bluuebunny/crossref_metadata_2025 huggingface dataset:
Functional understanding of the versatile protein copper metabolism MURR1 domain 1 (COMMD1) in copper homeostasis
Authors: Fedoseienko Alina , Bartuzi Paulina , van de Sluis Bart
Published: February 2014

Copper is an important cofactor in numerous biological processes in all living organisms. However, excessive copper can be extremely toxic, so it is vital that the copper level within a cell is tightly regulated. The damaging effect of copper is seen in several hereditary forms of copper toxicity in humans and animals. At present, Wilson's disease is the best‐described and best‐studied copper‐storage disorder in humans; it is caused by mutations in the ATP7B gene. In dogs, a mutation in the COMMD1 gene has been found to be associated with copper toxicosis. Using a liver‐specific Commd1 knockout mouse, the biological role of Commd1 in copper homeostasis has been confirmed. Yet, the exact mechanism by which COMMD1 regulates copper homeostasis is still unknown. Here, we give an overview of the current knowledge and perspectives on the molecular function of COMMD1 in copper homeostasis.
MAKING WORK INVISIBLE: NEW PUBLIC MANAGEMENT AND OPERATIONAL WORK IN CRITICAL INFRASTRUCTURE SECTORS
Authors: ALMKLOV PETTER GRYTTEN , ANTONSEN STIAN
Published: February 2014

Based on a study of reliability consequences of New Public Management (NPM) reforms in Norwegian critical infrastructure sectors, this article suggests that the discourse of work found inNPMrenders essential aspects of operational work invisible—including practices that are known to be of importance for reliability. We identify two such organizationally ‘invisible’ characteristics of operational work: the ongoingsituational coordinationrequired for keeping a water supply system or an electricity grid running, and the aggregatingoperational historywithin which this happens. In the reorganized infrastructure sectors, these crucial aspects of operational work fit poorly in market oriented organizational models and control mechanisms. More generally, our analysis contributes to the understanding of how some types of work fit poorly within the discourse of work found inNPM.
Sun‐induced freckling: ephelides and solar lentigines
Authors: Praetorius Christian , Sturm Richard A. , Steingrimsson Eirikur
Published: February 2014

Freckles, the lay term for ephelides and lentigines, are important pigmentation characteristics observed in humans. Both are affected by sunlight; ephelides are largely genetically determined but induced by sunlight, whereas lentigines are induced by sun exposure and photodamage of the skin. However, despite being commonly observed, we know very little about them. Here, we review the current status of knowledge about freckles and propose a model for their formation.
Bilateral Congenital Entropion with Cutis Laxa
Authors: Al‐Faky Yasser H. , Salih Mustafa A. , Mubarak Mohammed , Al‐Rikabi Ammar C.
Published: February 2014

Cutis laxa is a rare connective tissue disorder characterized by redundant and pendulous skin due to a defect in the elastic fiber network. Two cases of entropion associated with cutis laxa have been reported, although entropion was due to elongation of the anterior lamella or horizontal lid laxity. Thorough systemic and ophthalmic evaluations were performed, as well as chart review for the perinatal period. Surgical correction of entropion through posterior tarsotomy was done. An infant boy with dysmorphic features and furrowing of the skin of the entire body without hyperelasticity, which is typical for cutis laxa, presented with bilateral congenital entropion. We report here for the first time a different etiology of congenital entropion with cutis laxa: the eyelashes were abnormally directed due to the unusual location of their roots, which were embedded within the tarsus. Moreover, this is the only case of cutis laxa with congenital entropion involving both upper and lower eyelids. Congenital entropion can be associated with cutis laxa. Although elongation of the anterior lamella and horizontal lid laxity predispose to such an entropion, abnormal location of the roots of the eyelashes might be encountered and marginal eyelid rotation surgery is indicated.
Differential accumulation of γ‐aminobutyric acid in elicited cells of two rice cultivars showing contrasting sensitivity to the blast pathogen
Authors: Forlani G. , Bertazzini M. , Giberti S.
Published: February 2014

Intracellular free amino acid pools were quantified in suspension cultured cells of a blast‐sensitive and a blast‐resistant rice genotype at increasing times after treatment with Magnaporthe oryzae cell wall hydrolysates. Besides some expected variations in free phenylalanine, a remarkable early increase of γ‐aminobutyric acid (GABA) levels was evident in both cultivars. Glutamate decarboxylase activity and protein levels were unaffected. GABA homeostasis was recovered in the sensitive cultivar 48 h after the treatment. In contrast, a further GABA accumulation and a general increase of most amino acids was found at this later stage in the resistant genotype, which showed a larger decrease in cell viability as a consequence of elicitor addition. Data support a recently hypothesised role of GABA metabolism in the plant response to fungal pathogens.
Strong Candidate, Nurturant Candidate: Moral Language in Presidential Television Advertisements
Authors: Moses Jennifer Filson , Gonzales Marti Hope
Published: February 2014

