Objectives-To determine (1) the combined effects of stress-field aspect ratio and velocity, and c... more Objectives-To determine (1) the combined effects of stress-field aspect ratio and velocity, and compressive strain, and (2) joint load, on TMJ disc mechanics Setting and Sample Population-Fifty-two subjects (30 ♀; 20 ♂) participated in the TMJ load experiments. Material and Methods-In the absence of human tissue, pig TMJ discs were used to determine the effects of variables (1) on surface plowing forces, and to build a biphasic finite element model (bFEM) to test the effect of human joint loads (2) on tissue stresses. In the laboratory, discs received a 7.6 N static load via an acrylic indenter before cyclic movement. Data were recorded and analyzed using ANOVA. To determine human joint loads (2), Research Diagnostic Criteria (RDC) calibrated investigators classified subjects based on signs of disc displacement (DD) and pain (+DD/+Pain, n=18; +DD/-Pain, n=17;-DD/-Pain, n=17). 3-D geometries were produced for each subject and used in a computer model to calculate joint loads. Results-The combined effects of compressive strain, and aspect ratio and velocity of stressfield translation correlated with plowing forces (R 2 =0.85). +DD/-Pain subjects produced 60% higher joint loads (ANOVA, P<0.05), which increased bFEM-calculated compressive strain and peak total normal stress. Conclusions-Static and dynamic variables of the stress-field and subject dependent joint load significantly affect disc mechanics.
Systemic simvastatin is known to reduce cholesterol and stimulate modest bone formation, but loca... more Systemic simvastatin is known to reduce cholesterol and stimulate modest bone formation, but local surgical placement in polylactic acid domes causes robust bone formation and local swelling. A less invasive and more flexible injection protocol was studied to evaluate the bone-inducing effects compared to surgical implantation. Bone formation rate, short-and long-term bone augmentation histology, and mechanical properties were evaluated to characterize the new bone in a rat bilateral mandible model (test and control sides in same animal). Results demonstrated that multiple (3) injections of 0.5 mg simvastatin effectively reduced soft tissue swelling while preserving bone growth (60% increase of bone width at 24 days) compared to simvastatin dome placement (43% increase at 24 days). Compared to controls, bone formation rate was significantly higher on the simvastatin side, especially in the dome. Three point bending tests revealed higher maximum force to fracture and stiffness at 24 days with simvastatin injections. Long-term evaluation showed that 55% of maximum new bone formed 24 days post-injection was retained at 90 days.
Distance education established its roots as a form of instruction at least 150 years ago as corre... more Distance education established its roots as a form of instruction at least 150 years ago as correspondence study . With the advancements in telecommunications technologies, distance learning programs rapidly expanded so distance education is now defined as "the acquisition of knowledge and skills through mediated information and instruction, encompassing all technologies and other forms of learning at a distance" (United States Distance Learning Association,1998).
Objective: To determine TMD diagnostic group differences in TMJ disc mechanics due to the effects... more Objective: To determine TMD diagnostic group differences in TMJ disc mechanics due to the effects of normal (perpendicular) load. Method: In accordance with IRB oversight, fifty-two subjects (30 female; 22 male) participated. Research Diagnostic Criteria-calibrated investigators classified subjects based on signs of disc displacement (DD) and pain (+DD/+Pain, n=18; +DD/-Pain, n=17; -DD/-Pain, n=17). 3-D craniomandibular geometries were produced for each subject and used in validated numerical models to calculate normal TMJ loads during biting on canine teeth. To test load effects on TMJ disc mechanics, ex vivo data were used in the development and validation of a biphasic finite element model (bFEM) of the TMJ disc. Given the scarcity of mechanical data from healthy human tissue, 187 freshly extracted pig TMJ discs were subjected to a 7.6 N static normal load, followed by cyclic movement. Physical data in the form of aspect ratio and velocity of stress-field translation, compressive...
