bluuebunny/crossref_metadata_2025_split huggingface dataset:
Helicopter Health Monitoring From Engine to Rotor
Authors: Marriott J. F. , Kaye J. F. M. 
Published: March 2015

Recent tragic accidents have focused attention on the dangers of unmonitored helicopter dynamic assemblies. Methods are available to monitor the entire power train from the engine to the rotor. Apart from the obvious safety advantages, such systems offer the additional benefits of increased availability, a planned maintenance schedule and a reduction in life cycle costs.
Historically, monitoring systems have evolved from isolated processing units, each performing single functions. Hawker Siddeley Dynamics Engineering Ltd, in conjunction with Stewart Hughes Ltd is developing a modular and integrated health and usage monitoring system. After a brief discussion of health monitoring equipment evolution, this paper focuses on the practical application of the techniques required to ensure the health of the modern helicopter.
High Operation Flexibility and Reliability by Multi-Unit Compressor Arrangement for Gas Storage Applications
Authors: Neuburg Harald , Schmidt Klaus D. 
Published: March 2015

The growing gas market and the increasing ratio of imported gas to gas produced within a country requires an expanded capacity for buffer gas storage to compensate for differences between constant import gas flow and seasonal variances in consumption.
For economical operation of the gas storage facility and for moving extensive quantities of gas, high operating flexibility as well as high availability and reliability of gas compression equipment are required.
This paper will report on an underground gas storage project and indicate specific objectives for the project in reservoir engineering, gas compression and free-flow withdrawal duties. It will also deal with the sizing and selection of gas turbine driven centrifugal compressor sets, including the required station equipment.
Finally, operating experience will be discussed.
Real Time Simulators for Use in Design of Integrated Flight and Propulsion Control Systems
Authors: Davies William J. , Jones Charlie L. , Noonan Robert A. 
Published: March 2015

The introduction of Full Authority Digital Electronic Controls (FADEC) to both commercial and military aircraft gas turbine engines provides significant operational benefits. FADEC’s are reliable and more maintainable than the hydromechanical controls they have replaced. The next significant change in their use will be integration with the flight control, particularly in military applications, to provide reduced fuel consumption in cruise and rapid, accurate engine transients for increased maneuverability.
Integration with the flight control system requires another level of control system testing beyond verification that the FADEC will perform it’s principle functions-control and protection of the engine. This new testing requires that the FADEC be tested in unison with the flight control to verify total control system capability and safety throughout the flight envelope. These testing requirements have been addressed at Pratt & Whitney and various airframers through application of the same simulation tools which have been in use to verify FADEC hardware and software capability prior to engine test. These test systems and their application to advanced integrated control systems are described herein to provide insight into both their operation and application.
Recent Advances in Engine Health Management
Authors: Pipe Kenneth , Fisher Celia 
Published: March 2015

New measurement capabilities developed in the last five years have greatly enhanced the ability of monitoring systems to produce acceptable engine distress and maintenance information to pilots.
The more recent advances are particularly useful for military and helicopter engines. This paper describes three new techniques, with descriptions of their application. These include direct aerodynamic thrust measurement, gas path distress analysis and analysis of the dynamic behaviour of gas turbines. The paper concludes by suggesting the impact of these techniques on systems design for future engines.
A New Source of Lightweight, Compact Multifuel Power for Vehicular, Light Aircraft and Auxiliary Applications: The Joint Deere Score™ Engines
Authors: Jones Charles 
Published: March 2015

Deere & Co. has actively pursued development of the multifuel Wankel-type stratified charge engine since February 1984. During this period, a new R&D facility has been established where development is in progress for three new engine families having basic displacements of .66, 1.72 and 5.8 liters/rotor, for a 1 to 8 rotor engine output range from 37 to 2250kW (50 to 3000HP). The initial SCORE™ (“Stratified Charge Omniverous Rotary Engines”) production engines will be placed into service next year. This series of three engine families offers the size, weight and low vibration characteristics of small gas turbines and the fuel efficiency and initial cost characteristics of diesel engines.
This paper describes the combustion concept, relates relevant history and gives the current development status for all three basic sizes.
Pre-Swirl Blade-Cooling Effectiveness in an Adiabatic Rotor-Stator System
Authors: El-Oun Z. B. , Owen J. M. 
Published: March 2015

