bluuebunny/crossref_metadata_2025 huggingface dataset:
A TALE OF TWO CLIMATES: DIVERSITY CLIMATE FROM SUBORDINATES’ AND MANAGERS’ PERSPECTIVES AND THEIR ROLE IN STORE UNIT SALES PERFORMANCE
Authors: McKAY PATRICK F. , AVERY DEREK R. , MORRIS MARK A.
Published: November 2009

Applying Zohar's (2000) multilevel model of organizational climate, this study assessed the main and interactive effects of subordinates’ and managers’ diversity climate perspectives on store sales performance. Across 654 store units of a large U.S. retail organization, we observed main effects of subordinate and managerial diversity climates on unit sales percentage change and a significant subordinate × manager diversity climate perspective interaction. The greatest sales growth was found in stores wherein subordinates and management perceived highly pro‐diversity climates (positive consistency). In contrast, the lowest sales growth was evident for stores in which both subordinates and managers reported less hospitable diversity climates (negative consistency). Our findings underscore the positive financial ramifications of highly consistent perceptions that diversity is valued in a work context.
PROGRESSION THROUGH THE RANKS: ASSESSING EMPLOYEE REACTIONS TO HIGH‐STAKES EMPLOYMENT TESTING
Authors: McCARTHY JULIE , HRABLUIK COREEN , JELLEY R. BLAKE
Published: November 2009

Employee reactions to promotional examinations were investigated in 2 studies (N = 498 & 182, respectively) of police officers. Anxiety, motivation, and justice perceptions were examined as possible predictors of promotional exam performance and intentions to recommend the exam to others. Reactions to a promotional examination were significantly and differentially related to those criteria. Motivation predicted performance whereas justice perceptions predicted recommendation intentions. In Study 2, the role of cognitive processing was also investigated. Results indicated that candidate reactions predicted exam performance through cognitive processing mechanisms. Exam motivation facilitated cognitive processing, which resulted in higher levels of exam performance. In contrast, exam anxiety exhibited both facilitative and debilitative cognitive processing effects.
Synthesis: Land Transitions in the Tropics
Authors: Uriarte María , Schneider Laura , Rudel Thomas K.
Published: November 2009

Land cover transformations in the tropics are not limited to deforestation; they include other complex transitions such as agricultural and urban expansion, pasture development, and secondary vegetation regrowth. Understanding the causes and extent of these highly variable and complex transitions requires close collaboration between biological, physical, and social scientists. Here we address three critical issues in the study of land transitions: (1) What methodological and socioecological criteria should be used for characterizing land cover categories and transformations? Results from case studies presented here call for the creation of continuous land cover classes that allow for detection of disturbance and human use dynamics and consideration of socioeconomic and biophysical criteria in characterizing and monitoring land transitions. (2) What are the most promising theoretical frameworks? Successful theoretical frameworks must bridge disciplinary boundaries, and encompass multiple spatial, temporal, and political scales. (3) Are regime shifts, constraints, and resilience of land transformations in the tropics predictable? Resilience of land use systems requires a feedback loop between ecological constraints and management decisions. This loop may be broken by policies, migration, and flow of capital from global commodity markets. In addition, land transformations may lead to novel interactions between land‐use and natural disturbance leading to unpredictable regime shifts in ecosystems. Planning for sustainable patterns of land use requires some understanding of these regime transformations.
Passerine Pollination of Rhodoleia championii (Hamamelidaceae) in Subtropical China
Authors: Gu Lei , Luo Zhonglai , Zhang Dianxiang , Renner Susanne S.
Published: November 2009

The pollination ecology and breeding system of the Hamamelidaceae tree species Rhodoleia championii were studied in an evergreen broad‐leaved forest in Nankunshan National Forest in Guangdong Province in China. Rhodoleia championii produces lipid‐rich pollen grains and dilute nectar (averaging 0.7 mL/d and 9% sugar), with nectar production peaking before 0800 h; the species is self‐incompatible and does not set seed asexually. Seven species of nectar‐foraging birds visited the inflorescences, with the most common visitors being Japanese white‐eyes (Zosterops japonicus, Zosteropidae) and fork‐tailed sunbirds (Aethopyga christinae, Nectariniidae). Bumblebees and honeybees played limited roles as pollinators. As documented by fossils from Europe, the Rhodoleia stem lineage dates back at least to the Paleocene. Bird pollination, however, is unlikely to have evolved before the Oligocene when sunbirds arrived in Europe, and pollination by Z. japonicus cannot be much older than 250,000 million years ago, when Z. japonicus diverged from its closest relative.
Strategic Pricing Behavior under Asset Value Maximization
Authors: Wang Shinn‐Shyr , Stiegert Kyle W. , Dhar Tirtha P.
Published: November 2009

In this paper, we empirically evaluate strategic pricing behavior and shareholder delegation of financial market objectives in the U.S. butter and margarine market. Shareholders are assumed to maximize the value of firm assets according to a certainty equivalent capital asset pricing model (CAPM). The delegation setup instructs managers to maximize a linear combination of firm profits and shareholder equity values. A key result from the analysis is that a test of financial market influences cannot be rejected in the product market for butter and margarine. Product market competition is best described using a conjectural variation model of industrial organization. Estimates of Lerner Indexes suggest significant market power and counterfactual simulations point toward significant biases in estimated Lerner Indexes when capital market dimensions are ignored or if the wrong market structure is assumed.

