bluuebunny/crossref_metadata_2025 huggingface dataset:
Reduced-Order Modeling of Aeroacoustic Systems for Stability Analyses of Thermoacoustically Noncompact Gas Turbine Combustors
Authors: Hummel Tobias , Temmler Constanze , Schuermans Bruno , Sattelmayer Thomas
Published: September 2015

A methodology is presented to model noncompact thermoacoustic phenomena using reduced-order models (ROMs) based on the linearized Navier–Stokes equations (LNSEs). The method is applicable to geometries with a complex flow field as in a gas turbine combustion chamber. The LNSEs, and thus the resulting ROM, include coupling effects between acoustics and mean fluid flow and are hence capable of describing propagation and (e.g., vortical) damping of the acoustic fluctuations within the considered volume. Such an ROM then constitutes the main building block for a novel thermoacoustic stability analysis method via a low-order hybrid approach. This method presents an expansion to state-of-the-art low-order stability tools and is conceptually based on three core features: First, the multidimensional and volumetric nature of the ROM establishes access to account spatial variability and noncompact effects on heat-release fluctuations. As a result, it is particularly useful for high-frequency phenomena such as screech. Second, the LNSE basis grants the ROM the capability to reconstruct complex acoustic performances physically accurate. Third, the formulation of the ROM in state-space allows convenient access to the frequency and time domain. In the time domain, nonlinear saturation mechanisms can be included, which reproduce the nonlinear stochastic limit cycle behavior of thermoacoustic oscillations. In order to demonstrate and verify the ROM's underlying methodology, a test case using an orifice-tube geometry as the acoustic volume is performed. The generation of the ROM of the orifice tube is conducted in a two-step procedure. As the first step, the geometrical domain is aeroacoustically characterized through the LNSE in frequency domain and discretized via the finite element method (FEM). The second step concerns the actual derivation of the ROM. The high-order dynamical system from the LNSE discretization is subjected to a modal reduction as order reduction technique. Mathematically, this modal reduction is the projection of the high-order (N∼ 200,000) system into its truncated left eigenspace. An order reduction of several magnitudes (ROM order: Nr∼ 100) is achieved. The resulting ROM contains all essential information about propagation and damping of the acoustic variables, and efficiently reproduces the aeroacoustic performance of the orifice tube. Validation is achieved by comparing ROM results against numerical and experimental benchmarks from LNSE–FEM simulations and test rig measurements, respectively. Excellent agreement is found, which grants the ROM modeling approach full eligibility for further usage in the context of thermoacoustic stability modeling. This work is concluded by a methodological demonstration of performing stability analyses of noncompact thermoacoustic systems using the herein presented ROMs.
Low NOx Lean Premix Reheat Combustion in Alstom GT24 Gas Turbines
Authors: Guyot Daniel , Tea Gabrielle , Appel Christoph
Published: September 2015

Reducing gas turbine emissions and increasing their operational flexibility are key targets in today's gas turbine market. In order to further reduce emissions and increase the operational flexibility of its GT24 (60 Hz) and GT26 (50 Hz), Alstom has introduced an improved sequential environmental (SEV) burner and fuel lance into its GT24 and GT26 upgrades 2011 sequential reheat combustion system. Sequential combustion is a key differentiator of Alstom GT24/GT26 engines in the F-class gas turbine market. The inlet temperature for the SEV combustor is around 1000 °C and reaction of the fuel/oxidant mixture is initiated through auto-ignition. The recent development of the Alstom sequential combustion system is a perfect example of evolutionary design optimizations and technology transfer between Alstom GT24 and GT26 engines. Better overall performance is achieved through improved SEV burner aerodynamics and fuel injection, while keeping the main features of the sequential burner technology. The improved SEV burner/lance concept has been optimized toward rapid fuel/oxidant mixing for low emissions, improved fuel flexibility with regard to highly reactive fuels (higher C2+ and hydrogen content), and to sustain a wide operation window. The burner front panel features an improved cooling concept based on near-wall cooling as well as integrated acoustics damping devices designed to reduce combustion pulsations, thus extending the SEV combustor's operation window even further. After having been validated extensively in Alstom's high pressure (HP) sector rig test facility, the improved GT24 SEV burner has been retrofitted into a commercial GT24 field engine for full engine validation during long-term operation. This paper presents the obtained HP sector rig and engine validation results for the GT24 (2011) SEV burner/lance hardware with a focus on reduced NOx and CO emissions and improved operational behavior of the SEV combustor. The HP tests demonstrated robust SEV burner/lance operation with up to 50% lower NOx formation and a more than 70 K higher SEV burner inlet temperature compared to the GT24 (2006) hardware. For the GT24 engine with retrofitted upgrade 2011 SEV burner/lance, all validation targets were achieved including an extremely robust operation behavior, up to 40% lower GT NOx emissions, significantly lower CO emissions at partload and baseload, a very broad operation window (up to 100 K width in SEV combustor inlet temperature), and all measured SEV burner/lance temperatures in the expected range. Sector rig and engine validation results have confirmed the expected SEV burner fuel flexibility (up to 18 vol. % C2+ and up to 5 vol. % hydrogen as standard).
A Numerical Study on CMOD Compliance for Single-Edge Notched Bending Specimens
Authors: Wang Enyang , Zhou Wenxing , Shen Guowu , Duan Daming
Published: September 2015

