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Different Designs (different + design)
Selected AbstractsTHE INFLUENCE of FIELD STRENGTH, SUGAR and SOLID CONTENT ON ELECTRICAL CONDUCTIVITY of STRAWBERRY PRODUCTSJOURNAL OF FOOD PROCESS ENGINEERING, Issue 1 2003I. CASTRO ABSTRACT The effects of field strength, soluble solids (from 14 to 59.5 °Brix) and particle size (using two size distributions) on electrical conductivity were investigated. Electrical conductivity increased with temperature for all the products and conditions tested following linear or quadratic relations. Electrical conductivity was found to vary greatly between strawberry-based products. an increase of electrical conductivity with field strength was obvious for fresh strawberries and strawberry jelly but not for strawberry pulp, probably due to the presence of texturizing agents. This parameter decreases with the increase of solids and sugar content. For some of the formulations tested (solid content over 20% w/w and over 40 °Brix) a different design of ohmic heater may be necessary because of the low values of electrical conductivity. [source] In vivo horizontal forces on implants depending on the type of occlusionJOURNAL OF ORAL REHABILITATION, Issue 9 2002T. MORNEBURG Minimizing horizontal forces on implants is one of the important aims of an occlusal design. Therefore, several proposals have been made in literature, e.g. flat cuspal slopes or narrow occlusal surfaces. Our aim was to test how these occlusal designs would influence horizontal forces. Ten healthy subjects with unilateral partially edentulous arches were provided with fixed partial dentures (FPD) on two ITI-implants. The opposing jaw was fully dentate. After an adaptation of 6 month measurement setups with a measuring FPD were put into the mouth. The sensoring device, which consisted of two abutments equipped with strain gauges, evaluated the forces in three dimensions. For each person three FPDs were made with a different design of the occlusal surface. The first FPD exhibited cusps with steep slopes (S), the second showed flat cusps (F) and the third had a narrow occlusal surface (N). The peak forces of the chewing cycles of each patient were evaluated. While chewing wine gum the average values of the vertical forces of the three different FPDs showed no significant differences and amounted to between 253·8 N (s.d. 85·7 N) and 273·9 N (s.d. 63·7 N). With the first FPD (S) mean horizontal forces of 47·9 N (s.d. 34·8 N) were found whereas with the flat surface an average force of 47·4 N (s.d. 37·1 N) was measured. The narrow occlusal surface was associated with an average reduction of the horizontal forces of about 50·9% to a mean value of 24·4 N (s.d. 10·6 N) (P < 0·005). The inclination of occlusal slopes did neither affect vertical nor horizontal forces significantly. However, narrowing of the occlusal surface in the oro-vestibular direction by 30% showed a significant reduction of the lateral forces exerted on the implants by more than 50%. A reduced oro-vestibular width of the occlusal surface is recommended especially for diameter-reduced implants, in case of an unfavourable relationship between implant and crown length or for implants that are strongly inclined to the occlusal plane. [source] Palatal plate of different designs for the suppression of masseter muscle activity during sleep.JOURNAL OF ORAL REHABILITATION, Issue 9 2002A challenge to the concept of placebo splint Several designs of palatal appliance have been reported for the treatment of craniomandibular disorders. However, the effect of these appliances has not yet been fully clarified. This study aimed to reveal the effect of palatal appliances of different design on masseter muscle activity during sleep. Four volunteers (three women and one man, mean age 36·0 years) were used in this study. For each subject, four different types of palatal appliances were used. The palatal appliances were (1) horse shoe type (1 mm thick), (2) thin appliance which covered the whole palate (1 mm thick), (3) thick appliance which filled the palatal concavity and (4) appliance with half the thickness of the third appliance. These appliances were worn for 1 week in a randomized sequence with 1-week interval between each appliance. Right masseter muscle EMG was recorded three nights per week at home. The EMG signal longer than 0·25 s was classified as a burst and a signal shorter than 0·25 s was classified as a brief burst of fragmentary myoclonus (FM). Mean number of burst per hour for four subjects were 7·99 ± 7·32, 3·52 ± 1·95, 5·90 ± 3·99, 2·87 ± 2·87 and 9·96 ± 6·02 for base line, appliance 1, 2, 3 and 4, respectively. Mean number of FM per hour were 136·86 ± 69·88, 90·53 ± 41·19, 99·49 ± 39·29, 71·66 ± 24·66 and 144·39 ± 42·97, respectively. From these results, it was suggested