bluuebunny/crossref_metadata_2025 huggingface dataset:
Measuring How Administration Shapes Citizenship: A Policy Feedback Perspective on Performance Management
Authors: Wichowsky Amber , Moynihan Donald P.
Published: August 2008

Governments increasingly require administrators to develop outcome measurements that reflect a program’s impact on society. But standard approaches to performance measurement have neglected the impact on citizenship outcomes—the individual civic capacities and dispositions and social bonds of civic reciprocity and trust. The concept is adapted from the growing policy feedback literature in political science, which offers strong empirical evidence that certain policies have measurable effects on citizenship outcomes such as political participation, social capital, a sense of civic belonging, and self‐worth as a citizen. Using the Program Assessment Rating Tool as an example, the authors demonstrate the failure of performance assessments to consider the civic implications of public policies. They argue that performance management systems should focus on citizenship outcomes and offer a series of suggestions on how to measure such outcomes.
Human NK cells: from HLA class I‐specific killer Ig‐like receptors to the therapy of acute leukemias
Authors: Moretta Alessandro , Locatelli Franco , Moretta Lorenzo
Published: August 2008

Summary: Over the past 20 years, major progress has been made in our understanding of natural killer (NK) cells. It has become clear that NK cells are regulated by a number of receptors with opposite functions that finely tune potent effector functions such as cytolytic activity and release of cytokines that play a major role in inflammation and immunoregulation. This review traces the major advances in human NK cell biology from the original discovery of human leukocyte antigen class I‐specific inhibitory receptors to recent groundbreaking clinical applications. These, in turn, led to major achievements and further expectations in the cure of high risk of otherwise fatal leukemias. It has become evident that there is a role of donor‐derived ‘alloreactive’ NK cells in eradicating acute myeloid (and now also lymphoid) leukemias in the T‐cell‐depleted haploidentical hemopoietic stem cell transplantation setting. The key role played also in preventing graft rejection and graft versus host disease renders alloreactive NK cells an ideal tool for successful haploidentical hematopoietic stem cell transplantation.
Mobilization of Bone Marrow Cells by Leukocytapheresis in Patients With Ulcerative Colitis
Authors: Mitsuyama Keiichi , Andoh Akira , Masuda Junya , Yamasaki Hiroshi , Kuwaki Kotaro , Takedatsu Hidetoshi , Seki Ritsuko , Nishida Hidemi , Tsuruta Osamu , Sata Michio
Published: August 2008

Abstract:  While several trials have suggested that leukocytapheresis by filtration can benefit patients with active ulcerative colitis (UC), mechanisms underlying these benefits are largely unknown. We studied how leukocytapheresis mobilizes bone marrow cells into the peripheral circulation in patients with active UC. Leukocytapheresis transiently reduced peripheral leukocytes, followed by an overshoot increase with emergence of immature leukocytes. The numbers of colonies and CD34+ cells were comparable between UC patients and normal controls. Shortly after leukocytapheresis, the numbers of both colonies and CD34+ cells increased significantly in UC patients (P < 0.0001 and P = 0.0372, respectively). This was not associated with changes in the concentration of circulating cytokines or epinephrine. These results indicate that leukocytapheresis mobilizes bone marrow cells into the circulation. This cell replacement may partly explain the therapeutic benefit in UC. The functional role of the mobilized bone marrow cells in affected intestine remains to be characterized.
Proliferating Potential and Apoptosis in the Development of Secondary Hyperparathyroidism: A Study Based on Ki‐67 Immunohistochemical Staining and the Terminal dUTP Nick‐End Labeling Assay
Authors: Wada Yukihiro , Kunimura Toshiaki , Sato Shun , Hisayuki Tomokazu , Sato Masashi , Imataka Hiromi , Yamashita Norimasa , Akizawa Tadao , Moroboshi Toshio
Published: August 2008

Abstract:  Secondary hyperparathyroidism (SHPT) is a common complication in hemodialysis (HD) patients. SHPT progresses from initial diffuse hyperplasia (diffuse) to early nodularity (early), then to multinodular hyperplasia (nodular), and finally to a single nodule (single) consisting of uniform parenchymal cells. We analyzed the roles of proliferation and apoptosis in SHPT progression. Seventy‐four parathyroid glands from 36 HD patients with SHPT, and 10 parathyroid glands from 10 non‐HD patients without SHPT were used for analysis. The former were classified as diffuse (N = 17), early (N = 22), nodular (N = 20), and single (N = 15); the latter were classified as normal (N = 10). To analyze proliferating cells we used Ki‐67, and to detect apoptotic cells, we used the terminal deoxynucleotidyl transferase (Tdt)‐mediated dUTP nick‐end labeling (TUNEL) assay. Concerning the Ki‐67 labeling index (LI), the incremental order was single, nodular, early, diffuse, and normal. Oxyphilic cells and around the central portion of each lesion were distinctly stained by Ki‐67. Concerning the TUNEL LI, the incremental order was early, diffuse, nodular, single, and normal. Chief cells and around the peripheral portion of each lesion were distinctly stained by TUNEL. In the progression from early to nodular, for oxyphilic cells, the Ki‐67 LI increased and the TUNEL LI decreased; for chief cells, the Ki‐67 LI decreased and the TUNEL LI showed no significant change. We considered that proliferative activity increases and that the apoptosis rate decreases as SHPT progresses from diffuse to single. Moreover, the specific differences in the rate of proliferation and apoptosis between oxyphilic and chief cells might be associated with SHPT progression.
A Case Report of Pediatric Fulminant Hepatitis Treated With Plasma Diafiltration
Authors: Nakae Hajime , Igarashi Toshiko , Tajimi Kimitaka , Noguchi Atsuko , Takahashi Ikuko , Tsuchida Satoko , Takahashi Tsutomu , Asanuma Yoshihiro
Published: August 2008