Presidential television advertisements from 1980 through 2012 were examined to test empirically George Lakoff's descriptions of American moral ideology. Advertisements were coded for instantiations of the moral themes that Lakoff asserts underlie liberal and conservative ideology (Strict Father versus Nurturant Parent). Candidates' political‐party affiliation, election year, and policy issue(s) addressed in the television advertisement were assessed for their covariance with the use of these moral‐metaphorical instantiations. Findings support many of Lakoff's arguments. Republicans and Democrats generally differed in their use of these moral themes, both Strict Father and Nurturant Parent. There were no significant associations between election years (1980–2012) and instantiations of moral metaphors, with the exception of 2008, an anomalous year. Of particular import, we found that although Republicans rely on Strict Father dimensions, and Democrats rely more on Nurturant Parent, the most pronounced difference between parties was on the Nurturant Parent dimension. Implications for Lakoff's work and current moral psychology are discussed.
The Sins of Their Fathers: When Current Generations Are Held to Account for the Transgressions of Previous Generations
Authors: Goto Nobuhiko , Jetten Jolanda , Karasawa Minoru , Hornsey Matthew J.
Published: February 2014

When are current generations held accountable for transgressions committed by previous generations? In two studies, we test the prediction that current generations will only be assigned guilt for past atrocities when victim group members perceive high levels of cultural continuity between historical perpetrators and the current generation within the perpetrator group. Japanese participants were presented with information describing the current generation of Americans as either similar or dissimilar in personality to the Americans who were implicated in dropping the atomic bomb on Japan during World War II. The results of both studies revealed that victim group members assigned more guilt to current Americans when they perceived high (compared to low) outgroup continuity, and they did so relatively independently of the transgressor group's guilt expressions.
Dynamic changes in plant secondary metabolites during UV acclimation in Arabidopsis thaliana
Authors: Hectors Kathleen , Van Oevelen Sandra , Geuns Jan , Guisez Yves , Jansen Marcel A. K. , Prinsen Els
Published: February 2014

Plants respond to environmental stress by synthesizing a range of secondary metabolites for defense purposes. Here we report on the effect of chronic ultraviolet (UV) radiation on the accumulation of plant secondary metabolites in Arabidopsis thaliana leaves. In the natural environment, UV is a highly dynamic environmental parameter and therefore we hypothesized that plants are continuously readjusting levels of secondary metabolites. Our data show distinct kinetic profiles for accumulation of tocopherols, polyamines and flavonoids upon UV acclimation. The lipid‐soluble antioxidant α‐tocopherol accumulated fast and remained elevated. Polyamines accumulated fast and transiently. This fast response implies a role for α‐tocopherol and polyamines in short‐term UV response. In contrast, an additional sustained accumulation of flavonols took place. The distinct accumulation patterns of these secondary metabolites confirm that the UV acclimation process is a dynamic process, and indicates that commonly used single time‐point analyses do not reveal the full extent of UV acclimation. We demonstrate that UV stimulates the accumulation of specific flavonol glycosides, i.e. kaempferol and (to a lesser extent) quercetin di‐ and triglycosides, all specifically rhamnosylated at position seven. All metabolites were identified by Ultra Performance Liquid Chromatography (UPLC)‐coupled tandem mass spectrometry. Some of these flavonol glycosides reached steady‐state levels in 3–4 days, while concentrations of others are still increasing after 12 days of UV exposure. A biochemical pathway for these glycosides is postulated involving 7‐O‐rhamnosylation for the synthesis of all eight metabolites identified. We postulate that this 7‐O‐rhamnosylation has an important function in UV acclimation.
Crowdsourcing and regulatory reviews: A new way of challenging red tape in British government?
Authors: Lodge Martin , Wegrich Kai
Published: February 2014

Much has been said about the appeal of digital government devices to enhance consultation on rulemaking. This paper explores the most ambitious attempt by the UK central government so far to draw on “crowdsourcing” to consult and act on regulatory reform, the “Red Tape Challenge.” We find that the results of this exercise do not represent any major change to traditional challenges to consultation processes. Instead, we suggest that the extensive institutional arrangements for crowdsourcing were hardly significant in informing actual policy responses: neither the tone of the crowdsourced comments, the direction of the majority views, nor specific comments were seen to matter. Instead, it was processes within the executive that shaped the overall governmental responses to this initiative. The findings, therefore, provoke wider debates about the use of social media in rulemaking and consultation exercises.
Xenon ventilation computed tomography and the management of asthma in the elderly
Authors: Park Heung‐Woo , Jung Jae‐Woo , Kim Kyung‐Mook , Kim Tae‐Wan , Lee So‐Hee , Lee Chang Hyun , Goo Jin Mo , Min Kyung‐Up , Cho Sang‐Heon
Published: February 2014

Background and objective

Xenon ventilation computed tomography (CT) has shown potential in assessing the regional ventilation status in subjects with asthma. The purpose of this study was to evaluate the usefulness of xenon ventilation CT in the management of asthma in the elderly.

Methods

Treatment‐naïve asthmatics aged 65 years or older were recruited. Before initiation of medication, spirometry with bronchodilator (BD) reversibility, questionnaires to assess the severity of symptoms including a visual analogue scale (VAS), tests to evaluate cognitive function and mood, and xenon ventilation CT were performed. Xenon gas trapping (XT) on xenon ventilation CT represents an area where inhaled xenon gas was not expired and was trapped. Symptoms and lung functions were measured again after the 12‐week treatment.

