scholarly journals Accuracy Analysis of the Measurement of Centre of Gravity and Moment of Inertia with a Swing

2021 ◽  
Vol 11 (12) ◽  
pp. 5345
Author(s):  
Roman Gabl ◽  
Thomas Davey ◽  
Edd Nixon ◽  
David M. Ingram
Keyword(s):  
Early Stage ◽  
High Accuracy ◽  
Moment Of Inertia ◽  
Experimental Investigations ◽  
Scaled Model ◽  
Centre Of Gravity ◽  
Building Process ◽  
Set Up ◽  
High Level ◽  
Motion Capturing

Floating devices under wave and current loads are typically designed based on numerical methods followed by a validation with experimental investigations. This allows an independent check due to the comparison of two different modelling approaches based on different assumptions. At an early stage of the project, numerical simulations are based on theoretical (ideal) values of the centre of gravity (CG) and moment of inertia (MI). The building process of a scaled model results very often in a requested simplification of certain parts, which can influence the CG and also the MI of the scaled model. Knowing those discrepancies allows us to improve the comparability of both approaches but the measurement of those values is connected with either a higher uncertainty or a high level of effort. A significant improvement of such measurements can be reached by the deployment of a specific experimental set-up. This paper presents the classification of the newly designed swing with a high accuracy inertial inclinometer, which was verified by the marker-based motion capturing system. The achieved experiences are useful for the future use of the set-up as well as similar investigations. The comparison with the theoretical values for the swing as well as an example model showed very good agreements and a high accuracy of few millimetres for the CG and an error smaller 1% for MI.

scholarly journals Improved Kinect sensor based motion capturing system for gait assessment

2017 ◽  
Author(s):  
Björn Müller ◽  
Winfried Ilg ◽  
Martin A. Giese ◽  
Nicolas Ludolph
Keyword(s):  
Gold Standard ◽  
High Accuracy ◽  
The Other ◽  
Microsoft Kinect ◽  
Kinect Sensor ◽  
Step Width ◽  
Gait Parameters ◽  
Optical Motion ◽  
Set Up ◽  
Motion Capturing

AbstractOptical motion capturing systems are expensive and require substantial dedicated space to be set up. On the other hand, they provide unsurpassed accuracy and reliability. In many situations however flexibility is required and the motion capturing system can only temporarily be placed. The Microsoft Kinect v2 sensor is comparatively cheap and with respect to gait analysis promising results have been published. We here present a motion capturing system that is easy to set up, flexible with respect to the sensor locations and delivers high accuracy in gait parameters comparable to a gold standard motion capturing system (VICON). Further, we demonstrate that sensor setups which track the person only from one-side are less accurate and should be replaced by two-sided setups. With respect to commonly analyzed gait parameters, especially step width, our system shows higher agreement with the VICON system than previous reports.

Performance Improvement of a Thermoacoustic Stirling Engine with In-Line Phase-Adjuster

2021 ◽  
pp. 1-14
Author(s):  
Isares Dhuchakallaya ◽  
Patcharin Saechan
Keyword(s):  
Acoustic Field ◽  
Acoustic Impedance ◽  
Heat Engine ◽  
Acoustic Power ◽  
Energy Conversion Efficiency ◽  
Operating Conditions ◽  
Maximum Efficiency ◽  
Experimental Investigations ◽  
Set Up ◽  
High Level

Abstract This study examined the influence of an in-line phase-adjuster on the energy conversion efficiency of thermoacoustic Stirling heat engine (TASHE). The numerical and experimental investigations were performed. An acoustic field in the system can be adjusted by the phase-adjuster. Therefore, the TASHE could maintain high-level performance at all operating conditions. The phase-adjuster or the telescopic in-line piston was set up at the tail of the resonance tube. The TASHE was modeled by DeltaEC to search the optimal configurations. Due to the variations of acoustic loads or operating conditions from the design criteria, the engine absolutely cannot maintain maximum efficiency. The proposed phase-adjuster could bring back its maximum efficiency by re-matching the acoustic impedance in the regenerator. In the experiments, the self-excited and steady-state temperatures were 480°C and 397°C. The TASHE can provide an acoustic power of up to 40 W. The thermo-to-acoustic efficiency of 12.03%, related to 22.56% of the Carnot efficiency, was achieved. There was a reasonably good agreement between the measured and simulation results. The function of the phase-adjuster in tuning the acoustic impedance was demonstrated experimentally. In the case of the TASHE operated under the off-design conditions, these scenarios would drop the system efficiency. This research can confirm that the phase-adjuster is the component applied to tune the acoustic field in the regenerator accurately with the minimum changes. It could help to improve the efficiency of such consequences.

