bluuebunny/crossref_metadata_2025 huggingface dataset:
Severity of liver disease among chronic hepatitis C patients: An observational study of 4594 patients in five European countries
Authors: Marcellin Patrick , Grotzinger Kelly , Theodore Dickens , Demuth Dirk , Manns Michael , Bañares Cañizares Rafael , Pike James , Forssen Ulla M
Published: August 2014

Background and Aim

Assessment of the severity of liver disease following infection with hepatitis C virus (HCV) is important in treatment selection and prognosis. As invasive liver biopsy procedures are regarded as the reference method to assess the stage of fibrosis, it is important to identify patient characteristics that are predictive of liver fibrosis severity. The aim of the study was to describe the distribution of liver severity scores, clinical characteristics, and physicians' assessment of fibrosis among HCV patients in five European countries.

Methods

This cross‐sectional study retrospectively reviewed the medical records of patients who were chronically infected with HCV in 2006. Patients managed for HCV at any of 60 sites in France, Germany, Italy, Spain, and the UK were included. Data collected included patient demographics and clinical characteristics. A combination of univariate and multivariate regression analyses were used to identify predictors of fibrosis severity and factors associated with undergoing biopsy.

Results

Four thousand five hundred and ninety‐four chronically infected HCV patients were included in this analysis. Management approaches differed between countries, with variations in biopsy use (59.3–18.4%) and preferred fibrosis scoring systems. Where histology results were available, 43.4%, 23.8%, and 32.9% had mild, moderate, and severe fibrosis, respectively. Factors associated with undergoing a biopsy included male gender and co‐infection with hepatitis B virus. Chronic alcoholism, a lower first platelet count, and older age were predictors of increased liver fibrosis severity.

Conclusions

These data suggest that there are major differences in how specialists manage their HCV patients across five major European countries.
Detection of endolithic spatial distribution in marble stone
Authors: CASANOVA MUNICCHIA A. , PERCARIO Z. , CANEVA G.
Published: August 2014

The penetration of endolithic microorganisms, which develop to depths of several millimetres or even centimetres into the stone, and the diffusion of their extracellular substances speeds up the stone deterioration process.

The aim of this study was to investigate, using a confocal laser scanning microscopy with a double‐staining, a marble rock sample by observing the endolithic spatial distribution and quantifying the volume they occupied within the stone, in order to understand the real impact of these microorganisms on the conservation of stone monuments.

Often the only factors taken into account by biodeterioration studies regarding endolithic microorganisms, are spread and depth of penetration. Despite the knowledge of three‐dimensional spatial distribution and quantification of volume, it is indispensable to understand the real damage caused by endolithic microorganisms to stone monuments.

In this work, we analyze a marble rock sample using a confocal laser scanning microscopy stained with propidium iodide and Concavalin‐A conjugate with the fluorophore Alexa Fluor 488, comparing these results with other techniques (SEM microscope, microphotographs of polished cross‐sections and thin‐section, PAS staining methods), An image analysis approach has also been applied.

The use of confocal laser scanning microscopy with double staining shows clear evidence of the presence of endolithic microorganisms (cyanobacteria and fungi) as well as the extracellular polymeric substance matrix in a three‐dimensional architecture as part of the rock sample, this technique, therefore, seems very useful when applied to restoration interventions on stone monuments when endolithic growth is suspected.
Synthesis and microstructural studies of annealed Cu2O/CuxS bilayer as transparent electrode material for photovoltaic and energy storage devices
Authors: TALEATU B. A. , ARBAB E. A.A. , OMOTOSO E. , MOLA G. T.
Published: August 2014

Cu2O thin film and a transparent bilayer have been fabricated by electrodeposition method. The growths were obtained in potentiostatic mode with gradual degradation of anodic current. X‐ray diffraction (XRD) study showed that the bilayer is polycrystalline and it possesses mixture of different crystallite phases of copper oxides. Surface morphology of the films was investigated by scanning electron microscopy (SEM). The SEM images revealed that the films were uniformly distributed and the starting material (Cu2O) had cubical structure. Grains agglomeration and crystallinity were enhanced by annealing. Optical studies indicated that all the samples have direct allowed transition. Energy band gap of the bilayer film was reduced by annealing treatment thus corroborating quantum confinement upshot.
Fabrication of a Movable Obturator Following Maxillary Reconstruction with Slit‐Shaped Fenestration
Authors: Murakami Mamoru , Nishi Yasuhiro , Umezono Minoru , Kamashita Yuji , Nishimura Masahiro
Published: August 2014

