bluuebunny/crossref_metadata_2025 huggingface dataset:
Determinants of outward foreign direct investment from BRIC countries: an explorative study
Authors: Holtbrügge Dirk , Kreppel Heidi
Published: January 2012

Purpose

Outward foreign direct investment (FDI) of firms from Brazil, Russia, India and China has increased significantly during the last few years. Despite this trend, comprehensive research on the specific determinants and antecedents of outward FDI from BRIC countries is still underrepresented. The purpose of this paper is to give a more comprehensive understanding of outward FDI from BRIC countries.

Design/methodology/approach

Based on an exploratory approach, case studies of eight companies were conducted. Both a within‐case and a cross‐case approach were conducted.

Findings

The findings reveal the relevance of determinants on the country, industry and firm level. Gaining access to new markets is of utmost importance for all firms. Additionally, most companies seek to obtain access to technological resources and management know‐how, therefore emphasizing the availability of these resources in the target countries. While the internationalization of Brazilian and Indian companies is primarily driven by economic motives, many Chinese and Russian firms also receive substantial political support from their governments to invest abroad, especially in strategically important industries. On the firm‐level, the strength of firm‐specific resources is highlighted. BRIC country firms possess specific strengths that help them to enter both developing as well as developed countries and to pursue their internationalization strategy.

Originality/value

The aim of this study is to systematically analyze the determinants of FDI of firms from BRIC countries. While previous studies in this context are based on internationalization theories which were at least implicitly focused on FDI of firms from developed markets, the authors use a more emic approach and look for specific determinants of outward FDI of firms originating in BRIC countries.
Success predictor for international joint ventures in Vietnam
Authors: Minh Tri Cao
Published: January 2012

Purpose

The purpose of this paper is to determine a success predictor for Vietnam‐based international joint ventures (IJVs).

Design/methodology/approach

Using the multiple case study method, seven successful IJVs in Ho Chi Minh City – Vietnam's largest and most economically dynamic metropolitan area – were examined by reviewing their business records and by personal interviews with senior management and staff. Two specific types of data collection procedures were applied: methodological triangulation (using multiple methods of data capture: in‐depth interviews, non‐participation observation during visits, and analysis both of companies' internal and external documents) and data triangulation (using a variety of data sources: spreading out during a 30‐month period and involved 75 in‐depth face to face interviews).

Findings

Successful IJVs in Vietnam usually use four popular control mechanisms. Action‐control, result‐control, and personnel‐control mechanisms co‐exist in a closely‐knit environment yet still influence each other in a process assisted by relationship control mechanism. As a condition for success, an IJV should have at least one control mechanism at a high level of importance with no control mechanisms positioned at a low level of importance.

Originality/value

Those who are building successful IJVs in Vietnam should first determine proper control mechanisms necessary for IJV success. It also proves useful and helpful if investors and local government use these results to jointly develop successful IJVs for the benefit of Vietnam's economy and society.
Getting real about innovations
Authors: Fox Stephen
Published: January 2012

Purpose

The purpose of this paper is to provide an overview of how descriptions of innovations can be formulated in order to reduce the potential for ontological uncertainty. Ontological uncertainty exists when individuals have perceptions about the future consequences of an innovation, which are based more on their diverse world views than on the innovation itself.

Design/methodology/approach

The research comprised unstructured interviews and review of the literature relating to innovation hype, innovation reliability, innovation negative unintended consequences, and critical realism.

Findings

Critical realist diagrams provide the basis for descriptions that can encompass an innovation's purpose; the functions and conditions which are necessary for its reliable operation; and also potential negative unintended consequences that might arise from the innovation.

Practical implications

There can be much hype and little clarity surrounding an innovation. This can make it easier for different stakeholders to have different perceptions of the same innovation. By increasing the clarity of descriptions, there can be less uncertainty about the purpose, reliability, and consequences of an innovation.

Originality/value

The originality of the paper is that provides example innovation descriptions which illustrate how hype can be decreased and clarity can be increased. The value of this paper is that supports reduction of ontological uncertainty in practice.
Project management maturity: a critical analysis of existing and emergent factors
Authors: Pasian Beverly , Sankaran Shankar , Boydell Spike
Published: January 2012

Purpose

The purpose of this paper is to report on the findings of a doctoral thesis examining the limitations of project management maturity and associated models. It examines the management of undefined projects where the definition, repeatability and predictability of processes cannot be reasonably expected. The challenge to project management maturity theorists is to recognize the possibility of project management maturity in an environment characterized by undefined project elements and the requirement for greater flexibility in their management.

Design/methodology/approach

This inquiry was supported by a multimethod (MXM) research design with two stages: a content/textual analysis of two different collections of maturity models, and an exploratory case study of two university sites. The analysis (supported by grounded theory techniques) contributed to the development of a 4‐node conceptual framework that was used as the primary data collection instrument at two Canadian university sites.

