Inclination Measurements Research Articles

Investigation of the reproducibility and reliability of sagittal vertebral inclination measurements from MR images of the spine

In this study, sagittal vertebral inclination (SVI) was systematically evaluated for 28 vertebrae (segments between T4 and L5) in magnetic resonance (MR) images of one normal and one scoliotic subject to compare the performance of manual and computerized measurements, and identify the most reproducible and reliable measurements. Manual measurements were performed by three observers, who identified on two occasions the distinctive anatomical landmarks required to evaluate SVI by six measurement methods, i.e. the superior tangents, inferior tangents, anterior tangents, posterior tangents, mid-endplate lines and mid-wall lines. Computerized measurements were performed by automatically evaluating SVI from the symmetry of vertebral anatomical structures in two-dimensional (2D) sagittal cross-sections and in three-dimensional (3D) volumetric images. The mid-wall lines and posterior tangents proved to be the manual measurements with the lowest intra-observer (standard deviation, SD, of 1.4° and 1.7°, respectively) and inter-observer variability (SD of 1.9° and 2.4°, respectively). The strongest inter-method agreement was found between the mid-wall lines and posterior tangents (SD of 2.0°). Computerized measurements in 2D and in 3D resulted in intra-observer (SD of 2.8° and 3.1°, respectively) and inter-observer variability (SD of 3.8° and 5.2°, respectively) that were comparable to those of the superior tangents (SD of 2.6° and 3.7°) and inferior tangents (SD of 3.2° and 4.5°), which represent standard Cobb angle measurements. It can be concluded that computerized measurements of SVI should be based on the inclination of vertebral body walls.

Comparison of orthodontic treatment outcomes in nonextraction, 2 maxillary premolar extraction, and 4 premolar extraction protocols with the American Board of Orthodontics objective grading system

The aim of this study was to compare the orthodontic clinical outcomes of 2 maxillary premolar extraction, 4 premolar extraction, and nonextraction treatment protocols. The sample for this retrospective study was selected randomly from the archives of postgraduate orthodontic clinics in various cities in Turkey. Posttreatment records including dental casts and panoramic radiographs of 1098 patients were divided into 3 groups: group 1 comprised 269 patients treated with 2 maxillary first premolar extraction, group 2 comprised 267 patients treated with 4 premolar extraction, and group 3 comprised 562 patients treated with a nonextraction protocol. Only 1 researcher evaluated all subjects using the American Board of Orthodontics objective grading system. There were no statistically significant differences among the 2 maxillary premolar extraction, 4 premolar extraction, and nonextraction treatment groups for alignment, marginal ridge height, buccolingual inclination, overjet, and interproximal contact measurements. Statistically significant differences were found in occlusal contacts, occlusal relationships, and root angulation measurements between the 4 premolar extraction and the nonextraction groups. The nonextraction patients had more teeth in occlusion than did the 4 premolar extraction patients. The nonextraction patients finished with more satisfactory sagittal dental relationships. The 4 premolar extraction group had the least satisfactory sagittal dental relationships. The nonextraction patients finished with better root angulations.

An Optimization Model and Genetic Algorithm Solution for Automated Celestial Navigation of Ships

Inclination measurement errors have a significant effect on the positioning accuracy of an automated ship celestial navigation system using the existing theoretical models. To reduce such undesirable effect, we propose a nonlinear least-squares model based on global optimization and provide a genetic algorithm solution using proportional selection, arithmetical crossover, Gaussian mutation, and elitist strategy. The performance of the model and solution is demonstrated by an instance of simulation experiment. The results indicate that the global near-optimal solution of a ship’s attitude and position can be obtained with accuracy of arc-second level, and the accuracy is better than that of the existing models by one to two orders of magnitude under the same measurement conditions.

Design of Guided Shell Inclination Measurement and Display System Based-on MEMS Accelerometer

Based on the analysis of inclination principle Using MEMS acceleration sensor,we design the divided voltage circuit and regulating circuit.This article based on the MCU minimum system,using MEMS acceleration sensor for development and application, and the angle information can be displayed by LCD or PC.The inclination measurement precision can reach ± 0.2 °,so it can be used for measuring the pose of guided shell , airplane, missiles and other aerocraft construction, also can be used in geological exploration and other fields.

