Photographic Measurements Research Articles

Visual Character of the Area Support Corridor: Case Study of the Great Mosque of Palembang

The Great Mosque of Palembang is one of the city centers, which visually is accessed by a corridor that gives value to the quality of the area, so it has the title, "Palembang City Center". By looking at the evaluation between the visual components of the mass composition in the corridor leading to an area, it can be seen the description of its character in supporting a regional center. Seeing visual signs through the arrangement and relationships between elements for each corridor, how to adjust the components of the visual system to one another, and what signs can appear in the visuals that will determine these components to be part of a system, so that they can manage character visually in support of a central area.

Localization Accuracy of Ultrasound-Actuated Needle with Color Doppler Imaging.

An ultrasonic needle-actuating device for tissue biopsy and regional anaesthesia offers enhanced needle visibility with color Doppler imaging. However, its specific performance is not yet fully determined. This work investigated the influence on needle visibility of the insertion angle and drive voltage, as well as determined the accuracy and agreement of needle tip localization by comparing color Doppler measurements with paired photographic and B-mode ultrasound measurements. Needle tip accuracy measurements in a gelatin phantom gave a regression trend, where the slope of trend is 0.8808; coefficient of determination (R2) is 0.8877; bias is −0.50 mm; and the 95% limits of agreement are from −1.31 to 0.31 mm when comparing color Doppler with photographic measurements. When comparing the color Doppler with B-mode ultrasound measurements, the slope of the regression trend is 1.0179; R2 is 0.9651; bias is −0.16 mm; and the 95% limits of agreement are from −1.935 to 1.605 mm. The results demonstrate the accuracy of this technique and its potential for application to biopsy and ultrasound guided regional anaesthesia.

Coupled conjugate heat transfer model for melting of PCM in cylindrical capsules

Phase change processes in latent heat thermal energy storage (LHTES) units are relevant, due to their ability in storing surplus power generated from renewable and conventional power plants. Macroencapsulation of phase change material (PCM) is one of several approaches to increase the mean discharging and charging power of such storage units. Numerical modelling and simulation in this context is a necessary alternative to rapid-prototyping to study solid-liquid phase change in latent heat thermal energy storage units. In this work, a numerical model is developed to represent the detailed thermal coupling between the heat transfer fluid (HTF) and phase change material capsules in a storage unit. An optimized iterative approach to represent the non-linear enthalpy-temperature and variable viscosity method for fixing and settling of solid phase in the capsule are employed in this work. Different computational domains for phase change material (PCM), heat transfer fluid (HTF) and capsule wall are employed, whose conjugated heat transfer is modelled in this work. A small representative latent heat thermal energy storage container is conceptualized to validate the developed conjugated heat transfer model. The melt front of phase change material is captured using photographic measurement in experiments over the complete melting time. The developed computational fluid dynamics (CFD) based conjugated heat transfer model has shown a very good agreement with experiments to estimate the heat transfer and melting of phase change material in the cylindrical capsule of a small scale latent heat thermal energy storage unit.

Behavior of the Delaware River Bridge during repair

This paper presents the behavior of the Delaware River Bridge, measured via the non-contact photographic measurement technique digital image correlation (DIC), as the bridge was repaired through vertical jacking and post-tensioning. Constructed in 1956 by American Bridge, the Delaware River Bridge is a continuous steel truss joining the New Jersey Turnpike and the Pennsylvania Turnpike. On January 20, 2017, a fracture was discovered in a W14 × 314 section in the upper chord of the north truss of the four-span continuous approach. The load redistributed to surrounding members, including a W14 × 87 upper chord member that buckled about its weak axis as well as adjacent verticals and sway bracing that deformed. Both the north and the south trusses also vertically deflected. The bridge was repaired by providing interim support using jacks on top of eight towers to stabilize the bridge. The fractured member was removed and replaced. Post-tensioning was used to restore the force in the replaced member and a permanent splice was installed. Throughout the repair, the full-field strains in the flanges of seven members near the fracture were monitored using DIC. Results indicate that the repair resulted in (1) uniaxial tension/compression in 6 of the 7 members and (2) flexural and axial tension strains in the buckled W14 × 87 upper chord member, all with magnitudes to be expected. This is the first application of DIC in monitoring a bridge during repair procedures and demonstrates the unprecedented information that DIC can provide on bridge behavior.

Photographic sagittal plane analysis and its clinical correlation after surgery for adult spinal deformity: a preliminary study.