The articulatory distinctiveness among vowels has been frequently characterized descriptively bas... more The articulatory distinctiveness among vowels has been frequently characterized descriptively based on tongue height and front-back position; however, very few empirical methods have been proposed to characterize vowels based on timevarying articulatory characteristics. Such information is not only needed to improve knowledge about the articulation of vowels but also to determine the contribution of articulatory imprecision to poor speech intelligibility. In this paper, a novel statistical shape analysis was used to derive a vowel space that depicted the quantified articulatory distinctiveness among vowels based on tongue and lip movements. The effectiveness of the approach was supported by vowel classification accuracy of up to 91.7%. The theoretical relevance and clinical implication of the derived vowel space were discussed.
Objective: It is unknown if variations in masticatory muscle orientation explain predicted TMD di... more Objective: It is unknown if variations in masticatory muscle orientation explain predicted TMD diagnostic group differences in lateral pterygoid muscle forces during static biting (Kohlmeier et al., 2012, J Dent Res, 91(SI A):578). Method: Research Diagnostic Criteria and magnetic resonance TMJ images were used by calibrated examiners to classify 93 subjects into 4 diagnostic groups based on presence(+) or absence (-) of disc displacement(DD) and pain [group, n=females, males: -DD/-pain, n=15, 13; -DD/+pain, n=8, 8; +DD/-pain, n=16, 13; +DD/+pain, n=15, 13). Subjects gave informed consent to participate in IRB-approved protocols. Three-dimensional geometries described positions of masticatory muscles, dental arches, and mandibular condyles for all subjects from lateral and posteroanterior cephalometric radiographs. The range of anteroposterior variations of masticatory muscle orientations represented (>1300 possible combinations) were used in 2 numerical models to identify key co...
Objective: Numerical modeling predicts higher TMJ forces for those with disc displacement (DD) co... more Objective: Numerical modeling predicts higher TMJ forces for those with disc displacement (DD) compared to healthy subjects (Iwasaki et al. 2009) and for increased muscle forces during jaw loading. Thus, this pilot study tested if individuals with/without temporomandibular disorders (TMDs) use their masticatory muscles similarly during molar biting. Methods: Subjects recruited gave informed consent to participate in IRB-approved protocols. Calibrated examiners used Research Diagnostic Criteria and TMJ magnetic resonance images to classify 71 subjects based on presence (+) or absence (-) of DD and pain into 3 groups (n=females,males): +DD/+pain (n=14,4), +DD/-pain (n=10,4), -DD/-pain (n=19,20). At each of 2 sessions, subjects performed standardized static and dynamic molar bites, 25 right and 25 left, on a calibrated transducer while bite-forces and surface electromyography from right masseter and anterior temporalis muscles were recorded. Slopes of electromyography (μV) versus bite-...
Objective: To test the hypothesis that during the day and night, masticatory muscle activities is... more Objective: To test the hypothesis that during the day and night, masticatory muscle activities is greater in individuals with temporomandibular disorders. Method: MRI and Research Diagnostic Criteria were used to categorize 71 informed and consenting subjects according to TMJ disc position (+DD = disc displacement) and pain status (+P = presence of pain). Male (n= 28) and female (n=42) subjects (+DD/+Pain, n=18; +DD/-Pain, n =14; -DD/-Pain, n=38) participated in two laboratory EMG/bite-force calibrations to determine subject-specific masseter and temporalis muscle threshold activities per 20 N bite-force (RMS20N, µV). Over 3 days subjects recorded day and night masseter and temporalis muscle activities using portable EMG recorders. Masseter and temporalis Duty Factors (DF = duration of muscle activity/total recording time, %) were determined based on muscle-specific thresholds of magnitude (5% to 80% RMS20N). ANOVA and Tukey-Kramer post-hoc tests were used to determine independent v...
Climate data are increasingly scrutinized for accuracy because of the need for reliable input for... more Climate data are increasingly scrutinized for accuracy because of the need for reliable input for climate-related decision making and assessments of climate change. Over the last 30 years, vast improvements to U.S. instrumentation, data collection, and station siting have created more accurate data. This study explores the spatial accuracy of daily maximum and minimum air temperature data in Nebraska networks, including the U.S. Historical Climatology Network (HCN), the Automated Weather Data Network (AWDN), and the more recent U.S. Climate Reference Network (CRN). The spatial structure of temperature variations at the earth's surface is compared for timeframes 2005-09 for CRN and AWDN and 1985-2005 for AWDN and HCN. Individual root-mean-square errors between candidate station and surrounding stations were calculated and used to determine the spatial accuracy of the networks. This study demonstrated that in the 5-yr analysis CRN and AWDN were of high spatial accuracy. For the 21...
