bluuebunny/crossref_metadata_2025_split huggingface dataset:
Taxonomic revision of the humpback dolphins (Sousa spp.), and description of a new species from Australia
Authors: Jefferson Thomas A. , Rosenbaum Howard C. 
Published: August 2014

AbstractThe taxonomy of the humpback dolphin genus Sousa has been controversial and unsettled for centuries, but recent work indicates that there are several valid species. A review of multiple lines of evidence from skeletal morphology, external morphology, coloration, molecular genetics, and biogeography, in combination provides strong support for the recognition of four species of Sousa. These include S. teuszii (Kükenthal, 1892), a species with uniform gray coloration and a prominent dorsal hump, which is found in the Atlantic Ocean off West Africa. The species S. plumbea (G. Cuvier, 1829) has similar external appearance to S. teuszii, but has a more pointed dorsal fin. It occurs in the Indian Ocean from South Africa to Myanmar (Burma). The original taxon, S. chinensis (Osbeck, 1765), is reserved for the species that has a larger dorsal fin with no prominent hump, and largely white adult coloration. It ranges from eastern India to central China and throughout Southeast Asia. Finally, we describe a new species of Sousa, the Australian humpback dolphin, which occurs in the waters of the Sahul Shelf from northern Australia to southern New Guinea. It has a lower dorsal fin, more extensive dark color on the body, and a dorsal “cape.” It is separated from the Indo‐Pacific humpback dolphin by a wide distributional gap that coincides with Wallace's Line.
Manipulation of MKS1 gene expression affects Kalanchoë blossfeldiana and Petunia hybrida phenotypes
Authors: Gargul Joanna Maria , Mibus Heiko , Serek Margrethe 
Published: August 2014

SummaryThe establishment of alternative methods to chemical treatments for growth retardation and pathogen protection in ornamental plant production has become a major goal in recent breeding programmes. This study evaluates the effect of manipulating MAP kinase 4 nuclear substrate 1 (MKS1) expression in Kalanchoë blossfeldiana and Petunia hybrida. The Arabidopsis thaliana MKS1 gene was overexpressed in both species via Agrobacterium‐mediated transformation, resulting in dwarfed phenotypes and delayed flowering in both species and increased tolerance to Pseudomonas syringae pv. tomato in transgenic Petunia plants. The lengths of the stems and internodes were decreased, while the number of nodes in the transgenic plants was similar to that of the control plants in both species. The transgenic Kalanchoë flowers had an increased anthocyanin concentration, and the length of the inflorescence stem was decreased. The morphology of transgenic Petunia flowers was not altered. The results of the Pseudomonas syringae tolerance test showed that Petunia plants with one copy of the transgene reacted similarly to the nontransgenic control plants; however, plants with four copies of the transgene exhibited considerably higher tolerance to bacterial attack. Transgene integration and expression was determined by Southern blot hybridization and RT‐PCR analyses. MKS1 in wild‐type Petunia plants was down‐regulated through a virus‐induced gene silencing (VIGS) method using tobacco rattle virus vectors. There were no significant phenotypic differences between the plants with silenced MKS1 genes and the controls. The relative concentration of the MKS1 transcript in VIGS‐treated plants was estimated by quantitative RT‐PCR.
Swing Voting due to Smartvote Use? Evidence from the 2011 Swiss Federal Elections
Authors: Pianzola Joëlle 
Published: August 2014

AbstractAlmost every fifth voter in Switzerland visited the Voting Advice Application (VAA) smartvote prior to casting a ballot in the 2011 Swiss federal elections. Surveys among users reveal that the web application led voters to discover suitable candidates or parties which they previously would not have considered. The subsequent question therefore is whether the VAA initiates a change in party choice among voters. In this paper, we examine whether voters who used smartvote were more likely to swing vote in the 2011 elections than non‐users. Moreover, we take a look at which parties might have benefited from a voter flow among smartvote users. We employ both selection models and propensity score matching for tracing the causal effect of smartvote use on party choice. According to our results, smartvote users were significantly more likely to swing vote in the elections. Voter migration among smartvote users was most prominent towards the Green Liberal Party, one of the two major winners of the 2011 Swiss federal elections.
The Least Penalty Optimization Prioritization Operators for the Analytic Hierarchy Process: A Revised Case of Medical Decision Problem of Organ Transplantation
Authors: Yuen Kevin Kam Fung 
Published: August 2014