Several well-known equations for estimating the crack length in the single-edge notched bending (SE(B)) specimens from the normalized crack mouth opening displacement (CMOD) compliance are evaluated based on two-dimensional (2D) and three-dimensional (3D) finite element analyses (FEAs). Two-dimensional FEAs are first carried out to verify the reported accuracy and applicable ranges for each equation based on the plane strain models with six different crack lengths. Three-dimensional FEAs are then carried out to estimate the errors of prediction of equations that evaluate the crack length from the plane stress- and plane strain-based CMOD compliances. Both plane-sided and side-grooved models are included in 3D FEAs and have seven different thickness-to-width ratios. The error of prediction of a given equation is largely impacted by the thickness-to-width ratio, the crack length, the presence of side grooves, and the use of the plane stress- or plane strain-normalized CMOD compliance. Based on the errors of prediction, the relevance of the actual state of stress in the ligament of the SE(B) specimens to the plane strain condition or the plane stress condition is inferred. Knowledge of the relevance of the plane stress condition or the plane strain condition can be used to select the corresponding CMOD compliance in crack length-CMOD equations, and, therefore, the corresponding predictive accuracy can be improved.
A Methodology for Modular and Changeable Design Architecture and Application in Automotive Framing Systems
Authors: ElMaraghy Hoda , AlGeddawy Tarek
Published: September 2015

This paper presents a design methodology to modularize integrated fixtures, such as automotive framing systems, to be quickly and cost effectively reconfigured to accommodate a variety of products. Automotive assembly framing systems are used to accurately position and spot-weld the loosely pre-assembled body-in-white (BIW) car body parts. Auto-assembly systems can handle many car body styles; however, the used model-specific BIW framing systems are large, expensive, and the changeover to accommodate different car models takes considerable time. The proposed modularization design methodology aggregates a set of design structure matrices (DSMs) to represent the required changes in the fixtures, the spatial relationships between the used tools and fixtures, and the flow of exchanged information between them. The best granularity level of the modular fixture design architecture is determined using “Cladistics”: a hierarchical biological classification tool. Different tools within the framing system are combined into switchable modules, which allows these integrated systems to be easily reconfigured between different car body styles (product variants). A case study involving four car body styles is used for illustrating the presented design methodology. Results show the validity of the proposed methodology and demonstrate the obtained design of new modular automotive BIW framing system and the methods used for postprocessing and redesigning to improve the framing system's changeability.
Co-Kriging Method for Form Error Estimation Incorporating Condition Variable Measurements
Authors: Du Shichang , Fei Lan
Published: September 2015

The form error estimation under various machining conditions is an essential step in the assessment of product surface quality generated in machining processes. Coordinate measuring machines (CMMs) are widely used to measure complicated surface form error. However, considering measurement cost, only a few measurement points are collected offline by a CMM for a part surface. Therefore, spatial statistics is adopted to interpolate more points for more accurate form error estimation. It is of great significance to decrease the deviation between the interpolated height value and the real one. Compared to univariate spatial statistics, only concerning spatial correlation of height value, this paper presents a method based on multivariate spatial statistics, co-Kriging (CK), to estimate surface form error not only concerning spatial correlation but also concerning the influence of machining conditions. This method can reconstruct a more accurate part surface and make the estimation deviation smaller. It characterizes the spatial correlation of machining errors by variogram and cross-variogram, and it is implemented on one of the common features: flatness error. Simulated datasets as well as actual CMM data are applied to demonstrate the improvement achieved by the proposed multivariate spatial statistics method over the univariate method and other interpolation methods.
Multifunctional Optimization of Viscoelastic Materials Subjected to Spherical Impact
Authors: Herrenbrück Martin , Duddeck Fabian , Lackner Roman
Published: September 2015

The event of rigid solids impacting a viscoelastic body is encountered in many engineering disciplines. However, for this problem no analytical solution is available, making the proper design of, e.g., protective bodies a difficult task. As a remedy, generally valid solutions in form of nondimensional response curves are presented in this paper, serving as reference for validation purposes or as design charts for the performance-oriented development of impact absorbers. Hereby, the problem of a frictionless rigid sphere impinging a viscoelastic half-space is investigated by finite-element analyses. The general applicability of the results is assured by a transformation to dimensionless problem parameters. For this purpose, the analytical solution by Hertz (1881, “Über die Berührung fester elastischer Körper,” J. die Reine Angew. Math., 1882(92), pp. 156–171) for the purely elastic impact is taken into account. The chosen nondimensional format leads to a reduced number of system parameters, allowing for a compact representation by so-called master curves. From these, optimal material characteristics are found for three different design objectives.
Palmoplantar lichen planus successfully treated with acitretin
Authors: Solak Berna , Kara Rabia Oztas , Kosem Mustafa
Published: September 2015