Analysis of attractiveness of faces has long been a topic of research. Literature has identified ... more Analysis of attractiveness of faces has long been a topic of research. Literature has identified many different factors that can be related to attractiveness including symmetry, averageness, sexual dimorphism and adherence to the Golden Ratio. In this research we systematically analyze the role of three factors: symmetry, conformance to Neoclassical Canons and the Golden Ratio in the determination of attractiveness of a face. Unlike many researchers, we focus on the geometry of a face and use actual faces in standardized databases for our analysis. Our results are in agreement with the literature in that males and females generally agree on which faces are viewed as attractive and which are not. However, there are some differences in the criteria used by males and females to determine attractiveness. Using statistical analyses, we have developed a model to predict the attractiveness of a face using its geometry. The results show that our model is accurate with low residual errors.
Accuracy of techniques for recording the orientation of the maxillary arch to the articulation of... more Accuracy of techniques for recording the orientation of the maxillary arch to the articulation of the temporomandibular joints has been reported. The variability contributed by the dentist and the equipment within a technique may also contribute to technical error. This study investigated the variability of a group of dentists who used an arbitrary ear-face-bow instrument to mount a maxillary cast. The same maxillary cast on a single experimental subject was mounted on an articulator with a common arbitrary ear-face-bow instrument. This cast was equipped with 4 reference points for the measurement of changes of spatial orientation of the cast, which were determined through coordinate measurements with a machinist's microscope. A repeated measures analysis of variance was used to determine statistically significant changes in spatial orientation with a Wilks' Lambda test to compare mean values. A confidence interval of 95% demonstrated that any dentist might expect a range of...
2013 Abstracts IEEE International Conference on Plasma Science (ICOPS), 2013
ABSTRACT Pulsed electric field PEF is effective in inactivating microorganisms in liquids such as... more ABSTRACT Pulsed electric field PEF is effective in inactivating microorganisms in liquids such as saline water, phosphate buffer, milk and others. PEF treatment efficacy is influenced by number of parameters. Medium conductivity has been a subject of investigation because of the contrary reports. Present study was undertaken to systematic evaluate the effect of medium conductivity on the inactivation of E. coli. The experiments were conducted on E-coli innoculted phosphate buffer (2 to 4.5 mS/cm) in a continuous-flow co-field treatment chamber with an applied electric field strength of 60 kV/cm and 50 Hz pulse frequency. In the first set of experiments, the effect of medium conductivity on E-coli inactivation was evaluated at 49 μs treatment time. In the second set of experiments, the effect of medium conductivity was evaluated at constant specific energies of 54, 77 and 135 J/ mL. For the same treatment time, the microbial inactivation was higher in the buffer with higher electivity conductivity. Sub-lethal injury to E. coli. was observed in buffer PEF treatment. Even though the treatment times were different there was no significant effect of on the microbial inactivation to the different conductivity medium when the same specific energy was applied.
The main objective of this study was to identify if there is any change in wafer warpage after be... more The main objective of this study was to identify if there is any change in wafer warpage after bevel clean process, which might lead to higher film stress at device area in further processes. Correlation between bevel film Etch Rate (ER) and wafer warpage was also investigated. 25 kA thermal oxides (Tox) were etched on back side with various thicknesses
Fifth IEEE International Conference on Data Mining (ICDM'05), 2005
This paper studies how biologically meaningful landmarks extracted from face images can be exploi... more This paper studies how biologically meaningful landmarks extracted from face images can be exploited for face recognition using the bidimensional regression. Incorporating the correlation statistics of landmarks, this paper also proposes a new approach called eigenvalue weighted bidimensional regression. Complex principal component analysis is used for computing eigenvalues and removing correlation among landmarks. We evaluate our approach using two standard face databases: the Purdue AR and the NIST FERET. Experimental results show that the bidimensional regression is an efficient method to exploit geometry information of face images.