Extensive maxillary resection has generally been reconstructed with free skin flaps. Because drooping of the transferred flap causes instability of the obturator prosthesis, maxillary reconstruction often incorporates a slit‐shaped oronasal fenestration. Although obturator prostheses for edentulous patients are stabilized with the help of oronasal slits, those for dentate patients are unstable because of flap mobility, resulting in a harmful lateral force exerted on the abutment teeth, causing dislodging of the denture. This report evaluates the benefits of a movable obturator prosthesis for a 60‐year‐old dentulous patient with maxillary sinus carcinoma. The patient underwent left‐sided total maxillectomy, and the defect was reconstructed with a slit‐shaped fenestration using a rectus abdominis flap. A conventional obturator prosthesis was inserted; however, drooping of the flap caused instability of the obturator, resulting in nasal regurgitation and fracture of the clasp. To solve this problem, we designed an obturator prosthesis with a movable connection consisting of a ball attachment (patrix) in the metal base and a socket (matrix) in the obturator, which acted as a stress breaker against the harmful force exerted by the flap. Application of this movable obturator prosthesis was a useful solution for a compromising situation created by the surgical procedure. No clinical disorders were observed at the 3‐year follow‐up.
Deletion of membrane‐associated Asp23 leads to upregulation of cell wall stress genes in Staphylococcus aureus
Authors: Müller Marret , Reiß Swantje , Schlüter Rabea , Mäder Ulrike , Beyer Anica , Reiß Wenke , Marles‐Wright Jon , Lewis Richard J. , Pförtner Henrike , Völker Uwe , Riedel Katharina , Hecker Michael , Engelmann Susanne , Pané‐Farré Jan
Published: July 2014

With about 25 000 molecules per cell, Asp23 is one of the most abundant proteins in Staphylococcus aureus. Asp23 has been characterized as a protein that, following an alkaline shock, accumulates in the soluble protein fraction. Transcription of the asp23 gene is exclusively regulated by the alternative sigma factor σB, which controls the response of the bacterium to environmental stress. Sequence analysis identified Asp23 as a member of the widely distributed Pfam DUF322 family, precluding functional predictions based on its sequence. Using fluorescence microscopy we found that Asp23 colocalized with the cell membrane of Staphylococcus aureus. Since Asp23 has no recognizable transmembrane spanning domains, we initiated a search for proteins that link Asp23 to the cell membrane. We identified SAOUHSC_02443 as the Asp23 membrane anchor and have renamed it AmaP (Asp23 membrane anchoring protein). Deletion of the asp23 gene led to an upregulation of the cell wall stress response. In summary, we have identified Asp23 as a membrane‐associated protein and we suggest a function for Asp23 in cell envelope homoeostasis.
Evaluation of a temperate climate mosquito, Ochlerotatus detritus (=Aedes detritus), as a potential vector of Japanese encephalitis virus
Authors: MACKENZIE‐IMPOINVIL L. , IMPOINVIL D. E. , GALBRAITH S. E. , DILLON R. J. , RANSON H. , JOHNSON N. , FOOKS A. R. , SOLOMON T. , BAYLIS M.
Published: August 2014

The U.K. has not yet experienced a confirmed outbreak of mosquito‐borne virus transmission to people or livestock despite numerous autochthonous epizootic and human outbreaks of mosquito‐borne diseases on the European mainland. Indeed, whether or not British mosquitoes are competent to transmit arboviruses has not been established. Therefore, the competence of a local (temperate) British mosquito species, Ochlerotatus detritus (=Aedes detritus) (Diptera: Culicidae) for transmission of a member of the genus Flavivirus, Japanese encephalitis virus (JEV) as a model for mosquito‐borne virus transmission was assessed. The JEV competence in a laboratory strain of Culex quinquefasciatus (Diptera: Culicidae), a previously incriminated JEV vector, was also evaluated as a positive control. Ochlerotatus detritus adults were reared from field‐collected juvenile stages. In oral infection bioassays, adult females developed disseminated infections and were able to transmit virus as determined by the isolation of virus in saliva secretions. When pooled at 7–21 days post‐infection, 13% and 25% of O. detritus were able to transmit JEV when held at 23 °C and 28 °C, respectively. Similar results were obtained for C. quinquefasciatus. To our knowledge, this study is the first to demonstrate that a British mosquito species, O. detritus, is a potential vector of an exotic flavivirus.
Proposing nutrients and nutrient levels for rice fortification
Authors: de Pee Saskia
Published: August 2014

Micronutrient deficiencies are often linked to low dietary diversity. Rice fortification could substantially increase micronutrient intake in countries where rice is a staple food. The World Health Organization (WHO) interim consensus statement on maize and wheat flour fortification is based on the premise of the public health importance of specific micronutrient deficiencies and evidence of the benefits of increased micronutrient intake. Since this rationale for maize and wheat flour also applies to rice, it is recommended to fortify rice with iron, folic acid, vitamin B12, vitamin A, and zinc, as well as with thiamin, vitamin B6, and niacin, as polished rice has low levels of these micronutrients. To achieve intake that meets the estimated average requirement of adults, the following levels are recommended where rice consumption is 150–300 g/cap/day (mg/100 g): iron, 7; folic acid, 0.13; vitamin B12, 0.001; vitamin A, 0.15; zinc, 6; thiamin, 0.5; niacin, 7; and vitamin B6, 0.6. These concentrations can be achieved at a 1:100 blending ratio of fortified:unfortified kernels. The costs of rice fortification are largely determined by the manufacturing of the fortified kernels rather than by the number of micronutrients that are added. These are general recommendations that can be adjusted locally, and monitoring and impact evaluation should accompany the introduction of rice fortification.
Rice industrial processing worldwide and impact on macro‐ and micronutrient content, stability, and retention
Authors: Atungulu Griffiths G. , Pan Zhongli
Published: August 2014