Results

A total of 30 elderly asthmatics were enrolled. The severity of dyspnoea measured by the VAS showed a significant correlation with the total number of areas of XT on the xenon ventilation CT taken in the pre‐BD wash‐out phase (r = −0.723, P < 0.001). The total number of areas of XT significantly decreased after BD inhalation, and differences in the total number of areas of XT (between the pre‐ and post‐BD wash‐out phases) at baseline showed significant correlations with the per cent increases in forced expiratory volume in 1 s after subsequent anti‐asthma treatment (r = −0.775, P < 0.001).

Conclusions

Xenon ventilation CT may be an objective and promising tool in the measurement of dyspnoea and prediction of the treatment response in elderly asthmatics.
Neogene upper‐crustal cooling of the Olympus range (northern Aegean): major role of Hellenic back‐arc extension over propagation of the North Anatolia Fault Zone
Authors: Coutand Isabelle , Walsh Michael , Louis Bertha , Chanier Frank , Ferrière Jacky , Reynaud Jean‐Yves
Published: February 2014

The North Anatolian Fault Zone (NAFZ) is one of the most hazardous active faults on Earth, yet its Pliocene space‐time propagation across the north Aegean domain remains poorly constrained. We use low‐temperature multi‐thermochronology and inverse thermal modelling to quantify the cooling history of the upper crust across the Olympus range. This range is located in the footwall of a system of normal faults traditionally interpreted as resulting from superposed Middle–Late Miocene N–S stretching, related to the back‐arc extension of the Hellenic subduction zone, and a Pliocene‐Quaternary transtensional field, attributed to the south‐westward propagation of the NAFZ. We find that accelerated exhumational cooling occurred between 12 and 6 Ma at rates of 15–35 °C Ma−1 and decreased to <3 °C Ma−1 by 8–6 Ma. The absence of significant Plio‐Pleistocene cooling across Olympus suggests that crustal exhumation there is driven by late Miocene back‐arc extension, while the impact of the NAFZ remains limited.
Vector competence of Culex pipiens quinquefasciatus (Diptera: Culicidae) for West Nile virus isolates from Florida
Authors: Richards Stephanie L. , Anderson Sheri L. , Lord Cynthia C.
Published: February 2014

Objectives

To assess vector competence (infection, dissemination and transmission) of Culex pipiens quinquefasciatus for Florida (FL) West Nile virus (WNV) isolates.

Methods

West Nile virus isolates (WN‐FL‐03: NY99 genotype; WN‐FL‐05‐558, WN‐FL‐05‐2186, WN‐FL‐05‐510: WN02 genotype) collected from different regions of FL were used for vector competence experiments in Cx. p. quinquefasciatus from Alachua County and Indian River County in FL. Mosquitoes from both colonies were fed blood containing 7.9 ± 0.2 log10 plaque‐forming units WNV/ml ± SE and incubated at 28 °C for 14 days. Vector competence, including rates of infection, dissemination, and transmission, was compared between colonies for WN‐FL‐03 using chi‐squared. Virus titres in bodies, legs and saliva were compared using anova. Daily measurements of in vitro replication of WNV isolates were evaluated in Vero cells so that a standardised virus dose for each isolate could be delivered to mosquitoes.

Results

Infection and dissemination rates were high (≥95%) and not affected by isolate or colony (infection, P = 0.679; dissemination, P = 0.799). Transmission rates were low (≤20%), detected in one colony and affected by isolate (P = 0.008). Body and leg titres differed between isolates (body titre, P = 0.031; leg titre, P = 0.044) and colonies (body titre, P = 0.001; leg titre, P = 0.013) while saliva titre did not differ between isolates (P = 0.462).

Conclusions

Variation in vector competence of mosquito populations may be attributed, in part, to exposures to WNV with genetic differences leading to different rates of replication in mosquitoes. Evaluation of vector competence for different WNV isolates may help us understand vector–virus interactions and, hence, the role of vectors in complex virus transmission cycles in nature.
Strategic Trade Policy through the Tax System
Authors: Becker Johannes
Published: February 2014

If conventional instruments of strategic trade policy are unavailable, the system of foreign profit taxation and transfer price guidelines may serve as surrogate policy instruments. In this paper, I consider a model where firms from two countries compete with each other on a market in a third country. Both firms have affiliates in the third country where (part of) the production takes place. I analyse optimal policy choices of the firms' residence countries aiming at strategically manipulating the competitiveness of their firms. I show that, first, countries prefer the tax exemption system over the tax credit system if there is no intra‐firm trade. Second, if the headquarters provide inputs for production in the affiliate, countries prefer the tax exemption system if the transfer price for these inputs is close to the headquarters' variable cost and if the residence country's tax rate is high. However, if transfer prices are high and the residence country's tax rate is low, I show that the tax credit system is an optimal tax policy choice for both countries. From a policy perspective, the view that the tax exemption system is generally the best policy response if domestic firms' competitiveness is a policy goal has to be qualified.
Changes in hematology measurements in healthy and diseased dog blood stored at room temperature for 24 and 48 hours using theXT‐2000iV analyzer
Authors: Bourgès‐Abella Nathalie H. , Geffré Anne , Deshuillers Pierre L. , Braun Jean‐Pierre D. , Trumel Catherine
Published: February 2014

Background

Changes in canine hematology measurements may occur when analyses are delayed due to shipment of specimens to a laboratory.

