bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Influence of Geometry, Wall Thickness, and Material on the Acoustic Resonance Predictions in Closed-Ended Water-Filled Piping
Authors: Mokhtari Alireza , Chatoorgoon Vijay 
Published: April 2014

Acoustic pressure resonances in liquid-transporting pipe systems affect performance and safety. Accurate predictions of acoustic pressure resonances are a necessary requirement for any practical piping system undergoing some acoustic excitations. Thus, understanding the nature of acoustic wave propagation in water filled piping systems needs to be established based on fundamental experiments and analysis. To investigate acoustic resonance, no flow experiments with different configurations, wall thicknesses and materials were compared with theoretical and numerical calculations.
This paper presents an experimental study showing that how linear wave theory, based on a transmission matrix method, and ABAQUS as commercial software do predict the acoustic resonance frequency peaks from 20 to 500 Hz, and discusses the resonant frequency shifts. Study of tube wall thickness, material (stainless steel and Aluminum), some equal and unequal branch configurations and combination of all investigated parameters for “Closed-end” tubes are discussed.
Building a Community - How to Enrich an Engineering Technology Program With an Identity, Presence and Pride
Authors: Miller Amy L. , Samples Jerry 
Published: April 2014

Potential students and their parents are looking at schools differently than in the past: an out cropping of the new generation of parents and students. Academics are still the prime concern but more frequently than in past years families are concerned about the organization. Does the program have an identity that will assist in getting jobs? Is there a presence within the community? Do the faculty and students take pride in what is being accomplished and are graduates proud of their education and their school? The best way to answer these questions is to allow the families a chance to interact with students, see their products, read the posters of their work and show where graduates work.
This paper will discuss the process needed to cultivate an engineering or engineering technology program into one with an identity, presence and ultimately pride. The paper will describe leadership steps that can be taken to generate pride and distinctiveness, first to the faculty, and then to the student body. Resulting in a close nit and enviable community where education can flourish, and the students’ academic related clubs are active and involved on campus. Where alumni look forward to visiting and helping with student projects. Where they take pride in their alma mater and often seek new hires from the program. Where faculty members win teaching awards and enjoy their time in the classroom and advising students.
A case study will be presented and, detailed examples will be cited demonstrating how the students “caught on” and took pride to a new level based on the successful implementation at a university. It will show that leadership lessons learned by students while in school, continued to be used after they graduated. The case study will further demonstrate why everyone associated with the program feels that the engineering technology program is a great place to learn and work.
Structural Health Monitoring of Composite Wind Turbine Blades Using Coherent Guided Waves From Diffuse Fields
Authors: Tippmann J. D. , Lanza di Scalea F. 
Published: April 2014

Diffused acoustic fields exist during the operation in wind turbine blades because of consistent and stochastic loads and the aerodynamic noise generated from turbulent pressure fields. The Green’s function can be extracted from an ensemble average of the cross-correlations of signals recorded from two passive sensors within the diffused acoustic field. Here the wave fields reconstructed are multimodal and dispersive, which makes their extraction challenging. The causal and anti-causal Green’s function is estimated by taking the derivative of the ensemble average of cross correlation.
This method was studied experimentally using a wind turbine test blade (CX-100) located at the UCSD’s Powell Structural Laboratories. A diffuse field was approximated by exciting the skin of the blade with a random signal at several locations using an electrodynamic shaker. The reconstructed Green’s function estimate is compared to experimentally measured impulse response functions. The use of various features of the reconstructed Green’s function for potential applications to structural health monitoring of wind turbine blades is discussed.
Second Law Analysis of Tree-Shaped Fins for the Heat Transfer Enhancement in a PCM Thermal Storage System
Authors: Sciacovelli Adriano , Guelpa Elisa , Verda Vittorio 
Published: April 2014

Latent heat thermal energy storage (LHTES) systems based on phase change materials (PCMs) are a promising option to be employed as effective energy storage devices. PCM allows one to achieve high energy storage density and almost constant temperature energy retrieval, however LHTES systems performance is limited by poor thermal conductivity of the PCMs which leads to unacceptably low melting and solidification rates. Thus, heat transfer enhancement techniques are required in order to obtain acceptable melting and solidification rates.
The preliminary design of a shell-and-tube LHTES unit is investigated by means of computational fluid-dynamics (CFD). Three different fin designs are considered: a conventional radial fin, a constructal Y-shaped fin design and a non-constructal Y-shaped configuration previously investigated by the authors. The performances of each fin configuration are evaluated by means of a Second-law analysis. Moreover, local and global entropy generation rates are analyzed in order to show the main source of thermodynamic irreversibilities occurring in the system.
The analysis indicates that solidification rate is significantly enhanced when Y-shaped fins are adopted in the LHTES unit, however the constructal Y-shaped geometry is not optimal since further improvements can be achieved by means of a Y-shaped fins with elongated secondary branches.
Implications of Thermal Discharge Limits on Future Power Generation in Texas
Authors: Cook Margaret A. , King Carey W. , Webber Michael E. 
Published: April 2014