When a plate is placed in a thermoacoustic resonator, one extremity of the plate heats up while t... more When a plate is placed in a thermoacoustic resonator, one extremity of the plate heats up while the other cools down due to the thermoacoustic effect. In the present work the temperature difference between the extremities of the plate is calculated numerically. The computed temperature difference is compared to the one predicted by the linear theory. Some discrepancies are found even at low acoustic Mach numbers. These discrepancies can not be attributed to non-linear effects, rather they exist because of thermal effects. In particular the mean temperature in the fluid and in the plate are not equal. The discrepancies can be eliminated using corrective coefficients. Some deviations between the linear theory predictions and numerical results also occur at higher Mach numbers and are due to non-linearities, and especially temperature non-linearities that are generated in the vicinity of the plate.
Switchgrass (Panicum virgatum L.) is being developed into a perennial, herbaceous, cellulosic fee... more Switchgrass (Panicum virgatum L.) is being developed into a perennial, herbaceous, cellulosic feedstock crop for use in temperate regions of the USA. Information on spatial and temporal variation for stands and biomass yield among and within fields in large agroecoregions is not available. Spatial and temporal variation information is needed to model feedstock availability for biorefineries. In this 5-yr study, the spatial and temporal variation for biomass yield and stands was determined among and within 10 fields located in North Dakota, South Dakota, and Nebraska. Switchgrass fields were managed for bioenergy from 2000 to 2004 for the Nebraska locations and 2001 to 2005 for the South Dakota and North Dakota locations. A global positioning system (GPS) receiver was used to repeatedly measure within field quadrat sites for switchgrass stands using frequency grid (2.25 m 2 ) measurements in June for five growing seasons. Sixteen quadrat (≥1 m 2 ) yield samples were taken post-killing frost in the establishment year and in August in subsequent years at each location. Topographic within field effects on switchgrass stand frequency and biomass yields were largely insignificant. Stands tended to increase from establishment year to year 3 and then begin to plateau. Weather factors, which were the principal source of temporal variation, were more important in switchgrass yield variation than on switchgrass stand frequencies. Temporal standard deviations for yield were higher on quadrat sites with higher than average field means while temporal standard deviations were smaller in quadrat sites that had lower than average field means at six locations. In the Northern Great Plains agroecoregion, there is greater temporal and spatial variation for switchgrass biomass yields among fields than within fields. Results indicate that modeling feedstock availability for a biorefinery can be based on field scale yields.
Nutrient retention and dynamics with time in turfgrass sand-based rootzone mixtures (RZMs) are no... more Nutrient retention and dynamics with time in turfgrass sand-based rootzone mixtures (RZMs) are not well documented. This study was conducted to determine chemical properties of putting greens as im- pacted by (i) RZM, (ii) establishment (EST), and (iii) putting green age.UnitedStates Golf Association (USGA) specification greens were constructed and established with creeping bentgrass (Agrostis stolo- nifera L.) sequentially from 1997
ABSTRACT Due to the advances in imaging and storage technologies, the number and size of images c... more ABSTRACT Due to the advances in imaging and storage technologies, the number and size of images continue to grow at a rapid pace. This problem is particularly acute in the case of remotely sensed imagery. The continuous stream of sensory data from satellites poses major challenges in storage and retrieval of the satellite imagery. In the mean time, the ubiquity of Internet has resulted into an ever-growing population of users searching for various forms of information. In this paper, we describe the search engine SIMR—Satellite Image Matching and Retrieval system. SIMR provides an efficient means to match remotely sensed imagery. It computes spectral and spatial attributes of the images using a hierarchical representation. A unique aspect of our approach is the coupling of second-level spatial autocorrelation with quad tree structure. The efficiency of the web-based SIMR has been evaluated using a database of images with known characteristics: cities, towns, airports, lakes, and mountains. Results show that the integrated signature can be an effective basis for accurately searching databases of satellite based imagery.