The Emergence of Rabbinic Culture from the Perspective of Qumran

2015 ◽  
Vol 6 (2) ◽  
pp. 253-274
Author(s):  
Vered Noam
Keyword(s):  
Early Stage ◽  
Second Temple ◽  
Test Case ◽  
Literary Works ◽  
Jewish Culture ◽  
The Bible ◽  
Set Up

The rabbinic halakhic system, with its many facets and the literary works that comprise it, reflects a new Jewish culture, almost completely distinct in its halakhic content and scope from the biblical and postbiblical culture that preceded it. By examining Jewish legislation in the area of corpse impurity as a test case, the article studies the implications of Qumranic halakhah, as a way-station between the Bible and the Mishnah, for understanding how Tannaitic halakhah developed. The impression obtained from the material reviewed in the article is that the direction of the “Tannaitic revolution” was charted, its methods set up, and its principles established, at a surprisingly early stage, before the destruction of the Second Temple, and thus at the same time that the Qumran literature was created.

Onchocerciasis in Osse, Ondo State, Nigeria: Effectiveness of Motivational Strategies in Sustaining Compliance with Community Ivermectin Therapy

2002 ◽  
Vol 21 (2) ◽  
pp. 177-189
Author(s):  
O. U. Manafa ◽  
T. S. Awolola ◽  
A. N. Isamah
Keyword(s):  
Community Intervention ◽  
Intervention Group ◽  
Control Group ◽  
Group Discussions ◽  
Participant Satisfaction ◽  
Attitudes And Practices ◽  
Ondo State ◽  
Set Up ◽  
High Level ◽  
Knowledge Attitudes And Practices

A study in human Onchocerciasis was undertaken in four endemic communities in Ondo State, Nigeria. In-depth interviews were conducted on peoples' knowledge, attitudes, and practices regarding Onchocerciasis aetiology, treatment, prevention, and symptoms. These were complemented by key informant interviews and focus group discussions. Based on this information, an educational program was set up which included the training of selected villagers (motivators) and community intervention organized by these motivators. Evaluation used a control group where intervention was focused on other health problems in the area. Onchocerciasis education took place only with the intervention group. At the start of the project, peoples' knowledge about Onchocerciasis, its cause, treatment, prevention, and symptoms were varied and only a small proportion could link the bite of the blackfly to Onchocerciasis. The educational intervention achieved a high level of participant satisfaction which was expressed in continuous attendance at workshops and keeping appointments with motivators. The intervention helped to bring a significant improvement in the knowledge, attitudes, and practices (KAP) of the respondents. The knowledge of Onchocerciasis aetiology increased to 79.8 percent, 71.5 percent, and 74 percent from 48.5 percent, 48.7 percent, 34 percent, and 45 percent pre-intervention in the four study areas used. The project demonstrated that a community-based health education can be effective in Onchocerciasis control.

scholarly journals Developing a BIM-Based MUVR Treadmill System for Architectural Design Review and Collaboration

2021 ◽  
Vol 11 (15) ◽  
pp. 6881
Author(s):  
Calvin Chung Wai Keung ◽  
Jung In Kim ◽  
Qiao Min Ong
Keyword(s):  
Architectural Design ◽  
Human Locomotion ◽  
Virtual Space ◽  
Design Stage ◽  
Design Review ◽  
Team Members ◽  
Physical Constraints ◽  
Simulated Environment ◽  
Set Up ◽  
High Level

Virtual reality (VR) is quickly becoming the medium of choice for various architecture, engineering, and construction applications, such as design visualization, construction planning, and safety training. In particular, this technology offers an immersive experience to enhance the way architects review their design with team members. Traditionally, VR has used a desktop PC or workstation setup inside a room, yielding the risk of two users bump into each other while using multiuser VR (MUVR) applications. MUVR offers shared experiences that disrupt the conventional single-user VR setup, where multiple users can communicate and interact in the same virtual space, providing more realistic scenarios for architects in the design stage. However, this shared virtual environment introduces challenges regarding limited human locomotion and interactions, due to physical constraints of normal room spaces. This study thus presented a system framework that integrates MUVR applications into omnidirectional treadmills. The treadmills allow users an immersive walking experience in the simulated environment, without space constraints or hurt potentialities. A prototype was set up and tested in several scenarios by practitioners and students. The validated MUVR treadmill system aims to promote high-level immersion in architectural design review and collaboration.

