double Perovskite La2NbMnO6: A Theoretical Understanding from DFT Calculations

NASA Astrophysics Data System (ADS)

Parrey, Khursheed Ahmad; Khandy, Shakeel Ahmad; Islam, Ishtihadah; Laref, Amel; Gupta, Dinesh C.; Niazi, Asad; Aziz, Anver; Ansari, S. G.; Khenata, R.; Rubab, Seemin

2018-03-01

Double perovskite La2NbMnO6 was systematically studied using the first-principles calculations. The structural, electronic, optical and transport properties of this compound were calculated. Spin resolved band structure predicted this material as a half-metal with an energy gap of 3.75 eV in spin down state. The optical coefficients including optical conductivity, reflectivity and electron energy loss are calculated for photon energy up to 30.00 eV to understand the optical response of this perovskite. The strong absorption of all the ultraviolet and infrared frequencies of the spectrum by this material may suggest the potential application of this material for the optoelectronic devices in ultraviolet and infra-red region. Also, the thermoelectric properties with a speculation from the half-metallic electronic structure are reported. Subsequently, the Seebeck coefficient, electrical and thermal conductivity coefficients are calculated to predict the thermoelectric figure of merit (zT), the maximum of which is found out to be 0.14 at 800 K.

XRD- and infrared-probed anisotropic thermal expansion properties of an organic semiconducting single crystal.

PubMed

Mohanraj, J; Capria, E; Benevoli, L; Perucchi, A; Demitri, N; Fraleoni-Morgera, A

2018-01-17

The anisotropic thermal expansion properties of an organic semiconducting single crystal constituted by 4-hydroxycyanobenzene (4HCB) have been probed by XRD in the range 120-300 K. The anisotropic thermal expansion coefficients for the three crystallographic axes and for the crystal volume have been determined. A careful analysis of the crystal structure revealed that the two different H-bonds stemming from the two independent, differently oriented 4HCB molecules composing the unit cell have different rearrangement patterns upon temperature variations, in terms of both bond length and bond angle. Linearly Polarized Mid InfraRed (LP-MIR) measurements carried out in the same temperature range, focused on the O-H bond spectral region, confirm this finding. The same LP-MIR measurements, on the basis of a semi-empirical relation and of geometrical considerations and assumptions, allowed calculation of the -CNH-O- hydrogen bond length along the a and b axes of the crystal. In turn, the so-calculated -CNH-O- bond lengths were used to derive the thermal expansion coefficients along the corresponding crystal axes, as well as the volumetric one, using just the LP-MIR data. Reasonable to good agreement with the same values obtained from XRD measurements was obtained. This proof-of-principle opens interesting perspectives about the possible development of a rapid, low cost and industry-friendly assessment of the thermal expansion properties of organic semiconducting single crystals (OSSCs) involving hydrogen bonds.

Revealing mesoscopic structural universality with diffusion

PubMed Central

Novikov, Dmitry S.; Jensen, Jens H.; Helpern, Joseph A.; Fieremans, Els

2014-01-01

Measuring molecular diffusion is widely used for characterizing materials and living organisms noninvasively. This characterization relies on relations between macroscopic diffusion metrics and structure at the mesoscopic scale commensurate with the diffusion length. Establishing such relations remains a fundamental challenge, hindering progress in materials science, porous media, and biomedical imaging. Here we show that the dynamical exponent in the time dependence of the diffusion coefficient distinguishes between the universality classes of the mesoscopic structural complexity. Our approach enables the interpretation of diffusion measurements by objectively selecting and modeling the most relevant structural features. As an example, the specific values of the dynamical exponent allow us to identify the relevant mesoscopic structure affecting MRI-measured water diffusion in muscles and in brain, and to elucidate the structural changes behind the decrease of diffusion coefficient in ischemic stroke. PMID:24706873

Development of TLSER model and QSAR model for predicting partition coefficients of hydrophobic organic chemicals between low density polyethylene film and water.

PubMed

Liu, Huihui; Wei, Mengbi; Yang, Xianhai; Yin, Cen; He, Xiao

2017-01-01

Partition coefficients are vital parameters for measuring accurately the chemicals concentrations by passive sampling devices. Given the wide use of low density polyethylene (LDPE) film in passive sampling, we developed a theoretical linear solvation energy relationship (TLSER) model and a quantitative structure-activity relationship (QSAR) model for the prediction of the partition coefficient of chemicals between LDPE and water (K pew ). For chemicals with the octanol-water partition coefficient (log K ow ) <8, a TLSER model with V x (McGowan volume) and qA - (the most negative charge on O, N, S, X atoms) as descriptors was developed, but the model had relatively low determination coefficient (R 2 ) and cross-validated coefficient (Q 2 ). In order to further explore the theoretical mechanisms involved in the partition process, a QSAR model with four descriptors (MLOGP (Moriguchi octanol-water partition coeff.), P_VSA_s_3 (P_VSA-like on I-state, bin 3), Hy (hydrophilic factor) and NssO (number of atoms of type ssO)) was established, and statistical analysis indicated that the model had satisfactory goodness-of-fit, robustness and predictive ability. For chemicals with log K OW >8, a TLSER model with V x and a QSAR model with MLOGP as descriptor were developed. This is the first paper to explore the models for highly hydrophobic chemicals. The applicability domain of the models, characterized by the Euclidean distance-based method and Williams plot, covered a large number of structurally diverse chemicals, which included nearly all the common hydrophobic organic compounds. Additionally, through mechanism interpretation, we explored the structural features those governing the partition behavior of chemicals between LDPE and water. Copyright © 2016 Elsevier B.V. All rights reserved.

Relaxation of structural parameters and potential coefficients of nonrigid molecules. General symmetry properties and application to ab initio study of 1,2-difluoroethane

NASA Astrophysics Data System (ADS)

Ha, T.-K.; Günthard, H. H.

1989-07-01

Structural parameters like bond length, bond angles, etc. and harmonic and anharmonic potential coefficients of molecules with internal rotation, inversion or puckering modes are generally assumed to vary with the large amplitude internal coordinates in a concerted manner (relaxation). Taking the coordinate vectors of the nuclear configuration of semirigid molecules with relaxation (SRMRs) as functions of relaxing structural parameters and finite amplitude internal coordinate, the isometric group of SRMRs is discussed and the irreducible representations of the latter are shown to classify into engendered and nonengendered ones. On this basis a concept of equivalent sets of nuclei SRMRs is introduced and an analytical expression is derived which defines the most general functional form of relaxation increments of all common types of structural parameters compatible with isometric symmetry. This formula is shown to be a close analog of an analytical expression defining the transformations induced by the isometric group of infinitesimal internal coordinates associated with typical structural parameters. Furthermore analogous formulae are given for the most general form of the relaxation of harmonic potential coefficients as a function of finite internal coordinates. The general relations are illustrated by ab initio calculations for 1,2-difluoroethane at the MP4/DZP//HF/4-31G* level for twelve values of the dihedral angle including complete structure optimization. The potential to internal rotation is found to be in essential agreement with experimentally derived data. For a complete set of ab initio structural parameters the associated relaxation increments are represented as Fourier series, which are shown to confirm the form predicted by the general formula and the isometric group of 1,2-difluoroethane. Depending on type of the structural parameters (bond length, bond angles, etc.), the associated relaxation increments appear to follow some simple rules. Similarly a complete set of harmonic potential coefficients derived from the ab initio calculations will be analyzed in terms of Fourier series and shown to conform to the symmetry requirements of the symmetry group. Relaxation of potential coefficients is found to amount to up to ≈5% for some types of diagonal and nondiagonal terms and to reflect certain "topological" rules similar to regularities of harmonic potential constants of quasi-rigid molecules found in empirical determinations of valence force fields.

Algae in the assessment of industrial effluents: case study in Southern Bengal, India.

PubMed

Sen Sarkar, Neera; Bandyopadhyaya, Tuli; Datta, Shilpa; Das, Swapna

2013-01-01

This article is an assessment of the diversity of scum and bloom algae encountered in different industrial effluents of Southern Bengal, India, analyzing their habitat and correlating the habitat ecology of each study site. The study was conducted during the period May 2009 to August 2010. The study sites include effluent release areas of the dairy industry, a distillery unit, the leather industry, and an herbal medicine unit. Habitat were analyzed for pH, dissolved oxygen, biological oxygen demand, salinity, alkalinity, and phosphate and nitrate levels. Correlation coefficients were calculated for habitat parameters and algae encountered, showing a significant positive correlation between the richness of dominant and subdominant species with biochemical oxygen demand and salinity and a significant negative correlation with alkalinity, phosphates, and the nitrate-to-phosphate ratio. The richness of dominant and subdominant species in the effluent discharge areas show average values of 9 and 5 in the distillery unit, 8 and 5 in the dairy industry, 7 and 8 in the leather industry, and 5 and 9 in the herbal medicine unit, respectively, with a few (ranging between 3 and 7) co-occurring species in each case. The algal groups encountered were cyanobacteria, euglenophytes, chlorophytes, and bacillariophytes, showing Palmer's Algal Pollution Index of 15 in the dairy industry, 20 in the distillery unit, 28 in the leather industry, and 8 in the herbal medicine unit.

Estimates of emergency operating capacity in U.S. manufacturing industries: 1994--2005

DOE Office of Scientific and Technical Information (OSTI.GOV)

Belzer, D.B.

1997-02-01

To develop integrated policies for mobilization preparedness, planners require estimates and projections of available productive capacity during national emergency conditions. This report develops projections of national emergency operating capacity (EOC) for 458 US manufacturing industries at the 4-digit Standard Industrial Classification (SIC) level. These measures are intended for use in planning models that are designed to predict the demands for detailed industry sectors that would occur under conditions such as a military mobilization or a major national disaster. This report is part of an ongoing series of studies prepared by the Pacific Northwest National Laboratory to support mobilization planning studiesmore » of the Federal Emergency Planning Agency/US Department of Defense (FEMA/DOD). Earlier sets of EOC estimates were developed in 1985 and 1991. This study presents estimates of EOC through 2005. As in the 1991 study, projections of capacity were based upon extrapolations of equipment capital stocks. The methodology uses time series regression models based on industry data to obtain a response function of industry capital stock to levels of industrial output. The distributed lag coefficients of these response function are then used with projected outputs to extrapolate the 1994 level of EOC. Projections of industrial outputs were taken from the intermediate-term forecast of the US economy prepared by INFORUM (Interindustry Forecasting Model, University of Maryland) in the spring of 1996.« less

Simulation and experimental study of a novel bifacial structure of silicon heterojunction solar cell for high efficiency and low cost

NASA Astrophysics Data System (ADS)

Huang, Haibin; Tian, Gangyu; Zhou, Lang; Yuan, Jiren; Fahrner, Wolfgang R.; Zhang, Wenbin; Li, Xingbing; Chen, Wenhao; Liu, Renzhong

2018-03-01

A novel structure of Ag grid/SiN x /n+-c-Si/n-c-Si/i-a-Si:H/p+-a-Si:H/TCO/Ag grid was designed to increase the efficiency of bifacial amorphous/crystalline silicon-based solar cells and reduce the rear material consumption and production cost. The simulation results show that the new structure obtains higher efficiency compared with the typical bifacial amorphous/crystalline silicon-based solar cell because of an increase in the short-circuit current (J sc), while retaining the advantages of a high open-circuit voltage, low temperature coefficient, and good weak-light performance. Moreover, real cells composed of the novel structure with dimensions of 75 mm ×75 mm were fabricated by a special fabrication recipe based on industrial processes. Without parameter optimization, the cell efficiency reached 21.1% with the J sc of 41.7 mA/cm2. In addition, the novel structure attained 28.55% potential conversion efficiency under an illumination of AM 1.5 G, 100 mW/cm2. We conclude that the configuration of the Ag grid/SiN x /n+-c-Si/n-c-Si/i-a-Si:H/p+-a-Si:H/TCO/Ag grid is a promising structure for high efficiency and low cost. Project supported by the Jiangxi Provincial Key Research and Development Foundation, China (Grant No. 2016BBH80043), the Open Fund of Jiangsu Key Laboratory of Materials and Technology for Energy Conversion, China (Grant No. NJ20160032), and the National Natural Science Foundation of China (Grant Nos. 61741404, 61464007, and 51561022).

Effects of surface roughness and absorption on light propagation in graded-profile waveguides

DOE Office of Scientific and Technical Information (OSTI.GOV)

Danilenko, S S; Osovitskii, A N

2011-06-30

This paper examines the effects of surface roughness and absorption on laser light propagation in graded-profile waveguiding structures. We derive analytical expressions for the scattering and absorption coefficients of guided waves and analyse these coefficients in relation to parameters of the waveguiding structure and the roughness of its boundary. A new approach is proposed to measuring roughness parameters of precision dielectric surfaces. Experimental evidence is presented which supports the main conclusions of the theory. (integraled-optical waweguides)

Production process stability - core assumption of INDUSTRY 4.0 concept

NASA Astrophysics Data System (ADS)

Chromjakova, F.; Bobak, R.; Hrusecka, D.

2017-06-01

Today’s industrial enterprises are confronted by implementation of INDUSTRY 4.0 concept with basic problem - stabilised manufacturing and supporting processes. Through this phenomenon of stabilisation, they will achieve positive digital management of both processes and continuously throughput. There is required structural stability of horizontal (business) and vertical (digitized) manufacturing processes, supported through digitalised technologies of INDUSTRY 4.0 concept. Results presented in this paper based on the research results and survey realised in more industrial companies. Following will described basic model for structural process stabilisation in manufacturing environment.

Study of Manpower Requirements by Occupation for Alternative Technologies in the Energy-Related Industries, 1970-1990. Volumes I, IIA, and III.

ERIC Educational Resources Information Center

Gutmanis, Ivars; And Others

The report presents the methodology used by the National Planning Association (NPA), under contract to the Federal Energy Administration (FEA), to estimate direct labor usage coefficients in some sixty different occupational categories involved in construction, operation, and maintenance of energy facilities. Volume 1 presents direct labor usage…

49 CFR Appendix C to Part 238 - Suspension System Safety Performance Standards

Code of Federal Regulations, 2011 CFR

2011-10-01

... 49 Transportation 4 2011-10-01 2011-10-01 false Suspension System Safety Performance Standards C... industry standard acceptable to FRA is developed and approved under the procedures provided in § 238.21. (a... as follows: ER12MY99.005 where: δ=flange angle (deg). μ=coefficient of friction of 0.5. (2) The net...

49 CFR Appendix C to Part 238 - Suspension System Safety Performance Standards

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 4 2012-10-01 2012-10-01 false Suspension System Safety Performance Standards C... industry standard acceptable to FRA is developed and approved under the procedures provided in § 238.21. (a... as follows: ER12MY99.005 where: δ=flange angle (deg). μ=coefficient of friction of 0.5. (2) The net...

75 FR 52755 - Draft Guidance for Industry on Acute Bacterial Skin and Skin Structure Infections: Developing...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-27

...] Draft Guidance for Industry on Acute Bacterial Skin and Skin Structure Infections: Developing Drugs for... ``Acute Bacterial Skin and Skin Structure Infections: Developing Drugs for Treatment.'' The purpose of... antimicrobial drugs for the treatment of acute bacterial skin and skin structure infections (ABSSSI), impetigo...

Piezoelectric shear wave resonator and method of making same

DOEpatents

Wang, Jin S.; Lakin, Kenneth M.; Landin, Allen R.

1988-01-01

An acoustic shear wave resonator comprising a piezoelectric film having its C-axis substantially inclined from the film normal such that the shear wave coupling coefficient significantly exceeds the longitudinal wave coupling coefficient, whereby the film is capable of shear wave resonance, and means for exciting said film to resonate. The film is prepared by deposition in a dc planar magnetron sputtering system to which a supplemental electric field is applied. The resonator structure may also include a semiconductor material having a positive temperature coefficient of resonance such that the resonator has a temperature coefficient of resonance approaching 0 ppm/.degree.C.

Method of making a piezoelectric shear wave resonator

DOEpatents

Wang, Jin S.; Lakin, Kenneth M.; Landin, Allen R.

1987-02-03

An acoustic shear wave resonator comprising a piezoelectric film having its C-axis substantially inclined from the film normal such that the shear wave coupling coefficient significantly exceeds the longitudinal wave coupling coefficient, whereby the film is capable of shear wave resonance, and means for exciting said film to resonate. The film is prepared by deposition in a dc planar magnetron sputtering system to which a supplemental electric field is applied. The resonator structure may also include a semiconductor material having a positive temperature coefficient of resonance such that the resonator has a temperature coefficient of resonance approaching 0 ppm/.degree.C.