Objectives-To determine (1) the combined effects of stress-field aspect ratio and velocity, and c... more Objectives-To determine (1) the combined effects of stress-field aspect ratio and velocity, and compressive strain, and (2) joint load, on TMJ disc mechanics Setting and Sample Population-Fifty-two subjects (30 ♀; 20 ♂) participated in the TMJ load experiments. Material and Methods-In the absence of human tissue, pig TMJ discs were used to determine the effects of variables (1) on surface plowing forces, and to build a biphasic finite element model (bFEM) to test the effect of human joint loads (2) on tissue stresses. In the laboratory, discs received a 7.6 N static load via an acrylic indenter before cyclic movement. Data were recorded and analyzed using ANOVA. To determine human joint loads (2), Research Diagnostic Criteria (RDC) calibrated investigators classified subjects based on signs of disc displacement (DD) and pain (+DD/+Pain, n=18; +DD/-Pain, n=17;-DD/-Pain, n=17). 3-D geometries were produced for each subject and used in a computer model to calculate joint loads. Results-The combined effects of compressive strain, and aspect ratio and velocity of stressfield translation correlated with plowing forces (R 2 =0.85). +DD/-Pain subjects produced 60% higher joint loads (ANOVA, P<0.05), which increased bFEM-calculated compressive strain and peak total normal stress. Conclusions-Static and dynamic variables of the stress-field and subject dependent joint load significantly affect disc mechanics.
Systemic simvastatin is known to reduce cholesterol and stimulate modest bone formation, but loca... more Systemic simvastatin is known to reduce cholesterol and stimulate modest bone formation, but local surgical placement in polylactic acid domes causes robust bone formation and local swelling. A less invasive and more flexible injection protocol was studied to evaluate the bone-inducing effects compared to surgical implantation. Bone formation rate, short-and long-term bone augmentation histology, and mechanical properties were evaluated to characterize the new bone in a rat bilateral mandible model (test and control sides in same animal). Results demonstrated that multiple (3) injections of 0.5 mg simvastatin effectively reduced soft tissue swelling while preserving bone growth (60% increase of bone width at 24 days) compared to simvastatin dome placement (43% increase at 24 days). Compared to controls, bone formation rate was significantly higher on the simvastatin side, especially in the dome. Three point bending tests revealed higher maximum force to fracture and stiffness at 24 days with simvastatin injections. Long-term evaluation showed that 55% of maximum new bone formed 24 days post-injection was retained at 90 days.
Distance education established its roots as a form of instruction at least 150 years ago as corre... more Distance education established its roots as a form of instruction at least 150 years ago as correspondence study . With the advancements in telecommunications technologies, distance learning programs rapidly expanded so distance education is now defined as "the acquisition of knowledge and skills through mediated information and instruction, encompassing all technologies and other forms of learning at a distance" (United States Distance Learning Association,1998).
Objective: To determine TMD diagnostic group differences in TMJ disc mechanics due to the effects... more Objective: To determine TMD diagnostic group differences in TMJ disc mechanics due to the effects of normal (perpendicular) load. Method: In accordance with IRB oversight, fifty-two subjects (30 female; 22 male) participated. Research Diagnostic Criteria-calibrated investigators classified subjects based on signs of disc displacement (DD) and pain (+DD/+Pain, n=18; +DD/-Pain, n=17; -DD/-Pain, n=17). 3-D craniomandibular geometries were produced for each subject and used in validated numerical models to calculate normal TMJ loads during biting on canine teeth. To test load effects on TMJ disc mechanics, ex vivo data were used in the development and validation of a biphasic finite element model (bFEM) of the TMJ disc. Given the scarcity of mechanical data from healthy human tissue, 187 freshly extracted pig TMJ discs were subjected to a 7.6 N static normal load, followed by cyclic movement. Physical data in the form of aspect ratio and velocity of stress-field translation, compressive...