Dans le présent article, nous avons effectué l'évaluation empirique de comportements stratégiques dans la détermination des prix et la délégation d'objectifs financiers de la part d'actionnaires sur le marchéétatsunien du beurre et de la margarine. Nous avons supposé que les actionnaires maximisent la valeur de l'actif d'une firme selon l'équivalent certain du modèle d'évaluation des actifs financiers (MEDAF). La structure de la délégation amène les gestionnaires à maximiser une combinaison linéaire des profits de la firme et de la valeur nette des actions. L'un des principaux résultats de l'analyse est qu'un test des influences du marché des capitaux sur le marché des produits ne peut être rejeté pour le cas du beurre et de la margarine. La concurrence sur le marché des produits est plus adéquatement caractérisée par un modèle d'organisation industrielle à variations conjecturales. Les estimations de l'indice de Lerner ont indiqué la présence de pouvoir de marché, et les simulations contrefactuelles ont montré des biais significatifs dans les valeurs estimées des indices de Lerner lorsque l'on ne tient pas compte du marché des capitaux ou que l'on suppose une structure de marché erronée.
The utility of the Sysmex XE‐2100 analyzer’s NEUT‐X and NEUT‐Y parameters for detecting neutrophil dysplasia in myelodysplastic syndromes
Authors: FURUNDARENA J. R. , ARAIZ M. , URANGA M. , SAINZ M. R. , AGIRRE A. , TRASSORRAS M. , URESANDI N. , MONTES M. C. , ARGOITIA N.
Published: November 2009

The diagnosis of myelodysplastic syndromes (MDS) is based on morphological changes in the blood and bone marrow. The parameters NEUT‐X and NEUT‐Y of the Sysmex XE‐2100 analyzer could help detect neutrophil dysplasia. A control group of 50 patients, along with 50 postpartum patients, 50 anemias, 50 leukopenias, 50 patients with microscopically visible hypergranulated neutrophils and 50 MDS patients were assessed. The NEUT‐X and NEUT‐Y values (mean ± SD) for the control group were 1346 ± 28.2 and 420 ± 19.3, respectively, with the anemia and leukopenia groups giving similar values. The postpartum and hypergranulated neutrophils groups presented higher values (P < 0.05), whereas the values in the MDS group were 1286 ± 72.8 and 385 ± 50.9 (P < 0.05), respectively. There were no differences between the morphological MDS types. The NEUT‐X and NEUT‐Y values in MDS patients with optical hypogranulation were significantly lower than for MDS patients without optical hypogranulation. NEUT‐X and NEUT‐Y values lower than 1298 and 398, respectively, would have a specificity for detecting MDS of 94% and 91% and would detect 60% and 56% of cases, respectively, whereas they would detect 75% and 74%, respectively, of MDS cases with optical hypogranulation. NEUT‐X and NEUT‐Y parameters can be used to detect neutrophil dysplasia arising from MDS and chronic myelomonocytic leukemia.
The Hôtel de Bourgogne in 1760: Some Previously Unpublished Drawings by Louis‐Alexandre Girault
Authors: GOLDER JOHN
Published: November 2009

For Donald Roy

and in memory of David Illingworth and Graham Barlow

Built in 1548, the Hôtel de Bourgogne was in almost continuous use as a theatre for 235 years. We have, until now, had only an approximate idea of the internal layout of the auditorium and virtually no idea at all of the way in which the outbuildings were arranged. Recently, however, a series of architectural plans has come to light in the French National Archives. They date from 1760, which was when Papillon de La Ferté, who was in overall charge of the Royal Entertainments Department (les Menus‐Plaisirs), ordered that the auditorium be both extensively refurbished and made more attractive, in order to increase audiences and to rescue the Italian players from a financially parlous position. Louis‐Alexandre Girault, an architect attached to the Royal Entertainments, was put in charge of the work. The five plans and the longitudinal section which he has left us – and which are published and discussed here for the first time – allow us not only to visit the various different parts of the auditorium and stage, but also to have access to the public spaces, the actors' dressing rooms and their administrative offices, and even to go down into the store‐rooms below the auditorium and the stage.
Repertory Reforms at the Paris Opéra on the Eve of the Revolution*
Authors: DARLOW MARK
Published: November 2009