Blade-cooling air for a high-pressure turbine is often supplied from pre-swirl nozzles attached to a stationary casing. By swirling the cooling air in the direction of rotation of the turbine disc, the temperature of the air relative to the blades can be reduced. The question addressed in this paper is: knowing the temperatures of the pre-swirl and disc-cooling flows, what is the temperature of the blade-cooling air?
A simple theoretical model, based on the Reynolds analogy applied to an adiabatic rotor-stator system, is used to calculate the pre-swirl effectiveness (that is, the reduction in the temperature of the blade-cooling air as a result of pre-swirling the flow). A mixing model is used to account for the ‘contamination’ of the blade-coolant with disc-cooling air, and an approximate solution is used to estimate the effect of frictional heating on the disc-cooling air.
Experiments were conducted in a rotor-stator rig which had pre-swirl nozzles in the stator and blade-cooling passages in the rotating disc. A radial outflow or inflow of disc-cooling air was also supplied, and measurements of the temperature difference between the pre-swirl and blade-cooling air were made for a range of flow rates and for rotational Reynolds numbers up to Reθ = 1.8 × 106. Considering the experimental errors in measuring the small temperature differences, good agreement between theory and experiment was achieved.
Material Property Measurements on Thermal Barrier Coatings
Authors: Berndt Christopher C. 
Published: March 2015

The material property measurements of thermal barrier coatings from cyclic furnace, thermal rig, thermal expansion, acoustic emission and tensile adhesion test methods are critically examined. Some basic engineering properties of coatings such as the elastic modulus have not been measured without ambiguity. Data of this nature is essential to the success of modeling studies.
Insights into the mechanical properties of coatings have been gained by carrying out instrumented tensile adhesion tests. The general view of the coating deformation process is that the individual lamellae slide over each other and this promotes a “pseudo-ductility” response in the coating. Monitoring of the acoustic emission response of coatings during thermal cycling experiments suggests that there are two distinct cracking processes. The macro-cracking behaviour, indicated by a change in the acoustic emission count rate, is the predominant mechanism which leads to coating failure.
It is further shown that the acceptance tests used by industry, although useful in ranking coatings in terms of a particular property, present no fundamental knowledge concerning the material properties of coatings. It is only when the phenomenological characteristics of the thermo-mechanical response of coatings is understood that coating development will substantially progress.
Teaming: A Case Study
Authors: White Steven D. , Wolfe Robert A. 
Published: March 2015

Textron Lycoming and Pratt&Whitney teamed to develop the T800 for the Army’s LHX program and other applications. A teamed approach was selected in order to answer the Army’s requirement for true competition during the production phase of the program. Clear definition of this requirement, while not specifying teaming as absolutely necessary, was a critical element in the rapid and smooth initiation of the teamed effort. Additional key elements were management compatibility, equal technical contribution, willingness to transfer technology, and team focus on a clear goal.
An organization was structured which utilizes a Joint Program Office (JPO) as the managing unit. This office is located at Stratford, Connecticut, and is staffed by Textron Lycoming and Pratt&Whitney personnel. The JPO structure has been successful in forcing the joint decision process to function within both organizations. This case study focuses on the process of teaming for the development of complex systems. It addresses initiation of the team, management structure, unique management issues, benefits to participants and customers, and lessons learned.
Austenitic High-Performance Materials for Non-Rotating Components in Stationary Gas Turbines
Authors: Drefahl K. , Hofmann Franz 
Published: March 2015

Five essential requirements for gas turbine materials exposed to high temperatures are discussed:
- High resistance to oxidation and high temperature corrosion
- High creep strength especially under condition of thermal stress
- High fatigue strength under conditions of vibrational and thermal stress
- Good workability since complicated deformation and machining processes are often necessary
- Good weldability
It is not always possible to make all these requirements totally compatible. This is because certain requirements have to be emphasized for reasons of application. In most cases compromises will have to be made in regard to workability.
Experience With Supplementary Combustion Systems to Maximize Steam Production in Gas Turbine Cogeneration Plants
Authors: Backlund J. C. , Fiorenza E. E. 
Published: March 2015