Objective

The purpose of this study was to report changes in hematologic variables in healthy and diseased canine blood measured with a SysmexXT‐2000iV during storage at room temperature for 24 and 48 hours.

Methods

EDTA‐K3 blood samples from 42 healthy and diseased dogs were measured on a SysmexXT‐2000iV analyzer within one hour of sampling, and after storage for 24 and 48 hours at room temperature in the dark.

Results

Storage caused little or no change inRBCcount,HGBconcentration andMCH, while there was a moderate increase inHCT,MCVand reticulocytes count, and a moderate decrease inMCHC. Decreased platelet counts by impedance (PLT‐I) and optical (PLT‐O) measurements were associated with increased mean platelet volume (MPV), platelet‐large cell ratio (P‐LCR) and platelet distribution width (PDW), including a right shift in the platelet histogram and a dispersion of the platelet dot plot on the scattergram. The total and differentialWBCcount remained stable except for decreased monocyte counts. In the scatterplots, monocytes shifted into the lymphocyte population after 24 hours, and neutrophil population shifted to the right appearing in the eosinophil gate at 48 hours of storage. The disease status had only a small effect on storage‐induced changes, and observed changes had no consequences for clinical decisions.

Conclusions

Blood storage at room temperature was accompanied by moderate variations in some hematologic variables, awareness of which helps in avoiding misinterpretations.
Management of bleeding in severe factor V deficiency with a factor V inhibitor
Authors: Ardillon L. , Lefrançois A. , Graveleau J. , Fouassier M. , Ternisien C. , Sigaud M. , Fretigny M. , Archambeaud I. , Trossaërt M.
Published: February 2014

Factor V (FV) inhibitor arises rarely after using fresh frozen plasma (FFP) to treat inherited FV deficiency and is often a real therapeutic challenge. Here, we report a patient with a severe FV deficiency who developed such an inhibitor and was then treated with recombinant activated FVII (rFVIIa) and platelet concentrates (PC). Monitoring was assessed by thrombin generation assay (TGA). PC were more effective than rFVIIa in treating bleeding, but there was no correlation between the TGA results and clinical efficacy.
Computational Investigation of Air-Heater Performance Using Natural Gas, Biogas, and Syngas as Fuels
Authors: Diaz Gerardo
Published: February 2014

Alternative fuels, mainly generated from waste, constitute a possible option to reduce the demand for fossil fuels. For instance, biogas can be obtained from cow manure using anaerobic digesters, a technology that is currently being implemented in several dairy farms. Synthesis gas, also known as syngas, is a mixture of hydrogen and carbon monoxide that may have fractions of other components such as nitrogen, carbon dioxide, and methane, depending on the gasifying method used. However, before a change to alternative fuels can be made, the performance of common appliances and industrial equipment using these fuels needs to be investigated. In this paper, a computational analysis of the performance of an air heater using natural gas, biogas, and syngas is performed. The results show that alternative fuels with heat values almost an order of magnitude lower than natural gas can be used in commercial air heaters with only minor variations in thermal performance. The main drawback is the higher flow rates required for alternative fuels, specially for syngas.
An Experimental Investigation of an Oscillating Heat Pipe Heat Spreader
Authors: Laun F. F. , Lu H. , Ma H. B.
Published: February 2014

With ever increasing technological advances in electronics, modern computer components continue to produce higher power densities that present a challenge to thermal management. A radial flat-plate oscillating heat pipe (RFP-OHP) heat spreader is investigated to study the effect of central heating on the heat transport capability in an OHP. The investigated OHP has dimensions of 100 mm × 100 mm × 2.5 mm with central heating using a 30 mm × 30 mm heater. Experimental results show that when heat is added to the center section of one side of the radial flat-plate OHP, and when heat is removed from the whole surface of another side of the heat pipe, the startup power for the oscillating motion increases. In addition, the spacer effect on the heat transport capability including the startup is investigated experimentally. The spacer added between the cooling block and OHP could lower the startup power for oscillatory motion. When compared to a copper slab of the same dimensions in the same test configuration, the temperature difference for the OHP with and without the additional copper spacer was reduced by a maximum of 46% and 25%, respectively, at a power input of 525 W and a heat flux of 58 W/cm2.
A Phenomenological Model for Fatigue Crack Growth Rate of X70 Pipeline Steel in H2S Corrosive Environment
Authors: Wang Jing , Li Xiao-yang
Published: February 2014