Abstract:  Plasma diafiltration (PDF) is blood purification therapy in which simple plasma exchange is performed with a membrane plasma separator while dialysate flows outside the hollow fibers. A 14‐year‐old boy with fulminant hepatitis underwent two sessions of PDF and one session of hemodiafiltration. We infused filtered replacement fluid for artificial kidneys at a dialysate flow rate of 600 mL/h and a replacement flow rate of 450 mL/h. We infused fresh frozen plasma (1200 mL) and 25% albumin solution (50 mL) intravenously over 8 h. Each PDF session lasted 8 h. The patient's total bilirubin, interleukin‐18, and cystatin C levels decreased with treatment, and he recovered from hepatic failure. PDF may be an extremely useful blood purification therapy for pediatric fulminant hepatitis in terms of both medical economics and cytokine removal.
Physician perceptions of nurse practitioners: A replication study
Authors: Running Alice , Hoffman Lisa , Mercer Victoria
Published: August 2008

Purpose: To replicate and update findings from an earlier study on the perceived incentives of physicians to work with nurse practitioners (NPs).

Data sources: Four hundred and three questionnaires were mailed to NPs who distributed them to their collaborating physicians.

Conclusion: Physicians ranked “accessibility to health care” and the “quality of care” as equally important and more important than “physician satisfaction” and “economic incentives.” The findings were consistent with findings from the earlier study; however, the original study demonstrated a much clearer distinction among the four groups of incentives.

Implications for practice: These findings imply that collaboration between physicians and NPs is maturing as NPs move into more arenas in health care.
Smoking cessation readiness: Are your patients ready to quit?
Authors: Woody Delinda , DeCristofaro Claire , Carlton Betty G.
Published: August 2008

Purpose: To explore the assessment of patient readiness to receive smoking cessation interventions using the transtheoretical model (TTM) and the five stages of change; and to give the primary care provider an evidence‐based toolkit to assist in evaluating for readiness and supporting the smoking cessation process.

Data sources: Evidence‐based literature, theoretical framework, and peer‐reviewed articles.

Conclusions: Utilizing the TTM along with proper training and education of the provider and patient increases the probability that smoking cessation will occur. Combinations of pharmaceutical and nonpharmaceutical interventions are the most effective in smoking cessation.

Implications for practice: Providers can be prepared at every patient visit to address the smoking cessation needs of all patients. The toolkit provided in this article will help facilitate evaluation of readiness and support of effective, long‐term smoking cessation and reduce eventual smoking‐related morbidities.
Aortic stenosis in the Dogue de Bordeaux
Authors: Höllmer M. , Willesen J. L. , Jensen A. T. , Koch J.
Published: August 2008

Objectives:To evaluate the occurrence of aortic stenosis and establish echocardiographic reference values in the Dogue de Bordeaux in Denmark.

Methods:Fifty‐three dogs were auscultated for evidence of a cardiac murmur and a full echocardiographic examination was performed. The criterion for the diagnosis of aortic stenosis was a peak aortic velocity greater than 2·5 m/s from a subcostal transducer location.

Results:A left‐basilar ejection murmur was detected in 38 (72 per cent) of the dogs. An aortic ejection velocity greater than 2·5 m/s was identified in 9 (17 per cent) of the dogs from a subcostal view. The aortic annulus in Dogue de Bordeaux was smaller than that considered normal in other breeds with comparable body size. Furthermore, a decreased aortoseptal angle was noticed in dogs with aortic stenosis.

ClinicalSignificance:The Dogue de Bordeaux may be highly predisposed to aortic stenosis. The small aortic annulus noted in healthy and affected Dogue de Bordeaux and a decreased aortoseptal angle noted in affected dogs in this study might reflect key aetiological features in the development of aortic stenosis.
Cryohypophysectomy used in the treatment of a case of feline acromegaly
Authors: Blois S. L , Holmberg D. L
Published: August 2008

A 10‐year‐old female spayed cat was diagnosed with acromegaly secondary to a pituitary tumour. At the time of diagnosis, the cat had insulin‐resistant diabetes mellitus and its insulin‐like growth factor‐I levels were elevated. Clinical signs included polyuria, polydipsia and weight gain. Persistent hyperglycaemia and glucosuria were identified, and fructosamine levels remained elevated. Magnetic resonance imaging of the brain showed a pituitary tumour. Transsphenoidal cryohypophysectomy was used to treat the pituitary tumour. Postoperatively, the serum insulin‐like growth factor‐I levels decreased and the diabetes mellitus was controlled with routine levels of insulin. To the authors’ knowledge, this is the second reported case of acromegaly treated with cryohypophysectomy, and the first that reports a favourable long‐term outcome. Cryohypophysectomy may be a safe and effective treatment for cats with a pituitary mass resulting in acromegaly.
Blindness as a sign of proventricular dilatation disease in a grey parrot (Psittacus erithacus erithacus)
Authors: Steinmetz A. , Pees M. , Schmidt V. , Weber M. , Krautwald‐Junghanns M.‐E. , Oechtering G.
Published: August 2008