Topping cycle cogeneration plants, consisting of a relatively small gas turbine generator (3–5 MW) and a supplementary fired heat recovery steam generator designed to maximize steam production, are becoming a very attractive system design. Special burners designed to fire into water wall furnaces can add substantial steam production capability to the system in a very efficient manner, utilizing the oxygen available in the turbine exhaust.
This paper examines recent operating experience at two U.S. installations, using gas turbines rated at 3.3 MW (Iso) and 4. 8 MW (Iso). Gas fired burner designs are presented. Performance parameters such as response to load, maximum steam production, burner rangeability, and emissions of NOx and CO are discussed.
The PGT 10 Heavy Duty 10 MW Gas Turbine
Authors: Gusso R. , Benvenuti E. , Bianchi D. , Sabella D. 
Published: March 2015

The PGT 10 two-shaft, 10 MW, industrial gas turbine has a capability of up to 34% simple-cycle efficiency, high reliability with extended range of operation and low exhaust emissions. Features like the 14:1 pressure ratio and high specific mass flow transonic axial compressor are at the highest levels in the heavy-duty gas turbine design. The firing temperature, the blade cooling techniques, the extended modularization of components and subassemblies are in their turn representative of the well-proven, state-of-art technology: performance results also from the aero-thermodynamic design aimed at maximizing component efficiencies.
This paper introduces the major aspects of the PTG 10 turbine design. After full-load testing was successfully completed on the first units, the PTG 10 has entered normal production in 1987 and several units have already been installed or shipped.
Transition Modeling Effects on Viscous/Inviscid Interaction Analysis of Low Reynolds Number Airfoil Flows Involving Laminar Separation Bubbles
Authors: Walker G. J. , Subroto P. H. , Platzer M. F. 
Published: March 2015

Estimating the low Reynolds number and off-design performance of axial turbomachine blades requires an accurate prediction of separation phenomena occurring on the blade surface. This paper discusses a viscous/inviscid interaction analysis of flow over a NACA 65-213 airfoil at a chord Reynolds number of 240,000 using a calculation method of Cebeci et al. The computed characteristics of a mid-chord laminar separation bubble are compared with experimental laser-doppler anemometer measurements of Hoheisel et al. Attention is focused on problems of modeling the laminar-turbulent transition zone within the viscous layer.
A parametric study is undertaken to determine the location and extent of the transition zone which best models the observed separation bubble behavior. The required transition length is almost an order of magnitude smaller than that predicted from conventional transition length correlations. A physical model for this greatly reduced transition length in positive pressure gradient flows is proposed.
The computational model correctly predicts most features of the separation bubble flow, but there are some significant discrepancies at reattachment which point to the need for improved turbulence modeling in this area. The inclusion of transverse pressure gradients associated with flow curvature in the viscous regions also appears very desirable for airfoils operating at Reynolds numbers around 105.
Knowledge of habitat preferences applied to habitat management: the case of an endangered tortoise population
Authors: Vilardell-Bartino Albert , Vilardell-Bartino Albert , Capalleras Xavier , Vilardell-Bartino Albert , Capalleras Xavier , Budó Joan , Vilardell-Bartino Albert , Capalleras Xavier , Budó Joan , Bosch Rafel , Vilardell-Bartino Albert , Capalleras Xavier , Budó Joan , Bosch Rafel , Pons Pere 
Published: March 2015