The articulatory distinctiveness among vowels has been frequently characterized descriptively bas... more The articulatory distinctiveness among vowels has been frequently characterized descriptively based on tongue height and front-back position; however, very few empirical methods have been proposed to characterize vowels based on timevarying articulatory characteristics. Such information is not only needed to improve knowledge about the articulation of vowels but also to determine the contribution of articulatory imprecision to poor speech intelligibility. In this paper, a novel statistical shape analysis was used to derive a vowel space that depicted the quantified articulatory distinctiveness among vowels based on tongue and lip movements. The effectiveness of the approach was supported by vowel classification accuracy of up to 91.7%. The theoretical relevance and clinical implication of the derived vowel space were discussed.
Objective: It is unknown if variations in masticatory muscle orientation explain predicted TMD di... more Objective: It is unknown if variations in masticatory muscle orientation explain predicted TMD diagnostic group differences in lateral pterygoid muscle forces during static biting (Kohlmeier et al., 2012, J Dent Res, 91(SI A):578). Method: Research Diagnostic Criteria and magnetic resonance TMJ images were used by calibrated examiners to classify 93 subjects into 4 diagnostic groups based on presence(+) or absence (-) of disc displacement(DD) and pain [group, n=females, males: -DD/-pain, n=15, 13; -DD/+pain, n=8, 8; +DD/-pain, n=16, 13; +DD/+pain, n=15, 13). Subjects gave informed consent to participate in IRB-approved protocols. Three-dimensional geometries described positions of masticatory muscles, dental arches, and mandibular condyles for all subjects from lateral and posteroanterior cephalometric radiographs. The range of anteroposterior variations of masticatory muscle orientations represented (>1300 possible combinations) were used in 2 numerical models to identify key co...
Objective: Numerical modeling predicts higher TMJ forces for those with disc displacement (DD) co... more Objective: Numerical modeling predicts higher TMJ forces for those with disc displacement (DD) compared to healthy subjects (Iwasaki et al. 2009) and for increased muscle forces during jaw loading. Thus, this pilot study tested if individuals with/without temporomandibular disorders (TMDs) use their masticatory muscles similarly during molar biting. Methods: Subjects recruited gave informed consent to participate in IRB-approved protocols. Calibrated examiners used Research Diagnostic Criteria and TMJ magnetic resonance images to classify 71 subjects based on presence (+) or absence (-) of DD and pain into 3 groups (n=females,males): +DD/+pain (n=14,4), +DD/-pain (n=10,4), -DD/-pain (n=19,20). At each of 2 sessions, subjects performed standardized static and dynamic molar bites, 25 right and 25 left, on a calibrated transducer while bite-forces and surface electromyography from right masseter and anterior temporalis muscles were recorded. Slopes of electromyography (μV) versus bite-...
Objective: To test the hypothesis that during the day and night, masticatory muscle activities is... more Objective: To test the hypothesis that during the day and night, masticatory muscle activities is greater in individuals with temporomandibular disorders. Method: MRI and Research Diagnostic Criteria were used to categorize 71 informed and consenting subjects according to TMJ disc position (+DD = disc displacement) and pain status (+P = presence of pain). Male (n= 28) and female (n=42) subjects (+DD/+Pain, n=18; +DD/-Pain, n =14; -DD/-Pain, n=38) participated in two laboratory EMG/bite-force calibrations to determine subject-specific masseter and temporalis muscle threshold activities per 20 N bite-force (RMS20N, µV). Over 3 days subjects recorded day and night masseter and temporalis muscle activities using portable EMG recorders. Masseter and temporalis Duty Factors (DF = duration of muscle activity/total recording time, %) were determined based on muscle-specific thresholds of magnitude (5% to 80% RMS20N). ANOVA and Tukey-Kramer post-hoc tests were used to determine independent v...
Climate data are increasingly scrutinized for accuracy because of the need for reliable input for... more Climate data are increasingly scrutinized for accuracy because of the need for reliable input for climate-related decision making and assessments of climate change. Over the last 30 years, vast improvements to U.S. instrumentation, data collection, and station siting have created more accurate data. This study explores the spatial accuracy of daily maximum and minimum air temperature data in Nebraska networks, including the U.S. Historical Climatology Network (HCN), the Automated Weather Data Network (AWDN), and the more recent U.S. Climate Reference Network (CRN). The spatial structure of temperature variations at the earth's surface is compared for timeframes 2005-09 for CRN and AWDN and 1985-2005 for AWDN and HCN. Individual root-mean-square errors between candidate station and surrounding stations were calculated and used to determine the spatial accuracy of the networks. This study demonstrated that in the 5-yr analysis CRN and AWDN were of high spatial accuracy. For the 21...