An approximately eight‐year‐old female grey parrot (Psittacus erithacus erithacus) was presented with a two months history of blindness. The radiographic examination showed a dilatation of the proventriculus, ventriculus and gut. Ophthalmoscopy and electroretinography revealed degeneration of the retina. A proventricular dilatation disease was suspected. The bird was euthanased because of deteriorating condition and poor prognosis. The pathological examination showed an atrophy of the ventricular muscles and lymphoplasmacytic infiltrates of the myenteric plexus of the proventriculus, ventriculus and gut as well as moderate lymphoplasmacytic infiltrates of the cerebrum with moderate neuronophagia. Lymphoplasmacytic infiltrates in the retina, indicating proventricular dilatation disease, and subsequent retinal degeneration were found. A potential common aetiology for proventricular dilatation disease and blindness is discussed.
Comparison of magnetic resonance imaging sequences in dogs with multi‐focal intracranial disease
Authors: Cherubini G. B. , Platt S. R. , Howson S. , Baines E. , Brodbelt D. C. , Dennis R.
Published: August 2008

Objectives: To compare the value of different magnetic resonance sequences in the detection of brain lesions in dogs with multi‐focal intracranial neurolocalised lesions and abnormal cisternal cerebrospinal fluid analysis.

Methods: T2‐weighted, T1‐weighted, T1‐weighted‐Gd, FLAIR (fluid attenuated inversion recovery) images of 73 dogs with multi‐focal intracranial localised lesions were reviewed retrospectively. Control dogs (19) were selected on the basis of normal neurological examination, magnetic resonance images and cerebrospinal fluid analysis. Two board‐certified radiologists blindly reviewed the magnetic resonance images. Magnetic resonance sequence sensitivities were compared using the chi‐squared test and logistic regression, accounting for clustering at the patient level. Statistical significance was set at the 5 per cent level.

Results: The FLAIR sequence was found to have the highest sensitivity (84 per cent, 61 of 73), followed by T2‐weighted (63 per cent, 46 of 73), T1‐weighted postcontrast (62 per cent, 45 of 73) and T1‐weighted (23 per cent, 17 of 73) (P<0·001). FLAIR images were 106·1 times (95 per cent confidence interval 25·2 to 447·5) more likely to correctly identify cerebrospinal fluid‐positive patients than T1‐weighted, 6·4 times (95 per cent confidence interval 2·2 to 18·2) than T1‐weighted postcontrast and 5·8 times (95 per cent confidence interval 2·0 to 16·4) than T2‐weighted. FLAIR identified 14 per cent of cases that were classified as normal based on the three others sequences.

Clinical Significance: Routine use of FLAIR sequence should be encouraged in dogs undergoing a brain magnetic resonance imaging and probably more specifically in cases of suspected inflammatory brain disease.
Effects of Hole Arrangements on Local Heat/Mass Transfer for Impingement/Effusion Cooling With Small Hole Spacing
Authors: Cho Hyung Hee , Rhee Dong Ho , Goldstein R. J.
Published: August 2008

The present study investigates the local heat (mass) transfer characteristics of flow through perforated plates. Two parallel perforated plates were placed, relative to each other, in either staggered, in line, or shifted in one direction. Hole length to diameter ratio of 1.5, hole pitch to diameter ratio of 3.0, and distance between the perforated plates of 1–3 hole diameters are used at hole Reynolds numbers of 3000 to 14,000. For flows through the staggered layers and the layers shifted in one direction, the mass transfer rates on the surface of the effusion plate increase approximately 50% from impingement cooling alone and are about three to four times that with effusion cooling alone (single layer). The high transfer rate is induced by strong secondary vortices formed between two adjacent impinging jets and flow transition so that heat/mass transfer coefficient in the midway region is as high as stagnation heat/mass transfer coefficient. The mass transfer coefficient for the in-line arrangement is approximately 100% higher on the target surface than that of the single layer case. In overall, the staggered hole arrangement shows better performance than other cases.
Mixed Flow Turbine Research: A Review
Authors: Rajoo Srithar , Martinez-Botas Ricardo
Published: August 2008

Research on mixed flow turbines spans over 50years with substantial literature available in the public domain. Mixed flow turbines were initially used as an alternative rotor design for gas turbines and later extended to automotive turbocharger applications. The characteristics of a mixed flow turbine resemble a radial turbine but with some significant performance improvements, giving this design an edge to satisfy the ever increasing demand in the automotive sector. The initial research focus was mainly experimental but in recent years, there have been significant contributions in computational analysis. This paper is intended to provide readers with a comprehensive review of the past and present research into the design, performance, and use of mixed flow turbines. Additionally, the future research direction of the mixed flow turbine is discussed in view of the current turbocharger and automotive demand.
Periodical Unsteady Flow Within a Rotor Blade Row of an Axial Compressor—Part II: Wake-Tip Clearance Vortex Interaction
Authors: Mailach Ronald , Lehmann Ingolf , Vogeler Konrad
Published: August 2008