Long distance pipeline transmission is considered to be the most economic and safest method to transport natural gas in recent days. The pipeline safety problem is a focus of concern in the academic and industrial circles. Wildly used material X70 pipeline steel is tested in this paper. Based on actual conditions of long distance pipeline, experiments were designed by using orthogonal method. Corrosion fatigue crack growth tests were carried out under different H2S concentrations (2000 ppm, 1000 ppm, 500 ppm), stress ratios (0.9, 0.8, 0.7), and load frequencies (0.0067 Hz, 0.01 Hz, 0.013 Hz). A phenomenological model was built based on test data and Paris formula, which corrects parameters C and n of the Paris formula at the same time. The boundary element method (BEM) was used to simulate the process of corrosion fatigue crack propagation. Fatigue crack growth rates (FCGRs) under different loading conditions were obtained and all the parameters of the phenomenological model were calculated from test data. Compared with traditional Paris formula, this new model shows coupling interactions of stress ratio, load frequency, and H2S concentration to both slope and intercept of FCGR curve in log-log space. The simulation results show that the largest difference between actual test data and BEM simulation is less than 10%. According to the analysis of coupling interactions of each factor, the slope of fatigue crack growth rate (FCGR) curve in log-log space is mainly influenced by frequency; the influence of H2S concentration is nonlinear, and FCGR increases significantly with the increase of stress ratio and decrease of frequency. The BEM is suitable to be used in the engineering field to predict the residual life of pipelines.
Construction of a Carbon Fiber Reinforced Weft Guide Bar for a Crochet Knitting Machine
Authors: Beer Mathias , Gloy Yves-Simon , Raina Mohit , Gries Thomas
Published: February 2014

The crochet knitting machine is a warp knitting machine with a weft insertion system placed on a weft guide bar. On standard machines, the weft guide bar is made from aluminum and weighs about 570 g. The single-drive motors, which power the bar, account for 15–20% of the machines total power consumption. The aim of this research was to reduce power consumption by decreasing the mass of the weft guide bar. This was done by constructing the bar from carbon fiber reinforced plastics rather than aluminum, resulting in a mass saving of 260 g.
Manufacture of Arbitrary Cross-Section Composite Honeycomb Cores Based on Origami Techniques
Authors: Saito Kazuya , Pellegrino Sergio , Nojima Taketoshi
Published: February 2014

As observed in the design of antenna reflectors and rocket bodies, both flat and 3D-shaped honeycomb cores are used in the field of aerospace engineering. This study illustrates a new strategy to fabricate arbitrary cross-section honeycombs with applications of advanced composite materials by using the concept of the kirigami honeycomb, which is made from single flat sheets and has periodical slits resembling origami. The authors also describe a method of applying this technique to advanced composite materials. Applying the partially soft composite techniques, 3D shaped composite honeycombs are manufactured, and some typical samples are shown with their folding line diagrams.
Evaluating the Directed Intuitive Approach for Bioinspired Design
Authors: Glier Michael W. , Tsenn Joanna , Linsey Julie S. , McAdams Daniel A.
Published: February 2014

Bioinspired design, the practice of looking to nature to find inspiration for solutions to engineering problems, is increasingly a desired approach to design. It allows designers to tap a wealth of time-tested solutions to difficult problems in a domain less considered by designers. Only recently have researchers developed organized, systematic methods for bioinspired design. Traditionally, bioinspired design has been conducted without the benefit of any organized method. Designers relied on the informal “directed intuitive approach” of bioinspired design, which simply directs designers to consider how nature might solve a problem. This paper presents an experiment to explore the impact of the directed approach on idea generation. This experiment is foundationally important to bioinspired engineering design method research. The results of this experiment serve as a fundamental baseline and benchmark for the comparison of more systematic, and often more involved, bioinspired design methods. A group of 121 novice designers are given one of two design problems and instructed to either generate solutions using the directed approach or to generate solutions without being prompted in any additional fashion. Based on the findings presented here, the directed approach offers designers no advantage in the average number of nonredundant ideas, quality, novelty, or variety of the solutions produced. In conclusion, systematic and organized methods for bioinspired design should be sought to effectively leverage nature's design knowledge.
Structural Manipulation of Microcone Arrays for Microsurgical Modification of Ophthalmic Tissues
Authors: Wing B. J. , Schaeffer D. A. , Hendricks T. R. , Bennett D. , Chaum E. , Simpson J. T.
Published: February 2014

The purpose of this study was to utilize controllable fiber-drawing techniques in order to fabricate glass microcone arrays for use in office-based optical surgery instruments. The cone spacing is controlled via the drawing process while an etching process controls the cone height-to-base ratio. The device viability was tested by imprinting, and subsequent staining, of low-density polyethylene and porcine corneas, resulting in a consistent patterned structure of micron-sized perforations. After imprint, the device was examined and no evidence of microcone fracture or overpenetration was present during the course of these experiments. This research promises to lead to advances in optical surgery for the treatment of recurrent corneal erosions, providing quicker, safer, and more cost-effective procedures with decreased risk of vision loss and scarring associated with current procedures such as anterior stromal puncture. The ease of procedure and micron-sized incisions could potentially replace current techniques and provide a viable treatment alternative for recurrent corneal erosions in the visual axis.
Structural Complexity Quantification for Engineered Complex Systems and Implications on System Architecture and Design
Authors: Sinha Kaushik , de Weck Olivier L.
Published: February 2014