that the thick palatal appliance suppressed the masseter muscle activity during sleep most effectively. Also, the results for appliance 4 questioned the concept of placebo effect for non-occlusal appliances. [source] 3D Image Segmentation of Aggregates from Laser ProfilingCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 4 2003Hyoungkwan Kim Automated scanners of different designs use cameras or lasers to obtain digital images of groups of aggregate particles. To accurately determine particle size and shape parameters, each particle region in the image must be isolated and processed individually. Here, a method for segmenting a particle image acquired from laser profiling is developed using a Canny edge detector and a watershed transformation. Canny edges with rigorous and liberal threshold values are used to outline particle boundaries on a binary image and to check the validity of watersheds, respectively. To find appropriate regional minima in the watershed transformation, a varying search window method is used, where the number of neighboring pixels being compared with the pixel of interest is determined from the height value of the pixel. Test results with this method are promising. When implemented in automated systems that are designed to rapidly assess size and shape characteristics of stone particles, this technique can not only reduce the amount of time required for aggregate preparation, but also increase the accuracy of analysis results. [source] Study on effects of damping in laminated rubber bearings on seismic responses for a , scale isolated test structureEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 10 2002Bong Yoo Abstract The effects of damping in various laminated rubber bearings (LRB) on the seismic response of a ,-scale isolated test structure are investigated by shaking table tests and seismic response analyses. A series of shaking table tests of the structure were performed for a fixed base design and for a base isolation design. Two different types of LRB were used: natural rubber bearings (NRB) and lead rubber bearings (LLRB). Three different designs for the LLRB were tested; each design had a different diameter of lead plug, and thus, different damping values. Artificial time histories of peak ground acceleration 0.4g were used in both the tests and the analyses. In both shaking table tests and analyses, as expected, the acceleration responses of the seismically isolated test structure were considerably reduced. However, the shear displacement at the isolators was increased. To reduce the shear displacement in the isolators, the diameter of the lead plug in the LLRB had to be enlarged to increase isolator damping by more than 24%. This caused the isolator stiffness to increase, and resulted in amplifying the floor acceleration response spectra of the isolated test structure in the higher frequency ranges with a monotonic reduction of isolator shear displacement. Copyright © 2002 John Wiley & Sons, Ltd. [source] On the estimation of species richness based on the accumulation of previously unrecorded speciesECOGRAPHY, Issue 1 2002Emmanuelle Cam Estimation of species richness of local communities has become an important topic in community ecology and monitoring. Investigators can seldom enumerate all the species present in the area of interest during sampling sessions. If the location of interest is sampled repeatedly within a short time period, the number of new species recorded is typically largest in the initial sample and decreases as sampling proceeds, but new species may be detected if sampling sessions are added. The question is how to estimate the total number of species. The data collected by sampling the area of interest repeatedly can be used to build species accumulation curves: the cumulative number of species recorded as a function of the number of sampling sessions (which we refer to as "species accumulation data"). A classic approach used to compute total species richness is to fit curves to the data on species accumulation with sampling effort. This approach does not rest on direct estimation of the probability of detecting species during sampling sessions and has no underlying basis regarding the sampling process that gave rise to the data. Here we recommend a probabilistic, nonparametric estimator for species richness for use with species accumulation data. We use estimators of population size that were developed for capture-recapture data, but that can be used to estimate the size of species assemblages using species accumulation data. Models of detection probability account for the underlying sampling process. They permit variation in detection probability among species. We illustrate this approach using data from the North American Breeding Bird Survey (BBS). We describe other situations where species accumulation