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1

Microcosm assays and Taguchi experimental design for treatment of oil sludge containing high concentration of hydrocarbons.  

PubMed

Microcosm assays and Taguchi experimental design was used to assess the biodegradation of an oil sludge produced by a gas processing unit. The study showed that the biodegradation of the sludge sample is feasible despite the high level of pollutants and complexity involved in the sludge. The physicochemical and microbiological characterization of the sludge revealed a high concentration of hydrocarbons (334,766+/-7001 mg kg(-1) dry matter, d.m.) containing a variety of compounds between 6 and 73 carbon atoms in their structure, whereas the concentration of Fe was 60,000 mg kg(-1) d.m. and 26,800 mg kg(-1) d.m. of sulfide. A Taguchi L(9) experimental design comprising 4 variables and 3 levels moisture, nitrogen source, surfactant concentration and oxidant agent was performed, proving that moisture and nitrogen source are the major variables that affect CO(2) production and total petroleum hydrocarbons (TPH) degradation. The best experimental treatment yielded a TPH removal of 56,092 mg kg(-1) d.m. The treatment was carried out under the following conditions: 70% moisture, no oxidant agent, 0.5% of surfactant and NH(4)Cl as nitrogen source. PMID:19635663

Castorena-Cortés, G; Roldán-Carrillo, T; Zapata-Peñasco, I; Reyes-Avila, J; Quej-Aké, L; Marín-Cruz, J; Olguín-Lora, P

2009-12-01

2

Application of the Taguchi Experimental Design to the Removal of Toxic Metals From Waste Waters by Precipitation as Magnetic Ferrites  

Microsoft Academic Search

Waste waters polluted with toxic metals can be successfully purified by precipitation of the metals from an alkalinised solution containing iron(II) as ferrite sludge with magnetic properties. The magnetic ferrites obtained by this treatment can be disposed or reutilised with smaller risk for the environment since metals contained in the ferrite are less available. A Taguchi experimental design has been

E. Barrado; M. Vega; R. Pardo; M. Ruipérez; J. Medina

1996-01-01

3

Parametric Appraisal of Process Parameters for Adhesion of Plasma Sprayed Nanostructured YSZ Coatings Using Taguchi Experimental Design  

PubMed Central

This paper presents the application of the Taguchi experimental design in developing nanostructured yittria stabilized zirconia (YSZ) coatings by plasma spraying process. This paper depicts dependence of adhesion strength of as-sprayed nanostructured YSZ coatings on various process parameters, and effect of those process parameters on performance output has been studied using Taguchi's L16 orthogonal array design. Particle velocities prior to impacting the substrate, stand-off-distance, and particle temperature are found to be the most significant parameter affecting the bond strength. To achieve retention of nanostructure, molten state of nanoagglomerates (temperature and velocity) has been monitored using particle diagnostics tool. Maximum adhesion strength of 40.56?MPa has been experimentally found out by selecting optimum levels of selected factors. The enhanced bond strength of nano-YSZ coating may be attributed to higher interfacial toughness due to cracks being interrupted by adherent nanozones. PMID:24288490

Mantry, Sisir; Mishra, Barada K.; Chakraborty, Madhusudan

2013-01-01

4

Neutralization of red mud with pickling waste liquor using Taguchi's design of experimental methodology.  

PubMed

'Red mud' or 'bauxite residue', a waste generated from alumina refinery is highly alkaline in nature with a pH of 10.5-12.5. Red mud poses serious environmental problems such as alkali seepage in ground water and alkaline dust generation. One of the options to make red mud less hazardous and environmentally benign is its neutralization with acid or an acidic waste. Hence, in the present study, neutralization of alkaline red mud was carried out using a highly acidic waste (pickling waste liquor). Pickling waste liquor is a mixture of strong acids used for descaling or cleaning the surfaces in steel making industry. The aim of the study was to look into the feasibility of neutralization process of the two wastes using Taguchi's design of experimental methodology. This would make both the wastes less hazardous and safe for disposal. The effect of slurry solids, volume of pickling liquor, stirring time and temperature on the neutralization process were investigated. The analysis of variance (ANOVA) shows that the volume of the pickling liquor is the most significant parameter followed by quantity of red mud with 69.18% and 18.48% contribution each respectively. Under the optimized parameters, pH value of 7 can be achieved by mixing the two wastes. About 25-30% of the total soda from the red mud is being neutralized and alkalinity is getting reduced by 80-85%. Mineralogy and morphology of the neutralized red mud have also been studied. The data presented will be useful in view of environmental concern of red mud disposal. PMID:22751850

Rai, Suchita; Wasewar, Kailas L; Lataye, Dilip H; Mishra, Rajshekhar S; Puttewar, Suresh P; Chaddha, Mukesh J; Mahindiran, P; Mukhopadhyay, Jyoti

2012-09-01

5

Bioslurry phase remediation of chlorpyrifos contaminated soil: process evaluation and optimization by Taguchi design of experimental (DOE) methodology.  

PubMed

Design of experimental (DOE) methodology using Taguchi orthogonal array (OA) was applied to evaluate the influence of eight biotic and abiotic factors (substrate-loading rate, slurry phase pH, slurry phase dissolved oxygen (DO), soil water ratio, temperature, soil microflora load, application of bioaugmentation and humic substance concentration) on the soil bound chlorpyrifos bioremediation in bioslurry phase reactor. The selected eight factors were considered at three levels (18 experiments) in the experimental design. Substrate-loading rate showed significant influence on the bioremediation process among the selected factors. Derived optimum operating conditions obtained by the methodology showed enhanced chlorpyrifos degradation from 1479.99 to 2458.33microg/g (over all 39.82% enhancement). The proposed method facilitated systematic mathematical approach to understand the complex bioremediation process and the optimization of near optimum design parameters, only with a few well-defined experimental sets. PMID:17640730

Venkata Mohan, S; Sirisha, K; Sreenivasa Rao, R; Sarma, P N

2007-10-01

6

Assessing the applicability of the Taguchi design method to an interrill erosion study  

NASA Astrophysics Data System (ADS)

Full-factorial experimental designs have been used in soil erosion studies, but are time, cost and labor intensive, and sometimes they are impossible to conduct due to the increasing number of factors and their levels to consider. The Taguchi design is a simple, economical and efficient statistical tool that only uses a portion of the total possible factorial combinations to obtain the results of a study. Soil erosion studies that use the Taguchi design are scarce and no comparisons with full-factorial designs have been made. In this paper, a series of simulated rainfall experiments using a full-factorial design of five slope lengths (0.4, 0.8, 1.2, 1.6, and 2 m), five slope gradients (18%, 27%, 36%, 48%, and 58%), and five rainfall intensities (48, 62.4, 102, 149, and 170 mm h-1) were conducted. Validation of the applicability of a Taguchi design to interrill erosion experiments was achieved by extracting data from the full dataset according to a theoretical Taguchi design. The statistical parameters for the mean quasi-steady state erosion and runoff rates of each test, the optimum conditions for producing maximum erosion and runoff, and the main effect and percentage contribution of each factor obtained from the full-factorial and Taguchi designs were compared. Both designs generated almost identical results. Using the experimental data from the Taguchi design, it was possible to accurately predict the erosion and runoff rates under the conditions that had been excluded from the Taguchi design. All of the results obtained from analyzing the experimental data for both designs indicated that the Taguchi design could be applied to interrill erosion studies and could replace full-factorial designs. This would save time, labor and costs by generally reducing the number of tests to be conducted. Further work should test the applicability of the Taguchi design to a wider range of conditions.

Zhang, F. B.; Wang, Z. L.; Yang, M. Y.

2015-02-01

7

Application of Taguchi L32 orthogonal array design to optimize copper biosorption by using Spaghnum moss.  

PubMed

In this work, Taguchi L32 experimental design was applied to optimize biosorption of Cu(2+) ions by an easily available biosorbent, Spaghnum moss. With this aim, batch biosorption tests were performed to achieve targeted experimental design with five factors (concentration, pH, biosorbent dosage, temperature and agitation time) at two different levels. Optimal experimental conditions were determined by calculated signal-to-noise ratios. "Higher is better" approach was followed to calculate signal-to-noise ratios as it was aimed to obtain high metal removal efficiencies. The impact ratios of factors were determined by the model. Within the study, Cu(2+) biosorption efficiencies were also predicted by using Taguchi method. Results of the model showed that experimental and predicted values were close to each other demonstrating the success of Taguchi approach. Furthermore, thermodynamic, isotherm and kinetic studies were performed to explain the biosorption mechanism. Calculated thermodynamic parameters were in good accordance with the results of Taguchi model. PMID:25011119

Ozdemir, Utkan; Ozbay, Bilge; Ozbay, Ismail; Veli, Sevil

2014-09-01

8

Determining optimal operation parameters for reducing PCDD/F emissions (I-TEQ values) from the iron ore sintering process by using the Taguchi experimental design.  

PubMed

This study is the first one using the Taguchi experimental design to identify the optimal operating condition for reducing polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/ Fs) formations during the iron ore sintering process. Four operating parameters, including the water content (Wc; range = 6.0-7.0 wt %), suction pressure (Ps; range = 1000-1400 mmH2O), bed height (Hb; range = 500-600 mm), and type of hearth layer (including sinter, hematite, and limonite), were selected for conducting experiments in a pilot scale sinter pot to simulate various sintering operating conditions of a real-scale sinter plant We found that the resultant optimal combination (Wc = 6.5 wt%, Hb = 500 mm, Ps = 1000 mmH2O, and hearth layer = hematite) could decrease the emission factor of total PCDD/Fs (total EF(PCDD/Fs)) up to 62.8% by reference to the current operating condition of the real-scale sinter plant (Wc = 6.5 wt %, Hb = 550 mm, Ps = 1200 mmH2O, and hearth layer = sinter). Through the ANOVA analysis, we found that Wc was the most significant parameter in determining total EF(PCDD/Fs (accounting for 74.7% of the total contribution of the four selected parameters). The resultant optimal combination could also enhance slightly in both sinter productivity and sinter strength (30.3 t/m2/day and 72.4%, respectively) by reference to those obtained from the reference operating condition (29.9 t/m (2)/day and 72.2%, respectively). The above results further ensure the applicability of the obtained optimal combination for the real-scale sinter production without interfering its sinter productivity and sinter strength. PMID:18754384

Chen, Yu-Cheng; Tsai, Perng-Jy; Mou, Jin-Luh

2008-07-15

9

A taguchi method for safety design of artificial marble products  

Microsoft Academic Search

Artificial marble products usually include sinks and kitchen equipments. Frequent accidents of consumer injuries caused by fallen sinks have been reported. This study aims to enhance the safety of marble sink by taking into the consideration of not increasing the cost of production and materials, and by applying the parameter design of Taguchi Method in selecting six controllable factors: defoaming

Wen-Pai Wang; Chung-Shang Chang; Yu-Hsiu Lee

2009-01-01

10

Use of Taguchi method to develop a robust design for the magnesium alloy die casting process  

Microsoft Academic Search

This study applies the Taguchi method to optimize the process parameters for the die casting of thin-walled magnesium alloy parts in computer, communications, and consumer electronics (3C) industries. The objectives of the Taguchi method for robust parameter design are to establish the optimal combination of design parameters and to reduce the variation in quality from a minimum number of experiments.

Der Ho Wu; Mao Sheng Chang

2004-01-01

11

Ex situ slurry phase bioremediation of chrysene contaminated soil with the function of metabolic function: process evaluation by data enveloping analysis (DEA) and Taguchi design of experimental methodology (DOE).  

PubMed

Bioremediation of chrysene in soil matrix was evaluated in soil slurry phase bioreactor in conjugation with metabolic functions (aerobic, anoxic and anaerobic), microenvironment (single and mixed) conditions and nature of mixed consortia (native/resident mixed microflora and bioaugmented inoculum). Twelve experiments were operated independently in agitated-batch reactor keeping all other operating conditions constant (substrate loading rate--0.084 g chrysene/kg soil-day; soil loading rate--10 kg soil/m(3)-day (3:25 soil water ratio); operating temperature--35+/-2 degrees C). Data envelopment analysis (DEA) procedure was employed to analyze the performance of experimental variations in terms of chrysene degradation and pH. The efficacy of anoxic metabolism over the corresponding aerobic and anaerobic metabolic functions was documented. Aerobic metabolic function showed effective degradation capability under mixed microenvironment after augmentation with anaerobic inoculum. Anaerobic metabolic function showed lowest degradation potential. Application of bioaugmentation showed positive influence on the chrysene degradation rate. Design of experimental methodology (DOE) by Taguchi approach was applied to evaluate the effect of four selected factors (native soil microflora, microenvironment, metabolic function and bioaugmentation) on the chrysene degradation process. The optimized factors derived from analysis depicted the requirement of native soil microflora under anoxic metabolic function using mixed microenvironment after augmenting with anaerobic inoculum for achieving effective chrysene degradation efficacy. PMID:18657417

Venkata Mohan, S; Purushotham Reddy, B; Sarma, P N

2009-01-01

12

Formulation development and evaluation of hybrid nanocarrier for cancer therapy: Taguchi orthogonal array based design.  

PubMed

Taguchi orthogonal array design is a statistical approach that helps to overcome limitations associated with time consuming full factorial experimental design. In this study, the Taguchi orthogonal array design was applied to establish the optimum conditions for bovine serum albumin (BSA) nanocarrier (ANC) preparation. Taguchi method with L9 type of robust orthogonal array design was adopted to optimize the experimental conditions. Three key dependent factors namely, BSA concentration (% w/v), volume of BSA solution to total ethanol ratio (v?:?v), and concentration of diluted ethanolic aqueous solution (% v/v), were studied at three levels 3%, 4%, and 5% w/v; 1?:?0.75, 1?:?0.90, and 1?:?1.05?v/v; 40%, 70%, and 100% v/v, respectively. The ethanolic aqueous solution was used to impart less harsh condition for desolvation and attain controlled nanoparticle formation. The interaction plot studies inferred the ethanolic aqueous solution concentration to be the most influential parameter that affects the particle size of nanoformulation. This method (BSA, 4% w/v; volume of BSA solution to total ethanol ratio, 1?:?0.90?v/v; concentration of diluted ethanolic solution, 70% v/v) was able to successfully develop Gemcitabine (G) loaded modified albumin nanocarrier (M-ANC-G) of size 25.07 ± 2.81?nm (? = -23.03 ± 1.015?mV) as against to 78.01 ± 4.99?nm (? = -24.88 ± 1.37?mV) using conventional method albumin nanocarrier (C-ANC-G). Hybrid nanocarriers were generated by chitosan layering (solvent gelation technique) of respective ANC to form C-HNC-G and M-HNC-G of sizes 125.29 ± 5.62?nm (? = 12.01 ± 0.51?mV) and 46.28 ± 2.21?nm (? = 15.05 ± 0.39?mV), respectively. Zeta potential, entrapment, in vitro release, and pH-based stability studies were investigated and influence of formulation parameters are discussed. Cell-line-based cytotoxicity assay (A549 and H460 cells) and cell internalization assay (H460 cell line) were performed to assess the influence on the bioperformance of these nanoformulations. PMID:24106715

Tekade, Rakesh K; Chougule, Mahavir B

2013-01-01

13

Taguchi statistical design and analysis of cleaning methods for spacecraft materials  

NASA Technical Reports Server (NTRS)

In this study, we have extensively tested various cleaning protocols. The variant parameters included the type and concentration of solvent, type of wipe, pretreatment conditions, and various rinsing systems. Taguchi statistical method was used to design and evaluate various cleaning conditions on ten common spacecraft materials.

Lin, Y.; Chung, S.; Kazarians, G. A.; Blosiu, J. O.; Beaudet, R. A.; Quigley, M. S.; Kern, R. G.

2003-01-01

14

Taguchi Approach to Design Optimization for Quality and Cost: An Overview  

NASA Technical Reports Server (NTRS)

Calibrations to existing cost of doing business in space indicate that to establish human presence on the Moon and Mars with the Space Exploration Initiative (SEI) will require resources, felt by many, to be more than the national budget can afford. In order for SEI to succeed, we must actually design and build space systems at lower cost this time, even with tremendous increases in quality and performance requirements, such as extremely high reliability. This implies that both government and industry must change the way they do business. Therefore, new philosophy and technology must be employed to design and produce reliable, high quality space systems at low cost. In recognizing the need to reduce cost and improve quality and productivity, Department of Defense (DoD) and National Aeronautics and Space Administration (NASA) have initiated Total Quality Management (TQM). TQM is a revolutionary management strategy in quality assurance and cost reduction. TQM requires complete management commitment, employee involvement, and use of statistical tools. The quality engineering methods of Dr. Taguchi, employing design of experiments (DOE), is one of the most important statistical tools of TQM for designing high quality systems at reduced cost. Taguchi methods provide an efficient and systematic way to optimize designs for performance, quality, and cost. Taguchi methods have been used successfully in Japan and the United States in designing reliable, high quality products at low cost in such areas as automobiles and consumer electronics. However, these methods are just beginning to see application in the aerospace industry. The purpose of this paper is to present an overview of the Taguchi methods for improving quality and reducing cost, describe the current state of applications and its role in identifying cost sensitive design parameters.

Unal, Resit; Dean, Edwin B.

1990-01-01

15

Economic design of bar X & S control charts based on Taguchi's loss function and its optimization  

NASA Astrophysics Data System (ADS)

Much research effort has been devoted to economic design of bar X & S control charts, however, there are some problems in usual methods. On the one hand, it is difficult to estimate the relationship between costs and other model parameters, so the economic design method is often not effective in producing charts that can quickly detect small shifts before substantial losses occur; on the other hand, in many cases, only one type of process shift or only one pair of process shifts are taken into consideration, which may not correctly reflect the actual process conditions. To improve the behavior of economic design of control chart, a cost & loss model with Taguchi's loss function for the economic design of bar X & S control charts is embellished, which is regarded as an optimization problem with multiple statistical constraints. The optimization design is also carried out based on a number of combinations of process shifts collected from the field operation of the conventional control charts, thus more hidden information about the shift combinations is mined and employed to the optimization design of control charts. At the same time, an improved particle swarm optimization (IPSO) is developed to solve such an optimization problem in design of bar X & S control charts, IPSO is first tested for several benchmark problems from the literature and evaluated with standard performance metrics. Experimental results show that the proposed algorithm has significant advantages on obtaining the optimal design parameters of the charts. The proposed method can substantially reduce the total cost (or loss) of the control charts, and it will be a promising tool for economic design of control charts.

Guo, Yu; Yang, Wen'an; Liao, Wenhe; Gao, Shiwen

2012-05-01

16

Multidisciplinary design of a rocket-based combined cycle SSTO launch vehicle using Taguchi methods  

NASA Technical Reports Server (NTRS)

Results are presented from the optimization process of a winged-cone configuration SSTO launch vehicle that employs a rocket-based ejector/ramjet/scramjet/rocket operational mode variable-cycle engine. The Taguchi multidisciplinary parametric-design method was used to evaluate the effects of simultaneously changing a total of eight design variables, rather than changing them one at a time as in conventional tradeoff studies. A combination of design variables was in this way identified which yields very attractive vehicle dry and gross weights.

Olds, John R.; Walberg, Gerald D.

1993-01-01

17

Application of Taguchi Design and Response Surface Methodology for Improving Conversion of Isoeugenol into Vanillin by Resting Cells of Psychrobacter sp. CSW4  

PubMed Central

For all industrial processes, modelling, optimisation and control are the keys to enhance productivity and ensure product quality. In the current study, the optimization of process parameters for improving the conversion of isoeugenol to vanillin by Psychrobacter sp. CSW4 was investigated by means of Taguchi approach and Box-Behnken statistical design under resting cell conditions. Taguchi design was employed for screening the significant variables in the bioconversion medium. Sequentially, Box-Behnken design experiments under Response Surface Methodology (RSM) was used for further optimization. Four factors (isoeugenol, NaCl, biomass and tween 80 initial concentrations), which have significant effects on vanillin yield, were selected from ten variables by Taguchi experimental design. With the regression coefficient analysis in the Box-Behnken design, a relationship between vanillin production and four significant variables was obtained, and the optimum levels of the four variables were as follows: initial isoeugenol concentration 6.5 g/L, initial tween 80 concentration 0.89 g/L, initial NaCl concentration 113.2 g/L and initial biomass concentration 6.27 g/L. Under these optimized conditions, the maximum predicted concentration of vanillin was 2.25 g/L. These optimized values of the factors were validated in a triplicate shaking flask study and an average of 2.19 g/L for vanillin, which corresponded to a molar yield 36.3%, after a 24 h bioconversion was obtained. The present work is the first one reporting the application of Taguchi design and Response surface methodology for optimizing bioconversion of isoeugenol into vanillin under resting cell conditions. PMID:24250648

Ashengroph, Morahem; Nahvi, Iraj; Amini, Jahanshir

2013-01-01

18

Applying Taguchi Methods To Brazing Of Rocket-Nozzle Tubes  

NASA Technical Reports Server (NTRS)

Report describes experimental study in which Taguchi Methods applied with view toward improving brazing of coolant tubes in nozzle of main engine of space shuttle. Dr. Taguchi's parameter design technique used to define proposed modifications of brazing process reducing manufacturing time and cost by reducing number of furnace brazing cycles and number of tube-gap inspections needed to achieve desired small gaps between tubes.

Gilbert, Jeffrey L.; Bellows, William J.; Deily, David C.; Brennan, Alex; Somerville, John G.

1995-01-01

19

OPTIMIZATION USING TAGUCHI METHOD FOR ELECTROMAGNETIC APPLICATIONS  

E-print Network

OPTIMIZATION USING TAGUCHI METHOD FOR ELECTROMAGNETIC APPLICATIONS Wei-Chung Weng, Fan Yang, Veysel electromagnetic optimization technique based on Taguchi method. Using the concept of the orthogonal array (OA. This study uses a new electromagnetic optimization technique, Taguchi method [1], to design a linear antenna

Elsherbeni, Atef Z.

20

Experimental Design  

NSDL National Science Digital Library

This site, created by Michelle Lacey of Yale University, gives an explanation, a definition of and an example using experimental design. Topics include: experimentation, control, randomization, randomized design, block randomization and replication. Overall, this site provides a good overview of these topics.

Lacey, Michelle

2009-01-05

21

Taguchi design for optimization and development of antibacterial drug-loaded PLGA nanoparticles.  

PubMed

This research report was to develop Cefixime loaded polylactide-co-glycolide (PLGA) nanoparticles using modified precipitation method. TEM analysis indicated formation of well-formed, smooth, spherical nanoparticles with no aggregates whereas XRD recommended dispersion of drug in PLGA carrier system in amorphous form. The polymer and stabilizer concentration and organic to aqueous ratio were found to be significant factors for nanoparticles and their optimization using Taguchi design (L9). The design formulations showed entrapment efficiency (EE), particle size and poly-dispersity index (PDI) ranging 68.31 ± 1.74%, 159.8-157.7 nm and 0.126-0.149, respectively indicated small and stable nanoparticles with good homogeneity and encapsulation. The design optimized formulation drug release and permeation studies demonstrated that it is four times sustained release behavior and 1.74 times better permeation than free drug. The result of microbiological assay also suggested that optimized formulation has significant antibacterial activity against intracellular multidrug resistance (MDR) of Salmonella typhi. PMID:24315945

Sonam; Chaudhary, Hema; Kumar, Vikash

2014-03-01

22

Microencapsulation of (deoxythymidine)20-DOTAP complexes in stealth liposomes optimized by Taguchi design.  

PubMed

Abstract Stealth liposomes encapsulating oligonucleotides are considered as promising non-viral gene delivery carriers; however, general preparation procedures are not capable to encapsulate nucleic acids (NAs) efficiently. In this study, the lyophobic complexes of deoxythymidine20 oligonucleotide (dT20) and DOTAP were used instead of free dT20 for nano-encapsulation process by reverse phase evaporation method. Regarding the various factors that can potentially affect the liposome characteristics, Taguchi design was applied to analyze the simultaneous effects of factors comprising PEG-lipid (%), dT20/total lipid molar ratio, cholesterol (Chol%) and organic-to-aqueous phase ratio (o/w) at three levels. The response variables, hydrodynamic diameter, loading efficiency (LE%) and capacity (LC%), were studied by dynamic light scattering and ethidium bromide exclusion assay, respectively. The optimum condition described by minimum particle size as well as high LE% and LC% was obtained at 5% PEG-lipid, dT20/total lipid of 7, 20% Chol and o/w of 3 with an average size of 84?nm, LE%?=?83.4% and LC%?=?11.6%. Moreover, stability assessments in presence of heparin sulfate revealed the noticeable resistance, unlike DOTAP/dT20 lipoplexes, to premature release of NA. Transmission electron microscopy confirmed formation of discrete and circular vesicles encapsulating dT20. PMID:24960449

Tavakoli, Shirin; Tamaddon, Ali Mohammad; Golkar, Nasim; Samani, Soliman Mohammadi

2015-03-01

23

An Exploratory Exercise in Taguchi Analysis of Design Parameters: Application to a Shuttle-to-space Station Automated Approach Control System  

NASA Technical Reports Server (NTRS)

The chief goals of the summer project have been twofold - first, for my host group and myself to learn as much of the working details of Taguchi analysis as possible in the time allotted, and, secondly, to apply the methodology to a design problem with the intention of establishing a preliminary set of near-optimal (in the sense of producing a desired response) design parameter values from among a large number of candidate factor combinations. The selected problem is concerned with determining design factor settings for an automated approach program which is to have the capability of guiding the Shuttle into the docking port of the Space Station under controlled conditions so as to meet and/or optimize certain target criteria. The candidate design parameters under study were glide path (i.e., approach) angle, path intercept and approach gains, and minimum impulse bit mode (a parameter which defines how Shuttle jets shall be fired). Several performance criteria were of concern: terminal relative velocity at the instant the two spacecraft are mated; docking offset; number of Shuttle jet firings in certain specified directions (of interest due to possible plume impingement on the Station's solar arrays), and total RCS (a measure of the energy expended in performing the approach/docking maneuver). In the material discussed here, we have focused on single performance criteria - total RCS. An analysis of the possibility of employing a multiobjective function composed of a weighted sum of the various individual criteria has been undertaken, but is, at this writing, incomplete. Results from the Taguchi statistical analysis indicate that only three of the original four posited factors are significant in affecting RCS response. A comparison of model simulation output (via Monte Carlo) with predictions based on estimated factor effects inferred through the Taguchi experiment array data suggested acceptable or close agreement between the two except at the predicted optimum point, where a difference outside a rule-of-thumb bound was observed. We have concluded that there is most likely an interaction effect not provided for in the original orthogonal array selected as the basis for our experimental design. However, we feel that the data indicates that this interaction is a mild one and that inclusion of its effect will not alter the location of the optimum.

Deal, Don E.

1991-01-01

24

Design and implementation of an integrated Taguchi method for continuous assessment and improvement of manufacturing systems  

Microsoft Academic Search

The aim of this paper is to propose an integrated modeling framework that would help manufacturing managers for assessment,\\u000a ranking, and analysis of the manufacturing systems. The proposed framework is based on Taguchi method that ranks and analyzes\\u000a the manufacturing sectors by consolidating a set of management and organization productivity indicators. Sixty-one indicators\\u000a were identified and classified in five categories,

Ali Azadeh; S. Saman Miri-Nargesi; Seyed Mortezza Goldansaz; Neda Zoraghi

25

Experimental Design  

NSDL National Science Digital Library

What is Experimental Design? How Do I conduct an experiment? Is there a process to follow? This interactive lesson will allow for you to explore the questions above and many more Assignment #1: Scroll down to the link entitled "Steps of the Scientific Method " click on the link and go through the the Powerpoint on the Scientific Method.Scientific Method PowerPoint Assignment #2: This assisgnment has two parts. a) Click on " What is the Scientific Method" link and using the scientific method, solve the mystry. Please write your ...

Lunt, Mrs.

2010-06-07

26

Experimental Investigation of Parameters of CNC Turning by Taguchi based Grey Relational Analysis  

NASA Astrophysics Data System (ADS)

The AISI H13, a chromium based hot work tool Steel has a wide variety of applications in aluminum casting and extrusion dies, forging dies, hot nut tools, hot header dies, extrusion mandrels, plastic molds, cores, die holder blocks, hot press dies and specially hot work punches etc. In this study, the optimization of two response parameters (Surface roughness and Material Removal Rate) by three machining parameters (cutting speed, feed rate and depth of cut) is investigated in high speed turning of H13 in dry conditions. Taguchi's L'18 orthogonal array and analysis of variance (ANOVA) are used for individual optimization. The simultaneous optimization is done by Grey Relational Analysis approach. The different levels of all machining parameters are used and experiments are done on HMT STALLION-100 HS CNC lathe machine. The optimum condition for combined effects was found V5-F1-D1 and the optimal value of the surface roughness (Ra) comes out to be 0.85 (μm) and of MRR is 488.8 (mm³/sec). The optimum results are also verified with the help of confirmation experiments. Keywords: CNC Turning, O

Sharma, Pankaj; Bhambri, Kamaljeet

2013-03-01

27

Multi-response optimization using Taguchi design and principle component analysis for removing binary mixture of alizarin red and alizarin yellow from aqueous solution by nano ?-alumina  

NASA Astrophysics Data System (ADS)

The nanostructure of ?-alumina was used as an effective adsorbent for simultaneous removing of a mixture of alizarin red and alizarin yellow from aqueous solutions. The Taguchi design and principle component analysis were applied to explore effective parameters for achieving a higher adsorption capacity and removal percentage of the binary mixture containing alizarin red and alizarin yellow. Seven factors including temperature, contact time, initial pH value, the shaker rate, the sorbent dose, and initial concentrations of alizarin red and alizarin yellow in three levels were considered through the Taguchi technique. A L27 orthogonal array was used to determine the signal-to-noise ratio. Then, the removal percentage (R%) and adsorption capacity (q) of the above-mentioned dyes were transformed into an accurate S/N ratio. The Taguchi method indicates that the solution pH has the most contribution in controlling the removal percentage of alizarin red and alizarin yellow. Under optimal condition, the maximum removal percentages of 99% and 78.5%, and the capacity uptake of 54.4 and 39.0 mg g-1 were obtained for both alizarin red and alizarin yellow, respectively. Isotherm modeling and kinetic investigations showed that Langmuir, modified Langmuir, and pseudo-second-order models describe both the adsorption equilibrium and kinetic behavior well. The Fourier transform infrared analysis also firmly confirmed the involving active sites of nano ?-alumina in the adsorption process.

Zolgharnein, Javad; Asanjrani, Neda; Bagtash, Maryam; Azimi, Gholamhasan

28

Applying the Taguchi design for optimized formulation of sustained release gliclazide chitosan beads: an in vitro/in vivo study.  

PubMed

Gliclazide is a second generation of hypoglycemic sulfonylurea and acts selectively on pancreatic beta cell to control diabetes mellitus. The objective of this study was to produce a controlled release system of gliclazide using chitosan beads. Chitosan beads were produced by dispersion technique using tripolyphosphate (TPP) as gelating agent. The effects of process variables including chitosan molecular weight, concentration of chitosan and TPP, pH of TPP, and cross-linking time after addition of chitosan were evaluated by Taguchi design on the rate of drug release, mean release time (MRT), release efficiency (RE(8)%), and particle size of the beads. The blood glucose lowering effect of the beads was studied in normal and streptozotocin-diabetic rats. The optimized formulation CL(2)T(5)P(2)t(10) with about 31% drug loading, 2.4 h MRT, and 69.16% RE(8)% decreased blood glucose level in normal rats for 24 h compared to pure powder of gliclazide that lasted for just 10 h. PMID:19205888

Varshosaz, J; Tavakoli, N; Minayian, M; Rahdari, N

2009-01-01

29

Grey-based taguchi method for optimization of bead geometry in submerged arc bead-on-plate welding  

Microsoft Academic Search

A multi-response optimization problem has been developed in search of an optimal parametric combination to yield favorable\\u000a bead geometry of submerged arc bead-on-plate weldment. Taguchi’s L25 orthogonal array (OA) design and the concept of signal-to-noise\\u000a ratio (S\\/N ratio) have been used to derive objective functions to be optimized within experimental domain. The objective functions\\u000a have been selected in relation to

Saurav Datta; Asish Bandyopadhyay; Pradip Kumar Pal

2008-01-01

30

An Experimental Investigation into the Optimal Processing Conditions for the CO2 Laser Cladding of 20 MnCr5 Steel Using Taguchi Method and ANN  

NASA Astrophysics Data System (ADS)

This paper presents the prediction and evaluation of laser clad profile formed by means of CO2 laser applying Taguchi method and the artificial neural network (ANN). Laser cladding is one of the surface modifying technologies in which the desired surface characteristics of any component can be achieved such as good corrosion resistance, wear resistance and hardness etc. Laser is used as a heat source to melt the anti-corrosive powder of Inconel-625 (Super Alloy) to give a coating on 20 MnCr5 substrate. The parametric study of this technique is also attempted here. The data obtained from experiments have been used to develop the linear regression equation and then to develop the neural network model. Moreover, the data obtained from regression equations have also been used as supporting data to train the neural network. The artificial neural network (ANN) is used to establish the relationship between the input/output parameters of the process. The established ANN model is then indirectly integrated with the optimization technique. It has been seen that the developed neural network model shows a good degree of approximation with experimental data. In order to obtain the combination of process parameters such as laser power, scan speed and powder feed rate for which the output parameters become optimum, the experimental data have been used to develop the response surfaces.

Mondal, Subrata; Bandyopadhyay, Asish.; Pal, Pradip Kumar

2010-10-01

31

Taguchi methods in electronics: A case study  

NASA Technical Reports Server (NTRS)

Total Quality Management (TQM) is becoming more important as a way to improve productivity. One of the technical aspects of TQM is a system called the Taguchi method. This is an optimization method that, with a few precautions, can reduce test effort by an order of magnitude over conventional techniques. The Taguchi method is specifically designed to minimize a product's sensitivity to uncontrollable system disturbances such as aging, temperature, voltage variations, etc., by simultaneously varying both design and disturbance parameters. The analysis produces an optimum set of design parameters. A 3-day class on the Taguchi method was held at the Marshall Space Flight Center (MSFC) in May 1991. A project was needed as a follow-up after the class was over, and the motor controller was selected at that time. Exactly how to proceed was the subject of discussion for some months. It was not clear exactly what to measure, and design kept getting mixed with optimization. There was even some discussion about why the Taguchi method should be used at all.

Kissel, R.

1992-01-01

32

Taguchi analysis of drilling quality associated with core drill in drilling of composite material  

Microsoft Academic Search

The thrust force and surface roughness of core drill with drill parameters (grit size of diamond, thickness, feed rate and\\u000a spindle speed) in drilling carbon fiber reinforced plastic (CFRP) laminate was experimentally investigated in this study.\\u000a A L27 (313) orthogonal array and signal-to-noise (S\\/N) were employed to analyze the effect of drill parameters. Using Taguchi method\\u000a for design of a

C. C. Tsao

2007-01-01

33

Application of the Taguchi Method to the Optimization of the Submerged Arc Welding Process  

Microsoft Academic Search

Application of the Taguchi method to the optimization of the submerged arc welding process is reported. The Taguchi method is used to formulate the experimental layout, to analyze the effect of each welding parameter on welding performance, and to predict the optimal setting for each welding parameter. Experimental results are provided to confirm the effectiveness of this approach.

Y. S. Tarng; W. H. Yang

1998-01-01

34

Application of Taguchi methods to dual mixture ratio propulsion system optimization for SSTO vehicles  

NASA Technical Reports Server (NTRS)

The application of advanced technologies to future launch vehicle designs would allow the introduction of a rocket-powered, single-stage-to-orbit (SSTO) launch system early in the next century. For a selected SSTO concept, a dual mixture ratio, staged combustion cycle engine that employs a number of innovative technologies was selected as the baseline propulsion system. A series of parametric trade studies are presented to optimize both a dual mixture ratio engine and a single mixture ratio engine of similar design and technology level. The effect of varying lift-off thrust-to-weight ratio, engine mode transition Mach number, mixture ratios, area ratios, and chamber pressure values on overall vehicle weight is examined. The sensitivity of the advanced SSTO vehicle to variations in each of these parameters is presented, taking into account the interaction of each of the parameters with each other. This parametric optimization and sensitivity study employs a Taguchi design method. The Taguchi method is an efficient approach for determining near-optimum design parameters using orthogonal matrices from design of experiments (DOE) theory. Using orthogonal matrices significantly reduces the number of experimental configurations to be studied. The effectiveness and limitations of the Taguchi method for propulsion/vehicle optimization studies as compared to traditional single-variable parametric trade studies is also discussed.

Stanley, Douglas O.; Unal, Resit; Joyner, C. R.

1992-01-01

35

Simulation reduction using the Taguchi method  

NASA Technical Reports Server (NTRS)

A large amount of engineering effort is consumed in conducting experiments to obtain information needed for making design decisions. Efficiency in generating such information is the key to meeting market windows, keeping development and manufacturing costs low, and having high-quality products. The principal focus of this project is to develop and implement applications of Taguchi's quality engineering techniques. In particular, we show how these techniques are applied to reduce the number of experiments for trajectory simulation of the LifeSat space vehicle. Orthogonal arrays are used to study many parameters simultaneously with a minimum of time and resources. Taguchi's signal to noise ratio is being employed to measure quality. A compromise Decision Support Problem and Robust Design are applied to demonstrate how quality is designed into a product in the early stages of designing.

Mistree, Farrokh; Lautenschlager, Ume; Erikstad, Stein Owe; Allen, Janet K.

1993-01-01

36

Experimental Design (Industrial DOE)  

NSDL National Science Digital Library

This site, created by StatSoft, Inc., provides detailed discussions of many different types of experimental designs and examples with tables, graphs, and links to other detailed sites. The page combines text and images to help users better understand the theories presented. Overall, this is a complex website with many different areas to explore in the world of statistics.

2008-12-22

37

Optimisation of Lime-Soda process parameters for reduction of hardness in aqua-hatchery practices using Taguchi methods.  

PubMed

This paper presents the optimisation of Lime-Soda process parameters for the reduction of hardness in aqua-hatchery practices in the context of M. rosenbergii. The fresh water in the development of fisheries needs to be of suitable quality. Lack of desirable quality in available fresh water is generally the confronting restraint. On the Indian subcontinent, groundwater is the only source of raw water, having varying degree of hardness and thus is unsuitable for the fresh water prawn hatchery practices (M. rosenbergii). In order to make use of hard water in the context of aqua-hatchery, Lime-Soda process has been recommended. The efficacy of the various process parameters like lime, soda ash and detention time, on the reduction of hardness needs to be examined. This paper proposes to determine the parameter settings for the CIFE well water, which is pretty hard by using Taguchi experimental design method. Orthogonal Arrays of Taguchi, Signal-to-Noise Ratio, the analysis of variance (ANOVA) have been applied to determine their dosage and analysed for their effect on hardness reduction. The tests carried out with optimal levels of Lime-Soda process parameters confirmed the efficacy of the Taguchi optimisation method. Emphasis has been placed on optimisation of chemical doses required to reduce the total hardness using Taguchi method and ANOVA, to suit the available raw water quality for aqua-hatchery practices, especially for fresh water prawn M. rosenbergii. PMID:24749379

Yavalkar, S P; Bhole, A G; Babu, P V Vijay; Prakash, Chandra

2012-04-01

38

Parameter optimization of the fungicide (Vapam) sorption onto soil modified with clinoptilolite by Taguchi method.  

PubMed

This study employs the Taguchi optimization methodology to optimize the effective parameters for the pesticide (Vapam) sorption onto soil modified with natural zeolite (clinoptilolite). The experimental factors and their ranges chosen for determination of the effective parameters were: initial Vapam concentration (0.4-1.6 mg/L), initial pH of the pesticide solution (2-12), the percentage of clinoptilolite in the modified soil (0-6 %), temperature (15-35°C) and shaking time (2-24 h). The orthogonal array (OA) L(16) and the bigger the better response category of the Taguchi method were selected to determine the optimum conditions: initial Vapam concentration (1.2 mg/L), initial pH of the pesticide solution (2), the percentage of clinoptilolite in the modified soil (4 %), temperature (15°C) and shaking time (2 h). The results showed that in comparison with other parameters, the initial Vapam concentration was the most effective one for the sorption of this pesticide onto soil, modified with clinoptilolite. Moreover, after determining the optimum levels of the sorption process parameters, confirmation experiments were performed to prove the effectiveness of the Taguchi's experimental design methodology. PMID:20967667

Azizi, Seyed N; Asemi, Neda

2010-11-01

39

Cell Membrane Experimental Design  

NSDL National Science Digital Library

The final activity of this unit, which integrates the Keepers of the Gate unit through the Go Public challenge, involves students taking part in experimental design. They design a lab that answers the challenge question: "You are spending the night with your grandmother when your throat starts to feel sore. Your grandma tells you to gargle with salt water and it will feel much better. Thinking this is an old wive's tale, you scoff, but when you try it later that night it works! Why?" Students must have their plan approved by the instructor before they begin. A formal lab write-up is due as part of the laboratory investigation.

2014-09-18

40

Preparation of a crosslinked poly(acrylic acid) based new dehydrating agent by using the taguchi method  

Microsoft Academic Search

A new crosslinked, poly(acrylic acid)-based, dehydrating agent was synthesized through solution polymerization. The Taguchi\\u000a method, a robust experimental design, was adopted to optimize the synthetic conditions based on the moisture and water absorbing\\u000a capacities of the dehydrating agent. The method applied for the experiment was a standard L27 (38) orthogonal array with eight parameters and three levels. By analyzing the

Jun-Kyu Kim; Yang-Kyoo Han

2008-01-01

41

Study on interaction between palladium(??)-Linezolid chelate with eosin by resonance Rayleigh scattering, second order of scattering and frequency doubling scattering methods using Taguchi orthogonal array design.  

PubMed

Linezolid reacted with palladium to form 1:1 binary cationic chelate which further reacted with eosin dye to form 1:1 ternary ion association complex at pH 4 of Walpole's acetate buffer in the presence of methyl cellulose. As a result not only absorption spectra were changed but Resonance Rayleigh Scattering (RRS), Second-order Scattering (SOS) and Frequency Doubling Scattering (FDS) intensities were greatly enhanced. The analytical wavelengths of RRS, SOS and FDS (?ex/?em) of ternary complex were located at 538 nm/538nm, 240 nm/480 nm and 660 nm/330 nm, respectively. The linearity range for RRS, SOS and FDS methods were 0.01-0.5 ?g mL(-1), 0.1-2 ?g mL(-1) and 0.2-1.8 ?g mL(-1), respectively. The sensitivity order of three methods was as RRS>SOS>FDS. Accuracy of all methods were determined by recovery studies and showed recovery between 98% and 102%. Intraday and inter day precision were checked for all methods and %RSD was found to be less than 2 for all methods. The effects of foreign substances were tested on RRS method and it showed the method had good selectivity. For optimization of process parameter, Taguchi orthogonal array design L8(2(4)) was used and ANOVA was adopted to determine the statistically significant control factors that affect the scattering intensities of methods. The reaction mechanism, composition of ternary ion association complex and reasons for scattering intensity enhancement was discussed in this work. PMID:24299978

Thakkar, Disha; Gevriya, Bhavesh; Mashru, R C

2014-03-25

42

Study on interaction between palladium(??)-Linezolid chelate with eosin by resonance Rayleigh scattering, second order of scattering and frequency doubling scattering methods using Taguchi orthogonal array design  

NASA Astrophysics Data System (ADS)

Linezolid reacted with palladium to form 1:1 binary cationic chelate which further reacted with eosin dye to form 1:1 ternary ion association complex at pH 4 of Walpole's acetate buffer in the presence of methyl cellulose. As a result not only absorption spectra were changed but Resonance Rayleigh Scattering (RRS), Second-order Scattering (SOS) and Frequency Doubling Scattering (FDS) intensities were greatly enhanced. The analytical wavelengths of RRS, SOS and FDS (?ex/?em) of ternary complex were located at 538 nm/538 nm, 240 nm/480 nm and 660 nm/330 nm, respectively. The linearity range for RRS, SOS and FDS methods were 0.01-0.5 ?g mL-1, 0.1-2 ?g mL-1 and 0.2-1.8 ?g mL-1, respectively. The sensitivity order of three methods was as RRS > SOS > FDS. Accuracy of all methods were determined by recovery studies and showed recovery between 98% and 102%. Intraday and inter day precision were checked for all methods and %RSD was found to be less than 2 for all methods. The effects of foreign substances were tested on RRS method and it showed the method had good selectivity. For optimization of process parameter, Taguchi orthogonal array design L8(24) was used and ANOVA was adopted to determine the statistically significant control factors that affect the scattering intensities of methods. The reaction mechanism, composition of ternary ion association complex and reasons for scattering intensity enhancement was discussed in this work.

Thakkar, Disha; Gevriya, Bhavesh; Mashru, R. C.

2014-03-01

43

Designing an Experimental "Accident"  

ERIC Educational Resources Information Center

Describes an experimental "accident" that resulted in much student learning, seeks help in the identification of nematodes, and suggests biology teachers introduce similar accidents into their teaching to stimulate student interest. (PEB)

Picker, Lester

1974-01-01

44

Taguchi Optimization of Pulsed Current GTA Welding Parameters for Improved Corrosion Resistance of 5083 Aluminum Welds  

NASA Astrophysics Data System (ADS)

In this study, the Taguchi method was used as a design of experiment (DOE) technique to optimize the pulsed current gas tungsten arc welding (GTAW) parameters for improved pitting corrosion resistance of AA5083-H18 aluminum alloy welds. A L9 (34) orthogonal array of the Taguchi design was used, which involves nine experiments for four parameters: peak current ( P), base current ( B), percent pulse-on time ( T), and pulse frequency ( F) with three levels was used. Pitting corrosion resistance in 3.5 wt.% NaCl solution was evaluated by anodic polarization tests at room temperature and calculating the width of the passive region (? E pit). Analysis of variance (ANOVA) was performed on the measured data and S/ N (signal to noise) ratios. The "bigger is better" was selected as the quality characteristic (QC). The optimum conditions were found as 170 A, 85 A, 40%, and 6 Hz for P, B, T, and F factors, respectively. The study showed that the percent pulse-on time has the highest influence on the pitting corrosion resistance (50.48%) followed by pulse frequency (28.62%), peak current (11.05%) and base current (9.86%). The range of optimum ? E pit at optimum conditions with a confidence level of 90% was predicted to be between 174.81 and 177.74 mVSCE. Under optimum conditions, the confirmation test was carried out, and the experimental value of ? E pit of 176 mVSCE was in agreement with the predicted value from the Taguchi model. In this regard, the model can be effectively used to predict the ? E pit of pulsed current gas tungsten arc welded joints.

Rastkerdar, E.; Shamanian, M.; Saatchi, A.

2013-04-01

45

Modified Artificial Diet for Rearing of Tobacco Budworm, Helicoverpa armigera, using the Taguchi Method and Derringer's Desirability Function  

PubMed Central

With the aim to improve the mass rearing feasibility of tobacco budworm, Helicoverpa armigera Hübner (Lepidoptera: Noctuidae), design of experimental methodology using Taguchi orthogonal array was applied. To do so, the effect of 16 ingredients of an artificial diet including bean, wheat germ powder, Nipagin, ascorbic acid, formaldehyde, oil, agar, distilled water, ascorbate, yeast, chloramphenicol, benomyl, penicillin, temperature, humidity, and container size on some biological characteristics of H. armigera was evaluated. The selected 16 factors were considered at two levels (32 experiments) in the experimental design. Among the selected factors, penicillin, container size, formaldehyde, chloramphenicol, wheat germ powder, and agar showed significant effect on the mass rearing performance. Derringer's desirability function was used for simultaneous optimization of mass rearing of tobacco budworm, H. armigera, on a modified artificial diet. Derived optimum operating conditions obtained by Derringer's desirability function and Taguchi methodology decreased larval period from 19 to 15.5 days (18.42 % improvement), decreased the pupal period from 12.29 to 11 days (10.49 % improvement), increased the longevity of adults from 14.51 to 21 days (44.72 % improvement), increased the number of eggs/female from 211.21 to 260, and increased egg hatchability from 54.2% to 72% (32.84 % improvement). The proposed method facilitated a systematic mathematical approach with a few well-defined experimental sets. PMID:23425103

Assemi, H.; Rezapanah, M.; Vafaei-Shoushtari, R.

2012-01-01

46

Optimizing Aqua Splicer Parameters for Lycra-Cotton Core Spun Yarn Using Taguchi Method  

NASA Astrophysics Data System (ADS)

In this paper, optimization of the aqua splicer parameters viz opening time, splicing time, feed arm code (i.e. splice length) and duration of water joining was carried out for 37 tex lycra-cotton core spun yarn for better retained splice strength (RSS%), splice abrasion resistance (RYAR%) and splice appearance (RYA%) using Taguchi experimental design. It is observed that as opening time, splicing time and duration of water joining increase, the RSS% and RYAR% increases, whereas increase in feed arm code leads to decrease in both. The opening time and feed arm code do not have significant effect on RYA%. The optimum RSS% of 92.02 % was obtained at splicing parameters of 350 ms opening time, 180 ms splicing time, 65 feed arm code and 600 ms duration of water joining.

Midha, Vinay Kumar; Hiremath, ShivKumar; Gupta, Vaibhav

2014-11-01

47

Animal husbandry and experimental design.  

PubMed

If the scientist needs to contact the animal facility after any study to inquire about husbandry details, this represents a lost opportunity, which can ultimately interfere with the study results and their interpretation. There is a clear tendency for authors to describe methodological procedures down to the smallest detail, but at the same time to provide minimal information on animals and their husbandry. Controlling all major variables as far as possible is the key issue when establishing an experimental design. The other common mechanism affecting study results is a change in the variation. Factors causing bias or variation changes are also detectable within husbandry. Our lives and the lives of animals are governed by cycles: the seasons, the reproductive cycle, the weekend-working days, the cage change/room sanitation cycle, and the diurnal rhythm. Some of these may be attributable to routine husbandry, and the rest are cycles, which may be affected by husbandry procedures. Other issues to be considered are consequences of in-house transport, restrictions caused by caging, randomization of cage location, the physical environment inside the cage, the acoustic environment audible to animals, olfactory environment, materials in the cage, cage complexity, feeding regimens, kinship, and humans. Laboratory animal husbandry issues are an integral but underappreciated part of investigators' experimental design, which if ignored can cause major interference with the results. All researchers should familiarize themselves with the current routine animal care of the facility serving them, including their capabilities for the monitoring of biological and physicochemical environment. PMID:25541541

Nevalainen, Timo

2014-01-01

48

Experimental Design and Some Threats to Experimental Validity: A Primer  

ERIC Educational Resources Information Center

Experimental designs are distinguished as the best method to respond to questions involving causality. The purpose of the present paper is to explicate the logic of experimental design and why it is so vital to questions that demand causal conclusions. In addition, types of internal and external validity threats are discussed. To emphasize the…

Skidmore, Susan

2008-01-01

49

The Experimental Design Ability Test (EDAT)  

ERIC Educational Resources Information Center

Higher education goals include helping students develop evidence based reasoning skills; therefore, scientific thinking skills such as those required to understand the design of a basic experiment are important. The Experimental Design Ability Test (EDAT) measures students' understanding of the criteria for good experimental design through their…

Sirum, Karen; Humburg, Jennifer

2011-01-01

50

From Cookbook to Experimental Design  

NSDL National Science Digital Library

Developing expertise, whether from cook to chef or from student to scientist, occurs over time and requires encouragement, guidance, and support. One key goal of an elementary science program should be to move students toward expertise in their ability to design investigative questions. The ability to design a testable question is difficult for novice science students and requires teachers to support students by using concrete strategies. This article promotes a tangible strategy teachers can use to help students design testable questions for experiments and discusses how the strategy can be used to help students design their own investigative questions.