This article examines the principal reforms made to the repertoire of the Paris Opéra in the 1780s. The main aim was to encourage the submission of new works to the Opéra, hence to grow its repertoire, by means, first, of a competition for librettos under royal sponsorship and, second, of a reform of the system of authors' rights. The correspondence which passed between Dauvergne, the director of the Opéra, and Papillon de La Ferté, who was in charge of the Royal Entertainments Department (les Menus‐Plaisirs), also reveals an attempt to correct what it calls the insubordination of the principal subjects. Among other points, there was the question of changing the salary system in order to make salaries depend on the number of performances, thus ensuring a higher quality of performance. But, as the Chéron case proves (they were dismissed in 1790 for going absent without leave), artists were increasingly concerned for their public reputation and considered themselves less and less to be ‘subjects’ of the king's household. The third type of reform concerned the use of try‐out rehearsals in order to sift the libretti and eliminate those unlikely to prove successful in performance, before beginning the production process. Thus we see how the directors and the officers of the king's household were in fact attentive to correcting certain abuses in the management of the institution well before 1789, contrary to the commonly held view that the privileged theatres had ossified in the decades before the Revolution.
Une scénographie de Servandoni conservée pour les spectacles de l'Opéra à Paris: le décor de la ville de Thèbes du Triomphe de l'harmonie (1737)
Authors: DE LA GORCE JÉRÔME
Published: November 2009

Until now, the work of Jean‐Nicolas Servandoni for the lyric stages of Paris has only been known through archival papers, descriptions published in the Mercure de France and a handful of stage plans and sections. However, a drawing held in the Musée des arts décoratifs in Lyon allows us to see for the first time what one of his set designs for the stage of the Opéra may actually have looked like. Thanks to manuscript notes penned on the drawing in the eighteenth century, it is possible to accurately identify and attribute the drawing, of which no detailed examination has previously been undertaken. Although it does not show the stage picture in its entirety, the design – conceived in 1737 for the third entrée of Grenet and Lefranc de Pompignan's opéra‐ballet, Le triomphe de l'harmonie– carries an overlay, showing how a key moment in the drama was staged. It illustrates the moment at which Amphion, to protect the city of Thebes from attack by savages, magically causes new walls to rise into place ‘par le charme de sa voix’. Unpublished sources offer evidence of this scene's success, which was due in no small part to Servandoni, and to his involvement in the production just before he left the Opéra to create some even more spectacular settings at the Salle des Machines in the Tuileries Palace.
Gaps, Pauses and Expressive Arms: Reconstructing the Link between Stage Gesture and Musical Timing at the Académie royale de musique
Authors: WENTZ JED
Published: November 2009

One of the most salient features of French Baroque opera was its moulding of music, text and acting into a unified whole. This rigorous aesthetic resulted in a distinct performance style, one which melded the music and the singers' gestures on stage. This article will examine the possibility of a symbiotic relationship between stage action and passionate musical expression in France. Using the writings of Rousseau, Rameau and other participants of the Querelle des Bouffons as a starting point, the central place of the theory of the passions in the acting and musical aesthetics of the day will be examined. Special attention will be given to Lallemant's Essai sur le méchanisme des passions (1751), in which the physical manifestation of the passions in the human body is clearly linked to musical tempo. Having established the medical basis for such a link, it is easy to see how, aesthetically, a change of tempo would be felt as a change of affect and thus result in a physical change in the actor's gesturing body.
VASCULAR DIALYSIS ACCESS FLOW MEASUREMENT: EARLY INTERVENTION THROUGH EARLY DETECTION
Authors: Miguel Susana San , Chow Josephine
Published: November 2009

Aim: The aim of the project is to determine the effectiveness of using online access flow measurement, thermodilution method (Fresenius BTM™), in detecting and predicting thrombosis or stenosis of the haemodialysis fistula, so that early intervention could be instituted. Methodology: All haemodialysis patients with permanent vascular dialysis access, either arteriovenous fistula (AVF) or arteriovenous fistula graft (AVG), in a large tertiary referral Dialysis Service in Australia were included in this prospective observational quality project, conducted over 12 months.

Results: Out of 165 patients studied, 36 patients were found to have poor dialysis access flow, defined as AVF—flow of <200 ml/min or a decrease of 25% from last measurement or AVG—flow of <600 ml/min or a decrease of 25% from last measurement. Doppler ultrasounds were performed, and confirmed findings of significant stenosis, either on the arterial or venous sites, as indicated by poor dialysis access flow results.

Conclusion: Thermodilution technique is a reliable and effective method of detecting poor dialysis access flow for patients with permanent vascular access, comparable with other techniques.
IMPLEMENTING THE BUTTONHOLE METHOD USING THE BIOHOLE PEG IN A BUSY DIALYSIS UNIT: A REPORT OF THE DEVELOPMENT OF CURRENT PRACTICE
Authors: King Jennie
Published: November 2009

A report outlining experience gained from the practice of introducing the buttonhole (BH) method of arteriovenous cannulation using the Biohole device, a polycarbonate sterile peg, to form the tunnel tracks. The author's findings are discussed informally and compared with current published literature to provide encouragement to nursing colleagues who are interested in introducing this method of needling, using the peg, into a typically busy haemodialysis unit.
Advocacy in the Age of Authoritarianism: Adjustments of all Sorts in Egypt
Authors: Tadros Mariz
Published: November 2009

This paper examines how advocacy, a highly political concept became a depoliticised technocratic buzzword for many donors, international and local NGOs. The focus of the paper is on the top‐down introduction of advocacy in the Egyptian context in the 1990s as part of the bid to promote democratisation in the Arab world. It argues that in authoritarian contexts, participatory advocacy is inimical to the inhibitive policy environment and the nature of the political culture in place.