Various processing methods are used in the food industry worldwide to produce numerous rice products with desirable sensory qualities based on cultural and cooking preferences and nutritional considerations. The processes result in variable degrees of macro‐ and micronutrient content, stability, and retention, depending on rice variety and original nutritional quality. In this article, modern and traditional premilling, milling, and postmilling processing methods of different rice types are comprehensively reviewed. The implications of industrial rice processing methods, especially milling, as well as techniques for nutrient extraction, transfer, and enhancement, such as rice parboiling, sprouting, and fortification, for macro‐ and micronutrient content and consumer acceptance of the products, are documented. Socioeconomic constraints facing various aspects of rice processing methods are also discussed. This article reviews up‐to‐date research on rice industrial processing worldwide and aims to benefit engineers dealing with food processing, nutritionists and dieticians, food companies, education and research institutions, and quality‐control and safety managers.
Integumental buffering in an alpine grasshopper
Authors: Hawes Timothy C.
Published: August 2014

In most freeze tolerant insects, the tolerance of the formation of internal body ice is arrived at by a two‐step process: (S‐1) a period of supercooling of the body fluids that is followed by (S‐2) the freezing event. To date, the necessity of S‐1 remains to be questioned seriously. The present study reports evidence that S‐1 may be almost completely substituted or superseded in large‐bodied insects by integumental buffering. In the New Zealand alpine grasshopper Sigaus australis Hutton, there is a substantial difference between external and body core temperatures at the moment when internal ice nucleation is registered. Using the invagination of the pleural suture as a nondetrimental proxy for the core and the sclerotized postnotum as a measure of surface temperature, comparisons of the temperature of crystallization (Tc) show a highly significant difference (P < 0.001; Kolmogorov–Smirnov test). Proxy core Tc values are in the range from −0.11 to −4.78 °C compared with the range of −4.1 to −14.2 °C in external proxy Tc values. Although a thermal lag may sometimes be quietly assumed in measurements of Tc, a temperature differential of this size (approximately 6 °C), which is equivalent to the entire supercooling potential of many freeze tolerant insects, is of particular note. These findings have wider application to other large‐bodied insects with similarly well‐developed integumental protection.
Differential expression proteins associated with bud dormancy release during chilling treatment of tree peony (Paeonia suffruticosa)
Authors: Zhang Y. X. , Yu D. , Tian X. L. , Liu C. Y. , Gai S. P. , Zheng G. S.
Published: August 2014

Endo‐dormant flower buds of tree peony must have sufficient chilling duration to reinitiate growth, which is a major obstacle to the forcing culture of tree peony in winter. We used a combination of two‐dimensional gel electrophoresis (2‐DE) and matrix‐assisted laser desorption/ionisation time of flight/time of flight mass spectrometry (MALDI‐TOF/TOF MS) to identify the differentially expressed proteins of tree peony after three different chilling treatments: endo‐dormancy, endo‐dormancy release and eco‐dormancy stages. More than 200 highly reproducible protein spots were detected, and 31 differentially expressed spots (P < 0.05) were selected for further analysis. Finally, 20 protein spots were confidently identified from databases, which were annotated and classified into seven functional categories: response to abiotic or biotic stimulus (four), metabolic processes (four), other binding (three), transcription or transcription regulation (two), biological processes (one), cell biogenesis (one) and unclassified (five). The results of qPCR of five genes were mainly consistent with that of the protein accumulation analysis as determined by 2‐DE. This indicated that most of these genes were mainly regulated at transcriptional level. The activity of nitrate reductase and pyruvate dehydrogenase E1 was consistent with the 2‐DE results. The proteomic profiles indicated activation of citrate cycle, amino acid metabolism, lipid metabolism, energy production, calcium signalling and cell growth processes by chilling fulfilment to facilitate dormancy release in tree peony. Analysis of functions of identified proteins will increase our knowledge of endo‐dormancy release in tree peony.
Information Sharing in a Manufacturer–Supplier Relationship: Suppliers' Incentive and Production Efficiency
Authors: Chen Ying‐Ju , Deng Mingcherng
Published: August 2014

While there have been vast discussions on the materialistic benefits of continuous improvement from the Toyota and Honda experiences, the academic literature pays little attention to information sharing. In this study, we construct a dynamic adverse selection model in which the supplier privately observes her production efficiency, and in the contractual duration the manufacturer obtains an informative but imprecise signal regarding this private efficiency. We show that despite the disclosure of proprietary information, information sharing may benefit the supplier; the supplier's voluntary participation is more likely to occur when the shared information is rather imprecise. On the other hand, our analysis also reveals that this information sharing unambiguously gives rise to an upward push of the production quantity, and may sometimes lead to an upward distortion that ultimately hurts the supply chain. We also document the non‐trivial impact of the timing of information sharing on the supplier's incentive to participate.
Buyer Behavior in Quality‐Dominated Multi‐Sourcing Recyclable‐Material Procurement of Green Supply Chains
Authors: Sheu Jiuh‐Biing
Published: August 2014