Palmoplantar lichen planus (PPL) is an uncommon type of lichen planus (LP) that exclusively affects the palms and soles. We report a case of a 50-year-old man who had palmoplantar hyperkeratotic papules and plaques. The patient was diagnosed as a case of PPL by skin biopsy, and treated with acitretin. He showed a good response to acitretin within 2 months. Clinical appearance and some features of PPL may differ from classic LP. Acitretin may be a favourable treatment option for PPL.
OBJECTIVE FUNCTION, LEAN MASS, AND ASSOCIATED GENETIC ADAPTATIONS OF THE OPERATED LEG FOLLOWING TOTAL HIP ARTHROPLASTY
Authors: Okoro T. , Stewart C. , Al-Shanti N. , Lemmey A. , Maddison P. , Andrew J. G.
Published: September 2015

Purpose: To characterize muscle recovery following total hip arthroplasty (THA) combining genetic adaptations in the affected leg with objective function and body composition assessment. Methods: Preoperatively and at six weeks postoperatively, objective function was assessed by: maximal voluntary contraction of the operated leg quadriceps (MVCOLQ) in Newtons (N), 30[Formula: see text]s chair sit-to-stand (ST), and six-minute walk test (6MWT), with lean mass of the operated leg estimated by dual energy X-ray absorptiometry (DEXA). Genetic adaptations were assessed from vastus lateralis (VL) biopsies by quantitative polymerase chain reaction (qPCR) analysis of markers of hypertrophy (FOS, calpain2 (CAPN2)), atrophy (20[Formula: see text]s proteasome alpha subunit 7 (PSMA7), cathepsin L2 (CTSL2), inflammation (Tumour necrosis factor alpha (TNF-[Formula: see text]), Interleukin-6 (IL-6)) and lipid metabolism (lipoprotein lipase, LPL and peroxisome proliferated activated receptor gamma (PPARAG). Results: 14 patients were recruited. At six weeks, no significant differences, relative to preoperative values, were noted in either objective function or leg lean mass. Markers for hypertrophy were increased (FOS [Formula: see text]1463%, [Formula: see text]), with atrophy (PSMA7 [Formula: see text]44.8%, [Formula: see text]; CTSL2 [Formula: see text]42.5%, [Formula: see text]), inflammation (TNF [Formula: see text]29.6%, [Formula: see text]) and lipid metabolism markers showing a decreasing trend (LPL [Formula: see text]42.45%, [Formula: see text]). Conclusion: The initial post-THA intramuscular environment appears supportive of anabolism. However, this is not reflected in objective function or lean mass measures at six weeks, suggesting longer duration may be required for physiological adaptation to occur.
Buckling of Beams and Columns with Defects
Authors: Lellep Jaan , Kraav Tiina
Published: September 2015

Beams and columns subjected to the axial pressure are studied. Critical buckling loads are established for stepped beams clamped at one end and elastically fixed at the other end. The beams under consideration are of piecewise constant thickness and are weakened by cracks emanating from re-entrant corners of steps. The cracks are assumed to be stable part-through surface cracks. The influence of a crack on the stability of the beam is modeled by the method of distributed line spring known in the elastic fracture mechanics. Numerical results are presented for beams with a single step making use of different stress correction functions.
Prediction of Ground Vibration from High Speed Trains Using a Vehicle–Track–Ground Coupling Model
Authors: Yao H. L. , Hu Z. , Lu Z. , Zhan Y. X. , Liu J.
Published: September 2015

The dynamically induced ground vibration from high speed trains (HSTs) is investigated using a semi-analytical vehicle–track–ground coupling model. A multi-body vehicle is adopted along with rail irregularity considered in the model. The soil is simulated as a saturated poroelastic half-space with two elastic layers. The coupling system is solved in the transformed domain by applying the Fourier transform, and the dynamic stiffness matrix method is used to deal with the layered soil. The time-domain solutions are obtained by the inverse fast Fourier transform (FFT). The effects of the vehicle speed, observation location, rail irregularity, subgrade-bed stiffness, and vehicle type on the ground vibration are investigated thoroughly. The results show that all these factors can significantly affect the dynamically induced ground vibration.
Passive Acoustic Recognition of Fishing Vessel Activity in the Shallow Waters of the Arabian Sea: A Statistical Approach
Authors: Kannan R. , Sanjana M. C. , Latha G.
Published: September 2015

The ambient noise system consisting of a vertical linear hydrophone array (VLA) with 12 elements was deployed in the waters of the Arabian Sea at a depth of 16[Formula: see text]m, off Goa, India, for extracting the ambient noise during the fishing season (March, April and May, 2013 before the onset of the south west monsoon). This study focuses on fishing vessel activity by finding the domination of the vessel and wind noise at two 12 hourly periodic cycles that start at midnight and noon, using the statistical analysis. It is performed using statistical parameters, like the mean, median, and standard deviation, skewness, percentile and spread of data. It is observed that the vessel noise dominates during the 12[Formula: see text]h period that starts at midnight and is an indication of the activity of fishing vessels while the wind generated noise is more during the 12[Formula: see text]h period that starts at noon, which is a sign of the domination of the sea breeze effects. This is the first time that a statistical analysis has been carried out to study the ambient noise data collected off Goa, in order to find the fishing vessel activity during the pre-monsoon season. The results are verified with the fishing information from the Directorate of Fisheries, Goa, ship traffic data from the Mormugao Port Trust and wind speed measurements.
Usage and Applications of Knowledge Management for Improving Library and Information Services in Bangladesh
Authors: Islam Md. Shiful , Siddike Md. Abul Kalam , Nowrin Shohana , Naznin Sonia
Published: September 2015