ABSTRACTThe Analytic Hierarchy Process (AHP) is one of the popular methods to support human decision making. Prioritization method leading to the possibility of rank reversal is still one of the unsettled issues of the AHP, although many applications of this method have been made. In this study, 10 important prioritization methods are reviewed and compared. To evaluate the fitness of the prioritization operators (POs), on the basis of existing PO measurement criteria, this research proposes the Root Mean Penalty Weighted Square Variance (RMPWSV) as a reasonable measurement criterion. Graphical solution demonstrates the computational concept for the RMPWSV. On the basis of the RMPWSV, two Least Penalty Optimization (LPO) POs are proposed as the new perspectives for solving the prioritization problems: Least Product of Penalty and Direct Squares (LPPDS) and Least Product of Penalty and Weighted Squares (LPPWS). The comprehensive numerical analyses verify that LPPDS is the fittest PO with respect to the RMPWSV. To demonstrate improvement of the proposed method, a medical decision problem for organ transplantation is revised by using 11 developed POs and two proposed POs with respect to RMPWSV measurement. LPPDS is the ideal PO, instead of Eigenvector method, to generate a priority vector for a decision problem in various fields, such as social science, politics, business, finance, medical treatment, resource management, and engineering management.
A Framework for Space Systems Architecture under Stakeholder Objectives Ambiguity
Authors: Golkar Alessandro , Crawley Edward F. 
Published: August 2014

ABSTRACTMatching high ambitions with scarce resources is one of the primary challenges of aerospace and other industries concerned with the development of unprecedented infrastructures, on par with the technical challenges associated with developing new technology. Stakeholder objectives are often unclear due to highly exploratory business cases. Further ambiguity emerges from disagreement between stakeholders and decision makers called to formulate scientific, technological and policy requirements for new systems.This paper develops a structured approach, called the Delphi‐based Systems Architecting Framework (DB‐SAF), which has been conceived to develop recommendations to system architects concerned with the design of unprecedented large infrastructures for which objectives are ambiguous or unclear.The objectives of DB‐SAF are to identify sources of ambiguity in the value proposition of a system architecture and the associated trade‐space exploration, characterize and model sources of ambiguity, and assess the impact of requirement ambiguities on the architectural trade space.The proposed systems architecting approach is demonstrated in this paper through the assessment of a robotic Mars Sample Return Campaign, which serves as a test bed case study to describe the proposed methodology and to discuss its extension to other fields of engineering.The proposed framework integrates methods from systems engineering, computational systems architecting, multidisciplinary systems design and optimization, uncertainty modeling, utility theory, and social science research. It allows decision makers to visualize an architectural synthesis of aerospace systems, understanding adverse impacts of ambiguity, and supporting negotiations among stakeholders for efficient compromise in systems architecting.
Propulsion System Integration of Turboprop Aircraft for Basic Trainer
Authors: Kong Changduk 
Published: August 2014

The propulsion system integration of a turboprop aircraft, which has been developed for the basic trainer, was performed. The proper turboprop engine was selected among worldwide existing engines by the specific developed engine selection technique and trade-off studies such as customer’s request for operational capability (ROC), propulsion system parameters, performance analysis with engine installed effects, future growth potential, integrated logistic support (ILS), maintainability, interfaces with the airframe, etc. The chin type air inlet with the plenum chamber was designed in consideration of the inclined configuration to minimize the propeller swirl effect, the inertial separation bypass device to reduce FOD, and the super-ellipse and NACA-1 profile lip to maximize the ram recovery. The air inlet was analyzed by a higher-order source panel method considering propeller wake.
The exhaust duct was designed through internal cross-section area determination to maximize the cruising power as well as external configuration to maximize the effective power, to minimize the aerodynamic drag and to minimize the cockpit contamination by the exhaust gas. The proper oil cooler for the selected turboprop engine was determined with cooling requirements and the oil cooling inlet duct with NACA configuration was designed.
The test of the propulsion system including the installation performance test with the effects of the air inlet, the exhaust duct, the propeller and the nose fuselage configuration was performed in the test cell.
Advanced Diagnostic and Prognostic Technologies for Gas Turbine Engine Risk Assessment
Authors: Roemer Michael J. , Kacprzynski Gregory J. 
Published: August 2014