Flannagan, Jenny S.; Mcmillan, Rachel

2009-02-01

51

Teaching the Taguchi method to industrial engineers  

Microsoft Academic Search

The Taguchi method (Tm) is a powerful problem solving technique for improving process performance, yield and productivity. It reduces scrap rates, rework costs and manufacturing costs due to excessive variability in processes. However, its application by industrial engineers in the UK is limited, in part due to the inadequate statistical education of engineers. This paper presents a simple experiment which

Jiju Antony; Frenie Jiju Antony

2001-01-01

52

Design and Experimental Capstone: An Integrated Experience  

NSDL National Science Digital Library

We report on student outcomes across three phases in the development of the BME senior capstone experience. The BME department provides a comprehensive capstone experience to its seniors. All students enroll in a two-course, team-based, device design capstone sequence and a concurrent two-course, team-based, experimental research capstone sequence. The goal of the device design capstone is to advance intellectual property while providing a multidisciplinary design experience. In the first course of the sequence, the teams are presented with a clinical problem and are expected to conceive, design, prototype and evaluate devices with innovative solutions. The course emphasizes information gathering, establishing requirements, concept development, and evaluation. In the second course in the sequence, a verification plan is generated and implemented. The goal of the experimental research capstone sequence is to introduce students to the design and conduct of a pilot study involving human subjects. To this end, students develop a hypothesis, design an experimental protocol to test the hypothesis, conduct an experiment or survey, and use an appropriate statistical analysis of the data. The course also requires students to design an Informed Consent form, adopt high ethical standards for research involving human subjects, and generate a scientific manuscript to report the results. We found that a close integration between experimental methods of testing/data collection was critical in the initial and final stages of design. Those teams that had an integrated design and experimental capstone experience produced better designs than those teams that had separate experiences.

Johnson, Jeffrey

53

The photocatalytic degradation of cationic surfactant from wastewater in the presence of nano-zinc oxide using Taguchi method  

NASA Astrophysics Data System (ADS)

The photocatalytic degradation of cetyl pyridinium chloride (CPC) has been investigated in aqueous phase using ultraviolet (UV) and ZnO nanopowder. Kinetic analysis showed that the extent of surfactant photocatalytic degradation can be fitted with pseudo-first-order model and photochemical elimination of CPC could be studied by Taguchi method. Our experimental design was based on testing five factors, i.e., dosage of K2S2O8, concentration of CPC, amount of ZnO, irradiation time and initial pH. Each factor was tested at four levels. The optimum parameters were found to be pH 5.0; amount of ZnO 11 mg; K2S2O8 3 mM; CPC 10 mg/L; irradiation time, 8 h.

Giahi, M.; Moradidoost, A.; Bagherinia, M. A.; Taghavi, H.

2013-12-01

54

SAMPLING DECISIONS IN OPTIMUM EXPERIMENTAL DESIGN IN ...  

E-print Network

determined such that a follow-up parameter estimation yields accurate results for model parameters. In this paper we use the interpretation of OED as optimal control problems with a very ...... experimental design in DAE systems, J. Comput.

ssager

55

Taguchi Method Applied in Optimization of Shipley SJR 5740 Positive Resist Deposition  

NASA Technical Reports Server (NTRS)

Taguchi Methods of Robust Design presents a way to optimize output process performance through an organized set of experiments by using orthogonal arrays. Analysis of variance and signal-to-noise ratio is used to evaluate the contribution of each of the process controllable parameters in the realization of the process optimization. In the photoresist deposition process, there are numerous controllable parameters that can affect the surface quality and thickness of the final photoresist layer.

Hui, A.; Blosiu, J. O.; Wiberg, D. V.

1998-01-01

56

Optimization of EDM process for multiple performance characteristics using Taguchi method and Grey relational analysis  

Microsoft Academic Search

Electrical discharge machining (EDM) is one of the most extensively used non-conventional material removal processes. The\\u000a Taguchi method has been utilized to determine the optimal EDM conditions in several industrial fields. The method, however,\\u000a was designed to optimize only a single performance characteristic. To remove that limitation, the Grey relational analysis\\u000a theory has been used to resolve the complicated interrelationships

Jong Hyuk Jung; Won Tae Kwon

2010-01-01

57

Choosing an Experimental Design (Engineering Statistics Handbook)  

NSDL National Science Digital Library

This section of the Engineering Statistics Handbook, created by authors Alan Heckert and James Filliben of the National Institute of Standards and Technology, describes in detail the process of choosing an experimental design to obtain the results you need. The basic designs an engineer needs to know about are described in detail. Overall, this is a great resource for anyone interested in either engineering or mathematics.

Filliben, James; Heckert, Alan

2008-12-31

58

Optimal Experimental Design for Model Discrimination  

ERIC Educational Resources Information Center

Models of a psychological process can be difficult to discriminate experimentally because it is not easy to determine the values of the critical design variables (e.g., presentation schedule, stimulus structure) that will be most informative in differentiating them. Recent developments in sampling-based search methods in statistics make it…

Myung, Jay I.; Pitt, Mark A.

2009-01-01

59

Application of Taguchi Method in the Optimization of ARC-Carbon Nanotube Fabrication  

NASA Astrophysics Data System (ADS)

Carbon nanotube, a new form of element carbon, is composed of graphene sheets rolled into closed concentric cylinders with diameter of the order of nanometers and length of micrometers. Since its discovery in 1991, extensive applications have been found in physical, chemical and material science fields. Due to its novel electronic structure, in electrochemical area, many researches have been carried out to study its electrocatalytic behavior towards many substances such as O2, H2O2 and NADH utilizing its ability of fast electron transfer. Particularly, carbon nanotube's biocompatibility together with its catalytic ability to H2O2 and NADH opened its application in fabricating excellent amperometric nano(bio)sensors. Arc-in-liquid method has been developed to synthesize many kinds of nano-carbon structures such as carbon onions, carbon nanohorns and carbon nanotubes. This technique is considered as a low cost method because it does not require any expensive equipment. In here, this method was used for fabrication of nanotubes, and then a modified acid treatment method applied for purification stage. To optimize the synthesis, four various factors (voltage, current, catalyst and plasma) which are mostly affected on the carbon nanotubes were introduced to the Taguchi software in four levels. This statistical experimental design can determine the effect of the factors on characteristic properties and the optimal conditions of factors.

Jahanshahi, M.; Jahan-Bakhsh, R.; Solmaz, H.; Razieh, J. S.

2007-08-01

60

Rational Experimental Design for Electrical Resistivity Imaging  

NASA Astrophysics Data System (ADS)

Over the past several decades advances in the acquisition and processing of electrical resistivity data, through multi-channel acquisition systems and new inversion algorithms, have greatly increased the value of these data to near-surface environmental and hydrological problems. There has, however, been relatively little advancement in the design of actual surveys. Data acquisition still typically involves using a small number of traditional arrays (e.g. Wenner, Schlumberger) despite a demonstrated improvement in data quality from the use of non-standard arrays. While optimized experimental design has been widely studied in applied mathematics and the physical and biological sciences, it is rarely implemented for non-linear problems, such as electrical resistivity imaging (ERI). We focus specifically on using ERI in the field for monitoring changes in the subsurface electrical resistivity structure. For this application we seek an experimental design method that can be used in the field to modify the data acquisition scheme (spatial and temporal sampling) based on prior knowledge of the site and/or knowledge gained during the imaging experiment. Some recent studies have investigated optimized design of electrical resistivity surveys by linearizing the problem or with computationally-intensive search algorithms. We propose a method for rational experimental design based on the concept of informed imaging, the use of prior information regarding subsurface properties and processes to develop problem-specific data acquisition and inversion schemes. Specifically, we use realistic subsurface resistivity models to aid in choosing source configurations that maximize the information content of our data. Our approach is based on first assessing the current density within a region of interest, in order to provide sufficient energy to the region of interest to overcome a noise threshold, and then evaluating the direction of current vectors, in order to maximize the information content of the source configurations. This approach requires minimal computational power, and, thus, it can be implemented in the field as information is acquired, allowing for modification of the current experimental design. We compare, through numerical modeling, results from arrays identified by this algorithm to those from traditional arrays for the case where we have a good starting model of the subsurface. We then test the performance of selected arrays in the case of uncertainty in the resistivity model and noise in the data. In all cases, our method provides comparable or superior results at low computational cost, providing a useful framework for rational experimental design.

Mitchell, V.; Pidlisecky, A.; Knight, R.

2008-12-01

61

Optimization of Welding Parameters of Submerged Arc Welding Using Analytic Hierarchy Process (AHP) Based on Taguchi Technique  

NASA Astrophysics Data System (ADS)

The present paper reports a new procedure using an analytic hierarchy process (AHP) based Taguchi method for the selection of the best welding parameters to fabricate submerged arc welding of plain carbon steel. Selection of best welding parameters is an unstructured decision problem involving process parameters for multiple weldments. In the present investigation, three process parameter variables i.e. wire feed rate (Wf), stick out (So) and traverse speed (Ts) and the three response parameters i.e. penetration, bead width and bead reinforcement have been considered. The objective of the present work is thus to improve the quality of the welded elements by using AHP analysis based Taguchi method. Taguchi L16 orthogonal array is used to perform with less number of experimental runs. Taguchi approach is insufficient to solve a multi response optimization problem. In order to overcome this limitation, a multi criteria decision making method, AHP is applied in the present study. The optimal condition to have a quality weld (i.e. bead geometry) is found at 210 mm/min of wire feed rate, 15 mm of stick out and 0.75 m/min of traverse speed and also observed that the effect of wire feed rate on the overall bead geometry properties is more significant than other welding parameters. Finally, a confirmatory test has been carried out to verify the optimal setting so obtained.

Sarkar, A.; Roy, J.; Majumder, A.; Saha, S. C.

2014-04-01

62

A Novel GA-Taguchi-Based Feature Selection Method  

Microsoft Academic Search

This work presents a novel GA-Taguchi-based feature selection method. Genetic algorithms are utilized with randomness for\\u000a “global search” of the entire search space of the intractable search problem. Various genetic operations, including crossover,\\u000a mutation, selection and replacement are performed to assist the search procedure in escaping from sub-optimal solutions. In\\u000a each iteration in the proposed nature-inspired method, the Taguchi methods

Cheng-hong Yang; Chi-chun Huang; Kuo-chuan Wu; Hsin-yun Chang

2008-01-01

63

Surface quality evaluation in ultrasonic drilling through the Taguchi technique  

Microsoft Academic Search

Ultrasonic drilling of commercially pure titanium and titanium alloy (Ti-6Al-4v) was investigated in this study. During the\\u000a experiments, process parameters such as work piece, grit size, slurry concentration, power rating and tools were changed to\\u000a explore their effect on the surface roughness. Taguchi’s technique was applied to obtain an optimal setting of ultrasonic\\u000a drilling (USD) process parameters. Average surface roughness

A. Dvivedi; P. Kumar

2007-01-01

64

Application of Taguchi based Response Surface Method (TRSM) for Optimization of Multi Responses in Drilling Al/SiC/Al2O3 Hybrid Composite  

NASA Astrophysics Data System (ADS)

The emerging industrial applications of second generation hybrid composites demand an organised study of their drilling characteristics as drilling is an essential metal removal process in the final fabrication stage. In the present work, surface finish and burr height were observed while drilling Al6061/SiC/Al2O3 composite for various combinations of drilling parameters like the feed rate, spindle speed and point angle of tool. The experimental trials were designed by L18 orthogonal array and Taguchi based response surface method was presented for optimizing the drilling parameters. The significant improvements in the responses observed for the optimal parameter setting has validated the TRSM approach permitting its application in other areas of manufacturing.

Adalarasan, R.; Santhanakumar, M.

2015-01-01

65

Bread Making: Classic Biotechnology and Experimental Design  

NSDL National Science Digital Library

Bread making activities can help students meet local and national standards for scientific inquiry, experimental design, and problem solving. In the first activity, students make and observe yeast solutions. Then they predict what might happen when the recipe is modified and conduct invesitigations. The subsequent investigations increase the level of student input and encourages students to practice the skills before using them outside of the classroom. The final assignment draws upon and expands the skills practiced in class with an at-home investigation.

Daniel L. Sitzman

2003-01-01

66

Experimental Design for the LATOR Mission  

NASA Technical Reports Server (NTRS)

This paper discusses experimental design for the Laser Astrometric Test Of Relativity (LATOR) mission. LATOR is designed to reach unprecedented accuracy of 1 part in 10(exp 8) in measuring the curvature of the solar gravitational field as given by the value of the key Eddington post-Newtonian parameter gamma. This mission will demonstrate the accuracy needed to measure effects of the next post-Newtonian order (near infinity G2) of light deflection resulting from gravity s intrinsic non-linearity. LATOR will provide the first precise measurement of the solar quadrupole moment parameter, J(sub 2), and will improve determination of a variety of relativistic effects including Lense-Thirring precession. The mission will benefit from the recent progress in the optical communication technologies the immediate and natural step above the standard radio-metric techniques. The key element of LATOR is a geometric redundancy provided by the laser ranging and long-baseline optical interferometry. We discuss the mission and optical designs, as well as the expected performance of this proposed mission. LATOR will lead to very robust advances in the tests of Fundamental physics: this mission could discover a violation or extension of general relativity, or reveal the presence of an additional long range interaction in the physical law. There are no analogs to the LATOR experiment; it is unique and is a natural culmination of solar system gravity experiments.

Turyshev, Slava G.; Shao, Michael; Nordtvedt, Kenneth, Jr.

2004-01-01

67

Optimization of Processing Parameters During Laser Cladding of ZE41AT5 Magnesium Alloy Castings Using Taguchi Method  

Microsoft Academic Search

A continuous wave 4 kW Nd:YAG laser welding system was employed to clad single beads on machined 6.2-mm thick ZE41A-T5 aerospace magnesium alloy sand castings using nominal 1.6-mm filler rods of the parent metal. Based on the quality criterion of minimum dilution ratio, the Taguchi experimental method was used to optimize different process parameters and to identify the dominating factors. It

X. Cao; M. Xiao; M. Jahazi; J. Fournier; M. Alain

2008-01-01

68

Design and Experimental Applications of Acoustic Metamaterials  

NASA Astrophysics Data System (ADS)

Acoustic metamaterials are engineered materials that were extensively investigated over the last years mainly because they promise properties otherwise hard or impossible to find in nature. Consequently, they open the door for improved or completely new applications (e.g. acoustic superlens that can exceed the diffraction limit in imaging or acoustic absorbing panels with higher transmission loss and smaller thickness than regular absorbers). Our objective is to surpass the limited frequency operating range imposed by the resonant mechanism that s1ome of these materials have. In addition, we want acoustic metamaterials that could be experimentally demonstrated and used to build devices with overall performances better than the previous ones reported in the literature. Here, we start by focusing on the need of engineered metamaterials in general and acoustic metamaterials in particular. Also, the similarities between electromagnetic metamaterials and acoustic metamaterials and possible ways to realize broadband acoustic metamaterials are briefly discussed. Then, we present the experimental realization and characterization of a two-dimensional (2D) broadband acoustic metamaterial with strongly anisotropic effective mass density. We use this metamaterial to realize a 2D broadband gradient index acoustic lens in air. Furthermore, we optimize the lens design by improving each unit cell's performance and we also realize a 2D acoustic ground cloak in air. In addition, we explore the performance of some novel applications (a 2D acoustic black hole and a three-dimensional acoustic cloak) using the currently available acoustic metamaterials. In order to overcome the limitations of our designs, we approach the active acoustic metamaterials path, which offers a broader range for the material parameters values and a better control over them. We propose two structures which contain a sensing element (microphone) and an acoustic driver (piezoelectric membrane or speaker). The material properties are controlled by tuning the response of the unit cell to the incident wave. Several samples with interesting effective mass density and bulk modulus are presented. We conclude by suggesting few natural directions that could be followed for the future research based on the theoretical and experimental results presented in this work.

Zigoneanu, Lucian

69

Laboratory Experimental Design of Molecular Cloud Implosions  

NASA Astrophysics Data System (ADS)

The interaction of ionizing radiation with its surrounding medium is a ubiquitous issue in astrophysics. Although the interaction can occur in many environments, the interaction of an ionization front with a molecular cloud is of particular interest. Material ablated form the cloud can form turbulent structure [Peters et al, 2008] and coupled with the radiatively-driven implosion of the cloud can have important consequences in stellar formation. Our understanding of stellar formation is based on computer simulations and models. To improve our understanding of these models, data is required. We present the design of an experiment to study the interaction of an ionization front with a high density sphere, which acts as a surrogate for the molecular cloud. Irradiating a high-Z foil with laser beams generates the ionization front. The ionization front will propagate in a low density medium before interacting with the sphere. We will present our experimental design along with initial simulations. This work is funded by the NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas, grant number DE-FG52-09NA29548.

Keiter, Paul; Stone, James; Trantham, Matt; Malamud, Guy; Klein, Sallee

2012-10-01

70

Web Based Learning Support for Experimental Design in Molecular Biology.  

ERIC Educational Resources Information Center

An important learning goal of a molecular biology curriculum is a certain proficiency level in experimental design. Currently students are confronted with experimental approaches in textbooks, in lectures and in the laboratory. However, most students do not reach a satisfactory level of competence in the design of experimental approaches. This…

Wilmsen, Tinri; Bisseling, Ton; Hartog, Rob

71

[Treatment of bedsores--combination of therapies depended the experimental design method].  

PubMed

The treatment of bedsores is a particular problem in geriatric medicine. We selected standard drugs that may be effective for the decubitus ulcer, and investigated combination therapy to develop efficient treatment The subjects were 16 patients in whom the grade of the bedsore was evaluated as II to IV according to the Shea's depth classification. Treatment was performed while all patients were on air mats. We selected drugs and treatment methods based on the previously established experimental design of Taguchi. Based on this, we created and adapted 16 different component combination treatment programs in accordance with the L16 rectangular cross table. The following component factors were adopted: A: types of covering substances on the wound surface (Elase ointment, isodine sugar, isodine gel solcoseryl ointment); B: Isalopan powder; C: Spray of 10 ml physiological saline containing 500 microg of prostaglandin (concentration 0.005%); D: daily number of treatments; and F: presence or absence of tapping. We serially measured the wound surface area as an index of the speed of wound healing, and measured the interval (day) until the area decreased to one half of the original size (T1/2, half life). We analyzed data on one combination treatment each in 16 patients. Analysis of variance of the above factors showed significant F values for factors A, B, D and F. The contribution rates for factors A, B, D and F were 37.84%, 8.47%, 14.98% and 13.81%, respectively. The error term (e) was 16.37%. Optimal results were seen in the groups in which solcoseryl ointment had been applied twice a day. In this study, prostaglandin, which had been anticipated to be effective, did not show any effects. The error term (e) suggests the presence of other healing factors including individual differences. Concerning this point, it well be necessary to examine a larger number of patients in the future. With ointment treatment alone, without using an air mat, it was confirmed that bedsore area reduction was extremely unstable. Decompression of the affected part may be a basic prevention factor and essential treatment of bedsores. PMID:15732367

Miyaji, Hiroko; Sakurai, Hirofumi; Kikawada, Masayuki; Yamaguchi, Katsuhiko; Kimura, Akihiro; Fujiwara, Takayuki; Imada, Nobuo; Imai, Mihoko; Iwamoto, Toshihiko; Takasaki, Masaru

2005-01-01

72

SVM-RFE Based Feature Selection and Taguchi Parameters Optimization for Multiclass SVM Classifier  

PubMed Central

Recently, support vector machine (SVM) has excellent performance on classification and prediction and is widely used on disease diagnosis or medical assistance. However, SVM only functions well on two-group classification problems. This study combines feature selection and SVM recursive feature elimination (SVM-RFE) to investigate the classification accuracy of multiclass problems for Dermatology and Zoo databases. Dermatology dataset contains 33 feature variables, 1 class variable, and 366 testing instances; and the Zoo dataset contains 16 feature variables, 1 class variable, and 101 testing instances. The feature variables in the two datasets were sorted in descending order by explanatory power, and different feature sets were selected by SVM-RFE to explore classification accuracy. Meanwhile, Taguchi method was jointly combined with SVM classifier in order to optimize parameters C and ? to increase classification accuracy for multiclass classification. The experimental results show that the classification accuracy can be more than 95% after SVM-RFE feature selection and Taguchi parameter optimization for Dermatology and Zoo databases. PMID:25295306

Huang, Mei-Ling; Hung, Yung-Hsiang; Lee, W. M.; Li, R. K.; Jiang, Bo-Ru

2014-01-01

73

SVM-RFE based feature selection and Taguchi parameters optimization for multiclass SVM classifier.  

PubMed

Recently, support vector machine (SVM) has excellent performance on classification and prediction and is widely used on disease diagnosis or medical assistance. However, SVM only functions well on two-group classification problems. This study combines feature selection and SVM recursive feature elimination (SVM-RFE) to investigate the classification accuracy of multiclass problems for Dermatology and Zoo databases. Dermatology dataset contains 33 feature variables, 1 class variable, and 366 testing instances; and the Zoo dataset contains 16 feature variables, 1 class variable, and 101 testing instances. The feature variables in the two datasets were sorted in descending order by explanatory power, and different feature sets were selected by SVM-RFE to explore classification accuracy. Meanwhile, Taguchi method was jointly combined with SVM classifier in order to optimize parameters C and ? to increase classification accuracy for multiclass classification. The experimental results show that the classification accuracy can be more than 95% after SVM-RFE feature selection and Taguchi parameter optimization for Dermatology and Zoo databases. PMID:25295306

Huang, Mei-Ling; Hung, Yung-Hsiang; Lee, W M; Li, R K; Jiang, Bo-Ru

2014-01-01

74

Dysprosium sorption by polymeric composite bead: Robust parametric optimization using Taguchi method.  

PubMed

Polyethersulfone-based beads encapsulating di-2-ethylhexyl phosphoric acid have been synthesized and evaluated for the recovery of rare earth values from the aqueous media. Percentage recovery and the sorption behavior of Dy(III) have been investigated under wide range of experimental parameters using these beads. Taguchi method utilizing L-18 orthogonal array has been adopted to identify the most influential process parameters responsible for higher degree of recovery with enhanced sorption of Dy(III) from chloride medium. Analysis of variance indicated that the feed concentration of Dy(III) is the most influential factor for equilibrium sorption capacity, whereas aqueous phase acidity influences the percentage recovery most. The presence of polyvinyl alcohol and multiwalled carbon nanotube modified the internal structure of the composite beads and resulted in uniform distribution of organic extractant inside polymeric matrix. The experiment performed under optimum process conditions as predicted by Taguchi method resulted in enhanced Dy(III) recovery and sorption capacity by polymeric beads with minimum standard deviation. PMID:25660520

Yadav, Kartikey K; Dasgupta, Kinshuk; Singh, Dhruva K; Varshney, Lalit; Singh, Harvinderpal

2015-03-01

75

The Implications of "Contamination" for Experimental Design in Education  

ERIC Educational Resources Information Center

Experimental designs that randomly assign entire clusters of individuals (e.g., schools and classrooms) to treatments are frequently advocated as a way of guarding against contamination of the estimated average causal effect of treatment. However, in the absence of contamination, experimental designs that randomly assign intact clusters to…

Rhoads, Christopher H.

2011-01-01

76

Conceptual design report, CEBAF basic experimental equipment  

SciTech Connect

The Continuous Electron Beam Accelerator Facility (CEBAF) will be dedicated to basic research in Nuclear Physics using electrons and photons as projectiles. The accelerator configuration allows three nearly continuous beams to be delivered simultaneously in three experimental halls, which will be equipped with complementary sets of instruments: Hall A--two high resolution magnetic spectrometers; Hall B--a large acceptance magnetic spectrometer; Hall C--a high-momentum, moderate resolution, magnetic spectrometer and a variety of more dedicated instruments. This report contains a short description of the initial complement of experimental equipment to be installed in each of the three halls.

NONE

1990-04-13

77

Experimental design for sternocleidomastoid muscle stress measurement  

Microsoft Academic Search

In this paper we assess the sternocleidomastoid muscle stress with two experimental studies to evaluate the developed smart neck support system. The first study involving head rotation angle and sternocleidomastoid muscle (SCM) electromyography (EMG) activity. This (descriptive) study extends efforts from different authors to assess the isometric strength of SCM, in which the experiment is carried out in relation to

Chee Fai Tan; Wei Chen; Matthias Rauterberg

2010-01-01

78

Irradiation Design for an Experimental Murine Model  

NASA Astrophysics Data System (ADS)

In radiotherapy and stereotactic radiosurgery, small animal experimental models are frequently used, since there are still a lot of unsolved questions about the biological and biochemical effects of ionizing radiation. This work presents a method for small-animal brain radiotherapy compatible with a dedicated 6MV Linac. This rodent model is focused on the research of the inflammatory effects produced by ionizing radiation in the brain. In this work comparisons between Pencil Beam and Monte Carlo techniques, were used in order to evaluate accuracy of the calculated dose using a commercial planning system. Challenges in this murine model are discussed.

Ballesteros-Zebadúa, P.; Lárraga-Gutierrez, J. M.; García-Garduño, O. A.; Rubio-Osornio, M. C.; Custodio-Ramírez, V.; Moreno-Jimenez, S.; Suarez-Campos, J. E.; Paz, C.; Celis, M. A.

2010-12-01

79

Irradiation Design for an Experimental Murine Model  

SciTech Connect

In radiotherapy and stereotactic radiosurgery, small animal experimental models are frequently used, since there are still a lot of unsolved questions about the biological and biochemical effects of ionizing radiation. This work presents a method for small-animal brain radiotherapy compatible with a dedicated 6MV Linac. This rodent model is focused on the research of the inflammatory effects produced by ionizing radiation in the brain. In this work comparisons between Pencil Beam and Monte Carlo techniques, were used in order to evaluate accuracy of the calculated dose using a commercial planning system. Challenges in this murine model are discussed.

Ballesteros-Zebadua, P.; Moreno-Jimenez, S.; Suarez-Campos, J. E.; Celis, M. A. [Unidad de Radiocirugia, Instituto Nacional de Neurologia y Neurocirugia Insurgentes Sur 3677. Col. La Fama, C.P. 14269, Tlalpan, Mexico, D.F. (Mexico); Larraga-Gutierrez, J. M.; Garcia-Garduno, O. A. [Laboratorio de Fisica Medica, Instituto Nacional de Neurologia y Neurocirugia Insurgentes Sur 3677. Col. La Fama, C.P. 14269, Tlalpan, Mexico, D.F. (Mexico); Rubio-Osornio, M. C.; Custodio-Ramirez, V.; Paz, C. [Laboratorio de Neurofisiologia, Instituto Nacional de Neurologia y Neurocirugia Insurgentes Sur 3677. Col. La Fama, C.P. 14269, Tlalpan, Mexico, D.F. (Mexico)

2010-12-07

80

Experimental Design for Vector Output Systems  

PubMed Central

We formulate an optimal design problem for the selection of best states to observe and optimal sampling times for parameter estimation or inverse problems involving complex nonlinear dynamical systems. An iterative algorithm for implementation of the resulting methodology is proposed. Its use and efficacy is illustrated on two applied problems of practical interest: (i) dynamic models of HIV progression and (ii) modeling of the Calvin cycle in plant metabolism and growth. PMID:24563655

Banks, H.T.; Rehm, K.L.

2013-01-01

81

Collimator design for experimental minibeam radiation therapy  

SciTech Connect

Purpose: To design and optimize a minibeam collimator for minibeam radiation therapy studies using a 250 kVp x-ray machine as a simulated synchrotron source. Methods: A Philips RT250 orthovoltage x-ray machine was modeled using the EGSnrc/BEAMnrc Monte Carlo software. The resulting machine model was coupled to a model of a minibeam collimator with a beam aperture of 1 mm. Interaperture spacing and collimator thickness were varied to produce a minibeam with the desired peak-to-valley ratio. Results: Proper design of a minibeam collimator with Monte Carlo methods requires detailed knowledge of the x-ray source setup. For a cathode-ray tube source, the beam spot size, target angle, and source shielding all determine the final valley-to-peak dose ratio. Conclusions: A minibeam collimator setup was created, which can deliver a 30 Gy peak dose minibeam radiation therapy treatment at depths less than 1 cm with a valley-to-peak dose ratio on the order of 23%.

Babcock, Kerry; Sidhu, Narinder; Kundapur, Vijayananda; Ali, Kaiser [Saskatoon Cancer Centre, 20 Campus Drive, Saskatoon, Saskatchewan S7N 4H4 (Canada)

2011-04-15

82

Experimental design for study of nucleate boiling in porous structures  

E-print Network

The superheat required to initiate nucleate boiling inside porous wicks is not well understood in practice. This thesis reports the design of an experimental setup for investigating the onset of vapor nucleation in sintered ...

Kelley, Mitchell Joseph

2011-01-01

83

Experimental Design and Inferential Modeling in Pharmaceutical Crystallization  

E-print Network

. Braatz. 160 January 2001 et al., 19991, the ratio of the nucleated crystal mass to seed crystal massExperimental Design and Inferential Modeling in Pharmaceutical Crystallization Timokleia seed type, seed amount, temperature, solvent ratio, addition time, and agitation intensity

Braatz, Richard D.

84

A Bayesian experimental design approach to structural health monitoring  

SciTech Connect

Optimal system design for SHM involves two primarily challenges. The first is the derivation of a proper performance function for a given system design. The second is the development of an efficient optimization algorithm for choosing a design that maximizes, or nearly maximizes the performance function. In this paper we will outline how an SHM practitioner can construct the proper performance function by casting the entire design problem into a framework of Bayesian experimental design. The approach demonstrates how the design problem necessarily ties together all steps of the SHM process.

Farrar, Charles [Los Alamos National Laboratory; Flynn, Eric [UCSD; Todd, Michael [UCSD

2010-01-01

85

Sex differences in children's speech arising from the experimental design  

E-print Network

SEX DIFFERENCES IN CHILDREN'S SPEECH ARISING FROM THE EXPERIMENTAL DESIGN A Thesis CONNIE JO WALTERS Submitted to the Graduate College of Texas ARM University in Partial fulfillment of the requirement for the degree of MASTER OF SCIENCE... August 1979 Major Subject: Psychology SEX DIFFERENCES IN CHILDREN'S SPEECH ARISING FROM THE EXPERIMENTAL DESIGN A Thesis by CONNIE JO WALTERS Approved as to style and content by, (Chairman of Committee) (Member) (Member) (Membe (Head...

Walters, Connie Jo

2012-06-07

86

Optimal experimental design for placement of boreholes  

NASA Astrophysics Data System (ADS)

Drilling for deep resources is an expensive endeavor. Among the many problems finding the optimal drilling location for boreholes is one of the challenging questions. We contribute to this discussion by using a simulation based assessment of possible future borehole locations. We study the problem of finding a new borehole location in a given geothermal reservoir in terms of a numerical optimization problem. In a geothermal reservoir the temporal and spatial distribution of temperature and hydraulic pressure may be simulated using the coupled differential equations for heat transport and mass and momentum conservation for Darcy flow. Within this model the permeability and thermal conductivity are dependent on the geological layers present in the subsurface model of the reservoir. In general, those values involve some uncertainty making it difficult to predict actual heat source in the ground. Within optimal experimental the question is which location and to which depth to drill the borehole in order to estimate conductivity and permeability with minimal uncertainty. We introduce a measure for computing the uncertainty based on simulations of the coupled differential equations. The measure is based on the Fisher information matrix of temperature data obtained through the simulations. We assume that the temperature data is available within the full borehole. A minimization of the measure representing the uncertainty in the unknown permeability and conductivity parameters is performed to determine the optimal borehole location. We present the theoretical framework as well as numerical results for several 2d subsurface models including up to six geological layers. Also, the effect of unknown layers on the introduced measure is studied. Finally, to obtain a more realistic estimate of optimal borehole locations, we couple the optimization to a cost model for deep drilling problems.

Padalkina, Kateryna; Bücker, H. Martin; Seidler, Ralf; Rath, Volker; Marquart, Gabriele; Niederau, Jan; Herty, Michael

2014-05-01

87

Comparison of the tool life of tungsten carbides coated by multi-layer TiCN and TiAlCN for end mills using the Taguchi method  

Microsoft Academic Search

The purpose of the experiments reported in this paper is to use the Taguchi methods to investigate the wear of TiCN\\/TiAlCN coated onto various tool materials under various cutting conditions in the milling of quenched AISI 1045 carbon steel. The experimental results demonstrate that the tool material is the major parameter among the four controllable factors (different coated deposition, feed

Tsao Chung-Chen; Hocheng Hong

2002-01-01

88

Analysis of spinal lumbar interbody fusion cage subsidence using Taguchi method, finite element analysis, and artificial neural network  

NASA Astrophysics Data System (ADS)

Subsidence, when implant penetration induces failure of the vertebral body, occurs commonly after spinal reconstruction. Anterior lumbar interbody fusion (ALIF) cages may subside into the vertebral body and lead to kyphotic deformity. No previous studies have utilized an artificial neural network (ANN) for the design of a spinal interbody fusion cage. In this study, the neural network was applied after initiation from a Taguchi L 18 orthogonal design array. Three-dimensional finite element analysis (FEA) was performed to address the resistance to subsidence based on the design changes of the material and cage contact region, including design of the ridges and size of the graft area. The calculated subsidence is derived from the ANN objective function which is defined as the resulting maximum von Mises stress (VMS) on the surface of a simulated bone body after axial compressive loading. The ANN was found to have minimized the bone surface VMS, thereby optimizing the ALIF cage given the design space. Therefore, the Taguchi-FEA-ANN approach can serve as an effective procedure for designing a spinal fusion cage and improving the biomechanical properties.

Nassau, Christopher John; Litofsky, N. Scott; Lin, Yuyi

2012-09-01

89

FACTORIAL EXPERIMENTAL DESIGN APPLIED TO THE IMMUNOLOGICAL STUDY OF TWO  

E-print Network

FACTORIAL EXPERIMENTAL DESIGN APPLIED TO THE IMMUNOLOGICAL STUDY OF TWO FOOT-AND-MOUTH DISEASE design could be applied to the immunological stidy of 2 strains of foot-and-mouth disease virus, and we significant interaction. - Analysis of the simple effects. - Establishment of immunological rela- tions

Boyer, Edmond

90

Randomizing Roaches: Exploring the "Bugs" of Randomization in Experimental Design  

ERIC Educational Resources Information Center

Understanding the roles of random selection and random assignment in experimental design is a central learning objective in most introductory statistics courses. This article describes an activity, appropriate for a high school or introductory statistics course, designed to teach the concepts, values and pitfalls of random selection and assignment…

Wagler, Amy; Wagler, Ron

2014-01-01

91

Optimization of process parameters for ultrasonic drilling of advanced engineering ceramics using the Taguchi approach  

Microsoft Academic Search

The effect of process parameters on the cutting ratio (ratio of material removal rate to tool wear rate) for ultrasonic drilling of alumina-based ceramics using silicon carbide abrasive was studied. The parameters considered were workpiece material, tool material, grit size of the abrasive, power rating, and slurry concentration. Taguchi’s optimization approach was used to obtain the optimal parameters. The significant

R. S. Jadoun; Pradeep Kumar; B. K. Mishra; R. C. S. Mehta

2006-01-01

92

Design of an experimental set up for convective drying: experimental studies at different drying temperature  

NASA Astrophysics Data System (ADS)

An experimental setup is designed to investigate the convective drying of moist object experimentally. All the design data, components of setup, materials and specifications are presented. Transient moisture content of a rectangular shaped potato slice (4 × 2 × 2 cm) is measured at different air temperatures of 40, 50, 60 and 70 °C with an air velocity of 2 m/s. Two different drying rate periods are observed. Results are compared with available results from literature.

Mohan, V. P. Chandra; Talukdar, Prabal

2013-01-01

93

Study of Titanium Alloy Sheet During H-sectioned Rolling Forming Using the Taguchi Method  

NASA Astrophysics Data System (ADS)

This study employs commercial DEFORM™ three-dimensional finite element code to investigate the plastic deformation behavior of Ti-6Al-4V titanium alloy sheet during the H-sectioned rolling process. The simulations are based on a rigid-plastic model and assume that the upper and lower rolls are rigid bodies and that the temperature rise induced during rolling is sufficiently small that it can be ignored. The effects of the roll profile, the friction factor between the rolls and the titanium alloy, the rolling temperature and the roll radii on the rolling force, the roll torque and the effective strain induced in the rolled product are examined. The Taguchi method is employed to optimize the H-sectioned rolling process parameters. The results confirm the effectiveness of this robust design methodology in optimizing the H-sectioned rolling process parameters for the current Ti-6Al-4V titanium alloy.

Chen, Dyi-Cheng; Gu, Wun-Syuan; Hwang, Yeong-Maw

2007-05-01

94

Experimental Methodology in English Teaching and Learning: Method Features, Validity Issues, and Embedded Experimental Design  

ERIC Educational Resources Information Center

Experimental methods have played a significant role in the growth of English teaching and learning studies. The paper presented here outlines basic features of experimental design, including the manipulation of independent variables, the role and practicality of randomised controlled trials (RCTs) in educational research, and alternative methods…

Lee, Jang Ho

2012-01-01

95

Inductive logic: from data analysis to experimental design  

NASA Astrophysics Data System (ADS)

In celebration of the work of Richard Threlkeld Cox, we explore inductive logic and its role in science touching on both experimental design and analysis of experimental results. In this exploration we demonstrate that the duality between the logic of assertions and the logic of questions has important consequences. We discuss the conjecture that the relevance or bearing, b, of a question on an issue can be expressed in terms of the probabilities, p, of the assertions that answer the question via the entropy. In its application to the scientific method, the logic of questions, inductive inquiry, can be applied to design an experiment that most effectively addresses a scientific issue. This is performed by maximizing the relevance of the experimental question to the scientific issue to be resolved. It is shown that these results are related to the mutual information between the experiment and the scientific issue, and that experimental design is akin to designing a communication channel that most efficiently communicates information relevant to the scientific issue to the experimenter. Application of the logic of assertions, inductive inference (Bayesian inference) completes the experimental process by allowing the researcher to make inferences based on the information obtained from the experiment.

Knuth, Kevin H.

2002-05-01

96

Design and Experimental Study on Spinning Solid Rocket Motor  

NASA Astrophysics Data System (ADS)

The study on spinning solid rocket motor (SRM) which used as power plant of twice throwing structure of aerial submunition was introduced. This kind of SRM which with the structure of tangential multi-nozzle consists of a combustion chamber, propellant charge, 4 tangential nozzles, ignition device, etc. Grain design, structure design and prediction of interior ballistic performance were described, and problem which need mainly considered in design were analyzed comprehensively. Finally, in order to research working performance of the SRM, measure pressure-time curve and its speed, static test and dynamic test were conducted respectively. And then calculated values and experimental data were compared and analyzed. The results indicate that the designed motor operates normally, and the stable performance of interior ballistic meet demands. And experimental results have the guidance meaning for the pre-research design of SRM.

Xue, Heng; Jiang, Chunlan; Wang, Zaicheng

97

Microelectronics package design using experimentally-validated modeling and simulation.  

SciTech Connect

Packaging high power radio frequency integrated circuits (RFICs) in low temperature cofired ceramic (LTCC) presents many challenges. Within the constraints of LTCC fabrication, the design must provide the usual electrical isolation and interconnections required to package the IC, with additional consideration given to RF isolation and thermal management. While iterative design and prototyping is an option for developing RFIC packaging, it would be expensive and most likely unsuccessful due to the complexity of the problem. To facilitate and optimize package design, thermal and mechanical simulations were used to understand and control the critical parameters in LTCC package design. The models were validated through comparisons to experimental results. This paper summarizes an experimentally-validated modeling approach to RFIC package design, and presents some results and key findings.

Johnson, Jay Dean; Young, Nathan Paul; Ewsuk, Kevin Gregory

2010-11-01

98

Characterizing the Experimental Procedure in Science Laboratories: A Preliminary Step towards Students Experimental Design  

ERIC Educational Resources Information Center

Many studies have stressed students' lack of understanding of experiments in laboratories. Some researchers suggest that if students design all or parts of entire experiment, as part of an inquiry-based approach, it would overcome certain difficulties. It requires that a procedure be written for experimental design. The aim of this paper is to…

Girault, Isabelle; d'Ham, Cedric; Ney, Muriel; Sanchez, Eric; Wajeman, Claire

2012-01-01

99

A comparison of controller designs for an experimental flexible structure  

NASA Technical Reports Server (NTRS)

Control systems design and hardware testing are addressed for an experimental structure that displays the characteristics of a typical flexible spacecraft. The results of designing and implementing various control design methodologies are described. The design methodologies under investigation include linear quadratic Gaussian control, static and dynamic dissipative controls, and H-infinity optimal control. Among the three controllers considered, it is shown, through computer simulation and laboratory experiments on the evolutionary structure, that the dynamic dissipative controller gave the best results in terms of vibration suppression and robustness with respect to modeling errors.

Lim, K. B.; Maghami, P. G.; Joshi, S. M.

1991-01-01

100

14 CFR 437.85 - Allowable design changes; modification of an experimental permit.  

Code of Federal Regulations, 2010 CFR

...Allowable design changes; modification of an experimental permit. 437.85 Section...EXPERIMENTAL PERMITS Terms and Conditions of an Experimental Permit § 437.85 Allowable design changes; modification of an experimental permit. (a) The...

2010-01-01

101

14 CFR 437.85 - Allowable design changes; modification of an experimental permit.  

...Allowable design changes; modification of an experimental permit. 437.85 Section...EXPERIMENTAL PERMITS Terms and Conditions of an Experimental Permit § 437.85 Allowable design changes; modification of an experimental permit. (a) The...

2014-01-01

102

14 CFR 437.85 - Allowable design changes; modification of an experimental permit.  

Code of Federal Regulations, 2013 CFR

...Allowable design changes; modification of an experimental permit. 437.85 Section...EXPERIMENTAL PERMITS Terms and Conditions of an Experimental Permit § 437.85 Allowable design changes; modification of an experimental permit. (a) The...

2013-01-01

103

14 CFR 437.85 - Allowable design changes; modification of an experimental permit.  

Code of Federal Regulations, 2012 CFR

...Allowable design changes; modification of an experimental permit. 437.85 Section...EXPERIMENTAL PERMITS Terms and Conditions of an Experimental Permit § 437.85 Allowable design changes; modification of an experimental permit. (a) The...

2012-01-01

104

14 CFR 437.85 - Allowable design changes; modification of an experimental permit.  

Code of Federal Regulations, 2011 CFR

...Allowable design changes; modification of an experimental permit. 437.85 Section...EXPERIMENTAL PERMITS Terms and Conditions of an Experimental Permit § 437.85 Allowable design changes; modification of an experimental permit. (a) The...

2011-01-01

105

Long Run Behavior of Bayesian Methods; Bayesian Experimental Design  

E-print Network

% of the time that we reach a conclusion in the Monte Carlo experiment. p.9/38 #12;Robustness to model prior, but only if the probability exceeds Pcrit. Iterate via Monte Carlo: · 1.Choose a model by sampling fromMiscellany : Long Run Behavior of Bayesian Methods; Bayesian Experimental Design (Lecture 4) Tom

Loredo, Thomas J.

106

Bands to Books: Connecting Literature to Experimental Design  

ERIC Educational Resources Information Center

This article describes an interdisciplinary unit of study on the inquiry process and experimental design that seamlessly integrates math, science, and reading using a rubber band cannon. This unit was conducted over an eight-day period in two sixth-grade classes (one math and one science with each class consisting of approximately 27 students and…

Bintz, William P.; Moore, Sara Delano

2004-01-01

107

Serving Embedded Content via Web Applications: Model, Design and Experimentation  

E-print Network

Serving Embedded Content via Web Applications: Model, Design and Experimentation Simon Duquennoy dedicated terminals. A new trend consists in embedding Web servers in small devices, making both access of embedded Web servers, and we introduce a taxonomy of the contents possi- bly served by Web applications

Paris-Sud XI, Université de

108

Design, Control, and Experimental Performance of a Teleoperated Robotic Fish  

E-print Network

Design, Control, and Experimental Performance of a Teleoperated Robotic Fish Evangelos Papadopoulos National Technical University of Athens 15780 Athens, Greece egpapado@central.ntua.gr Abstract-- Fish-cost teleoperated underwater robotic fish, driven by an oscillating foil. The main principles for the development

Papadopoulos, Evangelos

109

Using Propensity Score Methods to Approximate Factorial Experimental Designs  

ERIC Educational Resources Information Center

The purpose of this study is through Monte Carlo simulation to compare several propensity score methods in approximating factorial experimental design and identify best approaches in reducing bias and mean square error of parameter estimates of the main and interaction effects of two factors. Previous studies focused more on unbiased estimates of…

Dong, Nianbo

2011-01-01

110

Single-Subject Experimental Design for Evidence-Based Practice  

ERIC Educational Resources Information Center

Purpose: Single-subject experimental designs (SSEDs) represent an important tool in the development and implementation of evidence-based practice in communication sciences and disorders. The purpose of this article is to review the strategies and tactics of SSEDs and their application in speech-language pathology research. Method: The authors…

Byiers, Breanne J.; Reichle, Joe; Symons, Frank J.

2012-01-01

111

Design and Experimental Characterization of a Multifrequency Flexural Ultrasonic Actuator  

Microsoft Academic Search

In this work, a multifrequency flexural ultrasonic actuator is proposed, designed, and experimentally characterized. The actuator is composed of a Langevin transducer and of a displacement amplifier. The displacement amplifier is able to transform the almost flat axial displacement provided by the Langevin transducer at its back end into a flexural deformation that produces the maximum axial displacement at the

Actuator antonio Iula

2009-01-01

112

Experimental Design for Comparing Static Concurrency Analysis Techniques  

E-print Network

Experimental Design for Comparing Static Concurrency Analysis Techniques A.T. Chamillard Lori A that seems well suited to empirical investigation, comparing the performance of several static analysis tools to understand than sequential ones. Thus, it is imperative that cost-effective techniques be developed

Massachusetts at Amherst, University of

113

Some key things industrial engineers should know about experimental design  

Microsoft Academic Search

Experiments are fundamental to enhancing understanding of the complex industrial processes which we deal with every day. Experimental Design (ED) is a very powerful tool that assists engineers and scientist to discover a set of variables which are most important for a process and thereby provide a great insight into the way a process or system works. It is superior

Jiju Antony

1998-01-01

114

Design of a miniature wideband radar experimental system  

Microsoft Academic Search

Wideband radars have been found more important both in civil and military applications. Micromation is one key technology for radars mounted at missiles, unmanned aerial vehicles (UAV), satellites, etc. The scheme of a miniature wideband radar experimental system is introduced in this paper, while the design and implementation of a wideband signal generator is analyzed in detail. The radar is

Zhang Xiao-wei; Li Ming; Zuo Lei

2011-01-01

115

Experimental Design to Evaluate Directed Adaptive Mutation in Mammalian Cells  

PubMed Central

Background We describe the experimental design for a methodological approach to determine whether directed adaptive mutation occurs in mammalian cells. Identification of directed adaptive mutation would have profound practical significance for a wide variety of biomedical problems, including disease development and resistance to treatment. In adaptive mutation, the genetic or epigenetic change is not random; instead, the presence and type of selection influences the frequency and character of the mutation event. Adaptive mutation can contribute to the evolution of microbial pathogenesis, cancer, and drug resistance, and may become a focus of novel therapeutic interventions. Objective Our experimental approach was designed to distinguish between 3 types of mutation: (1) random mutations that are independent of selective pressure, (2) undirected adaptive mutations that arise when selective pressure induces a general increase in the mutation rate, and (3) directed adaptive mutations that arise when selective pressure induces targeted mutations that specifically influence the adaptive response. The purpose of this report is to introduce an experimental design and describe limited pilot experiment data (not to describe a complete set of experiments); hence, it is an early report. Methods An experimental design based on immortalization of mouse embryonic fibroblast cells is presented that links clonal cell growth to reversal of an inactivating polyadenylation site mutation. Thus, cells exhibit growth only in the presence of both the countermutation and an inducing agent (doxycycline). The type and frequency of mutation in the presence or absence of doxycycline will be evaluated. Additional experimental approaches would determine whether the cells exhibit a generalized increase in mutation rate and/or whether the cells show altered expression of error-prone DNA polymerases or of mismatch repair proteins. Results We performed the initial stages of characterizing our system and have limited preliminary data from several pilot experiments. Cell growth and DNA sequence data indicate that we have identified a cell clone that exhibits several suitable characteristics, although further study is required to identify a more optimal cell clone. Conclusions The experimental approach is based on a quantum biological model of basis-dependent selection describing a novel mechanism of adaptive mutation. This project is currently inactive due to lack of funding. However, consistent with the objective of early reports, we describe a proposed study that has not produced publishable results, but is worthy of report because of the hypothesis, experimental design, and protocols. We outline the project’s rationale and experimental design, with its strengths and weaknesses, to stimulate discussion and analysis, and lay the foundation for future studies in this field. PMID:25491410

Chiaro, Christopher R; May, Tobias

2014-01-01

116

Experimental Study on Abrasive Waterjet Polishing of Hydraulic Turbine Blades  

NASA Astrophysics Data System (ADS)

In this paper, an experimental investigation is implemented on the abrasive waterjet polishing technique to evaluate its capability in polishing of surfaces and edges of hydraulic turbine blades. For this, the properties of this method are studied and the main parameters affecting its performance are determined. Then, an experimental test-rig is designed, manufactured and tested to be used in this study. This test-rig can be used to polish linear and planar areas on the surface of the desired workpieces. Considering the number of parameters and their levels, the Taguchi method is used to design the preliminary experiments. All experiments are then implemented according to the Taguchi L18 orthogonal array. The signal-to-noise ratios obtained from the results of these experiments are used to determine the importance of the controlled polishing parameters on the final quality of the polished surface. The evaluations on these ratios reveal that the nozzle angle and the nozzle diameter have the most important impact on the results. The outcomes of these experiments can be used as a basis to design a more precise set of experiments in which the optimal values of each parameter can be estimated.