Findings

Results indicate that multiple non‐process factors can contribute to a mature project management capability. These can include context‐specific values, specialized bodies of knowledge (instructional design), customer involvement, third‐party influence, and tacit “human factors” such as trust and creativity. The demands of this inquiry also demonstrated the need for a new data collection sequence in multimethod research design theory.

Practical implications

Practitioners are encouraged to consider customer involvement, organizational dynamics and adaptable variables such as leadership (among other non‐process factors) in their assessment of the maturity of their project management capability, and designers of future models could explore a multi‐dimensional approach that includes context‐specific factors to assessing and defining project management maturity.

Originality/value

This research expands the conceptual view and practical assessment of project management maturity; offers new analysis of the current generation of project management maturity models; documents e‐Learning project management; and defines a new data collection sequencing model.
Fracture resistance of root filled premolar teeth restored with direct composite resin with or without cusp coverage
Authors: Xie K. X. , Wang X. Y. , Gao X. J. , Yuan C. Y. , Li J. X. , Chu C. H.
Published: January 2012

Xie KX, Wang XY, Gao XJ, Yuan CY, Li JX, Chu CH. Fracture resistance of root filled premolar teeth restored with direct composite resin with or without cusp coverage. International Endodontic Journal, 45, 524–529, 2012.

Aim  To evaluate the fracture resistance and fracture patterns of root filled maxillary first premolar teeth (with mesio–occlusal cavity preparation) restored with several composite restoration designs.

Methodology  One hundred extracted sound human maxillary first premolars were randomly divided into five groups. Group 1 remained untreated (negative control). Conventional root canal treatment with additional mesial–occlusal cavity preparation was carried out on teeth in groups 2–5. In group 2, the teeth were restored intra‐coronally with direct composite resin (positive control). In group 3, the palatal cusps of the teeth were reduced, and the cavities were restored with composite resin covering the palatal cusp (partial coverage). In group 4, the buccal and palatal cusps along with the distal marginal ridges were reduced; the cavities and cusps were restored with composite resin (conventional full coverage). In group 5, the buccal and palatal cusps were reduced but the distal marginal ridges were conserved. The cavities and the cusps were restored with composite resin (modified full coverage). All teeth were subjected to a progressive compressive loading parallel to their longitudinal axis until fracture. Fracture resistance was analysed using the one‐way ANOVA and Fisher’s LSD test. Fracture patterns were analyzed with chi‐square test. The significance level was set at 0.05.

Results  The fracture resistance (mean ± SD) of groups 1–5 was 1131 ± 207N, 904 ± 184N, 927 ± 224N, 1095 ± 289N and 1085 ± 243N, respectively (groups 1, 4, 5 > groups 2, 3; P = 0.004). Cusp fractures were recorded as the fracture pattern in 20 (100%), 19 (95%), 16 (80%), 8 (40%) and 12 (60%) premolars in groups 1–5, respectively (groups 1, 2 > groups 4, 5; group 3 > group 4; P < 0.001).

Conclusions  When direct composite resin was used to restore root filled maxillary first premolar teeth involving a proximal surface, those restored with full‐coverage designs had greater fracture resistance.
1,4‐Bis[2‐(3,5‐dichloropyridyloxy)]benzene induces substantial hyperplasia in fibrotic mouse liver
Authors: Bugyik Edina , Dezső Katalin , Turányi Eszter , Szurián Kinga , Paku Sándor , Nagy Peter
Published: January 2012

The proliferative response of hepatocytes in vivo can be induced by two mechanisms: severe damage to hepatic tissue results in regenerative growth and so‐called primary hepatocyte mitogens can initiate liver cell proliferation without preceding loss of parenchyma. The regulation of the two responses is quite different. The decreased regenerative response of cirrhotic/fibrotic liver is well known, and is a severe obstacle to surgery of the diseased liver. In the present experiments we investigated the efficiency of a primary hepatocyte mitogen 1,4‐Bis[2‐(3,5‐dichloropyridyloxy)]benzene (TCPOBOB) on two different liver cirrhosis/fibrosis models in mice induced by chronic administration of CCl4 and thioacetamide respectively. BrdU incorporation and cyclin A expression established clearly that there is a reduced but still powerful mitogenic response of the fibrotic livers. Therefore, primary hepatocyte mitogens appear to be suitable to be used to rescue the regenerative response of cirrhotic livers.
Examining nursing vital signs documentation workflow: barriers and opportunities in general internal medicine units
Authors: Yeung Melanie S , Lapinsky Stephen E , Granton John T , Doran Diane M , Cafazzo Joseph A
Published: January 2012

Aims.  To characterise the nursing practices of vital signs collection and documentation in a general internal medicine environment to inform strategies for improving workflow design.

Background.  Clinical workflow analysis is critical to identify barriers and opportunities in current processes. Analysis can guide the design and development of novel technological solutions to produce greater efficiencies and effectiveness in healthcare delivery. Research surrounding vital signs documentation workflow in general internal medicine environments has received very little attention making it difficult to compare the effectiveness of new technologies.

Design.  Qualitative ethnographic analyses and quantitative time–motion study were conducted.