Real-time, integrated health monitoring of gas turbine engines that can detect, classify, and predict developing engine faults is critical to reducing operating and maintenance costs while optimizing the life of critical engine components. Statistical-based anomaly detection algorithms, fault pattern recognition techniques and advanced probabilistic models for diagnosing structural, performance and vibration related faults and degradation can now be developed for real-time monitoring environments. Integration and implementation of these advanced technologies presents a great opportunity to significantly enhance current engine health monitoring capabilities and risk management practices.
This paper describes some novel diagnostic and prognostic technologies for dedicated, real-time sensor analysis, performance anomaly detection and diagnosis, vibration fault detection, and component prognostics. The technologies have been developed for gas turbine engine health monitoring and prediction applications which includes an array of intelligent algorithms for assessing the total ‘health’ of an engine, both mechanically and thermodynamically. This includes the ability to account for uncertainties from engine transient conditions, random measurement fluctuations and modeling errors associated with model-based diagnostic and prognostic procedures. The implementation of probabilistic methods in the diagnostic and prognostic methodology is critical to accommodating for these types of uncertainties.
Identifying Faults in the Variable Geometry System of a Gas Turbine Compressor
Authors: Tsalavoutas A. , Mathioudakis K. , Stamatis A. , Smith M. 
Published: August 2014

The influence of faults in the variable geometry (variable stator vanes) system of a multistage axial compressor, on the performance of an industrial gas turbine is investigated. An experimental investigation has been conducted, by implanting such faults into an operating gas turbine. The faults examined are individual stator vane mistuning of different magnitude, and located at different stages.
Fault identification is based on the aerothermodynamic measurement data and is achieved by employing two different techniques, namely adaptive performance modelling and monitoring the circumferential distribution of the turbine exit temperature. It is observed that the deviations of the health indices produced by an adaptive performance model, form patterns that can be used to identify the faults. The patterns characterize both the kind and the magnitude of the fault. On the other hand, the turbine exit temperature profile is also influenced and its change can be used as additional information, to increase the confidence level of the diagnosis (contrary to customary practice, which expects temperatures profiles to reflect only burner or turbine malfunctions).
An Object-Oriented Program for the Dynamic Simulation of Gas Turbines
Authors: Agresti M. , Camporeale S. M. , Fortunato B. 
Published: August 2014

An object-oriented program for the dynamic simulation of gas turbines has been developed using Matlab-Simulink® utilities. The advantages given by the object-oriented program are the flexibility and the user-friendly interface. The components of the gas turbine are modeled as blocks that can be assembled like an engineering drawing in which the connections between two elements represent either a mechanical power transfer or a fluid transfer. In a fluid-type connection the data regarding the fluid composition, the thermodynamic properties and the fluid velocity are simultaneously transferred. A library of gas turbine components has been developed: each component appears as a block that can be placed into the drawing by means of click-and-drag operations.
In order to obtain an accurate description of the physical processes characterizing the gas turbine, the components are described by a set of non-linear algebraic equations and ordinary differential equations. Each component block is created using the graphical programming tools of Simulink, following a block diagram approach. Specific blocks have been created for the evaluation of the thermodinamic properties of the working fluids. The paper provides the description of the mathematical model adopted for the simulation and the some examples of the Matlab-Simulink formulation adopted for implementing the model. The accuracy of the program has been verified considering test cases for which experimental data are available in the public literature.
The computational times, tested for the transients of a single-shaft and a double-shaft gas turbine, resulted to be very short, even making use of a personal computer.
Fuzzy Fuel Flow Selection Logic for a Real Time Embedded Full Authority Digital Engine Control
Authors: Martucci Angelo , Volponi Allan J. 
Published: August 2014

The control logic of the modern Full Authority Digital Engine Control (FADEC) is comprised of many control loops, each of which has a specific purpose. Typical control loops include (but are not limited to) a high or low rotor speed governor, an Acceleration and Deceleration loop, and various limiting loops for temperature, speed, fuel flow, and rate of change of fuel flow. The logic that determines which of these loops is “in control” at any particular time has a history of being very simplistic. This Selection Logic is usually nothing more that a cascade of minimum and maximum selection logic gates. Since this logic is so simplistic, the control engineer often has to “fine tune” the compensator design for each loop, in order to achieve proper performance.
The purpose of this paper is to a present a means of achieving a selection logic design based on Fuzzy Logic principles. Hereafter, this shall be referred to as a Fuzzy Fuel Flow Selector. The paper provides a brief overview of the most typical architecture for real time embedded FADEC control logic, rule development for the Fuzzy Fuel Flow Selector, and a realistic implementation of the Fuzzy Fuel Flow Selector. Also provided is a typical application that is used to contrast the performance between traditional selection logic and the Fuzzy Fuel Flow Selector. An overview of the Fuzzy Logic process is also included for completeness.
Understanding Machinery Management — Using Machine Condition and Process Information for Maximum Benefit
Authors: Harker Roger G. 
Published: August 2014