data are collected under different designs (e.g., over longer periods of time, or over spatial replicates) and that lend themselves to of use capture-recapture models for estimating the size of the community of interest. We discuss the assumptions and interpretations corresponding to each situation. [source] Enhancement of electrokinetically driven microfluidic T-mixer using frequency modulated electric field and channel geometry effectsELECTROPHORESIS, Issue 18 2009Deguang Yan Abstract This study reports improved electrokinetically driven microfluidic T-mixers to enhance their mixing efficiency. Enhancement of electrokinetic microfluidic T-mixers is achieved using (i) an active approach of utilizing a pulsating EOF, and (ii) a passive approach of using the channel geometry effect with patterned blocks. PDMS-based electrokinetic T-mixers of different designs were fabricated. Experimental measurements were carried out using Rhodamine B to examine the mixing performance and the micro-particle image velocimetry technique to characterize the electrokinetic flow velocity field. Scaling analysis provides an effective frequency range of applied AC electric field. Results show that for a T-mixer of 10,mm mixing length, utilizing frequency modulated electric field and channel geometry effects can increase the mixing efficiency from 50 to 90%. In addition, numerical simulations were performed to analyze the mixing process in the electrokinetic T-mixers with various designs. The simulation results were compared with the experimental data, and reasonable agreement was found. [source] The Role of Leader Morality in the Interaction Effect of Procedural Justice and Outcome FavorabilityJOURNAL OF APPLIED SOCIAL PSYCHOLOGY, Issue 7 2009Xiao-Wan Lin The present research explored the role of leader morality in the interaction effect of procedural justice and outcome favorability, and attempted to connect justice and morality construct in a new direction. Two studies in different settings and using different designs (a scenario experiment and a survey) yielded convergent results. When leader morality was high, the interaction effect of procedural justice and outcome favorability was significant, and fair procedures mitigated the negative effect of low outcome favorability. When leader morality was low, however, the interaction between procedural justice and outcome favorability was absent. [source] Controlling coverage of D-optimal onion designs and selectionsJOURNAL OF CHEMOMETRICS, Issue 12 2004Ing-Marie Olsson Abstract Statistical molecular design (SMD) is a powerful approach for selection of compound sets in medicinal chemistry and quantitative structure,activity relationships (QSARs) as well as other areas. Two techniques often used in SMD are space-filling and D-optimal designs. Both on occasions lead to unwanted redundancy and replication. To remedy such shortcomings, a generalization of D-optimal selection was recently developed. This new method divides the compound candidate set into a number of subsets (,layers' or ,shells'), and a D-optimal selection is made from each layer. This improves the possibility to select representative molecular structures throughout any property space independently of requested sample size. This is important in complex situations where any given model is unlikely to be valid over the whole investigated domain of experimental conditions. The number of selected molecules can be controlled by varying the number of subsets or by altering the complexity of the model equation in each layer and/or the dependency of previous layers. The new method, called D-optimal onion design (DOOD), will allow the user to choose the model equation complexity independently of sample size while still avoiding unwarranted redundancy. The focus of the present work is algorithmic improvements of DOOD in comparison with classical D-optimal design. As illustrations, extended DOODs have been generated for two applications by in-house programming, including some modifications of the D-optimal algorithm. The performances of the investigated approaches are expected to differ depending on the number of principal properties of the compounds in the design, sample sizes and the investigated model, i.e. the aim of the design. QSAR models have been generated from the selected compound sets, and root mean squared error of prediction (RMSEP) values have been used as measures of performance of the different designs. Copyright © 2005 John Wiley & Sons, Ltd. [source] Palatal plate of different designs for the suppression of masseter muscle activity during sleep.JOURNAL OF ORAL REHABILITATION, Issue 9 2002A challenge to the concept of placebo splint Several designs of palatal appliance have been reported for the treatment of craniomandibular disorders. However, the effect of these appliances has not