To avoid the possible extinction of the last native population of western Hermann’s tortoise in the Iberian Peninsula it is essential to make sound management decisions. Knowledge of macro and microhabitat use and home range size has considerable practical value for land managers. With this aim we first studied the home range and habitat preferences in western Hermann’s tortoises by radio tracking 15 adults weekly from March 2008 to May 2009 in three localities within the Albera population range (NE Iberian Peninsula). We estimated home ranges with Fixed Kernel estimator (FK) and Minimum Convex Polygon (MCP) after checking tortoise site fidelity. We observed that home range size did not differ significantly between males and females (mean FK = 2.01 ha, mean MCP = 3.01 ha). Secondly, we studied macrohabitat selection using a vegetation map. Preferred habitats were open shrubland, open forest and barren land during the activity period, and dense forest, dense shrubland and open shrubland during the hibernation. Next, we assessed microhabitat selection along five periods of the annual cycle: hibernation, emergence from hibernation, spring, summer and autumn. We then located marked tortoises weekly and classified the plant species observed in each location. Principal component analyses showed that tortoises selected shrubs with trees during hibernation, bramble during summer and herbaceous habitat during the breeding season. All these results can provide guidelines for management programs that set aside areas of habitat critical to conserve viable populations, although it is also important to prevent mortality from forestry works. We therefore tested a new brush cutter head accessory to achieve tortoise-safe undergrowth clearing. To this aim we distributed 52 frozen hybrid tortoises among eight plots of 100 m2, cleared six of these plots with the accessory and two without it, and evaluated the scars of the blade on caparaces. We observed no damage in plots that were cleared with the accessory but scars in most carapaces in the plots cleared without it (with potential mortality ranging from 40% in neonates to 100% in adults). These results outline the importance of supporting habitat management decisions with proper field studies.
Reference Upper-Air Observations for Climate: From Concept to Reality
Authors: Bodeker G. E. , Bojinski S. , Cimini D. , Dirksen R. J. , Haeffelin M. , Hannigan J. W. , Hurst D. F. , Leblanc T. , Madonna F. , Maturilli M. , Mikalsen A. C. , Philipona R. , Reale T. , Seidel D. J. , Tan D. G. H. , Thorne P. W. , Vömel H. , Wang J. 
Published: March 2015

Abstract
The three main objectives of the Global Climate Observing System (GCOS) Reference Upper-Air Network (GRUAN) are to provide long-term high-quality climate records of vertical profiles of selected essential climate variables (ECVs), to constrain and calibrate data from more spatially comprehensive global networks, and to provide measurements for process studies that permit an in-depth understanding of the properties of the atmospheric column. In the five years since the first GRUAN implementation and coordination meeting and the printing of an article (Seidel et al.) in this publication, GRUAN has matured to become a functioning network that provides reference-quality observations to a community of users.
This article describes the achievements within GRUAN over the past five years toward making reference-quality observations of upper-air ECVs. Milestones in the evolution of GRUAN are emphasized, including development of rigorous criteria for site certification and assessment, the formal certification of the first GRUAN sites, salient aspects of the GRUAN manual and guide to operations, public availability of GRUAN’s first data product, outcomes of a network expansion workshop, and key results of scientific studies designed to provide a sound scientific foundation for GRUAN operations.
Two defining attributes of GRUAN are 1) that every measurement is accompanied by a traceable estimate of the measurement uncertainty and 2) that data quality and continuity are maximized because network changes are minimized and managed. This article summarizes how these imperatives are being achieved for existing and planned data products and provides an outlook for the future, including expected new data streams, network expansion, and critical needs for the ongoing success of GRUAN.
Tornado Damage Mitigation: Benefit–Cost Analysis of Enhanced Building Codes in Oklahoma
Authors: Simmons Kevin M. , Kovacs Paul , Kopp Gregory A. 
Published: March 2015

AbstractIn April 2014, the city of Moore, Oklahoma, adopted enhanced building codes designed for wind-resistant construction. This action came after Moore suffered three violent tornadoes in 14 yr. Insured loss data and a rigorous approach to estimating how much future damage can be mitigated is used to conduct a benefit–cost analysis of the Moore standards applied to the entire state of Oklahoma. The results show that the new codes easily pass the benefit–cost test for the state of Oklahoma by a factor of 3 to 1. Additionally, a sensitivity analysis is conducted on each of the five input variables to identify the threshold where each variable causes the benefit–cost test to fail. Variables include the estimate of future losses, percent of damage that can be reduced, added cost, residential share of overall losses, and the discount rate.
Adolescents’ Health Education and Social Media
Authors: Singh Rashmi , Nayak J.K. 
Published: March 2015