The aim of this paper is to explore the use and applications of Knowledge Management (KM) for improving Library and Information Services (LIS) in Bangladesh. This paper seeks to address the following research questions: How KM can be used efficiently in the libraries of Bangladesh for the improvement of LIS performance? What KM tools and techniques are being used in the libraries of Bangladesh? What difficulties are faced by the information professionals for applying KM tools and techniques in the libraries of Bangladesh? What are likely to be the means or ways to overcome those difficulties? The methodology includes a combination of both quantitative and qualitative approaches. An in-depth interview method has been used to collect data using a semi-structured questionnaire consisting of open-ended and close-ended questions. The results of this study show that document management is the highly used KM tool used in the libraries of Bangladesh followed by intranet, telephones, instant messenger, groupware, digital warehouse, and web conferencing. Results also reveal that the use and application of KM in LIS supports improved access to information resources and services, enriched professional knowledge of information professionals, enhanced environment and culture of knowledge sharing, and changed work behaviour of information professionals. The study identifies that lack of awareness about KM, lack of skilled manpower, communication gap and lack of knowledge sharing, and lack of technological infrastructure are the main problems for the use and application of KM. Finally, this study suggests that creating awareness about KM, trained and skilled manpower, reducing communication gap and improved knowledge sharing, technological and knowledge infrastructure, and the use of KM system/tools are the possible ways to overcome the problems for the use and application of KM in the libraries of Bangladesh.
On wavelet induced isomorphisms for joint (d, -d)-dilation wavelet and multiwavelet sets
Authors: Singh Pooja , Masood Dania
Published: September 2015

For a dyadic wavelet set W, Ionascu [A new construction of wavelet sets, Real Anal. Exchange28 (2002) 593–610] obtained a measurable self-bijection on the interval [0, 1), called the wavelet induced isomorphism of [0, 1), denoted by [Formula: see text]. Extending the result for a d-dilation wavelet set, we characterize a joint (d, -d)-dilation wavelet set, where |d| is an integer greater than 1, in terms of wavelet induced isomorphisms. Its analogue for a joint (d, -d)-dilation multiwavelet set has also been provided. In addition, denoting by [Formula: see text], the wavelet induced isomorphism associated with a d-dilation wavelet set W, we show that for a joint (d, -d)-dilation wavelet set W, the measures of the fixed point sets of [Formula: see text] and [Formula: see text] are equal almost everywhere.
Synthesis, photophysical characterization, and photoelectrochemical evaluation of a palladium porphyrin sensitizer for TiO2-based dye-sensitized solar cells
Authors: Berhe Seare A. , Molinets Zachary B. , Frodeman Maya N. , Miller Blair , Nesterov Vladimir N. , Haynes Keith M. , Perry Collin M. , Rodriguez Marco T. , McDougald Roy N. , Youngblood W. Justin
Published: September 2015

An unsymmetrical (A3B) palladium porphyrin bearing a cyanoacrylic acid at one meso position has been synthesized for evaluation as a photosensitizer in dye-sensitized solar cells based on titanium dioxide ( TiO 2) as a comparison to other metalloporphyrins and as a proxy for other potential triplet-state photosensitizer compounds. The synthesis of this palladium porphyrin has provided new insight into the mechanism and product distribution of decarboxylative hydrolysis of malonic acid when attached at the porphyrin meso position. A crystal structure determination for a meso-formyl palladium porphyrin has been determined, showing saddle-distortion of the porphyrin core. The photophysical behavior of the palladium porphyrin sensitizer and its performance in photoelectrochemical cells are described and interpreted in the context of bimolecular excited state quenching pathways including oxygen sensitization, triplet–triplet annihilation and electron transfer events. Palladium porphyrins are proposed as a sensitizer class with potential for high efficiency dye-sensitized solar cells, but with the caveat that some overpotential for electron injection is necessary to compete against the multiple decay pathways that are specially available to triplet state photosensitizers.
Synthesis, DNA photocleavage, singlet oxygen photogeneration and two photon absorption properties of ruthenium-phenanthroline porphyrins
Authors: Xu Ze-Bin , Yu Fa-Quan , Wu Fengshou , Zhang Heng , Wang Kai , Zhang Xiu-Lan
Published: September 2015

Through a new synthetic route, three ruthenium-phenanthroline porphyrins (RPP1, RPP2 and RPP3) were prepared. Their photophysical and photochemical properties, such as DNA photocleavage activity, singlet-oxygen photogeneration and two-photon absorption (2PA) were evaluated. These porphyrins 1–3 had substantial photocleavage activities, with 71%, 74% and 38% observed at 20 μM. The porphyrins with different substituents on phenathroline group had similar singlet oxygen quantum yields, with ΦΔ values at 0.52, 0.47 and 0.41, respectively. The 2PA cross-section (σ(2)) values of RPP 1–3, measured by the Z-scan method, were calculated to be 152, 172 and 135 GM, respectively, which were around 5-fold higher than that of H2TPP . Thus, these porphyrins, with their good photocleavage activities, 1 O 2 quantum yields and high 2PA cross section, suggest great potential as photodynamic therapeutic agents.
The coulometric approach to the superoxide scavenging activity determination: The case of porphyrin derivatives influence on oxygen electroreduction
Authors: Kuzmin Sergey M. , Chulovskaya Svetlana A. , Parfenyuk Vladimir I.
Published: September 2015