This study presents a multi‐methodological approach to investigate buyer behavior in quality‐dominated multi‐sourcing recyclable‐material procurement of green supply chains. This work hypothesizes the correlations between buyer perceptions of supply and relational quality, quality attitude, psychological benefits, and willingness to pay. This is followed by conducting a normative analysis, where the postulated hypotheses are incorporated into a buyer behavior model which characterizes buyer decisions regarding multi‐supplier selection and price negotiations using multinomial logit model and Nash bargaining game theory. Through an empirical study, this work demonstrates that the proposed buyer behavior theory and hypotheses hold, and upport the analytical results yielded from the normative analysis. Analytical results indicate that supply‐ and relationship‐quality positively affect buyer quality attitude in the rational and affective cognition domains, and thus jointly determine buyer decisions regarding supplier selection and price negotiations in multiple sourcing green procurement. Nevertheless, the aforementioned effects are moderated by buyer psychological benefits. Additionally, this study demonstrates a phenomenon known as “buyer's supply surplus”, which articulates the negative effect of buyer attitude towards channel relationship quality on willingness to pay. This can also rationalize why a buyer favors choosing suppliers with superior relational quality for the achievement of lower negotiated prices.
Invoking Simplicity: ‘Alternative’ Food and the Reinvention of Distinction
Authors: Paddock Jessica
Published: August 2014

Contributing to debates that question the prevalence of distinction surrounding contemporary food culture, this article considers the persistence of social differentiation within the context of ‘alternative’ food practice. Doing so is predicated upon the impasse between arguments that food offers a means of conferring status on the one hand, and a means for wide participation in cultural consumption on the other. Starting from this binary of ‘omnivorousness’ (Peterson and Kern) and ‘distinction’ (Bourdieu), this case‐study explores a field of alternative food consumption including a farmers' market and community food co‐operative. Here, despite wider claims that food ceases to provide means of social differentiation (Bennett et al.) we find that discourses of distinction resonate across this case‐study, finding expression in participant accounts of food practice, and in discourse framing alternative food as a solution to public policy problems such as social exclusion, unsustainability and lack of integrity in contemporary food systems. Of some consequence to initiatives seeking to develop equitable and sustainable alternatives to conventional foodways, distinction, it is argued, is reinvented under the guise of rustic simplicity.
Perception‐based 3D tactile rendering from a single image for human skin examinations by dynamic touch
Authors: Kim K. , Lee S.
Published: August 2014

Background/aims

Diagnosis of skin conditions is dependent on the assessment of skin surface properties that are represented by more tactile properties such as stiffness, roughness, and friction than visual information. Due to this reason, adding tactile feedback to existing vision based diagnosis systems can help dermatologists diagnose skin diseases or disorders more accurately. The goal of our research was therefore to develop a tactile rendering system for skin examinations by dynamic touch.

Methods

Our development consists of two stages: converting a single image to a 3D haptic surface and rendering the generated haptic surface in real‐time. Converting to 3D surfaces from 2D single images was implemented with concerning human perception data collected by a psychophysical experiment that measured human visual and haptic sensibility to 3D skin surface changes. For the second stage, we utilized real skin biomechanical properties found by prior studies. Our tactile rendering system is a standalone system that can be used with any single cameras and haptic feedback devices.

Results

We evaluated the performance of our system by conducting an identification experiment with three different skin images with five subjects. The participants had to identify one of the three skin surfaces by using a haptic device (Falcon) only. No visual cue was provided for the experiment. The results indicate that our system provides sufficient performance to render discernable tactile rendering with different skin surfaces.

Conclusion

Our system uses only a single skin image and automatically generates a 3D haptic surface based on human haptic perception. Realistic skin interactions can be provided in real‐time for the purpose of skin diagnosis, simulations, or training. Our system can also be used for other applications like virtual reality and cosmetic applications.
Design and Control of the IBM Power 775 Supercomputer Water Conditioning Unit
Authors: Ellsworth Michael J. , Zoodsma Randy J. , Cascio Frank , Behrendt Eileen
Published: July 2014

In 2011, IBM announced the Power 775 supercomputing node/system which, for the time, was a significant increase in computing performance and energy efficiency. The system was designed from the start with water cooling in mind. The result: a system with greater than 95% of its heat load conducted directly to water and a system that, together with a rear door heat exchanger (HX), removes 100% of its heat load to water with no requirement for room air conditioning. In addition to direct water cooling the processor, the memory, power conversion, and input–output electronics also conduct their heat directly to water. Also included within the framework of the system is a disk storage unit (i.e., disk enclosure) containing an interboard air-to-water HX. The heart of the water cooling system is the water conditioning unit (WCU). The WCU circulates system water at a controlled temperature and flow rate while also transferring the electronics heat load to the data center facility building chilled water (BCW) system. The brain for this system is the motor drive and control assembly (MDA-WCU). In addition to the pump motor drive function, the MDA-WCU contains the control circuitry and associated firmware that maintains system water at a prescribed temperature above the room dew point irrespective of system and or facilities thermal/flow transients. It is also capable of error detection and fault isolation that, together with higher level system firmware, facilitates serviceability, and availability. The paper will present the WCU and MDA-WCU design with an emphasis on the control methodologies and algorithms.
Nonlinear Deformation Behavior of Bolted Flanges Under Tensile, Torsional, and Bending Loads
Authors: Wu Zhijun , Nassar Sayed A. , Yang Xianjie
Published: August 2014

