Performance Benefits (performance + benefit)

Distribution by Scientific Domains


Selected Abstracts


Performance benefits of growth-form plasticity in a clonal red seaweed

BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2009
KEYNE MONRO
Phenotypic plasticity may be adaptive if the phenotype expressed in a focal environment performs better there relative to alternative phenotypes. Plasticity in morphology may particularly benefit modular organisms that must tolerate environmental change with limited mobility, yet this hypothesis has rarely been evaluated for the modular inhabitants of subtidal marine environments. We test the hypothesis for Asparagopsis armata, a clonal red seaweed whose growth-form plasticity across light environments is consistent with the concept of foraging behaviour in clonal plants. We manipulated the light intensity to obtain clonal replicates of compact, densely branched (,phalanx') phenotypes and elongate, sparsely branched (,guerrilla') phenotypes, which we reciprocally transplanted between inductive light environments to explore the performance consequences of a poor phenotype,environment match. Consistent with the hypothesis of adaptive plasticity, we found that performance (as relative growth rate) depended significantly on the interaction between growth form and environment. Each growth form performed better in its inductive environment than the alternative form, implying that this type of plasticity, thought to be adaptive for clonal plants, may also benefit photoautotrophs in marine environments. Given the prevalence and diversity of modular phyla in such systems, they offer a relatively unexplored opportunity to broaden our understanding of the evolutionary ecology of phenotypic plasticity. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 97, 80,89. [source]


From experience: leading dispersed teams

THE JOURNAL OF PRODUCT INNOVATION MANAGEMENT, Issue 4 2002
Preston G. Smith
Although management can gain great performance benefit from colocating cross-functional product development teams, colocation is becoming increasingly difficult to achieve as companies globalize and form alliances. Consequently, this article offers guidance to keep your development team functioning effectively even though it may be dispersed across town or around the world. We aim our suggestions at the team leader, but both team members and managers will find helpful ideas and become sensitive to critical issues. For example, management often underestimates the loss in team performance as the team disperses and incorrectly assumes that communication technologies alone will largely overcome the complications of distance. An effective team depends on open, effective communication, which in turn depends on trust among members. Thus, trust is the foundation, but it is also the very quality that is most difficult to build at a distance. For this reason and for several others that occur in the very front of the project, we suggest that if you can get your team together face-to-face at any time during the project, do it at the beginning. You can establish trust while you are planning the project together, writing the product specification, formulating working approaches, and creating communication protocols (for example, how long before an e-mail must be answered?). Likewise, the most important maintenance activity during the middle of the project is retaining an effective level of trust, which is far easier than having to rebuild trust. In part, you accomplish this by "humanizing" the project: sharing team member biographical information, telling an occasional good-natured joke, and knowing when a colleague's family member is in the hospital. We also cover communication technologies,which ones to select and why you need a variety of media. Although such technologies are necessary for running a dispersed team, they are not nearly as sufficient as many technology suppliers suggest. Another complication is that differences in culture tend to grow as the team spreads over greater distances, encountering different time zones, languages, ethnic groups, and thus corresponding values. Although such differences place challenges before the team, diversity also offers advantages to those who are sensitive to the facets of culture. Consequently, we break culture down into its components and suggest ways of working with each one. Although we tend to underestimate the complications of working at a distance today, in time, teams will learn the skills needed. In the meantime, the perceptive manager and team leader will pay special attention to building these skills. [source]


Babylon: middleware for distributed, parallel, and mobile Java applications

CONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 10 2008
Willem van Heiningen
Abstract Babylon is a collection of tools and services that provide a 100% Java-compatible environment for developing, running and managing parallel, distributed and mobile Java applications. It incorporates features such as object migration, asynchronous method invocation, and remote class loading, while providing an easy-to-use interface. Additionally, Babylon enables Java applications to seamlessly create and interact with remote objects, while protecting those objects from other applications by implementing access restrictions and separate namespaces. The implementation of Babylon centers around dynamic proxies, a feature first available in Java 1.3, that allow proxy objects to be created at runtime. Dynamic proxies play a key role in achieving the goals of Babylon. The potential cluster computing benefits of the system are demonstrated with experimental results, which show that sequential Java applications can achieve significant performance benefits from using Babylon to parallelize their work across a cluster of workstations. Copyright © 2008 John Wiley & Sons, Ltd. [source]


Optimum multiple tuned mass dampers for structures under the ground acceleration based on the uniform distribution of system parameters

EARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 5 2003
Chunxiang Li
Abstract The five MTMD models, with natural frequencies being uniformly distributed around their mean frequency, have been recently presented by the first author. They are shown to have the near-zero optimum average damping ratio (more precisely, for a given mass ratio there is an upper limit on the total number, beyond which the near-zero optimum average damping ratio occurs). In this paper, the eight new MTMD models (i.e. the UM-MTMD1,UM-MTMD3, US-MTMD1,US-MTMD3, UD-MTMD1 and UD-MTMD2), with the system parameters (mass, stiffness and damping coefficient) being, respectively, uniformly distributed around their average values, have been, for the first time here, proposed to seek for the MTMD models without the near-zero optimum average damping ratio. The structure is represented by the mode-generalized system corresponding to the specific vibration mode that needs to be controlled. Through minimization of the minimum values of the maximum dynamic magnification factors (DMF) of the structure with the eight MTMD models (i.e. through the implementation of Min.Min.Max.DMF), the optimum parameters and values of Min.Min.Max.DMF for these eight MTMD models are investigated to evaluate and compare their control performance. The optimum parameters include the optimum mass spacing, stiffness spacing, damping coefficient spacing, frequency spacing, average damping ratio and tuning frequency ratio. The six MTMD models without the near-zero optimum average damping ratio (i.e. the UM-MTMD1,UM-MTMD3, US-MTMD1, US-MTMD2 and UD-MTMD2) are found through extensive numerical analyses. Likewise, the optimum UM-MTMD3 offers the higher effectiveness and robustness and requires the smaller damping with respect to the rest of the MTMD models in reducing the responses of structures subjected to earthquakes. Additionally, it is interesting to note, by comparing the optimum UM-MTMD3 with the optimum MTMD-1 recently investigated by the first author, that the effectiveness and robustness for the optimum UM-MTMD3 is almost identical to that for the optimum MTMD-1 (without inclusion of the optimum MTMD-1 with the near-zero optimum average damping ratio). Recognizing these performance benefits, it is preferable to employ the optimum UM-MTMD3 or the optimum MTMD-1 without the near-zero optimum average damping ratio, when installing the MTMD for the suppression of undesirable oscillations of structures under earthquakes. Copyright © 2003 John Wiley & Sons, Ltd. [source]


A robust approach to the UAV task assignment problem

INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 2 2008
Mehdi Alighanbari
Abstract This paper presents a new robust approach to the task assignment of unmanned aerial vehicles (UAVs) operating in uncertain dynamic environments for which the optimization data, such as target cost and target,UAV distances, are time varying and uncertain. The impact of this uncertainty in the data is mitigated by tightly integrating two approaches for improving the robustness of the assignment algorithm. One approach is to design task assignment plans that are robust to the uncertainty in the data, which reduces the sensitivity to errors in the situational awareness (SA), but can be overly conservative for long duration plans. A second approach is to replan as the SA is updated, which results in the best plan given the current information, but can lead to a churning type of instability if the updates are performed too rapidly. The strategy proposed in this paper combines robust planning with the techniques developed to eliminate churning. This combination results in the robust filter-embedded task assignment algorithm that uses both proactive techniques that hedge against the uncertainty, and reactive approaches that limit churning behavior by the vehicles. Numerous simulations are shown to demonstrate the performance benefits of this new algorithm. Copyright © 2007 John Wiley & Sons, Ltd. [source]


Examining the Conditional Limits of Relational Governance: Specialized Assets, Performance Ambiguity, and Long-Standing Ties

JOURNAL OF MANAGEMENT STUDIES, Issue 7 2008
Laura Poppo
abstract Despite recognition of the benefits of relational governance in inter-organizational exchanges, factors that may erode its value have received little examination. We extend the literature by asking whether self-interested opportunities and long-standing ties erode the positive association between relational governance and performance. Consistent with transaction cost and moral hazard logics, exchange hazards, particularly asset specificity and difficult performance measurement, dampen the positive association of relational governance and performance. We further find, consistent with recent inquiries into the dark side of embedded ties that the performance benefits associated with relational governance decline when parties rely on repeated partnerships. [source]


An Investigation Into the Diversification,Performance Relationship in the U.S. Property,Liability Insurance Industry

JOURNAL OF RISK AND INSURANCE, Issue 3 2008
B. Elango
This article investigates the relationship between product diversification and firm performance in the U.S. property,liability insurance industry using data over the 1994 through 2002 time period. Using various measures of product diversification and firm performance, we find that the extent of product diversification shares a complex and nonlinear relationship with firm performance. Our findings suggest that performance benefits associated with product diversification are contingent upon an insurer's degree of geographic diversification. Robustness tests using subsamples and market returns for public firms show consistent results. [source]