Khakpour, H.; Birglenl, L.; Tahan, A.; Paquet, F.

2014-12-01

117

Preliminary structural design of a lunar transfer vehicle aerobrake. M.S. Thesis  

NASA Technical Reports Server (NTRS)

An aerobrake concept for a Lunar transfer vehicle was weight optimized through the use of the Taguchi design method, structural finite element analyses and structural sizing routines. Six design parameters were chosen to represent the aerobrake structural configuration. The design parameters included honeycomb core thickness, diameter to depth ratio, shape, material, number of concentric ring frames, and number of radial frames. Each parameter was assigned three levels. The minimum weight aerobrake configuration resulting from the study was approx. half the weight of the average of all twenty seven experimental configurations. The parameters having the most significant impact on the aerobrake structural weight were identified.

Bush, Lance B.

1992-01-01

118

Quiet Clean Short-Haul Experimental Engine (QCSEE). Preliminary analyses and design report, volume 2  

NASA Technical Reports Server (NTRS)

The experimental and flight propulsion systems are presented. The following areas are discussed: engine core and low pressure turbine design; bearings and seals design; controls and accessories design; nacelle aerodynamic design; nacelle mechanical design; weight; and aircraft systems design.

1974-01-01

119

Design and Implementation of an Experimental Segway Model  

NASA Astrophysics Data System (ADS)

The segway is the first transportation product to stand, balance, and move in the same way we do. It is a truly 21st-century idea. The aim of this research is to study the theory behind building segway vehicles based on the stabilization of an inverted pendulum. An experimental model has been designed and implemented through this study. The model has been tested for its balance by running a Proportional Derivative (PD) algorithm on a microprocessor chip. The model has been identified in order to serve as an educational experimental platform for segways.

Younis, Wael; Abdelati, Mohammed

2009-03-01

120

Design and experimental results for the S809 airfoil  

SciTech Connect

A 21-percent-thick, laminar-flow airfoil, the S809, for horizontal-axis wind-turbine applications, has been designed and analyzed theoretically and verified experimentally in the low-turbulence wind tunnel of the Delft University of Technology Low Speed Laboratory, The Netherlands. The two primary objectives of restrained maximum lift, insensitive to roughness, and low profile drag have been achieved. The airfoil also exhibits a docile stall. Comparisons of the theoretical and experimental results show good agreement. Comparisons with other airfoils illustrate the restrained maximum lift coefficient as well as the lower profile-drag coefficients, thus confirming the achievement of the primary objectives.

Somers, D.M. [Airfoils, Inc., State College, PA (United States)] [Airfoils, Inc., State College, PA (United States)

1997-01-01

121

Optimal active vibration absorber - Design and experimental results  

NASA Technical Reports Server (NTRS)

An optimal active vibration absorber can provide guaranteed closed-loop stability and control for large flexible space structures with collocated sensors/actuators. The active vibration absorber is a second-order dynamic system which is designed to suppress any unwanted structural vibration. This can be designed with minimum knowledge of the controlled system. Two methods for optimizing the active vibration absorber parameters are illustrated: minimum resonant amplitude and frequency matched active controllers. The Controls-Structures Interaction Phase-1 Evolutionary Model at NASA LaRC is used to demonstrate the effectiveness of the active vibration absorber for vibration suppression. Performance is compared numerically and experimentally using acceleration feedback.

Lee-Glauser, Gina; Juang, Jer-Nan; Sulla, Jeffrey L.

1993-01-01

122

Optimal active vibration absorber: Design and experimental results  

NASA Technical Reports Server (NTRS)

An optimal active vibration absorber can provide guaranteed closed-loop stability and control for large flexible space structures with collocated sensors/actuators. The active vibration absorber is a second-order dynamic system which is designed to suppress any unwanted structural vibration. This can be designed with minimum knowledge of the controlled system. Two methods for optimizing the active vibration absorber parameters are illustrated: minimum resonant amplitude and frequency matched active controllers. The Controls-Structures Interaction Phase-1 Evolutionary Model at NASA LaRC is used to demonstrate the effectiveness of the active vibration absorber for vibration suppression. Performance is compared numerically and experimentally using acceleration feedback.

Lee-Glauser, Gina; Juang, Jer-Nan; Sulla, Jeffrey L.

1992-01-01

123

TIBER: Tokamak Ignition/Burn Experimental Research. Final design report  

SciTech Connect

The Tokamak Ignition/Burn Experimental Research (TIBER) device is the smallest superconductivity tokamak designed to date. In the design plasma shaping is used to achieve a high plasma beta. Neutron shielding is minimized to achieve the desired small device size, but the superconducting magnets must be shielded sufficiently to reduce the neutron heat load and the gamma-ray dose to various components of the device. Specifications of the plasma-shaping coil, the shielding, coaling, requirements, and heating modes are given. 61 refs., 92 figs., 30 tabs. (WRF)

Henning, C.D.; Logan, B.G.; Barr, W.L.; Bulmer, R.H.; Doggett, J.N.; Johnson, B.M.; Lee, J.D.; Hoard, R.W.; Miller, J.R.; Slack, D.S.

1985-11-01

124

Design and Experimental Evaluation of a Magnetorheological Brake  

Microsoft Academic Search

A new magnetorheological (MR) brake prototype was designed, fabricated and tested. Firstly, the rheological properties of\\u000a MR fluids, in particular the dynamic yield stress, were experimentally investigated based on a Bingham plastic model. The\\u000a working principles of the MR brake were then analysed and discussed. The equations for transmitted torque were derived and\\u000a used to evaluate the disc-shaped MR brake.

W. H. Li; H. Du

2003-01-01

125

Bands to Books: Connecting Literature to Experimental Design  

NSDL National Science Digital Library

This interdisciplinary unit of study on the inquiry process and experimental design that seamlessly integrates math, science, and reading using a rubber band cannon. The authors begin by describing a series of interrelated curricular engagements that make up the unit. Throughout, they share samples of student work. Lastly, they describe some lessons learned and discuss both problems and pleasures of creating and implementing an interdisciplinary curriculum at the middle level.

Moore, Sara D.; Bintz, William P.

2004-11-01

126

Optimization of FS Welding Parameters for Improving Mechanical Behavior of AA2024-T351 Joints Based on Taguchi Method  

NASA Astrophysics Data System (ADS)

In the present study, the design of an experiment technique, the Taguchi method, has been used to optimize the friction stir welding (FSW) parameters for improving mechanical behavior of AA2024-T351 joints. The parameters considered were vertical downward forging force, tool travel speed, and probe length. An orthogonal array of L9 (34) was used; ANOVA analyses were carried out to identify the significant factors affecting tensile strength (Global Efficiency to Tensile Strength—GETS), bending strength (Global Efficiency to Bending—GEB), and hardness field. The percentage contribution of each parameter was also determined. As a result of the Taguchi analysis in this study, the probe length is the most significant parameter on GETS, and the tool travel speed is the most important parameter affecting both the GEB and the hardness field. An algebraic model for predicting the best mechanical performance, namely fatigue resistance, was developed and the optimal FSW combination was determined using this model. The results obtained were validated by conducting confirmation tests, the results of which verify the adequacy and effectiveness of this approach.

Vidal, C.; Infante, V.

2013-08-01

127

Development of a cell formation heuristic by considering realistic data using principal component analysis and Taguchi's method  

NASA Astrophysics Data System (ADS)

Over the last four decades of research, numerous cell formation algorithms have been developed and tested, still this research remains of interest to this day. Appropriate manufacturing cells formation is the first step in designing a cellular manufacturing system. In cellular manufacturing, consideration to manufacturing flexibility and production-related data is vital for cell formation. The consideration to this realistic data makes cell formation problem very complex and tedious. It leads to the invention and implementation of highly advanced and complex cell formation methods. In this paper an effort has been made to develop a simple and easy to understand/implement manufacturing cell formation heuristic procedure with considerations to the number of production and manufacturing flexibility-related parameters. The heuristic minimizes inter-cellular movement cost/time. Further, the proposed heuristic is modified for the application of principal component analysis and Taguchi's method. Numerical example is explained to illustrate the approach. A refinement in the results is observed with adoption of principal component analysis and Taguchi's method.

Kumar, Shailendra; Sharma, Rajiv Kumar

2014-12-01

128

Development of the Biological Experimental Design Concept Inventory (BEDCI)  

PubMed Central

Interest in student conception of experimentation inspired the development of a fully validated 14-question inventory on experimental design in biology (BEDCI) by following established best practices in concept inventory (CI) design. This CI can be used to diagnose specific examples of non–expert-like thinking in students and to evaluate the success of teaching strategies that target conceptual changes. We used BEDCI to diagnose non–expert-like student thinking in experimental design at the pre- and posttest stage in five courses (total n = 580 students) at a large research university in western Canada. Calculated difficulty and discrimination metrics indicated that BEDCI questions are able to effectively capture learning changes at the undergraduate level. A high correlation (r = 0.84) between responses by students in similar courses and at the same stage of their academic career, also suggests that the test is reliable. Students showed significant positive learning changes by the posttest stage, but some non–expert-like responses were widespread and persistent. BEDCI is a reliable and valid diagnostic tool that can be used in a variety of life sciences disciplines. PMID:25185236

Deane, Thomas; Jeffery, Erica; Pollock, Carol; Birol, Gülnur

2014-01-01

129

Experimental designs for a Benign Paroxysmal Positional Vertigo model  

PubMed Central

Background The pathology of the Benign Paroxysmal Positional Vertigo (BPPV) is detected by a clinician through maneuvers consisting of a series of consecutive head turns that trigger the symptoms of vertigo in patient. A statistical model based on a new maneuver has been developed in order to calculate the volume of endolymph displaced after the maneuver. Methods A simplification of the Navier?Stokes problem from the fluids theory has been used to construct the model. In addition, the same cubic splines that are commonly used in kinematic control of robots were used to obtain an appropriate description of the different maneuvers. Then experimental designs were computed to obtain an optimal estimate of the model. Results D?optimal and c?optimal designs of experiments have been calculated. These experiments consist of a series of specific head turns of duration ?t and angle ? that should be performed by the clinician on the patient. The experimental designs obtained indicate the duration and angle of the maneuver to be performed as well as the corresponding proportion of replicates. Thus, in the D?optimal design for 100 experiments, the maneuver consisting of a positive 30° pitch from the upright position, followed by a positive 30° roll, both with a duration of one and a half seconds is repeated 47 times. Then the maneuver with 60° /6° pitch/roll during half a second is repeated 16 times and the maneuver 90° /90° pitch/roll during half a second is repeated 37 times. Other designs with significant differences are computed and compared. Conclusions A biomechanical model was derived to provide a quantitative basis for the detection of BPPV. The robustness study for the D?optimal design, with respect to the choice of the nominal values of the parameters, shows high efficiencies for small variations and provides a guide to the researcher. Furthermore, c?optimal designs give valuable assistance to check how efficient the D?optimal design is for the estimation of each of the parameters. The experimental designs provided in this paper allow the physician to validate the model. The authors of the paper have held consultations with an ENT consultant in order to align the outline more closely to practical scenarios. PMID:23509996

2013-01-01

130

Taguchi analysis of delamination associated with various drill bits in drilling of composite material  

Microsoft Academic Search

This paper presents a prediction and evaluation of delamination factor in use of twist drill, candle stick drill and saw drill. The approach is based on Taguchi’s method and the analysis of variance (ANOVA). An ultrasonic C-Scan to examine the delamination of carbon fiber-reinforced plastic (CFRP) laminate is used in this paper. The experiments were conducted to study the delamination

C. C Tsao; H Hocheng

2004-01-01

131

Design and experimental validation of looped-tube thermoacoustic engine  

NASA Astrophysics Data System (ADS)

The aim of this paper is to present the design and experimental validation process for a thermoacoustic looped-tube engine. The design procedure consists of numerical modelling of the system using DELTA EC tool, Design Environment for Low-amplitude ThermoAcoustic Energy Conversion, in particular the effects of mean pressure and regenerator configuration on the pressure amplitude and acoustic power generated. This is followed by the construction of a practical engine system equipped with a ceramic regenerator — a substrate used in automotive catalytic converters with fine square channels. The preliminary testing results are obtained and compared with the simulations in detail. The measurement results agree very well on the qualitative level and are reasonably close in the quantitative sense.

Abduljalil, Abdulrahman S.; Yu, Zhibin; Jaworski, Artur J.

2011-10-01

132

Single-Subject Experimental Design for Evidence-Based Practice  

PubMed Central

Purpose Single-subject experimental designs (SSEDs) represent an important tool in the development and implementation of evidence-based practice in communication sciences and disorders. The purpose of this article is to review the strategies and tactics of SSEDs and their application in speech-language pathology research. Method The authors discuss the requirements of each design, followed by advantages and disadvantages. The logic and methods for evaluating effects in SSED are reviewed as well as contemporary issues regarding data analysis with SSED data sets. Examples of challenges in executing SSEDs are included. Specific exemplars of how SSEDs have been used in speech-language pathology research are provided throughout. Conclusion SSED studies provide a flexible alternative to traditional group designs in the development and identification of evidence-based practice in the field of communication sciences and disorders. PMID:23071200

Byiers, Breanne J.; Reichle, Joe; Symons, Frank J.

2014-01-01

133

A Hierarchical Adaptive Approach to Optimal Experimental Design  

PubMed Central

Experimentation is at the core of research in the behavioral and neural sciences, yet observations can be expensive and time-consuming to acquire (e.g., MRI scans, responses from infant participants). A major interest of researchers is designing experiments that lead to maximal accumulation of information about the phenomenon under study with the fewest possible number of observations. In addressing this challenge, statisticians have developed adaptive design optimization methods. This letter introduces a hierarchical Bayes extension of adaptive design optimization that provides a judicious way to exploit two complementary schemes of inference (with past and future data) to achieve even greater accuracy and efficiency in information gain. We demonstrate the method in a simulation experiment in the field of visual perception. PMID:25149697

Kim, Woojae; Pitt, Mark A.; Lu, Zhong-Lin; Steyvers, Mark; Myung, Jay I.

2014-01-01

134

Constrained Response Surface Optimisation and Taguchi Methods for Precisely Atomising Spraying Process  

NASA Astrophysics Data System (ADS)

This research presents a development of a design of experiment technique for quality improvement in automotive manufacturing industrial. The quality of interest is the colour shade, one of the key feature and exterior appearance for the vehicles. With low percentage of first time quality, the manufacturer has spent a lot of cost for repaired works as well as the longer production time. To permanently dissolve such problem, the precisely spraying condition should be optimized. Therefore, this work will apply the full factorial design, the multiple regression, the constrained response surface optimization methods or CRSOM, and Taguchi's method to investigate the significant factors and to determine the optimum factor level in order to improve the quality of paint shop. Firstly, 2? full factorial was employed to study the effect of five factors including the paint flow rate at robot setting, the paint levelling agent, the paint pigment, the additive slow solvent, and non volatile solid at spraying of atomizing spraying machine. The response values of colour shade at 15 and 45 degrees were measured using spectrophotometer. Then the regression models of colour shade at both degrees were developed from the significant factors affecting each response. Consequently, both regression models were placed into the form of linear programming to maximize the colour shade subjected to 3 main factors including the pigment, the additive solvent and the flow rate. Finally, Taguchi's method was applied to determine the proper level of key variable factors to achieve the mean value target of colour shade. The factor of non volatile solid was found to be one more additional factor at this stage. Consequently, the proper level of all factors from both experiment design methods were used to set a confirmation experiment. It was found that the colour shades, both visual at 15 and 45 angel of measurement degrees of spectrophotometer, were nearly closed to the target and the defective at quality gate was also reduced from 0.35 WDPV to 0.10 WDPV. This reveals that the objective of this research is met and this procedure can be used as quality improvement guidance for paint shop of automotive vehicle.

Luangpaiboon, P.; Suwankham, Y.; Homrossukon, S.

2010-10-01

135

Biosorption of malachite green from aqueous solutions by Pleurotus ostreatus using Taguchi method.  

PubMed

Dyes released into the environment have been posing a serious threat to natural ecosystems and aquatic life due to presence of heat, light, chemical and other exposures stable. In this study, the Pleurotus ostreatus (a macro-fungus) was used as a new biosorbent to study the biosorption of hazardous malachite green (MG) from aqueous solutions. The effective disposal of P. ostreatus is a meaningful work for environmental protection and maximum utilization of agricultural residues.The operational parameters such as biosorbent dose, pH, and ionic strength were investigated in a series of batch studies at 25°C. Freundlich isotherm model was described well for the biosorption equilibrium data. The biosorption process followed the pseudo-second-order kinetic model. Taguchi method was used to simplify the experimental number for determining the significance of factors and the optimum levels of experimental factors for MG biosorption. Biosorbent dose and initial MG concentration had significant influences on the percent removal and biosorption capacity. The highest percent removal reached 89.58% and the largest biosorption capacity reached 32.33 mg/g. The Fourier transform infrared spectroscopy (FTIR) showed that the functional groups such as, carboxyl, hydroxyl, amino and phosphonate groups on the biosorbent surface could be the potential adsorption sites for MG biosorption. P. ostreatus can be considered as an alternative biosorbent for the removal of dyes from aqueous solutions. PMID:24620852

Chen, Zhengsuo; Deng, Hongbo; Chen, Can; Yang, Ying; Xu, Heng

2014-01-01

136

Biosorption of malachite green from aqueous solutions by Pleurotus ostreatus using Taguchi method  

PubMed Central

Dyes released into the environment have been posing a serious threat to natural ecosystems and aquatic life due to presence of heat, light, chemical and other exposures stable. In this study, the Pleurotus ostreatus (a macro-fungus) was used as a new biosorbent to study the biosorption of hazardous malachite green (MG) from aqueous solutions. The effective disposal of P. ostreatus is a meaningful work for environmental protection and maximum utilization of agricultural residues. The operational parameters such as biosorbent dose, pH, and ionic strength were investigated in a series of batch studies at 25°C. Freundlich isotherm model was described well for the biosorption equilibrium data. The biosorption process followed the pseudo-second-order kinetic model. Taguchi method was used to simplify the experimental number for determining the significance of factors and the optimum levels of experimental factors for MG biosorption. Biosorbent dose and initial MG concentration had significant influences on the percent removal and biosorption capacity. The highest percent removal reached 89.58% and the largest biosorption capacity reached 32.33 mg/g. The Fourier transform infrared spectroscopy (FTIR) showed that the functional groups such as, carboxyl, hydroxyl, amino and phosphonate groups on the biosorbent surface could be the potential adsorption sites for MG biosorption. P. ostreatus can be considered as an alternative biosorbent for the removal of dyes from aqueous solutions. PMID:24620852

2014-01-01

137

Amplified energy harvester from footsteps: design, modeling, and experimental analysis  

NASA Astrophysics Data System (ADS)

This paper presents the design, modeling and experimental analysis of an amplified footstep energy harvester. With the unique design of amplified piezoelectric stack harvester the kinetic energy generated by footsteps can be effectively captured and converted into usable DC power that could potentially be used to power many electric devices, such as smart phones, sensors, monitoring cameras, etc. This doormat-like energy harvester can be used in crowded places such as train stations, malls, concerts, airport escalator/elevator/stairs entrances, or anywhere large group of people walk. The harvested energy provides an alternative renewable green power to replace power requirement from grids, which run on highly polluting and global-warming-inducing fossil fuels. In this paper, two modeling approaches are compared to calculate power output. The first method is derived from the single degree of freedom (SDOF) constitutive equations, and then a correction factor is applied onto the resulting electromechanically coupled equations of motion. The second approach is to derive the coupled equations of motion with Hamilton's principle and the constitutive equations, and then formulate it with the finite element method (FEM). Experimental testing results are presented to validate modeling approaches. Simulation results from both approaches agree very well with experimental results where percentage errors are 2.09% for FEM and 4.31% for SDOF.

Wang, Ya; Chen, Wusi; Guzman, Plinio; Zuo, Lei

2014-04-01

138

Acting like a physicist: Student approach study to experimental design  

NASA Astrophysics Data System (ADS)

National studies of science education have unanimously concluded that preparing our students for the demands of the 21st century workplace is one of the major goals. This paper describes a study of student activities in introductory college physics labs, which were designed to help students acquire abilities that are valuable in the workplace. In these labs [called Investigative Science Learning Environment (ISLE) labs], students design their own experiments. Our previous studies have shown that students in these labs acquire scientific abilities such as the ability to design an experiment to solve a problem, the ability to collect and analyze data, the ability to evaluate assumptions and uncertainties, and the ability to communicate. These studies mostly concentrated on analyzing students’ writing, evaluated by specially designed scientific ability rubrics. Recently, we started to study whether the ISLE labs make students not only write like scientists but also engage in discussions and act like scientists while doing the labs. For example, do students plan an experiment, validate assumptions, evaluate results, and revise the experiment if necessary? A brief report of some of our findings that came from monitoring students’ activity during ISLE and nondesign labs was presented in the Physics Education Research Conference Proceedings. We found differences in student behavior and discussions that indicated that ISLE labs do in fact encourage a scientistlike approach to experimental design and promote high-quality discussions. This paper presents a full description of the study.

Karelina, Anna; Etkina, Eugenia

2007-12-01

139

Acting like a physicist: Student approach study to experimental design  

NSDL National Science Digital Library

National studies of science education have unanimously concluded that preparing our students for the demands of the 21st century workplace is one of the major goals. This paper describes a study of student activities in introductory college physics labs, which were designed to help students acquire abilities that are valuable in the workplace. In these labs [called Investigative Science Learning Environment (ISLE) labs], students design their own experiments. Our previous studies have shown that students in these labs acquire scientific abilities such as the ability to design an experiment to solve a problem, the ability to collect and analyze data, the ability to evaluate assumptions and uncertainties, and the ability to communicate. These studies mostly concentrated on analyzing studentsâ writing, evaluated by specially designed scientific ability rubrics. Recently, we started to study whether the ISLE labs make students not only write like scientists but also engage in discussions and act like scientists while doing the labs. For example, do students plan an experiment, validate assumptions, evaluate results, and revise the experiment if necessary? A brief report of some of our findings that came from monitoring studentsâ activity during ISLE and nondesign labs was presented in the Physics Education Research Conference Proceedings. We found differences in student behavior and discussions that indicated that ISLE labs do in fact encourage a scientistlike approach to experimental design and promote high-quality discussions. This paper presents a full description of the study.

Karelina, Anna; Etkina, Eugenia

2008-09-24

140

Computational Design and Experimental Validation of New Thermal Barrier Systems  

SciTech Connect

This project (10/01/2010-9/30/2014), “Computational Design and Experimental Validation of New Thermal Barrier Systems”, originates from Louisiana State University (LSU) Mechanical Engineering Department and Southern University (SU) Department of Computer Science. This project will directly support the technical goals specified in DE-FOA-0000248, Topic Area 3: Turbine Materials, by addressing key technologies needed to enable the development of advanced turbines and turbine-based systems that will operate safely and efficiently using coal-derived synthesis gases. In this project, the focus is to develop and implement novel molecular dynamics method to improve the efficiency of simulation on novel TBC materials; perform high performance computing (HPC) on complex TBC structures to screen the most promising TBC compositions; perform material characterizations and oxidation/corrosion tests; and demonstrate our new thermal barrier coating (TBC) systems experimentally under integrated gasification combined cycle (IGCC) environments.

Guo, Shengmin; Yang, Shizhong; Khosravi, Ebrahim

2014-04-01

141

Design and experimental results for the S814 airfoil  

SciTech Connect

A 24-percent-thick airfoil, the S814, for the root region of a horizontal-axis wind-turbine blade has been designed and analyzed theoretically and verified experimentally in the low-turbulence wind tunnel of the Delft University of Technology Low Speed Laboratory, The Netherlands. The two primary objectives of high maximum lift, insensitive to roughness, and low profile drag have been achieved. The constraints on the pitching moment and the airfoil thickness have been satisfied. Comparisons of the theoretical and experimental results show good agreement with the exception of maximum lift which is overpredicted. Comparisons with other airfoils illustrate the higher maximum lift and the lower profile drag of the S814 airfoil, thus confirming the achievement of the objectives.

Somers, D.M. [Airfoils, Inc., State College, PA (United States)

1997-01-01

142

Optimization of formulation variables of benzocaine liposomes using experimental design.  

PubMed

This study aimed to optimize, by means of an experimental design multivariate strategy, a liposomal formulation for topical delivery of the local anaesthetic agent benzocaine. The formulation variables for the vesicle lipid phase uses potassium glycyrrhizinate (KG) as an alternative to cholesterol and the addition of a cationic (stearylamine) or anionic (dicethylphosphate) surfactant (qualitative factors); the percents of ethanol and the total volume of the hydration phase (quantitative factors) were the variables for the hydrophilic phase. The combined influence of these factors on the considered responses (encapsulation efficiency (EE%) and percent drug permeated at 180 min (P%)) was evaluated by means of a D-optimal design strategy. Graphic analysis of the effects indicated that maximization of the selected responses requested opposite levels of the considered factors: For example, KG and stearylamine were better for increasing EE%, and cholesterol and dicethylphosphate for increasing P%. In the second step, the Doehlert design, applied for the response-surface study of the quantitative factors, pointed out a negative interaction between percent ethanol and volume of the hydration phase and allowed prediction of the best formulation for maximizing drug permeation rate. Experimental P% data of the optimized formulation were inside the confidence interval (P < 0.05) calculated around the predicted value of the response. This proved the suitability of the proposed approach for optimizing the composition of liposomal formulations and predicting the effects of formulation variables on the considered experimental response. Moreover, the optimized formulation enabled a significant improvement (P < 0.05) of the drug anaesthetic effect with respect to the starting reference liposomal formulation, thus demonstrating its actually better therapeutic effectiveness. PMID:18569447

Mura, Paola; Capasso, Gaetano; Maestrelli, Francesca; Furlanetto, Sandra

2008-01-01

143

Design of vibration compensation interferometer for Experimental Advanced Superconducting Tokamak.  

PubMed

A vibration compensation interferometer (wavelength at 0.532 ?m) has been designed and tested for Experimental Advanced Superconducting Tokamak (EAST). It is designed as a sub-system for EAST far-infrared (wavelength at 432.5 ?m) poloarimeter/interferometer system. Two Acoustic Optical Modulators have been applied to produce the 1 MHz intermediate frequency. The path length drift of the system is lower than 2 wavelengths within 10 min test, showing the system stability. The system sensitivity has been tested by applying a periodic vibration source on one mirror in the system. The vibration is measured and the result matches the source period. The system is expected to be installed on EAST by the end of 2014. PMID:25430167

Yang, Y; Li, G S; Liu, H Q; Jie, Y X; Ding, W X; Brower, D L; Zhu, X; Wang, Z X; Zeng, L; Zou, Z Y; Wei, X C; Lan, T

2014-11-01

144

Design preferences and cognitive styles: experimentation by automated website synthesis  

PubMed Central

Background This article aims to demonstrate computational synthesis of Web-based experiments in undertaking experimentation on relationships among the participants' design preference, rationale, and cognitive test performance. The exemplified experiments were computationally synthesised, including the websites as materials, experiment protocols as methods, and cognitive tests as protocol modules. This work also exemplifies the use of a website synthesiser as an essential instrument enabling the participants to explore different possible designs, which were generated on the fly, before selection of preferred designs. Methods The participants were given interactive tree and table generators so that they could explore some different ways of presenting causality information in tables and trees as the visualisation formats. The participants gave their preference ratings for the available designs, as well as their rationale (criteria) for their design decisions. The participants were also asked to take four cognitive tests, which focus on the aspects of visualisation and analogy-making. The relationships among preference ratings, rationale, and the results of cognitive tests were analysed by conservative non-parametric statistics including Wilcoxon test, Krustal-Wallis test, and Kendall correlation. Results In the test, 41 of the total 64 participants preferred graphical (tree-form) to tabular presentation. Despite the popular preference for graphical presentation, the given tabular presentation was generally rated to be easier than graphical presentation to interpret, especially by those who were scored lower in the visualization and analogy-making tests. Conclusions This piece of evidence helps generate a hypothesis that design preferences are related to specific cognitive abilities. Without the use of computational synthesis, the experiment setup and scientific results would be impractical to obtain. PMID:22748000

2012-01-01

145

(The workshop on experimental design and quality improvement)  

SciTech Connect

This report, dated June 21, 1990, covers the trip to Taiwan of Dr. Toby J. Mitchell, Statistician in the Mathematical Sciences Section, Engineering Physics and Mathematics Division, Oak Ridge National Laboratory. The trip was supported by the Institute of Statistics of the Academia Sinica of the Republic of China (hereafter called the Institute''). The purpose of the trip was to attend and present an invited paper at the Workshop on Experimental Design and Quality Improvement held at the Institute in Taipei, Taiwan, June 11--13. The presented paper described two applications of recent work at ORNL in the design and analysis of computer experiments. The Institute was the only site visited. Principal contacts were with Dr. Min-Te Chao, the Director of the Institute, and with the other five speakers: Dr. V. N. Nair (AT T bell Laboratories), Professor R. A. Bailey (Rothamsted Experimental Station, UK), Professor S. Hedayat (University of Illinois, Chicago), Professor C. F. J. Wu (University of Waterloo, Canada), and Professor C. S. Cheng (University of California, Berkeley). The main activities consisted of attending the Workshop, contributing to the discussions, and presenting one of the talks. Informal technical discussions were somewhat limited, and mostly involved the other speakers. The main benefits to our research, which is funded by DOE's Applied Mathematical Sciences Program, was to gain greater international exposure for our work, and to discover new applications for it.

Mitchell, T.J.

1990-06-21

146

New charging strategy for lithium-ion batteries based on the integration of Taguchi method and state of charge estimation  

NASA Astrophysics Data System (ADS)

In this paper, a new charging strategy of lithium-polymer batteries (LiPBs) has been proposed based on the integration of Taguchi method (TM) and state of charge estimation. The TM is applied to search an optimal charging current pattern. An adaptive switching gain sliding mode observer (ASGSMO) is adopted to estimate the SOC which controls and terminates the charging process. The experimental results demonstrate that the proposed charging strategy can successfully charge the same types of LiPBs with different capacities and cycle life. The proposed charging strategy also provides much shorter charging time, narrower temperature variation and slightly higher energy efficiency than the equivalent constant current constant voltage charging method.

Vo, Thanh Tu; Chen, Xiaopeng; Shen, Weixiang; Kapoor, Ajay

2015-01-01

147

Quiet Clean Short-Haul Experimental Engine (QSCEE). Preliminary analyses and design report, volume 1  

NASA Technical Reports Server (NTRS)

The experimental propulsion systems to be built and tested in the 'quiet, clean, short-haul experimental engine' program are presented. The flight propulsion systems are also presented. The following areas are discussed: acoustic design; emissions control; engine cycle and performance; fan aerodynamic design; variable-pitch actuation systems; fan rotor mechanical design; fan frame mechanical design; and reduction gear design.

1974-01-01

148

An experimental design approach to retrospective exposure assessment.  

PubMed

There are several methods currently in use for retrospective estimation of quantitative exposure levels in occupational and environmental epidemiologic studies. The most popular is a job-exposure matrix approach using a combination of existing data and professional judgment. Another method is the use of statistical models based on available exposure data. The authors present an alternative approach using an experimental design in which several factors thought to affect exposure levels are identified and set at specific levels in a cross-classified design. This approach was used to estimate historical exposures to formaldehyde in a mortality study of embalmers. Exposures were estimated as a function of solution concentration, air exchange rate, and autopsied versus intact body. There were 12 combinations involving these 3 factors and a total of 25 embalming procedures (approximately 2 replicates of each combination) performed at a college of mortuary science. In addition to these design factors several covariates such as temperature, humidity, and the occurrence of spills were considered in an analysis of covariance statistical model. The results of the model prediction were validated against published measurements, and field samples were taken in several funeral homes. The overall accuracy of the model predictions was comparable to the variation found in replicate measurements of identical embalming procedures. PMID:8776195

Hornung, R W; Herrick, R F; Stewart, P A; Utterback, D F; Feigley, C E; Wall, D K; Douthit, D E; Hayes, R B

1996-03-01

149

Protein design algorithms predict viable resistance to an experimental antifolate.  

PubMed

Methods to accurately predict potential drug target mutations in response to early-stage leads could drive the design of more resilient first generation drug candidates. In this study, a structure-based protein design algorithm (K* in the OSPREY suite) was used to prospectively identify single-nucleotide polymorphisms that confer resistance to an experimental inhibitor effective against dihydrofolate reductase (DHFR) from Staphylococcus aureus. Four of the top-ranked mutations in DHFR were found to be catalytically competent and resistant to the inhibitor. Selection of resistant bacteria in vitro reveals that two of the predicted mutations arise in the background of a compensatory mutation. Using enzyme kinetics, microbiology, and crystal structures of the complexes, we determined the fitness of the mutant enzymes and strains, the structural basis of resistance, and the compensatory relationship of the mutations. To our knowledge, this work illustrates the first application of protein design algorithms to prospectively predict viable resistance mutations that arise in bacteria under antibiotic pressure. PMID:25552560

Reeve, Stephanie M; Gainza, Pablo; Frey, Kathleen M; Georgiev, Ivelin; Donald, Bruce R; Anderson, Amy C

2015-01-20

150

Formation of ultrafine deferasirox particles via rapid expansion of supercritical solution (RESS process) using Taguchi approach.  

PubMed

The poor water solubility of many drugs is a challenge in pharmaceutical research. Recently, there have been great interests in finding environmentally friendly methods producing fine particles of pharmaceutical products for applications in pharmaceutical engineering. A promising method to improve the bioavailability of pharmaceutical agents is the rapid expansion of supercritical solutions. Deferasirox (DFS), a tridentate chelator, requires two molecules for iron (III) coordination. The bioavailability (the percentage of the drug absorbed compared to its initial dosage) is limited by this insolubility. The effect of four different RESS parameters including, extraction temperature (308-318K), extraction pressure (140-200 bar), effective nozzle diameter (500-1200 ?m), with and without cosolvents were investigated on the size and morphology of the precipitated particles of deferasirox based on Taguchi design. The results show great reduction in the size of the precipitated particles of deferasirox (50 nm-5 ?m) via RESS process compared with the original particles of deferasirox (5-500 ?m). PMID:22583849

Asghari, Iman; Esmaeilzadeh, Feridun

2012-08-20

151

Simulation-based optimal Bayesian experimental design for nonlinear systems  

NASA Astrophysics Data System (ADS)

The optimal selection of experimental conditions is essential to maximizing the value of data for inference and prediction, particularly in situations where experiments are time-consuming and expensive to conduct. We propose a general mathematical framework and an algorithmic approach for optimal experimental design with nonlinear simulation-based models; in particular, we focus on finding sets of experiments that provide the most information about targeted sets of parameters. Our framework employs a Bayesian statistical setting, which provides a foundation for inference from noisy, indirect, and incomplete data, and a natural mechanism for incorporating heterogeneous sources of information. An objective function is constructed from information theoretic measures, reflecting expected information gain from proposed combinations of experiments. Polynomial chaos approximations and a two-stage Monte Carlo sampling method are used to evaluate the expected information gain. Stochastic approximation algorithms are then used to make optimization feasible in computationally intensive and high-dimensional settings. These algorithms are demonstrated on model problems and on nonlinear parameter inference problems arising in detailed combustion kinetics.

Huan, Xun; Marzouk, Youssef M.

2013-01-01

152

Computational Design and Experimental Validation of New Thermal Barrier Systems  

SciTech Connect

This project (10/01/2010-9/30/2013), “Computational Design and Experimental Validation of New Thermal Barrier Systems”, originates from Louisiana State University (LSU) Mechanical Engineering Department and Southern University (SU) Department of Computer Science. This proposal will directly support the technical goals specified in DE-FOA-0000248, Topic Area 3: Turbine Materials, by addressing key technologies needed to enable the development of advanced turbines and turbine-based systems that will operate safely and efficiently using coal-derived synthesis gases. We will develop novel molecular dynamics method to improve the efficiency of simulation on novel TBC materials; we will perform high performance computing (HPC) on complex TBC structures to screen the most promising TBC compositions; we will perform material characterizations and oxidation/corrosion tests; and we will demonstrate our new Thermal barrier coating (TBC) systems experimentally under Integrated gasification combined cycle (IGCC) environments. The durability of the coating will be examined using the proposed High Temperature/High Pressure Durability Test Rig under real syngas product compositions.

Guo, Shengmin; Yang, Shizhong; Khosravi, Ebrahim

2011-12-31

153

Experimental Reality: Principles for the Design of Augmented Environments  

NASA Astrophysics Data System (ADS)

The Laboratory of Design for Cognition at EDF R&D (LDC) is a living laboratory, which we created to develop Augmented Environment (AE) for collaborative work, more specifically “cognitive work” (white collars, engineers, office workers). It is a corporate laboratory in a large industry, where natural activity of real users is observed in a continuous manner in various spaces (project space, meeting room, lounge, etc.) The RAO room, an augmented meeting room, is used daily for “normal” meetings; it is also the “mother room” of all augmented meeting rooms in the company, where new systems, services, and devices are tested. The LDC has gathered a unique set of data on the use of AE, and developed various observation and design techniques, described in this chapter. LDC uses novel techniques of digital ethnography, some of which were invented there (SubCam, offsat) and some of which were developed elsewhere and adapted (360° video, WebDiver, etc.). At LDC, some new theories have also been developed to explain behavior and guide innovation: cognitive attractors, experimental reality, and the triple-determination framework.

Lahlou, Saadi

154

Experimental Charging Behavior of Orion UltraFlex Array Designs  

NASA Technical Reports Server (NTRS)

The present ground based investigations give the first definitive look describing the charging behavior of Orion UltraFlex arrays in both the Low Earth Orbital (LEO) and geosynchronous (GEO) environments. Note the LEO charging environment also applies to the International Space Station (ISS). The GEO charging environment includes the bounding case for all lunar mission environments. The UltraFlex photovoltaic array technology is targeted to become the sole power system for life support and on-orbit power for the manned Orion Crew Exploration Vehicle (CEV). The purpose of the experimental tests is to gain an understanding of the complex charging behavior to answer some of the basic performance and survivability issues to ascertain if a single UltraFlex array design will be able to cope with the projected worst case LEO and GEO charging environments. Stage 1 LEO plasma testing revealed that all four arrays successfully passed arc threshold bias tests down to -240 V. Stage 2 GEO electron gun charging tests revealed that only the front side area of indium tin oxide coated array designs successfully passed the arc frequency tests

Golofaro, Joel T.; Vayner, Boris V.; Hillard, Grover B.

2010-01-01

155

Taguchi methods applied to oxygen-enriched diesel engine experiments  

SciTech Connect

This paper describes a test series conducted on a six-cylinder diesel engine to study the impacts of controlled factors (i.e., oxygen content of the combustion air, water content of the fuel, fuel rate, and fuel-injection timing) on engine emissions using Taguchi methods. Three levels of each factor were used in the tests. Only the main effects of the factors were examined; no attempt was made to analyze the interactions among the factors. It was found that, as in the case of the single-cylinder engine tests, oxygen in the combustion air was very effective in reducing particulate and smoke emissions. Increases in NO[sub x] due to the oxygen enrichment observed in the single-cylinder tests also occurred in the present six-cylinder tests. Water in the emulsified fuel was found to be much less effective in decreasing NO[sub x] emissions for the six-cylinder engine than it was for the single-cylinder engine.

Marr, W.W.; Sekar, R.R.; Cole, R.L.; Marciniak, T.J. (Argonne National Lab., IL (United States)); Longman, D.E. (Autoresearch Labs., Inc., Chicago, IL (United States))

1992-01-01

156

Taguchi methods applied to oxygen-enriched diesel engine experiments  

SciTech Connect

This paper describes a test series conducted on a six-cylinder diesel engine to study the impacts of controlled factors (i.e., oxygen content of the combustion air, water content of the fuel, fuel rate, and fuel-injection timing) on engine emissions using Taguchi methods. Three levels of each factor were used in the tests. Only the main effects of the factors were examined; no attempt was made to analyze the interactions among the factors. It was found that, as in the case of the single-cylinder engine tests, oxygen in the combustion air was very effective in reducing particulate and smoke emissions. Increases in NO{sub x} due to the oxygen enrichment observed in the single-cylinder tests also occurred in the present six-cylinder tests. Water in the emulsified fuel was found to be much less effective in decreasing NO{sub x} emissions for the six-cylinder engine than it was for the single-cylinder engine.

Marr, W.W.; Sekar, R.R.; Cole, R.L.; Marciniak, T.J. [Argonne National Lab., IL (United States); Longman, D.E. [Autoresearch Labs., Inc., Chicago, IL (United States)

1992-12-01

157

Design and Experimental Validation of a Ducted Counter-rotating Axial-flow Fans System  

E-print Network

Design and Experimental Validation of a Ducted Counter-rotating Axial-flow Fans System H. Nouri,1 F'H^opital, 75013 Paris, France. An experimental study on the design of counter-rotating axial-flow fans was carried out. The fans were designed using an inverse method. In particular, the system is designed to have

Boyer, Edmond

158

Optimization of alkaline protease production by Bacillus sp. using Taguchi methodology.  

PubMed

Optimization of alkaline protease production parameters by Bacillus sp. was investigated using Taguchi methodology. The pH of the medium was observed to be the most significant factor among all selected optimization parameters at an individual level. The combinatorial influence of least significant factors, inoculum level and salt solution concentration (at the individual level), resulted in an interacting severity index of 76%, suggesting their interactive role in the regulation of protease production in this microbial species. Protease production could be improved more than 100% with Taguchi's optimized conditions of the medium composition by this microorganism. PMID:15695842

Prakasham, R S; Rao, Ch Subba; Rao, R Sreenivas; Rajesham, S; Sarma, P N

2005-02-01

159

Dynamic pathway modeling: feasibility analysis and optimal experimental design.  

PubMed

A major challenge in systems biology is to evaluate the feasibility of a biological research project prior to its realization. Since experiments are animals-, cost- and time-consuming, approaches allowing researchers to discriminate alternative hypotheses with a minimal set of experiments are highly desirable. Given a null hypothesis and alternative model, as well as laboratory constraints like observable players, sample size, noise level, and stimulation options, we suggest a method to obtain a list of required experiments in order to significantly reject the null hypothesis model M0 if a specified alternative model MA is realized. For this purpose, we estimate the power to detect a violation of M0 by means of Monte Carlo simulations. Iteratively, the power is maximized over all feasible stimulations of the system using multi-experiment fitting, leading to an optimal combination of experimental settings to discriminate the null hypothesis and alternative model. We prove the importance of simultaneous modeling of combined experiments with quantitative, highly sampled in vivo measurements from the Jak/STAT5 signaling pathway in fibroblasts, stimulated with erythropoietin (Epo). Afterwards we apply the presented iterative experimental design approach to the Jak/STAT3 pathway of primary hepatocytes stimulated with IL-6. Our approach offers the possibility of deciding which scientific questions can be answered based on existing laboratory constraints. To be able to concentrate on feasible questions on account of inexpensive computational simulations yields not only enormous cost and time saving, but also helps to specify realizable, systematic research projects in advance. PMID:18033750

Maiwald, Thomas; Kreutz, Clemens; Pfeifer, Andrea C; Bohl, Sebastian; Klingmüller, Ursula; Timmer, Jens

2007-12-01

160

Two point microstructure sensitive design and experimental verification  

NASA Astrophysics Data System (ADS)

Rectangular models of material microstructure are described by their 1- and 2-point (spatial) correlation statistics of placement of local state. It is illustrated that generalized 2-point Hashin-Shtrikman bounds for elastic stiffness can be obtained that are linear in components of the correlation statistics. The concept of an eigen-microstructure within the microstructure hull is introduced. A method is developed for generating a sequence of archetypes of eigen-microstructure, from the 2-point correlation statistics of local state, assuming that the 1-point statistics are stationary. The method is illustrated by a case study. Extension of the first-order theory of microstructure design to considerations of morphological texture is addressed. It is shown that the correlation functions can be expressed in terms of an intermediate construct, called the texture function; the correlation functions have quadratic dependence in the texture functions. A complete (finite) texture hull is readily constructed for the texture functions in Fourier space, and is found to be a convex polytope. Eigen-texture functions occupy its corner (extreme) points. This gives rise to (combined) properties closures, from which second-order microstructure design can proceed. This is demonstrated in a brief case study. Experimental methods are introduced for obtaining two-point microstructure pair correlation functions in polycrystalline material. A particular tessellation of the fundamental zone of Euler angle space is described; individual orientations of the data set are binned into discrete tesserae. Elementary relationships between the two-point pair correlation functions and the grain size distribution and coherence length are explored. The one- and two-point distributions of orientation were recovered for three textures (as-received stainless steel, as-received copper and copper with cube texture). Elastic bounds for these textures are calculated including one-point bounds and generalized Hashin-Shtrikman bounds. Finite Element Analysis (FEA), incorporating the estimated elastic properties, is used to predict the strain field around a hole in the plate subjected to uniaxial loading. High Sensitivity Moire Interferometry (HSMI) is used to measure the strain experimentally. The results show that the two-point bounds on effective properties lead to predictions in better agreement with the HSMI results as compared to the one-point bounds.

Gao, Xiang

161

Sparsely sampling the sky: a Bayesian experimental design approach  

NASA Astrophysics Data System (ADS)

The next generation of galaxy surveys will observe millions of galaxies over large volumes of the Universe. These surveys are expensive both in time and cost, raising questions regarding the optimal investment of this time and money. In this work, we investigate criteria for selecting amongst observing strategies for constraining the galaxy power spectrum and a set of cosmological parameters. Depending on the parameters of interest, it may be more efficient to observe a larger, but sparsely sampled, area of sky instead of a smaller contiguous area. In this work, by making use of the principles of Bayesian experimental design, we will investigate the advantages and disadvantages of the sparse sampling of the sky and discuss the circumstances in which a sparse survey is indeed the most efficient strategy. For the Dark Energy Survey (DES), we find that by sparsely observing the same area in a smaller amount of time, we only increase the errors on the parameters by a maximum of 0.45 per cent. Conversely, investing the same amount of time as the original DES to observe a sparser but larger area of sky, we can in fact constrain the parameters with errors reduced by 28 per cent.

Paykari, P.; Jaffe, A. H.

2013-08-01

162

Mental synthesis and creativity in design: an experimental examination  

Microsoft Academic Search

This research examined design issues of creativity, mental synthesis, and drawing by conducting two experiments. These experiments compared and contrasted 3D designers, 2D designers, and Non-designers. The first experiment investigated if designers were more creative than non-designers when given creative mental synthesis tasks. We found they were. The second experiment investigated the relationship between drawing and creative mental synthesis. We

Vasilije Kokotovich; Terry Purcell

2000-01-01

163

Bearing diagnosis based on Mahalanobis-Taguchi-Gram-Schmidt method  

NASA Astrophysics Data System (ADS)

A methodology is developed for defect type identification in rolling element bearings using the integrated Mahalanobis-Taguchi-Gram-Schmidt (MTGS) method. Vibration data recorded from bearings with seeded defects on outer race, inner race and balls are processed in time, frequency, and time-frequency domains. Eleven damage identification parameters (RMS, Peak, Crest Factor, and Kurtosis in time domain, amplitude of outer race, inner race, and ball defect frequencies in FFT spectrum and HFRT spectrum in frequency domain and peak of HHT spectrum in time-frequency domain) are computed. Using MTGS, these damage identification parameters (DIPs) are fused into a single DIP, Mahalanobis distance (MD), and gain values for the presence of all DIPs are calculated. The gain value is used to identify the usefulness of DIP and the DIPs with positive gain are again fused into MD by using Gram-Schmidt Orthogonalization process (GSP) in order to calculate Gram-Schmidt Vectors (GSVs). Among the remaining DIPs, sign of GSVs of frequency domain DIPs is checked to classify the probable defect. The approach uses MTGS method for combining the damage parameters and in conjunction with the GSV classifies the defect. A Defect Occurrence Index (DOI) is proposed to rank the probability of existence of a type of bearing damage (ball defect/inner race defect/outer race defect/other anomalies). The methodology is successfully validated on vibration data from a different machine, bearing type and shape/configuration of the defect. The proposed methodology is also applied on the vibration data acquired from the accelerated life test on the bearings, which established the applicability of the method on naturally induced and naturally progressed defect. It is observed that the methodology successfully identifies the correct type of bearing defect. The proposed methodology is also useful in identifying the time of initiation of a defect and has potential for implementation in a real time environment.

Shakya, Piyush; Kulkarni, Makarand S.; Darpe, Ashish K.

2015-02-01

164

Optimization of experimental design in fMRI: a general framework using a genetic algorithm  

E-print Network

Optimization of experimental design in fMRI: a general framework using a genetic algorithm Tor D uses a genetic algorithm (GA), a class of flexible search algorithms that optimize designs with respect genetic algorithms may be applied to experimental design for fMRI, and we use the framework to explore

165

Combining adaptive and designed statistical experimentation : process improvement, data classification, experimental optimization and model building  

E-print Network

Research interest in the use of adaptive experimentation has returned recently. This historic technique adapts and learns from each experimental run but requires quick runs and large effects. The basis of this renewed ...

Foster, Chad Ryan

2009-01-01

166

PD output feedback control design for robot manipulators: Experimental results  

Microsoft Academic Search

In this paper, we design and implement model independent observer-controller based output feedback method for robot manipulators. The control design uses only proportional and derivative (PD) error terms for trajectory tracking of nonlinear robot manipulators. The unknown velocity signals is generated by the output of the linear observer. The design is very simple in the sense that it does not

Shafiqui Islam; P. X. Liu; A. El Saddick

2011-01-01

167

A Note on Small Composite Designs for Sequential Experimentation  

Microsoft Academic Search

The recommended approach to experiments using the response surface methodology is sequential, i.e., experiments should be conducted iteratively. Al the first stage, a first-order design, usually an orthogonal two-level design (with a few center points) is used to find out whether the current region is appropriate and to allow the estimation of main effects (and possibly some interactions). The design

Nam-Ky Nguyen; Dennis K. J. Lin

2011-01-01

168

Design support systems for process engineering—II. KBDS: An experimental prototype  

Microsoft Academic Search

KBDS is a prototype design support system for process engineering. It was created as an experimental vehicle to test and develop ideas about the representation of the design process, and to demonstrate how such a representation can be used to support the design activity. Our starting point is a representation of the design process consisting of three spaces: One for

R. Bañares-Alcántara; H. M. S. Lababidi

1995-01-01

169

Teaching Simple Experimental Design to Undergraduates: Do Your Students Understand the Basics?  