A bolted flange may be subjected to the axial tensile, torsional, and bending external loads in service. The axial tensile, torsional, and bending resistance of the bolted flange is vital for the system vibration, dynamic strength, and reliability. This paper investigates the nonlinear deformation behavior of bolted flanges under tensile, torsional, and bending loads, using finite element analysis (FEA). Even though the bolted flange materials may still deform elastically, the variation in contact area due to the external loading may still cause nonlinear deformation of the flanges. In this study, finite element simulation is used for investigating the respective nonlinear deformation behavior of a preloaded bolted flange under tensile, torsional, and bending loads, and to determine the corresponding stiffness values for each loading.
Recommendations for Energy–Water–Food Nexus Problems
Authors: Wong Kaufui Vincent , Pecora Charles
Published: August 2014

Around the world, climate change has brought about seemingly more incidences of climate extremes. Sub-Saharan Africa is a prime example of a region with many countries suffering from water scarcity. Water scarcity is quite possibly the most important issue that exists, seeing as it is the one essential resource for humans and all other life. Water scarcity in this region is somewhat ironic because of the numerous freshwater rivers that run throughout the region. The main reason for this water problem is the mismanagement and lack of energy required to redistribute the water. The water issue is inevitably linked to both energy resources and food resources. Water is the basis for all agriculture and is required for livestock. Water is also needed for almost any type of energy conversion. In a fossil fuel power plant, water is both the working fluid of the system and the coolant used in the condenser. In dams, the potential stored in flowing water is the basis of the creation of energy. Water, conversely, requires power to be transported and treated for drinking and agriculture. Sub-Saharan Africa has nearly maximized the energy of its large rivers, thus new sources of energy must be implemented to help with the energy crisis. A couple of the possibilities are fossil fuel power plants, geothermal power plants, and solar panels. Solar panels require a large amount of capital to build, but are nearly free to maintain, and can be cheaper in the long run. Solar power is an undeniably renewable resource and does not adversely affect the environment. Solar power can be utilized both for electricity generation and for irrigation and cooking in remote communities. Geothermal power plants utilize the potential stored in the earth's crust in places with volcanic activity. East Africa has an especially large potential for geothermal energy due to its many volcanoes. As for thermal power plants, combined cycle power plants paired with a salt water cooling system would greatly improve efficiency and drastically decrease water usage. By replacing Rankine cycle power plants that are used in most of Sub-Saharan Africa with either combined cycle plants or gas cycle plants, efficiencies would improve and far less water for cooling would be used in the system.
A Thermo-Economic Study of Storage Integration in Hybrid Solar Gas-Turbine Power Plants
Authors: Spelling James , Guédez Rafael , Laumert Björn
Published: August 2014

A thermo-economic simulation model of a hybrid solar gas-turbine (HSGT) power plant with an integrated storage unit has been developed, allowing determination of the thermodynamic and economic performance. Designs were based around two representative industrial gas-turbines: a high efficiency machine and a low temperature machine. In order to examine the trade-offs that must be made, multi-objective thermo-economic analysis was performed, with two conflicting objectives: minimum investment costs and minimum specific carbon dioxide (CO2) emissions. It was shown that with the integration of storage, annual solar shares above 85% can be achieved by HSGT systems. The levelized electricity cost (LEC) for the gas-turbine system as this level of solar integration was similar to that of parabolic trough plants, allowing them to compete directly in the solar power market. At the same time, the water consumption of the gas-turbine system is significantly lower than contemporary steam-cycle based solar thermal power plants.
Effect of Dispersion Homogeneity on Specific Heat Capacity Enhancement of Molten Salt Nanomaterials Using Carbon Nanotubes
Authors: Jo Byeongnam , Banerjee Debjyoti
Published: August 2014