The paper relies on a series of case studies involving donor‐state‐civil society interfaces in supporting advocacy. It draws in particular on the largest funding scheme to promote advocacy in the country, a USAID initiative involving a consortium of partners. It tracks the transformations that took place in order to convert advocacy into a ‘government‐friendly’ form of engagement and reflects on the inherent tensions for donors backing a politicised form of development that clashes with their foreign policy.

The paper argues that often advocacy NGOs are disembedded from the wider context due to a focus on the policy influence arena where they are expected to elicit change. Insufficient incentives to mobilise a constituency as well as a politically restrictive environment means that sometimes advocacy oriented initiatives or organisations ignore prompts from citizen groups engaged in contentious politics. Many advocacy NGOs engage in an elite way that impacts negatively on policies and on downward accountability towards a weak or nonexistent constituency. This not only has implications for their positionality in their contexts but also on the nature of policy demands made as well.
Excitability parameters and sensitivity to anemone toxin ATX‐II in rat small diameter primary sensory neurones discriminated by Griffonia simplicifolia isolectin IB4
Authors: Snape Alistair , Pittaway James F. , Baker Mark D.
Published: November 2009

Sensory neurone subtypes (≤ 25 μm apparent diameter) express a variety of Na+ channels, where expression is linked to action potential duration, and associated with differential IB4‐lectin binding. We hypothesized that sensitivity to ATX‐II might also discriminate neurones and report that 1 μm has negligible or small effects on action potentials in IB4 +ve, but dramatically increased action potential duration in IB4 −ve, neurones. The toxin did not act on tetrodotoxin‐resistant (TTX‐r) NaV1.8 currents; discrimination was based on tetrodotoxin‐sensitive (TTX‐s) Na+ channel expression. We also explored the effects of varying the holding potential on current threshold, and the effect of repetitive activation on action currents in IB4 +ve and −ve neurones. IB4 +ve neurones became more excitable with depolarization over the range −100 to −20 mV, but IB4 −ve neurones exhibited peak excitability near −55 mV, and were inexcitable at −20 mV. Eliciting action potentials at 2 Hz, we found that peak inward action current in IB4 +ve neurones was reduced, whereas changes in the current amplitude were negligible in most IB4 −ve neurones. Our findings are consistent with relatively toxin‐insensitive channels including NaV1.7 being expressed in IB4 +ve neurones, whereas toxin sensitivity indicates that IB4 −ve neurones may express NaV1.1 or NaV1.2, or both. The retention of excitability at low membrane potentials, and the responses to repetitive stimulation are explained by the known preferential expression of NaV1.8 in IB4 +ve neurones, and the reduction in action current in IB4 +ve neurones with repetitive stimulation supports a novel hypothesis explaining the slowing of conduction velocity in C‐fibres by the build‐up of Na+ channel inactivation.
Frequency Tuning of a Disk Resonator Gyro Via Mass Matrix Perturbation
Authors: Schwartz David , Kim Dong Joon , M’Closkey Robert T.
Published: November 2009

Electrostatic tuning of the resonant modes in microelectromechanical vibratory gyroscopes is often suggested as a means for compensating manufacturing aberrations that produce detuned resonances. In high performance sensors, however, this approach places very stringent requirements on the stability of the bias voltages used for tuning. Furthermore, the bias voltage stability must be maintained over the operating environment, especially with regard to temperature variations. An alternative solution to this problem is to use mass perturbations of the sensor’s resonant structure for resonant mode tuning. This paper presents a new mass perturbation technique that only relies on the sensor’s integrated actuators and pick-offs to guide the mass perturbation process. The algorithm is amenable to automation and eliminates the requirement that the modal nodes of the resonator be identified by direct measurement.
Analysis of Brazing Stresses in Ceramic-Metal Joints in High-Vacuum Devices
Authors: De Weese K. L. , Toups C. E. , Dharan C. K. H.
Published: November 2009

Significant stresses are induced in brazed metal-to-ceramic joints during cool-down. Analysis of such stresses is complicated by nonlinear material behavior and uncertainties in material properties at and near the braze temperatures. In this study, stresses induced during cool-down from the brazing temperature are analytically determined for a coaxial RF (radio frequency) window, which is an integral component of many traveling-wave tube (TWT) devices. The approach is to use nonlinear finite element analysis which takes into account plastic deformation of the metal components as well as the temperature dependence of material properties. Details of the modeling techniques, analytical assumptions and boundary conditions employed are discussed. In addition, metallographic analysis of the brazed test assemblies is described. Analytically predicted stress distributions showed reasonably good correlation with both the location and direction of cracks observed in the ceramic component of brazed sample test assemblies. The results of this investigation emphasize the need for accurate material properties for the braze alloys used in such joints, including temperature dependence, as well as an understanding of their nonlinear behavior, for the stress analysis model to be accurate. In addition, the important role of joint geometry in the minimization of cool-down stresses in brazed metal-ceramic assemblies is described.
Stress and Tolerance Analysis for Zero Insertion Force (ZIF) Connector
Authors: Engel P. A. , Nemier S. E. , Toda M. D.
Published: November 2009

