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Design Criterion (design + criterion)
Selected AbstractsThe concept of work compatibility: An integrated design criterion for improving workplace human performance in manufacturing systemsHUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES, Issue 4 2004S. Abdallah In this paper, we present the concept of work compatibility as an integrated work design criterion that simultaneously improves human health and safety, productivity, and work quality in manufacturing systems. In this respect, we have modeled work compatibility as a work design parameter that mathematically integrates the energizing (i.e., system resources) and the demand (i.e., system requirements) forces in the work system. A mathematical equation has been derived for the work compatibility matrix. Furthermore, an operating zone has been developed in which there is a region of optimality for the employee to function on practical grounds with a good degree of efficiency and sustainability. An application example is provided to demonstrate the potential of work compatibility to improve productivity and quality along with improvement in worker safety and health. © 2004 Wiley Periodicals, Inc. Hum Factors Man 14: 379,402, 2004. [source] An energy-efficient multipath routing protocol for wireless sensor networksINTERNATIONAL JOURNAL OF COMMUNICATION SYSTEMS, Issue 7 2007Ye Ming Lu Abstract The energy consumption is a key design criterion for the routing protocols in wireless sensor networks. Some of the conventional single path routing schemes may not be optimal to maximize the network lifetime and connectivity. In this paper, we propose a distributed, scalable and localized multipath search protocol to discover multiple node-disjoint paths between the sink and source nodes. We also propose a load balancing algorithm to distribute the traffic over the multiple paths discovered. We compare our proposed scheme with the directed diffusion, directed transmission, N -to-1 multipath routing, and the energy-aware routing protocols. Simulation results show that our proposed scheme has a higher node energy efficiency, lower average delay and control overhead than those protocols. Copyright © 2006 John Wiley & Sons, Ltd. [source] Range error detection caused by occlusion in non-coaxial LADARs for scene interpretationJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 10 2005Bingbing Liu When processing laser detection and ranging (LADAR) sensor data for scene interpretation, for example, for the purposes of feature extraction and/or data association in mobile robotics, most previous work models such devices as processing range data which follows a normal distribution. In this paper, it is demonstrated that commonly used LADARs suffer from incorrect range readings at changes in surface reflectivity and/or range discontinuities, which can have a much more detrimental effect on such algorithms than random noise. Most LADARs fall into two categories: coaxial and separated transmitter and receiver configurations. The latter offer the advantage that optical crosstalk is eliminated, since it can be guaranteed that all of the transmitted light leaves the LADAR and is not in any way partially reflected within it due to the beam-splitting techniques necessary in coaxial LADARs. However, they can introduce a significant disparity effect, as the reflected laser energy from the target can be partially occluded from the receiver. As well as demonstrating that false range values can result due to this occlusion effect from scanned LADARs, the main contribution of this paper is that the occurrence of these values can be reliably predicted by monitoring the received signal strength and a quantity we refer to as the "transceiver separation angle" of the rotating mirror. This paper will demonstrate that a correct understanding of such systematic errors is essential for the correct further processing of the data. A useful design criterion for the optical separation of the receiver and transmitter is also derived for noncoaxial LADARs, based on the minimum detectable signal amplitude of a LADAR and environmental edge constraints. By investigating the effects of various sensor and environmental parameters on occlusion, some advice is given on how to make use of noncoaxial LADARs correctly so as to avoid range errors when scanning environmental discontinuities. © 2005 Wiley Periodicals, Inc. [source] Modeling an active conformation for linear peptides and design of a competitive inhibitor for HMG-CoA reductaseJOURNAL OF MOLECULAR RECOGNITION, Issue 4 2008Valeriy V. Pak Abstract This study presents an approach that can be used to search for lead peptide candidates, including unconstrained structures in a recognized sequence. This approach was performed using the design of a competitive inhibitor for 3-hydroxy-3-methylglutaryl CoA reductase (HMGR). In a previous design for constrained peptides, a head-to-tail cyclic structure of peptide was used as a model of linear analog in searches for lead peptides with a structure close to an active conformation. Analysis of the conformational space occupied by the peptides suggests that an analogical approach can be applied for finding a lead peptide with an unconstrained structure in a recognized sequence via modeling a cycle using fixed residues of the