The specific heat capacity of a carbonate salt eutectic-based carbon nanotube nanomaterial was measured in present study. Differential scanning calorimeter (DSC) was used to measure the specific heat capacity of the nanomaterials. The specific heat capacity value in liquid phase was compared with that of a pure eutectic. A carbonate salt eutectic was used as a base material, which consists of lithium carbonate and potassium carbonate by 62:38 molar ratio. Multiwalled carbon nanotubes (CNT) at 1% mass concentration were dispersed in the molten salt eutectic. In order to find an appropriate surfactant for synthesizing molten salt nanomaterials, three surfactants, sodium dodecyl benzene sulfonate (SDBS), sodium dodecyl sulfate (SDS), and gum arabic (GA), at 1% mass concentration with respect to the salt eutectic were added. In preparation of dehydrated nanomaterials, water was evaporated by heating vials on a hot plate. Three different temperature conditions (120, 140, and 160 °C) were employed to investigate the effect of dispersion homogeneity of the nanotubes in the base material on the specific heat capacity of the nanomaterials. It is expected that the amount of agglomerated nanotubes decreases with increase of evaporation temperature (shorter elapsed time for evaporation). The results showed that the specific heat capacity of the nanomaterials was enhanced up to 21% in liquid phase. Additionally, it was found that the specific heat capacity enhancement of the nanomaterials, which contained SDS, was more sensitive to the evaporation time. Also, it can be decided that GA is the most appropriate to disperse CNT into the aqueous salt solution. Finally, CNT dispersion was confirmed with scanning electron microscope (SEM) images for pre-DSC and post-DSC samples. Furthermore, theoretical predictions of the specific heat capacity were compared with the experimental results obtained in present study.
Distributed Gaussian Process Regression Under Localization Uncertainty
Authors: Choi Sungjoon , Jadaliha Mahdi , Choi Jongeun , Oh Songhwai
Published: August 2014

In this paper, we propose distributed Gaussian process regression (GPR) for resource-constrained distributed sensor networks under localization uncertainty. The proposed distributed algorithm, which combines Jacobi over-relaxation (JOR) and discrete-time average consensus (DAC), can effectively handle localization uncertainty as well as limited communication and computation capabilities of distributed sensor networks. We also extend the proposed method hierarchically using sparse GPR to improve its scalability. The performance of the proposed method is verified in numerical simulations against the centralized maximum a posteriori (MAP) solution and a quick-and-dirty solution. We show that the proposed method outperforms the quick-and-dirty solution and achieve an accuracy comparable to the centralized solution.
A Simplified Two-Stage Design of Linear Discrete-Time Feedback Controllers
Authors: Radisavljevic-Gajic Verica
Published: August 2014

In this paper, we have shown how to simplify an algorithm for the two-stage design of linear feedback controllers by reducing computational requirements. The algorithm is further simplified for linear discrete-time systems with slow and fast modes (multitime scale systems or singularly perturbed systems), providing independent and accurate designs in slow and fast time scales. The simplified design procedure and its very high accuracy are demonstrated on the eigenvalue assignment problem of a steam power system.
In Situ Observation of Deformation Behavior of Membrane Electrode Assembly Under Humidity Cycles
Authors: Kai Yusuke , Kitayama Yuki , Omiya Masaki , Uchiyama Tomoaki , Kumei Hideyuki
Published: August 2014

The mechanical reliability of the membrane electrode assembly (MEA) in polymer electrolyte fuel cells (PEFCs) is a major concern with respect to fuel cell vehicles. When PEFCs generate power, water is generated. The proton exchange membrane (PEM) swells in wet conditions and shrinks in dry conditions. These cyclic conditions induce mechanical stress in the MEA, and cracks are formed. Failure of the MEA can result in leaking of fuel gases and reduced output power. Therefore, it is necessary to determine the mechanical reliability of the MEA under various mechanical and environmental conditions. The purpose of the present paper is to observe the deformation behavior of the MEA under humidity cycles. We have developed a device in which the constrained condition of the GDL is modeled by carbon bars of 100 to 500 μm in diameter. The carbon bars are placed side by side and are pressed against the MEA. The device was placed in a temperature and humidity controlled chamber, and humidity cycles were applied to the specimen. During the tests, cross sections of the specimen were observed by microscope, and the strain was calculated based on the curvature of the specimen. The temperature in the test chamber was varied from 25 to 80 °C, and the relative humidity was varied from 50 to 100%RH, and the wet condition was also investigated. The results revealed that the MEA deformed significantly by swelling and residual deformation was observed under the dry condition, even for one humidity cycle. The crack formation criteria for one humidity cycle corresponded approximately with those of the static tensile tests. The results of the humidity cycle tests followed Coffin–Manson law, and the number of cycles until crack formation corresponded approximately with the results of the mechanical fatigue tests. These results will be valuable in the critical design of durable PEFCs.
Accurate, Robust, and Real-Time Pose Estimation of Finger
Authors: Yun Youngmok , Agarwal Priyanshu , Deshpande Ashish D.
Published: August 2014

Many robotic applications need an accurate, robust, and fast estimation of finger pose. We present a novel finger pose estimation method using a motion capture system. The method combines a system identification stage and a state tracking stage in a unified framework. The system identification stage develops an accurate model of a finger, and the state tracking stage tracks the finger pose with the extended Kalman filter (EKF) algorithm based on the model obtained in the system identification stage. The algorithm is validated by simulation, and experiments with a human subject and a robotic finger. The experimental results show that the method can robustly estimate the finger pose at a high frequency (greater than 1 kHz) in the presence of measurement noise, occlusion of markers, and fast movement.
A Selective Multiclass Support Vector Machine Ensemble Classifier for Engineering Surface Classification Using High Definition Metrology
Authors: Du Shichang , Liu Changping , Xi Lifeng
Published: August 2014