A zero-insertion-force (ZIF) connector spring was designed with the multiple requirements of maintaining precise normal force, yielding sufficient wipe, and having low friction-and-wear characteristics. Since accurate response data as well as quick appraising methods were needed, both analytical and numerical (finite element) methods of stress analysis were used to calculate actuation against a circuit card contact. Both material plasticity and large deformation nonlinearities were considered to ensure design integrity. A statistical tolerance study of the ZIF connector was performed using Monte Carlo techniques. The results were used to provide dimensional limits for strength, and to predict the probability of contacts projecting into the circuit card slot, impeding connector actuation.
Automated Electronic Circuit Manufacturing Using Ink-Jet Technology
Authors: Wallace D. B.
Published: November 2009

The feasibility of using ink-jet technology to write circuits on PC board material and TAB substrate has been demonstrated. Several systems were evaluated and the most successful system used paraffin as a resist material on a copper substrate. The copper was etched and the paraffin subsequently removed to form the conductive paths of the circuit. Line widths down to 100μm were achieved, and line widths of 50μm were shown feasible. The generation of the print pattern from a computer file illustrated the potential of coupling a circuit writing system to an electrical CAD system to provide rapid turnaround prototype circuits.
An Overview of Integrated Circuit Device Encapsulants
Authors: Wong C. P.
Published: November 2009

The rapid development of integrated circuit technology from small-scale integration (SSI) to very large scale integration (VLSI) has had great technological and economical impact on the electronics industry. The exponential growth of the number of components per IC chip, the exponential decrease of device dimensions, and the steady increase in IC chip size have imposed stringent requirements, not only on the IC physical design and fabrication, but also on IC encapsulants. This report addresses the purpose of encapsulation, encapsulation techniques, and a general overview of the application of inorganic and organic polymer materials as electronic device encapsulants.
Twist-Off Testing of Solder Joint Interconnections
Authors: Suhir E.
Published: November 2009

Twist-off testing of solder joint interconnections is regarded by many reliability engineers in the microelectronic industry as an attractive alternative to shear-off testing. In this paper we briefly discuss the merits and shortcomings of both techniques and determine the relationship between the ultimate torque and the ultimate shearing force. We also suggest a simple experimental method for the evaluation of the shearing strength of solder joints on the basis of twist-off testing. It should be emphasized that such testing can be used not only for a tentative comparative evaluation of different interconnections but as a quality control vehicle as well.
Thermal and Structural Analysis of a PLCC Device for Surface Mount Processes
Authors: Glaser J. C. , Juaire M. P.
Published: November 2009

Industy is concerned with reliability questions for surface mounted Plastic Encapsulated Chip Carrier (PLCC) devices and various aspects of the encapsulation and mounting process have been studied from a thermal and structural point of view. This paper reports on the results of a two-dimensional Finite Element Analysis (FEA) of a representative cross section of a typical PLCC undergoing surface mount soldering conditions. Results are presented for thermal and structural analyses of the numerical model for both a vapor phase and an infrared soldering process. The analyses show the thermal gradients resulting from the thermal processes in soldering and provides an understanding of the stress distribution in a PLCC during these processes. The thermal results indicate that temperature gradients within the PLCC do not appear to be severe during either process. The stress results confirm the importance of the stress-free reference temperature for the encapsulation material. The effect of some key process and device conditions is also discussed.
Thermally Conductive Ceramics for Electronic Packaging
Authors: Suryanarayana D.
Published: November 2009

A survey was conducted on the physical properties of several new ceramic systems, such as carbides, borides, oxides, and nitrides, as they appeared in recent literature, and they are briefly reviewed. A few new ceramic materials, such as BeO, BN, AlN, and SiC-BeO, possess superior thermal properties when compared to the alumina (Al2O3) ceramics used in electronic packaging. Among these, the aluminum nitride (AlN) has emerged as unique material that can replace alumina in future electronic packaging for improved thermal performance and reliability.
Experimental Modeling of Convection Downstream from an Electronic Package Row
Authors: Wirtz R. A. , McAuliffe W.
Published: November 2009

Experiments on convective heat transfer in the wake of a row of closely spaced pin-mount packages are reported. Flow visualization and interferometric heat transfer measurements are made in an induced draft wind tunnel where the package row is modeled with a two-dimensional transverse rib attached to one channel wall. The transverse rib has an aspect ratio of 5.25:1.0, and the channel height-to-rib height ratio is 4.0:1.0. Results are reported for coolant Reynolds numbers ranging from 1000 to 4000. Flow visualization shows the wake region to be similar to flow past a simple back step. Recirculating flow is found to extend from nine to three rib heights downstream from the rib, depending on the magnitude of the flow Reynolds number. Local heat transfer within this region is reduced relative to what would occur in the absence of the transverse rib, with average values of the heat transfer coefficient bracketed between laminar and turbulent correlations for simple back steps. Heat transfer rates further downstream, after reattachment of the flow, are in excess of those expected for flow with no transverse rib.
Convective Heat Transfer From Longitudinal Fin Arrays in the Entry Region of Turbulent Flow
Authors: Lau K. S. , Mahajan R. L.
Published: November 2009