The aim of this study is to determine the correlation between photographic sagittal parameters and patient-reported outcome measures (PROM) results in adult patients operated on spinal deformity. Non-concurrent prospective study. age at surgery older than 25, minimum 2-year follow-up after a 5 or more level fusion for adult spinal deformity (ASD). Full body lateral standing photographs were taken with adhesive markers placed on ten bony landmarks. SRS-22 and SF-36 questionnaires were completed for every patient. The following photographic parameters were measured: lumbar angle, lumbar curve, thoracic inclination (TI), trunk angle, pelvic tilt, head angle, neck angle, cervicothoracic angle, lumbar vector angle (LVA), dorsal vector angle (DVA), cervical vector angle (CVA), cranial pelvic angle (CrPA), cranial sacral angle (CrSA), fibular inclination angle (FIA) and cranial sagittal vertical axis measured to sacrum (Cr-S), greater trochanter (Cr-GT), knee (Cr-K) and ankle (Cr-A). 65 patients (58 female) operated on ASD in a single institution were included. Age at surgery was 61years (26-67). Postoperative follow-up was 53months (24-120). Spearman rank order test showed several significant (p ≤ 0.01) correlations. After multivariate linear regression analysis age, LVA and TI remained as predictors for SRS image scores (corrected r2 0.41), LVA for SRS satisfaction (corrected r2 0.27), CrPA and age for SRS total scores (corrected r2 0.33), FIA and age for SF36 physical functioning (corrected r2 0.36) and CrSA for SF36 role physical (corrected r2 0.14). Some sagittal photographic parameters may predict mid-term clinical results after ASD surgery.

What did Colonel Fabyan's acoustic anti-gravity device sound like?

Somewhere within the Geneva (Illinois) Museum of History, next to an old movie theater popcorn machine and closed up behind a false wall, is hidden one of the last surviving components of Colonel Fabyan's acoustic anti-gravity device. Originally built by textile magnate, George Fabyan under the guidance of pseudo-science practitioners, it is Professor Wallace Sabine's examination and quick debunking of the device's anti-gravity powers that is credited with the redirection of Colonel Fabyan's fortune to the creation of Riverbank Acoustical Laboratories and the legitimate scientific study of acoustics. Although the levitation device is not currently on display, the museum's Curator of Collections & Exhibitions gave a small group of acousticians the unique opportunity in 2019 to examine the device's existing components and supporting archival files. Although no one in the group was interested in the device's flying capabilities, everyone was curious what the device must have sounded like during Sabine's testing. Reviewing newspaper accounts of the period, taking photographic measurements of the existing components, using physical and computer modeling, acoustic testing and simulation; we present animation and auralization of Colonel Fabyan's acoustic anti-gravity device in the lab and in-flight.

Comparative Study of Presurgical Infant Orthopedics by Modified Grayson Method and Dynacleft With Nasal Elevators in Patients With Unilateral Cleft Lip and Palate—A Clinical Prospective Study

To compare the effects of presurgical infant orthopedics using 2 different methods, that is, the Dynacleft with Nasal elevator system versus the modified Grayson's technique in patients with complete unilateral cleft lip and palate. Prospective comparative cohort study. Twenty-eight patients were divided into 2 groups, that is, Group A consisting of 14 patients who underwent correction with DynaCleft with Nasal elevator system and Group B consisting of 14 patients undergoing correction using the modified Grayson technique. Maxillary cast measurements were taken at 2-time intervals (pre- and posttreatment) to assess various parameters using a laser scanning machine (C500 Solutionix) and 3D software (GOM Inspect). Similarly, standardized anterior-posterior and worm's-eye view photographs using a custom box were taken and imported to Adobe Photoshop CS6 for measurements. Paired t test and independent t test were used to compare intra- and intergroup changes, respectively. The analysis of cast (primary outcome) and photographic (secondary outcome) measurements showed improved nasal asymmetry and alveolar correction in both groups which showed no significant intergroup difference when assessed using the independent t test (P > .05). Group A showed higher chances (42.8%) of causing a T-shaped defect (due to excessive mesial-inward rotation of the minor segment) when compared to the Group B possibly due to a more controlled molding vector (P < .05). Both methods proved effective in improving the nasal asymmetry, reducing the alveolar cleft gap, and approximating the lips together; but care must be taken when applying the alveolar molding vector in the Dynacleft system.