The surface appearance is sensitive to change in the manufacturing process and is one of the most important product quality characteristics. The classification of workpiece surface patterns is critical for quality control, because it can provide feedback on the manufacturing process. In this study, a novel classification approach for engineering surfaces is proposed by combining dual-tree complex wavelet transform (DT-CWT) and selective ensemble classifiers called modified matching pursuit optimization with multiclass support vector machines ensemble (MPO-SVME), which adopts support vector machine (SVM) as basic classifiers. The dual-tree wavelet transform is used to decompose three-dimensional (3D) workpiece surfaces, and the features of workpiece surface are extracted from wavelet sub-bands of each level. Then MPO-SVME is developed to classify different workpiece surfaces based on the extracted features and the performance of the proposed approach is evaluated by computing its classification accuracy. The performance of MPO-SVME is validated in case study, and the results demonstrate that MPO-SVME can increase the classification accuracy with only a handful of selected classifiers.
Numerical Simulation of Turbulent Impingement Cooling
Authors: Abdon Andreas , Sundén Bengt
Published: July 2014

Simulations of turbulent impinging jet heat transfer for different nozzle configurations using Reynolds averaged governing equations and two-equation turbulence models have been conducted. The considered nozzle configurations are a square-edged orifice and a pipe exit. The results for a jet Reynolds number of 10000 and dimensionless nozzle-to-plate distance of 2 show that the heat transfer is well predicted for the pipe configuration but underpredicted for the orifice. The disagreement may be partly explained by underprediction of turbulence in the stagnation region and inaccurate treatment of the wall jet boundary layer transition. An investigation of the local heat transfer distribution for the orifice reveals two local maxima. These are related to an accelerating laminar boundary layer and the transition process of the wall jet, respectively, for the calculations. The application of a realizability constraint on the models leads to reduced turbulence levels, not only in the stagnation region, but also in the throttled flow of the orifice configuration. This improves the prediction of heat transfer and nozzle exit turbulence levels significantly.
Complex Variable Filtering: The Next Step in Rotor Diagnostics
Authors: Franklin Wes , Bently Donald E.
Published: July 2014

Currently most rotor diagnostic algorithms focus on extracting as much information as possible from the signal of a single transducer. This limits these algorithms to only processing information about the projection of the rotor motion onto the probe axis. Utilizing single probes is adequate for isotropic systems where the projections are the same for any probe orientation. However, for anisotropic systems the results of the algorithm can be different depending on the orientation of the measurement transducer. This leads to the blind men and elephant conflict, multiple descriptions of the same animal, or in our case rotor motion. For example, if the transducer is located on the minor axis a great running machine, on the major axis a machine that needs balancing. The phase is also inconsistent, rotate the transducer a few degrees and the indicated phase jumps drastically. If the transducer is on the ellipse axis the high spot and heavy spot are together below the resonance, move the probe off the axis and the high spot and heavy spot are no longer related. More sophisticated diagnostic methodologies which correlate data from multiple axial locations, such as relative phase and modeshape, are affected even more than balancing by the phase inconsistency. What is really desired, is information about the actual motion of the shaft in the two dimensional plane. Up until recently the only data presentation format that addressed the planer motion was orbit. Orbits are powerful diagnostic tools, but have the limitation of only showing motion at one speed. What is needed are similar processing techniques that present complete motion over the entire speed range and report the same information for all probe orientations, such as complex variable filtering. This paper presents the concept of complex variable filtering and explores some situations in which it provides superior results to those obtained utilizing conventional single probe techniques.
Experimental Investigation of Misaligned Rotors
Authors: Rao J. S. , Sreenivas R. , Chawla A.
Published: July 2014

This paper is concerned with an experimental investigation of misaligned rotors. Phenomena observed in the field by different authors are substantiated through these experimental results.
Analysis of 8 Centrifugal Compressor Impellers Using Two Different CFD Methods: Part II — Blockage and Slip Characteristics
Authors: Oh JongSik
Published: July 2014

As the second part of the author’s study, the aerodynamic exit blockage and the slip factor of 8 centrifugal compressor impellers are investigated, when the flow rate is changed from numerical stall to choke, using three-dimensional Navier-Stokes analysis results. Based on all the exit blockage distributions, an improved model equation with two adjusting coefficients is developed for the use in design processes with the agile engineering purpose. A popular expression of simple slip factors, the Wiesner’s equation, cannot be applied in design processes when more accurate prediction is strongly required at design and off-design points. Slip factor variation is found to be also influenced by the blade loadings at midspan. When the flow rate is changed, a pattern of the slip factor variations is assumed to be a simple form which can be explained using midspan blade loading distributions.
Career Opportunities in Power Generation
Authors: Cloyd Scott T.
Published: July 2014

The Power Generation Industry has a wide variety of challenging career opportunities for engineers. This paper provides an overview of the types of job opportunities that are currently available within the fossil fuel segment of the industry with a focus on gas and steam turbine based power plants. The challenges within these jobs and ability to alter career paths as individual interests’ change are also described.
High Temperature Fatigue/Creep/Environment Interactions in Compressor Alloys
Authors: Evans W. John , Jones J. Paul , Bache Martin R.
Published: July 2014