The complexity of today’s highly engineered products is rooted in the interwoven architecture defined by its components and their interactions. Such structures can be viewed as the adjacency matrix of the associated dependency network representing the product architecture. To evaluate a complex system or to compare it to other systems, numerical assessment of its structural complexity is essential. In this paper, we develop a quantitative measure for structural complexity and apply the same to real-world engineered systems like gas turbine engines. It is observed that low topological complexity implies centralized architectures and that higher levels of complexity generally indicate highly distributed architectures. We posit that the development cost varies non-linearly with structural complexity. Empirical evidence of such behavior is presented from the literature and preliminary results from simple experiments involving assembly of simple structures further strengthens our hypothesis. We demonstrate that structural complexity and modularity are not necessarily negatively correlated using a simple example. We further discuss distribution of complexity across the system architecture and its strategic implications for system development efforts.
Outlining Nine Major Design Challenges of Open, Decentralized, Adaptive Cyber-Physical Systems
Authors: Horváth Imre , Gerritsen Bart H. M.
Published: February 2014

Open, decentralized, adaptive cyber-physical systems (ODA-CPSs) have countless novel structural attributes and functional affordances. Consequently, they pose many design and engineering challenges. This paper identifies and analyzes nine of them. They are: (i) handling aggregative complexity, (ii) establishing static and dynamic compositional synergy, (iii) managing dynamic and evolutionary operation in time, (iv) multi-abstraction-based modeling, (v) system integrity verification and behavior validation, (vi) achieving dynamic scalability towards meta-systems, (vii) transformation of big data, (viii) employing testable surrogate prototyping, and (ix) attaining robust social compliance. These challenges should be addressed already in the course of conceptualization and design of these systems. It is shown that a kind of duality is hiding practically in each of these challenges, which are caused by the concurrence of short term dynamic behavior and long term evolution of ODA-CPSs. Though interrelated, these two aspects still need to be handled separate. In order to response effectively to the above challenges, foundational research and operative research need to produce new transdisciplinary insights and new practical principles, respectively. First, previous efforts in these dimensions are critically evaluated. Then it is circumscribed what new knowledge is needed in order to cope with the considered major challenges. Putting everything together, the paper concludes that the grand challenge is in the lack of a dedicated transdisciplinary design theory that could explain how ODA-CPSs should be ideated and synthesized, and that would allow the development of a comprehensive design methodology and computational support tools. Future research will attempt to propose concrete solutions for the discussed challenges and most probably identify other emerging ones.
Planar Linkage Synthesis for Rigid Body Guidance Using Poles and Rotation Angles
Authors: Zimmerman Ronald A.
Published: February 2014

A graphical four bar linkage synthesis method for planar rigid body guidance is presented. This method, capable of synthesis for up to five specified coupler positions, uses the poles and rotation angles, which are constraints, to define guiding links. Faster and simpler than traditional graphical synthesis methods, this method, allows the designer to see and consider most or all the possible solutions within a few seconds before making any free choices. All of the guiding links satisfying five specified coupler positions can be obtained graphically within 30 minutes without plotting any Burmester curves and without any mechanism design software. For four positions, both the circle and center point curves are simultaneously traced by corresponding circle-center point pairs using three poles having a common subscript and the corresponding rotation angles without any additional construction. This method eliminates the iterative construction required in previous methods which were based on free choices rather than constraints. The tedious plotting of Burmester curves graphically using pole quadrilaterals is also eliminated. The simplicity of the method makes four and five position synthesis practical to do graphically.

A corresponding analytical solution is presented which provides a simpler formulation than the previous solution method. This new method requires two fewer equations and provides a new way to plot Burmester curves analytically.
Gear Tooth Stresses From Finite Element Analysis Compared With AGMA Standards
Authors: Jammi Srinivasa
Published: February 2014

The gear trains are conventionally designed following AGMA standards developed by using basic Lewis formula with several modifications; these standards are very conservative. The finite element methods provide an accurate assessment of bending and contact stresses and a comparison is made in this paper with AGMA values to understand the over design and safe characteristic of the standards versus FE values.
The Development of a Longitudinal Control System for a Sports-Utility-Vehicle
Authors: Hamersma Herman , Els Schalk
Published: February 2014

A common problem with sports-utility-vehicles is the low rollover threshold, due to a high center of gravity. Instead of modifying the vehicle to increase the rollover threshold, the aim of the control system is to prevent the vehicle from exceeding speeds that would cause the vehicle to reach its rollover threshold. The aim of the autonomous longitudinal control system, discussed here, is to improve the vehicle’s safety by controlling the vehicle’s longitudinal behavior.

In order to develop a control system that autonomously controls the longitudinal degree of freedom, an experimentally validated mathematical model of the test vehicle (a 1997 Land Rover Defender 110 Wagon) was used — the model was developed in MSC.ADAMS/View. The control system was developed by generating a reference speed that the vehicle must track. This reference speed was formulated by taking into account the vehicle’s limits due to lateral acceleration, combined lateral and longitudinal acceleration and the vehicle’s performance capabilities.