Piezoelectric coefficients of bulk 3R transition metal dichalcogenides

NASA Astrophysics Data System (ADS)

Konabe, Satoru; Yamamoto, Takahiro

2017-09-01

The piezoelectric properties of bulk transition metal dichalcogenides (TMDCs) with a 3R structure were investigated using first-principles calculations based on density functional theory combined with the Berry phase treatment. Values for the elastic constant Cijkl , the piezoelectric coefficient eijk , and the piezoelectric coefficient dijk are given for bulk 3R-TMDCs (MoS2, MoSe2, WS2, and WSe2). The piezoelectric coefficients of bulk 3R-TMDCs are shown to be sufficiently large or comparable to those of conventional bulk piezoelectric materials such as α-quartz, wurtzite GaN, and wurtzite AlN.

Wavelength and energy dependent absorption of unconventional fuel mixtures

NASA Astrophysics Data System (ADS)

Khan, N.; Saleem, Z.; Mirza, A. A.

2005-11-01

Economic considerations of laser induced ignition over the normal electrical ignition of direct injected Compressed Natural Gas (CNG) engines has motivated automobile industry to go for extensive research on basic characteristics of leaner unconventional fuel mixtures to evaluate practical possibility of switching over to the emerging technologies. This paper briefly reviews the ongoing research activities on minimum ignition energy and power requirements of natural gas fuels and reports results of present laser air/CNG mixture absorption coefficient study. This study was arranged to determine the thermo-optical characteristics of high air/fuel ratio mixtures using laser techniques. We measured the absorption coefficient using four lasers of multiple wavelengths over a wide range of temperatures and pressures. The absorption coefficient of mixture was found to vary significantly over change of mixture temperature and probe laser wavelengths. The absorption coefficients of air/CNG mixtures were measured using 20 watts CW/pulsed CO2 laser at 10.6μm, Pulsed Nd:Yag laser at 1.06μm, 532 nm (2nd harmonic) and 4 mW CW HeNe laser at 645 nm and 580 nm for temperatures varying from 290 to 1000K using optical transmission loss technique.

A 3D-CFD code for accurate prediction of fluid flows and fluid forces in seals

NASA Technical Reports Server (NTRS)

Athavale, M. M.; Przekwas, A. J.; Hendricks, R. C.

1994-01-01

Current and future turbomachinery requires advanced seal configurations to control leakage, inhibit mixing of incompatible fluids and to control the rotodynamic response. In recognition of a deficiency in the existing predictive methodology for seals, a seven year effort was established in 1990 by NASA's Office of Aeronautics Exploration and Technology, under the Earth-to-Orbit Propulsion program, to develop validated Computational Fluid Dynamics (CFD) concepts, codes and analyses for seals. The effort will provide NASA and the U.S. Aerospace Industry with advanced CFD scientific codes and industrial codes for analyzing and designing turbomachinery seals. An advanced 3D CFD cylindrical seal code has been developed, incorporating state-of-the-art computational methodology for flow analysis in straight, tapered and stepped seals. Relevant computational features of the code include: stationary/rotating coordinates, cylindrical and general Body Fitted Coordinates (BFC) systems, high order differencing schemes, colocated variable arrangement, advanced turbulence models, incompressible/compressible flows, and moving grids. This paper presents the current status of code development, code demonstration for predicting rotordynamic coefficients, numerical parametric study of entrance loss coefficients for generic annular seals, and plans for code extensions to labyrinth, damping, and other seal configurations.

Multi-charge-state molecular dynamics and self-diffusion coefficient in the warm dense matter regime

NASA Astrophysics Data System (ADS)

Fu, Yongsheng; Hou, Yong; Kang, Dongdong; Gao, Cheng; Jin, Fengtao; Yuan, Jianmin

2018-01-01

We present a multi-ion molecular dynamics (MIMD) simulation and apply it to calculating the self-diffusion coefficients of ions with different charge-states in the warm dense matter (WDM) regime. First, the method is used for the self-consistent calculation of electron structures of different charge-state ions in the ion sphere, with the ion-sphere radii being determined by the plasma density and the ion charges. The ionic fraction is then obtained by solving the Saha equation, taking account of interactions among different charge-state ions in the system, and ion-ion pair potentials are computed using the modified Gordon-Kim method in the framework of temperature-dependent density functional theory on the basis of the electron structures. Finally, MIMD is used to calculate ionic self-diffusion coefficients from the velocity correlation function according to the Green-Kubo relation. A comparison with the results of the average-atom model shows that different statistical processes will influence the ionic diffusion coefficient in the WDM regime.

Wind tunnel test of a tailless aircraft with a belly-flap control surface used in combination with wing flaps

NASA Astrophysics Data System (ADS)

Dougherty, Daniel A.

A wind tunnel tat of a tailless aircraft configuration that has been quipped with a belly-flap control surface, was conducted with the goal of improving the trimmed maximum-lift coefficient. Tailless aircraft have aerodynamic and structural efficiencies that are superior to those of a traditionally configured wing/body/tail aircraft. However, tailless aircraft have a low maximum-lift coefficient such that; when sized for equivalent takeoff performance, the tailless aircraft suffers a large reduction in aerodynamic and structural efficiencies. A Belly-Flap control surface used in combination with wing trailing edge flaps was tested in a wind tunnel with the goal of achieving a longitudinally trimmed solution at a higher maximum lift coefficient. It was determined that, though the Belly-Flap increases the trimmed lift of the tailless configuration at low angles of attack, the maximum lift coefficient is slightly reduced in relation to the controls neutral configuration.

Microscale diffusion measurements and simulation of a scaffold with a permeable strut.

PubMed

Lee, Seung Youl; Lee, Byung Ryong; Lee, Jongwan; Kim, Seongjun; Kim, Jung Kyung; Jeong, Young Hun; Jin, Songwan

2013-10-10

Electrospun nanofibrous structures provide good performance to scaffolds in tissue engineering. We measured the local diffusion coefficients of 3-kDa FITC-dextran in line patterns of electrospun nanofibrous structures fabricated by the direct-write electrospinning (DWES) technique using the fluorescence recovery after photobleaching (FRAP) method. No significant differences were detected between DWES line patterns fabricated with polymer supplied at flow rates of 0.1 and 0.5 mL/h. The oxygen diffusion coefficients of samples were estimated to be ~92%-94% of the oxygen diffusion coefficient in water based on the measured diffusion coefficient of 3-kDa FITC-dextran. We also simulated cell growth and distribution within spatially patterned scaffolds with struts consisting of either oxygen-permeable or non-permeable material. The permeable strut scaffolds exhibited enhanced cell growth. Saturated depths at which cells could grow to confluence were 15% deeper for the permeable strut scaffolds than for the non-permeable strut scaffold.

Power industry competition, reengineering, and globalization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hyman, L.S.

1994-07-01

This article presents the views of a vice-president of a financial company on the future of the US electric utility industry. The topics of the article include a historical perspective of the structure of the industry, government regulation, deregulation and competition, rate structures and pricing, effects on stockholders and bondholders, and strategies for growth.

Bond lifetime and diffusion coefficient in colloids with short-range interactions.

PubMed

Ndong Mintsa, E; Germain, Ph; Amokrane, S

2015-03-01

We use molecular dynamics simulations to study the influence of short-range structures in the interaction potential between hard-sphere-like colloidal particles. Starting from model potentials and effective potentials in binary mixtures computed from the Ornstein-Zernike equations, we investigate the influence of the range and strength of a possible tail beyond the usual core repulsion or the presence of repulsive barriers. The diffusion coefficient and mean "bond" lifetimes are used as indicators of the effect of this structure on the dynamics. The existence of correlations between the variations of these quantities with the physical parameters is discussed to assess the interpretation of dynamics slowing down in terms of long-lived bonds. We also discuss the question of a universal behaviour determined by the second virial coefficient B ((2)) and the interplay of attraction and repulsion. While the diffusion coefficient follows the B ((2)) law for purely attractive tails, this is no longer true in the presence of repulsive barriers. Furthermore, the bond lifetime shows a dependence on the physical parameters that differs from that of the diffusion coefficient. This raises the question of the precise role of bonds on the dynamics slowing down in colloidal gels.

Analysis of heat conduction in a drum brake system of the wheeled armored personnel carriers

NASA Astrophysics Data System (ADS)

Puncioiu, A. M.; Truta, M.; Vedinas, I.; Marinescu, M.; Vinturis, V.

2015-11-01

This paper is an integrated study performed over the Braking System of the Wheeled Armored Personnel Carriers. It mainly aims to analyze the heat transfer process which is present in almost any industrial and natural process. The vehicle drum brake systems can generate extremely high temperatures under high but short duration braking loads or under relatively light but continuous braking. For the proper conduct of the special vehicles mission in rough terrain, we are talking about, on one hand, the importance of the possibility of immobilization and retaining position and, on the other hand, during the braking process, the importance movement stability and reversibility or reversibility, to an encounter with an obstacle. Heat transfer processes influence the performance of the braking system. In the braking phase, kinetic energy transforms into thermal energy resulting in intense heating and high temperature states of analyzed vehicle wheels. In the present work a finite element model for the temperature distribution in a brake drum is developed, by employing commercial finite element software, ANSYS. These structural and thermal FEA models will simulate entire braking event. The heat generated during braking causes distortion which modifies thermoelastic contact pressure distribution drum-shoe interface. In order to capture the effect of heat, a transient thermal analysis is performed in order to predict the temperature distribution transitional brake components. Drum brakes are checked both mechanical and thermal. These tests aim to establish their sustainability in terms of wear and the variation coefficient of friction between the friction surfaces with increasing temperature. Modeling using simulation programs led eventually to the establishment of actual thermal load of the mechanism of brake components. It was drawn the efficiency characteristic by plotting the coefficient of effectiveness relative to the coefficient of friction shoe-drum. Thus induced thermal loads determine thermo mechanical behavior of the structure of wheels. Study the transfer of heat generated during braking is useful because results can improve and validate existing theory or may lead to the development of a mathematical model to simulate the behavior of the brake system for various tactical and operational situations. Conclusions of this paper are relevant because theoretical data analysis results are validated by experimental research.

The impact of payer-specific hospital case mix on hospital costs and revenues for third-party patients.

PubMed

Lee, Keon-Hyung; Roh, M P H Chul-Young

2007-02-01

Competition among hospitals and managed care have forced hospital industry to be more efficient. With higher degrees of hospital competition and managed care penetration, hospitals have argued that the rate of increase in hospital cost is greater than the rate of increase in hospital revenue. By developing a payer-specific case mix index (CMI) for third-party patients, this paper examined the effect of hospital case mix on hospital cost and revenue for third-party patients in California using the hospital financial and utilization data covering 1986-1998. This study found that the coefficients for CMIs in the third-party hospital revenue model were greater than those in the hospital cost model until 1995. Since 1995, however, the coefficients for CMIs in the third-party hospital revenue model have been less than those in hospital cost models. Over time, the differences in coefficients for CMIs in hospital revenue and cost models for third-party patients have become smaller and smaller although those differences are statistically insignificant.

Methods for and estimates of 2003 and projected water use in the Seacoast Region, Southeastern New Hampshire

USGS Publications Warehouse

Horn, Marilee A.; Moore, Richard B.; Hayes, Laura; Flanagan, Sarah M.

2008-01-01

New methods were developed to estimate water use in 2003 and future water demand in 2017 and 2025 in the Seacoast region in southeastern New Hampshire, which has experienced a 37-percent population increase during 1980 to 2000. Water-use activities for which estimates were developed include water withdrawal, delivery, demand, consumptive use, release, return flow, and transfer by registered and aggregated unregistered (less than 20,000 gallons per day (gal/d)) users at the census-block and town scales. Estimates of water use rely on understanding what influences water demand and its associated consumptive use, because changes in demand and consumptive use affect withdrawal and return flow. Domestic water demand was estimated using a per capita water demand model that related metered deliveries to domestic users with census block and block-group data. The model was used to predict annual, summer, and winter per capita water-demand coefficients for each census block. Significant predictors of domestic water demand include population per housing unit, median value of owner-occupied single family homes, median year of housing construction (with 1900 as the base value), population density, housing unit density, and proportion of housing units that are in urban areas. Mean annual domestic per capita water-demand coefficient in the Seacoast region was 75 gal/d; the coefficient increased to 91 gal/d during the summer and decreased to 65 gal/d during the winter. Domestic consumptive use was estimated as the difference between annual and winter domestic water demand. Estimates of commercial and industrial water demand were based on coefficients derived from reported use and metered deliveries. Projections of water demand in 2017 and 2025 were determined by using the housing and employee projections for those years developed through a Transportation Demand Model and applying current domestic and non-domestic coefficients. Water demand in 2003 was estimated as 25.8 million gallons per day (Mgal/d), 35 percent of which was during the summer months of June, July, and August. Domestic water demand was 18.6 Mgal/d (72 percent), commercial water demand was 3.7 Mgal/d (14 percent), industrial water demand was 2.9 Mgal/d (11 percent), irrigation water demand was 0.3 Mgal/d (1 percent), and mining and aquaculture water demand was 0.2 Mgal/d (1 percent). Domestic consumptive use for the Seacoast region was 16 percent of domestic water demand, which translates to a loss of 3 Mgal/d over the entire Seacoast region. In 2003, water withdrawal was 771.2 Mgal/d, of which 742.2 Mgal/d was instream use for hydroelectric power generation and thermoelectric power cooling. The remaining 29.0 Mgal/d was withdrawn by community water systems (22.6 Mgal/d; 72 percent), domestic users (6.4 Mgal/d; 21 percent), commercial users (1.0 Mgal/d; 3 percent), industrial users (1.0 Mgal/d; 3 percent), irrigation (0.2 Mgal/d; 1 percent) and other users (less than 0.1 Mgal/d). Return flow for 2003 was 772.2 Mgal/d, of which 742.0 Mgal/d was returned following use for hydroelectric power generation and thermoelectric plant cooling. The remaining 30.2 Mgal/d was returned by community wastewater systems (20.2 Mgal/d; 68 percent), domestic users (7.8 Mgal/d; 26 percent), commercial users (1.2 Mgal/d; 3 percent), industrial users (0.8 Mgal/d; 3 percent), and other users (0.1 Mgal/d). Domestic water demand is projected to increase by 54 percent to 28.7 Mgal/d from 2003 to 2025 based on projection of future population growth. Non-domestic (commercial, industrial, irrigation, and mining) water demand is projected to increase by 66 percent to 11.8 Mgal/d from 2003 to 2025.

On the design of wave digital filters with low sensitivity properties.

NASA Technical Reports Server (NTRS)

Renner, K.; Gupta, S. C.

1973-01-01

The wave digital filter patterned after doubly terminated maximum available power (MAP) networks by means of the Richard's transformation has been shown to have low-coefficient-sensitivity properties. This paper examines the exact nature of the relationship between the wave-digital-filter structure and the MAP networks and how the sensitivity property arises, which permits implementation of the digital structure with a lower coefficient word length than that possible with the conventional structures. The proper design procedure is specified and the nature of the unique complementary outputs is discussed. Finally, an example is considered which illustrates the design, the conversion techniques, and the low sensitivity properties.

Mechanical design and analysis of a low beta squeezed half-wave resonator

NASA Astrophysics Data System (ADS)

He, Shou-Bo; Zhang, Cong; Yue, Wei-Ming; Wang, Ruo-Xu; Xu, Meng-Xin; Wang, Zhi-Jun; Huang, Shi-Chun; Huang, Yu-Lu; Jiang, Tian-Cai; Wang, Feng-Feng; Zhang, Sheng-Xue; He, Yuan; Zhang, Sheng-Hu; Zhao, Hong-Wei

2014-08-01

A superconducting squeezed type half-wave resonator (HWR) of β=0.09 has been developed at the Institute of Modern Physics, Lanzhou. In this paper, a basic design is presented for the stiffening structure for the detuning effect caused by helium pressure and Lorentz force. The mechanical modal analysis has been investigated the with finite element method (FEM). Based on these considerations, a new stiffening structure is proposed for the HWR cavity. The computation results concerning the frequency shift show that the low beta HWR cavity with new stiffening structure has low frequency sensitivity coefficient df/dp and Lorentz force detuning coefficient KL, and stable mechanical properties.