Methods.  Workflows of 24 nurses at three hospitals in five general internal medicine environments were captured, and timeliness of vital signs assessment and documentation was measured.

Results.  Clinical assessment of vital signs was consistent, but the documentation process was highly variable within groups and between hospitals. Two themes characterised workflow barriers surrounding point‐of‐care documentation. First, a lack of standardised documentation methods for vital signs resulted in higher rates of transcription, increasing not only the likelihood of errors but delays in recording and accessibility of information. Second, despite advancements in electronic documentation systems, the observed system was not conducive to point‐of‐care documentation. Average electronic documentation was significantly longer than paper documentation. Nurses developed ad hoc workarounds that were inefficient and undermined the intent of electronic documentation.

Conclusion.  We have identified barriers and opportunities to improve the efficiency of nursing vital signs documentation. Changes in technology, workflows and environmental design allow for significant improvements and deserve further exploration.

Relevance to clinical practice.  Attention to clinical practice and environments can improve the workflow of prompt vital signs documentation and increase clinical productivity and timeliness of information for clinical decisions, as well as minimising transcription errors leading to safer patient care.
Accuracy in documentation of peripheral venous catheters in paediatric care: an intervention study in electronic patient records
Authors: Förberg Ulrika , Johansson Eva , Ygge Britt‐Marie , Wallin Lars , Ehrenberg Anna
Published: January 2012

Aims.  The aim of this study is to compare the accuracy and completeness in the recording of peripheral venous catheters before and after implementing a template in the electronic patient record in paediatric care.

Background.  As a basis for quality improvement and research purposes and to ensure patient safety, accurate clinical data need to be easily accessible in patient records. Several studies have concluded that the relation between performed care and what is documented in patient records is poor.

Design.  Before and after study.

Method.  The study took place at a large paediatric university hospital in Sweden. Inclusion criteria were patients who were admitted to one of the included wards, had one or several peripheral venous catheters and were available at the ward at the time for data collection. Data were collected by observations and record audits before and then four and 10 months after the introduction of a template for recording peripheral venous catheters in a structured and standardised way.

Results.  A significant increase in peripheral venous catheters with complete recording was observed after as compared with before the intervention. The percentage of peripheral venous catheters with recording of any kind was relatively stable (85–93%). The overall recording of peripheral venous catheters insertion did not improve, but there was an increase in the recording of side and size after the intervention. One of the 22 complications observed before the intervention was documented and none of the complications (n = 17 and n = 9) after.

Conclusion.  The electronic patient record did not provide accurate data on peripheral venous catheters in paediatric care neither before nor after the intervention.

Relevance to clinical practice.  Further efforts to increase the documentation of catheter‐related complications are needed. Integrated decision support systems in electronic patient records that remind nurses to inspect peripheral venous catheters regularly could be one solution.
Comparing Delay Minimization and Emissions Minimization in the Network Design Problem
Authors: Ferguson Erin M. , Duthie Jennifer , Travis Waller S.
Published: January 2012

Abstract:  Traditionally, transportation road networks are designed for minimal congestion. Unfortunately, such approaches do not guarantee minimal vehicle emissions. To fill this apparent gap in network design research, an emissions network design problem and solution method is proposed in this article for the purposes of comparing to the traditional network design results. Three air pollutants are considered on two road networks. The model is formulated as a bi‐level optimization problem and a solution is approximated using a genetic algorithm. The influence of demand uncertainty is also incorporated into the model. Designing for minimal congestion tends to increase emissions of criteria air pollutants. However, not adding capacity to a road network also increases emissions of pollutants. Therefore, an optimization problem and solution method, such as the emissions network design problem and solution method presented here, is useful for identifying capacity additions that reduce vehicle emissions. It is also useful for understanding the tradeoffs between designing a network for minimal congestion versus minimal vehicle emissions.
Validated UV‐spectrophotometric method for the evaluation of the efficacy of makeup remover
Authors: Charoennit P. , Lourith N.
Published: January 2012

Synopsis

A UV‐spectrophotometric method for the analysis of makeup remover was developed and validated according to ICH guidelines. Three makeup removers for which the main ingredients consisted of vegetable oil (A), mineral oil and silicone (B) and mineral oil and water (C) were sampled in this study. Ethanol was the optimal solvent because it did not interfere with the maximum absorbance of the liquid foundation at 250 nm. The linearity was determined over a range of makeup concentrations from 0.540 to 1.412 mg mL−1 (R2 = 0.9977). The accuracy of this method was determined by analysing low, intermediate and high concentrations of the liquid foundation and gave 78.59–91.57% recoveries with a relative standard deviation of <2% (0.56–1.45%). This result demonstrates the validity and reliability of this method. The reproducibilities were 97.32 ± 1.79, 88.34 ± 2.69 and 95.63 ± 2.94 for preparations A, B and C respectively, which are within the acceptable limits set forth by the ASEAN analytical validation guidelines, which ensure the precision of the method under the same operating conditions over a short time interval and the inter‐assay precision within the laboratory. The proposed method is therefore a simple, rapid, accurate, precise and inexpensive technique for the routine analysis of makeup remover efficacy.
Erysipelas‐like erythema as the presenting feature of familial Mediterranean fever
Authors: Lidar M. , Doron A. , Barzilai A. , Feld O. , Zaks N. , Livneh A. , Langevitz P.
Published: January 2012

Background  ‘Erysipelas‐like’ erythema (ELE) is a well recognized, although uncommon, manifestation of familial Mediterranean fever (FMF), which is frequently mistaken for infectious erysipelas, especially when forming the initial disease presentation.