In this two-part paper, results of the periodical unsteady flow field within the third rotor blade row of the four-stage Dresden low-speed research compressor are presented. The main part of the experimental investigations was performed using laser Doppler anemometry. Results of the flow field at several spanwise positions between midspan and rotor blade tip will be discussed. In addition, time-resolving pressure sensors at midspan of the rotor blades provide information about the unsteady profile pressure distribution. In Part II of the paper, the flow field in the rotor blade tip region will be discussed. The experimental results reveal a strong periodical interaction of the incoming stator wakes and the rotor blade tip clearance vortices. Consequently, in the rotor frame of reference, the tip clearance vortices are periodical with the stator blade passing frequency. Due to the wakes, the tip clearance vortices are separated into different segments. Along the mean vortex trajectory, these parts can be characterized by alternating patches of higher and lower velocities and flow turning or subsequent counter-rotating vortex pairs. These flow patterns move downstream along the tip clearance vortex path in time. As a result of the wake influence, the orientation and extension of the tip clearance vortices as well as the flow blockage periodically vary in time.
Transition on the T106 LP Turbine Blade in the Presence of Moving Upstream Wakes and Downstream Potential Fields
Authors: Opoka Maciej M. , Hodson Howard P.
Published: August 2008

Boundary layer measurements were performed on a cascade of the T106 high lift low-pressure (LP) turbine blades that was subjected to upstream wakes and a moving downstream potential field. Tests were carried out at a low level of inlet freestream turbulence (0.5%) and at a higher (4.0%). It is found that perturbations in the freestream due to both disturbances are superposed on each other. This affects the magnitude of the velocity perturbations at the edge of the boundary layer under the wakes as well as the fluctuations in the edge velocity between the wakes. Furthermore, the fluctuations in the adverse pressure gradient on the suction surface depend on the relative phase of the upstream and downstream disturbances, providing an additional stimulus for clocking studies. Time-mean momentum thickness values calculated from laser Doppler anemometry (LDA) traverses performed near the suction surface trailing edge are used to identify the optimum relative phase angle of the combined interaction. Unsteady suction surface pressures, quasiwall shear stress and LDA data illustrate the resulting multimode process of transition, which is responsible for the observed clocking effects. The optimum relative phase angle of the upstream wake and the downstream potential field can produce 0.25% of efficiency improvement through the reduction of the suction surface boundary layer loss. This reduction is mainly related to the calmed region and the laminar flow benefits that can be more effectively utilized than when only the upstream wakes are present. During the remaining parts of the cycle, the features that are usually associated with the wake and the potential field effects are still present.
Bump and Trench Modifications to Film-Cooling Holes at the Vane-Endwall Junction
Authors: Sundaram N. , Thole K. A.
Published: August 2008

The endwall of a first-stage vane experiences high heat transfer and low adiabatic effectiveness levels because of high turbine operating temperatures and formation of leading edge vortices. These vortices lift the coolant off the endwall and pull the hot mainstream gases toward it. The region of focus for this study is the vane-endwall junction region near the stagnation location where cooling is very difficult. Two different film-cooling hole modifications, namely, trenches and bumps, were evaluated to improve the cooling in the leading edge region. This study uses a large-scale turbine vane cascade with a single row of axial film-cooling holes at the leading edge of the vane endwall. Individual hole trenches and row trenches were placed along the complete row of film-cooling holes. Two-dimensional semi-elliptically shaped bumps were also evaluated by placing the bumps upstream and downstream of the film-cooling row. Tests were carried out for different trench depths and bump heights under varying blowing ratios. The results indicated that a row trench placed along the row of film-cooling holes showed a greater enhancement in adiabatic effectiveness levels when compared to individual hole trenches and bumps. All geometries considered produced an overall improvement to adiabatic effectiveness levels.
Inner-Loop Control for Electromechanical (EMA) Flight Surface Actuation Systems
Authors: Habibi Saeid , Roach Jeff , Luecke Greg
Published: August 2008

This manuscript pertains to the application of an inner-loop control strategy to electromechanical flight surface actuation systems. Modular electromechanical actuators (EMAs) are increasingly used in lieu of centralized hydraulics for the control of flight surfaces in the aerospace sector. The presence of what is termed as a dead zone in these actuators significantly affects the maneuverability, stability, and the flight profiles of aircrafts that use this actuation concept. The hypothesis of our research is that flight surface actuation systems may be desensitized to the effects of dead zone by using a control strategy with multiple inner loops. The proposed strategy involves (a) high-gain inner-loop velocity control of the driving motor and (b) inner-loop compensation for the differential velocity between the motor versus the aileron. The above hypothesis is confirmed by theoretical and simulated analyses using the model of an EMA flight surface actuator. Our results indicate that for small input signals, this strategy is very effective and that it can (a) considerably increase the bandwidth and the crossover frequency of the system and (b) considerably improve the time response of the system. Further to this analysis, this manuscript presents guidelines for the design of EMA systems.
Servocontrol of the GS16 Turbine Gas Metering Valve by Physics-Based Robust Controller Synthesis
Authors: Shahroudi Kamran E. , Young Peter M.
Published: August 2008