Factor Structure and Psychometric Properties of the Brief Illness Perception Questionnaire in Turkish Cancer Patients

PubMed Central

Karataş, Tuğba; Özen, Şükrü; Kutlutürkan, Sevinç

2017-01-01

Objective: The main aim of this study was to investigate the factor structure and psychometric properties of the Brief Illness Perception Questionnaire (BIPQ) in Turkish cancer patients. Methods: This methodological study involved 135 cancer patients. Statistical methods included confirmatory or exploratory factor analysis and Cronbach alpha coefficients for internal consistency. Results: The values of fit indices are within the acceptable range. The alpha coefficients for emotional illness representations, cognitive illness representations, and total scale are 0.83, 0.80, and 0.85, respectively. Conclusions: The results confirm the two-factor structure of the Turkish BIPQ and demonstrate its reliability and validity. PMID:28217734

Retrospective and Prospective Decomposition Analysis of Chinese Manufacturing Energy Use, 1995-2020

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hasanbeigi, Ali; Price, Lynn; Fino-Chen, Cecilia

In 2010, China was responsible for nearly 20 percent of global energy use and 25 percent of energy-related carbon dioxide (CO 2) emissions. Unlike most countries, China’s energy consumption pattern is unique because the industrial sector dominates the country’s total energy consumption, accounting for about 70 percent of energy use and 72 percent of CO 2 emissions in 2010. For this reason, the development path of China’s industrial sector will greatly affect future energy demand and dynamics of not only China, but the entire world. A number of analyses of historical trends have been conducted, but careful projections of themore » key factors affecting China’s industry sector energy use over the next decade are scarce. This study analyzes industrial energy use and the economic structure of the Chinese manufacturing sector in detail. First, the study analyzes the energy use of and output from 18 industry sub-sectors. Then, retrospective (1995-2010) and prospective (2010-2020) decomposition analyses are conducted for these industrial sectors in order to show how different factors (production growth, structural change, and energy intensity change) influenced industrial energy use trends in China over the last 15 years and how they will do so over the next 10 years. The results of this study will allow policy makers to quantitatively compare the level of structural change in the past and in the years to come and adjust their policies if needed to move towards the target of less energy-intensive industries. The scenario analysis shows the structural change achieved through different paths and helps to understand the consequences of supporting or limiting the growth of certain manufacturing subsectors from the point of view of energy use and structural change. The results point out the industries that have the largest influence in such structural change« less

Determination of the transmission coefficients for quantum structures using FDTD method.

PubMed

Peng, Yangyang; Wang, Xiaoying; Sui, Wenquan

2011-12-01

The purpose of this work is to develop a simple method to incorporate quantum effect in traditional finite-difference time-domain (FDTD) simulators. Witch could make it possible to co-simulate systems include quantum structures and traditional components. In this paper, tunneling transmission coefficient is calculated by solving time-domain Schrödinger equation with a developed FDTD technique, called FDTD-S method. To validate the feasibility of the method, a simple resonant tunneling diode (RTD) structure model has been simulated using the proposed method. The good agreement between the numerical and analytical results proves its accuracy. The effectness and accuracy of this approach makes it a potential method for analysis and design of hybrid systems includes quantum structures and traditional components.

Quantifying Errors in Jet Noise Research Due to Microphone Support Reflection

NASA Technical Reports Server (NTRS)

Nallasamy, Nambi; Bridges, James

2002-01-01

The reflection coefficient of a microphone support structure used insist noise testing is documented through tests performed in the anechoic AeroAcoustic Propulsion Laboratory. The tests involve the acquisition of acoustic data from a microphone mounted in the support structure while noise is generated from a known broadband source. The ratio of reflected signal amplitude to the original signal amplitude is determined by performing an auto-correlation function on the data. The documentation of the reflection coefficients is one component of the validation of jet noise data acquired using the given microphone support structure. Finally. two forms of acoustic material were applied to the microphone support structure to determine their effectiveness in reducing reflections which give rise to bias errors in the microphone measurements.

A displacement-based approach for determining non-linear effects on pre-tensioned-cable cross-braced structures

NASA Astrophysics Data System (ADS)

Giaccu, Gian Felice; Caracoglia, Luca

2017-04-01

Pre-tensioned-cable bracing systems are widely employed in structural engineering to limit lateral deflections and stabilize structures. A suitable configuration of the pre-tensioned-cable bracing systems in a structure is an important issue since the internal force distribution, emerging from the interaction with the existing structure, significantly affects the structural dynamic behavior. The design, however, is often based on the intuition and the previous experience of the engineer. In recent years, the authors have been investigating the non-linear dynamic response of cable systems, installed on cable-stayed bridges, and in particular the so-called "cable-cross-tie systems" forming a cable network. The bracing cables (cross-ties) can exhibit slackening or snapping. Therefore, a non-linear unilateral model, combined with the taut-cable theory, is required to simulate the incipient slackening conditions in the stays. Capitalizing from this work on non-linear cable dynamics, this paper proposes a new approach to analyze, in laterally- braced truss structures, the unilateral effects and dynamic response accounting for the loss in the pre-tensioning force imparted to the bracing cables. This effect leads to non-linear vibration of the structure. In this preliminary study, the free vibrations of the structure are investigated by using the "Equivalent Linearization Method". A performance coefficient, a real positive number between 0.5 and 1.0, is defined and employed to monitor the relative reduction in the apparent stiffness of the braces during structural vibration, "mode by mode". It is shown that the system can exhibit alternate unilateral behavior of the cross-braces. A reduction of the performance coefficient close to fifty percent is observed in the braces when the initial pre-tensioning force is small. On the other hand the performance coefficient tends to one in the case of a high level of pre-stress. It is concluded that the performance coefficient may possibly be used as an indicator for the design of the braces since a suitable selection of the initial pre-tensioning force can avoid slackening in the braces.

[Decomposition model of energy-related carbon emissions in tertiary industry for China].

PubMed

Lu, Yuan-Qing; Shi, Jun

2012-07-01

Tertiary industry has been developed in recent years. And it is very important to find the factors influenced the energy-related carbon emissions in tertiary industry. A decomposition model of energy-related carbon emissions for China is set up by adopting logarithmic mean weight Divisia method based on the identity of carbon emissions. The model is adopted to analyze the influence of energy structure, energy efficiency, tertiary industry structure and economic output to energy-related carbon emissions in China from 2000 to 2009. Results show that the contribution rate of economic output and energy structure to energy-related carbon emissions increases year by year. Either is the contribution rate of energy efficiency or the tertiary industry restraining to energy-related carbon emissions. However, the restrain effect is weakening.

Estimating Seven Coefficients of Pairwise Relatedness Using Population-Genomic Data

PubMed Central

Ackerman, Matthew S.; Johri, Parul; Spitze, Ken; Xu, Sen; Doak, Thomas G.; Young, Kimberly; Lynch, Michael

2017-01-01

Population structure can be described by genotypic-correlation coefficients between groups of individuals, the most basic of which are the pairwise relatedness coefficients between any two individuals. There are nine pairwise relatedness coefficients in the most general model, and we show that these can be reduced to seven coefficients for biallelic loci. Although all nine coefficients can be estimated from pedigrees, six coefficients have been beyond empirical reach. We provide a numerical optimization procedure that estimates all seven reduced coefficients from population-genomic data. Simulations show that the procedure is nearly unbiased, even at 3× coverage, and errors in five of the seven coefficients are statistically uncorrelated. The remaining two coefficients have a negative correlation of errors, but their sum provides an unbiased assessment of the overall correlation of heterozygosity between two individuals. Application of these new methods to four populations of the freshwater crustacean Daphnia pulex reveal the occurrence of half siblings in our samples, as well as a number of identical individuals that are likely obligately asexual clone mates. Statistically significant negative estimates of these pairwise relatedness coefficients, including inbreeding coefficients that were typically negative, underscore the difficulties that arise when interpreting genotypic correlations as estimations of the probability that alleles are identical by descent. PMID:28341647

Determinants of Iran's BilateralIntra-industry Trade in Pharmaceutical Industry.

PubMed

Aghlmand, Siamak; Rahimi, Bahlol; Farrokh-Eslamlou, Hamidreza; Nabilou, Bahram; Yusefzadeh, Hassan

2018-01-01

Among non-oil and in trade arena, drug has always been strategic importance and most government especially industrialized countries pay special attention to its production and trade issues. Thus, having a comprehensive view from economic perspective to this section is essential for suggesting intervention. This was a descriptive-analytical and panel study. In this study, gravity model is used to estimate Iran's bilateral intra-industry trade in pharmaceutical products in the 2001-2012 periods. To illustrate the extent of pharmaceutical's intra-industry trade between Iran and its major trading partners, the explanatory variables of market size, income, factor endowments, distance, cultural contributions, and similarities and also special trade arrangements have been applied. Analysis of factors affecting Iran's bilateral intra-industry trade in pharmaceutical industry showed that the average GDP and cultural similarities had a significant positive impact on Iran's bilateral IIT, while the difference in GDP has a negative and significant effect. Coefficients obtained for the geographical distance and the average ratio of total capital to the labor force is not consistent with theoretical expectations. Special trade arrangements did not have significant impact on the extent of bilateral intra-industry trade between Iran and its trading partners. The knowledge of the intra-industry trade between Iran and its trade partners make integration between the countries. Factors affecting this type of trade pattern underlie its development in trade relationship. Therefore, the findings of this study would be useful in helping to develop and implement policies for the expansion of the pharmaceutical trade.

The use of computational thermodynamics for the determination of surface tension and Gibbs-Thomson coefficient of multicomponent alloys

NASA Astrophysics Data System (ADS)

Ferreira, D. J. S.; Bezerra, B. N.; Collyer, M. N.; Garcia, A.; Ferreira, I. L.

2018-04-01

The simulation of casting processes demands accurate information on the thermophysical properties of the alloy; however, such information is scarce in the literature for multicomponent alloys. Generally, metallic alloys applied in industry have more than three solute components. In the present study, a general solution of Butler's formulation for surface tension is presented for multicomponent alloys and is applied in quaternary Al-Cu-Si-Fe alloys, thus permitting the Gibbs-Thomson coefficient to be determined. Such coefficient is a determining factor to the reliability of predictions furnished by microstructure growth models and by numerical computations of solidification thermal parameters, which will depend on the thermophysical properties assumed in the calculations. The Gibbs-Thomson coefficient for ternary and quaternary alloys is seldom reported in the literature. A numerical model based on Powell's hybrid algorithm and a finite difference Jacobian approximation has been coupled to a Thermo-Calc TCAPI interface to assess the excess Gibbs energy of the liquid phase, permitting liquidus temperature, latent heat, alloy density, surface tension and Gibbs-Thomson coefficient for Al-Cu-Si-Fe hypoeutectic alloys to be calculated, as an example of calculation capabilities for multicomponent alloys of the proposed method. The computed results are compared with thermophysical properties of binary Al-Cu and ternary Al-Cu-Si alloys found in the literature and presented as a function of the Cu solute composition.

The Factor Structure of the Spiritual Well-Being Scale in Veterans Experienced Chemical Weapon Exposure.

PubMed

Sharif Nia, Hamid; Pahlevan Sharif, Saeed; Boyle, Christopher; Yaghoobzadeh, Ameneh; Tahmasbi, Bahram; Rassool, G Hussein; Taebei, Mozhgan; Soleimani, Mohammad Ali

2018-04-01

This study aimed to determine the factor structure of the spiritual well-being among a sample of the Iranian veterans. In this methodological research, 211 male veterans of Iran-Iraq warfare completed the Paloutzian and Ellison spiritual well-being scale. Maximum likelihood (ML) with oblique rotation was used to assess domain structure of the spiritual well-being. The construct validity of the scale was assessed using confirmatory factor analysis (CFA), convergent validity, and discriminant validity. Reliability was evaluated with Cronbach's alpha, Theta (θ), and McDonald Omega (Ω) coefficients, intra-class correlation coefficient (ICC), and construct reliability (CR). Results of ML and CFA suggested three factors which were labeled "relationship with God," "belief in fate and destiny," and "life optimism." The ICC, coefficients of the internal consistency, and CR were >.7 for the factors of the scale. Convergent validity and discriminant validity did not fulfill the requirements. The Persian version of spiritual well-being scale demonstrated suitable validity and reliability among the veterans of Iran-Iraq warfare.

Effects of the interface roughness in metal-adhesive-metal structure on the propagation of shear horizontal waves.

PubMed

Ech Cherif El Kettani, Mounsif; Leduc, Damien; Potel, Catherine; Bruneau, Michel; Foze, Ludovic; Predoi, Mihai

2017-06-01

The influence of the interface roughness in a three-layer metal-adhesive-metal structure on the propagation of shear horizontal waves and more particularly on the transmission coefficient versus the frequency is studied in the particular case of a periodic grating of triangular grooves. For given phonon frequencies, the interaction of an incident shear horizontal mode with the periodical grating gives rise to a retro-converted mode. A numerical finite element simulation permits us to predict the existence of the phonon mode in the three-layer structure and to obtain the evolution of the transmission coefficient around the phonon frequency. An experimental study, based on a generation of waves by a piezocomposite contact transducer and a reception by a laser vibrometer, then confirms these predictions. Finally, a parametric numerical study is performed: the influence of the depth of the roughness and of the number of spatial periods of the grooves on the transmission coefficient is studied.

On the modular structure of the genus-one Type II superstring low energy expansion

NASA Astrophysics Data System (ADS)

D'Hoker, Eric; Green, Michael B.; Vanhove, Pierre

2015-08-01

The analytic contribution to the low energy expansion of Type II string amplitudes at genus-one is a power series in space-time derivatives with coefficients that are determined by integrals of modular functions over the complex structure modulus of the world-sheet torus. These modular functions are associated with world-sheet vacuum Feynman diagrams and given by multiple sums over the discrete momenta on the torus. In this paper we exhibit exact differential and algebraic relations for a certain infinite class of such modular functions by showing that they satisfy Laplace eigenvalue equations with inhomogeneous terms that are polynomial in non-holomorphic Eisenstein series. Furthermore, we argue that the set of modular functions that contribute to the coefficients of interactions up to order are linear sums of functions in this class and quadratic polynomials in Eisenstein series and odd Riemann zeta values. Integration over the complex structure results in coefficients of the low energy expansion that are rational numbers multiplying monomials in odd Riemann zeta values.

Application of an Unstructured Grid Navier-Stokes Solver to a Generic Helicopter Boby: Comparison of Unstructured Grid Results with Structured Grid Results and Experimental Results

NASA Technical Reports Server (NTRS)

Mineck, Raymond E.

1999-01-01

An unstructured-grid Navier-Stokes solver was used to predict the surface pressure distribution, the off-body flow field, the surface flow pattern, and integrated lift and drag coefficients on the ROBIN configuration (a generic helicopter) without a rotor at four angles of attack. The results are compared to those predicted by two structured- grid Navier-Stokes solvers and to experimental surface pressure distributions. The surface pressure distributions from the unstructured-grid Navier-Stokes solver are in good agreement with the results from the structured-grid Navier-Stokes solvers. Agreement with the experimental pressure coefficients is good over the forward portion of the body. However, agreement is poor on the lower portion of the mid-section of the body. Comparison of the predicted surface flow patterns showed similar regions of separated flow. Predicted lift and drag coefficients were in fair agreement with each other.

[Quantitative structure-gas chromatographic retention relationship of polycyclic aromatic sulfur heterocycles using molecular electronegativity-distance vector].

PubMed

Li, Zhenghua; Cheng, Fansheng; Xia, Zhining

2011-01-01

The chemical structures of 114 polycyclic aromatic sulfur heterocycles (PASHs) have been studied by molecular electronegativity-distance vector (MEDV). The linear relationships between gas chromatographic retention index and the MEDV have been established by a multiple linear regression (MLR) model. The results of variable selection by stepwise multiple regression (SMR) and the powerful predictive abilities of the optimization model appraised by leave-one-out cross-validation showed that the optimization model with the correlation coefficient (R) of 0.994 7 and the cross-validated correlation coefficient (Rcv) of 0.994 0 possessed the best statistical quality. Furthermore, when the 114 PASHs compounds were divided into calibration and test sets in the ratio of 2:1, the statistical analysis showed our models possesses almost equal statistical quality, the very similar regression coefficients and the good robustness. The quantitative structure-retention relationship (QSRR) model established may provide a convenient and powerful method for predicting the gas chromatographic retention of PASHs.

Decoupling the electrical conductivity and Seebeck coefficient in the RE2SbO2 compounds through local structural perturbations.

PubMed

Wang, Peng L; Kolodiazhnyi, Taras; Yao, Jinlei; Mozharivskyj, Yurij

2012-01-25

Compromise between the electrical conductivity and Seebeck coefficient limits the efficiency of chemical doping in the thermoelectric research. An alternative strategy, involving the control of a local crystal structure, is demonstrated to improve the thermoelectric performance in the RE(2)SbO(2) system. The RE(2)SbO(2) phases, adopting a disordered anti-ThCr(2)Si(2)-type structure (I4/mmm), were prepared for RE = La, Nd, Sm, Gd, Ho, and Er. By traversing the rare earth series, the lattice parameters of the RE(2)SbO(2) phases are gradually reduced, thus increasing chemical pressure on the Sb environment. As the Sb displacements are perturbed, different charge carrier activation mechanisms dominate the transport properties of these compounds. As a result, the electrical conductivity and Seebeck coefficient are improved simultaneously, while the number of charge carriers in the series remains constant. © 2012 American Chemical Society

A spline-based parameter estimation technique for static models of elastic structures

NASA Technical Reports Server (NTRS)

Dutt, P.; Taasan, S.

1986-01-01

The problem of identifying the spatially varying coefficient of elasticity using an observed solution to the forward problem is considered. Under appropriate conditions this problem can be treated as a first order hyperbolic equation in the unknown coefficient. Some continuous dependence results are developed for this problem and a spline-based technique is proposed for approximating the unknown coefficient, based on these results. The convergence of the numerical scheme is established and error estimates obtained.