Aim  To clinically and genetically characterize ELE as the first manifestation of FMF.

Methods  FMF patients with ELE as the first disease presentation (study group), were compared with FMF patients with ELE, appearing during the disease course (control group I), and to those FMF patients who never had ELE (control group II).

Results  Patients of the study group were comparable to patients without ELE with respect to all demographic, clinical and genetic features studied, and yet differed from patients with ELE appearing later in the disease course in disease severity score (1.7 ± 0.4 vs. 2.4 ± 0.6, P = 0.01), length of diagnosis delay (7.2 ± 6.4 vs. 2.3 ± 3.3 years, P=0.037), age of FMF onset (24.8 ± 19.9 vs. 5.6 ± 5.7 years of age, P=0.014) and rate of homozygosity to the M694V mutation (14.3% vs. 68.7% respectively). ELE traits in the study and control groups were alike.

Conclusions  FMF with ELE as the first disease manifestation form an uncommon subgroup, clinically and genetically diverging from the rest of the FMF‐ELE patients.
The use of the twin model to investigate the genetics and epigenetics of skin diseases with genomic, transcriptomic and methylation data
Authors: Bataille V. , Lens M. , Spector T.D.
Published: January 2012

Twins have always fascinated medical research even before the discovery of DNA and the understanding of the differences between identical and non‐identical twins. Dermatology with the benefit of being able to visualize phenotypes was one of the first specialities reporting on the fascinating concordance in identical (MZ) twins in the 1920’s. Over the last 20 years, the heritability of skin diseases using twins has been clearly demonstrated, across a wide variety of traits including melanoma, polymorphic light eruption, psoriasis, eczema and acne. Other rarer diseases have also been shown to have a significant genetic basis such as lupus, sarcoidosis and lichen sclerosus. Following evidence of heritability for many skin disease the next step was Genome‐Wide Association Studies (GWAS) which are uncovering new genes in large twin cohorts. The twin model is also ideal for the new field of epigenetics, investigating subtle differences in DNA methylation within discordant MZ pairs for a disease, as well as differences in CNVs. Twins are also valuable for examining differences in gene function via RNA expression in twins discordant for a skin trait or disease.
Anticancer activity of bovine α‐lactalbumin treated with microbial transglutaminase
Authors: JEONG JI‐EUN , HONG YOUN‐HO
Published: January 2012

This study investigated the effects of bovine α‐lactalbumin (α‐La) treated with microbial transglutaminase on human cancer cells, cell cultures and growth rate assays. The anticancer activity for 10 mg/mL of bovine α‐lactalbumin (α‐La) was measured as ∼90% in a human colorectal cancer cell line HCT 116. For the human bone cancer cell line SJSA‐1, α‐La hydrolysis resulted in higher cytotoxicity compared to untreated tumour cells. The formation of polymers of α‐La was suppressed by the addition of ethylenediaminetetraacetic acid, indicating that polymers of α‐La are promoted by metal ions such as Ca2+. The effect of α‐La on the morphology of SJSA‐1 cells was manifested as morphological changes compatible with apoptosis. Bovine milk α‐La with and without microbial transglutaminase is considered a valuable food ingredient and a nutraceutical for human health.
Evidence that angiotensin‐(1–7) is an intermediate of gonadotrophin‐induced oocyte maturation in the rat preovulatory follicle
Authors: Honorato‐Sampaio Kinulpe , Pereira Virginia M. , Santos Robson A. S. , Reis Adelina M.
Published: January 2012

Several studies have shown the presence of components of the renin–angiotensin system in mammalian ovaries and their involvement in ovarian physiology. We have previously shown the presence of angiotensin‐(1–7) [Ang‐(1–7)], an important biologically active component of the renin–angiotensin system, and its receptor, Mas, in rat, rabbit and human ovaries. We have also shown the involvement of Ang‐(1–7) in the rabbit ovulatory process in vitro. In the present study, we observed that Ang‐(1–7) stimulated the resumption of meiosis in oocytes of rat preovulatory follicles, reaching more than 30% of oocytes with germinal vesicle breakdown. The specific antagonist of the Mas receptor, A‐779, inhibited the germinal vesicle breakdown induced by Ang‐(1–7) and reduced the oocyte maturation stimulated by luteinizing hormone (LH). Immunohistochemistry showed that LH increased both Ang‐(1–7) and angiotensin‐converting enzyme 2 (ACE2) staining in preovulatory follicles. The effect of gonadotrophins on mRNA expression of Mas and ACE2 in ovaries of immature equine chorionic gonadotrophin‐primed rats was analysed by real‐time PCR after 6 h of human chorionic gonadotrophin (hCG) injection, which exhibits LH‐like effects. After hCG treatment, ACE2 mRNA expression was higher in the ovaries of treated rats than in the ovaries of control rats, whereas Mas mRNA levels were unchanged. A‐779 changed the steroidogenesis stimulated by LH. An increased testosterone concentration and decreased progesterone levels were measured in the follicle medium. In conclusion, our results suggest that LH upregulates the ACE2–Ang‐(1–7)–Mas axis and that Ang‐(1–7) promotes meiotic resumption, possibly as a gonadotrophin intermediate.
Passive and Switched Stiffness Vibration Controllers Using Fluidic Flexible Matrix Composites
Authors: Lotfi-Gaskarimahalle Amir , Scarborough Lloyd H. , Rahn Christopher D. , Smith Edward C.
Published: January 2012