Multi-projectiles Target Data Association Algorithm Based on D-S Evidence Theory

In the process of accuracy measurement of multi-projectile intersection target, aiming at the problem of multi-projectile target matching on two imaging planes of linear CCD(Charge Coupled Device), a Time-Dimension ICP(iterative closest point) iterative optimization data association algorithm is designed, and a data association decision algorithm based on D-S(Dempster-Shafer evidence theory) evidence reasoning is proposed. By analyzing the correlation error of multi-projectile target matching, the measure function of ICP iteration optimization is given. According to the basic principle of D-S evidential reasoning and the constraint relationship between two imaging surfaces of a multi-projectile online array camera, the design method of the basic probability assignment function of the number of data association, the mean value of absolute error and the consistency of error are given. According to D-S combination probability distribution, different data association results are reasoned and decided. By designing the distance error function from the point to the polar line, the method is extended to the area array high-speed photographic intersection measurement system. The simulation results show that the proposed algorithm can make effective judgments and give reliable data association results when the projectile data is missing, the projectile data is noisy and the projectile catches up.

Validity and Reliability of Electronic Head Posture Instrument for Measurement of Cranio-Horizontal Angle, Craniovertebral Angle and Sagittal Shoulder Angle

Background: Forward head posture (FHP) means that the head is in an anterior position in relation to the postural line and it is considered to coexist with hyperextension of upper cervical spine, flattening of lower cervical spine, rounding of the upper back and elevation and protraction of the shoulders. Because of associated problems, assessment of head posture has become increasingly important in clinical practices in evaluating and designing treatment regimens. For clinical diagnosis, angle measurements have been utilized as information for evaluating physical characteristics, determining the effects of rehabilitation and preventing injury induced by physical activity. There are various software’s available for measuring angles, one of them being Surgimap. In recent years, angle measurements using Electronic head posture instrument (EHPI) have been clinically researched as new angle measurement methods for the forward head posture apart from photographic measurement methods. Thus, this study evaluated the validity and reliability of the EHPI in measuring Head posture angles with Surgimap photograhic method in young healthy subjects. Methodology: Ethical approval for the study was granted and cross sectional observational study was conducted for validity and reliability at outpatient department. After written consent the subjects were made to understand the purpose of the study. Craniovertebral angle, Cranio-horizontal angle and Sagittal shoulder angle was measured using Electronic Head Posture Instrument and Photographic Method through Surgimap software. The research constituted of three researchers and intra rater reliability, inter rater reliability and validity was analyzed. Results: Data analysis was done using SPSS 20.0 version and the statistical significance level was set at p&lt;0.05. Intra rater reliability was found to be CHA=0. 95, CVA=0.92 and SSA=0.96, Inter rater reliability was found to be CHA= 0.98, CVA= 0.90 and SSA= 0.78. Correlation between different angles was found as CHA=0.95, CVA=0.79 and SSA=0.62. Conclusion: EHPI is a valid and reliable tool in clinically assessing and evaluating CHA, CVA and SSA

Nanosecond illumination source for speckle-free liquid crystalmicroscopy

ABSTRACT We present a setup for the speckle-free, low-light microscopy imaging at ~5 ns exposure times. The design is based on stroboscopic principle and uses fast and incoherent fluorescent emission from a dye, excited by a picosecond laser pulse. The basic spatial, spectral, and temporal beam properties are characterised, modelled and compared for two different designs of the source: (i) Rhodamine 6 G dye dissolved in ethanol and put in a glass cuvette, and (ii) random laser based on the dispersion of 300 nm TiO2 nanospheres in an ethanol solution of Rhodamine 6 G dye. The proposed solution of Rhodamine 6 G dye in ethanol put in a glass cuvette gives an excellent image quality with high contrast, excellent stability and tunable coherence. It delivers ~30 nJ of completely incoherent light per excitation laser pulse energy of ~40 μJ. It allows for the photographic measurements with 5 ns exposure time, demonstrated in imaging of thermally quenched 5CB liquid crystal. The set-up is used in studies of Kibble-Zurek mechanism of topological defect nucleation and growth at sub-microsecond time resolution and extremely fast cooling rates of ~40,000 K/s.