The MSC.ADAMS/View model of the test vehicle was used to evaluate the performance of the control system on various racetracks for which the GPS coordinates were available. The simulation results indicate that the control system performed as expected by limiting the vehicle’s acceleration vector to the prescribed limits.
Dynamics of Battery Tabs Under Ultrasonic Welding
Authors: Kang Bongsu , Cai Wayne , Tan Chin-An
Published: February 2014

Ultrasonic metal welding for battery tabs must be performed with 100% reliability in battery pack manufacturing as the failure of a single weld essentially results in a battery that is inoperative or cannot deliver the required power due to the electrical short caused by the failed weld. In ultrasonic metal welding processes, high-frequency ultrasonic energy is used to generate an oscillating shear force (sonotrode force) at the interface between a sonotrode and few metal sheets to produce solid-state bonds between the sheets clamped under a normal force. These forces, which influence the power needed to produce the weld and the weld quality, strongly depend on the mechanical and structural properties of the weld parts and fixtures in addition to various welding process parameters such as weld frequencies and amplitudes. In this work, the effect of structural vibration of the battery tab on the required sonotrode force during ultrasonic welding is studied by applying a longitudinal vibration model for the battery tab. It is found that the sonotrode force is greatly influenced by the kinetic properties, quantified by the equivalent mass and equivalent stiffness, of the battery tab and cell pouch interface. This study provides a fundamental understanding of battery tab dynamics during ultrasonic welding and its effects on weld quality, and thus provides useful guidelines for design and welding of battery tabs from tab dynamics point of view.
An Investigation of the Ward Leonard System for Use in a Hybrid or Electric Passenger Vehicle
Authors: Telford Cody L. , Todd Robert H.
Published: February 2014

Since the early 1900’s demand for fuel efficient vehicles has motivated the development of electric and hybrid electric vehicles. Unfortunately, some components used in these vehicles are expensive and complex. Todays consumer electric vehicles use dangerously high voltage, expensive electronic controllers, complex battery management systems and AC motors. The goal of this research at BYU is to increase safety by lowering the operating voltage and decrease cost by eliminating expensive controllers and decrease the number of battery cells.

This paper specifically examines the use of a Ward Leonard Motor Control system for use in a passenger vehicle. The Ward Leonard System provides an alternative control method to expensive and complex systems used today.

A Control Factor metric was developed as a result of this research to measure the Ward Leonard System’s ability to reduce the size and cost of the electronic controller for application in an EV or HEV. A bench top model of the Ward Leonard system was tested validating the Control Factor metric. The Ward Leonard system is capable of reducing the controller size by 77% and potentially reducing its cost by this amount or more. This work also provides performance characteristics for automotive designers and offers several design alternatives for EV and HEV architectures allowing a reduction in voltage, the use of AC inverters, AC motors, expensive controllers and high cell count battery packs.
Kinematic and Dynamic Analysis of V-Twin Powertrains: Design Trade-Offs
Authors: Kaul Sudhir , Kanakasabai Pugazhendhi
Published: February 2014

This paper examines the influence of multiple design parameters on the kinematics and dynamics of a V-twin powertrain. Two models are presented to study the design trade-offs in order to provide an analytical tool that can be used for the top-level design of a V-twin powertrain. Shaking forces and bearing loads are evaluated to quantitatively comprehend the influence of design parameters such as banking angle, crank pin, piston off-set, etc. Furthermore, the influence of parameters associated with the use of conventional Lanchester balance shafts is also investigated as part of the analysis. These parameters include support bearing locations and balancing mass location on the balance shaft. The analysis results are compared to some of the studies on balancing of shaking forces and shaking moments in the literature. While the design trade-offs associated with parameters such as banking angle are well understood in the available literature, the analysis performed in this study shows interesting results for piston off-set and crank pin design, as well as for parameters associated with the balance shaft.
Optimal Machine Tool Settings for the Manufacture of Face-Hobbed Spiral Bevel Gears
Authors: Simon Vilmos V.
Published: February 2014

In this study, an optimization methodology is proposed to systematically define optimal head-cutter geometry and machine tool settings to simultaneously minimize tooth contact pressures and angular displacement error of the driven gear and to reduce the sensitivity of face-hobbed spiral bevel gears to misalignments, while concurrently confining the loaded contact pattern within the tooth boundaries and avoiding any edge- or corner-contact conditions. The proposed optimization procedure relies heavily on a loaded tooth contact analysis for the prediction of tooth contact pressure distribution and transmission errors influenced by the misalignments inherent in the gear pair. The targeted optimization problem is a nonlinear constrained optimization problem. The core algorithm of the proposed nonlinear programming procedure is based on a direct search method. Effectiveness of this optimization was demonstrated on a face-hobbed spiral bevel gear example. Drastic reductions in the maximum tooth contact pressure (62%) and in the transmission errors (70%) were obtained.
Embedded Multi Core Virtual Prototyping for Software Engineers
Authors: Wenzl Matthias , Schuster Harald , Obermayer Christian , Balog Peter
Published: February 2014