Optimizing performance of benzoate and phthalate blends for vinyl applications

JOURNAL OF VINYL & ADDITIVE TECHNOLOGY, Issue 4 2005
William D. Arendt
To achieve required performance, blends of plasticizers are commonly used in flexible vinyl applications. Typically, when fast fusion is required, high solvating phthalates have been utilized in plasticizer blends. Benzoate esters are high solvators and can also be used in these blends. However, even though benzoate plasticizers offer additional performance benefits that can complement general-purpose phthalate performance, most of the literature does not include the use of benzoate plasticizers in blends with phthalates. The purpose of this article is to demonstrate the performance benefits of blending benzoate and phthalate plasticizers. The approach selected to accomplish this task was to develop performance data by utilizing a mixture design approach with DOE (design of experiments) software. A resilient flooring plastisol formulation was selected as the model. The following properties were obtained: degassing, low and high shear viscosity, viscosity stability of the plastisol, gel and fusion characteristics, tensile strength vs. temperature, vinyl heat stability, stain resistance, volatility, and UV stability. The data indicate how to utilize the advantage of benzoates as "process aids" to speed production rates and improve product quality. J. VINYL. ADDIT. TECHNOL. 11:150,154, 2005. © 2005 Society of Plastics Engineers [source]


Influence of oil type on the performance characteristics of a two-axial groove journal bearing

LUBRICATION SCIENCE, Issue 9 2009
D. M. C. McCarthy
Abstract The use of environmentally adapted lubricants (EALs) is a subject of growing interest to industry as legislation increasingly demands the replacement of mineral oil lubricants. Vegetable-based fluids are widely seen as providing lubricants from a renewable source, as well as meeting demands for improved biodegradability. However, at present, utilization of such fluids is limited due to their rapid oxidation. EALs produced from other base stocks (i.e. synthetic esters) have been shown to provide performance benefits in hydrodynamic thrust bearings. In the present study, a hydrodynamic journal bearing test rig has been employed to compare the performance of three EALs (a VG32 saturated ester, rapeseed base fluid and a propylene glycol dioleate) relative to three mineral turbine oils (ISOVG32, ISOVG46 and ISOVG68) in the hydrodynamic regime. Results are given in terms of temperature, power loss and minimum film thickness. The impact of oil viscosity index is also discussed. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Physiological and performance effects of glycerol hyperhydration and rehydration

NUTRITION REVIEWS, Issue 12 2009
Simon P Van Rosendal
Studies have shown that beverages containing glycerol can enhance and maintain hydration status and may improve endurance exercise performance by attenuating adverse physiological changes associated with dehydration. Improvements to performance include increased endurance time to exhaustion by up to 24%, or a 5% increase in power or work. However, some studies have found no performance benefits during either prolonged exercise or specific skill and agility tests. In studies that have shown benefits, the improvements have been associated with thermoregulatory and cardiovascular changes. These include increased plasma volume and sweat rates, as well as reduced core temperature and ratings of perceived exertion. In a very small number of subjects, glycerol consumption has been associated with side-effects including nausea, gastrointestinal discomfort, dizziness, and headaches. In summary, while glycerol and fluid ingestion results in hyperhydration, the documented benefits to exercise performance remain inconsistent. [source]


Commercializing air traffic control: Have the reforms worked?

CANADIAN PUBLIC ADMINISTRATION/ADMINISTRATION PUBLIQUE DU CANADA, Issue 1 2008
Glen McDougall
Many countries have restructured their ANSPs by granting managerial and financial autonomy and creating new mechanisms for regulation and accountability to major consumers of air navigation services. These reforms have exemplified principles often associated with the New Public Management. The United States is the major exception to this international trend. Commercialization has allowed significant improvements in service quality without substantial increases in cost of service or erosion of safety standards. Other public interest considerations have also been protected. These performance benefits can be attributed to key decisions on the governance of new air navigation service organizations. Sommaire: Les fournisseurs de services de navigation aérienne jouent un rôle crucial dans le fonctionnement d'une économie moderne. De nombreux pays ont restructuré leurs fournisseurs de services en leur accordant une autonomie financière et de gestion, et en créant de nouveaux mécanismes de réglementation et d'imputabilité envers les principaux consommateurs de services de navigation aérienne. Ces réformes ont illustré les principes souvent associés à la Nouvelle gestion publique. Les États-Unis sont la principale exception à cette tendance internationale. La commercialisation a permis d'apporter d'importantes améliorations à la qualité des services sans entraîner pour autant d'augmentations substantielles des coûts de services, ou une érosion des normes de sécurité. D'autres considérations d'intérêt public ont également été protégées. Ces avantages en termes de performance peuvent être attribués à des décisions clés en matière de gouvernance des nouveaux organismes de services de navigation aérienne. [source]