This paper investigates passive and semi-active vibration control using fluidic flexible matrix composites (F2MC). F2MC tubes filled with fluid and connected to an accumulator through a fixed orifice can provide damping forces in response to axial strain. If the orifice is actively controlled, the stiffness of F2MC tubes can be dynamically switched from soft to stiff by opening and closing an on/off valve. Fiber reinforcement of the F2MC tube kinematically relates the internal volume to axial strain. With an open valve, the fluid in the tube is free to move in or out of the tube, so the stiffness is low. With a closed valve, however, the high bulk modulus fluid resists volume change and produces high axial stiffness. The equations of motion of an F2MC-mass system are derived using a 3D elasticity model and the energy method. The stability of the unforced dynamic system is proven using a Lyapunov approach. A reduced-order model for operation with either a fully open or fully closed valve motivates the development of a zero vibration (ZV) controller that suppresses vibration in finite time. Coupling of a fluid-filled F2MC tube to a pressurized accumulator through a fixed orifice is shown to provide significant passive damping. The open-valve orifice size is optimized for optimal passive, skyhook, and ZV controllers by minimizing the integral time absolute error cost function. Simulation results show that the optimal open valve orifice provides a damping ratio of 0.35 compared with no damping in closed-valve case. The optimal ZV controller outperforms optimal passive and skyhook controllers by 32.9% and 34.2% for impulse and 34.7% and 60% for step response, respectively. Theoretical results are confirmed by experiments that demonstrate the improved damping provided by optimal passive control F2MC and fast transient response provided by semi-active ZV control.
Model Development of Quantum Dot Devices for γ Radiation Detection Using Block Diagram Programming
Authors: Mahmoud Imbaby I. , El_Tokhy Mohamed S. , Konber Hussein A.
Published: January 2012

The main objective of this paper is to develop a model of quantum dot (QD) devices for incident γ radiation detection. A novel methodology is introduced to characterize the effect of γ radiation on QD detectors. In this methodology, we used VisSim environment along with the block diagram programming procedures. The benefit of using this modeling language is the simplicity of carrying out the performance’s measurement through computer simulation instead of setting up a practical procedure, which is expensive as well as difficult in management. The roles that the parameters of fabrication can play in the characteristics of QDs devices are discussed through developed models implemented by VisSim environment. The rate equations of the QD devices under γ radiation are studied. The effect of incident γ radiation on the optical gain, power, and output photon densities is investigated. The implemented models can help designers and scientists to optimize their devices to meet their requirements.
A Comparison of the Effects of Nonlinear Damping on the Free Vibration of a Single-Degree-of-Freedom System
Authors: Tang Bin , Brennan M. J.
Published: January 2012

This article concerns the free vibration of a single-degree-of-freedom (SDOF) system with three types of nonlinear damping. One system considered is where the spring and the damper are connected to the mass so that they are orthogonal, and the vibration is in the direction of the spring. It is shown that, provided the displacement is small, this system behaves in a similar way to the conventional SDOF system with cubic damping, in which the spring and the damper are connected so they act in the same direction. For completeness, these systems are compared with a conventional SDOF system with quadratic damping. By transforming all the equations of motion of the systems so that the damping force is proportional to the product of a displacement dependent term and velocity, then all the systems can be directly compared. It is seen that the system with cubic damping is worse than that with quadratic damping for the attenuation of free vibration.
Specified Motion of Piezoelectrically Actuated Structures
Authors: Seigler T. M. , Ghasemi A. H.
Published: January 2012

The problem considered is that of solving for the control input that generates partly specified motion of a deformable structure with distributed piezoelectric actuation. The motion constraint, called the program constraint, is specified as a desired relation on the motion of selected material points of the structure. The solution is based on a projection method applicable to a class of finite-dimensional dynamical systems which includes many common vibration models. For a nonlinear model with a nonlinear program constraint, the procedure in general results in a set of differential algebraic equations. It is shown that for linear models with linear periodic program constraints, the system is reduced to a set of algebraic equations. Application examples are presented for a Euler-Bernoulli beam to demonstrate the usefulness of the procedure.
Extreme-Value-Based Statistical Bounding of Low, Mid, and High Frequency Responses of a Forced Plate With Random Boundary Conditions
Authors: Seçgin A. , Dunne J. F. , Zoghaib L.
Published: January 2012