Black holes, information, and the universal coefficient theorem

DOE Office of Scientific and Technical Information (OSTI.GOV)

Patrascu, Andrei T.

2016-07-15

General relativity is based on the diffeomorphism covariant formulation of the laws of physics while quantum mechanics is based on the principle of unitary evolution. In this article, I provide a possible answer to the black hole information paradox by means of homological algebra and pairings generated by the universal coefficient theorem. The unitarity of processes involving black holes is restored by the demanding invariance of the laws of physics to the change of coefficient structures in cohomology.

A Mössbauer spectroscopic study of an industrial catalyst for dehydrogenation of etylbenzene to styrene

NASA Astrophysics Data System (ADS)

Jiang, K. Y.; Fan, Q.; Zhao, Z. J.; Mao, L. S.; Yang, X. L.

2006-01-01

Iron oxide catalyst with spinel structure used for dehydrogenation of ethylbenzene is one kind of important catalyst in petrochemical industry. In this work several series of industrial catalyst were prepared with different components and different manufacturing processes. Mössbauer Spectroscopy has been used to determine the optimal components and the better manufacturing process for spinel structure formation. The results may prove useful for producing the industrial dehydrogenation catalyst with better catalytic property.

A Mössbauer spectroscopic study of an industrial catalyst for dehydrogenation of etylbenzene to styrene

NASA Astrophysics Data System (ADS)

Jiang, K. Y.; Fan, Q.; Zhao, Z. J.; Mao, L. S.; Yang, X. L.

Iron oxide catalyst with spinel structure used for dehydrogenation of ethylbenzene is one kind of importantcatalyst in petrochemical industry. In this work several series of industrial catalyst were prepared with differentcomponents and differentmanufacturing processes. Mössbauer Spectroscopy has been used to determine the optimal components and the better manufacturing process for spinel structure formation. The results may prove useful for producing the industrial dehydrogenation catalyst with better catalytic property.

PZT/PLZT - elastomer composites with improved piezoelectric voltage coefficient

NASA Astrophysics Data System (ADS)

Harikrishnan, K.; Bavbande, D. V.; Mohan, Dhirendra; Manoharan, B.; Prasad, M. R. S.; Kalyanakrishnan, G.

2018-02-01

Lead Zirconate Titanate (PZT) and Lanthanum-modified Lead Zirconate Titanate (PLZT) ceramic sensor materials are widely used because of their excellent piezoelectric coefficients. These materials are brittle, high density and have low achievable piezoelectric voltage coefficients. The density of the sintered ceramics shall be reduced by burnable polymeric sponge method. The achievable porosity level in this case is nearly 60 - 90%. However, the porous ceramic structure with 3-3 connectivity produced by this method is very fragile in nature. The strength of the porous structure is improved with Sylgard®-184 (silicone elastomer) by vacuum impregnation method maintaining the dynamic vacuum level in the range of -650 mm Hg. The elastomer Sylgard®-184 is having low density, low dielectric constant and high compliance (as a resultant stiffness of the composites is increased). To obtain a net dipole moment, the impregnated ceramic composites were subjected to poling treatment with varying conditions of D.C. field and temperature. The properties of the poled PZT/PLZT - elastomer composites were characterized with LCR meter for measuring the dielectric constant values (k), d33 meter used for measuring piezo-electric charge coefficient values (d33) and piezo-electric voltage coefficient (g33) values which were derived from d33 values. The voltage coefficient (g33) values of these composites are increased by 10 fold as compared to the conventional solid ceramics demonstrates that it is possible to fabricate a conformable detector.

The Electronic Structure and Secondary Pyroelectric Properties of Lithium Tetraborate

PubMed Central

Adamiv, Volodymyr.T.; Burak, Yaroslav.V.; Wooten, David. J.; McClory, John; Petrosky, James; Ketsman, Ihor; Xiao, Jie; Losovyj, Yaroslav B.; Dowben, Peter A.

2010-01-01

We review the pyroelectric properties and electronic structure of Li2B4O7(110) and Li2B4O7(100) surfaces. There is evidence for a pyroelectric current along the [110] direction of stoichiometric Li2B4O7 so that the pyroelectric coefficient is nonzero but roughly 103 smaller than along the [001] direction of spontaneous polarization. Abrupt decreases in the pyroelectric coefficient along the [110] direction can be correlated with anomalies in the elastic stiffness C33D contributing to the concept that the pyroelectric coefficient is not simply a vector but has qualities of a tensor, as expected. The time dependent surface photovoltaic charging suggests that surface charging is dependent on crystal orientation and doping, as well as temperature. PMID:28883341

[The appraisal of reliability and validity of subjective workload assessment technique and NASA-task load index].

PubMed

Xiao, Yuan-mei; Wang, Zhi-ming; Wang, Mian-zhen; Lan, Ya-jia

2005-06-01

To test the reliability and validity of two mental workload assessment scales, i.e. subjective workload assessment technique (SWAT) and NASA task load index (NASA-TLX). One thousand two hundred and sixty-eight mental workers were sampled from various kinds of occupations, such as scientific research, education, administration and medicine, etc, with randomized cluster sampling. The re-test reliability, split-half reliability, Cronbach's alpha coefficient and correlation coefficients between item score and total score were adopted to test the reliability. The test of validity included structure validity. The re-test reliability coefficients of these two scales and their items were ranged from 0.516 to 0.753 (P < 0.01), indicating the two scales had good re-test reliability; the split-half reliability of SWAT was 0.645, and its Cronbach's alpha coefficient was more than 0.80, all the correlation coefficients between its items score and total score were more than 0.70; as for NASA-TLX, both the split-half reliability and Cronbach's alpha coefficient were more than 0.80, the correlation coefficients between its items score and total score were all more than 0.60 (P < 0.01) except the item of performance. Both scales had good inner consistency. The Pearson correlation coefficient between the two scales was 0.492 (P < 0.01), implying the results of the two scales had good consistency. Factor analysis showed that the two scales had good structure validity. Both SWAT and NASA-TLX have good reliability and validity and may be used as a valid tool to assess mental workload in China after being revised properly.

Implications of next generation attenuation ground motion prediction equations for site coefficients used in earthquake resistant design

USGS Publications Warehouse

Borcherdt, Roger D.

2014-01-01

Proposals are developed to update Tables 11.4-1 and 11.4-2 of Minimum Design Loads for Buildings and Other Structures published as American Society of Civil Engineers Structural Engineering Institute standard 7-10 (ASCE/SEI 7–10). The updates are mean next generation attenuation (NGA) site coefficients inferred directly from the four NGA ground motion prediction equations used to derive the maximum considered earthquake response maps adopted in ASCE/SEI 7–10. Proposals include the recommendation to use straight-line interpolation to infer site coefficients at intermediate values of (average shear velocity to 30-m depth). The NGA coefficients are shown to agree well with adopted site coefficients at low levels of input motion (0.1 g) and those observed from the Loma Prieta earthquake. For higher levels of input motion, the majority of the adopted values are within the 95% epistemic-uncertainty limits implied by the NGA estimates with the exceptions being the mid-period site coefficient, Fv, for site class D and the short-period coefficient, Fa, for site class C, both of which are slightly less than the corresponding 95% limit. The NGA data base shows that the median value  of 913 m/s for site class B is more typical than 760 m/s as a value to characterize firm to hard rock sites as the uniform ground condition for future maximum considered earthquake response ground motion estimates. Future updates of NGA ground motion prediction equations can be incorporated easily into future adjustments of adopted site coefficients using procedures presented herein. 

Clinical and microperimetric predictors of reading speed in low vision patients: a structural equation modeling approach.

PubMed

Giacomelli, Giovanni; Virgili, Gianni; Giansanti, Fabrizio; Sato, Giovanni; Cappello, Ezio; Cruciani, Filippo; Varano, Monica; Menchini, Ugo

2013-06-27

To investigate the simultaneous association of several psychophysical measures with reading ability in patients with mild and moderate low vision attending rehabilitation services. Standard measurements of reading ability (Minnesota Reading [MNREAD] charts), visual acuity (Early Treatment of Diabetic Retinopathy Study [ETDRS] charts), contrast sensitivity (Pelli-Robson charts), reading contrast threshold (Reading Explorer [REX] charts), retinal sensitivity, and fixation stability and localization (Micro Perimeter 1 [MP1] fundus perimetry) were obtained in 160 low vision patients with better eye visual acuity ranging from 0.3 to 1.0 logarithm of the minimum angle of resolution and affected by either age-related macular degeneration or diabetic retinopathy. All variables were moderately associated with reading performance measures (MNREAD reading speed and reading acuity and REX reading contrast threshold), as well as among each other. In a structural equation model, REX reading contrast threshold was highly associated with MNREAD reading speed (standardized coefficient, 0.63) and moderately associated with reading acuity (standardized coefficient, -0.30). REX test also mediated the effects of Pelli-Robson contrast sensitivity (standardized coefficient, 0.44), MP1 fixation eccentricity (standardized coefficient, -0.19), and the mean retinal sensitivity (standardized coefficient, 0.23) on reading performance. The MP1 fixation stability was associated with both MNREAD reading acuity (standardized coefficient, -0.24) and MNREAD reading speed (standardized coefficient, 0.23), while ETDRS visual acuity only affected reading acuity (standardized coefficient, 0.44). Fixation instability and contrast sensitivity loss are key factors limiting reading performance of patients with mild or moderate low vision. REX charts directly assess the impact of text contrast on letter recognition and text navigation and may be a useful aid in reading rehabilitation.

The Urban Heat Island Impact in Consideration of Spatial Pattern of Urban Landscape and Structure

NASA Astrophysics Data System (ADS)

Kim, J.; Lee, D. K.; Jeong, W.; Sung, S.; Park, J.

2015-12-01

Preceding study has established a clear relationship between land surface temperature and area of land covers. However, only few studies have specifically examined the effects of spatial patterns of land covers and urban structure. To examine how much the local climate is affected by the spatial pattern in highly urbanized city, we investigated the correlation between land surface temperature and spatial patterns of land covers. In the analysis of correlation, we categorized urban structure to four different land uses: Apartment residential area, low rise residential area, industrial area and central business district. Through this study, we aims to examine the types of residential structure and land cover pattern for reducing urban heat island and sustainable development. Based on land surface temperature, we investigated the phenomenon of urban heat island through using the data of remote sensing. This study focused on Daegu in Korea. This city, one of the hottest city in Korea has basin form. We used high-resolution land cover data and land surface temperature by using Landsat8 satellite image to examine 100 randomly selected sample sites of 884.15km2 (1)In each land use, we quantified several landscape-levels and class-level landscape metrics for the sample study sites. (2)In addition, we measured the land surface temperature in 3 year hot summer seasons (July to September). Then, we investigated the pattern of land surface temperature for each land use through Ecognition package. (3)We deducted the Pearson correlation coefficients between land surface temperature and each landscape metrics. (4)We analyzed the variance among the four land uses. (5)Using linear regression, we determined land surface temperature model for each land use. (6)Through this analysis, we aims to examine the best pattern of land cover and artificial structure for reducing urban heat island effect in highly urbanized city. The results of linear regression showed that proportional land cover of grass, tree, water and impervious surfaces well explained the temperature in apartment residential areas. In contrast, the changes in the pattern of water, grass, tree and impervious surfaces were the best to determine the temperature in low rise residential area, central business district and industrial area.

Relativistic quasiparticle band structures of Mg2Si, Mg2Ge, and Mg2Sn: Consistent parameterization and prediction of Seebeck coefficients

NASA Astrophysics Data System (ADS)

Shi, Guangsha; Kioupakis, Emmanouil

2018-02-01

We apply density functional and many-body perturbation theory calculations to consistently determine and parameterize the relativistic quasiparticle band structures of Mg2Si, Mg2Ge, and Mg2Sn, and predict the Seebeck coefficient as a function of doping and temperature. The quasiparticle band gaps, including spin-orbit coupling effects, are determined to be 0.728 eV, 0.555 eV, and 0.142 eV for Mg2Si, Mg2Ge, and Mg2Sn, respectively. The inclusion of the semicore electrons of Mg, Ge, and Sn in the valence is found to be important for the accurate determination of the band gaps of Mg2Ge and Mg2Sn. We also developed a Luttinger-Kohn Hamiltonian and determined a set of band parameters to model the near-edge relativistic quasiparticle band structure consistently for all three compounds that can be applied for thermoelectric device simulations. Our calculated values for the Seebeck coefficient of all three compounds are in good agreement with the available experimental data for a broad range of temperatures and carrier concentrations. Our results indicate that quasiparticle corrections are necessary for the accurate determination of Seebeck coefficients at high temperatures at which bipolar transport becomes important.

Effect of mesoporous structure on the Seebeck coefficient and electrical properties of SrTi0.8Nb0.2O3

NASA Astrophysics Data System (ADS)

Park, Chang-Sun; Hong, Min-Hee; Cho, Hyung Hee; Park, Hyung-Ho

2017-07-01

The porosity of mesoporous SrTi0.8Nb0.2O3 (STNO) was controlled by changing the surfactant concentration to investigate the porosity effect on the thermoelectric properties. Mesoporous structure typically induces a large decrease in the carrier mobility and a small increase in the carrier concentration owing to carrier scattering and oxygen vacancies. These changes in the carrier mobility and concentration induce a change in the thermoelectric properties by enhancing the Seebeck coefficient owing to an increase in the electrical resistivity and carrier filtering effect. Brij-S10 surfactant induces a carrier filtering effect in STNO, and so the Seebeck coefficient could be enhanced even with increasing carrier concentration. Because the Seebeck coefficient affects the power factor more strongly than the electrical resistivity does, incorporation of Brij-S10 surfactant into STNO films increases the power factor. The maximum value of the power factor, approximately 2.2 × 10-4 W/mK2 at 200 °C, was obtained at a Brij-S10 molar ratio of 0.075. From this result, we can expect the application of STNO as a thermoelectric material with an enhanced power factor through successful adoption of mesoporous structure.

JPRS Report, China.

DTIC Science & Technology

1991-04-16

mice , color monitors, image Industrial Production Rises Over 6 Percent First 2 scanners, key-boards and drawing cards in 1990. Months The center...Adjusting Industrial Structure, Suggestions 32 Experts Forecast 1991 Market Trends [ZHONGGUO TONGJI XIAOXI BAO 11 Feb] ................. 35 Price Index of...Policies Regarding Industrial Structure in Hunan [HUNAN RIBAO 5 Feb] ........................... 45 Bank Official Views 1991 Monetary Policies [JINRONG

The Decline of Industrial Unionism in the Meatpacking Industry: Event-Structure Analyses of Labor Unrest, 1946-1987.

ERIC Educational Resources Information Center

Brueggemann, John; Brown, Cliff

2003-01-01

A study of the United Packinghouse Workers of America compared the postwar years and the Reagan era. Using event-structure analysis, the development of new corporate strategies (new technologies, production reorganization, cheap nonunion labor) fundamentally transformed the capital-labor relationship and led to the collapse of industrial unionism…

Recent Trends in the Structure of the Cable Television Industry.

ERIC Educational Resources Information Center

Perry, Martin

After a brief review of the growth of cable television from 1948 to 1965, the paper examines in more detail trends in the structure of the industry since 1965. Specifically, interest revolves around the apparent trends of concentration and vertical integration within the industry. Corporate histories of the leading firms are then used to…

Occupational and Qualification Structures in the Field of Environmental Protection in the Metal and Chemical Industries in Italy.

ERIC Educational Resources Information Center

Stanzani, Claudio

This report provides an initial analysis of the occupational and qualification structures in the field of environmental protection in the Italian metal and chemical industries. The first two chapters review the legislative background, situation in industry, and provision of environmental education and training. The third chapter presents results…

Iowa High School Industrial Arts Curriculum Project. Report on Year One of Phase II.

ERIC Educational Resources Information Center

Des Moines Public Schools, IA.

Phase II of the Iowa High School Industrial Arts project sought to revise industrial arts content to include the infusion of new technologies, structured mathematics and science content, and a less project-oriented approach to teaching. The project identified a philosophical basis and a content structure; set priorities for development and…

Structuring of manual of orientations and technical information for laundries of industries of animal products origin.

PubMed

da Silva, Vania Eugênia; Mafra, Simone Caldas Tavares; Mafra, Cláudio Lísias; de Souza, Amaury Paulo

2012-01-01

This study looked for to lift information regarding laundries inserted in industries of animal products origin, to understand the activities developed in the section and to structure a Manual of Planning and Technical Information for laundries to industries of animal products origin, with the intention of subsidizing the planning, structuring and control of this work place, because norms or regulations that supervise don't exist or aid their managers and workers as for the operation of this work place.

Multilevel Dynamic Generalized Structured Component Analysis for Brain Connectivity Analysis in Functional Neuroimaging Data.