The electrochemical and antioxidant properties of 5,10,15,20-tetrakis(3′-hydroxyphenyl)porphyrin ( H 2 T (m- OHPh ) P ) and 5,10,15,20-tetrakis(4′-hydroxyphenyl)porphyrin ( H 2 T (p- OHPh ) P ) were tested by the cyclic voltammetry (CV) method. It is shown that in dimethylsulfoxide (DMSO) the electroreduction processes of oxygen and porphyrins are under diffusion control. The electroreduction of H 2 T (m- OHPh ) P and H 2 T (p- OHPh ) P with potentials about -1 V are irreversible due to the chemical step (EC process) which leads to products with oxidation potentials about -0.5 V. Additionally in case of oxygen and porphyrin coreduction, both H 2 T (m- OHPh ) P and H 2 T (p- OHPh ) P influence the O 2•- electrosynthesis. The nonlinear dependence of the O 2•- peak current vs. porphyrin concentrations makes the available amperometric approach unsuitable for antioxidant activity estimation. To solve this problem, the coulometric parameters were calculated. The excellent linearity of the coulometric response of superoxide ion vs. porphyrins concentration was demonstrated for a wide concentration range. On the basis of coulometric responses, we constructed a parameter which separated the radical scavenging activity and variation of oxygen electroreduction. The superoxide scavenging activities of H 2 T (m- OHPh ) P and H 2 T (p- OHPh ) P were determined using the developed approach. The effect of OH group position on the superoxide scavenge activity is shown: H 2 T (p- OHPh ) P has a higher activity (slope = 0.75 L.mmol-1) than H 2 T (m- OHPh ) P (slope = 0.60 L.mmol-1).
The effect of substitutents at alkylsulfanyl/arylsulfanyl non-peripherally substituted phthalocyanines: Spectral and photophysical properties, basicity and photostability
Authors: Cidlina Antonin , Pausimova Zuzana , Miletin Miroslav , Zimcik Petr , Novakova Veronika
Published: September 2015

A series of magnesium, zinc and metal-free derivatives of non-peripherally substituted phthalocyanines (Pcs) bearing alkylsulfanyl or arylsulfanyl groups of different bulkiness was synthesized. Their spectral and photophysical properties including also the basicity of azomethine nitrogens and photostability were compared within the series as well as with similar peripherally substituted Pcs. Non-peripheral position of substituents led to the 70[Formula: see text]nm red-shift of Q-band in comparison to the peripherally substituted Pcs. However, unexpected blue-shift of approximately 50[Formula: see text]nm was observed in the series of non-peripherally substituted Pcs for the most bulky tert-butylsulfanyl derivative caused probably by extreme distortion of the macrocycle. The substitution had no effect on photophysical properties and compounds reached [Formula: see text] values 0.74–0.76 and [Formula: see text] 0.053–0.080 for zinc complexes, and [Formula: see text] 0.47–0.51 and [Formula: see text] 0.10–0.17 for magnesium complexes following the rule of heavy atom effect. Generally, non-peripherally substituted Pcs possessed improved singlet oxygen production in comparison to peripherally substituted ones. The photostability of the target compounds decreased with the red-shift of their absorption maxima with the arylsulfanyl derivatives being less photostable. The basicity of azomethine nitrogens was clearly dependent on the position and the character of substituent. Thus, non-peripherally substituted Pcs showed extraordinary increased basicity over the peripherally substituted ones with the most pronounced effect at alkylsulfanyl derivatives.
Novel Strategy to Improve the Performance of Localization in WSN
Authors: Vasim Babu M. , Ramprasad A. V.
Published: September 2015

A novel strategy of discrete energy consumption model for WSN based on quasi Monte Carlo and crude Monte Carlo method is developed. In our model the discrete hidden Markov process plays a major role in analyzing the node location in heterogeneous media. In this energy consumption model we use both static and dynamic sensor nodes to monitor the optimized energy of all sensor nodes in which every sensor state can be considered as the dynamic Bayesian network. By using this method the power is assigned in terms of dynamic manner to each sensor over discrete time steps to control the graphical structure of our network. The simulation and experiment result shows that our proposed methods are better in terms of localization accuracy and possess minimum computational time over existing localization method.
Primary Chronic Osteomyelitis of the Jaws in Children: An Update on Pathophysiology, Radiological Findings, Treatment Strategies, and Prospective Analysis of Two Cases
Authors: Berglund Caroline , Ekströmer Karin , Abtahi Jahan
Published: September 2015