We present a design approach for robust controller synthesis using a μ-synthesis procedure, which returns a controller in an observor/state-feedback form with physically meaningful states. We are also able to (approximately) retain this physical meaning when using balanced truncation to (significantly) reduce the controller order, as is often necessary in practice. The advantages of this physics-based approach are illustrated by a detailed outline of the controller design for Woodward Governor’s GS16 Turbine Gas Metering Valve.
Piping Fluid Transients Made Simple: Part I — Theory of the SSFFC Methodology
Authors: Ibrahim Zakaria N.
Published: August 2008

Piping systems transporting fluid between plant components are subjected to a variety of anticipated and/or postulated flow changes that disturb their steady state operations. These changes cause the fluid flow to accelerate and/or decelerate. However, consideration of fluid elasticity transforms these disturbances into weak and/or strong propagating sound waves, depending upon the abruptness level of the fluid state change. This generates dynamic forces on the pipe segments of the piping system. A simple concept for understanding the piping fluid transient phenomenon from its physical perspective is presented. The piping system consists of several pipe segments, each segment having a constant cross-sectional flow area. The pipe segment is further divided into a consecutive series of zones. Each zone comprises two or three sub-zones of quasi steady state flow. The sub-zones are separated by interface fronts at which the jump in fluid pressure and velocity occurs across them. These fronts propagate and clash with each other to create the next temporal set of sub-zones quasi steady state flow. This method is denoted in this paper as steady state flow fronts clashing ‘SSFFC’. Clashing between the incident, transmitted and/or reflected wave fronts within the zone is introduced. As a precursor to the second part of a two-part publication, the SSFFC is physically illustrated and mathematically formulated to establish the temporal fluid steady state contained within each sub-zone constituting the pipe segment. The developed formulations are comparable to those instituted by the conventional method of characteristics. The pipe segment generalized fluid flow transient forces based on SSFFC methodology are also formulated. In the concurrent publication that forms part two of this presentation [8], sample applications of SSFFC methodology are illustrated.
A 12 MM/S RMS Screening Vibration Velocity for Pipes Using ANSI-OM3 Standard and Regulatory Design Rules
Authors: Caillaud Se´bastien , Pons Yannick , Moussou Pierre , Gaudin Michae¨l
Published: August 2008

ASME ANSI-OM3 standard is dedicated to the assessment of piping vibrations for nuclear power plants. It provides an allowable zero-to-peak velocity, which is derived from a stress/velocity relationship, where corrections factors (C1, C2K2, C3, C4 and C5) and an allowable stress σal are introduced. In the ANSI-OM3 standard, the C4 correction factor depends on the pipe layout and on its boundary conditions, and is calculated for a few cases. In a former work, it was proposed to extend this factor to a larger number of pipe setups. Besides, the correction factor C1, which stands for the effect of concentrated mass, is established on a given set-up: a clamped-clamped straight pipe span on its first vibrating mode. C1 is then supposed to be conservative on any piping layout. Finally, allowable velocities derived from the ANSI-OM3 stress/velocity relationship may be very conservative. One way to reduce this conservatism is to introduce regulatory design rules. For a larger set of pipe geometries, a new set of C1 and C4 correction factors are computed using weight and pressure designs. Using these numerical results, allowable velocities can be calculated. Then, we propose here to check if a screening vibration velocity of 12 mm/s rms is fulfilled. For the 181 geometries on 3708, which do not meet the criterion, a seismic design checking is applied. Finally, by this way, 99.7% of the tested geometries, which are supposed to be acceptable with respect to static and seismic designs, display allowable velocities above 12 mm/s rms and the minimum allowable vibration velocity is 11.2 mm/s. This screening vibration velocity of 12 mm/s commonly used for vibration monitoring of piping systems in EDF nuclear power plants is then supported.
Double-Jacketed Gaskets for Heat Exchangers Sealability Behavior in Flanges With and Without Nubbin
Authors: Veiga Jose´ Carlos , Kavanagh Nelson
Published: August 2008

Due to their large size, double-jacketed gaskets used in shell and tube heat exchangers are manufactured by radial bending of pre-fabricated jacketed strip and joined by butt-welding of the metal jacket ends. This paper reports the results of a study to show the sealability behavior of the butt-welded DJ gaskets and their joint resistance, when installed in flanges with and without nubbin varying the seating stress.
A Reactor Vessel Upper Head Temperature Reduction Program at South Texas Units 1 and 2
Authors: Forsyth David R. , Lindenberg Steven C. , Klanica Frank , Strauch Pat L. , Patil Ulhas , Dubey Satish
Published: August 2008