yet been fully clarified. This study aimed to reveal the effect of palatal appliances of different design on masseter muscle activity during sleep. Four volunteers (three women and one man, mean age 36·0 years) were used in this study. For each subject, four different types of palatal appliances were used. The palatal appliances were (1) horse shoe type (1 mm thick), (2) thin appliance which covered the whole palate (1 mm thick), (3) thick appliance which filled the palatal concavity and (4) appliance with half the thickness of the third appliance. These appliances were worn for 1 week in a randomized sequence with 1-week interval between each appliance. Right masseter muscle EMG was recorded three nights per week at home. The EMG signal longer than 0·25 s was classified as a burst and a signal shorter than 0·25 s was classified as a brief burst of fragmentary myoclonus (FM). Mean number of burst per hour for four subjects were 7·99 ± 7·32, 3·52 ± 1·95, 5·90 ± 3·99, 2·87 ± 2·87 and 9·96 ± 6·02 for base line, appliance 1, 2, 3 and 4, respectively. Mean number of FM per hour were 136·86 ± 69·88, 90·53 ± 41·19, 99·49 ± 39·29, 71·66 ± 24·66 and 144·39 ± 42·97, respectively. From these results, it was suggested that the thick palatal appliance suppressed the masseter muscle activity during sleep most effectively. Also, the results for appliance 4 questioned the concept of placebo effect for non-occlusal appliances. [source] Stress distribution associated with loaded ceramic onlay restorations with different designs of marginal preparation.JOURNAL OF ORAL REHABILITATION, Issue 4 2000An FEA study The design of marginal finish of an inlay or onlay could influence the prognosis of the restoration since this area is subjected to various mechanical or chemical actions during function. This study was carried out to determine the tensile stresses which develop at the marginal area when subjected to vertical and horizontal loads. Onlay restorations with three different types of marginal finish, i.e. shoulder, chamfer and bevel, were modelled in three dimensions using the finite element method, and were then subjected to vertical and horizontal load at three different sites. The results show that horizontal forces acting on the restoration generate the highest tensile stresses whilst the vertical forces generate high tensile stresses at the margins of the chamfer and bevel designs. [source] Pressure generated on a simulated oral analog by impression materials in custom trays of different designsJOURNAL OF PROSTHODONTICS, Issue 3 2002Radi Masri BDS Purpose To measure the pressure exerted by maxillary edentulous impressions composed of 3 commonly used impression materials using four different impression tray configurations. Materials and Methods The study was performed using an oral analog that simulated an edentulous maxillary arch. Three pressure transducers were imbedded in the oral analog, 1 in the mid-palate area and the other 2 in the right and left ridge (maxillary first premolar areas). Custom trays of 4 different configurations were fabricated. The 3 impression materials tested were irreversible hydrocolloid, light-body and medium-body vinyl polysiloxane, and polysulfide. A total of 128 impressions were made. The custom tray and the oral analog were mounted using a reline jig. A Satec universal testing machine was used to apply a constant pressure of 2 kg/cm2 over a period of 5 minutes on the loaded custom tray. The pressure was recorded every 10 seconds. Factorial analysis of variance and Tukey's multiple comparison test were used to analyze the results. Results A significant difference in the pressure produced using different impression materials was found (p,0.001). Irreversible hydrocolloid and medium-body vinyl polysiloxane produced a significantly higher pressure than light-body vinyl polysiloxane and polysulfide impression materials. The presence of holes and/or relief did not significantly alter the magnitude of pressure. Conclusions All impression materials produced pressure during maxillary edentulous impression making. Tray modification was not important in changing the amount of pressure produced. The impression materials used had more effect on the pressure produced during impression making on the simulated oral analog. [source] Design principles for virtual patients: a focus group study among studentsMEDICAL EDUCATION, Issue 6 2009Sören Huwendiek Objectives, This study aimed to examine what students perceive as the ideal features of virtual patient (VP) design in order to foster learning with a special focus on clinical reasoning. Methods, A total of 104 Year 5 medical students worked through at least eight VPs representing four different designs during their paediatric clerkship. The VPs were presented in two modes and differed in terms of the authenticity of the user