The problem of statistically bounding the response of an engineering structure with random boundary conditions is addressed across the entire frequency range: from the low, through the mid, to the high frequency region. Extreme-value-based bounding of both the FRF and the energy density response is examined for a rectangular linear plate with harmonic point forcing. The proposed extreme-value (EV) approach, previously tested only in the low frequency region for uncoupled and acoustically-coupled uncertain structures, is examined here in the mid and high frequency regions in addition to testing at low frequencies. EV-based bounding uses an asymptotic threshold exceedance model of Type-I, to extrapolate the m-observational return period to an arbitrarily-large batch of structures. It does this by repeatedly calibrating the threshold model at discrete frequencies using a small sample of response data generated by Monte Carlo simulation or measurement. Here the discrete singular convolution (DSC) method – a transfrequency computation approach for deterministic vibration - is used to generate Monte Carlo samples. The accuracy of the DSC method is first verified (i) in terms of the spatial distribution of total energy density and (ii) across the frequency range, by comparison with a mode superposition method and Statistical Energy Analysis (SEA). EV-based bound extrapolations of the receptance FRF and total energy density are then compared with: (i) directly-estimated bounds using a full set of Monte Carlo simulations and (ii) with total mean energy levels obtained with SEA. This paper shows that for a rectangular plate structure with random boundary conditions, EV-based statistical bounding of both the FRF and total energy density response is generally applicable across the entire frequency range.
Two Algorithms for Mass Normalizing Mode Shapes From Impact Excited Continuous-Scan Laser Doppler Vibrometry
Authors: Yang Shifei , Sracic Michael W. , Allen Matthew S.
Published: January 2012

Continuous-scan laser Doppler vibrometry (CSLDV), a concept where a vibrometer measures the motion of a structure as the laser measurement point sweeps over the structure, has proven to be an effective method for rapidly obtaining mode shape measurements with very high spatial detail using a completely non-contact approach. Existing CSLDV methods obtain only the operating shapes or arbitrarily scaled modes of a structure, but the mass-normalized modes are sought in many applications; for example, when the experimental modal model is to be used for substructuring predictions or to predict the effect of structural modifications. This paper extends an approach based on impact excitation and CSLDV, presenting a new least squares algorithm that can be used to estimate the mass-normalized modes of a structure from CSLDV measurements. Two formulations are derived: one based on real-modes that is appropriate when the structure is proportionally damped and a second that accommodates a complex-mode description. The latter approach also gives the algorithm further latitude to accommodate time-synchronization errors in the data acquisition system. The method is demonstrated on a free-free beam, where both CSLDV and a conventional test using an accelerometer and a roving-hammer are used to find its first seven mass normalized modes. The scale factors produced by both methods are found to agree with a tuned analytical model for the beam to within about ten percent. The results are further verified by attaching a small mass to the beam and using the model to predict the change in the structure’s natural frequencies and mode shapes due to the added mass.
Inverse Problems in Heat Transfer: New Trends on Solution Methodologies and Applications
Authors: Orlande Helcio R. B.
Published: January 2012

Systematic methods for the solution of inverse problems have developed significantly during the past two decades and have become a powerful tool for analysis and design in engineering. Inverse analysis is nowadays a common practice in which teams involved with experiments and numerical simulation synergistically collaborate throughout the research work, in order to obtain the maximum of information regarding the physical problem under study. In this paper, we briefly review various approaches for the solution of inverse problems, including those based on classical regularization techniques and those based on the Bayesian statistics. Applications of inverse problems are then presented for cases of practical interest, such as the characterization of nonhomogeneous materials and the prediction of the temperature field in oil pipelines.
Reduced Order Thermal Models of Multiscale Microsystems
Authors: Joshi Yogendra
Published: January 2012

Thermal systems often involve multiple spatial and temporal scales, where transport information from one scale is relevant at others. Optimized thermal design of such systems and their control require approaches for their rapid simulation. These activities are of increasing significance due to the need for energy efficiency in the operation of these systems. Traditional full-field simulation methodologies are typically unable to resolve these scales in a computationally efficient manner. We summarize recent work on simulations of conjugate transport processes over multiple length scales via reduced order modeling through approaches such as compact finite elements and proper orthogonal decomposition. In order to incorporate the influence of length scales beyond those explicitly considered, lumped models are invoked, with appropriate handshaking between the two frameworks. We illustrate the methodology through selected examples, with a focus on information technology systems.
Control of Turbulent Transport: Less Friction and More Heat Transfer
Authors: Kasagi Nobuhide , Hasegawa Yosuke , Fukagata Koji , Iwamoto Kaoru
Published: January 2012