ERIC Educational Resources Information Center

This article provides instructors with guidelines for teaching simple experimental design for the comparison of two treatment groups. Two designs with specific examples are discussed along with common misconceptions that undergraduate students typically bring to the experiment design process. Features of experiment design that maximize power and…

Hiebert, Sara M.

2007-01-01

170

Optimisation of machining parameters of glass-fibre-reinforced plastic (GFRP) pipes by desirability function analysis using Taguchi technique  

Microsoft Academic Search

This paper presents a new approach for optimizing the machining parameters on turning glass-fibre-reinforced plastic (GFRP)\\u000a pipes. Optimisation of machining parameters was done by an analysis called desirability function analysis, which is a useful\\u000a tool for optimizing multi-response problems. In this work, based on Taguchi’s L18 orthogonal array, turning experiments were conducted for filament wound and hand layup GFRP pipes

A. Naveen Sait; S. Aravindan; A. Noorul Haq

2009-01-01

171

Return to Our Roots: Raising Radishes To Teach Experimental Design.  

ERIC Educational Resources Information Center

To provide practice in making design decisions, collecting and analyzing data, and writing and documenting results, a professor of statistics has his graduate students in statistics and research methodology classes design and perform an experiment on the effects of fertilizers on the growth of radishes. This project has been required of students…

Stallings, William M.

172

Software Design Issues for Experimentation in Ubiquitous Computing  

Microsoft Academic Search

Designing smart user interfaces is a key challenge in making a new appliance useful. This is espe- cially difficult to achieve when input devices such as keyboard and mouse which allow a very flexible way of interaction with the system in a static en- vironment are not handy in a mobile environment. Good user interface design is not the application

Thomas Reicher; Timo Kosch; BMW AG

2001-01-01

173

Critical Zone Experimental Design to Assess Soil Processes and Function  

NASA Astrophysics Data System (ADS)

Through unsustainable land use practices, mining, deforestation, urbanisation and degradation by industrial pollution, soil losses are now hypothesized to be much faster (100 times or more) than soil formation - with the consequence that soil has become a finite resource. The crucial challenge for the international research community is to understand the rates of processes that dictate soil mass stocks and their function within Earth's Critical Zone (CZ). The CZ is the environment where soils are formed, degrade and provide their essential ecosystem services. Key among these ecosystem services are food and fibre production, filtering, buffering and transformation of water, nutrients and contaminants, storage of carbon and maintaining biological habitat and genetic diversity. We have initiated a new research project to address the priority research areas identified in the European Union Soil Thematic Strategy and to contribute to the development of a global network of Critical Zone Observatories (CZO) committed to soil research. Our hypothesis is that the combined physical-chemical-biological structure of soil can be assessed from first-principles and the resulting soil functions can be quantified in process models that couple the formation and loss of soil stocks with descriptions of biodiversity and nutrient dynamics. The objectives of this research are to 1. Describe from 1st principles how soil structure influences processes and functions of soils, 2. Establish 4 European Critical Zone Observatories to link with established CZOs, 3. Develop a CZ Integrated Model of soil processes and function, 4. Create a GIS-based modelling framework to assess soil threats and mitigation at EU scale, 5. Quantify impacts of changing land use, climate and biodiversity on soil function and its value and 6. Form with international partners a global network of CZOs for soil research and deliver a programme of public outreach and research transfer on soil sustainability. The experimental design studies soil processes across the temporal evolution of the soil profile, from its formation on bare bedrock, through managed use as productive land to its degradation under longstanding pressures from intensive land use. To understand this conceptual life cycle of soil, we have selected 4 European field sites as Critical Zone Observatories. These are to provide data sets of soil parameters, processes and functions which will be incorporated into the mathematical models. The field sites are 1) the BigLink field station which is located in the chronosequence of the Damma Glacier forefield in alpine Switzerland and is established to study the initial stages of soil development on bedrock; 2) the Lysina Catchment in the Czech Republic which is representative of productive soils managed for intensive forestry, 3) the Fuchsenbigl Field Station in Austria which is an agricultural research site that is representative of productive soils managed as arable land and 4) the Koiliaris Catchment in Crete, Greece which represents degraded Mediterranean region soils, heavily impacted by centuries of intensive grazing and farming, under severe risk of desertification.

Banwart, Steve

2010-05-01

174

Design, experimentation, and modeling of a novel continuous biodrying process  

NASA Astrophysics Data System (ADS)

Massive production of sludge in the pulp and paper industry has made the effective sludge management increasingly a critical issue for the industry due to high landfill and transportation costs, and complex regulatory frameworks for options such as sludge landspreading and composting. Sludge dewatering challenges are exacerbated at many mills due to improved in-plant fiber recovery coupled with increased production of secondary sludge, leading to a mixed sludge with a high proportion of biological matter which is difficult to dewater. In this thesis, a novel continuous biodrying reactor was designed and developed for drying pulp and paper mixed sludge to economic dry solids level so that the dried sludge can be economically and safely combusted in a biomass boiler for energy recovery. In all experimental runs the economic dry solids level was achieved, proving the process successful. In the biodrying process, in addition to the forced aeration, the drying rates are enhanced by biological heat generated through the microbial activity of mesophilic and thermophilic microorganisms naturally present in the porous matrix of mixed sludge. This makes the biodrying process more attractive compared to the conventional drying techniques because the reactor is a self-heating process. The reactor is divided into four nominal compartments and the mixed sludge dries as it moves downward in the reactor. The residence times were 4-8 days, which are 2-3 times shorter than the residence times achieved in a batch biodrying reactor previously studied by our research group for mixed sludge drying. A process variable analysis was performed to determine the key variable(s) in the continuous biodrying reactor. Several variables were investigated, namely: type of biomass feed, pH of biomass, nutrition level (C/N ratio), residence times, recycle ratio of biodried sludge, and outlet relative humidity profile along the reactor height. The key variables that were identified in the continuous biodrying reactor were the type of biomass feed and the outlet relative humidity profiles. The biomass feed is mill specific and since one mill was studied for this study, the nutrition level of the biomass feed was found adequate for the microbial activity, and hence the type of biomass is a fixed parameter. The influence of outlet relative humidity profile was investigated on the overall performance and the complexity index of the continuous biodrying reactor. The best biodrying efficiency was achieved at an outlet relative humidity profile which controls the removal of unbound water at the wet-bulb temperature in the 1st and 2nd compartments of the reactor, and the removal of bound water at the dry-bulb temperature in the 3rd and 4th compartments. Through a systematic modeling approach, a 2-D model was developed to describe the transport phenomena in the continuous biodrying reactor. The results of the 2-D model were in satisfactory agreement with the experimental data. It was found that about 30% w/w of the total water removal (drying rate) takes place in the 1st and 2nd compartments mainly under a convection dominated mechanism, whereas about 70% w/w of the total water removal takes place in the 3rd and 4th compartments where a bioheat-diffusion dominated mechanism controls the transport phenomena. The 2-D model was found to be an appropriate tool for the estimation of the total water removal rate (drying rate) in the continuous biodrying reactor when compared to the 1-D model. A dimensionless analysis was performed on the 2-D model and established the preliminary criteria for the scale-up of the continuous biodrying process. Finally, a techno-economic assessment of the continuous biodrying process revealed that there is great potential for the implementation of the biodrying process in Canadian pulp and paper mills. The techno-economic results were compared to the other competitive existing drying technologies. It was proven that the continuous biodrying process results in significant economic benefits and has great potential to address the current industr

Navaee-Ardeh, Shahram

175

AERODYNAMIC DESIGN OF UNMANNED AND SCALED SUPERSONIC EXPERIMENTAL AIRPLANE IN JAPAN  

Microsoft Academic Search

This paper describes the aerodynamic design of the unmanned and scaled supersonic experimental airplanes promoted by Japan Aerospace Exploration Agency (JAXA). The main goal of the experimental airplane program is to develop an advanced aerodynamic design technology for the next generation SST. In the program conventional and innovative drag reduction technologies were mainly considered. The first airplane had no propulsion

Kenji Yoshida; Yoshikazu Makino

176

Web-Based Learning Support for Experimental Design in Molecular Biology: A Top-Down Approach  

ERIC Educational Resources Information Center

An important learning goal of a molecular biology curriculum is the attainment of a certain competence level in experimental design. Currently, undergraduate students are confronted with experimental approaches in textbooks, lectures and laboratory courses. However, most students do not reach a satisfactory level of competence in the designing of…

Aegerter-Wilmsen, Tinri; Hartog, Rob; Bisseling, Ton

2003-01-01

177

Design and Experimental Validation of a Ducted Counter-rotating Axial-flow Fans System  

E-print Network

Design and Experimental Validation of a Ducted Counter-rotating Axial-flow Fans System H. Nouri, F of the present study on ducted counter-rotating axial-flow fans in subsonic regime is to find out a design method Paris, France. An experimental study on counter-rotating axial-flow fans was carried out. The fans

178

Central Composite experimental design applied to removal of lead and nickel from sand  

Microsoft Academic Search

The aim of this study was to apply Central Composite experimental design in the removal of lead and nickel ions from sand by electrokinetic remediation. Sand was used for an initial study since it is inert, thus making it possible to analyze the parameters influencing the process. Central Composite Design was used to create an experimental program to provide data

V. V. Guaracho; N. M. S. Kaminari; M. J. J. S. Ponte; H. A. Ponte

2009-01-01

179

Measurement of uranium enrichment by gamma spectroscopy: result of an experimental design  

E-print Network

PAPER Measurement of uranium enrichment by gamma spectroscopy: result of an experimental design Gamma spectroscopy is commonly used in nuclear safeguards to measure uranium enrichment. An experimental design has been carried out for the measurement of uranium enrichment using this technique with different

180

Using Propensity Scores in Quasi-Experimental Designs to Equate Groups  

ERIC Educational Resources Information Center

Education research rarely lends itself to large scale experimental research and true randomization, leaving the researcher to quasi-experimental designs. The problem with quasi-experimental research is that underlying factors may impact group selection and lead to potentially biased results. One way to minimize the impact of non-randomization is…

Lane, Forrest C.; Henson, Robin K.

2010-01-01

181

Using introductory labs to engage students in experimental design  

NSDL National Science Digital Library

The Investigative Science Learning Environment (ISLE) engages students in processes mirroring the practice of science. Laboratories play a central role in this learning environment. Students in ISLE laboratories design their own experiments to investigate new phenomena, test hypotheses, and solve realistic problems. We discuss various issues associated with implementing these labs in large enrollment introductory physics courses. We present examples of experiments that students design, include a sample of student work, and discuss issues related to the choice of experiments for design and practical implementation. We also review assessment techniques and show results of students' acquisition and transfer of some laboratory-related abilities.

Etkina, Eugenia; Murthy, Sahana; Zou, Xueli

2009-04-13

182

Numerical and Experimental Analysis of Multi-Stage Axial Turbine Performance at Design and Off-Design Conditions  

E-print Network

D cylindrical blades to 3D bowed blade designs in abating the secondary flow effects which are dominant loss generators.However, comparing experimentally measured performance results to numerically predicted shows a clear deficiency, where the CFD...

Abdelfattah, Sherif Alykadry

2013-08-07

183

WEXTOR: A Web-based tool for generating and visualizing experimental designs and procedures  

Microsoft Academic Search

WEXTOR is a Javascript-based experiment generator and teaching tool on the World-Wide Web that can be used to design laboratory\\u000a and Web experiments in a guided step-by-step process. It dynamically creates the customized Web pages and Javascripts needed\\u000a for the experimental procedure and provides experimenters with a print-ready visual display of their experimental design.\\u000a WEXTOR flexibly supportscomplete and incomplete factorial

Ulf-Dietrich Reips; Christoph Neuhaus

2002-01-01

184

Design and experimental analysis of legged locomotive robots  

E-print Network

In this thesis, I present the design and motion-capture analysis of two previously well-studied dynamic-walking machines, the rimless wheel and the compass gait robot. These robots were the basis for my undergraduate ...

Villabona, Timothy J

2009-01-01

185

Design and Experimental Study on Spinning Solid Rocket Motor  

Microsoft Academic Search

\\u000a The study on spinning solid rocket motor (SRM) which used as power plant of twice throwing structure of aerial submunition\\u000a was introduced. This kind of SRM which with the structure of tangential multi-nozzle consists of a combustion chamber, propellant\\u000a charge, 4 tangential nozzles, ignition device, etc. Grain design, structure design and prediction of interior ballistic performance\\u000a were described, and problem

Heng Xue; Chunlan Jiang; Zaicheng Wang

2009-01-01

186

Leveraging the Experimental Method to Inform Solar Cell Design  

ERIC Educational Resources Information Center

In this article, the underlying logic of experimentation is exemplified within the context of a photoelectrical experiment for students taking a high school engineering, technology, or chemistry class. Students assume the role of photochemists as they plan, fabricate, and experiment with a solar cell made of copper and an aqueous solution of…

Rose, Mary Annette; Ribblett, Jason W.; Hershberger, Heather Nicole

2010-01-01

187

Association mapping: critical considerations shift from genotyping to experimental design  

Technology Transfer Automated Retrieval System (TEKTRAN)

The goal of many plant scientists’ research is to explain natural phenotypic variation in terms of simple changes in DNA sequence. Traditionally, linkage mapping has been the most commonly employed method to reach this goal: experimental crosses are made to generate a family with known relatedness ...

188

ASSESSMENT OF DERMAL ETHANOL EMISSION SENSORS: EXPERIMENTAL DESIGN  

Microsoft Academic Search

This paper discusses methods that will be used to experimentally determine the limitations of transdermal ethanol alcohol sensors when used on human subjects. Transdermal ethanol sensors are used to measure the concentration of ethanol emitted by the surface of the skin. The maximum concentration of ethanol in the skin is proportional to the concentration of ethanol in the blood stream

Gregory Webster; Hampton C. Gabler

189

DESIGN OF THE SMALL-SCALE EXPERIMENTAL ADS: MYRRHA  

Microsoft Academic Search

Since 1998, SCKCEN, in partnership with IBA s.a. and many European research labora- tories, is desig ning a multipurpose Accelerator Driven System (ADS) - MYRRHA - and is conducting an associated R&D support programme. MYRRHA aims to serve as a basis for the European experimental ADS to provide protons and neutrons for various R&D applications . Besides an overall configuration

Dirk Maes

190

Development and Validation of a Rubric for Diagnosing Students’ Experimental Design Knowledge and Difficulties  

PubMed Central

It is essential to teach students about experimental design, as this facilitates their deeper understanding of how most biological knowledge was generated and gives them tools to perform their own investigations. Despite the importance of this area, surprisingly little is known about what students actually learn from designing biological experiments. In this paper, we describe a rubric for experimental design (RED) that can be used to measure knowledge of and diagnose difficulties with experimental design. The development and validation of the RED was informed by a literature review and empirical analysis of undergraduate biology students’ responses to three published assessments. Five areas of difficulty with experimental design were identified: the variable properties of an experimental subject; the manipulated variables; measurement of outcomes; accounting for variability; and the scope of inference appropriate for experimental findings. Our findings revealed that some difficulties, documented some 50 yr ago, still exist among our undergraduate students, while others remain poorly investigated. The RED shows great promise for diagnosing students’ experimental design knowledge in lecture settings, laboratory courses, research internships, and course-based undergraduate research experiences. It also shows potential for guiding the development and selection of assessment and instructional activities that foster experimental design.

Dasgupta, Annwesa P.; Anderson, Trevor R.

2014-01-01

191

Central composite experimental design applied to the catalytic aromatization of isophorone to 3,5-xylenol  

Microsoft Academic Search

The aim of this study was to apply experimental design in the optimization of catalytic aromatization of isophorone to 3,5-xylenol to improve 3,5-xylenol selectivity. The central composite design was used to design an experimental program to provide data to model the effects of various factors on 3,5-xylenol selectivity (Y). The variables chosen were Cr2O3 loading (X1), reaction temperature (X2) and

Xian Zhang; Rijie Wang; Xiaoxia Yang; Jingang Yu

2007-01-01

192

Design and evaluation of experimental ceramic automobile thermal reactors  

NASA Technical Reports Server (NTRS)

The results obtained in an exploratory evaluation of ceramics for automobile thermal reactors are summarized. Candidate ceramic materials were evaluated in several reactor designs by using both engine-dynamometer and vehicle road tests. Silicon carbide contained in a corrugated-metal support structure exhibited the best performance, lasting 1100 hr in engine-dynamometer tests and more than 38,600 km (24000 miles) in vehicle road tests. Although reactors containing glass-ceramic components did not perform as well as those containing silicon carbide, the glass-ceramics still offer good potential for reactor use with improved reactor designs.

Stone, P. L.; Blankenship, C. P.

1974-01-01

193

Design and evaluation of experimental ceramic automobile thermal reactors  

NASA Technical Reports Server (NTRS)

The paper summarizes the results obtained in an exploratory evaluation of ceramics for automobile thermal reactors. Candidate ceramic materials were evaluated in several reactor designs using both engine dynamometer and vehicle road tests. Silicon carbide contained in a corrugated metal support structure exhibited the best performance, lasting 1100 hours in engine dynamometer tests and for more than 38,600 kilimeters (24,000 miles) in vehicle road tests. Although reactors containing glass-ceramic components did not perform as well as silicon carbide, the glass-ceramics still offer good potential for reactor use with improved reactor designs.

Stone, P. L.; Blankenship, C. P.

1974-01-01

194

EXPERIMENTAL DESIGN AND INSTRUMENTATION FOR A FIELD EXPERIMENT  

EPA Science Inventory

This report concerns the design of a field experiment for a military setting in which the effects of carbon monoxide on neurobehavioral variables are to be studied. ield experiment is distinguished from a survey by the fact that independent variables are manipulated, just as in t...

195

Creativity in Advertising Design Education: An Experimental Study  

ERIC Educational Resources Information Center

Have you ever thought about why qualities whose definitions are elusive, such as those of a sunset or a half-opened rose, affect us so powerfully? According to de Saussure (Course in general linguistics, 1983), the making of meanings is closely related to the production and interpretation of signs. All types of design, including advertising…

Cheung, Ming

2011-01-01

196

Optimizing Experimental Designs Relative to Costs and Effect Sizes.  

ERIC Educational Resources Information Center

A general model is derived for the purpose of efficiently allocating integral numbers of units in multi-level designs given prespecified power levels. The derivation of the model is based on a constrained optimization problem that maximizes a general form of a ratio of expected mean squares subject to a budget constraint. This model provides more…

Headrick, Todd C.; Zumbo, Bruno D.

197

Recent developments in optimal experimental designs for functional magnetic resonance imaging  

PubMed Central

Functional magnetic resonance imaging (fMRI) is one of the leading brain mapping technologies for studying brain activity in response to mental stimuli. For neuroimaging studies utilizing this pioneering technology, there is a great demand of high-quality experimental designs that help to collect informative data to make precise and valid inference about brain functions. This paper provides a survey on recent developments in experimental designs for fMRI studies. We briefly introduce some analytical and computational tools for obtaining good designs based on a specified design selection criterion. Research results about some commonly considered designs such as blocked designs, and m-sequences are also discussed. Moreover, we present a recently proposed new type of fMRI designs that can be constructed using a certain type of Hadamard matrices. Under certain assumptions, these designs can be shown to be statistically optimal. Some future research directions in design of fMRI experiments are also discussed. PMID:25071884

Kao, Ming-Hung; Temkit, M'hamed; Wong, Weng Kee

2014-01-01

198

Design and Experimental Verification of Real-Time Mechanisms for Middleware for Networked Control  

E-print Network

Design and Experimental Verification of Real-Time Mechanisms for Middleware for Networked Control timeliness requirements. We describe the design of real-time enhancements to Etherware, a middleware at the right time. Typically, control engineers design a control system by implicitly assuming the timely

199

A rational design change methodology based on experimental and analytical modal analysis  

SciTech Connect

A design methodology that integrates analytical modeling and experimental characterization is presented. This methodology represents a powerful tool for making rational design decisions and changes. An example of its implementation in the design, analysis, and testing of a precisions machine tool support structure is given.

Weinacht, D.J.; Bennett, J.G.

1993-08-01

200

EXPERIMENTAL INVESTIGATIONS ON THE DESIGN OF A DUCTED COUNTER-ROTATING AXIAL FLOW FANS SYSTEM  

E-print Network

EXPERIMENTAL INVESTIGATIONS ON THE DESIGN OF A DUCTED COUNTER-ROTATING AXIAL FLOW FANS SYSTEM-rotating axial-flow fans in a ducted-flow configuration was carried out. The fans were designed using an inverse to design axial-flow fans with very low specific speed = Q (pt/)3/4 with the mean angular velocity, Q

Boyer, Edmond

201

Single-Case Experimental Designs: A Systematic Review of Published Research and Current Standards  

ERIC Educational Resources Information Center

This article systematically reviews the research design and methodological characteristics of single-case experimental design (SCED) research published in peer-reviewed journals between 2000 and 2010. SCEDs provide researchers with a flexible and viable alternative to group designs with large sample sizes. However, methodological challenges have…

Smith, Justin D.

2012-01-01

202

Treatment of vinasses by electrocoagulation–electroflotation using the Taguchi method  

Microsoft Academic Search

Taguchi method has been applied in the treatment of vinasse from distillery for assess the performance of the process of electrocoagulation–electroflotation in the removal of total solids, turbidity and total organic carbon (TOC). The variables of study were initial pH, current density, concentration of hydrogen peroxide and material of the electrodes.We obtained removals of 50%, 89% and 25% for total

Javier A. Davila; Fiderman Machuca; Nilson Marrianga

2011-01-01

203

High-power CMUTs: design and experimental verification.  

PubMed

Capacitive micromachined ultrasonic transducers (CMUTs) have great potential to compete with piezoelectric transducers in high-power applications. As the output pressures increase, nonlinearity of CMUT must be reconsidered and optimization is required to reduce harmonic distortions. In this paper, we describe a design approach in which uncollapsed CMUT array elements are sized so as to operate at the maximum radiation impedance and have gap heights such that the generated electrostatic force can sustain a plate displacement with full swing at the given drive amplitude. The proposed design enables high output pressures and low harmonic distortions at the output. An equivalent circuit model of the array is used that accurately simulates the uncollapsed mode of operation. The model facilities the design of CMUT parameters for high-pressure output, without the intensive need for computationally involved FEM tools. The optimized design requires a relatively thick plate compared with a conventional CMUT plate. Thus, we used a silicon wafer as the CMUT plate. The fabrication process involves an anodic bonding process for bonding the silicon plate with the glass substrate. To eliminate the bias voltage, which may cause charging problems, the CMUT array is driven with large continuous wave signals at half of the resonant frequency. The fabricated arrays are tested in an oil tank by applying a 125-V peak 5-cycle burst sinusoidal signal at 1.44 MHz. The applied voltage is increased until the plate is about to touch the bottom electrode to get the maximum peak displacement. The observed pressure is about 1.8 MPa with -28 dBc second harmonic at the surface of the array. PMID:22718878

Yamaner, F Yalçin; Olçum, Selim; O?uz, H Ka?an; Bozkurt, Ayhan; Köymen, Hayrettin; Atalar, Abdullah

2012-06-01

204

System Design and Experimental Development of the Kalina Cycle Technology  

E-print Network

work. The amount of energy \\~hich may be converted from any form into mechanical energy is referred to as exergy. The ratio of the system's mechanical work to the exergy of the heat source is referred to as exergeti calor thermodynamic efficiency... the power industry and techni of Amalia cal community. It is now time to build a prototype. PROTOTYPE PROJECT-CANOGA PARK CALIFORNIA Confirmation of the process design will be established through prototype testing at the Energy Technology Engineering...

Kalina, A. I.; Leibowitz, H. M.

205

Tocorime Apicu: design and validation of an experimental search engine  

NASA Astrophysics Data System (ADS)

In the development of an integrated, experimental search engine, Tocorime Apicu, the incorporation and emulation of the evolutionary aspects of the chosen biological model (honeybees) and the field of high-performance knowledge discovery in databases results in the coupling of diverse fields of research: evolutionary computations, biological modeling, machine learning, statistical methods, information retrieval systems, active networks, and data visualization. The use of computer systems provides inherent sources of self-similarity traffic that result from the interaction of file transmission, caching mechanisms, and user-related processes. These user-related processes are initiated by the user, application programs, or the operating system (OS) for the user's benefit. The effect of Web transmission patterns, coupled with these inherent sources of self-similarity associated with the above file system characteristics, provide an environment for studying network traffic. The goal of the study was client-based, but with no user interaction. New methodologies and approaches were needed as network packet traffic increased in the LAN, LAN+WAN, and WAN. Statistical tools and methods for analyzing datasets were used to organize data captured at the packet level for network traffic between individual source/destination pairs. Emulation of the evolutionary aspects of the biological model equips the experimental search engine with an adaptive system model which will eventually have the capability to evolve with an ever- changing World Wide Web environment. The results were generated using a LINUX OS.

Walker, Reginald L.

2001-07-01

206

Applying the Taguchi Method to River Water Pollution Remediation Strategy Optimization  

PubMed Central

Optimization methods usually obtain the travel direction of the solution by substituting the solutions into the objective function. However, if the solution space is too large, this search method may be time consuming. In order to address this problem, this study incorporated the Taguchi method into the solution space search process of the optimization method, and used the characteristics of the Taguchi method to sequence the effects of the variation of decision variables on the system. Based on the level of effect, this study determined the impact factor of decision variables and the optimal solution for the model. The integration of the Taguchi method and the solution optimization method successfully obtained the optimal solution of the optimization problem, while significantly reducing the solution computing time and enhancing the river water quality. The results suggested that the basin with the greatest water quality improvement effectiveness is the Dahan River. Under the optimal strategy of this study, the severe pollution length was reduced from 18 km to 5 km. PMID:24739765

Yang, Tsung-Ming; Hsu, Nien-Sheng; Chiu, Chih-Chiang; Wang, Hsin-Ju

2014-01-01

207

Applying the Taguchi method to river water pollution remediation strategy optimization.  

PubMed

Optimization methods usually obtain the travel direction of the solution by substituting the solutions into the objective function. However, if the solution space is too large, this search method may be time consuming. In order to address this problem, this study incorporated the Taguchi method into the solution space search process of the optimization method, and used the characteristics of the Taguchi method to sequence the effects of the variation of decision variables on the system. Based on the level of effect, this study determined the impact factor of decision variables and the optimal solution for the model. The integration of the Taguchi method and the solution optimization method successfully obtained the optimal solution of the optimization problem, while significantly reducing the solution computing time and enhancing the river water quality. The results suggested that the basin with the greatest water quality improvement effectiveness is the Dahan River. Under the optimal strategy of this study, the severe pollution length was reduced from 18 km to 5 km. PMID:24739765

Yang, Tsung-Ming; Hsu, Nien-Sheng; Chiu, Chih-Chiang; Wang, Hsin-Ju

2014-04-01

208

Experimental characterisation of a novel viscoelastic rectifier design  

PubMed Central

A planar microfluidic system with contractions and obstacles is characterized in terms of anisotropic flow resistance due to viscoelastic effects. The working mechanism is illustrated using streak photography, while the diodicity performance is quantified by pressure drop measurements. The point of maximum performance is found to occur at relatively low elasticity levels, with diodicity around 3.5. Based on a previously published numerical work [Ejlebjerg et al., Appl. Phys. Lett. 100, 234102 (2012)], 2D simulations of the FENE-CR differential constitutive model are also presented, but limited reproducibility and uncertainties of the experimental data prevent a direct comparison at low elasticity, where the flow is essentially two-dimensional. PMID:24324532

Ejlebjerg Jensen, Kristian; Szabo, Peter; Okkels, Fridolin; Alves, M. A.

2012-01-01

209

A Modified Experimental Hut Design for Studying Responses of Disease-Transmitting Mosquitoes to Indoor Interventions: The Ifakara Experimental Huts  

PubMed Central

Differences between individual human houses can confound results of studies aimed at evaluating indoor vector control interventions such as insecticide treated nets (ITNs) and indoor residual insecticide spraying (IRS). Specially designed and standardised experimental huts have historically provided a solution to this challenge, with an added advantage that they can be fitted with special interception traps to sample entering or exiting mosquitoes. However, many of these experimental hut designs have a number of limitations, for example: 1) inability to sample mosquitoes on all sides of huts, 2) increased likelihood of live mosquitoes flying out of the huts, leaving mainly dead ones, 3) difficulties of cleaning the huts when a new insecticide is to be tested, and 4) the generally small size of the experimental huts, which can misrepresent actual local house sizes or airflow dynamics in the local houses. Here, we describe a modified experimental hut design - The Ifakara Experimental Huts- and explain how these huts can be used to more realistically monitor behavioural and physiological responses of wild, free-flying disease-transmitting mosquitoes, including the African malaria vectors of the species complexes Anopheles gambiae and Anopheles funestus, to indoor vector control-technologies including ITNs and IRS. Important characteristics of the Ifakara experimental huts include: 1) interception traps fitted onto eave spaces and windows, 2) use of eave baffles (panels that direct mosquito movement) to control exit of live mosquitoes through the eave spaces, 3) use of replaceable wall panels and ceilings, which allow safe insecticide disposal and reuse of the huts to test different insecticides in successive periods, 4) the kit format of the huts allowing portability and 5) an improved suite of entomological procedures to maximise data quality. PMID:22347415

Okumu, Fredros O.; Moore, Jason; Mbeyela, Edgar; Sherlock, Mark; Sangusangu, Robert; Ligamba, Godfrey; Russell, Tanya; Moore, Sarah J.

2012-01-01

210

Experimental design and quality assurance: in situ fluorescence instrumentation  

USGS Publications Warehouse

Both instrument design and capabilities of fluorescence spectroscopy have greatly advanced over the last several decades. Advancements include solid-state excitation sources, integration of fiber optic technology, highly sensitive multichannel detectors, rapid-scan monochromators, sensitive spectral correction techniques, and improve data manipulation software (Christian et al., 1981, Lochmuller and Saavedra, 1986; Cabniss and Shuman, 1987; Lakowicz, 2006; Hudson et al., 2007). The cumulative effect of these improvements have pushed the limits and expanded the application of fluorescence techniques to numerous scientific research fields. One of the more powerful advancements is the ability to obtain in situ fluorescence measurements of natural waters (Moore, 1994). The development of submersible fluorescence instruments has been made possible by component miniaturization and power reduction including advances in light sources technologies (light-emitting diodes, xenon lamps, ultraviolet [UV] lasers) and the compatible integration of new optical instruments with various sampling platforms (Twardowski et at., 2005 and references therein). The development of robust field sensors skirt the need for cumbersome and or time-consuming filtration techniques, the potential artifacts associated with sample storage, and coarse sampling designs by increasing spatiotemporal resolution (Chen, 1999; Robinson and Glenn, 1999). The ability to obtain rapid, high-quality, highly sensitive measurements over steep gradients has revolutionized investigations of dissolved organic matter (DOM) optical properties, thereby enabling researchers to address novel biogeochemical questions regarding colored or chromophoric DOM (CDOM). This chapter is dedicated to the origin, design, calibration, and use of in situ field fluorometers. It will serve as a review of considerations to be accounted for during the operation of fluorescence field sensors and call attention to areas of concern when making this type of measurement. Attention is also given to ways in which in-water fluorescence measurements have revolutionized biogeochemical studies of CDOM and how those measurements can be used in conjunction with remotely sense satellite data to understand better the biogeochemistry of DOM in aquatic environments.

Conmy, Robyn N.; Del Castillo, Carlos E.; Downing, Bryan D.; Chen, Robert F.

2014-01-01

211

Design and construction of an experimental mass spectrometer  

E-print Network

. Sub? sequently, mass spectrometers of the Bleakney - Hippie type have been built by two groups. Prom Oak Ridge have come re- 11 12 ports by Horton, by Monk, Horton and Graves, by Monk, Steele, and Burkhart,1 ^and by Monk and Werner1 -^ of suc...? cessful instruments and of design considerations. Mariner 1^and Bleakney have constructed a large instrument of high resolving power as a sequal to the first work of Bleakney and Hippie. Horton?S has proposed the name trochotron for instruments...

Wall, Robert F.

2013-10-04

212

Apollo-Soyuz pamphlet no. 4: Gravitational field. [experimental design  

NASA Technical Reports Server (NTRS)

Two Apollo Soyuz experiments designed to detect gravity anomalies from spacecraft motion are described. The geodynamics experiment (MA-128) measured large-scale gravity anomalies by detecting small accelerations of Apollo in the 222 km orbit, using Doppler tracking from the ATS-6 satellite. Experiment MA-089 measured 300 km anomalies on the earth's surface by detecting minute changes in the separation between Apollo and the docking module. Topics discussed in relation to these experiments include the Doppler effect, gravimeters, and the discovery of mascons on the moon.

Page, L. W.; From, T. P.

1977-01-01

213

The ISR Asymmetrical Capacitor Thruster: Experimental Results and Improved Designs  

NASA Technical Reports Server (NTRS)

A variety of Asymmetrical Capacitor Thrusters has been built and tested at the Institute for Scientific Research (ISR). The thrust produced for various voltages has been measured, along with the current flowing, both between the plates and to ground through the air (or other gas). VHF radiation due to Trichel pulses has been measured and correlated over short time scales to the current flowing through the capacitor. A series of designs were tested, which were increasingly efficient. Sharp features on the leading capacitor surface (e.g., a disk) were found to increase the thrust. Surprisingly, combining that with sharp wires on the trailing edge of the device produced the largest thrust. Tests were performed for both polarizations of the applied voltage, and for grounding one or the other capacitor plate. In general (but not always) it was found that the direction of the thrust depended on the asymmetry of the capacitor rather than on the polarization of the voltage. While no force was measured in a vacuum, some suggested design changes are given for operation in reduced pressures.

Canning, Francis X.; Cole, John; Campbell, Jonathan; Winet, Edwin

2004-01-01

214

Design and experimental tests of a novel neutron spin analyzer for wide angle spin echo spectrometers  

SciTech Connect

This paper describes the design and experimental tests of a novel neutron spin analyzer optimized for wide angle spin echo spectrometers. The new design is based on nonremanent magnetic supermirrors, which are magnetized by vertical magnetic fields created by NdFeB high field permanent magnets. The solution presented here gives stable performance at moderate costs in contrast to designs invoking remanent supermirrors. In the experimental part of this paper we demonstrate that the new design performs well in terms of polarization, transmission, and that high quality neutron spin echo spectra can be measured.

Fouquet, Peter; Farago, Bela; Andersen, Ken H.; Bentley, Phillip M.; Pastrello, Gilles; Sutton, Iain; Thaveron, Eric; Thomas, Frederic [Institut Laue-Langevin, BP 156, F-38042 Grenoble Cedex 9 (France); Moskvin, Evgeny [Helmholtzzentrum Berlin, Glienicker Strasse 100, D-14109 Berlin (Germany); Pappas, Catherine [Helmholtzzentrum Berlin, Glienicker Strasse 100, D-14109 Berlin (Germany); Faculty of Applied Sciences, Delft University of Technology, Mekelweg 15, 2629 JB Delft (Netherlands)

2009-09-15

215

Expanded microchannel heat exchanger: design, fabrication and preliminary experimental test  

E-print Network

This paper first reviews non-traditional heat exchanger geometry, laser welding, practical issues with microchannel heat exchangers, and high effectiveness heat exchangers. Existing microchannel heat exchangers have low material costs, but high manufacturing costs. This paper presents a new expanded microchannel heat exchanger design and accompanying continuous manufacturing technique for potential low-cost production. Polymer heat exchangers have the potential for high effectiveness. The paper discusses one possible joining method - a new type of laser welding named "forward conduction welding," used to fabricate the prototype. The expanded heat exchanger has the potential to have counter-flow, cross-flow, or parallel-flow configurations, be used for all types of fluids, and be made of polymers, metals, or polymer-ceramic precursors. The cost and ineffectiveness reduction may be an order of magnitude or more, saving a large fraction of primary energy. The measured effectiveness of the prototype with 28 micro...

Denkenberger, David C; Pearce, Joshua M; Zhai, John; 10.1177/0957650912442781

2012-01-01

216

PhET Teacher Activities: Experimental Design with Forces  

NSDL National Science Digital Library

This middle school lesson plan blends a classroom experiment with the interactive PhET simulation Masses and Springs. Students design and conduct an experiment to test their predictions about the behavior of springs with masses attached. The simulation is used to explore kinetic and potential energy of spring motion and to visualize how the spring moves on different planets with varied gravitational constants. The lesson provides extensive background information for both educators and learners along with scripted teacher discussion. The simulation required to complete this activity is available from PhET at: Masses & Springs Simulation. This lesson is part of the PhET (Physics Education Technology Project), a large collection of free interactive science simulations.

Texas, Uteach -.

217

Design and experimental evaluation of flexible manipulator control algorithms  

SciTech Connect

Within the Environmental Restoration and Waste Management Program of the US Department of Energy, the remediation of single-shell radioactive waste storage tanks is one of the areas that challenge state-of-the-art equipment and methods. The use of long-reach manipulators is being seriously considered for this task. Because of high payload capacity and high length-to-cross-section ratio requirements, these long-reach manipulator systems are expected to use hydraulic actuators and to exhibit significant structural flexibility. The controller has been designed to compensate for the hydraulic actuator dynamics by using a load-compensated velocity feedforward loop and to increase the bandwidth by using an inner pressure feedback loop. Shaping filter techniques have been applied as feedforward controllers to avoid structural vibrations during operation. Various types of shaping filter methods have been investigated. Among them, a new approach, referred to as a ``feedforward simulation filter`` that uses embedded simulation, has been presented.

Kwon, D.S.; Hwang, D.H.; Babcock, S.M.; Kress, R.L. [Oak Ridge National Lab., TN (United States). Robotics and Process Systems Div.; Lew, J.Y.; Evans, M.S. [Pacific Northwest Lab., Richland, WA (United States)

1995-04-01

218

Optimization of experimental designs and model parameters exemplified by sedimentation in salt marshes  

NASA Astrophysics Data System (ADS)

The weighted least squares estimator for model parameters was presented together with its asymptotic properties. A popular approach to optimize experimental designs called local optimal experimental designs was described together with a lesser known approach which takes into account a potential nonlinearity of the model parameters. These two approaches were combined with two different methods to solve their underlying discrete optimization problem. All presented methods were implemented in an open source MATLAB toolbox called the Optimal Experimental Design Toolbox whose structure and handling was described. In numerical experiments, the model parameters and experimental design were optimized using this toolbox. Two models for sediment concentration in seawater of different complexity served as application example. The advantages and disadvantages of the different approaches were compared, and an evaluation of the approaches was performed.

Reimer, J.; Schürch, M.; Slawig, T.

2014-09-01

219

Experimental concept and design of DarkLight, a search for a heavy photon  

SciTech Connect

This talk gives an overview of the DarkLight experimental concept: a search for a heavy photon A′ in the 10-90 MeV/c 2 mass range. After briefly describing the theoretical motivation, the talk focuses on the experimental concept and design. Topics include operation using a half-megawatt, 100 MeV electron beam at the Jefferson Lab FEL, detector design and performance, and expected backgrounds estimated from beam tests and Monte Carlo simulations.

Cowan, Ray F. [MIT

2013-11-01

220

Experimental concept and design of DarkLight, a search for a heavy photon  

SciTech Connect

This talk gives an overview of the DarkLight experimental concept: a search for a heavy photon A? in the 10-90 MeV/c{sup 2} mass range. After briefly describing the theoretical motivation, the talk focuses on the experimental concept and design. Topics include operation using a half-megawatt, 100 MeV electron beam at the Jefferson Lab FEL, detector design and performance, and expected backgrounds estimated from beam tests and Monte Carlo simulations.

Cowan, Ray F. [Laboratory for Nuclear Science, M.I.T., 77 Massachusetts Avenue, Cambridge, MA 02139 (United States); Collaboration: DarkLight Collaboration

2013-11-07

221

Experimental concept and design of DarkLight, a search for a heavy photon  

NASA Astrophysics Data System (ADS)

This talk gives an overview of the DarkLight experimental concept: a search for a heavy photon A' in the 10-90 MeV/c2 mass range. After briefly describing the theoretical motivation, the talk focuses on the experimental concept and design. Topics include operation using a half-megawatt, 100 MeV electron beam at the Jefferson Lab FEL, detector design and performance, and expected backgrounds estimated from beam tests and Monte Carlo simulations.

Cowan, Ray F.; DarkLight Collaboration

2013-11-01

222

Automatic Identification of Quasi-Experimental Designs for Discovering Causal Knowledge  

E-print Network

,afast,btaylor,maier}@cs.umass.edu ABSTRACT Researchers in the social and behavioral sciences routinely rely on quasi-experimental designs are a staple of research in the social and behavioral sciences, economics, and medicine. A quasi- experimental as sociology, medicine, and marketing to draw reliable inferences about causal dependencies from non

Jensen, David

223

Design and Validation of a Virtual Environment for Experimentation inside the Small Intestine  

E-print Network

Design and Validation of a Virtual Environment for Experimentation inside the Small Intestine Liang algorithm inside small intestine faces a lot of difficulties since any experimentation on the human being small intestine would facilitate the process of verifying the performance of existing algorithms without

Pahlavan, Kaveh

224

A nonlinear controller for pneumatic servo systems: Design and experimental tests  

E-print Network

1 A nonlinear controller for pneumatic servo systems: Design and experimental tests S. Riachy and M. Ghanes Abstract--This paper is dedicated to the problem of pneumatic cylinder control without pressure are illustrated against an experimental setup consisting of a pneumatic cylinder controlled by dSPACE dS1103

Paris-Sud XI, Université de

225

Protein design with a comprehensive statistical energy function and boosted by experimental selection for foldability.  

PubMed

The de novo design of amino acid sequences to fold into desired structures is a way to reach a more thorough understanding of how amino acid sequences encode protein structures and to supply methods for protein engineering. Notwithstanding significant breakthroughs, there are noteworthy limitations in current computational protein design. To overcome them needs computational models to complement current ones and experimental tools to provide extensive feedbacks to theory. Here we develop a comprehensive statistical energy function for protein design with a new general strategy and verify that it can complement and rival current well-established models. We establish that an experimental approach can be used to efficiently assess or improve the foldability of designed proteins. We report four de novo proteins for different targets, all experimentally verified to be well-folded, solved solution structures for two being in excellent agreement with respective design targets. PMID:25345468

Xiong, Peng; Wang, Meng; Zhou, Xiaoqun; Zhang, Tongchuan; Zhang, Jiahai; Chen, Quan; Liu, Haiyan

2014-01-01

226

Visions of visualization aids: Design philosophy and experimental results  

NASA Technical Reports Server (NTRS)

Aids for the visualization of high-dimensional scientific or other data must be designed. Simply casting multidimensional data into a two- or three-dimensional spatial metaphor does not guarantee that the presentation will provide insight or parsimonious description of the phenomena underlying the data. Indeed, the communication of the essential meaning of some multidimensional data may be obscured by presentation in a spatially distributed format. Useful visualization is generally based on pre-existing theoretical beliefs concerning the underlying phenomena which guide selection and formatting of the plotted variables. Two examples from chaotic dynamics are used to illustrate how a visulaization may be an aid to insight. Two examples of displays to aid spatial maneuvering are described. The first, a perspective format for a commercial air traffic display, illustrates how geometric distortion may be introduced to insure that an operator can understand a depicted three-dimensional situation. The second, a display for planning small spacecraft maneuvers, illustrates how the complex counterintuitive character of orbital maneuvering may be made more tractable by removing higher-order nonlinear control dynamics, and allowing independent satisfaction of velocity and plume impingement constraints on orbital changes.

Ellis, Stephen R.

1990-01-01

227

Strong Lens Time Delay Challenge. I. Experimental Design  

NASA Astrophysics Data System (ADS)

The time delays between point-like images in gravitational lens systems can be used to measure cosmological parameters. The number of lenses with measured time delays is growing rapidly; the upcoming Large Synoptic Survey Telescope (LSST) will monitor ~103 strongly lensed quasars. In an effort to assess the present capabilities of the community, to accurately measure the time delays, and to provide input to dedicated monitoring campaigns and future LSST cosmology feasibility studies, we have invited the community to take part in a "Time Delay Challenge" (TDC). The challenge is organized as a set of "ladders," each containing a group of simulated data sets to be analyzed blindly by participating teams. Each rung on a ladder consists of a set of realistic mock observed lensed quasar light curves, with the rungs' data sets increasing in complexity and realism. The initial challenge described here has two ladders, TDC0 and TDC1. TDC0 has a small number of data sets, and is designed to be used as a practice set by the participating teams. The (non-mandatory) deadline for completion of TDC0 was the TDC1 launch date, 2013 December 1. The TDC1 deadline was 2014 July 1. Here we give an overview of the challenge, we introduce a set of metrics that will be used to quantify the goodness of fit, efficiency, precision, and accuracy of the algorithms, and we present the results of TDC0. Thirteen teams participated in TDC0 using 47 different methods. Seven of those teams qualified for TDC1, which is described in the companion paper.

Dobler, Gregory; Fassnacht, Christopher D.; Treu, Tommaso; Marshall, Phil; Liao, Kai; Hojjati, Alireza; Linder, Eric; Rumbaugh, Nicholas

2015-02-01

228

Optical metamaterials: Design, simulation and feedback from experimental characterization  

NASA Astrophysics Data System (ADS)

Artificially structured materials (metamaterials) demonstrating negative index of refraction have opened an entire area of research. Metamaterials are not limited to just negative index metamaterials, but could be extended to artificial magnetism, chirality, etc. Such materials extend the material properties, to beyond what is available in nature. This enables us to control and manipulate light in an unprecedented manner and creates an immense potential for applications. In this work, simulations tools were developed for the study and design of metamaterials. These tools were based on 3D Finite Difference Time Domain (FDTD) method and Spatial Harmonic Analysis (SHA). In addition to this, a commercial tool based on Finite Element Method was also used. The first negative index material at the optical range was demonstrated, which showed a refractive index of around --0.3 at the telecom wavelength of 1.5 mum. This was followed by the demonstration of a double negative material at the lowest wavelength till date. It showed a refractive index of --0.8 at a wavelength of 725 nm. The negative index material at the shortest wavelength was demonstrated at a wavelength of 710nm. It showed a refractive index of --0.6 at a wavelength of 710 nm. Structures with artificial negative magnetism were also demonstrated across the entire visible range up to a wavelength of 490 nm. Rigorous study was performed on the effect of roughness and size effects on the performance of the nanoscale structures that were used in the metamaterial prototypes. It was concluded that roughness decreases the quality factor of the resonances that are vital for the novel properties. Roughness affects only parts of the spectrum that are close to a resonance. The size effect increases the losses in the metal that makes up the structure and consequently decreases the quality factor of the resonances. Unlike roughness, the size effect does not show a wavelength dependence based on resonances. The parallel 3D FDTD solver was used to numerically study the local field response in semicontinuous metal films (SMFs). These solutions provide insight into the nature of the local field enhancements in SMFs.

Chettiar, Uday Krishnaswamy

229

Experimental Design for Combinatorial and High Throughput 239 Materials Development, Edited by James N. Cawse.  

E-print Network

binding constant. If a Monte Carlo protocol for library design is to be valid, it must possess several by James N. Cawse. ISBN 0-471-20343-2 © 2003 John Wiley & Sons, Inc. CHAPTER 12 THE MONTE CARLO APPROACH and experimental variable spaces, is central to the design of high-through- put experiments. There is a striking

Deem, Michael W.

230

Micro Position Control of a Designed 3-PRR Compliant Mechanism Using Experimental Models  

E-print Network

Micro Position Control of a Designed 3-PRR Compliant Mechanism Using Experimental Models Merve Acer stage based on 3-PRR kinematic structure is designed to be used as a planar micro positioner, which is the accuracy of the dual laser position sensor. Keywords-- compliant mechanism, micro motion

Yanikoglu, Berrin

231

A Sino-Finnish Initiative for Experimental Teaching Practices Using the Design Factory Pedagogical Platform  

ERIC Educational Resources Information Center

The paper presents a Sino-Finnish teaching initiative, including the design and experiences of a series of pedagogical workshops implemented at the Aalto-Tongji Design Factory (DF), Shanghai, China, and the experimentation plans collected from the 54 attending professors and teachers. The workshops aimed to encourage trying out interdisciplinary…

Björklund, Tua A.; Nordström, Katrina M.; Clavert, Maria

2013-01-01

232

Design and analysis of a high pressure and high temperature sulfuric acid experimental system  

Microsoft Academic Search

We discuss the design and analysis of a small scale sulfuric acid experimental system that can simulate a part of the hydrogen production module. Because nuclear hydrogen coupled components such as a SO3 decomposer and a sulfuric acid evaporator should be tested under high pressure and high temperature operating conditions, we developed the sulfuric acid loop to satisfy design specifications

Sung-Deok Hong; Chan-Soo Kim; Yong-Wan Kim; Dong-Un Seo; Goon-Cherl Park

233

Design and experimental validation of a compact quadrifilar helix antenna in VHF band  

Microsoft Academic Search

A compact quadrifilar helix antenna is presented in the VHF band. The design and experimental validation on a low-cost realization are detailed in this paper. This design could be used on the telemetry link for the SVOM satellite project. Compared to the reference antenna, a significant height reduction of 48% is demonstrated. The measurement and simulation results reveal the capability

Nelson J. G. Fonseca; Alexandru Takacs; Hervé Aubert; Xavier Dollat

2009-01-01

234

Experimental design and evaluation of Networked Traveler field tests of safety applications in California  

Microsoft Academic Search

This paper describes the experimental design for the field tests of safety applications within the scope of Networked Traveler Project currently being conducted in California, which is part of the US Department of Transportation (USDOT) and California DOT-sponsored Safe-Trip 21 Initiative. The safety applications are designed to provide drivers with alerts of situational awareness in highway driving scenarios. The objectives

Ching-Yao Chan; Christian Manasseh; Shahram Rezaei

2010-01-01

235

Assessing the Effectiveness of a Computer Simulation for Teaching Ecological Experimental Design  

ERIC Educational Resources Information Center

Designing manipulative ecological experiments is a complex and time-consuming process that is problematic to teach in traditional undergraduate classes. This study investigates the effectiveness of using a computer simulation--the Virtual Rocky Shore (VRS)--to facilitate rapid, student-centred learning of experimental design. We gave a series of…

Stafford, Richard; Goodenough, Anne E.; Davies, Mark S.