Measurements of the sagittal condylar inclination: intraindividual variations

Aims: Sagittal condylar inclination is an important parameter during fabrication of prosthetic restorations. Existing data about intraindividual variations of sagittal condylar inclination are scarce. The purpose of this study was to investigate intra- and interindividual variations of the sagittal condylar inclination, depending on the position of the condyle in the temporomandibular joint.Methodology: The study included 51 subjects with Angle’s Class I occlusion (21–32 years of age, mean 25·1). Measurements were done using an electronic axiograph. After a paraocclusal tray was fixed in the mouth, every subject had to make three protrusive movements, from which the device’s software calculated the mean left and mean right sagittal condylar path. The mean left and right condylar path of each subject was divided into three equal sequences, based on whole condylar path length. Condylar inclination values for the first, second and third movement sequences were calculated.Results: Results showed significant differences between movement sequences (P<0·05). For the left joint, condylar inclination values in the first condylar movement sequence demonstrated, on the average, 14·4% higher values compared to the second movement sequence, and 39·2% higher values than in the third movement sequence. For the right joint, the first condylar movement sequence demonstrated, on the average, 15·8% higher values compared to the second movement sequence, and 41·5% higher values than the third movement sequence.Conclusions: Results suggest that condylar movement in the sagittal direction is not uniform. Mean left and mean right condylar inclination values do not necessarily describe the actual condylar path, nor do they give adequate information for articulator setup. Left–right side condylar inclination differences greater than 10° can be considered as normal.

WHAT ASTEROSEISMOLOGY CAN DO FOR EXOPLANETS: KEPLER-410A b IS A SMALL NEPTUNE AROUND A BRIGHT STAR, IN AN ECCENTRIC ORBIT CONSISTENT WITH LOW OBLIQUITY

We confirm the Kepler planet candidate Kepler-410b (KOI-42b) as a Neptune sized exoplanet on a 17.8 day, eccentric orbit around the bright (Kp = 9.4) star Kepler-410A. This is the third brightest confirmed planet host star in the Kepler field and one of the brightest hosts of all currently known transiting exoplanets. Kepler-410 consists of a blend between the fast rotating planet host star (Kepler-410A) and a fainter star (Kepler-410B), which has complicated the confirmation of the planetary candidate. Employing asteroseismology, using constraints from the transit light curve, adaptive optics and speckle images, and Spitzer transit observations, we demonstrate that the candidate can only be an exoplanet orbiting Kepler-410A. Via asteroseismology we determine the following stellar and planetary parameters with high precision; M$_\star = 1.214 \pm 0.033$ M$_\odot$, R$_\star = 1.352 \pm 0.010$ R$_\odot$, Age = $2.76 \pm 0.54$ Gyr, planetary radius ($2.838 \pm 0.054$ R$_\oplus$), and orbital eccentricity ($0.17^{+0.07}_{-0.06}$). In addition, rotational splitting of the pulsation modes allows for a measurement of Kepler-410A's inclination and rotation rate. Our measurement of an inclination of $82.5^{+7.5}_{-2.5}$ [$^\circ$] indicates a low obliquity in this system. Transit timing variations indicate the presence of at least one additional (non-transiting) planet in the system.

阮朝フエ王宮における世祖廟の寸法計画について

To restore Thai To Mieu, we researched the measurement plan of The To Mieu to establish the restoration method. The conclusion of this paper is as follows. : 1. There are basic plan that the column compartment of “moya” is 10 units, the column compartment of “hisashi” and “mokoshi” is 8 units (=the standard column compartment multiplied by 0.8) in the ground plan of The To Mieu. The actual column compartment was decided on adding the measure of column inclination to the basic column compartment. 2. The diameter of “moya” column was decided on multiplying 1/10 to “moya” column compartment in Chinh Dien. The difference between the diameter of “moya” and “mokoshi” column is 0.1 units. 3. In the section plan of The To Mieu, the height of column and ridge were decided on the “moya”, “hisashi” and “mokoshi” column compartment. 4. The measure of column expansion was about 0.15 units, and there is a possibility to have been changed when repairing The To Mieu.

Fabrication and Characterization of High Performance Micro Impedance Inclinometer

Abstract In the study, a novel micro impedance inclinometer is presented, consisting of a glass substrate, Cr electrodes and a mercury pendulum. The output signal of the proposed inclinometer is read from the moving metal pendulum based on an LED array measurement scheme. A mercury pendulum mass is used for the inclinometer. The adhesion between the liquid metal and the substrate surface is reduced by etching or sandblasting the substrate surface. Experimental results show the developed inclinometer has a high angle resolution (0.3°), a rapid time response (385 ms) and a high repeatability (R2 = 0.9988) with the A280# sandblasted substrate surface and the mercury pendulum of 360 μl. The developed inclinometer provide a simply yet high-performance solution for the inclination measurement.