One result of the replacement steam generator program at South Texas Units 1 and 2 was an increased core flow at the units above the desired values. In order to reduce the core flow and reduce the sensitivity of the Alloy 600 reactor vessel closure head penetrations to primary water stress corrosion cracking (PWSCC), a reactor vessel upper head temperature reduction (UHTR) program was performed at the units. The UHTR program is a field modification which results in a significant reduction in the reactor vessel head temperature by reducing the bulk fluid temperature in the upper head region of the reactor. This is accomplished by providing additional bypass flow to the upper head region from the vessel downcomer which lowers the region’s temperature. The modification, with its increased bypass flow, also reduces the core flow to acceptable levels. Lowering temperatures in the head penetrations can be an effective way to increase the time for crack initiation, reduce the rate of crack propagation and to extend the useful life of the original reactor vessel head and/or the life of a replacement head. This paper discusses the UHTR field modifications performed at South Texas Units 1 and 2, the reduction in core flow realized, the results of the modification to reduce the plant’s susceptibility to Alloy 600 head penetration cracking and the significant extension to the reactor vessel head life with the implementation of a UHTR program.
Comparative Study for Stresses in Nozzle and Flange Welds Generated During Conventional Pressure Testing and Local Pressure Testing Using Bolted Devices
Authors: Cheta Ayman M. , Brodzinski Richard
Published: August 2008

Weld repairs and alterations of pressure vessels and piping built to ASME codes may require pressure testing to prove the integrity of the weld and/or design. In recent years, several designs were developed to employ bolted devices when performing local pressure testing of flange-to-nozzle, flange-to-pipe and nozzle-to-shell attachment welds. Due to the cost and equipment down time associated with performing a full conventional pressure test and the desire to reduce repair costs, several petrochemical companies adopted the use of such devices. The purpose of this paper is to compare the stress values and stress distribution associated with both techniques. The advantages and disadvantages of both approaches are discussed and the conclusions are supported by a practical example.
The Formulations of Shear Force and Overturning Moment of the Large-Upright-Unanchored Industrial Liquid Storage Tanks Subjected to Horizontal Ground Excitations
Authors: Ozer Mutlu
Published: August 2008

The dynamic response analysis is performed for the formulations of shear force and overturning moment of the large-upright-unanchored industrial liquid storage tanks subjected to horizontal ground acceleration. As the tank is accelerated in the horizontal direction, it tends to uplift from its foundation, and hydrodynamic pressures on the tank wall vary with height in non-linear fashion. In this study, the distribution of hydrodynamic pressures and its center are directly correlated to formulate shear force and overturning moment. Initially, the equations of shear force and overturning moment derived by assuming hydrodynamic pressures exerted on tank wall vary in parabolic trend. Then derived equations are multiplied by dynamic coefficients, which are basically the function of peak ground acceleration, excitation frequency and the ratio of liquid’s height to radius of tanks. Dynamic coefficients are formulated through the shake table experiment of the model tanks excited by computer generated ground motion. The equations proposed in this paper for base shear and overturning moment are only the function of total weight of tank, the ratio of liquid’s height to radius, specific weight of liquid and dynamic coefficients for shear force and overturning moment. Therefore, proposed equations are very simple, efficient and easy to perform in calculating of shear forces and overturning moments of the large-upright industrial liquid storage tanks subjected to lateral earthquake loads. The results are verified with different codes (e.g. Eurocode8, API and AWWA-100...).
Development of the New Generation Materials for the Soft Pipe Lining Rehabilitation
Authors: Yu Hsin Her , Cheng Min-Hsun , Jou Rong-Yuan , Lee Kuang-Chyi , Lin Chien-Chang
Published: August 2008

With increasing global urbanization and industrialization, many more pipelines for gas, potable water, sewer, oil, and power cables have been installed underground, underwater, in buildings and in factories. Maintenance of such pipelines is crucial. However, it is often difficult and has become a growing problem these days. The PALTEM-HL (Trade mark and stands for Pipeline Automatic Lining SysTEM, Hose Lining Method), a pipeline relining system, was developed as an effective and inexpensive solution for this problem. In this project, we try to develop a new resins and the adhesives system to replace the raw materials used in the PALTEM-HL system. Anionic harder combined two different types of epoxy resins were investigated in this study. After curing, the mechanical properties and glass transition temperature of the mixture were examined and the optimum sample preparation prescription was also found. FTIR (Fourier Transform Infrared Spectroscopy) and DSC (Differential Scanning Calorimeter) were employed to monitor the curing process of the mixtures. The mechanical properties of the mixture were also measured by Instron and micro Vickers.
Structural Model of TLCD and Its Application
Authors: Chen Yung-Hsiang , Ko Chia-Hao , Ding Ying-Jan
Published: August 2008

A proposed mass-coupling structural mechanism is presented in this paper to represent a TLCD attached to a main structural system. It is a simple structural model and can be applied to the structural analysis of any complicate structure by use of the finite element method. The effectiveness of a passive or active TLCD in vibrational reduction of a five-story shear building subjected to earthquake is included as an example for demonstration and discussion.
Fundamental Interrelation Between Real and Imaginary Energies and Their Interrelation With Blade Angles of Centrifugal Pump
Authors: Tanaka Takaharu , Liu Chao
Published: August 2008

This paper presents a non-traditional perspective of energy transfer in turbomachinery. Two different kinds of energy are present. One is a kind of invisible imaginary storage energy that stores energy on the acted material and the other is a kind of visible real working energy that does not store the energy on the acted material but acts on the material to move it and do the work in the direction of action. Their acting directions are normal to each other. Their fundamental interrelation and the interrelation with the blade angle of centrifugal pump are theoretically discussed. Experimental test results are also shown in this paper.
On the Validity and Limits of the Gasket Effective Width Concept
Authors: Diany Mohammed , Bouzid Abdel-Hakim , Derenne Michel
Published: August 2008