interface (with or without graphics support), predominant question type (long- versus short-menu questions) and freedom of navigation (relatively free versus predetermined). Each mode was presented in a rich and a poor version with regard to the use of different media and questions and explanations explicitly directed at clinical reasoning. Five groups of between four and nine randomly selected students (n = 27) participated in focus group interviews facilitated by a moderator using a questioning route. The interviews were videotaped, transcribed and analysed. Summary reports were approved by the students. Results, Ten principles of VP design emerged from the analysis. A VP should be relevant, of an appropriate level of difficulty, highly interactive, offer specific feedback, make optimal use of media, help students focus on relevant learning points, offer recapitulation of key learning points, provide an authentic web-based interface and student tasks, and contain questions and explanations tailored to the clinical reasoning process. Conclusions, Students perceived the design principles identified as being conducive to their learning. Many of these principles are supported by the results of other published studies. Future studies should address the effects of these principles using quantitative controlled designs. [source] Comparing different fractions of a factorial design: a metal cutting case studyAPPLIED STOCHASTIC MODELS IN BUSINESS AND INDUSTRY, Issue 2 2007E. Mønness Abstract Full factorial designs of a significant size are very rarely performed in industry due to the number of trials involved and unavailable time and resources. The data in this paper were obtained from a six-factor full factorial (26) designed experiment that was conducted to determine the optimum operating conditions for a steel milling operation. Fractional-factorial designs 2 (one-eighth) and 2 (one-fourth, using a fold-over from the one-eighth) are compared with the full 26 design. Four of the 2 are de-aliased by adding four more runs. In addition, two 12-run Plackett,Burman experiments and their combination into a fold-over 24-run experiment are considered. Many of the one-eighth fractional-factorial designs reveal some significant effects, but the size of the estimates varies much due to aliasing. Adding four more runs improves the estimation considerably. The one-quarter fraction designs yield satisfactory results, compared to the full factorial, if the ,correct' parameterization is assumed. The Plackett,Burman experiments, estimating all main effects, always perform worse than the equivalent regular designs (which have fewer runs). When considering a reduced model many of the different designs are more or less identical. The paper provides empirical evidence for managers and engineers that the choice of an experimental design is very important and highlights how designs of a minimal size may not always result in productive findings. Copyright © 2006 John Wiley & Sons, Ltd. [source] Numerical Simulation of Thrombus Aspiration in Two Realistic Models of Catheter TipsARTIFICIAL ORGANS, Issue 4 2010Giancarlo Pennati Abstract Thrombus aspiration catheters are devices used to remove a blood clot from a vessel, usually prior to angioplasty or stent implantation. However, in vitro results showed that the use of different commercial devices could produce very different thrombus removals, suggesting a primary dependence on the distal tip configuration of the catheter. A computational methodology based on realistic catheter tip modeling was developed to investigate the factors affecting the thrombus suction. Two different designs were considered, either with a single central lumen or a combination of central and side holes. First, steady-state aspiration of distilled water from a reservoir was simulated and compared with experimental tests. Subsequently, the aspiration of a totally occlusive thrombus, modeled as a high viscous fluid, was simulated solving a complex two-phase (blood and thrombus) problem. In particular, the benefit of additional openings was investigated. Good matching between the steady-state experimental and numerically simulated hydraulic behaviors allowed a validation of the numerical models. Numerical results of thrombus aspiration showed that the catheter with central and side holes had a worse performance if compared with the single central lumen catheter. Indeed, the inlets in contact with both blood and thrombus preferentially aspirate blood due to its much lower viscosity. This effect hindered the aspiration of thrombus. The amount of aspirated thrombus highly depends on the complex, two-phase fluid dynamics occurring across the catheter tips. Results suggested that location of additional holes is crucial in the catheter aspiration performance. [source] | |||||||||||||||||||