PubMed

Jung, Kwanghee; Takane, Yoshio; Hwang, Heungsun; Woodward, Todd S

2016-06-01

We extend dynamic generalized structured component analysis (GSCA) to enhance its data-analytic capability in structural equation modeling of multi-subject time series data. Time series data of multiple subjects are typically hierarchically structured, where time points are nested within subjects who are in turn nested within a group. The proposed approach, named multilevel dynamic GSCA, accommodates the nested structure in time series data. Explicitly taking the nested structure into account, the proposed method allows investigating subject-wise variability of the loadings and path coefficients by looking at the variance estimates of the corresponding random effects, as well as fixed loadings between observed and latent variables and fixed path coefficients between latent variables. We demonstrate the effectiveness of the proposed approach by applying the method to the multi-subject functional neuroimaging data for brain connectivity analysis, where time series data-level measurements are nested within subjects.

The motivations, institutions and organization of university-industry collaborations in the Netherlands.

PubMed

Bodas Freitas, Isabel Maria; Verspagen, Bart

2017-01-01

This study builds on the economics and organization literatures to explore whether and how institutions and organizational structure complement or substitute each other to create specific spaces of alignment where specific individual actors' motivations co-exist. Focusing on university-industry collaborations, the study examines whether and how different axes of alignment of university and industry motivations are integrated in projects with specific technological objectives and organizational structures, benefitting from the presence of specific institutions designed to facilitate collaboration. Empirically, the study relies on in-depth data on 30 university-industry collaborations in the Netherlands, and provides preliminary evidence that the technological objective and organizational structure of collaboration are malleable variables allowing the integration of both partners' objectives and expectations. Different institutional incentives for university-industry collaboration favor specific axes of alignment of motivations and certain types of collaborative projects' design. Hence, our exploratory results suggest that specific organizational and technological structures tend to prevail in the presence of specific institutions.

The influence of phylogeny, social style, and sociodemographic factors on macaque social network structure.

PubMed

Balasubramaniam, Krishna N; Beisner, Brianne A; Berman, Carol M; De Marco, Arianna; Duboscq, Julie; Koirala, Sabina; Majolo, Bonaventura; MacIntosh, Andrew J; McFarland, Richard; Molesti, Sandra; Ogawa, Hideshi; Petit, Odile; Schino, Gabriele; Sosa, Sebastian; Sueur, Cédric; Thierry, Bernard; de Waal, Frans B M; McCowan, Brenda

2018-01-01

Among nonhuman primates, the evolutionary underpinnings of variation in social structure remain debated, with both ancestral relationships and adaptation to current conditions hypothesized to play determining roles. Here we assess whether interspecific variation in higher-order aspects of female macaque (genus: Macaca) dominance and grooming social structure show phylogenetic signals, that is, greater similarity among more closely-related species. We use a social network approach to describe higher-order characteristics of social structure, based on both direct interactions and secondary pathways that connect group members. We also ask whether network traits covary with each other, with species-typical social style grades, and/or with sociodemographic characteristics, specifically group size, sex-ratio, and current living condition (captive vs. free-living). We assembled 34-38 datasets of female-female dyadic aggression and allogrooming among captive and free-living macaques representing 10 species. We calculated dominance (transitivity, certainty), and grooming (centrality coefficient, Newman's modularity, clustering coefficient) network traits as aspects of social structure. Computations of K statistics and randomization tests on multiple phylogenies revealed moderate-strong phylogenetic signals in dominance traits, but moderate-weak signals in grooming traits. GLMMs showed that grooming traits did not covary with dominance traits and/or social style grade. Rather, modularity and clustering coefficient, but not centrality coefficient, were strongly predicted by group size and current living condition. Specifically, larger groups showed more modular networks with sparsely-connected clusters than smaller groups. Further, this effect was independent of variation in living condition, and/or sampling effort. In summary, our results reveal that female dominance networks were more phylogenetically conserved across macaque species than grooming networks, which were more labile to sociodemographic factors. Such findings narrow down the processes that influence interspecific variation in two core aspects of macaque social structure. Future directions should include using phylogeographic approaches, and addressing challenges in examining the effects of socioecological factors on primate social structure. © 2017 Wiley Periodicals, Inc.

Designing Industrial Networks Using Ecological Food Web Metrics.

PubMed

Layton, Astrid; Bras, Bert; Weissburg, Marc

2016-10-18

Biologically Inspired Design (biomimicry) and Industrial Ecology both look to natural systems to enhance the sustainability and performance of engineered products, systems and industries. Bioinspired design (BID) traditionally has focused on a unit operation and single product level. In contrast, this paper describes how principles of network organization derived from analysis of ecosystem properties can be applied to industrial system networks. Specifically, this paper examines the applicability of particular food web matrix properties as design rules for economically and biologically sustainable industrial networks, using an optimization model developed for a carpet recycling network. Carpet recycling network designs based on traditional cost and emissions based optimization are compared to designs obtained using optimizations based solely on ecological food web metrics. The analysis suggests that networks optimized using food web metrics also were superior from a traditional cost and emissions perspective; correlations between optimization using ecological metrics and traditional optimization ranged generally from 0.70 to 0.96, with flow-based metrics being superior to structural parameters. Four structural food parameters provided correlations nearly the same as that obtained using all structural parameters, but individual structural parameters provided much less satisfactory correlations. The analysis indicates that bioinspired design principles from ecosystems can lead to both environmentally and economically sustainable industrial resource networks, and represent guidelines for designing sustainable industry networks.

Electric Industry Structure and Regulatory Responses in a High Distributed Energy Resources Future

DOE Office of Scientific and Technical Information (OSTI.GOV)

Corneli, Steve; Kihm, Steve; Schwartz, Lisa

The emergence of distributed energy resources (DERs) that can generate, manage and store energy on the customer side of the electric meter is widely recognized as a transformative force in the power sector. This report focuses on two key aspects of that transformation: structural changes in the electric industry and related changes in business organization and regulation that are likely to result from them. Both industry structure and regulation are inextricably linked. History shows that the regulation of the power sector has responded primarily to innovation in technologies and business models that created significant structural changes in the sector’s costmore » and organizational structure.« less

Investigation of structure and mechanical properties of plasma vapor deposited nanocomposite TiBN films

NASA Astrophysics Data System (ADS)

Han, Bin; Neena, D.; Wang, Zesong; Kondamareddy, K. k.; Li, Na; Zuo, Wenbin; Yan, Shaojian; Liu, Chuansheng; Fu, Dejun

2017-04-01

TiBN coatings have huge potential applications as they have excellent properties with increasing modern industrial requirements. Nanocomposite TiBN coatings were synthesized on cemented carbide, high speed steel and Si substrates by using cathodic arc plasma ion plating from pure TiB2 ceramic targets. The structure and mechanical properties of the TiBN coatings were significantly influenced by the nitrogen partial pressure. Rutherford backscattering spectrometry demonstrates that the nitrogen content of the coating varied from 2.8% to 34.5% and high-resolution electron microscopy images reveal that all coatings have the characteristic of nanocrystals embedded in an amorphous matrix. The root-mean-square roughness of the coatings increases from 3.73 to 14.64 nm and the coefficients of friction of the coatings at room temperature vary from 0.54 to 0.73 with increasing nitrogen partial pressure. The microhardness of the coating increases up to 35.7 GPa at 10 sccm N2 flow rate. The smallest wear rate is 2.65 × 10-15 m3 N-1 m-1 which indicates that TiBN coatings have excellent wear resistance. The adhesion test revealed that the TiBN coatings have good adhesion at low nitrogen partial pressure.

Enhanced properties of tungsten thin films deposited with a novel HiPIMS approach

NASA Astrophysics Data System (ADS)

Velicu, Ioana-Laura; Tiron, Vasile; Porosnicu, Corneliu; Burducea, Ion; Lupu, Nicoleta; Stoian, George; Popa, Gheorghe; Munteanu, Daniel

2017-12-01

Despite the tremendous potential for industrial use of tungsten (W), very few studies have been reported so far on controlling and tailoring the properties of W thin films obtained by physical vapor deposition techniques and, even less, for those deposited by High Power Impulse Magnetron Sputtering (HiPIMS). This study presents results on the deposition process and properties characterization of nanocrystalline W thin films deposited on silicon and molybdenum substrates (100 W average sputtering power) by conventional dc magnetron sputtering (dcMS) and HiPIMS techniques. Topological, structural, mechanical and tribological properties of the deposited thin films were investigated. It was found that in HiPIMS, both deposition process and coatings properties may be optimized by using an appropriate magnetic field configuration and pulsing design. Compared to the other deposited samples, the W films grown in multi-pulse (5 × 3 μs) HiPIMS assisted by an additional magnetic field, created with a toroidal-shaped permanent magnet placed in front of the magnetron cathode, show significantly enhanced properties, such as: smoother surfaces, higher homogeneity and denser microstructure, higher hardness and Young's modulus values, better adhesion to the silicon substrate and lower coefficient of friction. Mechanical behaviour and structural changes are discussed based on plasma diagnostics results.

Performance analyses of helical coil heat exchangers. The effect of external coil surface modification on heat exchanger effectiveness

NASA Astrophysics Data System (ADS)

Andrzejczyk, Rafał; Muszyński, Tomasz

2016-12-01

The shell and coil heat exchangers are commonly used in heating, ventilation, nuclear industry, process plant, heat recovery and air conditioning systems. This type of recuperators benefits from simple construction, the low value of pressure drops and high heat transfer. In helical coil, centrifugal force is acting on the moving fluid due to the curvature of the tube results in the development. It has been long recognized that the heat transfer in the helical tube is much better than in the straight ones because of the occurrence of secondary flow in planes normal to the main flow inside the helical structure. Helical tubes show good performance in heat transfer enhancement, while the uniform curvature of spiral structure is inconvenient in pipe installation in heat exchangers. Authors have presented their own construction of shell and tube heat exchanger with intensified heat transfer. The purpose of this article is to assess the influence of the surface modification over the performance coefficient and effectiveness. The experiments have been performed for the steady-state heat transfer. Experimental data points were gathered for both laminar and turbulent flow, both for co current- and countercurrent flow arrangement. To find optimal heat transfer intensification on the shell-side authors applied the number of transfer units analysis.

Structural equation modeling of PAHs in ambient air, dust fall, soil, and cabbage in vegetable bases of Northern China.

PubMed

Zhang, YunHui; Hou, DeYi; Xiong, GuanNan; Duan, YongHong; Cai, ChuanYang; Wang, Xin; Li, JingYa; Tao, Shu; Liu, WenXin

2018-08-01

A series of field samples including ambient air (gaseous and particulate phases), dust fall, surface soil, rhizosphere soil and cabbage tissues (leaf, root and core), were collected in vegetable bases near a large coking manufacturer in Shanxi Province, Northern China, during a harvest season. A factor analysis was employed to apportion the emission sources of polycyclic aromatic hydrocarbons (PAHs), and the statistical results indicated coal combustion was the dominant emission source that accounted for different environmental media and cabbage tissues, while road traffic, biomass burning and the coking industry contributed to a lesser extent. A structural equation model was first developed to quantitatively explore the transport pathways of PAHs from surrounding media to cabbage tissues. The modeling results showed that PAHs in ambient air were positively associated with those in dust fall, and a close relationship was also true for PAHs in dust fall and in surface soil due to air-soil exchange process. Furthermore, PAHs in surface soil were correlated with those in rhizosphere soil and in the cabbage leaf with the path coefficients of 0.83 and 0.39, respectively. PAHs in the cabbage leaf may dominantly contribute to the accumulation of PAHs in the edible part of cabbages. Copyright © 2018 Elsevier Ltd. All rights reserved.

An examination of loads and responses of a wind turbine undergoing variable-speed operation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wright, A.D.; Buhl, M.L. Jr.; Bir, G.S.

1996-11-01

The National Renewable Energy Laboratory has recently developed the ability to predict turbine loads and responses for machines undergoing variable-speed operation. The wind industry has debated the potential benefits of operating wind turbine sat variable speeds for some time. Turbine system dynamic responses (structural response, resonance, and component interactions) are an important consideration for variable-speed operation of wind turbines. The authors have implemented simple, variable-speed control algorithms for both the FAST and ADAMS dynamics codes. The control algorithm is a simple one, allowing the turbine to track the optimum power coefficient (C{sub p}). The objective of this paper is tomore » show turbine loads and responses for a particular two-bladed, teetering-hub, downwind turbine undergoing variable-speed operation. The authors examined the response of the machine to various turbulent wind inflow conditions. In addition, they compare the structural responses under fixed-speed and variable-speed operation. For this paper, they restrict their comparisons to those wind-speed ranges for which limiting power by some additional control strategy (blade pitch or aileron control, for example) is not necessary. The objective here is to develop a basic understanding of the differences in loads and responses between the fixed-speed and variable-speed operation of this wind turbine configuration.« less

Growth of highly textured PbTiO3 films on conductive substrate under hydrothermal conditions

NASA Astrophysics Data System (ADS)

Tang, Haixiong; Zhou, Zhi; Bowland, Christopher C.; Sodano, Henry A.

2015-08-01

Perovskite structure (ABO3) thin films have wide applications in electronic devices due to their unique properties, including high dielectric permittivity, ferroelectricity and piezoelectric coupling. Here, we report an approach to grow highly textured thick lead titanate (PbTiO3) films on conductive substrates by a two-step hydrothermal reaction. Initially, vertically aligned TiO2 nanowire arrays are grown on fluorine-doped tin oxide (FTO) coated glass, which act as template crystals for conversion to the perovskite structure. The PbTiO3 films are then converted from TiO2 NW arrays by diffusing Pb2+ ions into the template through a second hydrothermal reaction. The dielectric permittivity and piezoelectric coupling coefficient (d33) of the PbTiO3 films are as high as 795 at 1 kHz and 52 pm V-1, respectively. The reported process can also potentially be expanded for the assembly of other complex perovskite ATiO3 (A = Ba, Ca, Cd, etc) films by using the highly aligned TiO2 NW arrays as templates. Therefore, the approach introduced here opens up a new door to synthesize ferroelectric thin films on conductive substrates for application in sensors, actuators, and ultrasonic transducers that are important in various industrial and scientific areas.

Thermal barrier coatings on gas turbine blades: Chemical vapor deposition (Review)

NASA Astrophysics Data System (ADS)

Igumenov, I. K.; Aksenov, A. N.

2017-12-01

Schemes are presented for experimental setups (reactors) developed at leading scientific centers connected with the development of technologies for the deposition of coatings using the CVD method: at the Technical University of Braunschweig (Germany), the French Aerospace Research Center, the Materials Research Institute (Tohoku University, Japan) and the National Laboratory Oak Ridge (USA). Conditions and modes for obtaining the coatings with high operational parameters are considered. It is established that the formed thermal barrier coatings do not fundamentally differ in their properties (columnar microstructure, thermocyclic resistance, thermal conductivity coefficient) from standard electron-beam condensates, but the highest growth rates and the perfection of the crystal structure are achieved in the case of plasma-chemical processes and in reactors with additional laser or induction heating of a workpiece. It is shown that CVD reactors can serve as a basis for the development of rational and more advanced technologies for coating gas turbine blades that are not inferior to standard electron-beam plants in terms of the quality of produced coatings and have a much simpler and cheaper structure. The possibility of developing a new technology based on CVD processes for the formation of thermal barrier coatings with high operational parameters is discussed, including a set of requirements for industrial reactors, high-performance sources of vapor precursors, and promising new materials.

Porous composite with negative thermal expansion obtained by photopolymer additive manufacturing

NASA Astrophysics Data System (ADS)

Takezawa, Akihiro; Kobashi, Makoto; Kitamura, Mitsuru

2015-07-01

Additive manufacturing (AM) could be a novel method of fabricating composite and porous materials having various effective performances based on mechanisms of their internal geometries. Materials fabricated by AM could rapidly be used in industrial application since they could easily be embedded in the target part employing the same AM process used for the bulk material. Furthermore, multi-material AM has greater potential than usual single-material AM in producing materials with effective properties. Negative thermal expansion is a representative effective material property realized by designing a composite made of two materials with different coefficients of thermal expansion. In this study, we developed a porous composite having planar negative thermal expansion by employing multi-material photopolymer AM. After measurement of the physical properties of bulk photopolymers, the internal geometry was designed by topology optimization, which is the most effective structural optimization in terms of both minimizing thermal stress and maximizing stiffness. The designed structure was converted to a three-dimensional stereolithography (STL) model, which is a native digital format of AM, and assembled as a test piece. The thermal expansions of the specimens were measured using a laser scanning dilatometer. Negative thermal expansion corresponding to less than -1 × 10-4 K-1 was observed for each test piece of the N = 3 experiment.