Analysis of attractiveness of faces has long been a topic of research. Literature has identified ... more Analysis of attractiveness of faces has long been a topic of research. Literature has identified many different factors that can be related to attractiveness including symmetry, averageness, sexual dimorphism and adherence to the Golden Ratio. In this research we systematically analyze the role of three factors: symmetry, conformance to Neoclassical Canons and the Golden Ratio in the determination of attractiveness of a face. Unlike many researchers, we focus on the geometry of a face and use actual faces in standardized databases for our analysis. Our results are in agreement with the literature in that males and females generally agree on which faces are viewed as attractive and which are not. However, there are some differences in the criteria used by males and females to determine attractiveness. Using statistical analyses, we have developed a model to predict the attractiveness of a face using its geometry. The results show that our model is accurate with low residual errors.
Accuracy of techniques for recording the orientation of the maxillary arch to the articulation of... more Accuracy of techniques for recording the orientation of the maxillary arch to the articulation of the temporomandibular joints has been reported. The variability contributed by the dentist and the equipment within a technique may also contribute to technical error. This study investigated the variability of a group of dentists who used an arbitrary ear-face-bow instrument to mount a maxillary cast. The same maxillary cast on a single experimental subject was mounted on an articulator with a common arbitrary ear-face-bow instrument. This cast was equipped with 4 reference points for the measurement of changes of spatial orientation of the cast, which were determined through coordinate measurements with a machinist's microscope. A repeated measures analysis of variance was used to determine statistically significant changes in spatial orientation with a Wilks' Lambda test to compare mean values. A confidence interval of 95% demonstrated that any dentist might expect a range of...
2013 Abstracts IEEE International Conference on Plasma Science (ICOPS), 2013
ABSTRACT Pulsed electric field PEF is effective in inactivating microorganisms in liquids such as... more ABSTRACT Pulsed electric field PEF is effective in inactivating microorganisms in liquids such as saline water, phosphate buffer, milk and others. PEF treatment efficacy is influenced by number of parameters. Medium conductivity has been a subject of investigation because of the contrary reports. Present study was undertaken to systematic evaluate the effect of medium conductivity on the inactivation of E. coli. The experiments were conducted on E-coli innoculted phosphate buffer (2 to 4.5 mS/cm) in a continuous-flow co-field treatment chamber with an applied electric field strength of 60 kV/cm and 50 Hz pulse frequency. In the first set of experiments, the effect of medium conductivity on E-coli inactivation was evaluated at 49 μs treatment time. In the second set of experiments, the effect of medium conductivity was evaluated at constant specific energies of 54, 77 and 135 J/ mL. For the same treatment time, the microbial inactivation was higher in the buffer with higher electivity conductivity. Sub-lethal injury to E. coli. was observed in buffer PEF treatment. Even though the treatment times were different there was no significant effect of on the microbial inactivation to the different conductivity medium when the same specific energy was applied.
The main objective of this study was to identify if there is any change in wafer warpage after be... more The main objective of this study was to identify if there is any change in wafer warpage after bevel clean process, which might lead to higher film stress at device area in further processes. Correlation between bevel film Etch Rate (ER) and wafer warpage was also investigated. 25 kA thermal oxides (Tox) were etched on back side with various thicknesses
Fifth IEEE International Conference on Data Mining (ICDM'05), 2005
This paper studies how biologically meaningful landmarks extracted from face images can be exploi... more This paper studies how biologically meaningful landmarks extracted from face images can be exploited for face recognition using the bidimensional regression. Incorporating the correlation statistics of landmarks, this paper also proposes a new approach called eigenvalue weighted bidimensional regression. Complex principal component analysis is used for computing eigenvalues and removing correlation among landmarks. We evaluate our approach using two standard face databases: the Purdue AR and the NIST FERET. Experimental results show that the bidimensional regression is an efficient method to exploit geometry information of face images.