2010-01-01

236

Scaffolding a Complex Task of Experimental Design in Chemistry with a Computer Environment  

ERIC Educational Resources Information Center

When solving a scientific problem through experimentation, students may have the responsibility to design the experiment. When students work in a conventional condition, with paper and pencil, the designed procedures stay at a very general level. There is a need for additional scaffolds to help the students perform this complex task. We propose a…

Girault, Isabelle; d'Ham, Cédric

2014-01-01

237

Development and Validation of a Rubric for Diagnosing Students' Experimental Design Knowledge and Difficulties  

ERIC Educational Resources Information Center

It is essential to teach students about experimental design, as this facilitates their deeper understanding of how most biological knowledge was generated and gives them tools to perform their own investigations. Despite the importance of this area, surprisingly little is known about what students actually learn from designing biological…

Dasgupta, Annwesa P.; Anderson, Trevor R.; Pelaez, Nancy

2014-01-01

238

Observational Studies Randomized Controlled Experiments Principles of Experimental Design Random Samples Case Study Producing Data  

E-print Network

Samples Case Study Topic 4 Producing Data Formal Statistical Procedures 1 / 16 #12;Observational Studies Randomized Controlled Experiments Principles of Experimental Design Random Samples Case Study Outline Setting a Design Random Samples Case Study 2 / 16 #12;Observational Studies Randomized Controlled

Watkins, Joseph C.

239

Exploiting Distance Technology to Foster Experimental Design as a Neglected Learning Objective in Labwork in Chemistry  

ERIC Educational Resources Information Center

This paper deals with the design process of a remote laboratory for labwork in chemistry. In particular, it focuses on the mutual dependency of theoretical conjectures about learning in the experimental sciences and technological opportunities in creating learning environments. The design process involves a detailed analysis of the expert task and…

d'Ham, Cedric; de Vries, Erica; Girault, Isabelle; Marzin, Patricia

2004-01-01

240

Experimental Control and Threats to Internal Validity of Concurrent and Nonconcurrent Multiple Baseline Designs  

ERIC Educational Resources Information Center

Single-case research designs are often applied within school psychology. This article provides a critical review of the scientific merit of both concurrent and nonconcurrent multiple baseline (MB) designs, relative to their capacity to assess threats of internal validity and establish experimental control. Distinctions are established between AB…

Christ, Theodore J.

2007-01-01

241

Design and experimental study of high-speed low-flow-rate centrifugal compressors. Technical paper  

Microsoft Academic Search

This paper describes a design and experimental effort to develop small centrifugal compressors for aircraft air cycle cooling systems and small vapor compression refrigeration systems (20--100 tons). Efficiency improvements at 25% are desired over current designs. Although centrifugal compressors possess excellent performance at high flow rates, low-flow-rate compressors do not have acceptable performance when designed using current approaches. The new

F. Gui; T. R. Reinarts; R. P. Scaringe; J. M. Gottschlich

1995-01-01

242

A Computational/Experimental Study of Two Optimized Supersonic Transport Designs and the Reference H Baseline  

NASA Technical Reports Server (NTRS)

Two supersonic transport configurations designed by use of non-linear aerodynamic optimization methods are compared with a linearly designed baseline configuration. One optimized configuration, designated Ames 7-04, was designed at NASA Ames Research Center using an Euler flow solver, and the other, designated Boeing W27, was designed at Boeing using a full-potential method. The two optimized configurations and the baseline were tested in the NASA Langley Unitary Plan Supersonic Wind Tunnel to evaluate the non-linear design optimization methodologies. In addition, the experimental results are compared with computational predictions for each of the three configurations from the Enter flow solver, AIRPLANE. The computational and experimental results both indicate moderate to substantial performance gains for the optimized configurations over the baseline configuration. The computed performance changes with and without diverters and nacelles were in excellent agreement with experiment for all three models. Comparisons of the computational and experimental cruise drag increments for the optimized configurations relative to the baseline show excellent agreement for the model designed by the Euler method, but poorer comparisons were found for the configuration designed by the full-potential code.

Cliff, Susan E.; Baker, Timothy J.; Hicks, Raymond M.; Reuther, James J.

1999-01-01

243

Optimal experimental designs for dose-response studies with continuous endpoints.  

PubMed

In most areas of clinical and preclinical research, the required sample size determines the costs and effort for any project, and thus, optimizing sample size is of primary importance. An experimental design of dose-response studies is determined by the number and choice of dose levels as well as the allocation of sample size to each level. The experimental design of toxicological studies tends to be motivated by convention. Statistical optimal design theory, however, allows the setting of experimental conditions (dose levels, measurement times, etc.) in a way which minimizes the number of required measurements and subjects to obtain the desired precision of the results. While the general theory is well established, the mathematical complexity of the problem so far prevents widespread use of these techniques in practical studies. The paper explains the concepts of statistical optimal design theory with a minimum of mathematical terminology and uses these concepts to generate concrete usable D-optimal experimental designs for dose-response studies on the basis of three common dose-response functions in toxicology: log-logistic, log-normal and Weibull functions with four parameters each. The resulting designs usually require control plus only three dose levels and are quite intuitively plausible. The optimal designs are compared to traditional designs such as the typical setup of cytotoxicity studies for 96-well plates. As the optimal design depends on prior estimates of the dose-response function parameters, it is shown what loss of efficiency occurs if the parameters for design determination are misspecified, and how Bayes optimal designs can improve the situation. PMID:25155192

Holland-Letz, Tim; Kopp-Schneider, Annette

2014-08-26

244

Unique considerations in the design and experimental evaluation of tailored wings with elastically produced chordwise camber  

NASA Technical Reports Server (NTRS)

Some of the unique considerations that are associated with the design and experimental evaluation of chordwise deformable wing structures are addressed. Since chordwise elastic camber deformations are desired and must be free to develop, traditional rib concepts and experimental methodology cannot be used. New rib design concepts are presented and discussed. An experimental methodology based upon the use of a flexible sling support and load application system has been created and utilized to evaluate a model box beam experimentally. Experimental data correlate extremely well with design analysis predictions based upon a beam model for the global properties of camber compliance and spanwise bending compliance. Local strain measurements exhibit trends in agreement with intuition and theory but depart slightly from theoretical perfection based upon beam-like behavior alone. It is conjectured that some additional refinement of experimental technique is needed to explain or eliminate these (minor) departures from asymmetric behavior of upper and lower box cover strains. Overall, a solid basis for the design of box structures based upon the bending method of elastic camber production has been confirmed by the experiments.

Rehfield, Lawrence W.; Zischka, Peter J.; Fentress, Michael L.; Chang, Stephen

1992-01-01

245

Thermal-hydraulic design issues and analysis for the ITER (International Thermonuclear Experimental Reactor) divertor  

SciTech Connect

Critical Heat Flux (CHF), also called burnout, is one of the major design limits for water-cooled divertors in tokamaks. Another important design issue is the correct thermal modeling of the divertor plate geometry where heat is applied to only one side of the plate and highly subcooled flow boiling in internal passages is used for heat removal. This paper discusses analytical techniques developed to address these design issues, and the experimental evidence gathered in support of the approach. Typical water-cooled divertor designs for the International Thermonuclear Experimental Reactor (ITER) are analyzed, and design margins estimated. Peaking of the heat flux at the tube-water boundary is shown to be an important issue, and design concerns which could lead to imposing large design safety margins are identified. The use of flow enhancement techniques such as internal twisted tapes and fins are discussed, and some estimates of the gains in the design margin are presented. Finally, unresolved issues and concerns regarding hydraulic design of divertors are summarized, and some experiments which could help the ITER final design process identified. 23 refs., 10 figs.

Koski, J.A.; Watson, R.D. (Sandia National Labs., Albuquerque, NM (USA)); Hassanien, A.M. (Argonne National Lab., IL (USA)); Goranson, P.L. (Oak Ridge National Lab., TN (USA). Fusion Engineering Design Center); Salmonson, J.C. (EG and G Energy Measurements Group, Inc., Albuquerque, NM (USA). Special Projects)

1990-01-01

246

Analytical and experimental performance of optimal controller designs for a supersonic inlet  

NASA Technical Reports Server (NTRS)

The techniques of modern optimal control theory were applied to the design of a control system for a supersonic inlet. The inlet control problem was approached as a linear stochastic optimal control problem using as the performance index the expected frequency of unstarts. The details of the formulation of the stochastic inlet control problem are presented. The computational procedures required to obtain optimal controller designs are discussed, and the analytically predicted performance of controllers designed for several different inlet conditions is tabulated. The experimental implementation of the optimal control laws is described, and the experimental results obtained in a supersonic wind tunnel are presented. The control laws were implemented with analog and digital computers. Comparisons are made between the experimental and analytically predicted performance results. Comparisons are also made between the results obtained with continuous analog computer controllers and discrete digital computer versions.

Zeller, J. R.; Lehtinen, B.; Geyser, L. C.; Batterton, P. G.

1973-01-01

247

Efficient experimental design and analysis of real-time PCR assays  

PubMed Central

Real-time polymerase chain reaction (qPCR) is currently the standard for gene quantification studies and has been extensively used in large-scale basic and clinical research. The operational costs and technical errors can become a significant issue due to the large number of sample reactions. In this paper, we present an experimental design strategy and an analysis procedure that are more efficient requiring fewer sample reactions than the traditional approach. We verified mathematically and experimentally the new design on a well-characterized model, to evaluate the gene expression levels of CACNA1C and CACNA1G in hypertrophic ventricular myocytes induced by phenylephrine treatment. PMID:23510941

Hui, Kwokyin; Feng, Zhong-Ping

2013-01-01

248

A comparison of the calculated and experimental off-design performance of a radial flow turbine  

NASA Technical Reports Server (NTRS)

Off design aerodynamic performance of the solid version of a cooled radial inflow turbine is analyzed. Rotor surface static pressure data and other performance parameters were obtained experimentally. Overall stage performance and turbine blade surface static to inlet total pressure ratios were calculated by using a quasi-three dimensional inviscid code. The off design prediction capability of this code for radial inflow turbines shows accurate static pressure prediction. Solutions show a difference of 3 to 5 points between the experimentally obtained efficiencies and the calculated values.

Tirres, Lizet

1991-01-01

249

Design of the Sulfate Regional Experiment (SURE). Volume II. Proposed experimental design. Final report  

Microsoft Academic Search

This planning study - Design of the Sulfate Regional Experiment (SURE) - was conducted on project RP 485 to determine ways of predicting the impact of emissions from fossil fuel combustion by the electric utilities industry on ambient sulfate, nitrate and related concentrations in a large region downward of groups of major sources. The end goal of the analysis and

G. M. Hidy; P. K. Mueller; E. Y. Tong; J. R. Mahoney; N. E. Gaut

1976-01-01

250

The use of grey-based Taguchi methods to determine submerged arc welding process parameters in hardfacing  

Microsoft Academic Search

In this paper, the use of grey-based Taguchi methods for the optimization of the submerged arc welding (SAW) process parameters in hardfacing with considerations of multiple weld qualities is reported. In this new approach, the grey relational analysis is adopted to solve the SAW process with multiple weld qualities. A grey relational grade obtained from the grey relational analysis is

Y. S. Tarng; S. C. Juang; C. H. Chang

2002-01-01

251

Design and Experimental Validation of a Robust Control Method for a Hybrid  

E-print Network

Design and Experimental Validation of a Robust Control Method for a Hybrid Fuel Cell Power Generation System David Hermlndez-Torres, Delphine Riu Grenoble Electrical Engineering Laboratory 38400 Saint of electrical energy using a pair of electrodes, an electrolyte aod a catalyst. FC's are attractive because

Paris-Sud XI, Université de

252

Achievement of optimal aluminum flake orientation by the use of special cubic experimental design  

Microsoft Academic Search

In the present investigation, attempts were made to predict the effect of variations in a coating's composition on aluminum flake orientation by means of a special cubic experimental design. The results showed that there seems to be a critical concentration of aluminum flake, above which the surface parallel orientations of these flakes as well as the mechanical properties of the

Ali Karbasi; Siamak Moradian; Nargess Tahmassebi; Payam Ghodsi

2006-01-01

253

Feasibility study and optimal design of an experimental bench for identification of liquids thermal diffusivity  

E-print Network

Feasibility study and optimal design of an experimental bench for identification of liquids thermal. In this context, if identification of thermal diffusivity of liquid is a crucial requirement to develop a reliable]-[4]. These are illustrated by many applications and can include, for example identification of thermal conductivity tensor

Paris-Sud XI, Université de

254

The Impact of the Hawthorne Effect in Experimental Designs in Educational Research. Final Report.  

ERIC Educational Resources Information Center

Project objectives included (1) establishing a body of knowledge concerning the role of the Hawthorne effect in experimental designs in educational research, (2) assessing the influence of the Hawthorne effect on educational experiments conducted under varying conditions of control, (3) identifying the major components comprising the effect, and…

Cook, Desmond L.

255

Whither Instructional Design and Teacher Training? The Need for Experimental Research  

ERIC Educational Resources Information Center

This article takes a contrarian position: an "instructional design" or "teacher training" model, because of the sheer number of its interconnected parameters, is too complex to assess or to compare with other models. Models may not be the way to go just yet. This article recommends instead prior experimental research on limited…

Gropper, George L.

2015-01-01

256

Quiet Clean Short-haul Experimental Engine (QCSEE) Over The Wing (OTW) design report  

NASA Technical Reports Server (NTRS)

The design, fabrication, and testing of two experimental high bypass geared turbofan engines and propulsion systems for short haul passenger aircraft are described. The propulsion technology required for future externally blown flap aircraft with engines located both under the wing and over the wing is demonstrated. Composite structures and digital engine controls are among the topics included.

1977-01-01

257

OPTIMIZING THE PRECISION OF TOXICITY THRESHOLD ESTIMATION USING A TWO-STAGE EXPERIMENTAL DESIGN  

EPA Science Inventory

An important consideration for risk assessment is the existence of a threshold, i.e., the highest toxicant dose where the response is not distinguishable from background. We have developed methodology for finding an experimental design that optimizes the precision of threshold mo...

258

Insights From The Design, Construction And Operation Of An Experimental Stormwater Biofiltration System  

Microsoft Academic Search

Biofiltration systems are being installed on an ever-increasing scale, both for stormwater quality improvement and as a component of stormwater reuse systems. However, there is currently a general lack of knowledge regarding their design, implementation and performance. This paper reports on the issues encountered and lessons learnt during the installation and operation of an experimental biofiltration system. While the water

B. E. Hatt; J. Lewis; A. Deletic; T. D. Fletcher

259

Characterizing Variability in Smestad and Gratzel's Nanocrystalline Solar Cells: A Collaborative Learning Experience in Experimental Design  

ERIC Educational Resources Information Center

This article describes a collaborative learning experience in experimental design that closely approximates what practicing statisticians and researchers in applied science experience during consulting. Statistics majors worked with a teaching assistant from the chemistry department to conduct a series of experiments characterizing the variation…

Lawson, John; Aggarwal, Pankaj; Leininger, Thomas; Fairchild, Kenneth

2011-01-01

260

Design, Implementation, and Experimentation on Mobile Agent Security for Electronic Commerce  

E-print Network

Design, Implementation, and Experimentation on Mobile Agent Security for Electronic Commerce speci ed by users from di erent seller hosts in an electronic market. Security issues of the system out agents to di erent hosts in an electronic marketplace. The agents collect and report information

Lyu, Michael R.

261

A Course on Experimental Design for Different University Specialties: Experiences and Changes over a Decade  

ERIC Educational Resources Information Center

We analyse the origin and development of an Experimental Design course which has been taught in several faculties of the Universidad de la Republica and other institutions in Uruguay, over a 10-year period. At the end of the course, students were assessed by carrying out individual work projects on real-life problems, which was innovative for…

Martinez Luaces, Victor; Velazquez, Blanca; Dee, Valerie

2009-01-01

262

Return to Our Roots: Raising Radishes to Teach Experimental Design. Methods and Techniques.  

ERIC Educational Resources Information Center

Reviews research in teaching applied statistics. Concludes that students should analyze data from studies they have designed and conducted. Describes an activity in which students study germination and growth of radish seeds. Includes a table providing student instructions for both the experimental procedure and data analysis. (CFR)

Stallings, William M.

1993-01-01

263

LEARNING FROM DAM REMOVAL MONITORING: CHALLENGES TO SELECTING EXPERIMENTAL DESIGN AND ESTABLISHING SIGNIFICANCE OF OUTCOMES  

E-print Network

LEARNING FROM DAM REMOVAL MONITORING: CHALLENGES TO SELECTING EXPERIMENTAL DESIGN AND ESTABLISHING, California, USA ABSTRACT As the decommissioning of dams becomes a common restoration technique, decisions about dam removals must be based on sound predictions of expected outcomes. Results of past and ongoing

Tullos, Desiree

264

An Inventory for Appraising Experimental Research Designed for Introductory Research Methods Classes.  

ERIC Educational Resources Information Center

The development of the Evaluation Instrument for Experimental Research (EIFER), an inventory for appraising research quality, is described. The EIFER was specifically designed to aid students in introductory courses in educational and psychological research methods to evaluate published research reports. A survey conducted among specialists in…

Hsu, Yi-Ming; Scott, Owen

265

Xylanase production in solid state fermentation by Aspergillus niger mutant using statistical experimental designs  

Microsoft Academic Search

. The initial moisture content, cultivation time, inoculum size and concentration of basal medium were optimized in solid state fermentation (SSF) for the production of xylanase by an Aspergillus niger mutant using statistical experimental designs. The cultivation time and concentration of basal medium were the most important factors affecting xylanase activity. An inoculum size of 5쎹 spores\\/g, initial moisture content

Y. S. Park; S. W. Kang; J. S. Lee; S. I. Hong; S. W. Kim

2002-01-01

266

Digital learning material for experimental design and model building in molecular biology  

Microsoft Academic Search

Designing experimental approaches is a major cognitive skill in molecular biology research, and building models, including quantitative ones, is a cognitive skill which is rapidly gaining importance. Since molecular biology education at university level is aimed at educating future researchers, we consider it important that students already start developing these skills during their studies. In general, cognitive skills can be

T. Aegerter-Wilmsen

2005-01-01

267

Measuring plant dispersal: an introduction to field methods and experimental design  

Microsoft Academic Search

The measurement of plant dispersal is vital for understanding plant distribution and abundance at different scales. However, dispersal is difficult to measure and there is a lack of guidance for researchers new to the subject. In this paper we provide advice on methods for measuring dispersal in the field and approaches to experimental design. First, we encourage clear exposition of

James M. Bullock; Katriona Shea; Olav Skarpaas

2006-01-01

268

An experimental design for total container impact response modeling at extreme temperatures  

NASA Technical Reports Server (NTRS)

An experimental design (a drop test) was developed to test the effects of confinement upon cushions. The drop test produced consistent corner void cushion data from which mathematical models were developed. A mathematical relationship between temperature and drop height was found.

Kobler, V. P.; Wyskida, R. M.; Johannes, J. D.

1979-01-01

269

An evaluation of modified R -change effect size indices for single-subject experimental designs  

Microsoft Academic Search

The current study describes modification of change in R (?R ) indices used to describe a treatment's effect on the level and linear growth in outcome measures in single-subject experimental designs. A description of how to calculate each index, its standard error and associated test statistic is provided. A small simulation study was conducted to evaluate the Type I error

S. Natasha Beretvas; Hyewon Chung

2008-01-01

270

An Experimental Two-Way Video Teletraining System: Design, Development and Evaluation.  

ERIC Educational Resources Information Center

Describes the design, development, and evaluation of an experimental two-way video teletraining (VTT) system by the Navy that consisted of two classrooms linked by a land line to enable two-way audio/video communication. Trends in communication and computer technology for training are described, and a cost analysis is included. (12 references)…

Simpson, Henry; And Others

1991-01-01

271

D-OPTIMAL EXPERIMENTAL DESIGNS TO TEST FOR DEPARTURE FROM ADDITIVITY IN A FIXED-RATIO MIXTURE RAY.  

EPA Science Inventory

Humans are exposed to mixtures of environmental compounds. A regulatory assumption is that the mixtures of chemicals act in an additive manner. However, this assumption requires experimental validation. Traditional experimental designs (full factorial) require a large number of e...

272

Scaffolding a Complex Task of Experimental Design in Chemistry with a Computer Environment  

NASA Astrophysics Data System (ADS)

When solving a scientific problem through experimentation, students may have the responsibility to design the experiment. When students work in a conventional condition, with paper and pencil, the designed procedures stay at a very general level. There is a need for additional scaffolds to help the students perform this complex task. We propose a computer environment (copex-chimie) with embedded scaffolds in order to help students to design an experimental procedure. A pre-structuring of the procedure where the students have to choose the actions of their procedure among pre-defined actions and specify the parameters forces the students to face the complexity of the design. However, this is not sufficient for them to succeed; they look for some feedback to improve their procedure and finally abandon their task. In another condition, the students were provided with individualized feedbacks on the errors detected in their procedures by an artificial tutor. These feedbacks proved to be necessary to accompany the students throughout their experimental design without being discouraged. With this kind of scaffold, students worked longer and succeeded better to the task than all the other students.

Girault, Isabelle; d'Ham, Cédric

2014-08-01

273

Man-machine Integration Design and Analysis System (MIDAS) Task Loading Model (TLM) experimental and software detailed design report  

NASA Technical Reports Server (NTRS)

This is the experimental and software detailed design report for the prototype task loading model (TLM) developed as part of the man-machine integration design and analysis system (MIDAS), as implemented and tested in phase 6 of the Army-NASA Aircrew/Aircraft Integration (A3I) Program. The A3I program is an exploratory development effort to advance the capabilities and use of computational representations of human performance and behavior in the design, synthesis, and analysis of manned systems. The MIDAS TLM computationally models the demands designs impose on operators to aide engineers in the conceptual design of aircraft crewstations. This report describes TLM and the results of a series of experiments which were run this phase to test its capabilities as a predictive task demand modeling tool. Specifically, it includes discussions of: the inputs and outputs of TLM, the theories underlying it, the results of the test experiments, the use of the TLM as both stand alone tool and part of a complete human operator simulation, and a brief introduction to the TLM software design.

Staveland, Lowell

1994-01-01

274

Design and Experimental Results for the S827 Airfoil; Period of Performance: 1998--1999  

SciTech Connect

A 21%-thick, natural-laminar-flow airfoil, the S827, for the 75% blade radial station of 40- to 50-meter, stall-regulated, horizontal-axis wind turbines has been designed and analyzed theoretically and verified experimentally in the NASA Langley Low-Turbulence Pressure Tunnel. The primary objective of restrained maximum lift has not been achieved, although the maximum lift is relatively insensitive to roughness, which meets the design goal. The airfoil exhibits a relatively docile stall, which meets the design goal. The primary objective of low profile drag has been achieved. The constraints on the pitching moment and the airfoil thickness have been satisfied. Comparisons of the theoretical and experimental results generally show good agreement with the exception of maximum lift, which is significantly underpredicted.

Somers, D. M.

2005-01-01

275

Comment: Spurious Correlation and Other Observations on Experimental Design for Engineering Dimensional Analysis  

SciTech Connect

This article discusses the paper "Experimental Design for Engineering Dimensional Analysis" by Albrecht et al. (2013, Technometrics). That paper provides and overview of engineering dimensional analysis (DA) for use in developing DA models. The paper proposes methods for generating model-robust experimental designs to supporting fitting DA models. The specific approach is to develop a design that maximizes the efficiency of a specified empirical model (EM) in the original independent variables, subject to a minimum efficiency for a DA model expressed in terms of dimensionless groups (DGs). This discussion article raises several issues and makes recommendations regarding the proposed approach. Also, the concept of spurious correlation is raised and discussed. Spurious correlation results from the response DG being calculated using several independent variables that are also used to calculate predictor DGs in the DA model.

Piepel, Gregory F.

2013-08-01

276

Fertilizer Response Curves for Commercial Southern Forest Species Defined with an Un-Replicated Experimental Design.  

SciTech Connect

There has been recent interest in use of non-replicated regression experimental designs in forestry, as the need for replication in experimental design is burdensome on limited research budgets. We wanted to determine the interacting effects of soil moisture and nutrient availability on the production of various southeastern forest trees (two clones of Populus deltoides, open pollinated Platanus occidentalis, Liquidambar styraciflua and Pinus taeda). Additionally, we required an understanding of the fertilizer response curve. To accomplish both objectives we developed a composite design that includes a core ANOVA approach to consider treatment interactions, with the addition of non-replicated regression plots receiving a range of fertilizer levels for the primary irrigation treatment.

Coleman, Mark; Aubrey, Doug; Coyle, David, R.; Daniels, Richard, F.

2005-11-01

277

Study and design of cryogenic propellant acquisition systems. Volume 2: Supporting experimental program  

NASA Technical Reports Server (NTRS)

Areas of cryogenic fuel systems were identified where critical experimental information was needed either to define a design criteria or to establish the feasibility of a design concept or a critical aspect of a particular design. Such data requirements fell into three broad categories: (1) basic surface tension screen characteristics; (2) screen acquisition device fabrication problems; and (3) screen surface tension device operational failure modes. To explore these problems and to establish design criteria where possible, extensive laboratory or bench test scale experiments were conducted. In general, these proved to be quite successful and, in many instances, the test results were directly used in the system design analyses and development. In some cases, particularly those relating to operational-type problems, areas requiring future research were identified, especially screen heat transfer and vibrational effects.

Burge, G. W.; Blackmon, J. B.

1973-01-01

278

Highly Efficient Design-of-Experiments Methods for Combining CFD Analysis and Experimental Data  

NASA Technical Reports Server (NTRS)

It is the purpose of this study to examine the impact of "highly efficient" Design-of-Experiments (DOE) methods for combining sets of CFD generated analysis data with smaller sets of Experimental test data in order to accurately predict performance results where experimental test data were not obtained. The study examines the impact of micro-ramp flow control on the shock wave boundary layer (SWBL) interaction where a complete paired set of data exist from both CFD analysis and Experimental measurements By combining the complete set of CFD analysis data composed of fifteen (15) cases with a smaller subset of experimental test data containing four/five (4/5) cases, compound data sets (CFD/EXP) were generated which allows the prediction of the complete set of Experimental results No statistical difference were found to exist between the combined (CFD/EXP) generated data sets and the complete Experimental data set composed of fifteen (15) cases. The same optimal micro-ramp configuration was obtained using the (CFD/EXP) generated data as obtained with the complete set of Experimental data, and the DOE response surfaces generated by the two data sets were also not statistically different.

Anderson, Bernhard H.; Haller, Harold S.

2009-01-01

279

Taking evolutionary circuit design from experimentation to implementation: some useful techniques and a silicon demonstration  

NASA Technical Reports Server (NTRS)

Current techniques in evolutionary synthesis of analogue and digital circuits designed at transistor level have focused on achieving the desired functional response, without paying sufficient attention to issues needed for a practical implementation of the resulting solution. No silicon fabrication of circuits with topologies designed by evolution has been done before, leaving open questions on the feasibility of the evolutionary circuit design approach, as well as on how high-performance, robust, or portable such designs could be when implemented in hardware. It is argued that moving from evolutionary 'design-for experimentation' to 'design-for-implementation' requires, beyond inclusion in the fitness function of measures indicative of circuit evaluation factors such as power consumption and robustness to temperature variations, the addition of certain evaluation techniques that are not common in conventional design. Several such techniques that were found to be useful in evolving designs for implementation are presented; some are general, and some are particular to the problem domain of transistor-level logic design, used here as a target application. The example used here is a multifunction NAND/NOR logic gate circuit, for which evolution obtained a creative circuit topology more compact than what has been achieved by multiplexing a NAND and a NOR gate. The circuit was fabricated in a 0.5 mum CMOS technology and silicon tests showed good correspondence with the simulations.

Stoica, A.; Zebulum, R. S.; Guo, X.; Keymeulen, D.; Ferguson, M. I.; Duong, V.

2004-01-01

280

Aspects of experimental design for plant metabolomics experiments and guidelines for growth of plant material.  

PubMed

Experiments involve the deliberate variation of one or more factors in order to provoke responses, the identification of which then provides the first step towards functional knowledge. Because environmental, biological, and/or technical noise is unavoidable, biological experiments usually need to be designed. Thus, once the major sources of experimental noise have been identified, individual samples can be grouped, randomised, and/or pooled. Like other 'omics approaches, metabolomics is characterised by the numbers of analytes largely exceeding sample number. While this unprecedented singularity in biology dramatically increases false discovery, experimental error can nevertheless be decreased in plant metabolomics experiments. For this, each step from plant cultivation to data acquisition needs to be evaluated in order to identify the major sources of error and then an appropriate design can be produced, as with any other experimental approach. The choice of technology, the time at which tissues are harvested, and the way metabolism is quenched also need to be taken into consideration, as they decide which metabolites can be studied. A further recommendation is to document data and metadata in a machine readable way. The latter should also describe every aspect of the experiment. This should provide valuable hints for future experimental design and ultimately give metabolomic data a second life. To facilitate the identification of critical steps, a list of items to be considered before embarking on time-consuming and costly metabolomic experiments is proposed. PMID:22351168

Gibon, Yves; Rolin, Dominique

2012-01-01

281

Single-Case Experimental Designs: A Systematic Review of Published Research and Current Standards  

PubMed Central

This article systematically reviews the research design and methodological characteristics of single-case experimental design (SCED) research published in peer-reviewed journals between 2000 and 2010. SCEDs provide researchers with a flexible and viable alternative to group designs with large sample sizes. However, methodological challenges have precluded widespread implementation and acceptance of the SCED as a viable complementary methodology to the predominant group design. This article includes a description of the research design, measurement, and analysis domains distinctive to the SCED; a discussion of the results within the framework of contemporary standards and guidelines in the field; and a presentation of updated benchmarks for key characteristics (e.g., baseline sampling, method of analysis), and overall, it provides researchers and reviewers with a resource for conducting and evaluating SCED research. The results of the systematic review of 409 studies suggest that recently published SCED research is largely in accordance with contemporary criteria for experimental quality. Analytic method emerged as an area of discord. Comparison of the findings of this review with historical estimates of the use of statistical analysis indicates an upward trend, but visual analysis remains the most common analytic method and also garners the most support amongst those entities providing SCED standards. Although consensus exists along key dimensions of single-case research design and researchers appear to be practicing within these parameters, there remains a need for further evaluation of assessment and sampling techniques and data analytic methods. PMID:22845874

Smith, Justin D.

2013-01-01

282

D-OPTIMAL EXPERIMENTAL DESIGNS TO TEST FOR DEPARTURE FROM ADDITIVITY IN A FIXED-RATIO MIXTURE RAY.  

EPA Science Inventory

Traditional factorial designs for evaluating interactions among chemicals in a mixture are prohibitive when the number of chemicals is large. However, recent advances in statistically-based experimental design have made it easier to evaluate interactions involving many chemicals...

283

Optimal experimental designs for the estimation of thermal properties of composite materials  

NASA Technical Reports Server (NTRS)

Reliable estimation of thermal properties is extremely important in the utilization of new advanced materials, such as composite materials. The accuracy of these estimates can be increased if the experiments are designed carefully. The objectives of this study are to design optimal experiments to be used in the prediction of these thermal properties and to then utilize these designs in the development of an estimation procedure to determine the effective thermal properties (thermal conductivity and volumetric heat capacity). The experiments were optimized by choosing experimental parameters that maximize the temperature derivatives with respect to all of the unknown thermal properties. This procedure has the effect of minimizing the confidence intervals of the resulting thermal property estimates. Both one-dimensional and two-dimensional experimental designs were optimized. A heat flux boundary condition is required in both analyses for the simultaneous estimation of the thermal properties. For the one-dimensional experiment, the parameters optimized were the heating time of the applied heat flux, the temperature sensor location, and the experimental time. In addition to these parameters, the optimal location of the heat flux was also determined for the two-dimensional experiments. Utilizing the optimal one-dimensional experiment, the effective thermal conductivity perpendicular to the fibers and the effective volumetric heat capacity were then estimated for an IM7-Bismaleimide composite material. The estimation procedure used is based on the minimization of a least squares function which incorporates both calculated and measured temperatures and allows for the parameters to be estimated simultaneously.

Scott, Elaine P.; Moncman, Deborah A.

1994-01-01

284

Experimental and theoretical analysis for improved microscope design of optical projection tomographic microscopy.  

PubMed

We present theoretical and experimental results of axial displacement of objects relative to a fixed condenser focal plane (FP) in optical projection tomographic microscopy (OPTM). OPTM produces three-dimensional, reconstructed images of single cells from two-dimensional projections. The cell rotates in a microcapillary to acquire projections from different perspectives where the objective FP is scanned through the cell while the condenser FP remains fixed at the center of the microcapillary. This work uses a combination of experimental and theoretical methods to improve the OPTM instrument design. PMID:23988968

Coe, Ryan L; Seibel, Eric J

2013-09-01

285

Analytical and experimental investigation of liquid double drop dynamics: Preliminary design for space shuttle experiments  

NASA Technical Reports Server (NTRS)

The preliminary grant assessed the use of laboratory experiments for simulating low g liquid drop experiments in the space shuttle environment. Investigations were begun of appropriate immiscible liquid systems, design of experimental apparatus and analyses. The current grant continued these topics, completed construction and preliminary testing of the experimental apparatus, and performed experiments on single and compound liquid drops. A continuing assessment of laboratory capabilities, and the interests of project personnel and available collaborators, led to, after consultations with NASA personnel, a research emphasis specializing on compound drops consisting of hollow plastic or elastic spheroids filled with liquids.

1981-01-01

286

Design and experimental results for a flapped natural-laminar-flow airfoil for general aviation applications  

NASA Technical Reports Server (NTRS)

A flapped natural laminar flow airfoil for general aviation applications, the NLF(1)-0215F, has been designed and analyzed theoretically and verified experimentally in the Langley Low Turbulence Pressure Tunnel. The basic objective of combining the high maximum lift of the NASA low speed airfoils with the low cruise drag of the NACA 6 series airfoils has been achieved. The safety requirement that the maximum lift coefficient not be significantly affected with transition fixed near the leading edge has also been met. Comparisons of the theoretical and experimental results show generally good agreement.

Somers, D. M.

1981-01-01

287

Application of Taguchi philosophy for parametric optimization of bead geometry and HAZ width in submerged arc welding using a mixture of fresh flux and fused flux  

Microsoft Academic Search

Taguchi philosophy has been applied for obtaining optimal parametric combinations to achieve desired weld bead geometry and\\u000a dimensions related to the heat-affected zone (HAZ), such as HAZ width in the present case, in submerged arc welding. The philosophy\\u000a and methodology proposed by Dr. Genichi Taguchi can be used for continuous improvement in products that are produced by submerged\\u000a arc welding.

Saurav Datta; Asish Bandyopadhyay; Pradip Kumar Pal

2008-01-01

288

Development of a Model for Measuring Scientific Processing Skills Based on Brain-Imaging Technology: Focused on the Experimental Design Process  

ERIC Educational Resources Information Center

The purpose of this study was to develop a model for measuring experimental design ability based on functional magnetic resonance imaging (fMRI) during biological inquiry. More specifically, the researchers developed an experimental design task that measures experimental design ability. Using the developed experimental design task, they measured…

Lee, Il-Sun; Byeon, Jung-Ho; Kim, Young-shin; Kwon, Yong-Ju

2014-01-01

289

Active vibration absorber for the CSI evolutionary model - Design and experimental results. [Controls Structures Interaction  

NASA Technical Reports Server (NTRS)

The development of control of large flexible structures technology must include practical demonstrations to aid in the understanding and characterization of controlled structures in space. To support this effort, a testbed facility has been developed to study practical implementation of new control technologies under realistic conditions. The paper discusses the design of a second order, acceleration feedback controller which acts as an active vibration absorber. This controller provides guaranteed stability margins for collocated sensor/actuator pairs in the absence of sensor/actuator dynamics and computational time delay. Experimental results in the presence of these factors are presented and discussed. The robustness of this design under model uncertainty is demonstrated.

Bruner, Anne M.; Belvin, W. Keith; Horta, Lucas G.; Juang, Jer-Nan

1991-01-01

290

An experimental investigation of two 15 percent-scale wind tunnel fan-blade designs  

NASA Technical Reports Server (NTRS)

An experimental 3-D investigation of two fan-blade designs was conducted. The fan blades tested were 15 percent-scale models of blades to be used in the fan drive of the National Full-Scale Aerodynamic Complex at NASA Ames Research Center. NACA 65- and modified NACA 65-series sections incorporated increased thickness on the upper surface, between the leading edge and the one-half-chord position. Twist and taper were the same for both blade designs. The fan blades with modified 65-series sections were found to have an increased stall margin when they were compared with the unmodified blades.

Signor, David B.

1988-01-01

291

Design and construction of an experimental pervious paved parking area to harvest reusable rainwater.  

PubMed

Pervious pavements are sustainable urban drainage systems already known as rainwater infiltration techniques which reduce runoff formation and diffuse pollution in cities. The present research is focused on the design and construction of an experimental parking area, composed of 45 pervious pavement parking bays. Every pervious pavement was experimentally designed to store rainwater and measure the levels of the stored water and its quality over time. Six different pervious surfaces are combined with four different geotextiles in order to test which materials respond better to the good quality of rainwater storage over time and under the specific weather conditions of the north of Spain. The aim of this research was to obtain a good performance of pervious pavements that offered simultaneously a positive urban service and helped to harvest rainwater with a good quality to be used for non potable demands. PMID:22020491

Gomez-Ullate, E; Novo, A V; Bayon, J R; Hernandez, Jorge R; Castro-Fresno, Daniel

2011-01-01

292

Design and Experimental Results for the S825 Airfoil; Period of Performance: 1998-1999  

SciTech Connect

A 17%-thick, natural-laminar-flow airfoil, the S825, for the 75% blade radial station of 20- to 40-meter, variable-speed and variable-pitch (toward feather), horizontal-axis wind turbines has been designed and analyzed theoretically and verified experimentally in the NASA Langley Low-Turbulence Pressure Tunnel. The two primary objectives of high maximum lift, relatively insensitive to roughness and low-profile drag have been achieved. The airfoil exhibits a rapid, trailing-edge stall, which does not meet the design goal of a docile stall. The constraints on the pitching moment and the airfoil thickness have been satisfied. Comparisons of the theoretical and experimental results generally show good agreement.

Somers, D. M.

2005-01-01

293

Theoretical and Experimental Investigation of Mufflers with Comments on Engine-Exhaust Muffler Design  

NASA Technical Reports Server (NTRS)

Equations are presented for the attenuation characteristics of single-chamber and multiple-chamber mufflers of both the expansion-chamber and resonator types, for tuned side-branch tubes, and for the combination of an expansion chamber with a resonator. Experimental curves of attenuation plotted against frequency are presented for 77 different mufflers with a reflection-free tailpipe termination. The experiments were made at room temperature without flow; the sound source was a loud-speaker. A method is given for including the tailpipe reflections in the calculations. Experimental attenuation curves are presented for four different muffler-tailpipe combinations, and the results are compared with the theory. The application of the theory to the design of engine-exhaust mufflers is discussed, and charts are included for the assistance of the designer.

Davis, Don D , Jr; Stokes, George M; Moore, Dewey; Stevens, George L , Jr

1954-01-01

294

Pliocene Model Intercomparison Project (PlioMIP): Experimental Design and Boundary Conditions (Experiment 2)  

NASA Technical Reports Server (NTRS)

The Palaeoclimate Modelling Intercomparison Project has expanded to include a model intercomparison for the mid-Pliocene warm period (3.29 to 2.97 million yr ago). This project is referred to as PlioMIP (the Pliocene Model Intercomparison Project). Two experiments have been agreed upon and together compose the initial phase of PlioMIP. The first (Experiment 1) is being performed with atmosphere only climate models. The second (Experiment 2) utilizes fully coupled ocean-atmosphere climate models. Following on from the publication of the experimental design and boundary conditions for Experiment 1 in Geoscientific Model Development, this paper provides the necessary description of differences and/or additions to the experimental design for Experiment 2.

Haywood, A. M.; Dowsett, H. J.; Robinson, M. M.; Stoll, D. K.; Dolan, A. M.; Lunt, D. J.; Otto-Bliesner, B.; Chandler, M. A.

2011-01-01

295

Production of Lipase from Candida rugosa Using Cheese Whey through Experimental Design and Surface Response Methodology  

Microsoft Academic Search

The present work investigates the production of lipases from Candida rugosa in a culture medium containing cheese whey and also determines the importance of the components of the used culture medium\\u000a using two experimental design and surface response methodology. When pure cheese whey was used as culture medium, the lipolytic\\u000a activity measured in the broth, after 120 h of fermentation, was

Giovana Tommaso; Bruna Souza de Moraes; Gabriela Cruz Macedo; Guilherme Sousa Silva; Eliana Setsuko Kamimura

296

Teaching neurophysiology, neuropharmacology, and experimental design using animal models of psychiatric and neurological disorders  

NSDL National Science Digital Library

Animal models have been widely used for studying the physiology and pharmacology of psychiatric and neurological diseases. The concepts of face, construct, and predictive validity are used as indicators to estimate the extent to which the animal model mimics the disease. Currently, we used these three concepts to design a theoretical assignment to integrate the teaching of neurophysiology, neuropharmacology, and experimental design. For this purpose, seven case studies were developed in which animal models for several psychiatric and neurological diseases were descibed and in which neuroactive drugs used to treat or study these diseases were introduced. Groups of undergraduate students were assigned to one of these case studies and asked to give a classroom presentation in which 1) the disease and underlying pathophysiology are described, 2) face and construct validity of the animal model are discussed, and 3) a pharmacological experiment with the associated neuroactive drug to assess predictive validity is presented. After evaluation of the presentations, we found that the students had gained considerable insight into disease phenomenology, its underlying neurophysiology, and the mechanism of action of the neuroactive drug. Moreover, the assignment was very useful in the teaching of experimental design, allowing an indepth discussion of experimental control groups and the prediction of outcomes in these groups if the animal model were to display predictive validity. Finally, the highly positive responses in the student evaluation forms indicated that the assignment was of great interest to the students. Hence, the currently developed case studies constitute a very useful tool for teaching neurophysiology, neuropharmacology, and experimental design.

Maarten C Morsink (Leiden University of Applied Science Biology); Danny F Dukers (Leiden University of Applied Science Biology and medical Laboratory Research)

2009-03-01

297

Development of a multidose formulation for a humanized monoclonal antibody using experimental design techniques  

Microsoft Academic Search

The purpose of this study was to identify optimal preservatives for a multidose formulation of a humanized monoclonal antibody\\u000a using experimental design techniques. The effect of antimicrobial parenteral preservatives (benzyl alcohol, chlorobutanol,\\u000a methyl paraben, propylparaben, phenol, and m-cresol) on protein stability was assessed using size-exclusion chromatography,\\u000a differential scanning calorimetry, right-angle light scattering, UV spectroscopy, and potency testing using a cell-based

Supriya Gupta; Elizabet Kaisheva

2003-01-01

298

Design and experimental study on an equipment for heating exhaust from turbocharged diesel engine  

Microsoft Academic Search

An pyrogenation equipment which comprises burner, air-taken,and fuel- supplied system is designed to heat the exhaust gas from diesel engine and regenerate the diesel particulate filter. The innovation point lies in using the compressed air from turbocharger to combust with fuel. The equipment is installed between BJ493ZQ3 engine vent-pipe and DPF, the feasibility is testified and the experimental study is

Zi Xin-yun; Yao Guang-tao; Guo Meng-chao; Li Xin

2010-01-01

299

Experimental evaluation of the Battelle accelerated test design for the solar array at Mead, Nebraska  

NASA Technical Reports Server (NTRS)

A previously developed test design for accelerated aging of photovoltaic modules was experimentally evaluated. The studies included a review of relevant field experience, environmental chamber cycling of full size modules, and electrical and physical evaluation of the effects of accelerated aging during and after the tests. The test results indicated that thermally induced fatigue of the interconnects was the primary mode of module failure as measured by normalized power output. No chemical change in the silicone encapsulant was detectable after 360 test cycles.

Frickland, P. O.; Repar, J.

1982-01-01

300

Optimization of thermostable lipase production from a thermophilic Geobacillus sp. using Box-Behnken experimental design  

Microsoft Academic Search

Thermostable lipase production by Geobacillus thermoleovorans was optimized in shake-flask cultures using Box-Behnken experimental design. An empirical model was developed through response surface methodology to describe the relationship between tested variables (Tween 80, olive oil, temperature and pH) and enzyme activity. Maximum enzyme activity (495 U l-1) was attained with Tween 80 at 5 g l-1; olive oil at 60

Yasser Refaat Abdel-Fattah

2002-01-01

301

Design, fabrication, and experimental characterization of a flap valve IPMC micropump with a flexibly supported diaphragm  

Microsoft Academic Search

This paper presents the design, fabrication and experimental characterization of a flap valve ionic polymer–metal composite (IPMC) micropump, the diaphragm of which is supported by a flexible material. A multilayered IPMC based on a Nafion\\/layered silicate and Nafion\\/silica nanocomposites was fabricated and used as an actuator for the micropump. To make best use of a flexible IPMC diaphragm, we introduced

Thanh Tung Nguyen; Nam Seo Goo; Vinh Khanh Nguyen; Youngtai Yoo

2008-01-01

302

Using central composite experimental design to optimize the degradation of black liquor by Fenton reagent  

Microsoft Academic Search

We investigated the advanced oxidation of the black liquor effluent from the pulp and paper industry using the dark Fenton reaction in a lab-scale experiment based on central composite experimental statistical design. The independent variables considered for the optimization of the oxidative process were temperature, H2O2 and Fe(II) concentrations, for a black liquor with a chemical oxygen demand (COD) of

Francesc Torrades; Samuel Saiz; José Antonio García-Hortal

2011-01-01

303

The influence of the design matrix on treatment effect estimates in the quantitative analyses of single-subject experimental design research.  

PubMed

The quantitative methods for analyzing single-subject experimental data have expanded during the last decade, including the use of regression models to statistically analyze the data, but still a lot of questions remain. One question is how to specify predictors in a regression model to account for the specifics of the design and estimate the effect size of interest. These quantitative effect sizes are used in retrospective analyses and allow synthesis of single-subject experimental study results which is informative for evidence-based decision making, research and theory building, and policy discussions. We discuss different design matrices that can be used for the most common single-subject experimental designs (SSEDs), namely, the multiple-baseline designs, reversal designs, and alternating treatment designs, and provide empirical illustrations. The purpose of this article is to guide single-subject experimental data analysts interested in analyzing and meta-analyzing SSED data. PMID:24902590

Moeyaert, Mariola; Ugille, Maaike; Ferron, John M; Beretvas, S Natasha; Van den Noortgate, Wim

2014-09-01

304

Experimental investigation of damage behavior of RC frame members including non-seismically designed columns  

NASA Astrophysics Data System (ADS)

Reinforced concrete (RC) frame structures are one of the mostly common used structural systems, and their seismic performance is largely determined by the performance of columns and beams. This paper describes horizontal cyclic loading tests of ten column and three beam specimens, some of which were designed according to the current seismic design code and others were designed according to the early non-seismic Chinese design code, aiming at reporting the behavior of the damaged or collapsed RC frame strctures observed during the Wenchuan earthquake. The effects of axial load ratio, shear span ratio, and transverse and longitudinal reinforcement ratio on hysteresis behavior, ductility and damage progress were incorporated in the experimental study. Test results indicate that the non-seismically designed columns show premature shear failure, and yield larger maximum residual crack widths and more concrete spalling than the seismically designed columns. In addition, longitudinal steel reinforcement rebars were severely buckled. The axial load ratio and shear span ratio proved to be the most important factors affecting the ductility, crack opening width and closing ability, while the longitudinal reinforcement ratio had only a minor effect on column ductility, but exhibited more influence on beam ductility. Finally, the transverse reinforcement ratio did not influence the maximum residual crack width and closing ability of the seismically designed columns.

Chen, Linzhi; Lu, Xilin; Jiang, Huanjun; Zheng, Jianbo

2009-06-01

305

Experimental design and analysis for accelerated degradation tests with Li-ion cells.  

SciTech Connect

This document describes a general protocol (involving both experimental and data analytic aspects) that is designed to be a roadmap for rapidly obtaining a useful assessment of the average lifetime (at some specified use conditions) that might be expected from cells of a particular design. The proposed experimental protocol involves a series of accelerated degradation experiments. Through the acquisition of degradation data over time specified by the experimental protocol, an unambiguous assessment of the effects of accelerating factors (e.g., temperature and state of charge) on various measures of the health of a cell (e.g., power fade and capacity fade) will result. In order to assess cell lifetime, it is necessary to develop a model that accurately predicts degradation over a range of the experimental factors. In general, it is difficult to specify an appropriate model form without some preliminary analysis of the data. Nevertheless, assuming that the aging phenomenon relates to a chemical reaction with simple first-order rate kinetics, a data analysis protocol is also provided to construct a useful model that relates performance degradation to the levels of the accelerating factors. This model can then be used to make an accurate assessment of the average cell lifetime. The proposed experimental and data analysis protocols are illustrated with a case study involving the effects of accelerated aging on the power output from Gen-2 cells. For this case study, inadequacies of the simple first-order kinetics model were observed. However, a more complex model allowing for the effects of two concurrent mechanisms provided an accurate representation of the experimental data.

Doughty, Daniel Harvey; Thomas, Edward Victor; Jungst, Rudolph George; Roth, Emanuel Peter

2003-08-01

306

Using an Animal Group Vigilance Practical Session to Give Learners a "Heads-Up" to Problems in Experimental Design  

ERIC Educational Resources Information Center

The design of experimental ecological fieldwork is difficult to teach to classes, particularly when protocols for data collection are normally carefully controlled by the class organiser. Normally, reinforcement of the some problems of experimental design such as the avoidance of pseudoreplication and appropriate sampling techniques does not occur…

Rands, Sean A.