Quantitative correlations between collision induced dissociation mass spectrometry coupled with electrospray ionization or atmospheric pressure chemical ionization mass spectrometry - Experiment and theory

NASA Astrophysics Data System (ADS)

Ivanova, Bojidarka; Spiteller, Michael

2018-04-01

The problematic that we consider in this paper treats the quantitative correlation model equations between experimental kinetic and thermodynamic parameters of coupled electrospray ionization (ESI) mass spectrometry (MS) or atmospheric pressure chemical ionization (APCI) mass spectrometry with collision induced dissociation mass spectrometry, accounting for the fact that the physical phenomena and mechanisms of ESI- and APCI-ion formation are completely different. There are described forty two fragment reactions of three analytes under independent ESI- and APCI-measurements. The developed new quantitative models allow us to study correlatively the reaction kinetics and thermodynamics using the methods of mass spectrometry, which complementary application with the methods of the quantum chemistry provide 3D structural information of the analytes. Both static and dynamic quantum chemical computations are carried out. The object of analyses are [2,3-dimethyl-4-(4-methyl-benzoyl)-2,3-di-p-tolyl-cyclobutyl]-p-tolyl-methanone (1) and the polycyclic aromatic hydrocarbons derivatives of dibenzoperylen (2) and tetrabenzo [a,c,fg,op]naphthacene (3), respectively. As far as (1) is known to be a product of [2π+2π] cycloaddition reactions of chalcone (1,3-di-p-tolyl-propenone), however producing cyclic derivatives with different stereo selectivity, so that the study provide crucial data about the capability of mass spectrometry to provide determine the stereo selectivity of the analytes. This work also first provides quantitative treatment of the relations '3D molecular/electronic structures'-'quantum chemical diffusion coefficient'-'mass spectrometric diffusion coefficient', thus extending the capability of the mass spectrometry for determination of the exact 3D structure of the analytes using independent measurements and computations of the diffusion coefficients. The determination of the experimental diffusion parameters is carried out within the 'current monitoring method' evaluating the translation diffusion of charged analytes, while the theoretical modelling of MS ions and computations of theoretical diffusion coefficients are based on the Arrhenius type behavior of the charged species under ESI- and APCI-conditions. Although the study provide certain sound considerations for the quantitative relations between the reaction kinetic-thermodynamics and 3D structure of the analytes together with correlations between 3D molecular/electronic structures-quantum chemical diffusion coefficient-mass spectrometric diffusion coefficient, which contribute significantly to the structural analytical chemistry, the results have importance to other areas such as organic synthesis and catalysis as well.

Strategic Use of Random Subsample Replication and a Coefficient of Factor Replicability

ERIC Educational Resources Information Center

Katzenmeyer, William G.; Stenner, A. Jackson

1975-01-01

The problem of demonstrating replicability of factor structure across random variables is addressed. Procedures are outlined which combine the use of random subsample replication strategies with the correlations between factor score estimates across replicate pairs to generate a coefficient of replicability and confidence intervals associated with…

PREDICTING SOIL SORPTION COEFFICIENTS OF ORGANIC CHEMICALS USING A NEURAL NETWORK MODEL

EPA Science Inventory

The soil/sediment adsorption partition coefficient normalized to organic carbon (K_oc) is extensively used to assess the fate of organic chemicals in hazardous waste sites. Several attempts have been made to estimate the value of K_oc from chemical structure ...

Subcortical structure segmentation using probabilistic atlas priors

NASA Astrophysics Data System (ADS)

Gouttard, Sylvain; Styner, Martin; Joshi, Sarang; Smith, Rachel G.; Cody Hazlett, Heather; Gerig, Guido

2007-03-01

The segmentation of the subcortical structures of the brain is required for many forms of quantitative neuroanatomic analysis. The volumetric and shape parameters of structures such as lateral ventricles, putamen, caudate, hippocampus, pallidus and amygdala are employed to characterize a disease or its evolution. This paper presents a fully automatic segmentation of these structures via a non-rigid registration of a probabilistic atlas prior and alongside a comprehensive validation. Our approach is based on an unbiased diffeomorphic atlas with probabilistic spatial priors built from a training set of MR images with corresponding manual segmentations. The atlas building computes an average image along with transformation fields mapping each training case to the average image. These transformation fields are applied to the manually segmented structures of each case in order to obtain a probabilistic map on the atlas. When applying the atlas for automatic structural segmentation, an MR image is first intensity inhomogeneity corrected, skull stripped and intensity calibrated to the atlas. Then the atlas image is registered to the image using an affine followed by a deformable registration matching the gray level intensity. Finally, the registration transformation is applied to the probabilistic maps of each structures, which are then thresholded at 0.5 probability. Using manual segmentations for comparison, measures of volumetric differences show high correlation with our results. Furthermore, the dice coefficient, which quantifies the volumetric overlap, is higher than 62% for all structures and is close to 80% for basal ganglia. The intraclass correlation coefficient computed on these same datasets shows a good inter-method correlation of the volumetric measurements. Using a dataset of a single patient scanned 10 times on 5 different scanners, reliability is shown with a coefficient of variance of less than 2 percents over the whole dataset. Overall, these validation and reliability studies show that our method accurately and reliably segments almost all structures. Only the hippocampus and amygdala segmentations exhibit relative low correlation with the manual segmentation in at least one of the validation studies, whereas they still show appropriate dice overlap coefficients.

Employer-sponsored insurance, health care cost growth, and the economic performance of U.S. Industries.

PubMed

Sood, Neeraj; Ghosh, Arkadipta; Escarce, José J

2009-10-01

To estimate the effect of growth in health care costs that outpaces gross domestic product (GDP) growth ("excess" growth in health care costs) on employment, gross output, and value added to GDP of U.S. industries. We analyzed data from 38 U.S. industries for the period 1987-2005. All data are publicly available from various government agencies. We estimated bivariate and multivariate regressions. To develop the regression models, we assumed that rapid growth in health care costs has a larger effect on economic performance for industries where large percentages of workers receive employer-sponsored health insurance (ESI). We used the estimated regression coefficients to simulate economic outcomes under alternative scenarios of health care cost inflation. Faster growth in health care costs had greater adverse effects on economic outcomes for industries with larger percentages of workers who had ESI. We found that a 10 percent increase in excess growth in health care costs would have resulted in 120,803 fewer jobs, US$28,022 million in lost gross output, and US$14,082 million in lost value added in 2005. These declines represent 0.17 to 0.18 percent of employment, gross output, and value added in 2005. Excess growth in health care costs is adversely affecting the economic performance of U.S. industries.

Southeast Asia Report

DTIC Science & Technology

1986-03-10

culture with the consumer goods industry and with heavy industry to build a rational agriculture- industry structure." Comprising the food ...only self-sufficient in ’ food but has even accumulated some reserves. Output of agricultural products and Industrial crops: Coffee... Industry Before liberation in 1975, Lao industry mainly consisted of a few factories producing consumer goods. Industrial output accounted for a

The Forecast of Baoding’s Industrial Structure in Different Scenarios

NASA Astrophysics Data System (ADS)

Li, Wei; Zhang, Hongzhi; Zhang, Shu

2018-01-01

In November 12th, 2014, Chinese government officially announced reaching the peak of CO2 emissions around 2030. Baoding, as one of the first low-carbon pilot cities in China, bore an important mission and set an example to other cities to reach the peak of carbon emissions before 2030. This paper employed a computable general equilibrium model to simulate the industrial structure and social welfare of Baoding in different scenarios. And the calculation results have shown that on the principle of the optimal industrial structure and the minimum social welfare loss and a consideration of industrial economic development, the best time of CO2 emissions peak for Baoding was 2025 when its total emissions would reach 2.84 million tons. Finally, some suggestions were given to guide this city to reduce carbon emissions in industrial development.

Piezoelectric shear wave resonator and method of making same

DOEpatents

Wang, J.S.; Lakin, K.M.; Landin, A.R.

1985-05-20

An acoustic shear wave resonator comprising a piezoelectric film having its C-axis substantially inclined from the film normal such that the shear wave coupling coefficient significantly exceeds the longitudinal wave coupling coefficient, whereby the film is capable of shear wave resonance, and means for exciting said film to resonate. The film is prepared by deposition in a dc planar magnetron sputtering system to which a supplemental electric field is applied. The resonator structure may also include a semiconductor material having a positive temperature coefficient of resonance such that the resonator has a temperature coefficient of resonance approaching 0 ppM//sup 0/C.

Piezoelectric shear wave resonator and method of making same

DOEpatents

Wang, J.S.; Lakin, K.M.; Landin, A.R.

1983-10-25

An acoustic shear wave resonator comprising a piezoelectric film having its C-axis substantially inclined from the film normal such that the shear wave coupling coefficient significantly exceeds the longitudinal wave coupling coefficient, whereby the film is capable of shear wave resonance, and means for exciting said film to resonate. The film is prepared by deposition in a dc planar magnetron sputtering system to which a supplemental electric field is applied. The resonator structure may also include a semiconductor material having a positive temperature coefficient of resonance such that the resonator has a temperature coefficient of resonance approaching 0 ppM//sup 0/C.

Evaluation of FUS-2000 urine analyzer: analytical properties and particle recognition.

PubMed

Beňovská, Miroslava; Wiewiorka, Ondřej; Pinkavová, Jana

This study evaluates the performance of microscopic part of a hybrid analyzer FUS-2000 (Dirui Industrial Co., Changchun, China), its analytical properties and particle recognition. The evaluation of trueness, repeatability, detection limit, carry-over, linearity range and analytical stability was performed according to Dirui protocol guidelines designed by Dirui Company to guarantee the quality of the instrument. Trueness for low, medium and high-value concentrations was calculated with bias of 15.5, 4.7 and -6.6%, respectively. Detection limit of 5 Ery/μl was confirmed. Coefficient of variation of 11.0, 5.2 and 3.8% was measured for within-run repeatability of low, medium and high concentration. Between-run repeatability for daily quality control had coefficient of variation of 3.0%. Carry-over did not exceed 0.05%. Linearity was confirmed for range of 0-16,000 particles/μl (R 2  = 0.9997). The analytical stability had coefficient of variation of 4.3%. Out of 1258 analyzed urine samples, 362 positive were subjected to light microscopy urine sediment analysis and compared to the analyzer results. Cohen's kappa coefficients were calculated to express the concordance. Squared kappa coefficient was 0.927 (red blood cells), 0.888 (white blood cells), 0.908 (squamous epithelia), 0.634 (transitional epithelia), 0.628 (hyaline casts), 0.843 (granular casts) and 0.623 (bacteria). Single kappa coefficients were 0.885 (yeasts) and 0.756 (crystals), respectively. Aforementioned results show good analytical performance of the analyzer and tight agreement with light microscopy of urine sediment.

A summary of modulus of elasticity and knot size surveys for laminating grades of lumber

Treesearch

R. W. Wolfe; R. C. Moody

1981-01-01

A summary of modulus of elasticity (MOE) and knot data is presented for grades of lumber commonly used to manufacture glued-laminated (glulam) timber by the laminating Industry. Tabulated values represent 30 different studies covering a time span of over 16 years. Statistical estimates of average and near-maximum knot sizes as well as mean and coefficient of variation...

Future Performance Trend Indicators: A Current Value Approach to Human Resources Accounting. Report III. Multivariate Predictions of Organizational Performance Across Time.

ERIC Educational Resources Information Center

Pecorella, Patricia A.; Bowers, David G.

Multiple regression in a double cross-validated design was used to predict two performance measures (total variable expense and absence rate) by multi-month period in five industrial firms. The regressions do cross-validate, and produce multiple coefficients which display both concurrent and predictive effects, peaking 18 months to two years…

The Bach equations in spin-coefficient form

NASA Astrophysics Data System (ADS)

Forbes, Hamish

2018-06-01

Conformal gravity theories are defined by field equations that determine only the conformal structure of the spacetime manifold. The Bach equations represent an early example of such a theory, we present them here in component form in terms of spin- and boost-weighted spin-coefficients using the compacted spin-coefficient formalism. These equations can be used as an efficient alternative to the standard tensor form. As a simple application we solve the Bach equations for pp-wave and static spherically symmetric spacetimes.

Piezoelectric films for acoustoelectronic devices - Production, properties, and applications

NASA Astrophysics Data System (ADS)

Anisimkin, V. I.; Kotelianskii, I. M.

1990-06-01

Various aspects of the production of ZnO, AlN, and Ta2O5 piezoelectric films are briefly reviewed. The mininum possible absorption coefficient of surface acoustic waves in textured films is estimated theoretically with allowance for different absorption mechanisms. The results obtained are compared with those for single crystals of the same materials. Methods for calculating the absorption coefficient and temperature delay coefficient for Rayleigh and Sezawa surface acoustic waves in layered structures are proposed and verified experimentally.

Thermodynamic properties and diffusion of water + methane binary mixtures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shvab, I.; Sadus, Richard J., E-mail: rsadus@swin.edu.au

2014-03-14

Thermodynamic and diffusion properties of water + methane mixtures in a single liquid phase are studied using NVT molecular dynamics. An extensive comparison is reported for the thermal pressure coefficient, compressibilities, expansion coefficients, heat capacities, Joule-Thomson coefficient, zero frequency speed of sound, and diffusion coefficient at methane concentrations up to 15% in the temperature range of 298–650 K. The simulations reveal a complex concentration dependence of the thermodynamic properties of water + methane mixtures. The compressibilities, heat capacities, and diffusion coefficients decrease with increasing methane concentration, whereas values of the thermal expansion coefficients and speed of sound increase. Increasing methanemore » concentration considerably retards the self-diffusion of both water and methane in the mixture. These effects are caused by changes in hydrogen bond network, solvation shell structure, and dynamics of water molecules induced by the solvation of methane at constant volume conditions.« less

Kinetics of dodecanoic acid adsorption from caustic solution by activated carbon.

PubMed

Pendleton, Phillip; Wu, Sophie Hua

2003-10-15

This study examines the influences of adsorbent porosity and surface chemistry and of carbon dosage on dodecanoic acid adsorption kinetics from aqueous and 2 M NaOH solutions as batch adsorption processes. Both adsorbents are steam-activated carbons prepared from either coconut or coal precursors. Prior to use the adsorbents were washed in deionized water or 2 M NaOH. Mass transfer coefficients and effective overall diffusion coefficients indicate a minor contribution from adsorbent porosity. In contrast, high surface oxygen content impedes transport to and into the adsorbent structure. Carbon dosage shows a proportional increase in transport coefficients with increasing mass; these coefficients are constant when normalized per unit mass. Neither water nor NaOH treatment of the adsorbents has a significant influence on dodecanoic acid adsorption kinetics. Molecular and Knudsen diffusion coefficients are defined to demonstrate that the overall effective diffusion coefficient values and the diffusion process are controlled by surface diffusion.

NGA-West 2 GMPE average site coefficients for use in earthquake-resistant design

USGS Publications Warehouse

Borcherdt, Roger D.

2015-01-01

Site coefficients corresponding to those in tables 11.4–1 and 11.4–2 of Minimum Design Loads for Buildings and Other Structures published by the American Society of Civil Engineers (Standard ASCE/SEI 7-10) are derived from four of the Next Generation Attenuation West2 (NGA-W2) Ground-Motion Prediction Equations (GMPEs). The resulting coefficients are compared with those derived by other researchers and those derived from the NGA-West1 database. The derivation of the NGA-W2 average site coefficients provides a simple procedure to update site coefficients with each update in the Maximum Considered Earthquake Response MCER maps. The simple procedure yields average site coefficients consistent with those derived for site-specific design purposes. The NGA-W2 GMPEs provide simple scale factors to reduce conservatism in current simplified design procedures.

Implications of New Methane Absorption Coefficients on Uranus Vertical Structure Derived from Near-IR Spectra

NASA Astrophysics Data System (ADS)

Fry, Patrick M.; Sromovsky, L. A.

2009-09-01

Using new methane absorption coefficients from Karkoschka and Tomasko (2009, submitted to Icarus, "Methane Absorption Coefficients for the Jovian Planets from Laboratory, Huygens, and HST Data"), we fit Uranus near-IR spectra previously analyzed in Sromovsky et al. (2006, Icarus 182, 577-593, Fink and Larson, 1979 J- and H-band), Sromovsky and Fry (2008, Icarus 193, 252-266, 2006 NIRC2 J- and H-band, 2006 SpeX) using Irwin et al. (2006, Icarus 181, 309-319) methane absorption coefficients. Because the new absorption coefficients usually result in higher opacities at the low temperatures seen in Uranus' upper troposphere, our previously derived cloud altitudes are expected to generally rise to higher altitudes. For example, using Lindal et al. (1987, JGR 92, 14987-15001) model D temperature and methane abundance profiles, we are better able to fit the J-band 43-deg. south bright band with the new coefficients (chi-square=205, vs. 315 for Irwin), with the pressure of the upper tropospheric cloud decreasing to 1.6 bars (from 2.4 bars using Irwin coefficients). Improvements in fitting H-band spectra from the same latitude are not as readily obtained. Derived upper tropospheric cloud pressures are very similar using the two absorption datasets (1.6-1.7 bars), but the character of the fits differs. New Karkoschka and Tomasko coefficients better fit some details in the 1.5-1.58 micron region, but Irwin fits the broad absorption band wing at 1.61-1.62 microns better, and the fit chi-square values are similar (K&T: 243, Irwin: 220). Results for a higher methane concentration (Lindal et al. model F) were similar. Whether the new coefficients will simply raise derived altitudes across the planet or will result in fundamental changes in structure is as yet unclear. This work was suported by NASA planetary astronomy and planetary atmospheres programs.