Because of the importance of fundamental knowledge on turbulent heat transfer for further decreasing entropy production and improving efficiency in various thermofluid systems, we revisit a classical issue whether enhancing heat transfer is possible with skin friction reduced or at least not increased as much as heat transfer. The answer that numerous previous studies suggest is quite pessimistic because the analogy concept of momentum and heat transport holds well in a wide range of flows. Nevertheless, the recent progress in analyzing turbulence mechanics and designing turbulence control offers a chance to develop a scheme for dissimilar momentum and heat transport. By reexamining the governing equations and boundary conditions for convective heat transfer, the basic strategies for achieving dissimilar control in turbulent flow are generally classified into two groups, i.e., one for the averaged quantities and the other for the fluctuating turbulent components. As a result, two different approaches are discussed presently. First, under three typical heating conditions, the contribution of turbulent transport to wall friction and heat transfer is mathematically formulated, and it is shown that the difference in how the local turbulent transport of momentum and that of heat contribute to the friction and heat transfer coefficients is a key to answer whether the dissimilar control is feasible. Such control is likely to be achieved when the weight distributions for the stress and flux in the derived relationships are different. Second, we introduce a more general methodology, i.e., the optimal control theory. The Fréchet differentials obtained clearly show that the responses of velocity and scalar fields to a given control input are quite different due to the fact that the velocity is a divergence-free vector, while the temperature is a conservative scalar. By exploiting this inherent difference, the dissimilar control can be achieved even in flows where the averaged momentum and heat transport equations have the same form.
Macroscopic and Microscale Phenomena in Multiphase Energy Storage and Transport Systems
Authors: Kawaji Masahiro
Published: January 2012

Complex macroscale and microscale heat and mass transfer phenomena are encountered in thermal energy storage and transport systems. Those systems involving ice slurries and nanoemulsions of phase change materials can be used for either cooling or heating applications or both, which can contribute to the reduced usage of electricity during peak hours. But heat and mass transfer and stability issues are encountered in the production, transport and storage of the heat storage media. In this paper, both the heat transfer enhancement effect and detrimental effects such as Ostwald ripening and supercooling are discussed along with the flow properties.
Characterization of Melting and Solidification Phenomena in Electromagnetic Punching of Aluminum Tubes
Authors: Waele Wim De , Koen Faes , Haver Wim Van
Published: January 2012

Electromagnetic punching of tubular products is considered to be a promising innovative perforating process. The required punching energy decreases when using high velocities. Also, less tools are required when compared to conventional mechanical punching. However, the increase in punching speed can involve new strain and fracture mechanisms which are characteristic of the dynamic loading. In high energy rate forming processes the effect of temperature versus time gradient on the material properties becomes important due to the heat accumulated from plastic deformation and friction. The deformation induced heating will promote strain localization in it, possibly degrade its formability and cause premature failure in the regions of high localized strain. The feasibility of the electromagnetic pulse forming process for punching holes in aluminum cylindrical specimens has been investigated on an experimental trial-and-error basis. Experiments were performed using a Pulsar system (model 50/25) with a maximum charging energy of 50 kJ and a discharge circuit frequency of 14 kHz. Microscopic and metallographic inspection of the punched workpieces, together with hardness measurements, was performed to critically evaluate the quality of the cuts. It was observed that damage occurred at part of the edge of the punched hole during some of the perforation experiments. It was evidenced that in most workpieces, especially those performed at higher charging energy levels, a considerably high temperature must have been reached in the regions near the punched hole. The aluminum in this region was assumed to have melted and resolidified. These assumptions were affirmed by the following observations. Microscopic-size precipitates present in the unaffected base metal microstructure, had completely dissolved in that region; shrinkage cavities and dendrite rich regions were clearly visible. Next to this region, a heat affected zone was present where the grain boundaries had partially melted and precipitates partially disappeared. Considerably high temperatures, in the order of 520 to 660 °C, were reached in the regions around the punched holes, leading to melting and resolidification of the material. The total width of the thermally affected regions appeared to be larger at higher energy levels. The combination of heat generated by ohmic heating and by plastic deformation in a very short time interval is the most probable cause of the high peak temperatures that have occurred during the electromagnetic punching process.
Probabilistic Fatigue Assessment of a Notched Detail Taking Into Account Mean Stress Effects
Authors: De Jesus Abílio M. P. , Luisa Ruiz Ripoll M. , Fernández-Canteli Alfonso , Castillo Enrique , Pereira Hélder F. S. G.
Published: January 2012