The high temperature fatigue response of titanium and nickel alloys destined for high performance gas turbine applications is considered with particular emphasis given to the role of creep and environmental damage during crack growth. In an attempt to partition the respective contributions from these two rate controlling factors, data are presented for a range of temperature, stress ratio and pressure conditions. The implications for the extended use of such alloys in future gas turbine designs are discussed.
A Navier-Stokes Based Strategy for the Aerodynamic Optimisation of a Turbine Cascade Using a Genetic Algorithm
Authors: Cravero Carlo , Satta Antonio
Published: July 2014

The problem of turbine cascade design is considered using automatic optimisation strategies. After the profile parameterisation, two different models are considered to simulate the cascade performances: experimental correlations and a Navier-Stokes code. Interesting considerations on the optimisation algorithm can be drawn using correlations because the evaluation of the fitness is almost instantaneous. By fixing certain of the design constraints two optimised configurations are obtained using simplified correlating function or the viscous flow solver. The optimised configurations are then investigated with an accurate viscous flow computation in order to have a deeper insight into the flowfield.
A Predictive Modeling Approach to Analyze Data in EEG–fMRI Experiments
Authors: Ferdowsi Saideh , Sanei Saeid , Abolghasemi Vahid
Published: August 2014

In this paper, a novel technique based on blind source extraction (BSE) using linear prediction is proposed to extract rolandic beta rhythm from electroencephalogram (EEG) recorded in a simultaneous EEG–fMRI experiment. We call this method CLP–BSE standing for constrained-linear-prediction BSE. Extracting event-related oscillations is a crucial task due to nonphase-locked nature and inter-trial variability of this event. The main objective of this work is to extract rolandic beta rhythm to measure event-related synchronization (ERS) with acceptable signal-to-noise ratio (SNR). The extracted rhythm is utilized for constructing a regressor to analyze functional magnetic resonance imaging (fMRI). The proposed method is a semi-blind technique which uses a spatio-temporal constraint for beta rhythm extraction. This constraint is derived from recorded EEG signals based on the prior knowledge about the frequency and location of the source of interest. The main reason of employing linear prediction as an effective algorithm to extract the EEG rhythm is the ability of extracting sources which have specific temporal structure. Performance of the proposed method is evaluated using both synthetic and real EEG data. The obtained results show that the proposed technique is able to extract ERS effectively. The maximum percentage of ERS obtained by filtering is 152% while the obtained ERS by CLP–BSE is 214%. In another experiment, the extracted event-related oscillations in beta band are used to make the necessary regressor for fMRI analysis. The results of EEG–fMRI coregistration confirm that there are correlation between the extracted rolandic beta rhythm and simultaneously recorded fMRI. This conclude that, the results of EEG–fMRI combination support the reliability of CLP–BSE output.
An Optimal Preemptive Algorithm for the Single-Server Parallel-Machine Scheduling with Loading and Unloading Times
Authors: Jiang Yiwei , Wang Huijuan , Zhou Ping
Published: August 2014

We study a preemptive scheduling problem on two identical parallel machines that share a common server. Each job has to be loaded by the server before being processed on one of the machines and unloaded by the server after its processing. The loading and unloading times are both equal to one time unit. The goal is to minimize the makespan. We propose a O(n log n) solution algorithm for the preemptive variant of the problem.
Coordination of Expectations: The Eductive Stability Viewpoint
Authors: Desgranges Gabriel
Published: August 2014

The eductive approach consists of finding solutions consistent with common knowledge of individual rationality and the model. An equilibrium is stable whenever it is the unique outcome consistent with these assumptions. This is a strong stability criterion as it relies on no assumption of prior knowledge of others’ expectations. This review presents various (in)stability results. It focuses on the following method: Rewrite the model as a temporary equilibrium map in which the current economic outcome is determined by expectations and characterize stability by contracting properties of this map. The main insight suggested by these results is due to Guesnerie (2002) : Stability is obtained when the actual outcome is not very sensitive to expectations. Additional insights include that agents’ heterogeneity is a source of instability; the ability of prices to transmit information is limited by the quality of private information; and coordination when agents are infinitely lived is difficult because of the large effect of long-run expectations.
People, Places, and Public Policy: Some Simple Welfare Economics of Local Economic Development Programs
Authors: Kline Patrick , Moretti Enrico
Published: August 2014

Most countries exhibit large and persistent geographical differences in wages, income, and unemployment rates. A growing class of place-based policies attempts to address these differences through public investments and subsidies that target disadvantaged neighborhoods, cities, or regions. Place-based policies have the potential to profoundly affect the location of economic activity, along with the wages, employment, and industry mix of communities. These programs are widespread in the United States and throughout the world but have only recently been studied closely by economists. We consider the following questions: Who benefits from place-based interventions? Do the national benefits outweigh the costs? What sorts of interventions are most likely to be effective? To study these questions, we develop a simple spatial equilibrium model designed to characterize the welfare effects of place-based policies on the local and the national economy. Using this model, we critically evaluate the economic rationales for place-based policies and assess the latest evidence on their effects. We conclude with some lessons for policy and directions for future research.