Multiple lesion track structure model

NASA Technical Reports Server (NTRS)

Wilson, John W.; Cucinotta, Francis A.; Shinn, Judy L.

1992-01-01

A multilesion cell kinetic model is derived, and radiation kinetic coefficients are related to the Katz track structure model. The repair-related coefficients are determined from the delayed plating experiments of Yang et al. for the C3H10T1/2 cell system. The model agrees well with the x ray and heavy ion experiments of Yang et al. for the immediate plating, delaying plating, and fractionated exposure protocols employed by Yang. A study is made of the effects of target fragments in energetic proton exposures and of the repair-deficient target-fragment-induced lesions.

Pattern formation without diffraction matching in optical parametric oscillators with a metamaterial.

PubMed

Tassin, Philippe; Van der Sande, Guy; Veretennicoff, Irina; Kockaert, Pascal; Tlidi, Mustapha

2009-05-25

We consider a degenerate optical parametric oscillator containing a left-handed material. We show that the inclusion of a left-handed material layer allows for controlling the strength and sign of the diffraction coefficient at either the pump or the signal frequency. Subsequently, we demonstrate the existence of stable dissipative structures without diffraction matching, i.e., without the usual relationship between the diffraction coefficients of the signal and pump fields. Finally, we investigate the size scaling of these light structures with decreasing diffraction strength.

Composite fastener for use in high temperature environments

NASA Technical Reports Server (NTRS)

Miller, Robert J. (Inventor); Palusis, Mark E. (Inventor); Jarmon, David C. (Inventor)

2000-01-01

A fastener includes a composite body and a metal coupling attached to the body. The metal coupling includes an attachment structure to connect the fastener to an external structure. An assembly of components includes a first metallic component having a first coefficient of thermal expansion, a second non-metallic component having a second coefficient of thermal expansion different from the first thermal expansion and having a groove that receives a fastener that extends between the groove and the second component, the fastener slidably engaging the groove to accommodate relative expansion between the components.

The Effects of ph on Structural and Optical Characterization of Iron Oxide Thin Films

NASA Astrophysics Data System (ADS)

Tezel, Fatma Meydaneri; Özdemir, Osman; Kariper, I. Afşin

In this study, the iron oxide thin films have been produced by chemical bath deposition (CBD) method as a function of pH onto amorphous glass substrates. The surface images of the films were investigated with scanning electron microscope (SEM). The crystal structures, orientation of crystallization, crystallite sizes, and dislocation density i.e. structural properties of the thin films were analyzed with X-ray diffraction (XRD). The optical band gap (Eg), optical transmission (T%), reflectivity (R%), absorption coefficient (α), refraction index (n), extinction coefficient (k) and dielectric constant (ɛ) of the thin films were investigated depending on pH, deposition time, solution temperature, substrate temperature, thickness of the films by UV-VIS spectrometer.

Ab initio study of II-(VI)2 dichalcogenides.

PubMed

Olsson, P; Vidal, J; Lincot, D

2011-10-12

The structural stabilities of the (Zn,Cd)(S,Se,Te)(2) dichalcogenides have been determined ab initio. These compounds are shown to be stable in the pyrite phase, in agreement with available experiments. Structural parameters for the ZnTe(2) pyrite semiconductor compound proposed here are presented. The opto-electronic properties of these dichalcogenide compounds have been calculated using quasiparticle GW theory. Bandgaps, band structures and effective masses are proposed as well as absorption coefficients and refraction indices. The compounds are all indirect semiconductors with very flat conduction band dispersion and high absorption coefficients. The work functions and surface properties are predicted. The Te and Se based compounds could be of interest as absorber materials in photovoltaic applications.

Temperature and pressure dependence of dichloro-difluoromethane (CF2C12) absorption coefficients for CO2 waveguide laser radiation

NASA Technical Reports Server (NTRS)

Harward, C. N.

1977-01-01

Measurements were performed to determine the pressure and temperature dependence of CFM-12 absorption coefficients for CO2 waveguide laser radiation. The absorption coefficients of CFM-12 for CO2 waveguide laser radiation were found to have no spectral structure within small spectral bandwidths around the CO2 waveguide laser lines in the CO2 spectral band for pressures above 20 torr. All of the absorption coefficients for the CO2 laser lines studied are independent of pressure above 100 torr, except for the P(36) laser CO2 spectral band. The absorption coefficients associated with the P(42) line in the same band showed the greatest change with temperature, and it also has the largest value of all the lines studied.

Multi-photon lithography of 3D micro-structures in As2S3 and Ge5(As2Se3)95 chalcogenide glasses

NASA Astrophysics Data System (ADS)

Schwarz, Casey M.; Labh, Shreya; Barker, Jayk E.; Sapia, Ryan J.; Richardson, Gerald D.; Rivero-Baleine, Clara; Gleason, Benn; Richardson, Kathleen A.; Pogrebnyakov, Alexej; Mayer, Theresa S.; Kuebler, Stephen M.

2016-03-01

This work reports a detailed study of the processing and photo-patterning of two chalcogenide glasses (ChGs) - arsenic trisulfide (As2S3) and a new composition of germanium-doped arsenic triselenide Ge5(As2Se3)95 - as well as their use for creating functional optical structures. ChGs are materials with excellent infrared (IR) transparency, large index of refraction, low coefficient of thermal expansion, and low change in refractive index with temperature. These features make them well suited for a wide range of commercial and industrial applications including detectors, sensors, photonics, and acousto-optics. Photo-patternable films of As2S3 and Ge5(As2Se3)95 were prepared by thermally depositing the ChGs onto silicon substrates. For some As2S3 samples, an anti-reflection layer of arsenic triselenide (As2Se3) was first added to mitigate the effects of standing-wave interference during laser patterning. The ChG films were photo-patterned by multi-photon lithography (MPL) and then chemically etched to remove the unexposed material, leaving free-standing structures that were negative-tone replicas of the photo-pattern in networked-solid ChG. The chemical composition and refractive index of the unexposed and photo-exposed materials were examined using Raman spectroscopy and near-IR ellipsometry. Nano-structured arrays were photo-patterned and the resulting nano-structure morphology and chemical composition were characterized and correlated with the film compositions, conditions of thermal deposition, patterned irradiation, and etch processing. Photo-patterned Ge5(As2Se3)95 was found to be more resistant than As2S3 toward degradation by formation of surface oxides.

United Kingdom Automobile Insurance Market

DOT National Transportation Integrated Search

1979-05-01

The report represents a limited study of the United Kingdom Automobile Insurance Industry: (1) the structure, size, and relationships within the industry; (2) the basis of premium calculation, rate structure, types of policies, and payment of compens...

Dual-Electrode CMUT With Non-Uniform Membranes for High Electromechanical Coupling Coefficient and High Bandwidth Operation

PubMed Central

Guldiken, Rasim O.; Zahorian, Jaime; Yamaner, F. Y.; Degertekin, F. L.

2010-01-01

In this paper, we report measurement results on dual-electrode CMUT demonstrating electromechanical coupling coefficient (k2) of 0.82 at 90% of collapse voltage as well as 136% 3 dB one-way fractional bandwidth at the transducer surface around the design frequency of 8 MHz. These results are within 5% of the predictions of the finite element simulations. The large bandwidth is achieved mainly by utilizing a non-uniform membrane, introducing center mass to the design, whereas the dual-electrode structure provides high coupling coefficient in a large dc bias range without collapsing the membrane. In addition, the non-uniform membrane structure improves the transmit sensitivity of the dual-electrode CMUT by about 2dB as compared with a dual electrode CMUT with uniform membrane. PMID:19574135

Electronic and Transport Properties of LaNi4Sb12 Skutterudite: Modified Becke-Johnson Approach

NASA Astrophysics Data System (ADS)

Bhat, Tahir Mohiuddin; Singh, Srishti; Gupta, Dinesh C.

2018-05-01

We carried out an ab initio study of structural, electronic, thermodynamic, and thermoelectric properties of the lanthanum-filled skutterudite, LaNi4Sb12. Generalized gradient approximation and modified Becke-Johnson potentials were employed for the exchange-correlation potential. The electronic structure calculations display the metallic behavior of the compound. The alloy offers low lattice thermal conductivity along with a high Seebeck coefficient with a value of - 158 (μVK-1) at room temperature. The effect of high pressure and temperature on thermal properties like thermal expansion coefficient, heat capacity, and Grüneisen parameter are also investigated by means of a quasi-harmonic Debye model. The large Seebeck coefficient and high power factor exhibited by LaNi4Sb12 make it an attractive candidate for thermoelectric materials.

Structural and aerodynamic loads and performance measurements of an SA349/2 helicopter with an advanced geometry rotor

NASA Technical Reports Server (NTRS)

Heffernan, Ruth M.; Gaubert, Michel

1986-01-01

A flight test program was conducted to obtain data from an upgraded Gazelle helicopter with an advanced geometry, three bladed rotor. Data were acquired on upper and lower surface chordwise blade pressure, blade bending and torsion moments, and fuselage structural loads. Results are presented from 16 individual flight conditions, including level flights ranging from 10 to 77 m/sec at 50 to 3000 m altitude, turning flights up to 2.0 g, and autorotation. Rotor aerodynamic data include information from 51 pressure transducers distributed chordwise at 75, 88, and 97% radial stations. Individual tranducer pressure coefficients and airfoil section lift and pitching moment coefficients are presented, as are steady state flight condition parameters and time dependence rotor loads. All dynamic data are presented as harmonic analysis coefficients.

Rate-coefficients and polarization results for the electron-impact excitation of Ar+ ion

NASA Astrophysics Data System (ADS)

Srivastava, Rajesh; Dipti, Dipti

2016-05-01

A fully relativistic distorted wave theory has been employed to study the electron impact excitation in Ar+ ion. Results have been obtained for the excitation cross-sections and rate-coefficients for the transitions from the ground state 3p5 (J = 3/2) to fine-structure levels of excited states 3p4 4 s, 3p4 4 p , 3p4 5 s, 3p4 5 p, 3p4 3 d and 3p4 4 d. Polarization of the radiation following the excitation has been calculated using the obtained magnetic sub-level cross-sections. Comparison of the present rate-coefficients is also done with the previously reported theoretical results for some unresolved fine structure transitions. Work is supported by DAE-BRNS Mumbai and CSIR, New Delhi.

Ellipsometry study of optical parameters of AgIn5S8 crystals

NASA Astrophysics Data System (ADS)

Isik, Mehmet; Gasanly, Nizami

2015-12-01

AgIn5S8 crystals grown by Bridgman method were characterized for optical properties by ellipsometry measurements. Spectral dependence of optical parameters; real and imaginary parts of the pseudodielectric function, pseudorefractive index, pseudoextinction coefficient, reflectivity and absorption coefficient were obtained from ellipsometry experiments carried out in the 1.2-6.2 eV range. Direct band gap energy of 1.84 eV was found from the analysis of absorption coefficient vs. photon energy. The oscillator energy, dispersion energy and zero-frequency refractive index, high-frequency dielectric constant values were found from the analysis of the experimental data using Wemple-DiDomenico and Spitzer-Fan models. Crystal structure and atomic composition ratio of the constituent elements in the AgIn5S8 crystal were revealed from structural characterization techniques of X-ray diffraction and energy dispersive spectroscopy.

Fine-structure relaxation of O(3P) induced by collisions with He, H and H2

NASA Astrophysics Data System (ADS)

Lique, F.; Kłos, J.; Alexander, M. H.; Le Picard, S. D.; Dagdigian, P. J.

2018-02-01

The excitation of fine-structure levels of O(3P) by collisions is an important cooling process in the interstellar medium (ISM). We investigate here spin-orbit (de-)excitation of O(3Pj, j = 0, 1, 2) induced by collisions with He, H and H2 based on quantum scattering calculations of the relevant rate coefficients in the 10-1000 K temperature range. The underlying potential energy surfaces are derived from highly correlated abinitio calculations. Significant differences were found with the rate coefficients currently used in astrophysical applications. In particular, our new rate coefficients for collisions with H are up to a factor of 5 lower. Radiative transfer computations allow the assessment of the astrophysical impact of these new rate coefficients. In the case of molecular clouds, the new data are found to increase slightly the flux of the 3P1 → 3P2, while decreasing the flux of the 3P0 → 3P1 line. In the case of atomic clouds, the flux of both lines is predicted to decrease. The new rate coefficients are expected to impact significantly the modelling of cooling in astrophysical environments while also allowing new insights into oxygen chemistry in the ISM.

Industrial Archaeology, Landscapes, and Historical Knowledge of Sustainability

Treesearch

Donald L. Hardesty

2006-01-01

The emergence of industrial life support systems in the last three centuries dramatically changed humanenvironmental relationships. Industrial landscapes are repositories of historical knowledge about this ecological revolution. The key components of industrial landscapes include landforms (for example, waste rock dumps from mines), industrial buildings and structures...

The Use of Structure Coefficients to Address Multicollinearity in Sport and Exercise Science

ERIC Educational Resources Information Center

Yeatts, Paul E.; Barton, Mitch; Henson, Robin K.; Martin, Scott B.

2017-01-01

A common practice in general linear model (GLM) analyses is to interpret regression coefficients (e.g., standardized ß weights) as indicators of variable importance. However, focusing solely on standardized beta weights may provide limited or erroneous information. For example, ß weights become increasingly unreliable when predictor variables are…

Control of optical bandgap energy and optical absorption coefficient by geometric parameters in sub-10 nm silicon-nanodisc array structure

NASA Astrophysics Data System (ADS)

Fairuz Budiman, Mohd; Hu, Weiguo; Igarashi, Makoto; Tsukamoto, Rikako; Isoda, Taiga; Itoh, Kohei M.; Yamashita, Ichiro; Murayama, Akihiro; Okada, Yoshitaka; Samukawa, Seiji

2012-02-01

A sub-10 nm, high-density, periodic silicon-nanodisc (Si-ND) array has been fabricated using a new top-down process, which involves a 2D array bio-template etching mask made of Listeria-Dps with a 4.5 nm diameter iron oxide core and damage-free neutral-beam etching (Si-ND diameter: 6.4 nm). An Si-ND array with an SiO2 matrix demonstrated more controllable optical bandgap energy due to the fine tunability of the Si-ND thickness and diameter. Unlike the case of shrinking Si-ND thickness, the case of shrinking Si-ND diameter simultaneously increased the optical absorption coefficient and the optical bandgap energy. The optical absorption coefficient became higher due to the decrease in the center-to-center distance of NDs to enhance wavefunction coupling. This means that our 6 nm diameter Si-ND structure can satisfy the strict requirements of optical bandgap energy control and high absorption coefficient for achieving realistic Si quantum dot solar cells.

Optimized nonorthogonal transforms for image compression.

PubMed

Guleryuz, O G; Orchard, M T

1997-01-01

The transform coding of images is analyzed from a common standpoint in order to generate a framework for the design of optimal transforms. It is argued that all transform coders are alike in the way they manipulate the data structure formed by transform coefficients. A general energy compaction measure is proposed to generate optimized transforms with desirable characteristics particularly suited to the simple transform coding operation of scalar quantization and entropy coding. It is shown that the optimal linear decoder (inverse transform) must be an optimal linear estimator, independent of the structure of the transform generating the coefficients. A formulation that sequentially optimizes the transforms is presented, and design equations and algorithms for its computation provided. The properties of the resulting transform systems are investigated. In particular, it is shown that the resulting basis are nonorthogonal and complete, producing energy compaction optimized, decorrelated transform coefficients. Quantization issues related to nonorthogonal expansion coefficients are addressed with a simple, efficient algorithm. Two implementations are discussed, and image coding examples are given. It is shown that the proposed design framework results in systems with superior energy compaction properties and excellent coding results.

Kinetics and equilibrium of solute diffusion into human hair.

PubMed

Wang, Liming; Chen, Longjian; Han, Lujia; Lian, Guoping

2012-12-01

The uptake kinetics of five molecules by hair has been measured and the effects of pH and physical chemical properties of molecules were investigated. A theoretical model is proposed to analyze the experimental data. The results indicate that the binding affinity of solute to hair, as characterized by hair-water partition coefficient, scales to the hydrophobicity of the solute and decreases dramatically as the pH increases to the dissociation constant. The effective diffusion coefficient of solute depended not only on the molecular size as most previous studies suggested, but also on the binding affinity as well as solute dissociation. It appears that the uptake of molecules by hair is due to both hydrophobic interaction and ionic charge interaction. Based on theoretical considerations of the cellular structure, composition and physical chemical properties of hair, quantitative-structure-property-relationships (QSPR) have been proposed to predict the hair-water partition coefficient (PC) and the effective diffusion coefficient (D (e)) of solute. The proposed QSPR models fit well with the experimental data. This paper could be taken as a reference for investigating the adsorption properties for polymeric materials, fibres, and biomaterials.