Probabilistic fatigue models are required to account conveniently for the several sources of uncertainty arising in the prediction procedures, such as the scatter in material behavior. In this paper, a recently proposed stress-based probabilistic model is assessed using fatigue data available for the P355NL1 steel (a pressure vessel steel). The referred probabilistic model is a log-Gumbel regression model, able to predict the probabilistic Wöhler field (P–S–N field), taking into account the mean stress (or stress R-ratio) effects. The parameters of the probabilistic model are identified using stress-life data derived for the P355NL1 steel, from smooth specimens, for three distinct stress R-ratios, namely R = −1, R = −0.5, and R = 0. The model requires a minimum of two test series with distinct stress R-ratios. Since data from three test series is available, extrapolations are performed to test the adequacy of the model to make extrapolations for stress R-ratios other than those used in the model parameters assessment. Finally, the probabilistic model is used to model the fatigue behavior of a notched plate made of P355NL1 steel. In particular, the P–S–N field of the plate is modeled and compared with available experimental data. Cyclic elastoplastic analysis of the plate is performed since plasticity at the notch root is developed. The probabilistic model correlated appropriately the stress-life data available for the P355NL1 steel and was able to perform extrapolations for stress ratios other than those used in the model identification. The P–S–N field identified using data from smooth specimens led to consistent predictions of the P–S–N field for a notched plate, demonstrating the adequacy of the probabilistic model also to predict the probabilistic Wöhler field for notched components.
Influence of Chemical Compositions on Lower Ferrite-Austenite Transformation Temperatures in 9% Cr Steels
Authors: Santella Michael L.
Published: January 2012

Computational thermodynamics approach was used to predict the ranges of the lower ferrite-austenite transformation temperatures, A1’s, in three 9% Cr steels. The predicted A1 ranges were: 766–856 °C for SA387 Grade 91, 775–863 °C for SA213 Grade T92, and 676–862 °C for the weld metal SFA-5.23 B9 (2004). For Grade 91 and Grade T92 using the highest tempering temperature permitted by ASME Code, 800 °C, would permit certain alloys conforming to the chemical composition specification to be tempered above their A1, thereby risking the formation of untempered martensite. Similar circumstances exist for weld metal conforming to the SFA-5.23 B9 specification. Linear regression analyses were performed to develop simplified expressions capable of representing the thermodynamically predicted relationships between chemical compositions and A1’s. These are, Grade 91/SFA-5.23 B9 (2004): 805 °C + 2.5(%Cr) + 18.1(%Mo) + 19.1(%Si)+ 37.1(%V) + 19.2(%Nb) − 63.7(%C) − 130.6(%N) − 60.5(%Mn) − 72.3(%Ni) Grade T92:778°C + 4.9(%Cr) + 22.6(%Mo) + 10.8(%W) + 22.9(%Si) + 43.6(%V) + 20.2(%Nb) − 80.6(%C) − 150.7(%N) − 55.1(%Mn) − 68.0(%Ni).
Effects of low-pass filtering on intelligibility of periodically interrupted speech
Authors: Bhargava Pranesh , Başkent Deniz
Published: January 2012

The combined effect of low-pass filtering (cut-off frequencies between 500 and 3000 Hz) and periodic interruptions (1.5 and 10 Hz) on speech intelligibility was investigated. When combined, intelligibility was lower than each manipulation alone, even in some conditions where there was no effect from a single manipulation (such as the fast interruption rate of 10 Hz). By using young normal-hearing listeners, potential suprathreshold deficits and aging effects that may occur due to hearing impairment were eliminated. Thus, the results imply that reduced audibility of high-frequency speech components may partially explain the reduced intelligibility of interrupted speech in hearing impaired persons.
Perceptually based head-related transfer function database optimization
Authors: Katz Brian F. G. , Parseihian Gaëtan
Published: January 2012

In the context of binaural audio rendering, choosing the best head-related transfer function (HRTF) for an individual from large databases poses several problems. This study proposes a method to reduce the size of a given HRTF database. Participants, 45 in total, were asked to rate the quality of binaural synthesis for 46 HRTFs. The lack of reciprocity in the ratings was noted. Results were used to create a perceptually optimized HRTF subset which satisfied all participants’ judgments. The subset was validated using localization tests on a separate group of subjects with results showing reduced errors when subjects were given their best choice, rather than their worst choice HRTF.
Optimization of orthotropic distributed-mode loudspeaker using attached masses and multi-exciters
Authors: Lu Guochao , Shen Yong , Liu Ziyun
Published: January 2012

Based on the orthotropic model of the plate, the method to optimize the sound response of the distributed-mode loudspeaker (DML) using the attached masses and the multi-exciters has been investigated. The attached masses method will rebuild the modes distribution of the plate, based on which multi-exciter method will smooth the sound response. The results indicate that the method can be used to optimize the sound response of the DML.
Evidence of cue use and performance differences in deciphering dysarthric speech
Authors: Choe Yu-kyong , Liss Julie M. , Azuma Tamiko , Mathy Pamela
Published: January 2012

There is substantial performance variability among listeners who transcribe degraded speech. Error patterns from 88 listeners who transcribed dysarthric speech were examined to identify differential use of syllabic strength cues for lexical segmentation. Transcripts from listeners were divided into four groups (ranging from Better- to Poorer- performing). Phrases classified as Higher- and Lower-intelligibility were analyzed separately for each performance group to assess the independent variable of severity. Results revealed that all four listener groups used syllabic strength cues for lexical segmentation of Higher-intelligibility speech, but only the Poorer listeners persisted with this strategy for the Lower-intelligibility phrases. This finding and additional analyses suggest testable hypotheses to address the role of cue-use and performance patterns.