Experiments were performed to study the heat transfer from longitudinal fin arrays in turbulent air flow in the combined hydrodynamic and thermal entry region of a rectangular channel. The thermal resistance of the fin arrays was measured for fin heights of 1 and 1.9 cm and for tip-clearances varying from 0 to 2 cm (i.e. clearance to height ratio varies from 0 to 2). Results indicate that, for a given mass flow rate, the thermal resistances for the two fin heights are close when the tip-clearance is zero. With a clearance of 2 cm, the thermal resistance increases by 85 percent in the short fins, and by 210 percent in the tall fins. Extending the concept of wetted perimeter, a heating diameter is proposed to define the Reynolds and Nusselt numbers. With these modified definitions, experimental data can be fit into a single correlation which is 42 percent higher than that proposed by Petukhov and Popov (1963) for smooth round pipes. A design equation is then derived to predict the effect of the tip-clearance on the heat transfer coefficient for fin arrays with different heights, spacings and thicknesses. Agreement has been found between the present prediction and past experimental results by Sparrow and Kadle (1986) with clearance to height ratio varying from 0 to 0.33.
Lead Frame and Wire Length Limitations to Bond Densification
Authors: Jahsman W. E.
Published: November 2009

At IC package lead counts above 100, the limiting factor for bond densification in single layer packages with gold wire interconnections shifts from pad pitch to a combination of lead tip pitch and wire length. To quantify this effect, the densification capabilities of four different lead frame designs were calculated for the 164 lead plastic quad flat pack (PQFP) and compared to the pad limited (i.e., non-lead frame/wire length constrained) design. Of the four, the orthogonal layout provided maximum densification although its die size was still almost 33 percent larger than that of the pad limited design. It also had the disadvantage of a large angle of attack between the wire and the lead tip orientations at second bond. At the other extreme, the die-centered radial layout assured zero angle of attack but required a 53 percent larger die than the pad-limited layout. The other two lead frame designs resulted in die sizes which fell between these limits, slightly above the orthogonal layout value. After consideration of factors such as densification, manufacturability and die size tolerance, it was concluded that the variable center, variable radius layout, which features constant bond pad pitch and wire length, offers the best densification opportunity for wire bonded products. For maximum (i.e., pad limited) densification to optimize die yields and performance, advanced interconnect technologies such as TAB (tape-automated bonding) will be required.
A Note on the Calculation of Thermal Stresses in Electronic Packaging by Finite Element Methods
Authors: Lau J. H.
Published: November 2009

The purpose of this paper is to point out a very common mistake made in determining the thermal stresses in composite structures by finite element methods. Furthermore, a simple technique to obtain the correct thermal stresses is recommended.
Effect of Sodium, Potassium, Magnesium, Calcium, and Chlorine on the High Temperature Corrosion of In-100, U-700, IN-792, and MAR M-509
Authors: Lowell C. E. , Sidik S. M. , Deadmore D. L.
Published: November 2009

The effects of potential impurities, such as Na, K, Mg, Ca, and Cl, in coal-derived liquid fuels on accelerated corrosion of IN-100, U-700, IN-792, and Mar M-509 were investigated using a Mach 0.3 burner rig for times to 200 hr in 1 hr cycles. These impurities were injected in combination as aqueous solutions into the combustor. Other variables were time, temperature, and fuel-to-air ratio. The experimental matrix was a central composite fractional factorial design divided into blocks to allow modification of the design as data was gathered. The extent of corrosion was determined by metal consumption, τ.
Redesign of Structural Vibration Modes by Finite-Element Inverse Perturbation
Authors: Stetson K. A. , Harrison I. R.
Published: November 2009

A previously developed technique for redesigning the vibrational properties of structures, by inverting the first-order perturbation analysis of the equations of motion, has been applied to a NASTRAN finite element analysis for plates and shells. The program finds the minimal changes to the thicknesses of the plate elements necessary to effect a given set of changes in the modal frequencies and shapes. Results have been obtained for a flat cantilever plate, a cantilever segment of a cylinder, and for a compressor blade for a jet engine.
Efficient Laser Anemometer for Intra-Rotor Flow Mapping in Turbomachinery
Authors: Powell J. A. , Strazisar A. J. , Seasholtz R. G.
Published: November 2009