The recent drought in Texas revealed the vulnerability of curtailment for some power plants due to cooling water supplies being too hot. Assessing the risk of reduced operations at thermoelectric power plants associated with thermal discharge limits, as well the potential for cooperation between power plants, can increase the resiliency of the electricity grid in Texas and aid future planning. This evaluation compares the observed effluent discharge water temperatures from thermoelectric power plants in the Electric Reliability Council of Texas (ERCOT) interconnection with Environmental Protection Agency (EPA) discharge temperature limits. Results indicate that at least two major power plants representing over 3,000 MW of cumulative generation capacity have operated at or near these temperature limits in the past. Predicted warming from heat waves, droughts, or climate change might increase ambient air temperature (one of the primary factors affecting effluent temperature) causing even higher derating in the future.
We modeled current and future average monthly cooling water effluent temperature for open loop and recirculating cooling pond systems in ERCOT using current climate data and predictions of ambient air temperature, electricity generation, dew point, and wind speed for 2027–2032. While there are some power plants that are projected to be exposed to thermal effluent-related curtailment, we estimate that there is six times as much electricity generation potential available from other existing generators that can meet demand without reaching thermal effluent temperature limits. That is, this work’s analysis indicates that other existing power plants could generate additional electricity to offset the curtailment of the particular power plants at greatest risk from derating to maintain grid reliability.
Next Generation Technologies for Improving Product Planning and Development: An Industry Perspective
Authors: Jain Anurag , Thirugnanam Sathish Kumar , Narsingpurkar Atul , Panchal Jitesh H. 
Published: April 2014

Successful product planning and development revolves around great innovation, effective implementation of new ideas, cross-functional collaboration, and right decision making before translating ideas into a right product portfolio, features and technology roadmaps, and finally launching them as successful products. Managing the product planning processes offers multiple challenges in the absence of a healthy idea pipe line, a good visibility into market and competition dynamics, lack of cross functional collaboration and finally, absence of an integrated process and system to support the complex information interplay. Organizations have, in past, adopted different process models and technologies ranging from product data management (PDM), product lifecycle management (PLM), knowledge management and collaboration solutions to address above challenges. However, there is a significant opportunity to leverage next generation technologies such as digital social networking (DSN), cloud computing, and big data management in conjunction with the traditional technologies to improve the efficiency and effectiveness of product planning and development.
This paper presents an industry perspective on the major potential areas where these next generation technologies can be leveraged in the early stages of design, particularly product planning. Specific examples from automotive design and manufacturing are used to illustrate the complementary nature of traditional technologies and the emerging web-based technologies. The paper discusses major industry trends and reviews academic research in this area, and concludes with the authors’ point of view on how the combination of these technologies can be leveraged for developing a profitable product portfolio. The paper also highlights specific research issues from technological and business process standpoint that need to be addressed for successful integration. The potential benefits of such integration include productivity improvements, improved product offerings, first time right & on time product launches.
Towards the Synthesis of Product Knowledge Across the Lifecycle
Authors: Witherell Paul , Kulvatunyou Boonserm , Rachuri Sudarsan 
Published: April 2014

Product lifecycle management is an important aspect of today’s industry, as it serves to facilitate information exchange and management between most, if not all, stages of a product’s existence. As exchanged product information is inevitably subjected to multiple transformations and derivations, information transparency between lifecycle stages can be difficult to achieve. Synthesizing representations of product information across the lifecycle, by creating a lifecycle-stage-independent platform, can provide transparent access to information for both upstream and downstream applications.
In this paper, we review previous and ongoing efforts using ontologies as a means to support information integration and interoperability throughout the lifecycle of a product. We propose that existing efforts can be leveraged to create an upper-tiered ontology for product information. The resulting ontology, a core model for product lifecycle information, would support the synthesis and exchange of product information across lifecycle stages, improving access to this information and facilitating lifecycle thinking.
We discuss the use of ontologies as a means to create and link paradigm-independent representations. We discuss the translations that product information may face when integrated through ontologies, and the extent to which the integrity of the information can be preserved across the lifecycle. We investigate the role of information quality in the exchange and evolution of product information across the lifecycle. Finally, we discuss the application of an upper-tiered ontology, particularly the advantages offered by increased transparency and interoperability, as a means to support lifecycle thinking for mitigating a product’s sustainability impact.
Experimental Investigation and Numerical Optimization of Key Factors Affecting the Programming Efficacy of Passive UHF RFID Tags
Authors: Lum Kassy M. , Proffitt Donnie , Whitney Ann , Parker Johné M. 
Published: April 2014