2011-01-01

307

Modelling of the Immersion-Depth Effect in a DryWell Temperature Calibrator Using AN Experimental Design  

Microsoft Academic Search

This paper describes an investigation in the design of an improved model of an immersion-depth contact temperature sensor for dry-well heated block temperature calibrators, using experimental design methods. The obtained experimental results exhibit good agreement with the exponential regression model for measured temperature as a result of an appropriate immersion depth of the temperature sensor probe and optimal temperature of

I. Bajsic; B. Blagojevic

2002-01-01

308

Managing Model Data Introduced Uncertainties in Simulator Predictions for Generation IV Systems via Optimum Experimental Design  

SciTech Connect

An optimization technique has been developed to select optimized experimental design specifications to produce data specifically designed to be assimilated to optimize a given reactor concept. Data from the optimized experiment is assimilated to generate posteriori uncertainties on the reactor concept’s core attributes from which the design responses are computed. The reactor concept is then optimized with the new data to realize cost savings by reducing margin. The optimization problem iterates until an optimal experiment is found to maximize the savings. A new generation of innovative nuclear reactor designs, in particular fast neutron spectrum recycle reactors, are being considered for the application of closing the nuclear fuel cycle in the future. Safe and economical design of these reactors will require uncertainty reduction in basic nuclear data which are input to the reactor design. These data uncertainty propagate to design responses which in turn require the reactor designer to incorporate additional safety margin into the design, which often increases the cost of the reactor. Therefore basic nuclear data needs to be improved and this is accomplished through experimentation. Considering the high cost of nuclear experiments, it is desired to have an optimized experiment which will provide the data needed for uncertainty reduction such that a reactor design concept can meet its target accuracies or to allow savings to be realized by reducing the margin required due to uncertainty propagated from basic nuclear data. However, this optimization is coupled to the reactor design itself because with improved data the reactor concept can be re-optimized itself. It is thus desired to find the experiment that gives the best optimized reactor design. Methods are first established to model both the reactor concept and the experiment and to efficiently propagate the basic nuclear data uncertainty through these models to outputs. The representativity of the experiment to the design concept is quantitatively determined. A technique is then established to assimilate this data and produce posteriori uncertainties on key attributes and responses of the design concept. Several experiment perturbations based on engineering judgment are used to demonstrate these methods and also serve as an initial generation of the optimization problem. Finally, an optimization technique is developed which will simultaneously arrive at an optimized experiment to produce an optimized reactor design. Solution of this problem is made possible by the use of the simulated annealing algorithm for solution of optimization problems. The optimization examined in this work is based on maximizing the reactor cost savings associated with the modified design made possible by using the design margin gained through reduced basic nuclear data uncertainties. Cost values for experiment design specifications and reactor design specifications are established and used to compute a total savings by comparing the posteriori reactor cost to the a priori cost plus the cost of the experiment. The optimized solution arrives at a maximized cost savings.

Paul J. Turinsky; Hany S.Abdel-Khalik; Tracy E. Stover

2011-03-31

309

Experimental design of an optimal phase duration control strategy used in batch biological wastewater treatment.  

PubMed

The paper presents the design of an algorithm used in control of a sequencing batch reactor (SBR) for wastewater treatment. The algorithm is used for the on-line optimization of the batch phases duration which should be applied due to the variable input wastewater. Compared to an operation with fixed times of batch phases, this kind of a control strategy improves the treatment quality and reduces energy consumption. The designed control algorithm is based on following the course of some simple indirect process variables (i.e. redox potential, dissolved oxygen concentration and pH), and automatic recognition of the characteristic patterns in their time profile. The algorithm acts on filtered on-line signals and is based on heuristic rules. The control strategy was developed and tested on a laboratory pilot plant. To facilitate the experimentation, the pilot plant was superimposed by a computer-supported experimental environment that enabled: (i) easy access to all data (on-line signals, laboratory measurements, batch parameters) needed for the design of the algorithm, (ii) the immediate application of the algorithm designed off-line in the Matlab package also in real-time control. When testing on the pilot plant, the control strategy demonstrated good agreement between the proposed completion times and actual terminations of the desired biodegradation processes. PMID:11300625

Pavgelj, N B; Hvala, N; Kocijan, J; Ros, M; Subelj, M; Music, G; Strmcnik, S

2001-01-01

310

Active vibration absorber for CSI evolutionary model: Design and experimental results  

NASA Technical Reports Server (NTRS)

The development of control of large flexible structures technology must include practical demonstration to aid in the understanding and characterization of controlled structures in space. To support this effort, a testbed facility was developed to study practical implementation of new control technologies under realistic conditions. The design is discussed of a second order, acceleration feedback controller which acts as an active vibration absorber. This controller provides guaranteed stability margins for collocated sensor/actuator pairs in the absence of sensor/actuator dynamics and computational time delay. The primary performance objective considered is damping augmentation of the first nine structural modes. Comparison of experimental and predicted closed loop damping is presented, including test and simulation time histories for open and closed loop cases. Although the simulation and test results are not in full agreement, robustness of this design under model uncertainty is demonstrated. The basic advantage of this second order controller design is that the stability of the controller is model independent.

Bruner, Anne M.; Belvin, W. Keith; Horta, Lucas G.; Juang, Jer-Nan

1991-01-01

311

The Langley Research Center CSI phase-0 evolutionary model testbed-design and experimental results  

NASA Technical Reports Server (NTRS)

A testbed for the development of Controls Structures Interaction (CSI) technology is described. The design philosophy, capabilities, and early experimental results are presented to introduce some of the ongoing CSI research at NASA-Langley. The testbed, referred to as the Phase 0 version of the CSI Evolutionary model (CEM), is the first stage of model complexity designed to show the benefits of CSI technology and to identify weaknesses in current capabilities. Early closed loop test results have shown non-model based controllers can provide an order of magnitude increase in damping in the first few flexible vibration modes. Model based controllers for higher performance will need to be robust to model uncertainty as verified by System ID tests. Data are presented that show finite element model predictions of frequency differ from those obtained from tests. Plans are also presented for evolution of the CEM to study integrated controller and structure design as well as multiple payload dynamics.

Belvin, W. K.; Horta, Lucas G.; Elliott, K. B.

1991-01-01

312

Conceptual design of a fast-ion D-alpha diagnostic on experimental advanced superconducting tokamak.  

PubMed

To investigate the fast ion behavior, a fast ion D-alpha (FIDA) diagnostic system has been planned and is presently under development on Experimental Advanced Superconducting Tokamak. The greatest challenges for the design of a FIDA diagnostic are its extremely low intensity levels, which are usually significantly below the continuum radiation level and several orders of magnitude below the bulk-ion thermal charge-exchange feature. Moreover, an overlaying Motional Stark Effect (MSE) feature in exactly the same wavelength range can interfere. The simulation of spectra code is used here to guide the design and evaluate the diagnostic performance. The details for the parameters of design and hardware are presented. PMID:25430314

Huang, J; Heidbrink, W W; Wan, B; von Hellermann, M G; Zhu, Y; Gao, W; Wu, C; Li, Y; Fu, J; Lyu, B; Yu, Y; Shi, Y; Ye, M; Hu, L; Hu, C

2014-11-01

313

Design Considerations and Experimental Verification of a Rail Brake Armature Based on Linear Induction Motor Technology  

NASA Astrophysics Data System (ADS)

This paper describes the design considerations and experimental verification of an LIM rail brake armature. In order to generate power and maximize the braking force density despite the limited area between the armature and the rail and the limited space available for installation, we studied a design method that is suitable for designing an LIM rail brake armature; we considered adoption of a ring winding structure. To examine the validity of the proposed design method, we developed a prototype ring winding armature for the rail brakes and examined its electromagnetic characteristics in a dynamic test system with roller rigs. By repeating various tests, we confirmed that unnecessary magnetic field components, which were expected to be present under high speed running condition or when a ring winding armature was used, were not present. Further, the necessary magnetic field component and braking force attained the desired values. These studies have helped us to develop a basic design method that is suitable for designing the LIM rail brake armatures.

Sakamoto, Yasuaki; Kashiwagi, Takayuki; Hasegawa, Hitoshi; Sasakawa, Takashi; Fujii, Nobuo

314

Use of experimental data in testing methods for design against uncertainty  

NASA Astrophysics Data System (ADS)

Modern methods of design take into consideration the fact that uncertainty is present in everyday life, whether in the form of variable loads (the strongest wind that would affect a building), material properties of an alloy, or future demand for the product or cost of labor. Moreover, the Japanese example showed that it may be more cost-effective to design taking into account the existence of the uncertainty rather than to plan to eliminate or greatly reduce it. The dissertation starts by comparing the theoretical basis of two methods for design against uncertainty, namely probability theory and possibility theory. A two-variable design problem is then used to show the differences. It is concluded that for design problems with two or more cases of failure of very different magnitude (as the stop of a car due to lack of gas or motor failure), probability theory divides existent resources in a more intuitive way than possibility theory. The dissertation continues with the description of simple experiments (building towers of dominoes) and then it presents the methodology to increase the amount of information that can be drawn from a given data set. The methodology is shown on the Bidder-Challenger problem, a simulation of a problem of a company that makes microchips to set a target speed for its next microchip. The simulations use the domino experimental data. It is demonstrated that important insights into methods of probability and possibility based design can be gained from experiments.

Rosca, Raluca Ioana

315

Facility for Advanced Accelerator Experimental Tests at SLAC (FACET) Conceptual Design Report  

SciTech Connect

This Conceptual Design Report (CDR) describes the design of FACET. It will be updated to stay current with the developing design of the facility. This CDR begins as the baseline conceptual design and will evolve into an 'as-built' manual for the completed facility. The Executive Summary, Chapter 1, gives an introduction to the FACET project and describes the salient features of its design. Chapter 2 gives an overview of FACET. It describes the general parameters of the machine and the basic approaches to implementation. The FACET project does not include the implementation of specific scientific experiments either for plasma wake-field acceleration for other applications. Nonetheless, enough work has been done to define potential experiments to assure that the facility can meet the requirements of the experimental community. Chapter 3, Scientific Case, describes the planned plasma wakefield and other experiments. Chapter 4, Technical Description of FACET, describes the parameters and design of all technical systems of FACET. FACET uses the first two thirds of the existing SLAC linac to accelerate the beam to about 20GeV, and compress it with the aid of two chicanes, located in Sector 10 and Sector 20. The Sector 20 area will include a focusing system, the generic experimental area and the beam dump. Chapter 5, Management of Scientific Program, describes the management of the scientific program at FACET. Chapter 6, Environment, Safety and Health and Quality Assurance, describes the existing programs at SLAC and their application to the FACET project. It includes a preliminary analysis of safety hazards and the planned mitigation. Chapter 7, Work Breakdown Structure, describes the structure used for developing the cost estimates, which will also be used to manage the project. The chapter defines the scope of work of each element down to level 3.

Amann, J.; Bane, K.; /SLAC

2009-10-30

316

Multi-objective optimization in WEDM of D3 tool steel using integrated approach of Taguchi method & Grey relational analysis  

NASA Astrophysics Data System (ADS)

In this paper, wire electrical discharge machining of D3 tool steel is studied. Influence of pulse-on time, pulse-off time, peak current and wire speed are investigated for MRR, dimensional deviation, gap current and machining time, during intricate machining of D3 tool steel. Taguchi method is used for single characteristics optimization and to optimize all four process parameters simultaneously, Grey relational analysis (GRA) is employed along with Taguchi method. Through GRA, grey relational grade is used as a performance index to determine the optimal setting of process parameters for multi-objective characteristics. Analysis of variance (ANOVA) shows that the peak current is the most significant parameters affecting on multi-objective characteristics. Confirmatory results, proves the potential of GRA to optimize process parameters successfully for multi-objective characteristics.

Shivade, Anand S.; Shinde, Vasudev D.

2014-09-01

317

Experimental design for the optimization of copper biosorption from aqueous solution by Aspergillus terreus.  

PubMed

An experimental design methodology was applied to study the effects of temperature, pH, biomass dose, and stirring speed on copper removal from aqueous solutions by Aspergillus terreus in a biosorption batch system. To identify the effects of the main factors and their interactions on copper removal efficiency and to optimize the process, a full 2(4) factorial design with central points was performed. Four factors were studied at two levels, including stirring speed (50-150 min(-1)), temperature (30-50°C), pH (4-6) and biosorbent dose (0.01-0.175 g). The main factors observed were pH and biomass dose, along with the interactions between pH and biomass, and stirring speed. The optimal operational conditions were obtained using a response surface methodology. The adequacy of the proposed model at 99% confidence level was confirmed by its high adjusted linear coefficient of determination (R(Adj)(2)=0.9452). The best conditions for copper biosorption in the present study were: pH 6, biosorbent dose of 0.175 g, stirring speed of 50 min(-1) and temperature of 50°C. Under these conditions, the maximum predicted copper removal efficiency was 68.52% (adsorption capacity of 15.24 mg/g). The difference between the experimental and predicted copper removal efficiency at the optimal conditions was 4.8%, which implies that the model represented very well the experimental data. PMID:21292385

Cerino-Córdova, F J; García-León, A M; Soto-Regalado, E; Sánchez-González, M N; Lozano-Ramírez, T; García-Avalos, B C; Loredo-Medrano, J A

2012-03-01

318

Introducing Third-Year Chemistry Students to the Planning and Design of an Experimental Program  

NASA Astrophysics Data System (ADS)

The design and planning of an experimental program is often an important aspect of the job description of recent graduate employees in chemical industry and time should therefore be devoted to this activity in an undergraduate course. This paper describes a pencil and paper activity which involves the design and planning of an experimental programme which may lead to the solution of the problem. These skills are an essential pre-requisite to any experimental activity. We provide the students with a list of problems similar to those that a new graduate could encounter on commencing employment in chemical industry. They are real problems, which the Inorganic Chemistry staff of the School have been previously asked to solve for local industry. A staff member acts as the "client", and the students is the "consultant". The aim is that by a series of interviews between the client and the consultant, the students can refine a vague problem statement into a quantitative statement, and then from this develop a proposal to investigate the problem in order to confirm the cause. This proposal is submitted to the client for assessment. The students are expected to arrange one meeting with the supervisor in each week. This activity is highly commended by the School of Applied Chemistry's Advisory Board, which is primarily comprised of industrial chemists.

Dunn, Jeffrey G.; Phillips, David Norman; van Bronswijk, Wilhelm

1997-10-01

319

The Use of Fuzzy Logic in the Taguchi Method for the Optimisation of the Submerged Arc Welding Process  

Microsoft Academic Search

The use of fuzzy logic in the Taguchi method to optimise the submerged arc welding process with multiple performance characteristics\\u000a is reported in this paper. An orthogonal array, the signal-to-noise ratio, multiresponse performance index, and analysis of\\u000a variance are employed to study the performance characteristics in the submerged arc welding process. The process parameters,\\u000a namely arc current, arc voltage, welding

Y. S. Tarng; W. H. Yang; S. C. Juang

2000-01-01

320

Issues and recent advances in optimal experimental design for site investigation (Invited)  

NASA Astrophysics Data System (ADS)

This presentation provides an overview over issues and recent advances in model-based experimental design for site exploration. The addressed issues and advances are (1) how to provide an adequate envelope to prior uncertainty, (2) how to define the information needs in a task-oriented manner, (3) how to measure the expected impact of a data set that it not yet available but only planned to be collected, and (4) how to perform best the optimization of the data collection plan. Among other shortcomings of the state-of-the-art, it is identified that there is a lack of demonstrator studies where exploration schemes based on expert judgment are compared to exploration schemes obtained by optimal experimental design. Such studies will be necessary do address the often voiced concern that experimental design is an academic exercise with little improvement potential over the well- trained gut feeling of field experts. When addressing this concern, a specific focus has to be given to uncertainty in model structure, parameterizations and parameter values, and to related surprises that data often bring about in field studies, but never in synthetic-data based studies. The background of this concern is that, initially, conceptual uncertainty may be so large that surprises are the rule rather than the exception. In such situations, field experts have a large body of experience in handling the surprises, and expert judgment may be good enough compared to meticulous optimization based on a model that is about to be falsified by the incoming data. In order to meet surprises accordingly and adapt to them, there needs to be a sufficient representation of conceptual uncertainty within the models used. Also, it is useless to optimize an entire design under this initial range of uncertainty. Thus, the goal setting of the optimization should include the objective to reduce conceptual uncertainty. A possible way out is to upgrade experimental design theory towards real-time interaction with the ongoing site investigation, such that surprises in the data are immediately accounted for to restrict the conceptual uncertainty and update the optimization of the plan.

Nowak, W.

2013-12-01

321

Experimental characterization and multidisciplinary conceptual design optimization of a bendable load stiffened unmanned air vehicle wing  

NASA Astrophysics Data System (ADS)

Demand for deployable MAVs and UAVs with wings designed to reduce aircraft storage volume led to the development of a bendable wing concept at the University of Florida (UF). The wing shows an ability to load stiffen in the flight load direction, still remaining compliant in the opposite direction, enabling UAV storage inside smaller packing volumes. From the design prospective, when the wing shape parameters are treated as design variables, the performance requirements : high aerodynamic efficiency, structural stability under aggressive flight loads and desired compliant nature to prevent breaking while stored, in general conflict with each other. Creep deformation induced by long term storage and its effect on the wing flight characteristics are additional considerations. Experimental characterization of candidate bendable UAV wings is performed in order to demonstrate and understand aerodynamic and structural behavior of the bendable load stiffened wing under flight loads and while the wings are stored inside a canister for long duration, in the process identifying some important wing shape parameters. A multidisciplinary, multiobjective design optimization approach is utilized for conceptual design of a 24 inch span and 7 inch root chord bendable wing. Aerodynamic performance of the wing is studied using an extended vortex lattice method based Athena Vortex Lattice (AVL) program. An arc length method based nonlinear FEA routine in ABAQUS is used to evaluate the structural performance of the wing and to determine maximum flying velocity that the wing can withstand without buckling or failing under aggressive flight loads. An analytical approach is used to study the stresses developed in the composite wing during storage and Tsai-Wu criterion is used to check failure of the composite wing due to the rolling stresses to determine minimum safe storage diameter. Multidisciplinary wing shape and layup optimization is performed using an elitist non-dominated sorting genetic algorithm: NSGA-II. Simultaneous maximization of aerodynamic efficiency and aggressive flight load carrying capacity are chosen as two design objectives. The design points on the Pareto optimal front thus achieved are compared with a baseline design to observe some designs with improved performance both aerodynamically and structurally. Reliability based optimization concludes the work where uncertainties in design variables, design parameters and modeling are considered to achieve designs satisfying specified reliability constraint.

Jagdale, Vijay Narayan

322

Experimental research of the synthetic jet generator designs based on actuation of diaphragm with piezoelectric actuator  

NASA Astrophysics Data System (ADS)

Experimental analyses of four own developed synthetic jet generator designs were presented in this paper. The main task of this work was to find the most appropriate design of the synthetic jet generator. Dynamic characteristics of the synthetic jet generator's diaphragm with piezoelectric material were measured using non-contact measuring equipment laser vibrometer Polytec®PSV 400. Temperatures of the piezoelectric diaphragms working in resonance frequency were measured with Fiber Bragg Grating (FBG) sensor. Experimental analysis of the synthetic jet generator amplitude-frequency characteristics were performed using CTA (hot wire anemometer) measuring techniques. Piezoelectric diaphragm in diameter of 27 mm was excited by sinusoidal voltage signal and it was fixed tightly inside the chamber of the synthetic jet generator. The number of the synthetic jet generator orifices (1 or 3) and volume of cavity (height of cavity vary from 0.5 mm to 1.5 mm) were changed. The highest value of the synthetic jet velocity 25 m/s was obtained with synthetic jet generator which has cavity 0.5 mm and 1 orifice (resonance frequency of the piezoelectric diaphragm 2.8 kHz). It can be concluded that this type of the design is preferred in order to get the peak velocity of the synthetic jet.

Rimasauskiene, R.; Matejka, M.; Ostachowicz, W.; Kurowski, M.; Malinowski, P.; Wandowski, T.; Rimasauskas, M.

2015-01-01

323

The balloon experimental twin telescope for infrared interferometry (BETTII): optical design  

NASA Astrophysics Data System (ADS)

Here we present the optical and limited cryogenic design for The Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII), an 8-meter far-infrared interferometer designed to fly on a high-altitude scientific balloon. The optical design is separated into warm and cold optics with the cold optics further separated into the far-infrared (FIR) (30-90 microns) and near-infrared (NIR) (1-3 microns). The warm optics are comprised of the twin siderostats, twin telescopes, K-mirror, and warm delay line. The cold optics are comprised of the cold delay line and the transfer optics to the FIR science detector array and the NIR steering array. The field of view of the interferometer is 2', with a wavelength range of 30-90 microns, 0.5" spectral resolution at 40 microns, R~200 spectral resolution, and 1.5" pointing stability. We also present the design of the cryogenic system necessary for operation of the NIR and FIR detectors. The cryogenic system consists of a `Buffered He-7' type cryogenic cooler providing a cold stage base temperature of < 280mK and 10 micro-Watts of heat lift and a custom in-house designed dewar that nominally provides sufficient hold time for the duration of the BETTII flight (24 hours).

Veach, Todd J.; Rinehart, Stephen A.; Mentzell, John E.; Silverberg, Robert F.; Fixsen, Dale J.; Rizzo, Maxime J.; Dhabal, Arnab; Gibbons, Caitlin E.; Benford, Dominic J.

2014-07-01

324

Optimal Experimental Design for Parameter Estimation of a Cell Signaling Model  

PubMed Central

Differential equation models that describe the dynamic changes of biochemical signaling states are important tools to understand cellular behavior. An essential task in building such representations is to infer the affinities, rate constants, and other parameters of a model from actual measurement data. However, intuitive measurement protocols often fail to generate data that restrict the range of possible parameter values. Here we utilized a numerical method to iteratively design optimal live-cell fluorescence microscopy experiments in order to reveal pharmacological and kinetic parameters of a phosphatidylinositol 3,4,5-trisphosphate (PIP3) second messenger signaling process that is deregulated in many tumors. The experimental approach included the activation of endogenous phosphoinositide 3-kinase (PI3K) by chemically induced recruitment of a regulatory peptide, reversible inhibition of PI3K using a kinase inhibitor, and monitoring of the PI3K-mediated production of PIP3 lipids using the pleckstrin homology (PH) domain of Akt. We found that an intuitively planned and established experimental protocol did not yield data from which relevant parameters could be inferred. Starting from a set of poorly defined model parameters derived from the intuitively planned experiment, we calculated concentration-time profiles for both the inducing and the inhibitory compound that would minimize the predicted uncertainty of parameter estimates. Two cycles of optimization and experimentation were sufficient to narrowly confine the model parameters, with the mean variance of estimates dropping more than sixty-fold. Thus, optimal experimental design proved to be a powerful strategy to minimize the number of experiments needed to infer biological parameters from a cell signaling assay. PMID:19911077

Bandara, Samuel; Schlöder, Johannes P.; Eils, Roland; Bock, Hans Georg; Meyer, Tobias

2009-01-01

325

Experimental design in caecilian systematics: phylogenetic information of mitochondrial genomes and nuclear rag1.  

PubMed

In molecular phylogenetic studies, a major aspect of experimental design concerns the choice of markers and taxa. Although previous studies have investigated the phylogenetic performance of different genes and the effectiveness of increasing taxon sampling, their conclusions are partly contradictory, probably because they are highly context specific and dependent on the group of organisms used in each study. Goldman introduced a method for experimental design in phylogenetics based on the expected information to be gained that has barely been used in practice. Here we use this method to explore the phylogenetic utility of mitochondrial (mt) genes, mt genomes, and nuclear rag1 for studies of the systematics of caecilian amphibians, as well as the effect of taxon addition on the stabilization of a controversial branch of the tree. Overall phylogenetic information estimates per gene, specific estimates per branch of the tree, estimates for combined (mitogenomic) data sets, and estimates as a hypothetical new taxon is added to different parts of the caecilian tree are calculated and compared. In general, the most informative data sets are those for mt transfer and ribosomal RNA genes. Our results also show at which positions in the caecilian tree the addition of taxa have the greatest potential to increase phylogenetic information with respect to the controversial relationships of Scolecomorphus, Boulengerula, and all other teresomatan caecilians. These positions are, as intuitively expected, mostly (but not all) adjacent to the controversial branch. Generating whole mitogenomic and rag1 data for additional taxa joining the Scolecomorphus branch may be a more efficient strategy than sequencing a similar amount of additional nucleotides spread across the current caecilian taxon sampling. The methodology employed in this study allows an a priori evaluation and testable predictions of the appropriateness of particular experimental designs to solve specific questions at different levels of the caecilian phylogeny. PMID:20525595

San Mauro, Diego; Gower, David J; Massingham, Tim; Wilkinson, Mark; Zardoya, Rafael; Cotton, James A

2009-08-01

326

Didanosine extended-release matrix tablets: optimization of formulation variables using statistical experimental design.  

PubMed

Statistical experimental design was applied to evaluate the influence of some process and formulation variables and possible interactions among such variables, on didanosine release from directly-compressed matrix tablets based on blends of two insoluble polymers, Eudragit RS-PM and Ethocel 100, with the final goal of drug release behavior optimization. The considered responses were the percent of drug released at three determined times, the dissolution efficiency at 6 h and the time to dissolve 10% of drug. Four independent variables were considered: tablet compression force, ratio between the polymers and their particle size, and drug content. The preliminary screening step, carried out by means of a 12-run asymmetric screening matrix according to a D-optimal design strategy, allowed evaluation of the effects of different levels of each variable. The drug content and the polymers ratio had the most important effect on drug release, which, moreover, was favored by greater polymers particle size; on the contrary the compression force did not have a significant effect. The Doehlert design was then applied for a response-surface study, in order to study in depth the effects of the most important variables. The desirability function was used to simultaneously optimize the five considered responses, each having a different target. This procedure allowed selection, in the studied experimental domain, of the best formulation conditions to optimize drug release rate. The experimental values obtained from the optimized formulation highly agreed with the predicted values. The results demonstrated the reliability of the model in the preparation of extended-release matrix tablets with predictable drug release profiles. PMID:11955809

Sánchez-Lafuente, Carla; Furlanetto, Sandra; Fernández-Arévalo, Mercedes; Alvarez-Fuentes, Josefa; Rabasco, Antonio M; Faucci, M Teresa; Pinzauti, Sergio; Mura, Paola

2002-04-26

327

Aerodynamic Design of Axial-flow Compressors. VI - Experimental Flow in Two-Dimensional Cascades  

NASA Technical Reports Server (NTRS)

Available experimental two-dimensional cascade data for conventional compressor blade sections are correlated at a reference incidence angle in the region of minimum loss. Variations of reference incidence angle, total-pressure loss, and deviation angle with cascade geometry, inlet Mach number, and Reynolds number are investigated. From the analysis and the correlations of the available data, rules and relations are evolved for the prediction of blade-profile performance. These relations are developed in simplified forms readily applicable to compressor design procedures.

Lieblein, Seymour

1955-01-01

328

Conceptual design of experimental equipment for large-diameter NTD-Si.  

PubMed

An irradiation-experimental equipment for 12in neutron transmutation doping silicon (NTD-Si) was designed conceptually by using MCNP5 in order to improve the neutron flux distribution of the radial direction. As a result of the calculations, the neutron absorption reaction ratio of the circumference to the center could be limited within 1.09 using a thermal neutron filter that covers the surface of the silicon ingot. The uniformity of the (30)Si neutron absorption was less than 5.3%. PMID:19299158

Yagi, M; Watanabe, M; Ohyama, K; Yamamoto, K; Komeda, M; Kashima, Y; Yamashita, K

2009-01-01

329

Quiet Clean Short-Haul Experimental Engine (QCSEE): Acoustic treatment development and design  

NASA Technical Reports Server (NTRS)

Acoustic treatment designs for the quiet clean short-haul experimental engines are defined. The procedures used in the development of each noise-source suppressor device are presented and discussed in detail. A complete description of all treatment concepts considered and the test facilities utilized in obtaining background data used in treatment development are also described. Additional supporting investigations that are complementary to the treatment development work are presented. The expected suppression results for each treatment configuration are given in terms of delta SPL versus frequency and in terms of delta PNdB.

Clemons, A.

1979-01-01

330

Design and experimental investigations on a small scale traveling wave thermoacoustic engine  

NASA Astrophysics Data System (ADS)

A small scale traveling wave or Stirling thermoacoustic engine with a resonator of only 1 m length was designed, constructed and tested by using nitrogen as working gas. The small heat engine achieved a steady working frequency of 45 Hz. The pressure ratio reached 1.189, with an average charge pressure of 0.53 MPa and a heating power of 1.14 kW. The temperature and the pressure characteristics during the onset and damping processes were also observed and discussed. The experimental results demonstrated that the small engine possessed the potential to drive a Stirling-type pulse tube cryocooler.

Chen, M.; Ju, Y. L.

2013-02-01

331

Final Design and Experimental Validation of the Thermal Performance of the LHC Lattice Cryostats  

E-print Network

The recent commissioning and operation of the LHC String 2 have given a first experimental validation of the global thermal performance of the LHC lattice cryostat at nominal cryogenic conditions. The cryostat designed to minimize the heat inleak from ambient temperature, houses under vacuum and thermally protects the cold mass, which contains the LHC twin-aperture superconducting magnets operating at 1.9 K in superfluid helium. Mechanical components linking the cold mass to the vacuum vessel, such as support posts and insulation vacuum barriers are designed with efficient thermalisations for heat interception to minimise heat conduction. Heat inleak by radiation is reduced by employing multilayer insulation (MLI) wrapped around the cold mass and around an aluminium thermal shield cooled to about 60 K. Measurements of the total helium vaporization rate in String 2 gives, after substraction of supplementary heat loads and end effects, an estimate of the total thermal load to a standard LHC cell (107 m) includi...

Bourcey, N; Parma, V; Poncet, A; Rohmig, P; Serio, L; Skoczen, Blazej; Tock, J P; Williams, L R

2004-01-01

332

Design and Experimental Performance of a Two Stage Partial Admission Turbine, Task B.1/B.4  

NASA Technical Reports Server (NTRS)

A three-inch mean diameter, two-stage turbine with partial admission in each stage was experimentally investigated over a range of admissions and angular orientations of admission arcs. Three configurations were tested in which first stage admission varied from 37.4 percent (10 of 29 passages open, 5 per side) to 6.9 percent (2 open, 1 per side). Corresponding second stage admissions were 45.2 percent (14 of 31 passages open, 7 per side) and 12.9 percent (4 open, 2 per side). Angular positions of the second stage admission arcs with respect to the first stage varied over a range of 70 degrees. Design and off-design efficiency and flow characteristics for the three configurations are presented. The results indicated that peak efficiency and the corresponding isentropic velocity ratio decreased as the arcs of admission were decreased. Both efficiency and flow characteristics were sensitive to the second stage nozzle orientation angles.

Sutton, R. F.; Boynton, J. L.; Akian, R. A.; Shea, Dan; Roschak, Edmund; Rojas, Lou; Orr, Linsey; Davis, Linda; King, Brad; Bubel, Bill

1992-01-01

333

Conceptual design study of Fusion Experimental Reactor (FY86 FER): Safety  

NASA Astrophysics Data System (ADS)

This report describes the study on safety for FER (Fusion Experimental Reactor) which has been designed as a next step machine to the JT-60. Though the final purpose of this study is to have an image of design base accident, maximum credible accident and to assess their risk or probability, etc., as FER plant system, the emphasis of this years study is placed on fuel-gas circulation system where the tritium inventory is maximum. The report consists of two chapters. The first chapter summarizes the FER system and describes FMEA (Failure Mode and Effect Analysis) and related accident progression sequence for FER plant system as a whole. The second chapter of this report is focused on fuel-gas circulation system including purification, isotope separation and storage. Probability of risk is assessed by the probabilistic risk analysis (PRA) procedure based on FMEA, ETA and FTA.

Seki, Yasushi; Iida, Hiromasa; Honda, Tsutomu

1987-08-01

334

Experimental evaluation of an advanced Space Shuttle Main Engine hot-gas manifold design concept  

NASA Technical Reports Server (NTRS)

The Space Shuttle Main Engine's hot gas manifold (HGM) has been the subject of an experimental study aimed at the establishment of an aerodynamic data base to support the development of an advanced, three-dimensional, fluid dynamic analysis computer model. The advanced HGM design used in the study demonstrated improved flow uniformity in the fuel-side turbine exit and transfer duct exit regions. Major modifications were incorporated in the HGM flow test article model, using two large transfer ducts on the fuel turbine side in place of the three small transfer ducts of the present design. The HGM flow field data were found to be essentially independent of Reynolds number over the range examined.

Pelaccio, D. G.; Lepore, F. F.; Oconnor, G. M.; Rao, G. V. R.; Ratekin, G. H.; Vogt, S. T.

1984-01-01

335

Inlet Flow Test Calibration for a Small Axial Compressor Facility. Part 1: Design and Experimental Results  

NASA Technical Reports Server (NTRS)

An axial compressor test rig has been designed for the operation of small turbomachines. The inlet region consisted of a long flowpath region with two series of support struts and a flapped inlet guide vane. A flow test was run to calibrate and determine the source and magnitudes of the loss mechanisms in the inlet for a highly loaded two-stage axial compressor test. Several flow conditions and IGV angle settings were established in which detailed surveys were completed. Boundary layer bleed was also provided along the casing of the inlet behind the support struts and ahead of the IGV. A detailed discussion of the flowpath design along with a summary of the experimental results are provided in Part 1.

Miller, D. P.; Prahst, P. S.

1994-01-01

336

Experimental validation of an integrated controls-structures design methodology for a class of flexible space structures  

NASA Technical Reports Server (NTRS)

This paper describes the first experimental validation of an optimization-based integrated controls-structures design methodology for a class of flexible space structures. The Controls-Structures-Interaction (CSI) Evolutionary Model, a laboratory test bed at Langley, is redesigned based on the integrated design methodology with two different dissipative control strategies. The redesigned structure is fabricated, assembled in the laboratory, and experimentally compared with the original test structure. Design guides are proposed and used in the integrated design process to ensure that the resulting structure can be fabricated. Experimental results indicate that the integrated design requires greater than 60 percent less average control power (by thruster actuators) than the conventional control-optimized design while maintaining the required line-of-sight performance, thereby confirming the analytical findings about the superiority of the integrated design methodology. Amenability of the integrated design structure to other control strategies is considered and evaluated analytically and experimentally. This work also demonstrates the capabilities of the Langley-developed design tool CSI DESIGN which provides a unified environment for structural and control design.

Maghami, Peiman G.; Gupta, Sandeep; Elliott, Kenny B.; Joshi, Suresh M.; Walz, Joseph E.

1994-01-01

337

Design and Development of a Composite Dome for Experimental Characterization of Material Permeability  

NASA Technical Reports Server (NTRS)

This paper presents the design and development of a carbon fiber reinforced plastic dome, including a description of the dome fabrication, method for sealing penetrations in the dome, and a summary of the planned test series. This dome will be used for the experimental permeability characterization and leakage validation of composite vessels pressurized using liquid hydrogen and liquid nitrogen at the Cryostat Test Facility at the NASA Marshall Space Flight Center (MSFC). The preliminary design of the dome was completed using membrane shell analysis. Due to the configuration of the test setup, the dome will experience some flexural stresses and stress concentrations in addition to membrane stresses. Also, a potential buckling condition exists for the dome due to external pressure during the leak testing of the cryostat facility lines. Thus, a finite element analysis was conducted to assess the overall strength and stability of the dome for each required test condition. Based on these results, additional plies of composite reinforcement material were applied to local regions on the dome to alleviate stress concentrations and limit deflections. The dome design includes a circular opening in the center for the installation of a polar boss, which introduces a geometric discontinuity that causes high stresses in the region near the hole. To attenuate these high stresses, a reinforcement system was designed using analytical and finite element analyses. The development of a low leakage polar boss system is also investigated.

Estrada, Hector; Smeltzer, Stanley S., III

1999-01-01

338

Design and Computational/Experimental Analysis of Low Sonic Boom Configurations  

NASA Technical Reports Server (NTRS)

Recent studies have shown that inviscid CFD codes combined with a planar extrapolation method give accurate sonic boom pressure signatures at distances greater than one body length from supersonic configurations if either adapted grids swept at the approximate Mach angle or very dense non-adapted grids are used. The validation of CFD for computing sonic boom pressure signatures provided the confidence needed to undertake the design of new supersonic transport configurations with low sonic boom characteristics. An aircraft synthesis code in combination with CFD and an extrapolation method were used to close the design. The principal configuration of this study is designated LBWT (Low Boom Wing Tail) and has a highly swept cranked arrow wing with conventional tails, and was designed to accommodate either 3 or 4 engines. The complete configuration including nacelles and boundary layer diverters was evaluated using the AIRPLANE code. This computer program solves the Euler equations on an unstructured tetrahedral mesh. Computations and wind tunnel data for the LBWT and two other low boom configurations designed at NASA Ames Research Center are presented. The two additional configurations are included to provide a basis for comparing the performance and sonic boom level of the LBWT with contemporary low boom designs and to give a broader experiment/CFD correlation study. The computational pressure signatures for the three configurations are contrasted with on-ground-track near-field experimental data from the NASA Ames 9x7 Foot Supersonic Wind Tunnel. Computed pressure signatures for the LBWT are also compared with experiment at approximately 15 degrees off ground track.

Cliff, Susan E.; Baker, Timothy J.; Hicks, Raymond M.

1999-01-01

339

Sonophotolytic degradation of synthetic pharmaceutical wastewater: Statistical experimental design and modeling.  

PubMed

The merits of the sonophotolysis as a combination of sonolysis (US) and photolysis (UV/H2O2) are investigated in a pilot-scale external loop airlift sonophotoreactor for the treatment of a synthetic pharmaceutical wastewater (SPWW). In the first part of this study, the multivariate experimental design is carried out using Box-Behnken design (BBD). The effluent is characterized by the total organic carbon (TOC) percent removal as a surrogate parameter. The results indicate that the response of the TOC percent removal is significantly affected by the synergistic effects of the linear term of H2O2 dosage and ultrasound power with the antagonistic effect of quadratic term of H2O2 dosage. The statistical analysis of the results indicates a satisfactory prediction of the system behavior by the developed model. In the second part of this study, a novel rigorous mathematical model for the sonophotolytic process is developed to predict the TOC percent removal as a function of time. The mathematical model is based on extensively accepted sonophotochemical reactions and the rate constants in advanced oxidation processes. A good agreement between the model predictions and experimental data indicates that the proposed model could successfully describe the sonophotolysis of the pharmaceutical wastewater. PMID:25460426

Ghafoori, Samira; Mowla, Amir; Jahani, Ramtin; Mehrvar, Mehrab; Chan, Philip K

2015-03-01

340

Model Development and Experimental Validation of the Fusible Heat Sink Design for Exploration Vehicles  

NASA Technical Reports Server (NTRS)

The Fusible Heat Sink is a novel vehicle heat rejection technology which combines a flow through radiator with a phase change material. The combined technologies create a multi-function device able to shield crew members against Solar Particle Events (SPE), reduce radiator extent by permitting sizing to the average vehicle heat load rather than to the peak vehicle heat load, and to substantially absorb heat load excursions from the average while constantly maintaining thermal control system setpoints. This multi-function technology provides great flexibility for mission planning, making it possible to operate a vehicle in hot or cold environments and under high or low heat load conditions for extended periods of time. This paper describes the model development and experimental validation of the Fusible Heat Sink technology. The model developed was intended to meet the radiation and heat rejection requirements of a nominal MMSEV mission. Development parameters and results, including sizing and model performance will be discussed. From this flight-sized model, a scaled test-article design was modeled, designed, and fabricated for experimental validation of the technology at Johnson Space Center thermal vacuum chamber facilities. Testing showed performance comparable to the model at nominal loads and the capability to maintain heat loads substantially greater than nominal for extended periods of time.

Cognata, Thomas J.; Leimkuehler, Thomas O.; Sheth, Rubik B.; Le,Hung

2012-01-01

341

Model Development and Experimental Validation of the Fusible Heat Sink Design for Exploration Vehicles  

NASA Technical Reports Server (NTRS)

The Fusible Heat Sink is a novel vehicle heat rejection technology which combines a flow through radiator with a phase change material. The combined technologies create a multi-function device able to shield crew members against Solar Particle Events (SPE), reduce radiator extent by permitting sizing to the average vehicle heat load rather than to the peak vehicle heat load, and to substantially absorb heat load excursions from the average while constantly maintaining thermal control system setpoints. This multi-function technology provides great flexibility for mission planning, making it possible to operate a vehicle in hot or cold environments and under high or low heat load conditions for extended periods of time. This paper describes the modeling and experimental validation of the Fusible Heat Sink technology. The model developed was intended to meet the radiation and heat rejection requirements of a nominal MMSEV mission. Development parameters and results, including sizing and model performance will be discussed. From this flight-sized model, a scaled test-article design was modeled, designed, and fabricated for experimental validation of the technology at Johnson Space Center thermal vacuum chamber facilities. Testing showed performance comparable to the model at nominal loads and the capability to maintain heat loads substantially greater than nominal for extended periods of time.

Cognata, Thomas J.; Leimkuehler, Thomas; Sheth, Rubik; Le, Hung

2013-01-01

342

Supersonic Retro-Propulsion Experimental Design for Computational Fluid Dynamics Model Validation  

NASA Technical Reports Server (NTRS)

The development of supersonic retro-propulsion, an enabling technology for heavy payload exploration missions to Mars, is the primary focus for the present paper. A new experimental model, intended to provide computational fluid dynamics model validation data, was recently designed for the Langley Research Center Unitary Plan Wind Tunnel Test Section 2. Pre-test computations were instrumental for sizing and refining the model, over the Mach number range of 2.4 to 4.6, such that tunnel blockage and internal flow separation issues would be minimized. A 5-in diameter 70-deg sphere-cone forebody, which accommodates up to four 4:1 area ratio nozzles, followed by a 10-in long cylindrical aftbody was developed for this study based on the computational results. The model was designed to allow for a large number of surface pressure measurements on the forebody and aftbody. Supplemental data included high-speed Schlieren video and internal pressures and temperatures. The run matrix was developed to allow for the quantification of various sources of experimental uncertainty, such as random errors due to run-to-run variations and bias errors due to flow field or model misalignments. Some preliminary results and observations from the test are presented, although detailed analyses of the data and uncertainties are still on going.

Berry, Scott A.; Laws, Christopher T.; Kleb, W. L.; Rhode, Matthew N.; Spells, Courtney; McCrea, Andrew C.; Truble, Kerry A.; Schauerhamer, Daniel G.; Oberkampf, William L.

2011-01-01

343

A validated spectrofluorimetric method for the determination of nifuroxazide through coumarin formation using experimental design  

PubMed Central

Background Nifuroxazide (NF) is an oral nitrofuran antibiotic, having a wide range of bactericidal activity against gram positive and gram negative enteropathogenic organisms. It is formulated either in single form, as intestinal antiseptic or in combination with drotaverine (DV) for the treatment of gastroenteritis accompanied with gastrointestinal spasm. Spectrofluorimetry is a convenient and sensitive technique for pharmaceutical quality control. The new proposed spectrofluorimetric method allows its determination either in single form or in binary mixture with DV. Furthermore, experimental conditions were optimized using the new approach: Experimental design, which has many advantages over the old one, one variable at a time (OVAT approach). Results A novel and sensitive spectrofluorimetric method was designed and validated for the determination of NF in pharmaceutical formulation. The method was based upon the formation of a highly fluorescent coumarin compound by the reaction between NF and ethylacetoacetate (EAA) using sulfuric acid as catalyst. The fluorescence was measured at 390 nm upon excitation at 340 nm. Experimental design was used to optimize experimental conditions. Volumes of EAA and sulfuric acid, temperature and heating time were considered the critical factors to be studied in order to establish an optimum fluorescence. Each two factors were co-tried at three levels. Regression analysis revealed good correlation between fluorescence intensity and concentration over the range 20–400 ng ml-1. The suggested method was successfully applied for the determination of NF in pure and capsule forms. The procedure was validated in terms of linearity, accuracy, precision, limit of detection and limit of quantification. The selectivity of the method was investigated by analysis of NF in presence of the co-mixed drug DV where no interference was observed. The reaction pathway was suggested and the structure of the fluorescent product was proposed. Statistical comparison between the presented method and a reported spectrophotometric one was carried out on pure and pharmaceutical formulation and revealed no significant difference. Conclusion The proposed method was considered economic, accurate, precise and highly sensitive. It could be easily applied in laboratory quality control for the analysis of NF in pure form and in pharmaceutical dosage form. PMID:23702256

2013-01-01

344

Network Pharmacology Strategies Toward Multi-Target Anticancer Therapies: From Computational Models to Experimental Design Principles  

PubMed Central

Polypharmacology has emerged as novel means in drug discovery for improving treatment response in clinical use. However, to really capitalize on the polypharmacological effects of drugs, there is a critical need to better model and understand how the complex interactions between drugs and their cellular targets contribute to drug efficacy and possible side effects. Network graphs provide a convenient modeling framework for dealing with the fact that most drugs act on cellular systems through targeting multiple proteins both through on-target and off-target binding. Network pharmacology models aim at addressing questions such as how and where in the disease network should one target to inhibit disease phenotypes, such as cancer growth, ideally leading to therapies that are less vulnerable to drug resistance and side effects by means of attacking the disease network at the systems level through synergistic and synthetic lethal interactions. Since the exponentially increasing number of potential drug target combinations makes pure experimental approach quickly unfeasible, this review depicts a number of computational models and algorithms that can effectively reduce the search space for determining the most promising combinations for experimental evaluation. Such computational-experimental strategies are geared toward realizing the full potential of multi-target treatments in different disease phenotypes. Our specific focus is on system-level network approaches to polypharmacology designs in anticancer drug discovery, where we give representative examples of how network-centric modeling may offer systematic strategies toward better understanding and even predicting the phenotypic responses to multi-target therapies.

Tang, Jing; Aittokallio, Tero

2014-01-01

345

Design of an experimental loop for post-LOCA heat transfer regimes in a Gas-cooled Fast Reactor  

E-print Network

The goal of this thesis is to design an experimental thermal-hydraulic loop capable of generating accurate, reliable data in various convection heat transfer regimes for use in the formulation of a comprehensive convection ...

Cochran, Peter A. (Peter Andrew)

2005-01-01

346

Passing of northern pike and common carp through experimental barriers designed for use in wetland restoration  

USGS Publications Warehouse

Restoration plans for Metzger Marsh, a coastal wetland on the south shore of western Lake Erie, incorporated a fish-control system designed to restrict access to the wetland by large common carp (Cyprinus carpio). Ingress fish passageways in the structure contain slots into which experimental grates of varying size and shape can be placed to selectively allow entry and transfer of other large fish species while minimizing the number of common carp to be handled. We tested different sizes and shapes of grates in experimental tanks in the laboratory to determine the best design for testing in the field. We also tested northern pike (Esox lucius) because lack of access to wetland spawning habitat has greatly reduced their populations in western Lake Erie. Based on our results, vertical bar grates were chosen for installation because common carp were able to pass through circular grates smaller than body height by compressing their soft abdomens; they passed through rectangular grates on the diagonal. Vertical bar grates with 5-cm spacing that were installed across much of the control structure should limit access of common carp larger than 34 cm total length (TL) and northern pike larger than 70 cm. Vertical bar grates selected for initial field trials in the fish passageway had spacings of 5.8 and 6.6 cm, which increased access by common carp to 40 and 47 cm TL and by northern pike to 76 and 81 cm, respectively. The percentage of potential common carp biomass (fish seeking entry) that must be handled in lift baskets in the passageway increased from 0.9 to 4.8 to 15.4 with each increase in spacing between bars. Further increases in spacing would greatly increase the number of common carp that would have to be handled. The results of field testing should be useful in designing selective fish-control systems for other wetland restoration sites adjacent to large water bodies.

French, John R. P., III; Wilcox, Douglas A.; Nichols, S. Jerrine

1999-01-01

347

De Novo Peptide Design and Experimental Validation of Histone Methyltransferase Inhibitors  

PubMed Central

Histones are small proteins critical to the efficient packaging of DNA in the nucleus. DNA–protein complexes, known as nucleosomes, are formed when the DNA winds itself around the surface of the histones. The methylation of histone residues by enhancer of zeste homolog 2 (EZH2) maintains gene repression over successive cell generations. Overexpression of EZH2 can silence important tumor suppressor genes leading to increased invasiveness of many types of cancers. This makes the inhibition of EZH2 an important target in the development of cancer therapeutics. We employed a three-stage computational de novo peptide design method to design inhibitory peptides of EZH2. The method consists of a sequence selection stage and two validation stages for fold specificity and approximate binding affinity. The sequence selection stage consists of an integer linear optimization model that was solved to produce a rank-ordered list of amino acid sequences with increased stability in the bound peptide-EZH2 structure. These sequences were validated through the calculation of the fold specificity and approximate binding affinity of the designed peptides. Here we report the discovery of novel EZH2 inhibitory peptides using the de novo peptide design method. The computationally discovered peptides were experimentally validated in vitro using dose titrations and mechanism of action enzymatic assays. The peptide with the highest in vitro response, SQ037, was validated in nucleo using quantitative mass spectrometry-based proteomics. This peptide had an IC50 of 13.5 M, demonstrated greater potency as an inhibitor when compared to the native and K27A mutant control peptides, and demonstrated competitive inhibition versus the peptide substrate. Additionally, this peptide demonstrated high specificity to the EZH2 target in comparison to other histone methyltransferases. The validated peptides are the first computationally designed peptides that directly inhibit EZH2. These inhibitors should prove useful for further chromatin biology investigations. PMID:24587223

Smadbeck, James; Peterson, Meghan B.; Zee, Barry M.; Garapaty, Shivani; Mago, Aashna; Lee, Christina; Giannis, Athanassios; Trojer, Patrick; Garcia, Benjamin A.; Floudas, Christodoulos A.

2014-01-01

348

Experimental design of pulsed CO2 laser damage threshold testing at the high-energy laser systems test facility  

Microsoft Academic Search

Experimental laser damage threshold tests were designed and successfully carried out at the High Energy Laser Systems Test Facility utilizing the Pulsed Laser Vulnerability Test System against optical components from a tactical weapon system in a simulated battlefield environment. The objectives of the experimental tests were to measure laser fluence levels corresponding to minimum damage, maximum functional degradation, and catastrophic

Chris T. Beairsto; Stephen M. Squires; Kevin J. Suter

1994-01-01

349

Design and experimental validation for direct-drive fault-tolerant permanent-magnet vernier machines.  