Purpose: The research aims to predict the perceptions/opinion of nutritious/harmful intake and the perceptions/opinion of different socializing agents who encouraged nutritious and healthy eating among the Indian adolescents. Design/Methodology/Approach: A survey was done on 160 adolescents from the different zones (eastern, western, northern, southern) in India. A well-structured questionnaire with suitable items was prepared and distributed among the adolescents in India. Findings: The findings of this study reveal that adolescents frequently ate/consumed unhealthy and junk foods (chocolates, snacks, soft drinks, etc.). As per the adolescents’ perception, the intake of foods regularly on time comes under the most important healthy eating habit. Also, as far as the situational influences are concerned, like in marriages/birthday parties, it has been found that adolescents generally eat unhealthy foods. While at home or when they are sick, they generally eat healthy and nutritious food. The socializing agents, especially parents, act as a main agent or promoter for the healthy food as compared to peers, schools or the siblings. Research Limitations/Implications: In each region (east, west, north, south), only two to three secondary schools were chosen for the data collection; all these schools could not be the representative of the all the adolescents in different regions. Originality/Value: The article offers insights into designing communication strategies for adolescents’ health education. It is original in that it focuses on adolescents, and explores the perceptions of different socializing agents and the influence of advertising media appeals on healthy eating.
Interaction between mesenchymal stem cells and endothelial cells restores endothelial permeability via paracrine hepatocyte growth factor in vitro
Authors: Chen Qi-Hong , Liu Ai-Ran , Qiu Hai-Bo , Yang Yi 
Published: March 2015

Abstract
Introduction
Mesenchymal stem cells (MSCs) have potent stabilising effects on vascular endothelium injury, inhibiting endothelial permeability in lung injury via paracrine hepatocyte growth factor (HGF). Recently, it has been indicated that MSCs secrete more factors by MSC-endothelial cell (MSC-EC) interactions. We hypothesised that MSC-EC interactions restore endothelial permeability induced by lipopolysaccharide (LPS) via paracrine HGF.

Methods
We investigated the endothelial permeability induced by LPS under two co-culture conditions. Human pulmonary microvascular endothelial cells (HPMECs) were added into the upper chambers of cell-culture inserts, while two different co-culture conditions were used in the lower side of the transwells, as follows: (1) MSC-EC interaction group: MSCs and HPMECs contact co-culture; (2) MSC group: MSCs only. The endothelial paracellular and transcellular permeabilities in the upper side of transwells were detected. Then the concentration of HGF was measured in the culture medium by using an enzyme-linked immunosorbent assay kit, followed by neutralisation of HGF with anti-HGF antibody in the co-culture medium. In addition, adherens junction and cytoskeleton protein expressions were measured by Western blot and immunofluorescence. HPMEC proliferation was analysed by bromodeoxyuridine incorporation assay.

Results
The paracellular permeability significantly increased after LPS stimulation in a dose-dependent and time-dependent manner. Meanwhile, MSC-EC interaction more significantly decreased endothelial paracellular and transcellular permeability induced by LPS. Moreover, HGF levels in the MSC-EC interaction group were much higher than those of the MSC group. However, neutralising HGF with anti-HGF antibody inhibited the role of MSC-EC interaction in improving endothelial permeability. Compared with the MSC group, MSC-EC interaction increased vascular endothelial (VE)-cadherin and occludin protein expression, reduced caveolin-1 protein expression in HPMECs, and restored remodelling of F-actin and junctional localisation of VE-cadherin. Furthermore, the proliferation ratio in the MSC-EC interaction group was higher than that of the MSC group. However, the effects of MSCs were significantly blocked by anti-HGF antibody.

Conclusions
These data suggested that MSC-EC interaction decreased endothelial permeability induced by LPS, which was attributed mainly to HGF secreted by MSCs. The main mechanisms by which HGF restored the integrity of endothelial monolayers were remodelling of endothelial intercellular junctions, decreasing caveolin-1 protein expression, and inducing proliferation in HPMECs.