Radio Frequency Identification (RFID) is a disruptive technology that uses radio waves to uniquely identify objects. As such, it has the potential to bring significant benefits to numerous government and private sector initiatives. However, significant technical challenges remain. A key area of study is in system performance: while the major hardware components in an RFID system (i.e., tags, readers and middleware) have been and continue to be studied extensively, there has been little research, comparatively, in characterizing RFID system performance.
The research presented in this paper was inspired, in part, by a laser printer RFID solution; i.e., one in which the printer simultaneously prints and programs ultra-high frequency (UHF) tags embedded in print media. In this paper, we have conducted a detailed experimental investigation of the primary factors influencing the performance of RFID systems similar to the print solution. This study aims to provide a systematic experimental process for investigating key factors — e.g., the air gap between reader antenna and tag, in-plane orientation of the tag with respect to the reader antenna, and power level output of the reader — which affect the programmability of UHF RFID tags. Results provide a baseline evaluation of the functionality of RFID systems of similar designs and provide a basis for a detailed exploration of the primary factors which affect RFID UHF passive tag dynamic programming capabilities.
By understanding which factors significantly affect the readability and programming of RFID tags, this research suggests optimal designs for system functionality and provides data needed in order to advance such designs. Additionally, a key obstacle for RFID implementation is tag selection. Effectively matching tags to applications requires numerous economic and technical considerations; these considerations generate different implementation constraints. This paper lays the foundation for a multi-objective optimization algorithm to help determine optimal tag selection for a given application, based upon tag performance and cost.
Ice Build-Up Modeling and Performance Analysis of the Customized External-Melt Ice Thermal Energy Storage in the Philippines
Authors: Bongat Ruben A. , Berana Menandro S. 
Published: April 2014

This paper elucidates the mathematical modeling of ice build-up, analysis of performance and projected economic impact of a custom-designed external-melt ice thermal energy storage (TES) that was constructed in the Philippines. Custom-designed TES evaporator coil at compressor-aided, partial storage mode with maximum design ice thickness of 2.95 in (74.93 mm) was used for the TES facility with computed maximum cooling demand of 326.2 TR (1,147 kW).
The model was developed for ice formation rates based on relevant and validated researches. The governing equations for freezing were formed to solve for the weight of water converted to ice and prevailing TES bulk water temperature. All the thermophysical properties of ice expressed as a function of bulk ice temperature with correlated compressor capacity based on actual refrigeration system operating parameters was used.
Performance and cost analyses showed that the custom-designed TES cooling coil requires an increase in initial investment by about 14.26% compared to conventional water chiller of similar capacity by only considering the addition of TES tank, excluding electrical and piping requirements of the chiller and TES systems. Benefits from time-of-use (TOU) rates, wherein electricity is cheaper at night, and coefficient of performance (COP) improvement due to lower ambient temperature at night translate to 31.88% internal rate of return (IRR) at 5-year cash flow or simple payback period of 2.55 years.
Finite Element Formulation for Prediction and Quantification of Stick-Slip Phenomenon in Down-Hole Tubular Expansion
Authors: Al-Abri Omar S. , Pervez Tasneem , Qamar Sayyad Z. , Khan Rashid 
Published: April 2014

The challenges in exploration and development of unconventional oil and gas resources are enormous. The complex reservoir characteristics, and oil and gas flow regimes introduce difficulty in predicting the oil and gas in-place, recovery and production profiles, and wells placement, design and completion. Horizontal drilling and completion using centuries-old manufacturing process of tube forming resulted in producing oil and gas from large areas with smaller footprint on the surface. Though expensive but it optimizes the recovery. The in-situ diametral expansion of tubular using a solid mandrel causes permanent deformation in which the system experiences large frictional forces at mandrel/tubular interface resulting in stick-slip phenomenon. It results in varying tubular thickness and diametral eccentricity which causes structural instability in wells leading to premature failure.
A finite element model describing the dynamics of stick-slip phenomenon in down-hole tubular expansion was developed. Three different set of equations; one each for stick, slip and transition phases were derived using equilibrium equations, time-dependent static friction model and velocity-dependent kinetic friction model. A switch model utilizing the zero velocity interval criterion was used to define stick, slip and transition phases. The newly developed model was implemented in the finite element model by means of two user-defined subroutines namely VFRIC and VDLOAD in commercial finite element software ABAQUS. Experimental and simulation results agree well for expansion force, wall thickness reduction and tubular length shortening. It was found that the thickness variation is the most critical parameter due to its effect in lowering collapse strength of expanded tubular. Parametric study investigations showed that the effect of this phenomenon may possibly be minimized by manipulating mandrel geometry, contact conditions, and/or mandrel speed.
A Method for FE Model Updating of Coupled Vibro-Acoustic Systems Using Constrained Optimization
Authors: Nehete D. V. , Modak S. V. , Gupta K. 
Published: April 2014