Objective.Primary chronic osteomyelitis (PCO) of the jaws in children is associated with pain, trismus, and swelling. In children, temporomandibular joint involvement is rare and few studies have been published due to the relatively low incidence. This paper presents two cases of mandibular PCO in children with the involvement of the collum mandibulae. In addition, a review of the literature regarding demographic data, histological, radiological, and laboratory findings, and treatment strategies of PCO was also performed.Material and Methods.Prospective analyses of two PCO cases. A PubMed search was used and the articles were sorted according to their corresponding key area of focus.Results.Review of the literature revealed twenty-four cases of PCO with two cases of mandibular condyle involvement. The mean age was 18 years; the male to female ratio was 1 : 3. Most of the patients were treated with anti-inflammatory drugs in combination with decortication. Clinical recurrence was seen in 7 cases.Conclusion.A combination of anti-inflammatory drugs and surgical intervention appears to be the first choice of treatment. However, surgical removal of necrotic tissue adjacent to collum mandibulae has its limitations in children. Further investigations are of utmost importance in order to increase our knowledge and understanding of this disease.
A Report of Accelerated Coronary Artery Disease Associated with Cerebral Autosomal Dominant Arteriopathy with Subcortical Infarcts and Leukoencephalopathy
Authors: Rubin Courtney B. , Hahn Virginia , Kobayashi Taisei , Litwack Andrew
Published: September 2015

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is the most common heritable form of vascular dementia and it is caused by mutations in theNOTCH3gene. The neurologic manifestations of CADASIL syndrome have been well characterized; however, here we report one of the firstde novocases of CADASIL-associated coronary artery disease. A 45-year-old woman with a history of CADASIL and remote tobacco use presented with unstable angina. She was found to have diffuse and irregular narrowing of the left anterior descending artery and a drug eluting stent was deployed. Months later, she developed two subsequent episodes of unstable angina, requiring stent placement in the distal left anterior descending artery and the right coronary artery. Though the neurologic manifestations of CADASIL have been well described, these patients may also be predisposed to developing premature coronary artery disease. Patients with CADASIL and their physicians should be aware of this possible association because these patients may not be identified as high risk by traditional cardiovascular risk estimators. These patients may benefit from more aggressive interventions to reduce cardiac risk.
Missense Mutations in Exons 18–24 of EGFR in Hepatocellular Carcinoma Tissues
Authors: Panvichian Ravat , Tantiwetrueangdet Anchalee , Sornmayura Pattana , Leelaudomlipi Surasak
Published: September 2015

Epidermal growth factor receptor (EGFR), a transmembrane tyrosine kinase receptor, plays important roles in various cancers. In nonsmall cell lung cancer (NSCLC), EGFR mutations cluster around the ATP-binding pocket (exons 18–21) and some of these mutations activate the kinase and induce an increased sensitivity to EGFR-tyrosine kinase inhibitors. Nevertheless, data of EGFR mutations in HCC are limited. In this study, we investigated EGFR expression by immunohistochemistry and EGFR mutations (exons 18–24) by PCR cloning and sequencing. EGFR overexpression in HCC and matched nontumor tissues were detected in 13/40 (32.5%) and 10/35 (28.6%), respectively. Moreover, missense and silent mutations were detected in 13/33 (39.4%) and 11/33 (33.3%) of HCC tissues, respectively. The thirteen different missense mutations were p.L730P, p.V742I, p.K757E, p.I780T, p.N808S, p.R831C, p.V851A, p.V897A, p.S912P, p.P937L, p.T940A, p.M947V, and p.M947T. We also found already known SNP, p.Q787Q (CAG>CAA), in 13/33 (39.4%) of HCC tissues. However, no significant association was detected between EGFR mutations and EGFR overexpression, tissue, age, sex, tumor size, AFP, HBsAg, TP53, and Ki-67. Further investigation is warranted to validate the frequency and activity of these missense mutations, as well as their roles in HCC tumorigenesis and in EGFR-targeted therapy.
An Automatic Detection Method of Nanocomposite Film Element Based on GLCM and Adaboost M1
Authors: Guo Hai , Yin Jinghua , Zhao Jingying , Liu Yuanyuan , Yao Lei , Xia Xu
Published: September 2015

An automatic detection model adopting pattern recognition technology is proposed in this paper; it can realize the measurement to the element of nanocomposite film. The features of gray level cooccurrence matrix (GLCM) can be extracted from different types of surface morphology images of film; after that, the dimension reduction of film can be handled by principal component analysis (PCA). So it is possible to identify the element of film according to the Adaboost M1 algorithm of a strong classifier with ten decision tree classifiers. The experimental result shows that this model is superior to the ones of SVM (support vector machine), NN and BayesNet. The method proposed can be widely applied to the automatic detection of not only nanocomposite film element but also other nanocomposite material elements.
TDOA-Based Source Collaborative Localization via Semidefinite Relaxation in Sensor Networks
Authors: Yan Yongsheng , Wang Haiyan , Shen Xiaohong , He Ke , Zhong Xionghu
Published: September 2015

The time delay of arrival- (TDOA-) based source localization using a wireless sensor network has been considered in this paper. The maximum likelihood estimate (MLE) is formulated by taking the correlated TDOA noise into account, which is caused by the difference with the TOA of the reference sensor. The global optimal solution is difficult to obtain due to the nonconvex nature of the ML function. We propose an alternative semidefinite programming method, which transforms the original ML problem into a convex one by relaxing nonconvex equalities into convex matrix inequalities. In addition, the source localization algorithm in the presence of sensor location errors and non-line-of-sight (NLOS) observations is developed. Our simulation results demonstrate the potential advantages of the proposed method. Furthermore, the proposed source localization algorithm by taking the NLOS TOA measurements as the constraints of the convex problem can provide a good estimate.
Integrated Control of Hydromechanical Variable Transmissions
Authors: Yang Shujun , Bao Yong , Tang Xianzhi , Jiao Xiaojuan , Yang Deqing , Wang Qing
Published: September 2015