Innovative features of the anemometer include: (1) a rapid and efficient data acquisition process, (2) a detailed real-time graphic display of the data being accumulated, and (3) input laser beam positioning that maximizes the size of the intra-rotor region being mapped. Results are presented that demonstrate the anemometer’s capability in flow mapping within a transonic axial-flow compressor rotor. Typically, a velocity profile, derived from 30,000 measurements along 1000 sequential circumferential positions covering 20 blade passages, can be obtained in 30 s. The use of fluorescent seed particles allows flow measurements near the rotor hub and the casing window.
Optical Advances in Laser Transit Anemometry
Authors: Smart A. E. , Wisler D. C. , Mayo W. T.
Published: November 2009

A Laser Transit Anemometer (LTA) system for measurement of velocity, flow angle and turbulence in the rotating blade rows of turbomachinery and for other applications has been developed by the authors (SDL). Advanced optical, electronic, and computer components make the system sensitive to submicron scatterers, provide automated data collection and permit probing close to blade and wall surfaces, in some cases without seeding the flow. This paper describes new and practical developments of the optical system and presents test results from axial compressor measurements. Based upon these test results, improvements were incorporated into the system and these improvements are discussed briefly.
Mean Flow Measurements Near the Plane of an Open Rotor Operating with an Inlet Velocity Gradient
Authors: Billet M. L.
Published: November 2009

As part of a study on the structure of a trailing vortex, laser doppler anemometer (LDA) measurements were made of the flow field near an open rotor having an inlet velocity gradient. The measurements were made in the 1.22 m dia water tunnel of the Applied Research Laboratory at The Pennsylvania State University. Velocity data were obtained for rotor inlet and outlet flow fields for several different inlet velocity gradients. Velocity data were also obtained downstream of the rotor plane that shows the vortex structure. Flow field measurements show the development of the downstream vortex motion. Small variations in the inlet velocity gradient near the rotor wall caused large differences in the structure of the trailing vortex. In addition, a measured downstream velocity profile is compared with a calculated velocity profile.
Laser-Optical Blade Tip Clearance Measurement System
Authors: Barranger J. P. , Ford M. J.
Published: November 2009

The need for blade tip clearance instrumentation has been intensified recently by advances in technology of gas turbine engines. A new laser-optical measurement system has been developed to measure single blade tip clearances and average blade tip clearances between a rotor and its gas path seal in rotating component rigs and complete engines. The system is applicable to fan, compressor and turbine blade tipe clearance measurements. The engine mounted probe is particularly suitable for operation in the extreme turbine environment. The measurement system consists of an optical subsystem, an electronic subsystem and a computing and graphic terminal. Bench tests and environmental tests were conducted to confirm operation at temperatures, pressures, and vibration levels typically encountered in an operating gas turbine engine.
Heat Transfer Downstream of a Leading Edge Separation Bubble
Authors: Bellows W. J. , Mayle R. E.
Published: November 2009

Experiments for flow about a two-dimensional blunt body with a circular leading edge are described. Measurements of the free-stream and boundary-layer velocity distributions are presented and indicate that a small separation “bubble” existed where the leading edge joined the body. In particular, it was found that the laminar leading edge boundary layer separated and reattached shortly downstream as a turbulent boundary layer with a low-momentum thickness Reynolds number. Heat transfer measurements around the body are also presented and show almost an order of magnitude increase across the bubble. Downstream of the bubble, however, the heat transfer could be correlated by a slightly modified turbulent flat plate equation using the separation point as the virtual origin of the heated turbulent boundary layer.
Through-Flow Analysis of a Multistage Compressor: Part I—Aerodynamic Input
Authors: Dring R. P. , Joslyn H. D.
Published: November 2009

Through-flow theory is at the heart of turbomachinery aerodynamic design in that it provides the incidence and Mach number distributions that are ultimately used to define the rotor and stator airfoil contours. The assumption of axisymmetry plays a major role in the formulation of the theory and the consequences of this assumption have historically necessitated the introduction of “blockage” to account for the nonaxisymmetries in the flow. The present paper provides an assessment of these assumptions and of through-flow theory in general by making detailed comparisons between computed and measured results for a two-stage axial compressor. Part I focuses on the experimental benchmark data base and on how these data were used to fully define all of the aerodynamic input required by a through-flow analysis.
Comparison of Calculated and Experimental Cascade Performance for Controlled-Diffusion Compressor Stator Blading
Authors: Sanger N. L. , Shreeve R. P.
Published: November 2009

The midspan section of a previously reported controlled-diffusion compressor stator has been experimentally evaluated in cascade. Measurements were taken over a range of incidence angles for blade chord Reynolds numbers from 470,000 to 690,000. Blade chord length was 12.7 cm, aspect ratio was 2.0, and solidity was 1.67. Measurements included conventional cascade performance parameters as well as blade surface pressures. Computations were made for the inviscid flow field, surface boundary layers, and loss for several of the blade inlet angle conditions, and compared against corresponding data.
Performance of Axial Compressor With Nonuniform Exit Static Pressure
Authors: Kodama H.
Published: November 2009