Development of Perpendicular Sensor for Disaster Prevention

Monitoring of inclination of land is important to prevent damage from landslide. Low cost and stable system is necessary for this purpose. This paper presents a new inclination measurement system and its application to sensor network of disaster prevention. Our system has a bull's eye level, a digital camera and wireless module. The angle and direction of inclination is measured from the photo of bull's eye level. The achieved resolution was 0.0053degree/pixel using a bull's eye level with a curvature radius of 800 mm. Measurement data was compared with the data from commercial inclinometer.

다용도 실시간 경사각과 방위각 연속 측정 시스템 개발연구

최근 지구물리 물리탐사 분야에서 경사각과 방위각 정보는 시추공 물리검층 및 물리탐사 자료보정을 위한 시추공 편차검층, 이동형 실시간 자료획득 시스템, 기타 지구물리 모니터링 시스템 등 다양하게 활용되면서 그 중요성이 높아지고 있다. 특히 최근 셰일가스의 개발이 가능하게 한 방향시추 기술에서도 경사각과 방위각 정보는 필수일 정도로 그 응용범위가 매우 넓다. 따라서 여러 분야에 응용될 수 있는 경사각과 방위각 측정 시스템의 초소형 옥외 저전력 운용이 절실해졌다. 본 논문에서는 최신 CMOS 저전력, 고성능 MCU 및 멤스(MEMS) 자세방위기준장치(AHRS)를 도입하여 초소형, 저전력으로 제작된 다용도 야외시험용 실시간 경사각과 방위각 연속 측정 시스템 개발 연구의 결과를 제시하고자 한다. 시스템은 최소 지름 42 mm의 존데 내에 설치될 수 있도록 초슬림 형태로 제작되었으며 실시간 데이터 획득이 가능할 뿐만 아니라 엔코더, DGPS 연동으로 운용 확장이 가능하여 다양한 응용이 기대된다. In geophysics and geophysical exploration fields, we can use information about inclination and azimuth in various ways. These include borehole deviation logging for inversion process, real-time data acquisition system, geophysical monitoring system, and so on. This type of information is also necessarily used in the directional drilling of shale gas fields. We thus need to develop a subminiature, low-powered, multi-functional inclination and azimuth measurement system for geophysical exploration fields. In this paper, to develop real-time measurement system, we adopt the high performance low power Micro Control Unit (made with state-of-the-art Complementary Metal Oxide Semiconductor technology) and newly released Micro Electro Mechanical Systems Attitude Heading Reference System sensors. We present test results on the development of a multifunctional real-time inclination and azimuth measurement system. The developed system has an ultra-slim body so as to be installed in 42mm sonde. Also, this system allows us to acquire data in real-time and to easily expand its application by synchronizing with a depth encoder or Differential Global Positioning System.

Comparison of Parameters of Spinal Curves in the Sagittal Plane Measured by Photogrammetry and Inclinometry

BACKGROUND. The photogrammetric method and inclinometer-based measurements are commonly employed to assess the anteroposterior curvatures of the spine. These methods are used both in clinical trials and for screening purposes. The aim of the study was to compare the parameters used to characterise the anteroposterior spinal curvatures as measured by photogrammetry and inclinometry. MATERIAL AND METHODS. The study enrolled 341 subjects: 169 girls and 172 boys, aged 4 to 9 years, from kindergartens and primary schools in Rzeszów. The anteroposterior spinal curvatures were examined by photogrammetry and with a mechanical inclinometer. RESULTS. There were significant differences in the α angle between the inclinometric and photogrammetric assessment in the Student t test (p=0.017) and the Fisher Snedecor test (p=0.0001), with similar differences in the β angle (Student's t p=0.0001, Fisher Snedecor p=0.007). For the γ angle, significant differences were revealed with Student's t test (p=0.0001), but not with the Fisher Snedecor test (p = 0.22). CONCLUSIONS. 1. Measurements of inclination of particular segments of the spine obtained with the photogrammetric method and the inclinometric method in the same study group revealed statistically significant differences. 2. The results of measurements obtained by photogrammetry and inclinometry are not comparable. 3. Further research on agreement between measurements of the anteroposterior spinal curvatures obtained using the available measurement equipment is recommended.