PubMed

A fault-tolerant permanent-magnet vernier (FT-PMV) machine is designed for direct-drive applications, incorporating the merits of high torque density and high reliability. Based on the so-called magnetic gearing effect, PMV machines have the ability of high torque density by introducing the flux-modulation poles (FMPs). This paper investigates the fault-tolerant characteristic of PMV machines and provides a design method, which is able to not only meet the fault-tolerant requirements but also keep the ability of high torque density. The operation principle of the proposed machine has been analyzed. The design process and optimization are presented specifically, such as the combination of slots and poles, the winding distribution, and the dimensions of PMs and teeth. By using the time-stepping finite element method (TS-FEM), the machine performances are evaluated. Finally, the FT-PMV machine is manufactured, and the experimental results are presented to validate the theoretical analysis. PMID:25045729

Liu, Guohai; Yang, Junqin; Chen, Ming; Chen, Qian

2014-01-01

350

Design and experimental evidence of a flat graded-index photonic crystal lens  

NASA Astrophysics Data System (ADS)

We report on the design and the experimental evidence of a flat graded index photonic crystal lens. The gradient has been designed so that the flat slab focuses a plane wave and so that it converts the wave issued from a point source into a plane wave. This graded-index photonic crystal lens operates as a convex lens. The gradient of index results from varying the filling factor of the photonic crystal in the direction perpendicular to that of the propagation of the electromagnetic field. The shape of the gradient of index has been designed by engineering the iso-frequency curves of the photonic crystal. As only a few layers were necessary and as graded photonic crystals may be fabricated by a variety of processes, this shows the ability of graded photonic crystals to efficiently apply for various photonic devices, from microwave range to the optical domain. 42.70.Qs Photonic bandgap materials, 78.67.Pt Optical properties of photonic structures, 41.20.Jb Electromagnetic wave propagation; radiowave propagation 84.40.Ba Antennas.

Gaufillet, F.; Akmansoy, É.

2013-08-01

351

Rugby-like hohlraum experimental designs for demonstrating x-ray drive enhancement  

NASA Astrophysics Data System (ADS)

A suite of experimental designs for the Omega laser facility [Boehly et al., Opt. Commun. 133, 495 (1997)] using rugby and cylindrical hohlraums is proposed to confirm the energetics benefits of rugby-shaped hohlraums over cylinders under optimal implosion symmetry conditions. Postprocessed Dante x-ray drive measurements predict a 12-17eV (23%-36%) peak hohlraum temperature (x-ray flux) enhancement for a 1ns flattop laser drive history. Simulated core self-emission x-ray histories also show earlier implosion times by 200-400ps, depending on the hohlraum case-to-capsule ratio and laser-entrance-hole size. Capsules filled with 10 or 50atm of deuterium (DD) are predicted to give in excess of 1010 neutrons in two-dimensional hohlraum simulations in the absence of mix, enabling DD burn history measurements for the first time in indirect-drive on Omega. Capsule designs with 50atm of DHe3 are also proposed to make use of proton slowing for independently verifying the drive benefits of rugby hohlraums. Scale-5/4 hohlraum designs are also introduced to provide further margin to potential laser-plasma-induced backscatter and hot-electron production.

Amendt, Peter; Cerjan, C.; Hinkel, D. E.; Milovich, J. L.; Park, H.-S.; Robey, H. F.

2008-01-01

352

Experimental studies on the optimization design of a low specific speed centrifugal pump  

NASA Astrophysics Data System (ADS)

Start your abstract here... For a low specific speed centrifugal pump with the requirement of high efficiency of 68% and non-overload power characteristics, series experimental studies, by matching 9 volutes with 19 impellers were done. By combining the former research results about the splitters and the non-overload theory in centrifugal pump, the theoretical conditions to achieve the property of non-overload in a centrifugal pump with splitters was analyzed, and formulas to estimate the maximum shaft power and its position are derived. Based on the requirement of high efficiency and non-overload, blade outlet angle ?2, blade outlet width b2, volute throat area Ft and the inlet diameter of splitters Di were chosen with three levels to design a normal L9 (34) orthogonal test scheme. Meanwhile, the optimized design scheme was determined, and corresponding test was done also, it demonstrates that the experiment purpose was reached, the design method to combine the splitters and non-overload theory is reasonable, which can get the property of high efficiency and non-overload.

Zhang, J. F.; Yuan, Y.; Yuan, S. Q.; Lu, W. G.; Yuan, J. P.

2012-11-01

353

Optimization and evaluation of clarithromycin floating tablets using experimental mixture design.  

PubMed

The purpose of the study was to prepare and evaluate clarithromycin (CLA) floating tablets using experimental mixture design for treatment of Helicobacter pylori provided by prolonged gastric residence time and controlled plasma level. Ten different formulations were generated based on different molecular weight of hypromellose (HPMC K100, K4M, K15M) by using simplex lattice design (a sub-class of mixture design) with Minitab 16 software. Sodium bicarbonate and anhydrous citric acid were used as gas generating agents. Tablets were prepared by wet granulation technique. All of the process variables were fixed. Results of cumulative drug release at 8th h (CDR 8th) were statistically analyzed to get optimized formulation (OF). Optimized formulation, which gave floating lag time lower than 15 s and total floating time more than 10 h, was analyzed and compared with target for CDR 8th (80%). A good agreement was shown between predicted and actual values of CDR 8th with a variation lower than 1%. The activity of clarithromycin contained optimizedformula against H. pylori were quantified using well diffusion agar assay. Diameters of inhibition zones vs. log10 clarithromycin concentrations were plotted in order to obtain a standard curve and clarithromycin activity. PMID:25272652

U?urlu, Timucin; Karaçiçek, U?ur; Rayaman, Erkan

2014-01-01

354

A Fundamental Study of Smoldering with Emphasis on Experimental Design for Zero-G  

NASA Technical Reports Server (NTRS)

A research program to study smoldering combustion with emphasis on the design of an experiment to be conducted in the space shuttle was conducted at the Department of Mechanical Engineering, University of California, Berkeley. The motivation of the research is the interest in smoldering both as a fundamental combustion problem and as a serious fire risk. Research conducted included theoretical and experimental studies that have brought considerable new information about smolder combustion, the effect that buoyancy has on the process, and specific information for the design of a space experiment. Experiments were conducted at normal gravity, in opposed and forward mode of propagation and in the upward and downward direction to determine the effect and range of influence of gravity on smolder. Experiments were also conducted in microgravity, in a drop tower and in parabolic aircraft flights, where the brief microgravity periods were used to analyze transient aspects of the problem. Significant progress was made on the study of one-dimensional smolder, particularly in the opposed-flow configuration. These studies provided enough information to design a small-scale space-based experiment that was successfully conducted in the Spacelab Glovebox in the June 1992 USML-1/STS-50 mission of the Space Shuttle Columbia.

Fernandez-Pello, Carlos; Pagni, Patrick J.

1995-01-01

355

Taguchi approach for co-gasification optimization of torrefied biomass and coal.  

PubMed

This study employs the Taguchi method to approach the optimum co-gasification operation of torrefied biomass (eucalyptus) and coal in an entrained flow gasifier. The cold gas efficiency is adopted as the performance index of co-gasification. The influences of six parameters, namely, the biomass blending ratio, oxygen-to-fuel mass ratio (O/F ratio), biomass torrefaction temperature, gasification pressure, steam-to-fuel mass ratio (S/F ratio), and inlet temperature of the carrier gas, on the performance of co-gasification are considered. The analysis of the signal-to-noise ratio suggests that the O/F ratio is the most important factor in determining the performance and the appropriate O/F ratio is 0.7. The performance is also significantly affected by biomass along with torrefaction, where a torrefaction temperature of 300°C is sufficient to upgrade eucalyptus. According to the recommended operating conditions, the values of cold gas efficiency and carbon conversion at the optimum co-gasification are 80.99% and 94.51%, respectively. PMID:23907063

Chen, Wei-Hsin; Chen, Chih-Jung; Hung, Chen-I

2013-09-01

356

Integrated design of Nb-based superalloys: Ab initio calculations, computational thermodynamics and kinetics, and experimental results  

Microsoft Academic Search

An optimal integration of modern computational tools and efficient experimentation is presented for the accelerated design of Nb-based superalloys. Integrated within a systems engineering framework, we have used ab initio methods along with alloy theory tools to predict phase stability of solid solutions and intermetallics to accelerate assessment of thermodynamic and kinetic databases enabling comprehensive predictive design of multicomponent multiphase

G. Ghosh; G. B. Olson

2007-01-01

357

A Novel Active Suspension Design Technique--Simulation and Experimental Huei Peng Ryan Strathearn A. Galip Ulsoy  

E-print Network

A Novel Active Suspension Design Technique--Simulation and Experimental Huei Peng Ryan Strathearn A for the design of active suspension systems is proposed in this paper. By defining virtual input signals, the dynamics of a quarter-car suspension system is transformed and becomes independent of vehicle parameters

Peng, Huei

358

Experimental Methods in Neuroscience: An Undergraduate Neuroscience Laboratory Course for Teaching Ethical Issues, Laboratory Techniques, Experimental Design, and Analysis  

NSDL National Science Digital Library

This article describes the development of a course which introduces students to issues of animal ethics, experimentation, and an Animal Care Facility. The experiments enable the students to gain confidence in collecting data, compiling large data sets, handling spreadsheets and graphing, applying appropriate statistics, and writing accurate and concise scientific reports in journal article format.

Adam C. Hall (Smith College; )

2003-11-01

359

Using decision analysis to determine optimal experimental design for monitoring sewer exfiltration with tracers.  

PubMed

The tracer methods developed to assess exfiltration from sewers in the European project APUSS (assessment of the performance of sewer systems) have a high degree of freedom with regard to the choice of tracer and the dosing strategy. These can lead to very different degrees of uncertainty in the measured exfiltration ratio. In this study, we demonstrate how to select an optimal experimental design using decision analysis, which accounts for this uncertainty and its associated costs. Although the results are site-specific, we can conclude generally that, when NaCl is used as the tracer, the accuracy of the exfiltration estimate is most sensitive to the amount of tracer used and the starting time of the experiment. PMID:17120646

Rieckermann, J; Borsuk, M E; Gujer, W

2006-01-01

360

An experimental design approach to the chemical characterisation of pectin polysaccharides extracted from Cucumis melo Inodorus.  

PubMed

Extracted pectins have been utilised in a number of applications in both the food and pharmaceutical industries where they are generally used as gelling agents, thickeners and stabilisers, although a number of pectins have been shown to be bioactive. These functional properties will depend upon extraction conditions. A statistical experimental design approach was used to study the effects of extraction conditions pH, time and temperature on pectins extracted from Cucumis melo Inodorus. The results show that the chemical composition is very sensitive to these conditions and that this has a great influence on for example the degree of branching. Higher temperatures, lower pHs and longer extraction times lead to a loss of the more acid labile arabinofuranose residues present on the pectin side chain. The fitting of regression equations relating yield and composition to extraction conditions can therefore lead to tailor-made pectins for specific properties and/or applications. PMID:25498647

Denman, Laura J; Morris, Gordon A

2015-03-01

361

Review of the International Thermonuclear Experimental Reactor (ITER) detailed design report  

SciTech Connect

Dr. Martha Krebs, Director, Office of Energy Research at the US Department of Energy (DOE), wrote to the Fusion Energy Sciences Advisory Committee (FESAC), in letters dated September 23 and November 6, 1996, requesting that FESAC review the International Thermonuclear Experimental Reactor (ITER) Detailed Design Report (DDR) and provide its view of the adequacy of the DDR as part of the basis for the United States decision to enter negotiations with the other interested Parties regarding the terms and conditions for an agreement for the construction, operations, exploitation and decommissioning of ITER. The letter from Dr. Krebs, referred to as the Charge Letter, provided context for the review and a set of questions of specific interest.

NONE

1997-04-18

362

Designing of the massive gas injection valve for the joint Texas experimental tokamak  

NASA Astrophysics Data System (ADS)

In order to mitigate the negative effects of the plasma disruption a massive gas injection (MGI) valve is designed for the joint Texas experimental tokamak. The MGI valve is based on the eddy-current repulsion mechanism. It has a fueling volume of 30 ml. The piston of the MGI valve is made by non-ferromagnetic material, so it can be installed close to the vacuum vessel which has a strong toroidal magnetic field. A diode is use to prevent current oscillation in the discharge circuit. The drive coil of the valve is installed outside the gas chamber. The opening characteristics and the gas flow of the MGI valve have been tested by a 60 l vacuum chamber. Owing to the large electromagnetic force the reaction time of the valve is shorter than 0.3 ms. Duration for the opening of the MGI valve is in the order of 10 ms.

Luo, Y. H.; Chen, Z. Y.; Tang, Y.; Wang, S. Y.; Ba, W. G.; Wei, Y. N.; Ma, T. K.; Huang, D. W.; Tong, R. H.; Yan, W.; Geng, P.; Shao, J.; Zhuang, G.

2014-08-01

363

Designing and implementing an experimental wireless mobile ad hoc networks testbed  

NASA Astrophysics Data System (ADS)

A very large number of simulation models have been developed to study ad hoc network architectures and protocols under many network scenarios, number of nodes, mobility rates, etc. However, fidelity of simulation results has always been a concern, especially when the protocols being studied are affected by the propagation and interference characteristics of the radio channels. This paper describes our experience in designing and implementing a MANET prototype system, Experimental Wireless Mobile Ad hoc Networks Testbed (EWMANT), in order to perform largescale, reproducible experiments. EWMANT aims at assessing several different protocols in a real-world environment instead of by simulation. It assists us with finding and evaluating a proper solution, showing the clear advantage of realworld implementations compared to simulations.

Li, Lixin; Dai, Guanzhong; Mu, Dejun; Zhang, Huisheng

2006-11-01

364

Designing of the massive gas injection valve for the joint Texas experimental tokamak.  

PubMed

In order to mitigate the negative effects of the plasma disruption a massive gas injection (MGI) valve is designed for the joint Texas experimental tokamak. The MGI valve is based on the eddy-current repulsion mechanism. It has a fueling volume of 30 ml. The piston of the MGI valve is made by non-ferromagnetic material, so it can be installed close to the vacuum vessel which has a strong toroidal magnetic field. A diode is use to prevent current oscillation in the discharge circuit. The drive coil of the valve is installed outside the gas chamber. The opening characteristics and the gas flow of the MGI valve have been tested by a 60 l vacuum chamber. Owing to the large electromagnetic force the reaction time of the valve is shorter than 0.3 ms. Duration for the opening of the MGI valve is in the order of 10 ms. PMID:25173266

Luo, Y H; Chen, Z Y; Tang, Y; Wang, S Y; Ba, W G; Wei, Y N; Ma, T K; Huang, D W; Tong, R H; Yan, W; Geng, P; Shao, J; Zhuang, G

2014-08-01

365

Steady state enzyme kinetics: experimental design and data analysis by microcomputer.  

PubMed

One of the most time-consuming, yet essential, operations involved in the steady state kinetic study of enzymes is the design and optimization of experimental conditions. A computer program was developed for the Sinclair ZX-81 (or TS-1000, 1500) microcomputer which will optimize substrate concentration for preliminary and subsequently more refined kinetic analysis of one, two or three substrate systems. This program also analyzes the data collected from these studies by linear regression, weighted linear regression or weighted non-linear regression. In addition to the above program several of the enzyme kinetic statistical analysis programs of Cleland (1979) have been translated from FORTRAN into BASIC and implemented on the ZX-81 and the TRS-80 model II. Inexpensive commercially available software was used to overcome the inability of the ZX-81 to read data files from magnetic tape making the data analysis programs easier to use. PMID:6548982

Roberts, B D; Ebner, K E

1984-01-01

366

Design and experimental verification of terahertz wideband filter based on double-layered metal hole arrays.  

PubMed

A terahertz wideband filter based on double layer metal hole arrays is designed in this paper. A metal hole array is perforated on a metal layer with a square array of circular air holes. The transmission characteristics of the electromagnetic waves through the metal hole array can be determined by the accumulation of in-phase scattering, spoof surface plasmon polaritons, and waveguide modes. The transmission spectrum is tuned by adding another identical layer metal hole array, and a wideband filter can be formed accordingly. Samples containing double-layered metal hole arrays were fabricated by micromachining technology. A wideband filter with center frequency located at 0.8 THz and FWHM reaching 400 GHz was experimentally achieved. PMID:22410895

Rao, Lei; Yang, Dongxiao; Zhang, Le; Li, Tao; Xia, Song

2012-03-01

367

Deployment of RFID in healthcare facilities-experimental design in MRI department.  

PubMed

Patient safety has become an important issue due to medical errors. Some health care systems use Radio Frequency Identification (RFID) to identify patients during medical procedures. However, the RFID data readability especially depends upon the environment, an investigation of data reliability and signal loss is essential to making an effective deployment plan. The operation of Magnetic Resonance Imaging (MRI) is the major source of electromagnetic interference in the hospital. Therefore, this research conducts an experimental design of reading performance considering various notable factors in the MRI department. In addition to the readability experiment, this paper also measures the efficiency and reliability of implementing RFID technology in the MRI department using a simulation approach and helps hospitals by providing the measured outcomes. PMID:22072278

Cheng, Chen-Yang; Chai, Jyh-Wen

2012-12-01

368

Optimization of ultrasonic-assisted extraction of cordycepin from Cordyceps militaris using orthogonal experimental design.  

PubMed

This study reports on the optimization of the extraction conditions of cordycepin from Cordyceps militaris by using ultrasonication. For this purpose, the orthogonal experimental design was used to investigate the effects of factors on the ultrasonic-assisted extraction (UAE). Four factors: extraction time (min), ethanol concentration (%), extraction temperature (°C) and extraction frequency (kHz), were studied. The results showed that the highest cordycepin yield of 7.04 mg/g (86.98% ± 0.23%) was obtained with an extraction time of 60 min, ethanol concentration of 50%, extraction temperature of 65 °C and extraction frequency of 56 kHz. It was found that the cordycepin extraction yield increased with the effect of ultrasonication during the extraction process. Therefore, UAE can be used as an alternative to conventional immersion extraction with respect to the recovery of cordycepin from C. militaris, with the advantages of shorter extraction time and reduced solvent consumption. PMID:25514223

Wang, Hsiu-Ju; Pan, Meng-Chun; Chang, Chao-Kai; Chang, Shu-Wei; Hsieh, Chang-Wei

2014-01-01

369

Design of an experimental configuration for studying the dynamic fragmentation of ceramics under impact  

NASA Astrophysics Data System (ADS)

To characterize the penetration resistance of a ceramic target during impact, it is necessary to take into consideration the mechanical behaviour of the fragmented ceramic. In the present work, a series of numerical simulations have been performed to design an experimental configuration named the "normal impact test". The aim of this configuration is to generate a strong fragmentation of the ceramic tile and to prevent any ejection of debris in order to analyse the fragmentation properties of the impacted ceramic. An anisotropic damage model has been used to perform these computations. The Weibull parameters that constitute input data of this model have been identified from four-point flexural tests performed on the so-called Hexoloy® silicon carbide. Finally, the numerical predictions are compared to the failure pattern of the fragmented ceramic.

Zinszner, J.-L.; Forquin, P.; Rossiquet, G.

2012-05-01

370

Visual analysis in single case experimental design studies: brief review and guidelines.  

PubMed

Visual analysis of graphic displays of data is a cornerstone of studies using a single case experimental design (SCED). Data are graphed for each participant during a study with trend, level, and stability of data assessed within and between conditions. Reliable interpretations of effects of an intervention are dependent on researchers' understanding and use of systematic procedures. The purpose of this paper is to provide readers with a rationale for visual analysis of data when using a SCED, a step-by-step guide for conducting a visual analysis of graphed data, as well as to highlight considerations for persons interested in using visual analysis to evaluate an intervention, especially the importance of collecting reliability data for dependent measures and fidelity of implementation of study procedures. PMID:23883189

Lane, Justin D; Gast, David L

2014-01-01

371

Using gray-based Taguchi method to construct multi-objective optimal model in super-resolution near-field photolithography.  

PubMed

This study integrated thermally induced super-resolution into near-field photolithography and conducted simulation and analysis on line segment fabrication. This technique involves passing a laser beam through an aluminum-plated optical fiber probe onto a thin film of indium (approximately 10 nm thick). The indium film opens a melted aperture narrower than the width of the laser beam, creating a melted region and a crystalline region. The difference in penetration rate between the two regions leads to the generation of thermally induced super-resolution. This paper proposes a combination of Taguchi method with gray relational analysis, in which S/N ratios obtained using the Taguchi method are converted into gray relational grades to identify an optimal combination of parameters capable of meeting multiple quality objectives. This optimal combination includes a probe aperture of 100 nm (A1), exposure energy/?m of 0.002nJ/?m (B2), development time of 60 s (C3), and indium film with a thickness of 7 nm (D1). The optimal parameters were (A1B2C3D1) for the gray relational analysis and (A1B1C1D1) for the Taguchi method. Results showed a negative improvement of -14.3% in line width from 126.2 (Taguchi method) to 144.2 nm (gray relational analysis). Working depth, however, showed a significantly improvement of 140.4% from 5.7 (Taguchi method) to 13.7 nm (gray relational analysis). The proposed approach resolves the conflicts that commonly occur among factor levels in Taguchi analysis under the requirements of multiple quality requirements. PMID:22766772

Yang, Ching-Been; Chiang, Hsiu-Lu

2013-01-01

372

Experimental design and optimization of raloxifene hydrochloride loaded nanotransfersomes for transdermal application  

PubMed Central

Raloxifene hydrochloride, a highly effective drug for the treatment of invasive breast cancer and osteoporosis in post-menopausal women, shows poor oral bioavailability of 2%. The aim of this study was to develop, statistically optimize, and characterize raloxifene hydrochloride-loaded transfersomes for transdermal delivery, in order to overcome the poor bioavailability issue with the drug. A response surface methodology experimental design was applied for the optimization of transfersomes, using Box-Behnken experimental design. Phospholipon® 90G, sodium deoxycholate, and sonication time, each at three levels, were selected as independent variables, while entrapment efficiency, vesicle size, and transdermal flux were identified as dependent variables. The formulation was characterized by surface morphology and shape, particle size, and zeta potential. Ex vivo transdermal flux was determined using a Hanson diffusion cell assembly, with rat skin as a barrier medium. Transfersomes from the optimized formulation were found to have spherical, unilamellar structures, with a homogeneous distribution and low polydispersity index (0.08). They had a particle size of 134±9 nM, with an entrapment efficiency of 91.00%±4.90%, and transdermal flux of 6.5±1.1 ?g/cm2/hour. Raloxifene hydrochloride-loaded transfersomes proved significantly superior in terms of amount of drug permeated and deposited in the skin, with enhancement ratios of 6.25±1.50 and 9.25±2.40, respectively, when compared with drug-loaded conventional liposomes, and an ethanolic phosphate buffer saline. Differential scanning calorimetry study revealed a greater change in skin structure, compared with a control sample, during the ex vivo drug diffusion study. Further, confocal laser scanning microscopy proved an enhanced permeation of coumarin-6-loaded transfersomes, to a depth of approximately160 ?M, as compared with rigid liposomes. These ex vivo findings proved that a raloxifene hydrochloride-loaded transfersome formulation could be a superior alternative to oral delivery of the drug. PMID:25246789

Mahmood, Syed; Taher, Muhammad; Mandal, Uttam Kumar

2014-01-01

373

Inferring the temperature dependence of population parameters: the effects of experimental design and inference algorithm.  

PubMed

Understanding and quantifying the temperature dependence of population parameters, such as intrinsic growth rate and carrying capacity, is critical for predicting the ecological responses to environmental change. Many studies provide empirical estimates of such temperature dependencies, but a thorough investigation of the methods used to infer them has not been performed yet. We created artificial population time series using a stochastic logistic model parameterized with the Arrhenius equation, so that activation energy drives the temperature dependence of population parameters. We simulated different experimental designs and used different inference methods, varying the likelihood functions and other aspects of the parameter estimation methods. Finally, we applied the best performing inference methods to real data for the species Paramecium caudatum. The relative error of the estimates of activation energy varied between 5% and 30%. The fraction of habitat sampled played the most important role in determining the relative error; sampling at least 1% of the habitat kept it below 50%. We found that methods that simultaneously use all time series data (direct methods) and methods that estimate population parameters separately for each temperature (indirect methods) are complementary. Indirect methods provide a clearer insight into the shape of the functional form describing the temperature dependence of population parameters; direct methods enable a more accurate estimation of the parameters of such functional forms. Using both methods, we found that growth rate and carrying capacity of Paramecium caudatum scale with temperature according to different activation energies. Our study shows how careful choice of experimental design and inference methods can increase the accuracy of the inferred relationships between temperature and population parameters. The comparison of estimation methods provided here can increase the accuracy of model predictions, with important implications in understanding and predicting the effects of temperature on the dynamics of populations. PMID:25558365

Palamara, Gian Marco; Childs, Dylan Z; Clements, Christopher F; Petchey, Owen L; Plebani, Marco; Smith, Matthew J

2014-12-01

374

Inferring the temperature dependence of population parameters: the effects of experimental design and inference algorithm  

PubMed Central

Understanding and quantifying the temperature dependence of population parameters, such as intrinsic growth rate and carrying capacity, is critical for predicting the ecological responses to environmental change. Many studies provide empirical estimates of such temperature dependencies, but a thorough investigation of the methods used to infer them has not been performed yet. We created artificial population time series using a stochastic logistic model parameterized with the Arrhenius equation, so that activation energy drives the temperature dependence of population parameters. We simulated different experimental designs and used different inference methods, varying the likelihood functions and other aspects of the parameter estimation methods. Finally, we applied the best performing inference methods to real data for the species Paramecium caudatum. The relative error of the estimates of activation energy varied between 5% and 30%. The fraction of habitat sampled played the most important role in determining the relative error; sampling at least 1% of the habitat kept it below 50%. We found that methods that simultaneously use all time series data (direct methods) and methods that estimate population parameters separately for each temperature (indirect methods) are complementary. Indirect methods provide a clearer insight into the shape of the functional form describing the temperature dependence of population parameters; direct methods enable a more accurate estimation of the parameters of such functional forms. Using both methods, we found that growth rate and carrying capacity of Paramecium caudatum scale with temperature according to different activation energies. Our study shows how careful choice of experimental design and inference methods can increase the accuracy of the inferred relationships between temperature and population parameters. The comparison of estimation methods provided here can increase the accuracy of model predictions, with important implications in understanding and predicting the effects of temperature on the dynamics of populations. PMID:25558365

Palamara, Gian Marco; Childs, Dylan Z; Clements, Christopher F; Petchey, Owen L; Plebani, Marco; Smith, Matthew J

2014-01-01

375

Study of formulation variables influencing the drug release rate from matrix tablets by experimental design.  

PubMed

Experimental design was utilized to simultaneously investigate the effect of varying the type of diluent (insoluble Calcium phosphate or water-soluble arabic gum) and the diluent/matrix ratio on the drug release behaviour from both lipophilic (glyceryl behenate, Compritol) or hydrophilic (hydroxypropylmethylcellulose) matrix tablets. Ketoprofen, theophylline and sodium sulphadiazine were selected as model drugs on the basis of their respectively very low, medium and high water-solubility, in order to evaluate the influence of this parameter as well. The selected response variables were the dissolution efficiency (i.e. the area under the dissolution curve) after one and six hours and the time necessary to dissolve 10% drug. Tablets obtained by direct compression of drug-diluent-matrix ternary mixtures prepared according to the experimental plan provided for by an asymmetric screening matrix, were tested for drug release properties using a USP paddle apparatus. Graphic analysis of the effects allowed identification, for each examined drug, of the formulation factors active on the selected responses and determination of the proper level of the variables to be selected for the response improvement. The different results obtained with the three examined drugs pointed out the role of the drug solubility in determining the influence of formulation parameters on drug release rate from matrix tablets. PMID:16154333

Furlanetto, Sandra; Cirri, Marzia; Maestrelli, Francesca; Corti, Giovanna; Mura, Paola

2006-01-01

376

Chemical morphogenesis: recent experimental advances in reaction-diffusion system design and control.  

PubMed

In his seminal 1952 paper, Alan Turing predicted that diffusion could spontaneously drive an initially uniform solution of reacting chemicals to develop stable spatially periodic concentration patterns. It took nearly 40 years before the first two unquestionable experimental demonstrations of such reaction-diffusion patterns could be made in isothermal single phase reaction systems. The number of these examples stagnated for nearly 20 years. We recently proposed a design method that made their number increase to six in less than 3 years. In this report, we formally justify our original semi-empirical method and support the approach with numerical simulations based on a simple but realistic kinetic model. To retain a number of basic properties of real spatial reactors but keep calculations to a minimal complexity, we introduce a new way to collapse the confined spatial direction of these reactors. Contrary to similar reduced descriptions, we take into account the effect of the geometric size in the confinement direction and the influence of the differences in the diffusion coefficient on exchange rates of species with their feed environment. We experimentally support the method by the observation of stationary patterns in red-ox reactions not based on oxihalogen chemistry. Emphasis is also brought on how one of these new systems can process different initial conditions and memorize them in the form of localized patterns of different geometries. PMID:23919126

Szalai, István; Cuiñas, Daniel; Takács, Nándor; Horváth, Judit; De Kepper, Patrick

2012-08-01

377

Chemical morphogenesis: recent experimental advances in reaction–diffusion system design and control  

PubMed Central

In his seminal 1952 paper, Alan Turing predicted that diffusion could spontaneously drive an initially uniform solution of reacting chemicals to develop stable spatially periodic concentration patterns. It took nearly 40 years before the first two unquestionable experimental demonstrations of such reaction–diffusion patterns could be made in isothermal single phase reaction systems. The number of these examples stagnated for nearly 20 years. We recently proposed a design method that made their number increase to six in less than 3 years. In this report, we formally justify our original semi-empirical method and support the approach with numerical simulations based on a simple but realistic kinetic model. To retain a number of basic properties of real spatial reactors but keep calculations to a minimal complexity, we introduce a new way to collapse the confined spatial direction of these reactors. Contrary to similar reduced descriptions, we take into account the effect of the geometric size in the confinement direction and the influence of the differences in the diffusion coefficient on exchange rates of species with their feed environment. We experimentally support the method by the observation of stationary patterns in red-ox reactions not based on oxihalogen chemistry. Emphasis is also brought on how one of these new systems can process different initial conditions and memorize them in the form of localized patterns of different geometries. PMID:23919126

Szalai, István; Cuiñas, Daniel; Takács, Nándor; Horváth, Judit; De Kepper, Patrick

2012-01-01

378

Spray drying formulation of albendazole microspheres by experimental design. In vitro-in vivo studies.  

PubMed

Abstract Both an experimental design and optimization techniques were carried out for the development of chitosan-pectin-carboxymethylcellulose microspheres to improve the oral absorption of albendazole as a model drug. The effect of three different factors (chitosan, pectin and carboxy methyl cellulose concentrations) was studied on five responses: yield, morphology, dissolution rate at 30 and 60?min, and encapsulation efficiency of the microspheres. During the screening phase, the factors were evaluated in order to identify those which exert a significant effect. Simultaneous multiple response optimizations were then used to find out experimental conditions where the system shows the most adequate results. The optimal conditions were found to be: chitosan concentration, 1.00% w/v, pectin concentration 0.10% w/v and carboxymethylcellulose concentration 0.20% w/v. The bioavailability of the loaded drug in the optimized microspheres was evaluated in Wistar rats which showed an area under curve (AUC) almost 10 times higher than the pure drug. PMID:24237328

García, Agustina; Leonardi, Darío; Piccirilli, Gisela N; Mamprin, María E; Olivieri, Alejandro C; Lamas, María C

2015-02-01

379

Designing a SCAR molecular marker for monitoring Trichoderma cf. harzianum in experimental communities.  

PubMed

Several species of the fungal genus Trichoderma establish biological interactions with various micro- and macro-organisms. Some of these interactions are relevant in ecological terms and in biotechnological applications, such as biocontrol, where Trichoderma could be considered as an invasive species that colonizes a recipient community. The success of this invasion depends on multiple factors, which can be assayed using experimental communities as study models. Therefore, the aim of this work is to develop a species-specific sequence-characterized amplified region (SCAR) marker to monitor the colonization and growth of T. cf. harzianum when it invades experimental communities. For this study, 16 randomly amplified polymorphic DNA (RAPD) primers of 10-mer were used to generate polymorphic patterns, one of which generated a band present only in strains of T. cf. harzianum. This band was cloned, sequenced, and five primers of 20-23 mer were designed. Primer pairs 2F2/2R2 and 2F2/2R3 successfully and specifically amplified fragments of 278 and 448 bp from the T. cf. harzianum BpT10a strain DNA, respectively. Both primer pairs were also tested against the DNA from 14 strains of T. cf. harzianum and several strains of different fungal genera as specificity controls. Only the DNA from the strains of T. cf. harzianum was successfully amplified. Moreover, primer pair 2F2/2R2 was assessed by quantitative real-time polymerase chain reaction (PCR) using fungal DNA mixtures and DNA extracted from fungal experimental communities as templates. T. cf. harzianum was detectable even when as few as 100 copies of the SCAR marker were available or even when its population represented only 0.1% of the whole community. PMID:25367789

Pérez, Gabriel; Verdejo, Valentina; Gondim-Porto, Clarissa; Orlando, Julieta; Carú, Margarita

2014-11-01

380

Designing a SCAR molecular marker for monitoring Trichoderma cf. harzianum in experimental communities* #  

PubMed Central

Several species of the fungal genus Trichoderma establish biological interactions with various micro- and macro-organisms. Some of these interactions are relevant in ecological terms and in biotechnological applications, such as biocontrol, where Trichoderma could be considered as an invasive species that colonizes a recipient community. The success of this invasion depends on multiple factors, which can be assayed using experimental communities as study models. Therefore, the aim of this work is to develop a species-specific sequence-characterized amplified region (SCAR) marker to monitor the colonization and growth of T. cf. harzianum when it invades experimental communities. For this study, 16 randomly amplified polymorphic DNA (RAPD) primers of 10-mer were used to generate polymorphic patterns, one of which generated a band present only in strains of T. cf. harzianum. This band was cloned, sequenced, and five primers of 20–23 mer were designed. Primer pairs 2F2/2R2 and 2F2/2R3 successfully and specifically amplified fragments of 278 and 448 bp from the T. cf. harzianum BpT10a strain DNA, respectively. Both primer pairs were also tested against the DNA from 14 strains of T. cf. harzianum and several strains of different fungal genera as specificity controls. Only the DNA from the strains of T. cf. harzianum was successfully amplified. Moreover, primer pair 2F2/2R2 was assessed by quantitative real-time polymerase chain reaction (PCR) using fungal DNA mixtures and DNA extracted from fungal experimental communities as templates. T. cf. harzianum was detectable even when as few as 100 copies of the SCAR marker were available or even when its population represented only 0.1% of the whole community. PMID:25367789

Pérez, Gabriel; Verdejo, Valentina; Gondim-Porto, Clarissa; Orlando, Julieta; Carú, Margarita

2014-01-01

381

Engineering Design Education Program for Graduate School  

NASA Astrophysics Data System (ADS)

The new educational methods of engineering design have attempted to improve mechanical engineering education for graduate students in a way of the collaboration in education of engineer and designer. The education program is based on the lecture and practical exercises concerning the product design, and has engineering themes and design process themes, i.e. project management, QFD, TRIZ, robust design (Taguchi method) , ergonomics, usability, marketing, conception etc. At final exercise, all students were able to design new product related to their own research theme by applying learned knowledge and techniques. By the method of engineering design education, we have confirmed that graduate students are able to experience technological and creative interest.

Ohbuchi, Yoshifumi; Iida, Haruhiko

382

Design of the Grimethorpe Experimental Facility as of March 1981: a technical report  

SciTech Connect

The Experimental Pressurized Fluidized Bed Combustor, which has been built as an extension to the National Coal Board Power Station, which is adjacent to Grimethorpe Colliery, Yorkshire, England, is described in this report. The Governments of the United Kingdom, the United States of America and the Federal Republic of Germany, under the auspices of the International Energy Agency, have agreed to share equally between them the costs of building and operating the plant. Control of the project was vested in an Executive Committee consisting of one representative of each Government with all decisions requiring unanimity. The actual operation of the project was vested in an Operating Agent, NCB (IEA Services) Ltd., a wholly owned subsidiary of the National Coal Board. The Implementing Agreement envisages a seven year project to be executed in four stages: (1) Procurement of Design Study with accompanying tender documents. (2) Tendering for construction of the Plant; study of appraisal of tenders. (3) Construction and acceptance of the Plant. (4) Operation of the Plant. The project is now towards the end of Stage 3. Construction has been completed and commissioning is in progress to prepare the plant for the start of the operational phase in Autumn 1981. Because of the confidentiality of much of the design information, for the purposes of this report technical descriptions have been confined to that of a general appraisal.

Not Available

1984-06-01

383

Final Design and Experimental Validation of the Thermal Performance of the LHC Lattice Cryostats  

NASA Astrophysics Data System (ADS)

The recent commissioning and operation of the LHC String 2 have given a first experimental validation of the global thermal performance of the LHC lattice cryostat at nominal cryogenic conditions. The cryostat designed to minimize the heat inleak from ambient temperature, houses under vacuum and thermally protects the cold mass, which contains the LHC twin-aperture superconducting magnets operating at 1.9 K in superfluid helium. Mechanical components linking the cold mass to the vacuum vessel, such as support posts and insulation vacuum barriers are designed with efficient thermalisations for heat interception to minimise heat conduction. Heat inleak by radiation is reduced by employing multilayer insulation (MLI) wrapped around the cold mass and around an aluminium thermal shield cooled to about 60 K. Measurements of the total helium vaporization rate in String 2 gives, after substraction of supplementary heat loads and end effects, an estimate of the total thermal load to a standard LHC cell (107 m) including two Short Straight Sections and six dipole cryomagnets. Temperature sensors installed at critical locations provide a temperature mapping which allows validation of the calculated and estimated thermal performance of the cryostat components, including efficiency of the heat interceptions.

Bourcey, N.; Capatina, O.; Parma, V.; Poncet, A.; Rohmig, P.; Serio, L.; Skoczen, B.; Tock, J.-P.; Williams, L. R.

2004-06-01

384

How to design in situ studies: an evaluation of experimental protocols  

PubMed Central

Objectives Designing in situ models for caries research is a demanding procedure, as both clinical and laboratory parameters need to be incorporated in a single study. This study aimed to construct an informative guideline for planning in situ models relevant to preexisting caries studies. Materials and Methods An electronic literature search of the PubMed database was performed. A total 191 of full articles written in English were included and data were extracted from materials and methods. Multiple variables were analyzed in relation to the publication types, participant characteristics, specimen and appliance factors, and other conditions. Frequencies and percentages were displayed to summarize the data and the Pearson's chi-square test was used to assess a statistical significance (p < 0.05). Results There were many parameters commonly included in the majority of in situ models such as inclusion criteria, sample sizes, sample allocation methods, tooth types, intraoral appliance types, sterilization methods, study periods, outcome measures, experimental interventions, etc. Interrelationships existed between the main research topics and some parameters (outcome measures and sample allocation methods) among the evaluated articles. Conclusions It will be possible to establish standardized in situ protocols according to the research topics. Furthermore, data collaboration from comparable studies would be enhanced by homogeneous study designs. PMID:25110639

Sung, Young-Hye; Kim, Hae-Young; Son, Ho-Hyun

2014-01-01

385

Experimental design approach for identification of the factors influencing the ?-radiolysis of ion exchange resins  

NASA Astrophysics Data System (ADS)

Gamma radiolysis was investigated on a nuclear grade mixed bed ion exchange resin and its pure components under different irradiation conditions. Screening designs were performed to identify the factors influencing gas production after their ?-radiolysis and to compare their ?-degradation stability. Only hydrogen and trimethylamine quantities were considered as the response in the experimental designs. The other detected gases and water-soluble products were used to improve the resins degradation. Aerobic irradiation atmosphere decreased the H2g production of AmbOH, MB400, and amines. The water presence increased the H2g quantities for AmbH and decreased those for MB400 resin. Liquid water had no effect on H2g production from AmbOH but was favorable to increased amine production. The H2g production of AmbH increased with the absorbed dose that had little effect on the AmbOH resin. No impact of dose on the H2g production was detected for MB400 that appeared to be less degraded.

Rébufa, C.; Traboulsi, A.; Labed, V.; Dupuy, N.; Sergent, M.

2015-01-01

386

Thermal control for space microelectronic equipment via pyroelectric material: Design, characterisation and experimental campaign  

NASA Astrophysics Data System (ADS)

In the last decades the development of new satellite platforms from a smaller to a bigger size goes in parallel with the development of the microelectronics equipment boarded on. Avionics, control systems and payloads equipment exploit the microelectronics in order to reduce the overall dimensions and masses and to increase the performances of each unit for the improvement of goals in each mission. A larger use of electronic elements with the relevant components increases the importance of a carefully equipment designed under different points of view. One of them is the thermal management. It is well known that the Joule Effect causes the heat overstocking which in turn reduces the efficiency of the electronic devices and increases the difficulties to manage the thermal power budget on board. A new design philosophy sees a possibility for a simpler and a more efficient thermal control on the use of the pyroelectric materials. Pyroelectrics are a "special" class of materials that demonstrates a spontaneous capacity to convert thermal fluxes in electrical charge and if applied on a "passive" structure they can "actively" reduce the heat overstocking. The electrical charge could be eventually stored for different purposes such as for instance the auto-feeding, or better the energy harvesting. With the reduction of the temperature of each component, and consequently with the reduction of the heat flux that flows through microelectronics, better efficiency and better performances are ensured. In this way the reliability is increased and the goals of the mission could be achieved easier and easier. In this paper the design of a thermal rig made up of pyroelectric devices and dummy electronics components in order to verify the thermo-electric conversion is presented. Furthermore an experimental campaign has been performed to validate the technology here introduced and the relevant results presented. In particular the characterisation of a typical aerospace pyroelectric material via scanning electron microscope (SEM) and a semi-quantitative analysis will be discussed. In order to verify the trustworthiness of the experimental campaign the results will be compared with the ones coming from an in-house-developed numerical code.

Monti, Riccardo; Gasbarri, Paolo; Lecci, Umberto

2012-12-01

387

Multi-objective optimization design and experimental investigation of centrifugal fan performance  

NASA Astrophysics Data System (ADS)

Current studies of fan performance optimization mainly focus on two aspects: one is to improve the blade profile, and another is only to consider the influence of single impeller structural parameter on fan performance. However, there are few studies on the comprehensive effect of the key parameters such as blade number, exit stagger angle of blade and the impeller outlet width on the fan performance. The G4-73 backward centrifugal fan widely used in power plants is selected as the research object. Based on orthogonal design and BP neural network, a model for predicting the centrifugal fan performance parameters is established, and the maximum relative errors of the total pressure and efficiency are 0.974% and 0.333%, respectively. Multi-objective optimization of total pressure and efficiency of the fan is conducted with genetic algorithm, and the optimum combination of impeller structural parameters is proposed. The optimized parameters of blade number, exit stagger angle of blade and the impeller outlet width are seperately 14, 43.9°, and 21 cm. The experiments on centrifugal fan performance and noise are conducted before and after the installation of the new impeller. The experimental results show that with the new impeller, the total pressure of fan increases significantly in total range of the flow rate, and the fan efficiency is improved when the relative flow is above 75%, also the high efficiency area is broadened. Additionally, in 65% -100% relative flow, the fan noise is reduced. Under the design operating condition, total pressure and efficiency of the fan are improved by 6.91% and 0.5%, respectively. This research sheds light on the considering of comprehensive effect of impeller structrual parameters on fan performance, and a new impeller can be designed to satisfy the engineering demand such as energy-saving, noise reduction or solving air pressure insufficiency for power plants.

Zhang, Lei; Wang, Songling; Hu, Chenxing; Zhang, Qian

2013-11-01

388

Application of Plackett-Burman experimental design and Doehlert design to evaluate nutritional requirements for xylanase production by Alternaria mali ND-16.  

PubMed

The objective of this study was to use statistically based experimental designs for the optimization of xylanase production from Alternaria mali ND-16. Ten components in the medium were screened for nutritional requirements. Three nutritional components, including NH(4)Cl, urea, and MgSO(4), were identified to significantly affect the xylanase production by using the Plackett-Burman experimental design. These three major components were subsequently optimized using the Doehlert experimental design. By using response surface methodology and canonical analysis, the optimal concentrations for xylanase production were: NH(4)Cl 11.34 g L(-1), urea 1.26 g L(-1), and MgSO(4) 0.98 g L(-1). Under these optimal conditions, the xylanase activity from A. mali ND-16 reached 30.35 U mL(-1). Verification of the optimization showed that xylanase production of 31.26 U mL(-1) was achieved. PMID:17846761

Li, Yin; Liu, Zhiqiang; Cui, Fengjie; Liu, Zhisheng; Zhao, Hui

2007-11-01

389

Concurrent process tolerance design based on minimum product manufacturing cost and quality loss  

Microsoft Academic Search

In a concurrent design environment, a robust optimum method is presented to directly determine the process tolerances from multiple correlated critical tolerances in an assembly. With given distributions of multiple critical assembly dimensions, the Taguchi quadric quality loss function is first derived. The quality loss is then expressed as the function of pertinent process tolerances. A nonlinear optimal model is

M. F. Huang; Y. R. Zhong; Z. G. Xu

2005-01-01

390

Design and Experimental Test Plan for Hybrid Sulfur Single Cell Pressurized Electrolyzer  

SciTech Connect

The Hybrid Sulfur (HyS) process is one of the leading thermochemical cycles being studied as part of the DOE Nuclear Hydrogen Initiative (NHI). SRNL is conducting analyses and research and development for the Department of Energy on the HyS process. A conceptual design report and development plan for the HyS process was issued on April 1, 2005 [Buckner, et. al., 2005] , and a report on atmospheric testing of a sulfur dioxide depolarized electrolyzer (SDE), a major component of the HyS process, was issued on August 1, 2005 [Steimke, 2005]. The purpose of this report is to document work related to the design and experimental test plan for a pressurized SDE. Pressurized operation of the SDE is a key requirement for development of an efficient and cost-effective HyS process. The HyS process, a hybrid thermochemical cycle proposed and investigated in the 1970s and early 1980s by Westinghouse Electric Corporation, is a high priority candidate for NHI due to the potential for high efficiency and its relatively high level of technical maturity. It was demonstrated in laboratory experiments by Westinghouse in 1978. Process improvements and component advancements that build on that work are being pursued. One of the objectives of the current work is to develop the SDE in order to permit the demonstration of a closed-loop laboratory model of the HyS process. The heart of the HyS process for generating hydrogen is a bank of electrolyzers incorporating sulfur dioxide depolarized anodes. SRNL planned, designed, built and operated a facility for testing single cell electrolyzers at ambient temperature and near atmospheric pressure during the spring and summer of 2005. The major contribution of the SRNL work was the establishment of the proof-of-concept for utilizing the proton-exchange-membrane (PEM) cell design for the SDE operation. Since PEM cells are being extensively developed for automotive fuel cell use, they offer significant potential for cost-effective application for the HyS Process. This report discusses the modifications necessary to the existing SRNL sulfur dioxide depolarized electrolyzer test facility to allow testing at up to 80 C and 90 psig. Because of the need for significant additional equipment and the ability to infer performance results to higher pressures, it recommends delaying further modifications to support testing at up to 300 psig (the commercial goal) until other, higher priority technical issues are addressed. These issues include membrane material selection, component designs, catalyst type and loading, etc. The factors and rationale that should be considered in developing and executing a detailed test matrix for pressurized operation are also discussed. In addition, an electrolyzer assembly design has been developed to allow the testing of different Membrane Electrode Assemblies (MEA's) as part of the planned FY06 HyS Development Program to complete selection of component design specifications for the HyS electrolyzer. MEA's are used in PEM cells to allow intimate contact and minimal resistance between the electrodes and the electrolyte layer. The pressurized electrolyzer assembly presented in this report will facilitate rapid change-out and testing of various MEA designs as part of the electrolyzer development effort.

Steeper, T. J.; Steimke, J. L.

2005-09-01

391

A methodology for evacuation design for urban areas: theoretical aspects and experimentation  

NASA Astrophysics Data System (ADS)

This paper proposes an unifying approach for the simulation and design of a transportation system under conditions of incoming safety and/or security. Safety and security are concerned with threats generated by very different factors and which, in turn, generate emergency conditions, such as the 9/11, Madrid and London attacks, the Asian tsunami, and the Katrina hurricane; just considering the last five years. In transportation systems, when exogenous events happen and there is a sufficient interval time between the instant when the event happens and the instant when the event has effect on the population, it is possible to reduce the negative effects with the population evacuation. For this event in every case it is possible to prepare with short and long term the evacuation. For other event it is possible also to plan the real time evacuation inside the general risk methodology. The development of models for emergency conditions in transportation systems has not received much attention in the literature. The main findings in this area are limited to only a few public research centres and private companies. In general, there is no systematic analysis of the risk theory applied in the transportation system. Very often, in practice, the vulnerability and exposure in the transportation system are considered as similar variables, or in other worse cases the exposure variables are treated as vulnerability variables. Models and algorithms specified and calibrated in ordinary conditions cannot be directly applied in emergency conditions under the usual hypothesis considered. This paper is developed with the following main objectives: (a) to formalize the risk problem with clear diversification (for the consequences) in the definition of the vulnerability and exposure in a transportation system; thus the book offers improvements over consolidated quantitative risk analysis models, especially transportation risk analysis models (risk assessment); (b) to formalize a system of models for evacuation simulation; (c) to calibrate and validate system of model for evacuation simulation from a real experimentation. In relation to the proposed objectives in this paper: (a) a general framework about risk analysis is reported in the first part, with specific methods and models to analyze urban transportation system performances in emergency conditions when exogenous phenomena occur and for the specification of the risk function; (b) a formulation of the general evacuation problem in the standard simulation context of "what if" approach is specified in the second part with reference to the model considered for the simulation of transportation system in ordinary condition; (c) a set of models specified in the second part are calibrated and validated from a real experimentation in the third part. The experimentation was developed in the central business district of an Italian village and about 1000 inhabitants were evacuated, in order to construct a complete data-base. Our experiment required that socioeconomic information (population, number employed, public buildings, schools, etc.) and ?transport supply characteristics (infrastructures, etc.) be measured before and during experimentation. The real data of evacuation were recorded with 30 video cameras for laboratory analysis. The results are divided into six strictly connected tasks: Demand models; Supply and supply-demand interaction models for users; Simulation of refuge areas for users; Design of path choice models for emergency vehicles; Pedestrian outflow models in a building; Planning process and guidelines.

Russo, F.; Vitetta, A.

2009-04-01

392

Rating the methodological quality of single-subject designs and n-of-1 trials: Introducing the Single-Case Experimental Design (SCED) Scale  

Microsoft Academic Search

Rating scales that assess methodological quality of clinical trials provide a means to critically appraise the literature. Scales are currently available to rate randomised and non-randomised controlled trials, but there are none that assess single-subject designs. The Single-Case Experimental Design (SCED) Scale was developed for this purpose and evaluated for reliability. Six clinical researchers who were trained and experienced in

Robyn L Tate; Skye Mcdonald; Michael Perdices; Leanne Togher; Regina Schultz; Sharon Savage

2008-01-01

393

Formulation and characterization of boanmycin-loaded liposomes prepared by pH gradient experimental design.  