Scalability tests are a common method to verify the adaptability of software components. When developing embedded systems, these tests could be put into practice by increasing the number of computing cores, as well as by changing the underlying processor architecture, for example. Therefore, it is common practice to utilize reconfigurable virtual platforms for embedded software scalability tests and design space exploration. Nevertheless, setting up proper test cases, consisting of distinct virtual platform configurations, toolchains, linker scripts and startup codes requires in-depth knowledge in hardware development. Therefore, in order to offer software engineers the possibility to create and operate a variety of possible virtual heterogeneous embedded multi core platforms for testing purposes on their own, this paper introduces a tool set for creating virtual platforms including appropriate toolchains and build environments from a software engineer’s point of view. The feasibility of our tool set was evaluated in a user-centered case study. Hence, a group of software engineers are asked to perform certain tasks in the field of embedded multi core programming.
Two Paths to Isochronicity in a Class of One Degree of Freedom Oscillators
Authors: Kovacic Ivana N. , Rand Richard H.
Published: February 2014

We propose a class of problems in nonlinear vibrations related to avoiding undesirable hysteresis and jump phenomena by designing an oscillator for which the backbone curve is a straight vertical line. In particular we consider the class of conservative oscillators of the form: x..+xx.2+fx=0 and we choose f(x) so that the frequency of oscillation is independent of amplitude. We do this in two ways:

1) by expanding f(x) in a power series and using a perturbation method to compute the coefficients, and

2) by starting with a simple harmonic oscillator (which has a straight line backbone curve), and choosing a transformation which puts the resulting equation in the above form.

We show that both methods result in a closed form expression for f(x) which involves the imaginary error function erfi(z).
Generalized Polynomial Chaos-Based Extended Kalman Filter: Improvement and Expansion
Authors: Kolansky Jeremy , Sandu Corina
Published: February 2014

The generalized polynomial chaos (gPC) method for propagating uncertain parameters through dynamical systems (previously developed at Virginia Tech) has been shown to be very computationally efficient. This method seems also to be ideal for real-time parameter estimation when merged with the Extended Kalman Filter (EKF). The resulting technique is shown in the present paper for systems in state-space representations, and then expanded to systems in regressions formulations. Due to the way the filter interacts with the polynomial chaos expansions, the covariance matrix is forced to zero in finite time. This problem shows itself as an inability to perform state estimations and causes the parameters to converge to incorrect values for state space systems. In order to address this issue, improvements to the method are implemented and the updated method is applied to both state space and regression systems. The resultant technique shows high accuracy of both state and parameter estimations.
Fault Diagnosis and Prognosis in Rotating Machines Carried Out by Means of Model-Based Methods: A Case Study
Authors: Vania A. , Pennacchi P. , Chatterton S.
Published: February 2014

Diagnostic methods, based on mathematical models, can be used to identify the most common faults and malfunctions of rotating machines by minimizing the error between experimental vibration data and the corresponding theoretical response of the rotor system caused by a specific set of excitations. These techniques allow the severity and location of the fault to be estimated. Moreover, depending on the fault characteristics, model-based prognostic techniques can be used to study appropriate corrective actions that can eliminate the cause of the malfunctions or reduce the machine vibration levels. This paper shows the results of a diagnostic analysis carried out to investigate the cause of the high vibration of the HP-IP steam turbine of a large power unit that occurred, during the runups, when approaching the first balance resonance. The numerical results confirmed the suspect that this high vibration was caused by a shaft bow. Then, the machine model was used also to study and optimize a corrective action that allowed the operating speed to be reached and the shaft bow to be eliminated by means of the turbine heating caused by a load rise. The successful results obtained with the machine maintenance carried out considering the indications provided by the model-based diagnostic and prognostic analyses are shown and discussed.
Dynamic Balancing of Two-DOF Parallel Mechanisms Using a Counter-Mechanism
Authors: Laliberté Thierry , Gosselin Clément
Published: February 2014

Dynamic balancing generally involves the static balancing of a mechanism using countermasses followed by the dynamic balancing of the inertia using counter-rotations. This approach requires that the statically balanced mechanism have a constant inertia for any configuration. Two of the main drawbacks of dynamic balancing are a significant increase in mass and actuation inertia. In this paper, static balancing strategies are optimized regarding the addition of mass and actuation inertia using Lagrange multipliers. The results are optimal mass-inertia curves which are akin to Pareto curves. Optimal static balancing rules are obtained and a comparison of balancing strategies shows that relaxing the constant inertia constraint may significantly reduce the total mass and actuation inertia. Then, a counter-mechanism is introduced in order to dynamically balance a mechanism with variable inertia. The conditions for which the counter-mechanism matches the inertia of the main mechanism for any configuration are derived. The significant influence of the radius of gyration of the counter-inertias on the optimal mass-inertia curves is revealed. Additionally, the advantages of counter-mechanisms over counter-rotations are demonstrated. Finally, examples of dynamically balanced mechanisms and a prototype are presented in order to illustrate the concepts.