A novel rind puncture technique to measure rind thickness and diameter in plant stalks

BackgroundMeasurements of rind and culm thickness and stem radius/diameter are important to biomechanical, ecological and physiological plant studies. However, many methods of measuring rind thickness and diameter are labor intensive and induce plant fatality. A novel rind puncture methodology for obtaining measurements of rind thickness and diameter has been developed. The suitability of the new method for implementation in plant studies is presented.ResultsThe novel rind puncture technique was used to obtain measurements of rind thickness and diameter for samples of Poison Hemlock (Conium maculatum). The rind puncture measurements were strongly correlated with caliper measurements (R2 > 0.97) and photographic image analysis measurements (R2 > 0.84). The capacity for high throughput measurements using the rind puncture technique was determined to exceed that of caliper measurements and image analysis techniques.ConclusionsThe rind puncture technique shows promise as a high throughput method for determining rind thickness and diameter as it is cost effective and non-lethal. The authors are currently working to develop a custom handheld apparatus to allow the novel rind puncture method to be used in field work. High throughput field-based measurements of rind thickness and diameter are needed to help address the problem of stalk lodging (failure of grain crops to remain upright until harvest).

Crack detection in a beam using wavelet transform and photographic measurements

An optimistic attempt for the detection of a crack in a beam using discrete wavelet transform is proposed. Finite element model of the simply supported beam with a transverse open crack is considered. Crack in a beam causes a slope discontinuity in the elastic line. The deflection of the beam is used to locate the slope discontinuity using wavelet transform. The effect of measurement noise on the wavelet decomposition level is studied. An inexpensive digital image based technique is employed to obtain the deflection of the cracked beam for experimental investigations. White pixels due to dust particles are removed using connected component algorithm. A suitable edge detection technique is selected for finding the edged image on the basis of peak signal to noise ratio values. The deflection of the non-cracked edge of the beam is used as an input signal for wavelet transform to detect the crack location. Detection of a crack in the beam with different crack depths is investigated experimentally. The proposed method works well with numerically simulated as well as experimentally measured cracked beam deflections.

Main Factors Affecting the Photographic Determination of the Turbidity and Chromaticity of Water

The main factors that affect the performance characteristics of determining the turbidity and chromaticity of water by digital colorimetry in field (on-site) are studied. The test samples are suspensions of formazine and solutions composing the dichromate–cobalt chromaticity scale, which are used for calibration in standardized spectrophotometric methods for monitoring water quality. The affecting factors include the geometry of the vessel for colorimetric samples, the manufacturing quality of the adjustment device (drawing of chess fields), the method of fixing the camera in shooting, the method of performing the blank experiment, the illumination of the sample in shooting, the degree of cropping of the edges of the photograph of the chess fields in its digital processing, camera specifications, and the mutual effect of chromaticity and turbidity on the contrast of the photograph and its mean-root-square brightness. It is demonstrated that for the design of the on-site photographic measurements it is enough to have a digital camera, an adjustment device, and a measuring vessel. Photographing can be done with a camera held in hands. An empty measuring vessel may be used as an optically transparent sample for the blank experiment. Recommendations have been developed on optimizing the photographic measurements of turbidity and chromaticity. A possibility of the simultaneous determination of turbidity and chromaticity is shown by the example of monitoring the quality of tap water.

The effect of backpack load position on photographic measures of craniovertebral posture in 150 asymptomatic young adults.

Altering the horizontal position of the weight in a backpack will influence the magnitude of the external torque it creates but the effect on posture is unclear. To use photogrammetry to determine if changes in the horizontal position of a fixed backpack weight affect external measures of craniovertebral posture in 150 asymptomatic young adults. A backpack was attached to a steel frame with a bar protruding posteriorly. A fixed load (5% body mass) was placed at three distances along the bar -0 m, 0.20 m, and 0.40 m. Sagittal and frontal plane photogrammetry was used to measure the craniovertebral angle (CVA), upper cervical gaze angle (UCGA) and lateral head tilt angle (LHTA). A comparison was made across unloaded (no backpack) and loaded conditions. There was a significant decrease in the CVA between unloaded and loaded conditions. Changes in the UCGA were small and, while significant, may not have practical importance. There were no differences in the LHTA between the conditions. Changes in the horizontal position of a fixed load affect external measures of craniovertebral posture so consideration needs to be given to not only the weight of a backpack but how the weight is positioned within the backpack.

Long-term comparison study of philtral ridge morphology with two different techniques of philtral reconstruction

Cleft lip and/or cleft palate are the most common congenital craniofacial anomalies. Philtral ridge morphology is an important aesthetic component of unilateral cleft lip (UCL) repair. To this end, we have developed two techniques of philtral ridge reconstruction: (1) asymmetric mattress muscle sutures, and (2) overlapping mattress muscle sutures. The objective of this retrospective cohort study was to compare their outcomes in UCL repairs. Group I patients (n=30) underwent UCL repair before August 2003, including philtral ridge reconstruction by asymmetric mattress muscle sutures. Group II patients (n=30) underwent UCL repair after August 2003, including philtral ridge reconstruction by overlapping mattress muscle sutures. Philtral morphology was evaluated by ultrasonographic and three-dimensional photographic measurements, examining cleft side philtral projection and philtral ridge symmetry. These demonstrated that group II patients had better philtral column symmetry and projection on the cleft side when compared to group I. Overlapping mattress muscle sutures produced better philtral morphology in UCL repairs than asymmetric mattress muscle sutures.