A hydromechanical variable transmission (HMT) has advantages of continuous variation and high efficiency. So it is one of the ideal transmissions of heavy vehicles. The continuous speed varying process involves speed governing in range and range shift. Integrated control strategy of the HMT is proposed in this paper. The algorithm of the asymmetric saturated incremental proportional integral derivative (PID) speed control strategy in range and range shift conditions are derived. And this paper presents the range shift logic and range shift control strategies. A controller model is built in Matlab Simulink and cosimulated with the model of vehicle equipped with a two-range HMT. The HMT prototype hardware-in-the-loop simulation (HILS) platform of the integrated control strategy is built. The HILS results show that the range shift process is smooth and speed fluctuation does not happen. In the throttle stable stage, the engine speed is adjusted to the near optimal speed, and its change rules are in accordance with simulation results. The integrated control strategy is reasonable.
The Chondroprotective Role of TMF in PGE2-Induced Apoptosis Associating with Endoplasmic Reticulum Stress
Authors: Yang Jianqiong , Liu Haiqing , Li Linfu , Liu Hai , Shi Weimei , Wu Longhuo
Published: September 2015

Endoplasmic reticulum stress (ERS) has been demonstrated to exhibit a critical role in osteoarthritic chondrocytes. Whether 5,7,3′,4′-tetramethoxyflavone (TMF) plays the chondroprotective role in inhibition of PGE2-induced chondrocytes apoptosis associating with ERS has not been reported. To investigate this, the activation of PERK, ATF6, and IRE1 signaling pathways in ERS in chondrocytes pretreated with PGE2was studied. By treatment with PGE2, the chondrocytes apoptosis was significantly increased, the proapoptotic CHOP and JNK were upregulated, the prosurvival GRP78 and XBP1 were downregulated, and GSK-3βwas also upregulated. However, TMF exhibited the effectively protective functions via counteracting these detrimental effects of PGE2. Finally, the inflammatory cytokine PGE2can activate ERS signaling and promote chondrocytes apoptosis, which might be associated with upregulation of GSK-3β. TMF exhibits a chondroprotective role in inhibiting PGE2-induced ERS and GSK-3β.
Prevalence and Pattern of Soil-Transmitted Helminthic Infection among Primary School Children in a Rural Community in Imo State, Nigeria
Authors: Odinaka Kelechi Kenneth , Nwolisa Emeka Charles , Mbanefo Francis , Iheakaram Alfreda Chinekwu , Okolo Seline
Published: September 2015

Background.Soil-transmitted helminthic infection is a common public health challenge of primary school children in resource challenged and developing countries. Our aim was to determine the prevalence and pattern of soil-transmitted helminthic infection among primary school children in a rural community in Imo State, Nigeria.Method.The study involved a cross-sectional survey of 284 primary school children in a rural community.Results.The overall prevalence of soil-transmitted helminthic infection (STHI) was 30.3%. Of all STHIs, hookworm was the commonest geohelminth observed, 81 (94.2%). The prevalence of soil-transmitted helminthic infection was more in males, 58 (38.4%), than in females, 28 (21.1%). This difference was statistically significant (P=0.001).Conclusion.The high prevalence rate of soil-transmitted helminthic infection amongst the study population is worrisome. There is need for organized and routine deworming among school children in the community.
Estimation Method of Path-Selecting Proportion for Urban Rail Transit Based on AFC Data
Authors: Zhou Feng , Shi Jun-gang , Xu Rui-hua
Published: September 2015

With the successful application of automatic fare collection (AFC) system in urban rail transit (URT), the information of passengers’ travel time is recorded, which provides the possibility to analyze passengers’ path-selecting by AFC data. In this paper, the distribution characteristics of the components of travel time were analyzed, and an estimation method of path-selecting proportion was proposed. This method made use of single path ODs’ travel time data from AFC system to estimate the distribution parameters of the components of travel time, mainly including entry walking time (ewt), exit walking time (exwt), and transfer walking time (twt). Then, for multipath ODs, the distribution of each path’s travel time could be calculated under the condition of its components’ distributions known. After that, each path’s path-selecting proportion can be estimated. Finally, simulation experiments were designed to verify the estimation method, and the results show that the error rate is less than 2%. Compared with the traditional models of flow assignment, the estimation method can reduce the cost of artificial survey significantly and provide a new way to calculate the path-selecting proportion for URT.
Melatonin and Ischemic Stroke: Mechanistic Roles and Action
Authors: Andrabi Syed Suhail , Parvez Suhel , Tabassum Heena
Published: September 2015