PubMed

This study reports the development of a novel liposomal formulation containing boanmycin (BAM) by the pH-gradient, spherical symmetric experimental design. DSC was used to elucidate the thermotropic transition of the soybean egg phosphatidylcholine (EPCS) bilayers. The DSC analysis showed that the incorporation of cholesterol into the EPCS bilayers caused a reduction in the cooperativity of the bilayer phase transition, leading to a dense and more stable structure. To further explore the possibility of the facilitated molecular interaction between BAM and lipids, the effective chemical shift anisotropy (??) of EPCS was measured by (31)P-NMR spectroscopy in the presence and absence of BAM at 25 °C. The results revealed that the amino group of BAM interacted with the hydrophilic head group of EPCS by electrostatic attraction. Effects of the lipid concentration, pH of the outside buffer and incubation temperature on the encapsulation efficiency of the liposomes were investigated by the spherical symmetric design. Multiple nonlinear regression and second-order polynomial model were fitted to the data, and the resulting equations were used to produce the three dimensional response graphs. The actual response values were in good agreement with the predicted values calculated by the visual FoxPro software. To determine the plasma pharmacokinetics and tissue distribution characteristics of BAM, mice were i.v. injected with BAM-loaded liposomes and the commercial injection solution. The BAM-loaded liposomes exhibited significantly different t(1/2), CL and AUC in plasma and tissues. The MTT assay showed that the BAM-loaded liposomes effectively inhibited the cell proliferation by inducing apoptosis of HepG2 cells in a dose- and time-dependent manner. Compared to the control group, the BAM-loaded liposomes induced marked apoptotic morphologic alterations, including cell shrinkage and granular apoptotic bodies. PMID:22283679

Liu, Yu; Yoo, Sun Dong; Li, Li; Fang, Liang; Wen, Ziyi; Li, Tiefu

2012-02-01

394

Design of a magnetic shielding system for the time of flight enhanced diagnostics neutron spectrometer at Experimental Advanced Superconducting Tokamak.  

PubMed

The novel neutron spectrometer TOFED (Time of Flight Enhanced Diagnostics), comprising 90 individual photomultiplier tubes coupled with 85 plastic scintillation detectors through light guides, has been constructed and installed at Experimental Advanced Superconducting Tokamak. A dedicated magnetic shielding system has been constructed for TOFED, and is designed to guarantee the normal operation of photomultiplier tubes in the stray magnetic field leaking from the tokamak device. Experimental measurements and numerical simulations carried out employing the finite element method are combined to optimize the design of the magnetic shielding system. The system allows detectors to work properly in an external magnetic field of 200 G. PMID:25430242

Cui, Z Q; Chen, Z J; Xie, X F; Peng, X Y; Hu, Z M; Du, T F; Ge, L J; Zhang, X; Yuan, X; Xia, Z W; Hu, L Q; Zhong, G Q; Lin, S Y; Wan, B N; Fan, T S; Chen, J X; Li, X Q; Zhang, G H

2014-11-01

395

Design and optimization of an experimental bioregenerative life support system with higher plants and silkworms  

NASA Astrophysics Data System (ADS)

The conceptual scheme of an experimental bioregenerative life support system (BLSS) for planetary exploration was designed, which consisted of four elements - human metabolism, higher plants, silkworms and waste treatment. 15 kinds of higher plants, such as wheat, rice, soybean, lettuce, mulberry, et al., were selected as regenerative component of BLSS providing the crew with air, water, and vegetable food. Silkworms, which producing animal nutrition for crews, were fed by mulberry-leaves during the first three instars, and lettuce leaves last two instars. The inedible biomass of higher plants, human wastes and silkworm feces were composted into soil like substrate, which can be reused by higher plants cultivation. Salt, sugar and some household material such as soap, shampoo would be provided from outside. To support the steady state of BLSS the same amount and elementary composition of dehydrated wastes were removed periodically. The balance of matter flows between BLSS components was described by the system of algebraic equations. The mass flows between the components were optimized by EXCEL spreadsheets and using Solver. The numerical method used in this study was Newton's method.

Hu, Enzhu; Bartsev, Sergey I.; Zhao, Ming; Liu, Professor Hong

396

Standardization of Experimental Design for Crop Cultivation in Life Support Systems for Space Exploration  

NASA Astrophysics Data System (ADS)

Due to logistical challenges, long-term human space exploration missions require a life support system capable of regenerating all the essentials for survival. Higher plants can be utilized to provide a continuous supply of fresh food, fresh air, and clean water for humans. The extensive work performed have shown that higher plants are able to adapt to space conditions in low Earth orbit, at least from one generation from seed to seed. Since the hardware has turned out to be of great importance for the results in microgravity research, full environmental monitoring and control must be the standard for future experiments. Selecting a few model plants, including crop plants for life support, would further increase the comparability between studies. The European Space Agency (ESA) has developed the Micro-Ecological Life Support System Alternative (MELiSSA) program to develop a closed regenerative life support system, based on micro-organisms and higher plants, with continuous recycling of resources. In the present study, recommended standardization of the experimental design for future scientific work assessing the effects of graded gravity on plant metabolism will be presented. This includes the environmental conditions required for cultivation of the selected MEliSSA species (wheat, bread wheat, soybean and potato), as well as guidelines for sowing, plant handling and analysis. Keywords: microgravity; magnetic field; radiation; MELiSSA; Moon; Mars.

Wolff, Silje Aase; Coelho, Liz Helena; Karoliussen, Irene; Kittang Jost, Ann-Iren

397

Outdoor experimental ponds (mesocosms) designed for long-term ecotoxicological studies in aquatic environment.  

PubMed

Outdoor artificial ponds (mesocosms) of 12 m3 were designed for long-term ecotoxicological studies. Sediment, macrophytes (Typha angustifolia and Elodea canadensis), and free and caged freshwater snails [Lymnaea palustris (Müller)] and wood lice (Asellus aquaticus L.) were collected in nearby natural ecosystems and introduced in the mesocosms. Sixty goldfish (Carassius auratus L.) were caged in each pond. Introduced species developed and reproduced in every mesocosm. Animal species (mainly insects and amphibians) spontaneously colonized the ponds, developed, and reproduced. The resulting communities qualitatively resemble those living in natural lentic systems in the surrounding area. Homogenity in physical and chemical conditions and in abundance of phytoplanktonic, periphytic, and macroinvertebrate communities between the different mesocosms was assessed during the stabilization period (8 months). Except for periphyton biomass, no divergent evolution was observed between the ponds. Mesocosm water was slightly eutrophic, alkaline (mean pH: 8.47 +/- 0.09), and moderately hard and mineralized. The homogenous and realistic environmental conditions and high ecological representativity of the outdoor experimental ponds were suitable for extensive ecotoxicological studies. Considerations on the choice and origin of introduced species and on possible interactive effects of the transfer of organisms from natural environments, maintainance conditions, and pollutant exposure are discussed. PMID:8812177

Caquet, T; Lagadic, L; Jonot, O; Baturo, W; Kilanda, M; Simon, P; Le Bras, S; Echaubard, M; Ramade, F

1996-07-01

398

Molecular design, synthesis and physical properties of novel Cytisine-derivatives - Experimental and theoretical study  

NASA Astrophysics Data System (ADS)

The paper presented a comprehensive theoretical and experimental study on the molecular drugs-design, synthesis, isolation, physical spectroscopic and mass spectrometric elucidation of novel functionalization derivatives of Cytisine (Cyt), using nucleosidic residues. Since these alkaloids have established biochemical profile, related the binding affinity of the nicotinic acetylcholine receptors (nAChRs), particularly ?7 sub-type, the presented correlation between the molecular structure and properties allowed to evaluated the highlights of the biochemical hypothesises related the Schizophrenia. The anticancer activity of ?7 subtype agonists and the crucial role of the nucleoside-based medications in the cancer therapy provided opportunity for further study on the biochemical relationship between Schizophrenia and few kinds of cancers, which has been hypothesized recently. The physical electronic absorptions (EAs), circular dichroic (CD) and Raman spectroscopic (RS) properties as well as mass spectrometric (MS) data, obtained using electrospray ionization (ESI) and atmospheric-pressure chemical ionization (APCI) methods under the positive single (MS) and tandem (MS/MS) modes of operation are discussed. Taking into account reports on a fatal intoxication of Cyt, the presented data would be of interest in the field of forensic chemistry, through development of highly selective and sensitive analytical protocols. Quantum chemical method is used to predict the physical properties of the isolated alkaloids, their affinity to the receptor loop and gas-phase stabilized species, observed mass spectrometrically.

Ivanova, Bojidarka; Spiteller, Michael

2013-02-01

399

Experimental Studies of the Heat Transfer to RBCC Rocket Nozzles for CFD Application to Design Methodologies  

NASA Technical Reports Server (NTRS)

Rocket thrusters for Rocket Based Combined Cycle (RBCC) engines typically operate with hydrogen/oxygen propellants in a very compact space. Packaging considerations lead to designs with either axisymmetric or two-dimensional throat sections. Nozzles tend to be either two- or three-dimensional. Heat transfer characteristics, particularly in the throat, where the peak heat flux occurs, are not well understood. Heat transfer predictions for these small thrusters have been made with one-dimensional analysis such as the Bartz equation or scaling of test data from much larger thrusters. The current work addresses this issue with an experimental program that examines the heat transfer characteristics of a gaseous oxygen (GO2)/gaseous hydrogen (GH2) two-dimensional compact rocket thruster. The experiments involved measuring the axial wall temperature profile in the nozzle region of a water-cooled gaseous oxygen/gaseous hydrogen rocket thruster at a pressure of 3.45 MPa. The wall temperature measurements in the thruster nozzle in concert with Bartz's correlation are utilized in a one-dimensional model to obtain axial profiles of nozzle wall heat flux.

Santoro, Robert J.; Pal, Sibtosh

1999-01-01

400

Design and experimental studies on ceramic port cover for dual pulse motor  

NASA Astrophysics Data System (ADS)

Material and definition of dome-shaped ceramic port cover contour is presented. Two types of ceramic port covers with equal thickness and variable thickness structures are proposed. A group of cold-flow tests was carried out on a reusable dual pulse motor in which the performances of different port covers including sealing, first-pulse pressure bearing and second-pulse broken pressure were experimentally studied. A solid dual pulse motor for hot-firing test was designed, manufactured and statically tested. The feasibility of proposed bulkhead with ceramic port cover employed on actual solid dual pulse motor was proved. It is found that dome-shaped port cover made from machinable glass ceramic withstands a high pressure on its convex side, but is prone to fragmentation while imposing a reasonably low pressure on its concave side. The peripherally thickened port cover that is more robust in machining and assembly process is recommended. Grooves milled on the port cover induce fragmentation and are helpful to produce regular broken aperture shape. The bulkhead assembly consists of retaining ring, port cover and supporting ring can well fulfill the requirements of port cover in fixing, preloading and sealing. The broken fragments are less likely to damage the insulation structures of the combustion chamber and the nozzle unit which had been validated in the test.

Wang, Chang-Hui; Liu, Yu; Liu, Ya-Bing

2011-06-01

401

Design and development of experimental facilities for short duration, low-gravity combustion and fire experiments  

NASA Technical Reports Server (NTRS)

This report contains the results of three projects conducted by undergraduate students from Worcester Polytechnic Institute at the NASA's Lewis Research Center under a NASA Award NCC3-312. The students involved in these projects spent part of the summer of 1993 at the Lewis Research Center (LeRC) under the direction of Dr. Howard Ross, head of the Combustion group and other NASA engineers and scientists. The Principal Investigator at Worcester Polytechnic Institute was Professor Vahid Motevalli. Professor Motevalli served as the principal project advisor for two of the three projects which were in Mechanical Engineering. The third project was advised by Professor Duckworth of Electrical and Computer Engineering, while Professor Motevalli acted as the co-advisor. These projects provided an excellent opportunity for the students to participate in the cutting edge research and engineering design, interact with NASA engineers and gain valuable exposure to a real working environment. Furthermore, the combustion group at LeRC was able to forward their goals by employing students to work on topics of immediate use and interest such as experimental research projects planned for the space shuttle, the future space station, or to develop demonstration tools to educate the public about LeRC activities.

Motevalli, Vahid

1994-01-01

402

Tree Crown Delineation on Vhr Aerial Imagery with Svm Classification Technique Optimized by Taguchi Method: a Case Study in Zagros Woodlands  

NASA Astrophysics Data System (ADS)

The Support Vector Machine (SVM) is a theoretically superior machine learning methodology with great results in classification of remotely sensed datasets. Determination of optimal parameters applied in SVM is still vague to some scientists. In this research, it is suggested to use the Taguchi method to optimize these parameters. The objective of this study was to detect tree crowns on very high resolution (VHR) aerial imagery in Zagros woodlands by SVM optimized by Taguchi method. A 30 ha plot of Persian oak (Quercus persica) coppice trees was selected in Zagros woodlands, Iran. The VHR aerial imagery of the plot with 0.06 m spatial resolution was obtained from National Geographic Organization (NGO), Iran, to extract the crowns of Persian oak trees in this study. The SVM parameters were optimized by Taguchi method and thereafter, the imagery was classified by the SVM with optimal parameters. The results showed that the Taguchi method is a very useful approach to optimize the combination of parameters of SVM. It was also concluded that the SVM method could detect the tree crowns with a KHAT coefficient of 0.961 which showed a great agreement with the observed samples and overall accuracy of 97.7% that showed the accuracy of the final map. Finally, the authors suggest applying this method to optimize the parameters of classification techniques like SVM.

Erfanifard, Y.; Behnia, N.; Moosavi, V.

2013-09-01

403

Multi-Response Optimization of Process Parameters for Low-Pressure Cold Spray Coating Process Using Taguchi and Utility Concept  

NASA Astrophysics Data System (ADS)

Most of the existing multi-response optimization approaches focus on the subjective and practical know-how of the process. As a result, some confusion and uncertainty are introduced in the overall decision-making process. In this work, an approach based on a Utility theory and Taguchi quality loss function has been applied to the process parameters for low-pressure cold spray process deposition of copper coatings, for simultaneous optimization of more than one response characteristics. In the present paper, two potential response parameters, i.e., coating thickness and coating density, have been selected. Utility values based on these response parameters have been analyzed for optimization using the Taguchi approach. The selected input parameters of powder feeding arrangement, substrate material, air stagnation pressure, air stagnation temperature, and stand-off distance significantly improve the Utility function (raw data) comprising quality characteristics (coating thickness and coating density). The percentage contribution of the parameters to achieve a higher value of Utility function is substrate material (50.03%), stand-off distance (28.87%), air stagnation pressure (6.41%), powder feeding arrangement (4.68%), and air stagnation temperature (2.64%).

Goyal, Tarun; Sidhu, T. S.; Walia, R. S.

2014-01-01

404

Shielding analysis and design of the KIPT experimental neutron source facility of Ukraine.  

SciTech Connect

Argonne National Laboratory (ANL) of USA and Kharkov Institute of Physics and Technology (KIPT) of Ukraine have been collaborating on the conceptual design development of an experimental neutron source facility based on the use of an electron accelerator driven subcritical (ADS) facility [1]. The facility uses the existing electron accelerators of KIPT in Ukraine. The neutron source of the sub-critical assembly is generated from the interaction of 100 KW electron beam with a natural uranium target. The electron beam has a uniform spatial distribution and the electron energy in the range of 100 to 200 MeV, [2]. The main functions of the facility are the production of medical isotopes and the support of the Ukraine nuclear power industry. Reactor physics experiments and material performance characterization will also be carried out. The subcritical assembly is driven by neutrons generated by the electron beam interactions with the target material. A fraction of these neutrons has an energy above 50 MeV generated through the photo nuclear interactions. This neutron fraction is very small and it has an insignificant contribution to the subcritical assembly performance. However, these high energy neutrons are difficult to shield and they can be slowed down only through the inelastic scattering with heavy isotopes. Therefore the shielding design of this facility is more challenging relative to fission reactors. To attenuate these high energy neutrons, heavy metals (tungsten, iron, etc.) should be used. To reduce the construction cost, heavy concrete with 4.8 g/cm{sup 3} density is selected as a shielding material. The iron weight fraction in this concrete is about 0.6. The shape and thickness of the heavy concrete shield are defined to reduce the biological dose equivalent outside the shield to an acceptable level during operation. At the same time, special attention was give to reduce the total shield mass to reduce the construction cost. The shield design is configured to maintain the biological dose equivalent during operation {le} 0.5 mrem/h inside the subcritical hall, which is five times less than the allowable dose for working forty hours per week for 50 weeks per year. This study analyzed and designed the thickness and the shape of the radial and top shields of the neutron source based on the biological dose equivalent requirements inside the subcritical hall during operation. The Monte Carlo code MCNPX is selected because of its capabilities for transporting electrons, photons, and neutrons. Mesh based weight windows variance reduction technique is utilized to estimate the biological dose outside the shield with good statistics. A significant effort dedicated to the accurate prediction of the biological dose equivalent outside the shield boundary as a function of the shield thickness without geometrical approximations or material homogenization. The building wall was designed with ordinary concrete to reduce the biological dose equivalent to the public with a safety factor in the range of 5 to 20.

Zhong, Z.; Gohar, M. Y. A.; Naberezhnev, D.; Duo, J.; Nuclear Engineering Division

2008-10-31

405

Design and operating experience on the US Department of Energy experimental Mod-0 100-kW wind turbine  

NASA Technical Reports Server (NTRS)

The experimental wind turbine was designed and fabricated to assess technology requirements and engineering problems of large wind turbines. The machine has demonstrated successful operation in all of its design modes and served as a prototype developmental test bed for the Mod-0A operational wind turbines which are currently used on utility networks. The mechanical and control system are described as they evolved in operational tests and some of the experience with various systems in the downwind rotor configurations are elaborated.

Glasgow, J. C.; Birchenough, A. G.

1978-01-01

406

The engineering analysis of bioheat equation and penile hemodynamic relationships in the diagnosis of erectile dysfunction: part II-model optimization using the ANOVA and Taguchi method.  

PubMed

The authors aimed to study the skin surface bioheat perfusion model described in part I numerically. The influence of each constituent in the determination of surface temperature profile was statistically examined. The theoretically derived data will then be benchmarked with clinically measured data to develop the artificial intelligence system for the diagnosis of erectile dysfunction (ED). The new approach is based on the hypothesis that there exists a constitutive relationship between surface temperature profiles and the etiology of ED. By considering the penis model as a group of reservoirs with irregular cavities, we built a numerical model, simplified to save computational costs while still realistically able to represent the actual for partial differential calculation. Incompressible blood flow was assumed coupled with the classical bioheat transfer equation which was solved using the finite element method. Isotropic homogeneous heat diffusivity was assigned to each tissue layer. The results of simulations were tested for sensitivity analysis and further optimized to obtain the 'best' signal from the simulations using the Taguchi method. Four important parameters were identified and analysis of variance was performed using the 2(n) design (n=number of parameters, in this case, 4). The implications of these parameters were hypothesized based on physiological observations. Our results show that for an optimum signal-to-noise (S/N) ratio, the noise factors (thermal conductivity of skin, A and tunica albuginea, B) must be set high and low, respectively. Hence, at this setting, the signal will be captured based on the perfusion rate of the boundary layer of the sinusoidal space and the blood pressure (perfusion of sinusoidal space, C and blood pressure, D) will be optimal as their S/N ratios (C (low) and D (low)) are larger than the former. PMID:18075508

Ng, E Y K; Ng, W K; Huang, J; Tan, Y K

2008-01-01

407

Data Processing and Experimental Design for Micrometeorite Impacts in Small Bodies  

NASA Technical Reports Server (NTRS)

Comets and asteroids have been altered from their original "pristine" state by impacts occurring throughout their 4.5 billion year lives: [1]. Proof of shock deformation has been detected in the crystal structure of several Stardust samples from Comet Wild 2 [2, 3]. Analyses indicated that the planar dislocations in the crystal structure of the minerals had been imparted by impacts sustained during their lives, and not due to the aerogel capture process. Distortions to crystal structure also affect the ideal absorption spectra in the infrared, and [4], thus providing indirect evidence of its impact history and a means of remotely investigating the impact history of small bodies through comparing laboratory spectra with spectra observed by telescopes or spacecraft. -The effects of impacts propagating shock waves through minerals were investigated through laboratory impact experiments. Utilizing NASA Johnson Space Center's Experimental Impact Laboratory, projectiles were fired from the vertical gun at velocities ranging from 2.0 to 2.8 km/sec, projected impact velocities between Kuiper Belt Objects. Two types of projectiles were used, including spherical alumina ceramic, whose density mimics that of rock, and cylinders made from the same material that they impacted. The target materials chosen for testing included: OLIVINES forsterite (Mg2SiO4) and fayalite, Fe2SiO4); PYROXENES enstatite (Mg2Si2O6) and diopside (MgCaSi2O6); and CARBONATES magnesite (MgCO3) and siderite (FeCO3). Targets were impacted at either 25 C or cooled to -20 C to examine the effects of temperature, if any, on lattice distortions during the shock propagation. As comets and asteroids can undergo a wide range of temperatures in their orbital lifetimes, the effect of temperature on the equation of state of minerals being shocked needs to be examined for interpreting the results of these experiments. The porosity of the target mineral is varied by either grinding it into a powder/granular texture or as whole mineral rocks to investigate the differences in shock propagation when voids are present. By varying velocity, ambient temperature, and porosity, we can investigate different variables affecting impacts in the solar system. -Data indicates that there is a non-linear relationship between peak shock pressure and the variation in infrared spectral absorbances by the distorted crystal structure. The maximum variability occurs around 37 GPa in enstatite and forsterite. The particle size distribution of the impacted material similarly changes with velocity/peak shock pressure. -The experiments described above are designed to measure the near- to mid-IR effects from these changes to the mineral structure. See Lederer et al., this meeting for additional experimental results.

Jensen, E.; Lederer, S.; Smith, D.; Strojia, C.; Cintala, M.; Zolensky, M.; Keller, L.

2014-01-01

408

The Economist as Engineer: Game Theory, Experimentation, and Computation as Tools for Design Economics  

Microsoft Academic Search

Economists have lately been called upon not only to analyze markets, but to design them. Market design involves a responsibility for detail, a need to deal with all of a market's complications, not just its principle features. Designers therefore cannot work only with the simple conceptual models used for theoretical insights into the general working of markets. Instead, market design

Alvin E. Roth

2002-01-01

409

Microfabricated Air-Microfluidic Sensor for Personal Monitoring of Airborne Particulate Matter: Design, Fabrication, and Experimental Results  

EPA Science Inventory

We present the design and fabrication of a micro electro mechanical systems (MEMS) air-microfluidic particulate matter (PM) sensor, and show experimental results obtained from exposing the sensor to concentrations of tobacco smoke and diesel exhaust, two commonly occurring P...

410

Single-Case Experimental Designs for the Evaluation of Treatments for Self-Injurious and Suicidal Behaviors  

ERIC Educational Resources Information Center

Single-case experimental designs (SCEDs) provide a time- and cost-effective alternative to randomized clinical trials and offer significant advantages in terms of internal and external validity. A brief history and primer on SCEDs is provided, specifically for use in suicide intervention research. Various SCED methodologies, such as AB, ABAB,…

Rizvi, Shireen L.; Nock, Matthew K.

2008-01-01

411

A Simulation Study on the Performance of the Simple Difference and Covariance-Adjusted Scores in Randomized Experimental Designs  

ERIC Educational Resources Information Center

Research by Huck and McLean (1975) demonstrated that the covariance-adjusted score is more powerful than the simple difference score, yet recent reviews indicate researchers are equally likely to use either score type in two-wave randomized experimental designs. A Monte Carlo simulation was conducted to examine the conditions under which the…

Petscher, Yaacov; Schatschneider, Christopher

2011-01-01

412

YYY, Vol. X, No. X, Month 2005, xxxxxx Multi-facilities tactical planning robustness with experimental design  

E-print Network

at proposing an approach based on an experimental design and the use of signal/noise ratio as developed, is developed to solve tactical planning concerns. By adjusting policy parameters, such as overtime, inventory, published in "Production Planning & Control 19, 2 (2008) 171-182" DOI : 10.1080/09537280801896250 #12;P

Boyer, Edmond

413

Third National Even Start Evaluation: Follow-Up Findings from the Experimental Design Study. NCEE 2005-3002  

ERIC Educational Resources Information Center

Citation: Ricciuti, A.E., R.G. St.Pierre, W. Lee, A. Parsad & T. Rimdzius. Third National Even Start Evaluation: Follow-Up Findings From the Experimental Design Study. U.S. Department of Education, Institute of Education Sciences, National Center for Education Evaluation and Regional Assistance. Washington, D.C., 2004. Background: The Even Start…

Ricciuti, Anne E., St.Pierre, Robert G.; Lee, Wang; Parsad, Amanda

2004-01-01

414

Statistical Assistance It is recommended that a statistician be enlisted to assist in developing the experimental design for animal  

E-print Network

the experimental design for animal research projects. Statistical consulting resources at UNL are available from the number of animals needed for each study is required on the Application to Use Animals Form (AUAF of animals should be the minimum number required to obtain statistically valid research results. A power

Farritor, Shane

415

Experimental and computational characterization of designed and fabricated 50:50 PLGA porous scaffolds for human trabecular bone applications  

Microsoft Academic Search

The present study utilizes image-based computational methods and indirect solid freeform fabrication (SFF) technique to design\\u000a and fabricate porous scaffolds, and then computationally estimates their elastic modulus and yield stress with experimental\\u000a validation. 50:50 Poly (lactide-co-glycolide acid) (50:50 PLGA) porous scaffolds were designed using an image-based design technique, fabricated using indirect\\u000a SFF technique, and characterized using micro-computed tomography (?-CT) and

Eiji Saito; Heesuk Kang; Juan M. Taboas; Alisha Diggs; Colleen L. Flanagan; Scott J. Hollister

2010-01-01

416

Experimental design for reflection measurements of highly reactive liquid or solid substances with application to liquid sodium  

SciTech Connect

A versatile goniometer system with associated electronic components and mechanical instruments has been assembled. It is designed to measure spectral, specular reflectances of highly reactive liquid or solid substances over a spectral range of 0.3 to 9 ..mu.. and incidence angles of 12 to 30/sup 0/ off the normal direction. The capability of measuring reflectances of liquid substances clearly distinguishes this experimental design from conventional systems which are applicable only to solid substances. This design has been used to measure the spectral, specular reflectance of liquid sodium and preliminary results obtained are compared with those of solid sodium measured by other investigators.

Chan, S.H.; Gossler, A.A.

1980-06-30

417

Experimental design based on field spectrometry for characterization of fire-affected soils.  

NASA Astrophysics Data System (ADS)

Wildfires can modify physical and chemical properties of soils (Mataix-Solera et al., 2011; Badía et al., 2014). These disturbances involve changes in soil spectral properties, which can be analyzed by using field spectrometry (VIS-SWIR) (Montorio et al., 2008; Guerrero et al., 2010). The aim of this study is to present an experimental design for hyperspectral characterization of fire affected soils in laboratory conditions. We analyzed soil samples from Montes de Zuera area (Aragón, Spain) repeatedly affected by wildfires in the period of 1979-2008. Fourteen samples, seven from the burned zones and the corresponding control samples were collected in spring of 2013. Spectral analysis was performed on subsamples of around 130 g (fine fraction, particle size < 2 mm), previously dried in a stove at 105°C during 36 hours, and placed in crystal petri dishes (90 mm x 15 mm). The spectra were obtained using spectroradiometer ASD FieldSpec® 4 (spectral range from 350 nm to 2500 nm) combined with a Contact Probe ensuring homogeneity of observation and illumination conditions. Spectralon reference panel Labsphere® was used for conversion to reflectance values. The resulting reflectance is an average of the measurements corresponding to five random points of the subsample, each of them representing a mean value of 10 spectra. The averaging of spectra improves the signal to noise ratio and, at the same time, it minimizes the variations caused by the samples surface roughness. Statistically significant differences have been detected between burned and control soils. Reflectance increase of 12% (average for the whole spectrum) was observed in 70% of the samples: 16%, 15% and 10% increase in visible, NIR and SWIR respectively. Therefore regardless of the wildfire date, an increase of reflectance is observed in burned soils due to changes on soil properties. A detailed analysis of physical, chemical and biological properties of soils will be used in further research to explain the higher reflectance of fire-affected soils in the study area.

Rosero, Olga; Vlassova, Lidia; Montorio Llovería, Raquel; Pérez-Cabello, Fernando

2014-05-01

418

Finding a better drug for epilepsy: Preclinical screening strategies and experimental trial design  

PubMed Central

SUMMARY The antiepileptic drugs (AEDs) introduced during the past two decades have provided several benefits: they offered new treatment options for symptomatic treatment of seizures, improved ease of use and tolerability, and lowered risk for hypersensitivity reactions and detrimental drug– drug interactions. These drugs, however, neither attenuated the problem of drug-refractory epilepsy nor proved capable of preventing or curing the disease. Therefore, new preclinical screening strategies are needed to identify AEDs that target these unmet medical needs. New therapies may derive from novel targets identified on the basis of existing hypotheses for drug-refractory epilepsy and the biology of epileptogenesis; from research on genetics, transcriptomics, and epigenetics; and from mechanisms relevant for other therapy areas. Novel targets should be explored using new preclinical screening strategies, and new technologies should be used to develop medium- to high-throughput screening models. In vivo testing of novel drugs should be performed in models mimicking relevant aspects of drug refractory epilepsy and/or epileptogenesis. To minimize the high attrition rate associated with drug development, which arises mainly from a failure to demonstrate sufficient clinical efficacy of new treatments, it is important to define integrated strategies for preclinical screening and experimental trial design. An important tool will be the discovery and implementation of relevant biomarkers that will facilitate a continuum of proof-of-concept approaches during early clinical testing to rapidly confirm or reject preclinical findings, and thereby lower the risk of the overall development effort. In this review, we overview some of the issues related to these topics and provide examples of new approaches that we hope will be more successful than those used in the past. PMID:22708847

Simonato, Michele; Löscher, Wolfgang; Cole, Andrew J.; Dudek, F. Edward; Engel, Jerome; Kaminski, Rafal M.; Loeb, Jeffrey A.; Scharfman, Helen; Staley, Kevin J.; Velíšek, Libor; Klitgaard, Henrik

2014-01-01

419

Elements of designing for cost  

NASA Technical Reports Server (NTRS)

During recent history in the United States, government systems development has been performance driven. As a result, systems within a class have experienced exponentially increasing cost over time in fixed year dollars. Moreover, little emphasis has been placed on reducing cost. This paper defines designing for cost and presents several tools which, if used in the engineering process, offer the promise of reducing cost. Although other potential tools exist for designing for cost, this paper focuses on rules of thumb, quality function deployment, Taguchi methods, concurrent engineering, and activity-based costing. Each of these tools has been demonstrated to reduce cost if used within the engineering process.

Dean, Edwin B.; Unal, Resit

1992-01-01

420

Elements of Designing for Cost  

NASA Technical Reports Server (NTRS)

During recent history in the United States, government systems development has been performance driven. As a result, systems within a class have experienced exponentially increasing cost over time in fixed year dollars. Moreover, little emphasis has been placed on reducing cost. This paper defines designing for cost and presents several tools which, if used in the engineering process, offer the promise of reducing cost. Although other potential tools exist for designing for cost, this paper focuses on rules of thumb, quality function deployment, Taguchi methods, concurrent engineering, and activity based costing. Each of these tools has been demonstrated to reduce cost if used within the engineering process.

Dean, Edwin B.; Unal, Resit

1992-01-01

421

Experimental design for reflection measurements of highly reactive liquid or solid substances with application to liquid sodium. [LMFBR  

SciTech Connect

This technical report describes the experimental part of a program on thermal radiation properties of reactor materials. A versatile goniometer system with associated electronic components and mechanical instruments has been assembled. It is designed to measure spectral, specular reflectances of highly reactive liquid or solid substances over a spectral range of 0.3 ..mu.. to 9 ..mu.. and incidence angles of 12/sup 0/ to 30/sup 0/ off the normal direction. The capability of measuring reflectances of liquid substances clearly distinguishes this experimental design from conventional systems which are applicable only to solid substances. This design has been used to measure the spectral, specular reflectance of liquid sodium and preliminary results obtained are compared with those of solid sodium measured by other investigators.

Chan, S.H.; Gossler, A.A.

1980-06-30

422

Quality Appraisal of Single-Subject Experimental Designs: An Overview and Comparison of Different Appraisal Tools  

ERIC Educational Resources Information Center

Critical appraisal of the research literature is an essential step in informing and implementing evidence-based practice. Quality appraisal tools that assess the methodological quality of experimental studies provide a means to identify the most rigorous research suitable for evidence-based decision-making. In single-subject experimental research,…

Wendt, Oliver; Miller, Bridget

2012-01-01

423

THE ECONOMIST AS ENGINEER: GAME THEORY, EXPERIMENTATION, AND COMPUTATION AS TOOLS FOR DESIGN ECONOMICS1  

Microsoft Academic Search

Economists have lately been called upon not only to analyze markets, but to design them. Market design involves a responsibility for detail, a need to deal with all of a mar- ket's complications, not just its principle features. Designers therefore cannot work only with the simple conceptual models used for theoretical insights into the general working of markets. Instead, market

Alvin E. Roth

424

Quiet, Clean, Short-Haul Experimental Engine (QCSEE) Over-The-Wing (OTW) engine acoustic design  

NASA Technical Reports Server (NTRS)

The acoustic considerations involved in the low source noise basic engine design and the design procedures followed in the development of the over-the-wing (OTW) nacelle acoustic treatment design are presented. Laboratory experiments, component tests, and scale model and engine tests supporting the OTW engine acoustic design are referenced. Acoustic design features include a near-sonic inlet, low fan and core pressure ratios, low fan tip speed, high and low frequency stacked core treatment, multiple thickness treatment, and fan frame and stator vane treatment.

Sowers, H. D.; Coward, W. E.

1978-01-01

425

Tribological behaviour and statistical experimental design of sintered iron-copper based composites  

NASA Astrophysics Data System (ADS)

The sintered iron-copper based composites for automotive brake pads have a complex composite composition and should have good physical, mechanical and tribological characteristics. In this paper, we obtained frictional composites by Powder Metallurgy (P/M) technique and we have characterized them by microstructural and tribological point of view. The morphology of raw powders was determined by SEM and the surfaces of obtained sintered friction materials were analyzed by ESEM, EDS elemental and compo-images analyses. One lot of samples were tested on a "pin-on-disc" type wear machine under dry sliding conditions, at applied load between 3.5 and 11.5 × 10-1 MPa and 12.5 and 16.9 m/s relative speed in braking point at constant temperature. The other lot of samples were tested on an inertial test stand according to a methodology simulating the real conditions of dry friction, at a contact pressure of 2.5-3 MPa, at 300-1200 rpm. The most important characteristics required for sintered friction materials are high and stable friction coefficient during breaking and also, for high durability in service, must have: low wear, high corrosion resistance, high thermal conductivity, mechanical resistance and thermal stability at elevated temperature. Because of the tribological characteristics importance (wear rate and friction coefficient) of sintered iron-copper based composites, we predicted the tribological behaviour through statistical analysis. For the first lot of samples, the response variables Yi (represented by the wear rate and friction coefficient) have been correlated with x1 and x2 (the code value of applied load and relative speed in braking points, respectively) using a linear factorial design approach. We obtained brake friction materials with improved wear resistance characteristics and high and stable friction coefficients. It has been shown, through experimental data and obtained linear regression equations, that the sintered composites wear rate increases with increasing applied load and relative speed, but in the same conditions, the frictional coefficients slowly decrease.

Popescu, Ileana Nicoleta; Ghi??, Constantin; Bratu, Vasile; Palacios Navarro, Guillermo

2013-11-01

426

Design and wind tunnel experimentation of a variable blade drag type vertical axis wind turbine  

NASA Astrophysics Data System (ADS)

The primary purpose of this research effort is to propose a novel efficiency boosting design feature in a drag type vertical axis wind turbine (VAWT), explore practicality through design and fabrication, and test the viability of the design through wind tunnel experiments. Using adaptive control surface design and an improved blade shape can be very useful in harnessing the wind's energy in low wind speed areas. The new design is based on a series of smaller blade elements to make any shape, which changes to reduce a negative resistance as it rotates and thus maximizing the useful torque. As such, these blades were designed into a modified Savonius wind turbine with the goal of improving upon the power coefficient produced by a more conventional design. The experiment yielded some positive observations with regard to starting characteristics. Torque and angular velocity data was recorded for both the conventional configuration and the newly built configuration and the torque and power coefficient results were compared.

Mays, Samuel; Bahr, Behnam

2012-04-01

427

Experimental Design for Evaluation of Co-extruded Refractory Metal/Nickel Base Superalloy Joints  

SciTech Connect

Prior to the restructuring of the Prometheus Program, the NRPCT was tasked with delivering a nuclear space reactor. Potential NRPCT nuclear space reactor designs for the Prometheus Project required dissimilar materials to be in contact with each other while operating at extreme temperatures under irradiation. As a result of the high reactor core temperatures, refractory metals were the primary candidates for many of the reactor structural and cladding components. They included the tantalum-base alloys ASTAR-811C and Ta-10W, the niobium-base alloy FS-85, and the molybdenum base alloys Moly 41-47.5 Rhenium. The refractory metals were to be joined to candidate nickel base alloys such as Haynes 230, Alloy 617, or Nimonic PE 16 either within the core if the nickel-base alloys were ultimately selected to form the outer core barrel, or at a location exterior to the core if the nickel-base alloys were limited to components exterior to the core. To support the need for dissimilar metal joints in the Prometheus Project, a co-extrusion experiment was proposed. There are several potential methods for the formation of dissimilar metal joints, including explosive bonding, friction stir welding, plasma spray, inertia welding, HIP, and co-extrusion. Most of these joining methods are not viable options because they result in the immediate formation of brittle intermetallics. Upon cooling, intermetallics form in the weld fusion zone between the joined metals. Because brittle intermetallics do not form during the initial bonding process associated with HIP, co-extrusion, and explosive bonding, these three joining procedures are preferred for forming dissimilar metal joints. In reference to a Westinghouse Astronuclear Laboratory report done under a NASA sponsored program, joints that were fabricated between similar materials via explosive bonding had strengths that were directly affected by the width of the diffusion barrier. It was determined that the diffusion zone should not exceed a critical thickness (0.0005 in.). A diffusion barrier that exceeded this thickness would likely fail. The joint fabrication method must therefore mechanically bond the two materials causing little or no interdiffusion upon formation. Co-extrusion fits this description since it forms a mechanical joint between two materials by using heat and pressure. The two materials to be extruded are first assembled and sealed within a co-extrusion billet which is subsequently heated and then extruded through a die. For a production application, once the joint is formed, it is dejacketed to remove the outer canister. The remaining piece consists of two materials bonded together with a thin diffusion barrier. Therefore, the long-term stability of the joint is determined primarily by the kinetics of interdiffusion reaction between the two materials. An experimental design for co-extrusion of refractory metals and nickel-based superalloys was developed to evaluate this joining process and determine the long-term stability of the joints.

ME Petrichek

2005-12-16

428

The application of statistically designed experiments to resistance spot welding  

NASA Technical Reports Server (NTRS)

State-of-the-art Resistance Spot Welding (RSW) equipment has the potential to permit realtime monitoring of operations through advances in computerized process control. In order to realize adaptive feedback capabilities, it is necessary to establish correlations among process variables, welder outputs, and weldment properties. The initial step toward achieving this goal must involve assessment of the effect of specific process inputs and the interactions among these variables on spot weld characteristics. This investigation evaluated these effects through the application of a statistically designed experiment to the RSW process. A half-factorial, Taguchi L sub 16 design was used to understand and refine a RSW schedule developed for welding dissimilar aluminum-lithium alloys of different thickness. The baseline schedule had been established previously by traditional trial and error methods based on engineering judgment and one-factor-at-a-time studies. A hierarchy of inputs with respect to each other was established, and the significance of these inputs with respect to experimental noise was determined. Useful insight was gained into the effect of interactions among process variables, particularly with respect to weldment defects. The effects of equipment related changes associated with disassembly and recalibration were also identified. In spite of an apparent decrease in equipment performance, a significant improvement in the maximum strength for defect-free welds compared to the baseline schedule was achieved.

Hafley, Robert A.; Hales, Stephen J.

1991-01-01

429

The Geometric Design of Spherical Mechanical Linkages with Differential Task Specifications: Experimental Set Up and Applications  

E-print Network

The thesis focuses on the development of an experimental set up for a recently developed failure recovery technique of spatial robot manipulators. Assuming a general configuration of the spatial robot arm, a task is specified. This task contains...

Kapila Bala, Phani Neehar

2012-10-19

430

Quiet Clean Short-haul Experimental Engine (QCSEE) UTW fan preliminary design  

NASA Technical Reports Server (NTRS)

High bypass geared turbofan engines and propulsion systems designed for short-haul passenger aircraft are described. The propulsion technology required for future externally blown flap aircraft with engines located both under the wing and over the wing is emphasized. The aerodynamic and mechanical preliminary design of the QCSEE under the wing 1.34 pressure ratio fan with variable blade pitch is presented. Design information is given for two pitch change actuation systems which will provide reverse thrust.

1975-01-01

431

New formulation of minimum-bias central composite experimental design and Gauss quadrature  

Microsoft Academic Search

Response surface methods provide a powerful tool for constructing approximations to complex response functions. Statistical design of experiments is usually used to select optimal points that minimize the error in the resulting response surface approximation. Traditionally, data points are selected using minimum-variance designs, for example the D-optimal design, which may result in large bias errors for low-order approximation. Minimum-bias criteria

X. Qu; G. Venter; R. T. Haftka

2004-01-01

432

[Oxidation of sulfur-containing substrates by aboriginal and experimentally designed microbial communities].  

PubMed

Aboriginal and experimental (constructed of pure microbial cultures) communities of acidophilic chemolithotrophs have been studied. The oxidation of elemental sulfur, sodium thiosulfate, and potassium tetrathionate as sole sources of energy has been monitored. The oxidation rate of the experimental community is higher as compared to the aboriginal community isolated from a flotation concentrate of pyrrhotine-containing pyrite-arsenopyrite gold-arsenic sulfide ore. The degree of oxidation of the mentioned S substrates amounts to 17.91, 68.30, and 93.94% for the experimental microbial community and to 10.71, 56.03, and 79.50% for the aboriginal community, respectively. The degree of oxidation of sulfur sulfide forms in the ore flotation concentrate is 59.15% by the aboriginal microbial community and 49.40% by the experimental microbial community. Despite a higher rate of oxidation of S substrates as a sole source of energy by the experimental microbial community, the aboriginal community oxidizes S substrates at a higher rate in the flotation concentrate of pyrrhotine-containing pyrite-arsenopyrite gold-arsenic sulfide ore, from which it was isolated. Bacterial-chemical oxidation of the flotation concentrate by the aboriginal microbial community allows for the extraction of an additional 32.3% of gold from sulfide minerals, which is by 5.7% larger compared to the yield obtained by the experimental microbial community. PMID:23330391

Pivovarova, T A; Bulaev, A G; Roshchupko, P V; Bely?, A V; Kondrat'eva, T F

2012-01-01

433

Design and Status of the Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII): An Interferometer at the Edge of Space  

NASA Technical Reports Server (NTRS)

The Balloon Experimental Twin Telescope for Infrared Interferometry (BETTII) is an 8-meter baseline far-infraredinterferometer designed to fly on a high altitude balloon. BETTII uses a double-Fourier Michelson interferometer tosimultaneously obtain spatial and spectral information on science targets; the long baseline permits subarcsecond angular resolution, a capability unmatched by other far-infrared facilities. Here, we present key aspects of the overall design of the mission and provide an overview of the current status of the project. We also discuss briefly the implications of this experiment for future space-based far-infrared interferometers.

Rinehart, Stephen A.; Barclay, Richard B.; Barry, R. K.; Benford, D. J.; Calhoun, P. C.; Fixsen, D. J.; Gorman, E. T.; Jackson, M. L.; Jhabvala, C. A.; Leisawitz, D. T.; Maher, S. F.; Mentzell, J. E.; Mundy, L. G.; Rizzo, M. J.; Silverberg, R. F.; Staguhn, J. G.

2012-01-01

434

Optimization of an Optical Inspection System Based on the Taguchi Method for Quantitative Analysis of Point-of-Care Testing  

PubMed Central

This study presents an optical inspection system for detecting a commercial point-of-care testing product and a new detection model covering from qualitative to quantitative analysis. Human chorionic gonadotropin (hCG) strips (cut-off value of the hCG commercial product is 25 mIU/mL) were the detection target in our study. We used a complementary metal-oxide semiconductor (CMOS) sensor to detect the colors of the test line and control line in the specific strips and to reduce the observation errors by the naked eye. To achieve better linearity between the grayscale and the concentration, and to decrease the standard deviation (increase the signal to noise ratio, S/N), the Taguchi method was used to find the optimal parameters for the optical inspection system. The pregnancy test used the principles of the lateral flow immunoassay, and the colors of the test and control line were caused by the gold nanoparticles. Because of the sandwich immunoassay model, the color of the gold nanoparticles in the test line was darkened by increasing the hCG concentration. As the results reveal, the S/N increased from 43.48 dB to 53.38 dB, and the hCG concentration detection increased from 6.25 to 50 mIU/mL with a standard deviation of less than 10%. With the optimal parameters to decrease the detection limit and to increase the linearity determined by the Taguchi method, the optical inspection system can be applied to various commercial rapid tests for the detection of ketamine, troponin I, and fatty acid binding protein (FABP). PMID:25256108

Yeh, Chia-Hsien; Zhao, Zi-Qi; Shen, Pi-Lan; Lin, Yu-Cheng

2014-01-01

435

Optimization of Injection-Molding Process of Short Glass Fiber and Polytetrafluoroethylene Reinforced Polycarbonate Composites via Design of Experiments Method: A Case Study  

Microsoft Academic Search

This study analyses the tribological behaviors and mechanical properties of polycarbonate (PC) reinforced with 20% short glass fiber (SGF) and 6% polytetrafluoroethylene (PTFE), which is applied to the bottom cover of the card reader body. In order to reduce the number of experiments, the design of experiments (DOE) method based on Taguchi's orthogonal arrays were applied. The specimens were prepared

Yung-Kuang Yang

2006-01-01

436

Preliminary assessment of existing experimental data for validation ofreactor physics codes and data for NGNP design and analysis.  

SciTech Connect

The Next Generation Nuclear Plant (NGNP), a demonstration reactor and hydrogen production facility proposed for construction at the INEEL, is expected to be a high-temperature gas-cooled reactor (HTGR). Computer codes used in design and safety analysis for the NGNP must be benchmarked against experimental data. The INEEL and ANL have examined information about several past and present experimental and prototypical facilities based on HTGR concepts to assess the potential of these facilities for use in this benchmarking effort. Both reactors and critical facilities applicable to pebble-bed and prismatic block-type cores have been considered. Four facilities--HTR-PROTEUS, HTR-10, ASTRA, and AVR--appear to have the greatest potential for use in benchmarking codes for pebble-bed reactors. Similarly, for the prismatic block-type reactor design, two experiments have been ranked as having the highest priority--HTTR and VHTRC.

Terry, W. K.; Jewell, J. K.; Briggs, J. B.; Taiwo, T. A.; Park, W.S.; Khalil, H. S.

2005-10-25

437

Application of mixture experimental design in the formulation and optimization of matrix tablets containing carbomer and hydroxy-propylmethylcellulose.  

PubMed

Using mixture experimental design, the effect of carbomer (Carbopol((R)) 971P NF) and hydroxypropylmethylcellulose (Methocel((R)) K100M or Methocel((R)) K4M) combination on the release profile and on the mechanism of drug liberation from matrix tablet was investigated. The numerical optimization procedure was also applied to establish and obtain formulation with desired drug release. The amount of TP released, release rate and mechanism varied with carbomer ratio in total matrix and HPMC viscosity. Increasing carbomer fractions led to a decrease in drug release. Anomalous diffusion was found in all matrices containing carbomer, while Case - II transport was predominant for tablet based on HPMC only. The predicted and obtained profiles for optimized formulations showed similarity. Those results indicate that Simplex Lattice Mixture experimental design and numerical optimization procedure can be applied during development to obtain sustained release matrix formulation with desired release profile. PMID:20162406

Petrovic, Aleksandra; Cvetkovic, Nebojsa; Ibric, Svetlana; Trajkovic, Svetlana; Djuric, Zorica; Popadic, Dragica; Popovic, Radmila

2009-12-01

438

The effect of process conditions on the alpha-amylolytic hydrolysis of amylopectin potato starch: An experimental design approach.  

PubMed

The hydrolysis of amylopectin potato starch with Bacillus licheniformis alpha-amylase (Maxamyl) was studied under industrially relevant conditions (i.e. high dry-weight concentrations). The following ranges of process conditions were chosen and investigated by means of an experimental design: pH [5.6-7.6]; calcium addition [0-120 microg/g]; temperature [63-97 degrees C]; dry-weight concentration [3-37% [w/w

Marchal, L M; Jonkers, J; Franke, G T; de Gooijer, C D; Tramper, J

1999-02-01

439

Central composite experimental design in the optimization of lignin peroxidase production in shake cultures by free and immobilized Phanerochaete chrysosporium  

Microsoft Academic Search

An orthogonal 23-factorial experimental design was employed in the multivariate optimization of lignin peroxidase production by Phanerochaete chrysosporium in shake cultures both as free pellets and as immobilized on nylon-web, and to provide knowledge on the process for scale-up and control. It was observed that a short starving period after the growth of the mycelium and the depletion of the

S. Linko; L.-C. Zhong

1990-01-01

440

Genetic Algorithms Can Improve the Construction of D-Optimal Experimental Designs  

E-print Network

algorithms for constructing D- optimal designs are Monte Carlo algorithms, heuristics, that base on the idea that are D-optimal. To this purpose, we use standard Monte Carlo algorithms such as DETMAX and k better results. Key-Words: - Genetic Algorithm, Memetic Algorithm, Design of Experiments, DOE, D

Zell, Andreas

441

Experimental Analysis for TDMA MAC Design\\/Implementation of the IEEE 802.16 SS  

Microsoft Academic Search

This paper presents the analysis of TDMA MAC applied to the IEEE 802.16 subscriber station and the uplink timin