Correlation between Cephalometric and Facial Photographic Measurements of Craniofacial Form-A Cross Sectional Study

Correlation between Cephalometric and Facial Photographic Measurements of Craniofacial Form-A Cross Sectional Study

An overview of in situ digital canopy photography in forestry

Since the 1960s, canopy photography has been widely used in forestry. Hemispherical photography has been the most widely used technique, but a great drawback of this method is its perceived sensitivity to hemispherical image acquisition and processing. Over the last decade, several alternative photographic approaches using restricted view angle have been proposed. Cover photography acquired via a normal lens was the first of the recently introduced photographic techniques. Use of a restricted view (often fixed) lens has subsequently contributed to the extension of canopy photography to new sensors and platforms, which ultimately have provided answers to some previous challenges regarding within-crown clumping correction, isolated and urban tree measurements, understory assessment, operational leaf inclination angle measurements, and phenological monitoring. This study provides a comprehensive review of the use of canopy photography in forestry and describes the theory and definitions of the variables used to quantify canopy structure. A case study is presented to illustrate and compare the different features and performance of the existing overstory photographic techniques; the results make it possible to suggest sampling strategies for consistent overstory canopy photographic measurements. Emerging operational fields of canopy photography are also described and discussed.

Research on Key Technology of UAV Low-altitude Photogrammetry

Photographic field control measurement is divided into the measurement of the basic control points of the regional network and the simultaneous measurement of the image control points and checkpoints. The main purpose is to connect the aerial camera coordinates with the ground control points, and then measure the plane according to the mathematical model. The accuracy of the point and elevation points, which in turn reflects the accuracy of the DOM digital product. Image control data directly reflects the accuracy of digital products. Therefore, it is necessary to perform joint control of image points. This paper mainly studies the key technologies of field control point layout and joint measurement, aerial triangulation and digital product generation.

The Use of Streak Photography, X-Ray Radiography, and Radiometric and Spectrometric Measurements to Study Plasma Bunches Generated under Gyroresonant Interactions

Results of experimental studies of relativistic plasma bunches obtained under gyromagnetic autoresonance (GA) and confined in a magnetic mirror trap are provided. The main attention is paid to observations of the radiation generated by plasma bunches at different stages of their lives in different spectral ranges using streak photography and X-ray imaging techniques. The original method of accounting for the instrument function in X-ray spectroscopic analysis and radiometric measurements is applied within the quantum energy range of 0.2–2 MeV to take account of considerable distortion caused by the Compton scattering in the detector.

Experimental study of the spontaneous imbibition characteristics of mudstone extracting water from cement grout

This study presents the imbibition characteristics of mudstone extracting water from cement grout. The pore-size distribution characteristics of the weak-cemented mudstone were obtained by some pore characteristic tests. The water distribution and migration of mudstone during imbibition with cement grout of different water-cement (W-C) ratios were tested by nuclear magnetic resonance (NMR), and surface deformation and water (from the cement grout) migration velocity (migration state) for mudstone samples with different initial water content were tested by digital photographic measurement (DPM) tests. The results showed that each T2 spectrum presented an isolated bimodal feature, and the left peak area was much larger than that of the right, indicating that the mudstone is mostly microporous, which confirms the pore characteristics of the mudstone obtained by scanning electron microscope, mercury intrusion porosimetry, and nitrogen adsorption desorption. The average slopes of the curves (signal amplitude and total area of the peak) increased with the increasing W-C ratios of grout, but the W-C ratio of 1 was a critical value for the imbibition capacity of mudstone extracting water from the cement grout. The deformation ranges of mudstone samples were very consistent with the ranges of spontaneous imbibition, and the deformation of the mudstone samples increased with the increasing imbibition time; the values of grout viscosities after the imbibition were all bigger than those of original cement grout. Moreover, the water migration velocities showed a trend of increasing and decreasing with the increase of W-C ratios of grout and the initial water content of mudstone samples at the same imbibition time.