An analytical model has been developed to predict the performance of axial compressors with an exit static pressure perturbation. The model uses a two-dimensional compressible semi-actuator disk model. This method can be applied to the compressor with known circumferential variation in exit static pressure which is measured or predicted by an analytical method. The analytical results are found to be in good agreement with experiments carried out on two transonic fans.
Predictive Surge Control and Optimization for a Centrifugal Compressor
Authors: Patlovany D. , Focke A. B.
Published: November 2009

This paper details the installation of a retrofit supervisory control system on a large air compressor for the purpose of minimizing energy costs and protecting the compressor from surge. The paper discusses how an accurate prediction of the compressor’s stable operating region can be calculated to develop a compressor performance “map” and how this map can then be used to cut energy consumption by the compressor driver. The compressor is protected from surging by a “predictive” control method. Instead of waiting for the compressor to surge, and then reacting, the system calculates when surge is about to occur and takes action to avoid a surge event before it occurs. The installation of a control system of this type can result in a substantial dollar savings in energy costs, while guaranteeing that a compressor will be protected from any damage from a severe surge event. This system has been installed in our plant and proven in practice. The paper details the installation of this system and its results.
A Model for Closing the Inviscid Form of the Average-Passage Equation System
Authors: Adamczyk J. J. , Mulac R. A. , Celestina M. L.
Published: November 2009

A mathematical model is proposed for closing or mathematically completing the system of equations which describes the time-averaged flow field through the blade passages of multistage turbomachinery. These equations, referred to as the average-passage equation system, govern a conceptual model which has proven useful in turbomachinery aerodynamic design and analysis. The closure model is developed so as to insure a consistency between these equations and the axisymmetric through-flow equations. The closure model was incorporated into a computer code for use in simulating the flow field about a high-speed counterrotating propeller and a high-speed fan stage. Results from these simulations are presented.
The Aerodynamic Development of a Highly Loaded Nozzle Guide Vane
Authors: Baines N. C. , Oldfield M. L. G. , Simons J. P. , Wright J. M.
Published: November 2009

A series of high-pressure turbine nozzle guide vanes has been designed for progressively increasing blade loading and reduction in blade solidity without additional loss penalty. Early members of the series achieved this by changes to the suction surface contour, but for the latest design the pressure surface contour was extensively modified to reduce the velocities on this surface substantially. Cascade testing revealed that this vane had a higher loss than its predecessor, and this appears to be largely due to a long region of boundary layer growth on the suction surface and possibly also an unsteady separation. These tests demonstrated the value of a flattened pitot tube held against the blade surface in determining the boundary layer state. By using a pitot probe of only modest frequency response (of order 100 Hz) it was possible to observe significant qualitative differences in the raw signals from laminar, transitional and turbulent boundary layers, which have previously been observed only with much higher frequency instruments. The test results include a comparison of boundary layer measurements on the same cascade test section in two different high-speed wind tunnels. This comparison suggests that freestream turbulence can have a large effect on boundary layer development and growth.
A New Experimental Technique to Simulate Secondary Erosion in Turbine Cascades
Authors: Singh P. J. , Dussourd J. L.
Published: November 2009

In refineries, power-recovery turbines are widely used in the fluid catalytic cracking process to extract power from particle-laden gases. The gas particles impinging on the blades cause blade and platform erosion. This erosion can be broadly classified into primary and secondary erosion according to the dynamics of the particle/flow interactions and whether the damage is caused by direct inertial impingement or by recirculation of fine particles (1–2 μm) through the blade secondary flows, by the vortices induced by these flows. This paper reports on a new experimental method devised to simulate the secondary erosion patterns without the use of a dust-laden stream. In this method, blades coated with a sublimating material such as naphthalene are tested in a wind tunnel. The secondary flow vortices tend to increase the local rate of sublimation in those areas where surface momentum gradients are high. This simulates the condition of preferential erosion induced by the dust loading present in the vortices. Tests show the induced patterns to be quite akin to secondary erosion seen on field run blades especially in the critical erosion patterns seen near the blade roots. Design modifications were then successfully developed to minimize this secondary erosion. These were shown to have a capability of reducing the erosion by 50 to 75 percent, by utilizing platform step control and naturally induced boundary layer suction. Conversely, many other features were found surprisingly ineffective. The method was also shown to be a very effective surface flow visualization technique for internal and external surfaces. Of the approaches found to be successful in minimizing erosion damage, control of the geometry of the stator to rotor steps along the hub flow path blade platforms was critical. Steps in general have the effect of making erosion worse. The most successful approach is the introduction of an inherent suction slot and the suction flow passage between individual blade platforms.
Blade Design of Axial-Flow Compressors by the Method of Optimal Control Theory—Application of Pontryagin’s Maximum Principles, a Sample Calculation and Its Results
Authors: Gu Chuan-gang , Miao Yong-miao
Published: November 2009

Using the continual transformation technique [3] and the augmented penalty function method, the typical optimal control problem with various constraints proposed in the paper [2] has been converted to a new equivalent optimal control problem with no constraint. This enables the application of Pontryagin ’s maximum principle. Further, by means of the conjugate gradient method an example of the calculation is shown and the corresponding program is developed. A satisfactory optimal diffusion factor distribution has been obtained.