Finite element (FE) model updating is now recognized as an effective approach to reduce modeling inaccuracies present in an FE model. FE model updating has been researched and studied well for updating FE models of purely structural dynamic systems. However there exists another class of systems known as vibro-acoustics in which acoustic response is generated in a medium due to the vibration of enclosing structure. Such systems are commonly found in aerospace, automotive and other transportation applications. Vibro-acoustic FE modeling is essential for sound acoustic design of these systems. Vibro-acoustic system, in contrast to purely structural system, has not received sufficient attention from FE model updating perspective and hence forms the topic of present paper.
In the present paper, a method for finite element model updating of coupled structural acoustic model, constituted as a problem of constrained optimization, is proposed. An objective function quantifying error in the coupled natural frequencies and mode shapes is minimized to estimate the chosen uncertain parameters of the system. The effectiveness of the proposed method is validated through a numerical study on a 3D rectangular cavity attached to a flexible panel. The material property and the stiffness of joints between the panel and rectangular cavity are used as updating parameters. Robustness of the proposed method under presence of noise is investigated. It is seen that the method is not only able to obtain a close match between FE model and corresponding ‘measured’ vibro-acoustic characteristics but is also able to estimate the correction factors to the updating parameters with reasonable accuracy.
Molecular Testing for Clinical Diagnosis and Epidemiological Investigations of Intestinal Parasitic Infections
Authors: Verweij Jaco J. , Stensvold C. Rune 
Published: April 2014

SUMMARYOver the past few decades, nucleic acid-based methods have been developed for the diagnosis of intestinal parasitic infections. Advantages of nucleic acid-based methods are numerous; typically, these include increased sensitivity and specificity and simpler standardization of diagnostic procedures. DNA samples can also be stored and used for genetic characterization and molecular typing, providing a valuable tool for surveys and surveillance studies. A variety of technologies have been applied, and some specific and general pitfalls and limitations have been identified. This review provides an overview of the multitude of methods that have been reported for the detection of intestinal parasites and offers some guidance in applying these methods in the clinical laboratory and in epidemiological studies.
Microevolution During Serial Mouse Passage Demonstrates
FRE3
as a Virulence Adaptation Gene in Cryptococcus neoformans
Authors: Hu Guowu , Chen Shu Hui , Qiu Jin , Bennett John E. , Myers Timothy G. , Williamson Peter R. 
Published: April 2014

ABSTRACT

Passage in mice of opportunistic pathogens such as
Cryptococcus neoformans
is known to increase virulence, but little is known about the molecular mechanisms involved in virulence adaptation. Serial mouse passage of nine environmental strains of serotype A
C. neoformans
identified two highly adapted virulent strains that showed a 4-fold reduction in time to death after four passages. Transcriptome sequencing expression studies demonstrated increased expression of a
FRE3
-encoded iron reductase in the two strains but not in a control strain that did not demonstrate increased virulence during mouse passage.
FRE3
was shown to express an iron reductase activity and to play a role in iron-dependent growth of
C. neoformans
. Overexpression of
FRE3
in the two original environmental strains increased growth in the macrophage cell line J774.16 and increased virulence. These data demonstrate a role for
FRE3
in the virulence of
C. neoformans
and demonstrate how the increased expression of such a “virulence acquisition gene” during the environment-to-mammal transition, can optimize the virulence of environmental strains in mammalian hosts.

IMPORTANCE
Cryptococcus neoformans
is a significant global fungal pathogen that also resides in the environment. Recent studies have suggested that the organism may undergo microevolution in the host. However, little is known about the permitted genetic changes facilitating the adaptation of environmental strains to mammalian hosts. The present studies subjected environmental strains isolated from several metropolitan areas of the United States to serial passages in mice. Transcriptome sequencing expression studies identified the increased expression of an iron reductase gene,
FRE3
, in two strains that adapted in mice to become highly virulent, and overexpression of
FRE3
recapitulated the increased virulence after mouse passage. Iron reductase in yeast is important to iron uptake in a large number of microbial pathogens. These studies demonstrate the capacity of
C. neoformans
to show reproducible changes in the expression levels of small numbers of genes termed “virulence adaptation genes” to effectively increase pathogenicity during the environment-to-mammal transition.