In the current ASME code procedure for the design of the gasketed bolted joints, the concept of the effective width is introduced to take into account the effect of the non-uniform gasket contact stress distribution. The code fixes a threshold value of the gasket width above which an adjustment of the gasket contact width is introduced. The validity of this threshold has never been verified. Under the normal operating conditions of flanges used with flat gaskets, the definition of this threshold is independent of the bolt load, the average gasket stress, the internal pressure and the flexibility of the joint. In this paper a study on the new limits of the concept of the effective gasket width is conducted. A new approach for the calculation of the effective gasket width, based on the results of an experimental investigation and undertaken in parallel to a numerical study, is presented. This approach takes into account the non-uniform distribution of the gasket stress, the flexibility of the flanges, the mechanical behavior and the sealing performance of the assembly.
Design of a Blast Chamber for Repeated Use
Authors: Seidt Jeremy D. , Trott B. Dale
Published: August 2008

The simplest spherical steel blast containment chamber comprises a spherical shell with a single access port large enough to provide the access required by the application to the interior of the chamber. For small chambers, the access port may approach the radius of the chamber. Such a relatively large port requires a heavy reinforcing ring structure to avoid stress concentrations around the port. The eccentricity caused by the port reinforcement leads to undesirably large localized bending mode stresses following a blast containment event. These stresses can exceed the first-cycle fundamental response to the blast load by a factor greater than two. This paper describes the development of a finite element program to analyze the occurrence of these complex oscillations. This quick-running program provides a means to evaluate design modifications to control unwanted oscillations. This approach leads to the development of safe cost-effective blast containment chamber designs.
Improved Reactor Vessel and Bottom Nozzle UT Inspection Experience
Authors: Glass S. W. , Richmond A. , Alexander G.
Published: August 2008

Framatome ANP, an AREVA and Siemens company, recently completed a combined ten-year reactor pressure vessel (RPV) in-service inspection (ISI) and a volumetric ultrasonic (UT) examination of all bottom-mounted nozzles (BMNs) at Florida Power & Light’s (FPL) Turkey Point-3 nuclear station. Both the 10-year RPV robot and the BMN tool had undergone significant improvements since their last deployment. The enhancements focused primarily on reducing inspection times. The new tools were also designed to minimize the in-containment lay-down area and utility support during the inspection period. This latter aspect was particularly critical for FPL during this outage because of the busy refuel floor schedule that included both vessel examination and head replacement tasks. It was logical to combine these two examinations since they are both performed with the internals completely removed. The vessel examination required approximately 4 days (95.5 hours) and the BMN examination required 1.5 days (36 hours). Total “hook-to-hook” time was 5.75 days (138 hours) — more than 1 day ahead of schedule. The dose savings over alternate inspection approaches for the BMN examination was also very significant. This paper discusses the tool improvements and new techniques used for the examinations of the RPV and the BMNs as well as the field experience during the FPL examination.
Photothermal NDE of CRD Penetration J-Groove Welds
Authors: Glass S. W. , Piriou Marc
Published: August 2008

A programmatic inspection of both old and replacement Reactor Pressure Vessel (RPV) heads is required by US nuclear utilities in response to the observed cracks and in some cases, leaks. Flaws can initiate either in the nozzle pipe, or in the J-Groove weld between the nozzle and the head. Inspection of the J-groove weld surface has historically been performed by eddy current (ET) or die-penetrant (PT) methods (Reference 1). Both approaches require complex robotic delivery mechanisms, are time consuming to perform, and are subject to false positive indications, or missed calls due to the very complex geometry. A new field-deployable photothermal non-destructive examination (NDE) system has been developed that offers distinct advantages over the ET or PT approach. A laser is scanned to heat a short line (∼20mm) on the material surface. Heat propagation perpendicular to the line is tracked with an IR imaging device. By appropriate signal processing, the image can enhance temperature change gradients indicative of cracks or material flaws. The method can be applied from up to 2 meters away from the surface and the detailed surface scans can be an optical scan rather than a complex-motion contacting tool scan of the surface. This paper outlines laboratory performance of the photothermal NDE system, discusses potential advantages over existing technology for RPV head J-groove inspection, and outlines additional developments for full field implementation.
Effect of Corrosion and Inclined Angle on Static Strength of Fillet-Welded Joint of 500 MPa-Class Steel
Authors: Matsushita Hisoa , Nakai Tatsuro , Yamamoto Norio
Published: August 2008

There are reported cases of serious accidents in ship hull structures of aged ships due to corrosion of steel after long period of use. This paper presents basic information on the effect of corrosion on static strength, that is, tensile strength, bending strength and shear strength, of fillet-welded joints of 500MPa-class steel used for ship hull construction. It is based on experimental results using specimens made of material of corroded fillet-welded joints of actual old ships and as-fabricated fillet-welded joint and simulated corroded fillet-welded joint. And also the effect of inclined angles on perpendicular direction shear strength of fillet-welded joint is investigated. Basically, static strength of the fillet-welded joint is affected by the (R) ratio of thickness of steel plates to total thickness of throat of the weld metal. When R was greater than 1.0, fracture occurred at weld metal under tensile stress condition or shear stress condition. However, under bending stress condition fracture at weld metal occurred when R was greater than 1.4. The effect of inclined angles on shear strength of fillet-welded joints is also presented.
Load Reduction on Valve Position Indicators in High Vibration Environments
Authors: Reich Alton J. , Doherty Steve J. , Williams Keith A.
Published: August 2008