PRECISE TULLY-FISHER RELATIONS WITHOUT GALAXY INCLINATIONS

Power-law relations between tracers of baryonic mass and rotational velocities of disk galaxies, so-called Tully–Fisher relations (TFRs), offer a wealth of applications in galaxy evolution and cosmology. However, measurements of rotational velocities require galaxy inclinations, which are difficult to measure, thus limiting the range of TFR studies. This work introduces a maximum likelihood estimation (MLE) method for recovering the TFR in galaxy samples with limited or no information on inclinations. The robustness and accuracy of this method is demonstrated using virtual and real galaxy samples. Intriguingly, the MLE reliably recovers the TFR of all test samples, even without using any inclination measurements—that is, assuming a random sin i-distribution for galaxy inclinations. Explicitly, this "inclination-free MLE" recovers the three TFR parameters (zero-point, slope, scatter) with statistical errors only about 1.5 times larger than the best estimates based on perfectly known galaxy inclinations with zero uncertainty. Thus, given realistic uncertainties, the inclination-free MLE is highly competitive. If inclination measurements have mean errors larger than 10°, it is better not to use any inclinations than to consider the inclination measurements to be exact. The inclination-free MLE opens interesting perspectives for future H i surveys by the Square Kilometer Array and its pathfinders.

A Newly Developed Self-Contained Inclinometer for Offshore Platform Anchor Monitoring

This paper presents the research and development of a special self-contained Inclinometer based on the requirement of offshore platform monitoring. The device records the anchors inclination completely and accurately, providing information for stress analysis of the anchor chain. Laboratory calibration, platform movement simulation experiment, and real platform testing confirmed the instrument can meet the measurement requirements. The instrument is high-precision, energy-economical, mass-storage and user-friendly. Its able to work underwater continuously for up to one year. In addition, the small size minimizes the interference caused by the carriers motion. Compared with its foreign counterparts, the new instrument is inexpensive, so its suitable for extensive multi-point measurement. Now it has been installed in LH11-1 platform in the South China Sea for measurement of anchor chain inclination. Its the first time to employ measuring device with autonomous right in offshore platform monitoring in China.

Is there an association between the individual anatomy of the scapula and the development of rotator cuff tears or osteoarthritis of the glenohumeral joint?

We hypothesised that a large acromial cover with an upwardly tilted glenoid fossa would be associated with degenerative rotator cuff tears (RCTs), and conversely, that a short acromion with an inferiorly inclined glenoid would be associated with glenohumeral osteoarthritis (OA). This hypothesis was tested using a new radiological parameter, the critical shoulder angle (CSA), which combines the measurements of inclination of the glenoid and the lateral extension of the acromion (the acromion index). The CSA was measured on standardised radiographs of three groups: 1) a control group of 94 asymptomatic shoulders with normal rotator cuffs and no OA; 2) a group of 102 shoulders with MRI-documented full-thickness RCTs without OA; and 3) a group of 102 shoulders with primary OA and no RCTs noted during total shoulder replacement. The mean CSA was 33.1° (26.8° to 38.6°) in the control group, 38.0° (29.5° to 43.5°) in the RCT group and 28.1° (18.6° to 35.8°) in the OA group. Of patients with a CSA > 35°, 84% were in the RCT group and of those with a CSA < 30°, 93% were in the OA group. We therefore concluded that primary glenohumeral OA is associated with significantly smaller degenerative RCTs with significantly larger CSAs than asymptomatic shoulders without these pathologies. These findings suggest that individual quantitative anatomy may imply biomechanics that are likely to induce specific types of degenerative joint disorders.

Deflection and inclination measuring system for floating dock based on wireless networks

When going in or out of a dock, the self weight of the ship may cause the deflection of the pontoon deck and/or inclination of a floating dock. This paper investigates the measurements of the deflection and inclination of a floating dock within a wireless network. A deflection measurement model is constructed on the basis of the multi-points liquid levels in the connected pipes. The water levels at different points are measured by the pressure transmitters connected to the connection pipes along the longitudinal direction of the floating dock. The inclination is measured by 4 pneumercators installed on 4 corners of the floating dock. The measured data are transmitted to a server with a wireless sensor network. With the proposed model, the deflection and inclination calculation methods are analyzed and presented. The experimental results show that the accuracy of the deflection (hog or sag) can reach 95% and the error for the inclination measurement (heel or trim angle) is less than 8%. It is verified that the measuring system in the wireless sensor network supports the proposed deflection model and data collision avoiding algorithm. The measuring system could provide the required information during the operation of the floating dock.

Design of Tilt Angle Measurement System

For the purpose of inclination measurement and monitoring, a tilt angle measurement system using a heat convection accelerometer is presented in this study. A conditioning circuit that center around the single chip processor is designed and built. Experiments were carried out to characterize the measuring system with the range of-90° to +90°. The output results show nonlinear relationship. The calibration result indicates that the sensitivity of the accelerometer is about 650mV/g. The maximum error is 5.5% while the repeatability error is 3%. Experiments proved that the developed measurement system is capable of measuring tilt angle.