Revisiting crash spatial heterogeneity: A Bayesian spatially varying coefficients approach.

PubMed

Xu, Pengpeng; Huang, Helai; Dong, Ni; Wong, S C

2017-01-01

This study was performed to investigate the spatially varying relationships between crash frequency and related risk factors. A Bayesian spatially varying coefficients model was elaborately introduced as a methodological alternative to simultaneously account for the unstructured and spatially structured heterogeneity of the regression coefficients in predicting crash frequencies. The proposed method was appealing in that the parameters were modeled via a conditional autoregressive prior distribution, which involved a single set of random effects and a spatial correlation parameter with extreme values corresponding to pure unstructured or pure spatially correlated random effects. A case study using a three-year crash dataset from the Hillsborough County, Florida, was conducted to illustrate the proposed model. Empirical analysis confirmed the presence of both unstructured and spatially correlated variations in the effects of contributory factors on severe crash occurrences. The findings also suggested that ignoring spatially structured heterogeneity may result in biased parameter estimates and incorrect inferences, while assuming the regression coefficients to be spatially clustered only is probably subject to the issue of over-smoothness. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of the bipartite structure of a network on performance of recommenders

NASA Astrophysics Data System (ADS)

Wang, Qing-Xian; Li, Jian; Luo, Xin; Xu, Jian-Jun; Shang, Ming-Sheng

2018-02-01

Recommender systems aim to predict people's preferences for online items by analyzing their historical behaviors. A recommender can be modeled as a high-dimensional and sparse bipartite network, where the key issue is to understand the relation between the network structure and a recommender's performance. To address this issue, we choose three network characteristics, clustering coefficient, network density and user-item ratio, as the analyzing targets. For the cluster coefficient, we adopt the Degree-preserving rewiring algorithm to obtain a series of bipartite network with varying cluster coefficient, while the degree of user and item keep unchanged. Furthermore, five state-of-the-art recommenders are applied on two real datasets. The performances of recommenders are measured by both numerical and physical metrics. These results show that a recommender's performance is positively related to the clustering coefficient of a bipartite network. Meanwhile, higher density of a bipartite network can provide more accurate but less diverse or novel recommendations. Furthermore, the user-item ratio is positively correlated with the accuracy metrics but negatively correlated with the diverse and novel metrics.

Auxiliary basis expansions for large-scale electronic structure calculations.

PubMed

Jung, Yousung; Sodt, Alex; Gill, Peter M W; Head-Gordon, Martin

2005-05-10

One way to reduce the computational cost of electronic structure calculations is to use auxiliary basis expansions to approximate four-center integrals in terms of two- and three-center integrals, usually by using the variationally optimum Coulomb metric to determine the expansion coefficients. However, the long-range decay behavior of the auxiliary basis expansion coefficients has not been characterized. We find that this decay can be surprisingly slow. Numerical experiments on linear alkanes and a toy model both show that the decay can be as slow as 1/r in the distance between the auxiliary function and the fitted charge distribution. The Coulomb metric fitting equations also involve divergent matrix elements for extended systems treated with periodic boundary conditions. An attenuated Coulomb metric that is short-range can eliminate these oddities without substantially degrading calculated relative energies. The sparsity of the fit coefficients is assessed on simple hydrocarbon molecules and shows quite early onset of linear growth in the number of significant coefficients with system size using the attenuated Coulomb metric. Hence it is possible to design linear scaling auxiliary basis methods without additional approximations to treat large systems.

Theory and Experiment of Binary Diffusion Coefficient of n-Alkanes in Dilute Gases.

PubMed

Liu, Changran; McGivern, W Sean; Manion, Jeffrey A; Wang, Hai

2016-10-10

Binary diffusion coefficients were measured for n-pentane, n-hexane, and n-octane in helium and of n-pentane in nitrogen over the temperature range of 300 to 600 K, using reversed-flow gas chromatography. A generalized, analytical theory is proposed for the binary diffusion coefficients of long-chain molecules in simple diluent gases, taking advantage of a recently developed gas-kinetic theory of the transport properties of nanoslender bodies in dilute free-molecular flows. The theory addresses the long-standing question about the applicability of the Chapman-Enskog theory in describing the transport properties of nonspherical molecular structures, or equivalently, the use of isotropic potentials of interaction for a roughly cylindrical molecular structure such as large normal alkanes. An approximate potential energy function is proposed for the intermolecular interaction of long-chain n-alkane with typical bath gases. Using this potential and the analytical theory for nanoslender bodies, we show that the diffusion coefficients of n-alkanes in typical bath gases can be treated by the resulting analytical model accurately, especially for compounds larger than n-butane.

Liquid-Infused Smooth Surface for Improved Condensation Heat Transfer.

PubMed

Tsuchiya, Hirotaka; Tenjimbayashi, Mizuki; Moriya, Takeo; Yoshikawa, Ryohei; Sasaki, Kaichi; Togasawa, Ryo; Yamazaki, Taku; Manabe, Kengo; Shiratori, Seimei

2017-09-12

Control of vapor condensation properties is a promising approach to manage a crucial part of energy infrastructure conditions. Heat transfer by vapor condensation on superhydrophobic coatings has garnered attention, because dropwise condensation on superhydrophobic surfaces with rough structures leads to favorable heat-transfer performance. However, pinned condensed water droplets within the rough structure and a high thermodynamic energy barrier for nucleation of superhydrophobic surfaces limit their heat-transfer increase. Recently, slippery liquid-infused surfaces (SLIPS) have been investigated, because of their high water sliding ability and surface smoothness originating from the liquid layer. However, even on SLIPS, condensed water droplets are eventually pinned to degrade their heat-transfer properties after extended use, because the rough base layer is exposed as infused liquid is lost. Herein, we report a liquid-infused smooth surface named "SPLASH" (surface with π electron interaction liquid adsorption, smoothness, and hydrophobicity) to overcome the problems derived from the rough structures in previous approaches to obtain stable, high heat-transfer performance. The SPLASH displayed a maximum condensation heat-transfer coefficient that was 175% higher than that of an uncoated substrate. The SPLASH also showed higher heat-transfer performance and more stable dropwise condensation than superhydrophobic surfaces and SLIPS from the viewpoints of condensed water droplet mobility and the thermodynamic energy barrier for nucleation. The effects of liquid-infused surface roughness and liquid viscosity on condensation heat transfer were investigated to compare heat-transfer performance. This research will aid industrial applications using vapor condensation.

Changes and Trends in the Pallet Industry: Alternative Materials and Industry Structure

Treesearch

Robert J. Bush; Philip A. Araman

1998-01-01

In the first article of this three-part series we described trends in the use of new wood materials for pallets and containers. The second article described changes in pallet recovery and recycling. In this third article, we describe alternative (i.e., other than solid wood) materials used to manufacture pallets as well as changes in the structure of the industry....

[Establishment of industry promotion technology system in Chinese medicine secondary exploitation based on "component structure theory"].

PubMed

Cheng, Xu-Dong; Feng, Liang; Zhang, Ming-Hua; Gu, Jun-Fei; Jia, Xiao-Bin

2014-10-01

The purpose of the secondary exploitation of Chinese medicine is to improve the quality of Chinese medicine products, enhance core competitiveness, for better use in clinical practice, and more effectively solve the patient suffering. Herbs, extraction, separation, refreshing, preparation and quality control are all involved in the industry promotion of Chinese medicine secondary exploitation of industrial production. The Chinese medicine quality improvement and industry promotion could be realized with the whole process of process optimization, quality control, overall processes improvement. Based on the "component structure theory", "multi-dimensional structure & process dynamic quality control system" and systematic and holistic character of Chinese medicine, impacts of whole process were discussed. Technology systems of Chinese medicine industry promotion was built to provide theoretical basis for improving the quality and efficacy of the secondary development of traditional Chinese medicine products.

Pilot-scale biopesticide production by Bacillus thuringiensis subsp. kurstaki using starch industry wastewater as raw material.

PubMed

Ndao, Adama; Sellamuthu, Balasubramanian; Gnepe, Jean R; Tyagi, Rajeshwar D; Valero, Jose R

2017-09-02

Pilot-scale Bacillus thuringiensis based biopesticide production (2000 L bioreactor) was conducted using starch industry wastewater (SIW) as a raw material using optimized operational parameters obtained in 15 L and 150 L fermenters. In pilot scale fermentation process the oxygen transfer rate is a major limiting factor for high product yield. Thus, the volumetric mass transfer coefficient (K L a) remains a tool to determine the oxygen transfer capacity [oxygen utilization rate (OUR) and oxygen transfer rate (OTR)] to obtain better bacterial growth rate and entomotoxicity in new bioreactor process optimization and scale-up. This study results demonstrated that the oxygen transfer rate in 2000 L bioreactor was better than 15 L and 150 L fermenters. The better oxygen transfer in 2000 L bioreactor augmented the bacterial growth [total cell (TC) and viable spore count (SC)] and delta-endotoxin yield. Prepared a stable biopesticide formulation for field use and its entomotoxicity was also evaluated. This study result corroborates the feasibility of industrial scale operation of biopesticide production using starch industry wastewater as raw material.

A study on validating KinectV2 in comparison of Vicon system as a motion capture system for using in Health Engineering in industry

NASA Astrophysics Data System (ADS)

Jebeli, Mahvash; Bilesan, Alireza; Arshi, Ahmadreza

2017-06-01

The currently available commercial motion capture systems are constrained by space requirement and thus pose difficulties when used in developing kinematic description of human movements within the existing manufacturing and production cells. The Kinect sensor does not share similar limitations but it is not as accurate. The proposition made in this article is to adopt the Kinect sensor in to facilitate implementation of Health Engineering concepts to industrial environments. This article is an evaluation of the Kinect sensor accuracy when providing three dimensional kinematic data. The sensor is thus utilized to assist in modeling and simulation of worker performance within an industrial cell. For this purpose, Kinect 3D data was compared to that of Vicon motion capture system in a gait analysis laboratory. Results indicated that the Kinect sensor exhibited a coefficient of determination of 0.9996 on the depth axis and 0.9849 along the horizontal axis and 0.2767 on vertical axis. The results prove the competency of the Kinect sensor to be used in the industrial environments.

Low-Cost Ultrasonic Distance Sensor Arrays with Networked Error Correction

PubMed Central

Dai, Hongjun; Zhao, Shulin; Jia, Zhiping; Chen, Tianzhou

2013-01-01

Distance has been one of the basic factors in manufacturing and control fields, and ultrasonic distance sensors have been widely used as a low-cost measuring tool. However, the propagation of ultrasonic waves is greatly affected by environmental factors such as temperature, humidity and atmospheric pressure. In order to solve the problem of inaccurate measurement, which is significant within industry, this paper presents a novel ultrasonic distance sensor model using networked error correction (NEC) trained on experimental data. This is more accurate than other existing approaches because it uses information from indirect association with neighboring sensors, which has not been considered before. The NEC technique, focusing on optimization of the relationship of the topological structure of sensor arrays, is implemented for the compensation of erroneous measurements caused by the environment. We apply the maximum likelihood method to determine the optimal fusion data set and use a neighbor discovery algorithm to identify neighbor nodes at the top speed. Furthermore, we adopt the NEC optimization algorithm, which takes full advantage of the correlation coefficients for neighbor sensors. The experimental results demonstrate that the ranging errors of the NEC system are within 2.20%; furthermore, the mean absolute percentage error is reduced to 0.01% after three iterations of this method, which means that the proposed method performs extremely well. The optimized method of distance measurement we propose, with the capability of NEC, would bring a significant advantage for intelligent industrial automation. PMID:24013491

Measurement of effective piezoelectric coefficients of PZT thin films for energy harvesting application with interdigitated electrodes.

PubMed

Chidambaram, Nachiappan; Mazzalai, Andrea; Muralt, Paul

2012-08-01

Interdigitated electrode (IDE) systems with lead zirconate titanate (PZT) thin films play an increasingly important role for two reasons: first, such a configuration generates higher voltages than parallel plate capacitor-type electrode (PPE) structures, and second, the application of an electric field leads to a compressive stress component in addition to the overall stress state, unlike a PPE structure, which results in tensile stress component. Because ceramics tend to crack at relatively moderate tensile stresses, this means that IDEs have a lower risk of cracking than PPEs. For these reasons, IDE systems are ideal for energy harvesting of vibration energy, and for actuators. Systematic investigations of PZT films with IDE systems have not yet been undertaken. In this work, we present results on the evaluation of the in-plane piezoelectric coefficients with IDE systems. Additionally, we also propose a simple and measurable figure of merit (FOM) to analyze and evaluate the relevant piezoelectric parameter for harvesting efficiency without the need to fabricate the energy harvesting device. Idealized effective coefficients e(IDE) and h(IDE) are derived, showing its composite nature with about one-third contribution of the transverse effect, and about two-thirds contribution of the longitudinal effect in the case of a PZT film deposited on a (100)-oriented silicon wafer with the in-plane electric field along one of the <011> Si directions. Randomly oriented 1-μm-thick PZT 53/47 film deposited by a sol-gel technique, was evaluated and yielded an effective coefficient e(IDE) of 15 C·m(-2). Our FOM is the product between effective e and h coefficient representing twice the electrical energy density stored in the piezoelectric film per unit strain deformation (both for IDE and PPE systems). Assuming homogeneous fields between the fingers, and neglecting the contribution from below the electrode fingers, the FOM for IDE structures with larger electrode gap is derived to be twice as large as for PPE structures, for PZT-5H properties. The experiments yielded an FOM of the IDE structures of 1.25 × 10(10) J/m(3) and 14 mV/μ strain.

Industrialized timber structures.

DOT National Transportation Integrated Search

1974-01-01

It was recently learned that a number of innovations in structural timber components are available to the construction industry, but that they were largely unknown to bridge designers. The purpose of this study was to develop for the Department a fea...

Determinants of Iran’s Bilateral Intra-industry Trade in Pharmaceutical Industry

PubMed Central

Aghlmand, Siamak; Rahimi, Bahlol; Farrokh-Eslamlou, Hamidreza; Nabilou, Bahram; Yusefzadeh, Hassan

2018-01-01

Among non-oil and in trade arena, drug has always been strategic importance and most government especially industrialized countries pay special attention to its production and trade issues. Thus, having a comprehensive view from economic perspective to this section is essential for suggesting intervention. This was a descriptive-analytical and panel study. In this study, gravity model is used to estimate Iran’s bilateral intra-industry trade in pharmaceutical products in the 2001-2012 periods. To illustrate the extent of pharmaceutical’s intra-industry trade between Iran and its major trading partners, the explanatory variables of market size, income, factor endowments, distance, cultural contributions, and similarities and also special trade arrangements have been applied. Analysis of factors affecting Iran’s bilateral intra-industry trade in pharmaceutical industry showed that the average GDP and cultural similarities had a significant positive impact on Iran’s bilateral IIT, while the difference in GDP has a negative and significant effect. Coefficients obtained for the geographical distance and the average ratio of total capital to the labor force is not consistent with theoretical expectations. Special trade arrangements did not have significant impact on the extent of bilateral intra-industry trade between Iran and its trading partners. The knowledge of the intra-industry trade between Iran and its trade partners make integration between the countries. Factors affecting this type of trade pattern underlie its development in trade relationship. Therefore, the findings of this study would be useful in helping to develop and implement policies for the expansion of the pharmaceutical trade. PMID:29881438

Problems in estimating self-supplied industrial water use by indirect methods, the California example

USGS Publications Warehouse

Burt, R.J.

1983-01-01

Consumptive fresh-water use by industry in California is estimated at about 230 million gallons per day, or about one-half of one percent of agricultural withdrawals in the State , and only about 1 percent of agricultural consumptive use. Therefore, a significant State-wide realignment of the total water resources could not be made by industrial conservation measures. Nevertheless, considerable latitude for water conservation exists in industry -- fresh water consumed by self-supplied industry amounts to about 40 percent of its withdrawals in California, and only about 10 to 15 percent nationally (not including power-plant use). Furthermore, where firms withdraw and consume less water there is more for others nearby to use. The main question in attempting to estimate self-supplied industrial water use in California by indirect methods was whether accurate estimates of industrial water use could be made from data on surrogates such as production and employment. The answer is apparently not. A fundamental problem was that different data bases produced variable coefficients of water use for similar industries. Much of the potential for error appeared to lie in the water data bases rather than the production or employment data. The apparent reasons are that water-use data are based on responses to questionnaires, which are prone to errors in reporting, and because the data may be aggregated inappropriately for this kind of correlation. Industries within an apparently similar category commonly use different amounts of water, both because of differences in the product and because of differences in production processes even where the end-product is similar. (USGS)