The use of machinery protection systems is well-established in industry. These systems shut down a machine or return it to a safe or nondestructive mode of operation without human intervention. Protection systems are used to ensure personnel safety, prevent or minimize machine damage, and limit environmental impact. While these are substantial benefits, machinery protection remains inherently reactive, and the approach is still necessary, but no longer sufficient in today’s economic environment. Machinery management is increasingly recognized for its ability to indicate machinery condition before a protection system’s alarm levels are exceeded. By providing an early warning of what is happening with the machine, proactive decisions can be made about how machinery assets are run and how they affect the plant. Machinery management requires the correlation of critical process data with vibration and position data. It allows event correlation and effective root cause analysis. Information resulting from effective machinery management is actionable because it results from continuous online audits of machinery, and indicates when action is required and how best to take it. Machinery management helps answer key questions, such as: How long can this machine run? Can the process be adjusted to extend the operation and avoid a shutdown? If you want to proactively manage machinery and optimize machinery performance along with the process, you must have an effective machinery management program.
This paper explores the practice of machinery management, including what it is, what is considered “best practice,” and what the resulting benefits are.
Suppression of Dynamic Combustion Instabilities by Passive and Active Means
Authors: Berenbrink Peter , Hoffmann Stefan 
Published: August 2014

In the gas turbine industry, lean premixed combustion is a state-of-the-art technology for the reduction of NOx emissions. Due to the ever increasing reaction densities and turbine inlet temperatures in modern gas turbines, the combustors reveal an increased tendency to form dynamic combustion instabilities.
This paper reports on the use of passive and active methods for the suppression of combustion oscillations in heavy-duty gas turbines featuring lean premixed combustion:
Modifications of the burner exit nozzle are implemented in order to avoid fluiddynamic feedback and to change the acoustic behavior of the flame.
An asymmetric circumferential distribution of flames with different thermoacoustic responses serves to avoid or at least attenuate the self-excitation within the combustor in multiburner systems.
In some applications, these methods are successfully coupled with an active system for the suppression of combustion instabilities (AIC) to further extend the operation envelope.
Field demonstrations in different Siemens gas turbines serve to demonstrate the benefit and flexibility of these measures for practical gas turbine combustion systems.
Influence of the Combustor Aerodynamics on Combustion Instabilities From Equivalence Ratio Fluctuations
Authors: Sattelmayer Thomas 
Published: August 2014

Gas turbine combustors are often susceptible to self excited oscillations, which lead to unacceptable levels of pressure, velocity and heat release fluctuations. Although instabilities can occur in systems with locally constant equivalence ratio, it is very important to take into account the influence of equivalence ratio fluctuations, which are generated in the fuel air mixer in the unstable case. These fluctuations are convected into the flame and lead to an additional mechanism for the generation of heat release fluctuations. Moreover, entropy waves are produced in the flame, which travel through the combustor and generate additional pressure waves during the acceleration of the flow at the combustor exit.
To date, available theories use the physically unrealistic assumption that the equivalence ratio waves as well as the entropy waves are convected downstream without any spatial dispersion due to the combustor aerodynamics. An analytical approach is presented, which allows to take the spatial dispersion into consideration. For that purpose, the response of the burner and the combustor to an equivalence ratio impulse or an entropy impulse is calculated using the Laplace transformation and a more general transfer function for harmonic waves is derived. The obtained expression has three parameters, which represent the influence of the burner or the combustor aerodynamics, respectively. This equation can be used in numerical codes, which represent the combustion system through a network of acoustic multiports, if the equivalence ratio and the entropy are added to the vector of variables considered. The parameters required for the dynamic combustor model can be deduced from a detailed CFD analysis of the combustor flow in case of the application of the theory to a particular combustor design.
As an example, a simple model combustor is used to demonstrate the application of the theory. It is highlighted how the spatial dispersion of the equivalence ratio and entropy fluctuations can be included in the stability analysis. The calculated examples reveal that the influence of both variables on the generation of instabilities is highly overpredicted if the spatial dispersion is not taken into account. Furthermore, it can be deduced from the study, that burner and combustor designs with a wide range of convective time scales have advantages with respect to the stability of the combustor.