Correlation between sagittal dental classes and sagittal condylar inclination

Background The purpose of this work was to examine if there is any correlation between the measurements of articular eminence inclination, namely sagittal condylar inclination with the different classification of dental classes.

Influence of Morphometry and Airway Patency on Response to Inhaled Methacholine

For some individuals, the degree of response to inhaled allergens or the efficacy of inhaled pharmaceuticals may be influenced by their lung morphometry. Fourteen healthy, nonsmoking subjects received a high-resolution computed tomography (HRCT) scan just prior to performance of a methacholine challenge. Following the methacholine challenge, subjects were given a bronchodilator and received a second HRCT scan. HRCT scans were reconstructed and measurements of airway length, diameter, branch angle, and inclination to gravity were made for the first six tracheobronchial airway generations. The average length (L) and diameter (d) of each airway generation were used to calculate the average airway generation circumference (πd) and surface area (πLd). The product of airway circumference and surface area was incorporated into an airway volume factor (Ld2 ), inversely proportional to the fractional decrease in airway circumference due to deposited methacholine. Ld2 was used to compare methacholine challenge resp...

Manual and computerized measurement of coronal vertebral inclination on MRI images: A pilot study

A pilot study that presents a systematic approach for evaluating the variability of manual and computerized measurements of coronal vertebral inclination (CVI) on images acquired by magnetic resonance imaging (MRI). Three observers identified the vertebral body corners of 28 vertebrae on two occasions on two-dimensional (2D) coronal MRI cross-sections, which served to evaluate CVI using six manual measurements (superior and inferior tangents, left and right tangents, mid-endplate and mid-wall lines). Computerized measurements were performed by evaluating CVI from the symmetry of vertebral anatomical structures of the same 28 vertebrae in 2D coronal MRI cross-sections and in three-dimensional (3D) MRI images. In terms of standard deviation (SD), the mid-endplate lines proved to be the manual measurements with the lowest intra- (1.0° SD) and interobserver (1.4° SD) variability. The computerized measurements in 3D yielded even lower intra- (0.8° SD) and interobserver (1.3° SD) variability. The strongest inter-method agreement (1.2° SD) was found among lines parallel to vertebral endplates (superior tangents, inferior tangents, mid-endplate lines). The computerized measurements in 3D were most in agreement with the mid-endplate lines (1.9° SD). The estimated intra- and interobserver variabilities of standard Cobb angle measurements were equal to 1.6° SD and 2.5° SD, respectively, for manual measurements, and to 1.1° SD and 1.8° SD, respectively, for computerized measurements. The mid-endplate lines proved to be the most reproducible and reliable manual CVI measurements. Computerized CVI measurements based on the evaluation of the symmetry of vertebral anatomical structures in 3D were more reproducible and reliable than manual measurements.

THE PHOTOMETRIC AND KINEMATIC STRUCTURE OF FACE-ON DISK GALAXIES. III. KINEMATIC INCLINATIONS FROM Hα VELOCITY FIELDS

Using the integral field unit DensePak on the WIYN 3.5 m telescope we have obtained Hα velocity fields of 39 nearly face-on disks at echelle resolutions. High-quality, uniform kinematic data and a new modeling technique enabled us to derive accurate and precise kinematic inclinations with mean i kin = 23° for 90% of these galaxies. Modeling the kinematic data as single, inclined disks in circular rotation improves upon the traditional tilted-ring method. We measure kinematic inclinations with a precision in sin i of 25% at 20° and 6% at 30°. Kinematic inclinations are consistent with photometric and inverse Tully-Fisher inclinations when the sample is culled of galaxies with kinematic asymmetries, for which we give two specific prescriptions. Kinematic inclinations can therefore be used in statistical face-on Tully-Fisher studies. A weighted combination of multiple, independent inclination measurements yield the most precise and accurate inclination. Combining inverse Tully-Fisher inclinations with kinematic inclinations yields joint probability inclinations with a precision in sin i of 10% at 15° and 5% at 30°. This level of precision makes accurate mass decompositions of galaxies possible even at low inclination. We find scaling relations between rotation speed and disk-scale length identical to results from more inclined samples. We also observe the trend of more steeply rising rotation curves with increased rotation speed and light concentration. This trend appears to be uncorrelated with disk surface brightness.