The Arnold Engineering Development Center (AEDC) testing complex includes more than 50 wind tunnels, test cells, arc heaters, and other specialized test facilities. Of these, 27 units have capabilities that are unmatched in the United States, and 14 are unmatched in the world. These unique facilities create equally unique operating environments for instrumentation used for monitoring and control of test conditions. Several high flow-rate, supersonic wind tunnels utilize off-the-shelf angular displacement transducers (ADTs) for monitoring the position of 90° valves (i.e. butterfly valves) used to control the air flow-rate and bulk pressure during testing. Due to the high air flow rates in supply and exhaust ducts, there are significant structural vibrations to which the ADTs are subjected. These ADTs have experienced an unacceptably high rate of failure during testing. In the event of an ADT failure, alternative flow paths may, in some cases, be utilized. If an alternative path cannot be found, however, test operations must be suspended while the faulty sensor is replaced; leading to significant cost and schedule impacts associated with the down-time. This paper discusses an effort to understand the root cause of the ADT failures based on design information, and experience in the field. Several alternative mounting conditions were considered in order to reduce the vibrational loads acting on the ADT. A number of the alternatives consisted of utilizing different shaft couplings to couple the motion of the valve stems and the ADT sensor shaft. Experiments were performed at the University of Alabama’s Applied Controls Laboratory to test the effect of the different enclosures and shaft couplings. Preliminary results indicate that the shaft coupling, in particular, have a direct impact on shaft loads transmitted to the ADT. Test results and conclusions are presented.
A Two-Parameter Description of the Behaviour of a Process Zone at a Crack Tip: Relation Between the Parameters
Authors: Smith E.
Published: August 2008

The relative displacement of the crack faces and the tensile stress ahead of a Mode I elastic crack tip can be expressed, in the immediate vicinity of the tip, by two-term power series expansions, the two terms being associated with the stress intensity factor KI and a dimensionless parameter g0. These parameters feature prominently in cohesive process zone models of a crack tip with regard to the crack tip opening displacement vT, process zone size s, the crack opening area A and the effective opening area AD of the process zone. This paper shows that KI and g0 depend upon each other via a relation which is dependent upon the geometrical configuration but is independent of the configuration’s loading pattern.
Fluid Encasement and Flow Within Sub-Structured Blast Panels
Authors: Karr Dale G. , Kasey Christian G. , Kim Sung Ham , Cilenti Michael A. , Pisini Suresh K. , Perlin Marc
Published: August 2008

We address the design and analysis of blast resistant panels consisting of layered substructures with fluid filled chambers. The panels are designed to absorb energy from an air blast by progressive elastic-plastic, through-thickness collapse of the panel substructure. This mechanism of energy absorption is enhanced further by the presence of fluid within alternating chambers of the panel substructure. The fluid primarily contributes to blast effects mitigation by providing increased initial mass to the resisting system, by direct dissipation of energy through viscosity, and by redirecting momentum imparted to the system. Analyses are presented first of the structural system design without fluid. Plastic collapse mechanisms are addressed for optimum design for quasi-static loading. Analytical, numerical and experimental results are discussed. Selected panel geometry is then used to analyze the system with fluid encasement. Simulations of fluid-structure interaction during panel collapse due to adjacent air blasts are presented. The key aspects of optimal design for blast effects mitigation are discussed. The importance of maximizing fluid momentum transfer and redirection, the encasement details including structural passages for prescribed fluid flow, and the system viscosity resulting from fluid-structure dynamics are examined.
Estimation of Master Curve Based RTTo Reference Temperature From CVN Data
Authors: Wallin Kim R. W. , Nagel Gerhard , Keim Elisabeth , Siegele Dieter
Published: August 2008

The ASME code cases N-629 and N-631 permits the use of a Master Curve-based index temperature (RTTo ≡ T0 + 19.4°C) as an alternative to traditional RTNDT-based methods of positioning the ASME KIc, and KIR curves. This approach was adopted to enable use of Master Curve technology without requiring the wholesale changes to the structure of the ASME Code that would be needed to use all aspects of Master Curve technology. For the brittle failure analysis considering irradiation embrittlement additionally a procedure to predict the adjustment of fracture toughness for EOL from irradiation surveillance results must be available as by NRC R.G. 1.99 Rev. 2 e.g.: ART = Initial RTNDT + ΔRTNDT + Margin. The conservatism of this procedure when RTNDT is replaced by RTTo is investigated for western nuclear grade pressure vessel steels and their welds. Based on a systematic evaluation of nearly 100 different irradiated material data sets, a simple relation between RTToirr, RTToref and ΔT41JRG is proposed. The relation makes use of the R.G. 1.99 Rev. 2 and enables the minimizing of margins, necessary for conventional correlations based on temperature shifts. As an example, the method is used to assess the RTTo as a function of fluence for several German pressure vessel steels and corresponding welds. It is shown that the method is robust and well suited for codification.