Stroke is one of the most devastating neurological disabilities and brain’s vulnerability towards it proves to be fatal and socio-economic loss of millions of people worldwide. Ischemic stroke remains at the center stage of it, because of its prevalence amongst the several other types attacking the brain. The various cascades of events that have been associated with stroke involve oxidative stress, excitotoxicity, mitochondrial dysfunction, upregulation of Ca2+level, and so forth. Melatonin is a neurohormone secreted by pineal and extra pineal tissues responsible for various physiological processes like sleep and mood behaviour. Melatonin has been implicated in various neurological diseases because of its antioxidative, antiapoptotic, and anti-inflammatory properties. We have previously reviewed the neuroprotective effect of melatonin in various models of brain injury like traumatic brain injury and spinal cord injury. In this review, we have put together the various causes and consequence of stroke and protective role of melatonin in ischemic stroke.
Stochastic Computer Simulation of Cermet Coatings Formation
Authors: Solonenko Oleg P. , Jordan Vladimir I. , Blednov Vitaly A.
Published: September 2015

An approach to the modeling of the process of the formation of thermal coatings lamellar structure, including plasma coatings, at the spraying of cermet powders is proposed. The approach based on the theoretical fundamentals developed which could be used for rapid and sufficiently accurate prediction of thickness and diameter of cermet splats as well as temperature at interface “flattening quasi-liquid cermet particle-substrate” depending on the key physical parameters (KPPs): temperature, velocity and size of particle, substrate temperature, and concentration of finely dispersed solid inclusions uniformly distributed in liquid metal binder. The results are presented, which concern the development of the computational algorithm and the program complex for modeling the process of laying the splats in the coating with regard to the topology of its surface, which varies dynamically at the spraying, as well as the formation of lamellar structure and porosity of the coating. The results of numerical experiments are presented through the example of thermal spraying the cermet TiC-30 vol.% NiCr powder, illustrating the performance of the developed computational technology.
Design of Multiregional Supervisory Fuzzy PID Control of pH Reactors
Authors: AlSabbah Shebel , AlDhaifallah Mujahed , Al-Jarrah Mohammad
Published: September 2015

This work concerns designing multiregional supervisory fuzzy PID (Proportional-Integral-Derivative) control for pH reactors. The proposed work focuses, mainly, on two themes. The first one is to propose a multiregional supervisory fuzzy-based cascade control structure. It would enable modifying dynamics and enhance system’s stability. The fuzzy system (master loop) has been chosen as a tuner for PID controller (slave loop). It takes into consideration parameters uncertainties and reference tracking. The second theme concerns designing a hybrid neural network-based pH estimator. The proposed estimator would overcome the industrial drawbacks, that is, cost and size, found with conventional methods for pH measurement. The final end-user-interface (EUI) front panel and the results that evaluate the performance of the supervisory fuzzy PID-based control system and hybrid NN-based estimator have been presented using the compatibility found between LabView and MatLab. They lead to conclude that the proposed algorithms are appropriate to systems nonlinearities encountered with pH reactors.
Additional Riderships Estimation under Different Configurations of Bus Rapid Transit System
Authors: Lan Wu , Xuewu Chen , Tao Lu
Published: September 2015

Different configurations of Bus Rapid Transit (BRT) system may cause different additional riderships. In this paper, in terms of network traffic equilibrium assignment principle, the additional riderships estimation model based on Variational Inequality (VI) model is presented. The bus frequency is related to variables including the travel time, the residence time in terminals, and the dwelling time at the stops. The additional riderships are translated into network additional traffic flow firstly. Given the bus frequency, VI model can be turned into Stochastic User Equilibrium (SUE) model to calculate the other variables. The similarity diagonalization method is used to calculate the elastic bus frequency and finally the network additional traffic flow can be computed. The additional riderships under different configurations of BRT system are compared in the numerical test. The results show that the additional riderships under different configurations have large differences and occupy a high percentage of the total ridership.
Generation Control of ZnO Nanoparticles Using a Coaxial Gas-Flow Pulse Plasma Ar/O2 Plasma
Authors: Shirahata Hiroki , Iizuka Satoru
Published: September 2015

Generation of ZnO nanoparticles was investigated using a coaxial gas-flow pulse plasma. We studied how zinc atoms, sputtered from a zinc target, reacted with oxygen in a plasma and/or on a substrate to form ZnO nanoparticles when the discharge parameters, such as applied pulse voltage and gas flow rate, were controlled in an O2/Ar plasma. The formation processes were estimated by SEM, TEM, and EDX. We observed many ZnO nanoparticles deposited on Si substrate. The particle yield and size were found to be controlled by changing the experimental parameters. The diameter of the particles was typically 50–200 nm.
The Study of Thermal Conditions on Weibel Instability
Authors: Mahdavi M. , Khanzadeh H.
Published: September 2015

Weibel electromagnetic instability has been studied analytically in relativistic plasma with high parallel temperature, where|α=(mc2/T∥)(1+p^⊥2/m2c2)1/2|≪1and while the collision effects of electron-ion scattering have also been considered. According to these conditions, an analytical expression is derived for the growth rate of the Weibel instability for a limiting case of|ζ=α/2(ω′/ck)|≪1, whereω′is the sum of the wave frequency of instability and the collision frequency of electrons with background ions. The results show that in the limiting conditionα≪1there is an unusual situation of the Weibel instability so thatT∥≫T⊥, while in the classic Weibel instabilityT∥≪T⊥. The obtained results show that the growth rate of the Weibel instability will be decreased due to an increase in the number of collisions and a decrease in the anisotropic temperature by the increasing of plasma density, while the increase of the parameterγ^⊥=(1+p^⊥2/m2c2)1/2leads to the increase of the Weibel instability growth rate.