peptide backbone. Using the space obtained by an analysis of the bioactive conformations of statins, eight cyclic peptides were selected for a peptide library based on the YVAE sequence as a recognized motif. For each cycle, the four models were assessed according to the design criterion ("V" parameter) applied for constrained peptides. Three cyclic peptides (FGYVAE, FPYVAE, and FFYVAE) were selected as lead cycles from the library. The linear FGYVAE peptide (IC50,=,0.4,µM) showed a 1200-fold increase the inhibitory activity compared to the first isolated LPYP peptide (IC50,=,484,µM) from soybean. Experimental analysis of the modeled peptide structures confirms the appropriateness of the proposed approach for the modeling of active conformations of peptides. Copyright © 2008 John Wiley & Sons, Ltd. [source] Design of follow-up experiments for improving model discrimination and parameter estimationNAVAL RESEARCH LOGISTICS: AN INTERNATIONAL JOURNAL, Issue 8 2004Szu Hui Ng Abstract One goal of experimentation is to identify which design parameters most significantly influence the mean performance of a system. Another goal is to obtain good parameter estimates for a response model that quantifies how the mean performance depends on influential parameters. Most experimental design techniques focus on one goal at a time. This paper proposes a new entropy-based design criterion for follow-up experiments that jointly identifies the important parameters and reduces the variance of parameter estimates. We simplify computations for the normal linear model by identifying an approximation that leads to a closed form solution. The criterion is applied to an example from the experimental design literature, to a known model and to a critical care facility simulation experiment. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004 [source] Blocking Two-level Factorial ExperimentsQUALITY AND RELIABILITY ENGINEERING INTERNATIONAL, Issue 3 2007Murat Kulahci Abstract Blocking is commonly used in experimental design to eliminate unwanted variation by creating more homogeneous conditions for experimental treatments within each block. While it has been a standard practice in experimental design, blocking fractional factorials still presents many challenges due to differences between treatment and blocking variables. Lately, new design criteria such as the total number of clear effects and fractional resolution have been proposed to design blocked two-level fractional factorial experiments. This article presents a flexible matrix representation for two-level fractional factorials that will allow experimenters and software developers to block such experiments based on any design criterion that is suitable with the experimental conditions. Copyright © 2006 John Wiley & Sons, Ltd. [source] Soil vapor extraction system design: A case study comparing vacuum and pore-gas velocity cutoff criteriaREMEDIATION, Issue 1 2006Kenneth L. Dixon Soil vapor extraction (SVE) systems are typically designed based on the results of a vadose-zone pumping test (transient or steady-state) using a pressure criterion to establish the zone of influence (ZOI). A common problem associated with pressure-based SVE design is overestimating the ZOI of the extraction well. As a result, design strategies based upon critical pore- gas velocity (CPGV) have become more common. Field tests were conducted at the Savannah River Site (SRS) to determine the influence of a vapor extraction well based upon both a pressure and pore- gas velocity design criterion. The results from these tests show that an SVE system designed based upon a CPGV is more robust and will have shorter cleanup times due to increased flow throughout the treatment zone. Pressure-based SVE design may be appropriate in applications where soil gas containment is the primary objective; however, in cases where the capture and removal of contaminated soil gas is the primary objective, CPGV is a better design criterion. © 2006 Wiley Periodicals, Inc. [source] Design of cellular porous biomaterials for wall shear stress criterionBIOTECHNOLOGY & BIOENGINEERING, Issue 4 2010Yuhang Chen Abstract The microfluidic environment provided by implanted prostheses has a decisive influence on the viability, proliferation and differentiation of cells. In bone tissue engineering, for instance, experiments have confirmed that a certain level of wall shear stress (WSS) is more advantageous to osteoblastic differentiation. This paper proposes a level-set-based topology optimization method to regulate fluidic WSS distribution for design of cellular biomaterials. The topological boundary of fluid phase is represented by a level-set model embedded in a higher-dimensional scalar function. WSS is determined by the computational fluid dynamics analysis in the scale of cellular base cells. To achieve a uniform WSS distribution at the solid,fluid interface, the difference between local and target WSS is taken as the design criterion, which determines the speed of the boundary evolution in the level-set model. The examples demonstrate the effectiveness of the presented method and exhibit a considerable potential in the design optimization and fabrication of new prosthetic cellular materials for bioengineering applications. Biotechnol. Bioeng. 2010;107:737,746. © 2010 Wiley Periodicals, Inc. [source] | ||||||||||