When a plate is placed in a thermoacoustic resonator, one extremity of the plate heats up while t... more When a plate is placed in a thermoacoustic resonator, one extremity of the plate heats up while the other cools down due to the thermoacoustic effect. In the present work the temperature difference between the extremities of the plate is calculated numerically. The computed temperature difference is compared to the one predicted by the linear theory. Some discrepancies are found even at low acoustic Mach numbers. These discrepancies can not be attributed to non-linear effects, rather they exist because of thermal effects. In particular the mean temperature in the fluid and in the plate are not equal. The discrepancies can be eliminated using corrective coefficients. Some deviations between the linear theory predictions and numerical results also occur at higher Mach numbers and are due to non-linearities, and especially temperature non-linearities that are generated in the vicinity of the plate.
Switchgrass (Panicum virgatum L.) is being developed into a perennial, herbaceous, cellulosic fee... more Switchgrass (Panicum virgatum L.) is being developed into a perennial, herbaceous, cellulosic feedstock crop for use in temperate regions of the USA. Information on spatial and temporal variation for stands and biomass yield among and within fields in large agroecoregions is not available. Spatial and temporal variation information is needed to model feedstock availability for biorefineries. In this 5-yr study, the spatial and temporal variation for biomass yield and stands was determined among and within 10 fields located in North Dakota, South Dakota, and Nebraska. Switchgrass fields were managed for bioenergy from 2000 to 2004 for the Nebraska locations and 2001 to 2005 for the South Dakota and North Dakota locations. A global positioning system (GPS) receiver was used to repeatedly measure within field quadrat sites for switchgrass stands using frequency grid (2.25 m 2 ) measurements in June for five growing seasons. Sixteen quadrat (≥1 m 2 ) yield samples were taken post-killing frost in the establishment year and in August in subsequent years at each location. Topographic within field effects on switchgrass stand frequency and biomass yields were largely insignificant. Stands tended to increase from establishment year to year 3 and then begin to plateau. Weather factors, which were the principal source of temporal variation, were more important in switchgrass yield variation than on switchgrass stand frequencies. Temporal standard deviations for yield were higher on quadrat sites with higher than average field means while temporal standard deviations were smaller in quadrat sites that had lower than average field means at six locations. In the Northern Great Plains agroecoregion, there is greater temporal and spatial variation for switchgrass biomass yields among fields than within fields. Results indicate that modeling feedstock availability for a biorefinery can be based on field scale yields.
Nutrient retention and dynamics with time in turfgrass sand-based rootzone mixtures (RZMs) are no... more Nutrient retention and dynamics with time in turfgrass sand-based rootzone mixtures (RZMs) are not well documented. This study was conducted to determine chemical properties of putting greens as im- pacted by (i) RZM, (ii) establishment (EST), and (iii) putting green age.UnitedStates Golf Association (USGA) specification greens were constructed and established with creeping bentgrass (Agrostis stolo- nifera L.) sequentially from 1997
ABSTRACT Due to the advances in imaging and storage technologies, the number and size of images c... more ABSTRACT Due to the advances in imaging and storage technologies, the number and size of images continue to grow at a rapid pace. This problem is particularly acute in the case of remotely sensed imagery. The continuous stream of sensory data from satellites poses major challenges in storage and retrieval of the satellite imagery. In the mean time, the ubiquity of Internet has resulted into an ever-growing population of users searching for various forms of information. In this paper, we describe the search engine SIMR—Satellite Image Matching and Retrieval system. SIMR provides an efficient means to match remotely sensed imagery. It computes spectral and spatial attributes of the images using a hierarchical representation. A unique aspect of our approach is the coupling of second-level spatial autocorrelation with quad tree structure. The efficiency of the web-based SIMR has been evaluated using a database of images with known characteristics: cities, towns, airports, lakes, and mountains. Results show that the integrated signature can be an effective basis for accurately searching databases of satellite based imagery.
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Papers by David Marx