Lung nodule classification using combination of CNN, second and higher order texture features

2021 ◽  
pp. 1-9
Author(s):  
Amrita Naik ◽  
Damodar Reddy Edla
Keyword(s):  
Malignant Tumors ◽  
Early Stage ◽  
Lung Nodule ◽  
Texture Features ◽  
Svm Classifier ◽  
Softmax Classifier ◽  
Spatial Features ◽  
High Level ◽  
Learning Architectures ◽  
Nodule Classification

Lung cancer is the most common cancer throughout the world and identification of malignant tumors at an early stage is needed for diagnosis and treatment of patient thus avoiding the progression to a later stage. In recent times, deep learning architectures such as CNN have shown promising results in effectively identifying malignant tumors in CT scans. In this paper, we combine the CNN features with texture features such as Haralick and Gray level run length matrix features to gather benefits of high level and spatial features extracted from the lung nodules to improve the accuracy of classification. These features are further classified using SVM classifier instead of softmax classifier in order to reduce the overfitting problem. Our model was validated on LUNA dataset and achieved an accuracy of 93.53%, sensitivity of 86.62%, the specificity of 96.55%, and positive predictive value of 94.02%.

scholarly journals Lung Cancer Screening by Low-Dose Computed Tomography: Part 2 – Key Elements for Programmatic Implementation of Lung Cancer Screening

2020 ◽  
Author(s):  
Stefan Delorme ◽  
Rudolf Kaaks
Keyword(s):  
Lung Cancer ◽  
Cancer Screening ◽  
Low Dose ◽  
Lung Cancer Screening ◽  
Cancer Registries ◽  
Computer Assisted ◽  
Management Algorithm ◽  
Epidemiologic Surveillance ◽  
Set Up ◽  
High Level

Purpose For screening with low-dose CT (LDCT) to be effective, the benefits must outweigh the potential risks. In large lung cancer screening studies, a mortality reduction of approx. 20 % has been reported, which requires several organizational elements to be achieved in practice. Materials and Methods The elements to be set up are an effective invitation strategy, uniform and quality-assured assessment criteria, and computer-assisted evaluation tools resulting in a nodule management algorithm to assign each nodule the needed workup intensity. For patients with confirmed lung cancer, immediate counseling and guideline-compliant treatment in tightly integrated regional expert centers with expert skills are required. First, pulmonology contacts as well as CT facilities should be available in the participant’s neighborhood. IT infrastructure, linkage to clinical cancer registries, quality management as well as epidemiologic surveillance are also required. Results An effective organization of screening will result in an articulated structure of both widely distributed pulmonology offices as the participants’ primary contacts and CT facilities as well as central expert facilities for supervision of screening activities, individual clarification of suspicious findings, and treatment of proven cancer. Conclusion In order to ensure that the benefits of screening more than outweigh the potential harms and that it will be accepted by the public, a tightly organized structure is needed to ensure wide availability of pulmonologists as first contacts and CT facilities with expert skills and high-level equipment concentrated in central facilities. Key Points:  Citation Format

Cost Effective Swath Bathymetry

2001 ◽  
Vol 35 (4) ◽  
pp. 33-45 ◽  
Author(s):  
Peter Hogarth
Keyword(s):  
Processing Time ◽  
Cost Effective ◽  
High Accuracy ◽  
High Coverage ◽  
Swath Bathymetry ◽  
World Survey ◽  
Set Up ◽  
Very High ◽  
Harbor Area ◽  
Wide Swath

Between 23rd and 25th July 2001 GeoSwath, a high specification shallow water wide swath bathymetry system, was used to survey the entire Portsmouth NH Harbor area. This paper deals with the results of this survey, illustrating the potential for significant reductions in the high costs, which have prevented widespread proliferation of Swath Bathymetry systems to date. Data, including a complete DTM gridded to 1 m resolution, will be presented and discussed in detail. These results show that the system is very easy to set up and use, requires greatly reduced boat and processing time, whilst offering high accuracy and very high coverage and resolution when used in a real-world survey of a dynamic harbor environment.

Leakage Flow Investigations on a Through-Wall Crack Related to Thermal Fatigue of Nuclear Power Plant Piping

2017 ◽  
Author(s):  
Stefan Schmid ◽  
Rudi Kulenovic ◽  
Eckart Laurien
Keyword(s):  
Experimental Data ◽  
Nuclear Power ◽  
Numerical Models ◽  
Measurement Techniques ◽  
Experimental Investigations ◽  
Leakage Flow ◽  
Test Rig ◽  
Reduced Pressure ◽  
Flow Rates ◽  
Set Up

For the validation of empirical models to calculate leakage flow rates in through-wall cracks of piping, reliable experimental data are essential. In this context, the Leakage Flow (LF) test rig was built up at the IKE for measurements of leakage flow rates with reduced pressure (maximum 1 MPA) and temperature (maximum 170 °C) compared to real plant conditions. The design of the test rig enables experimental investigations of through-wall cracks with different geometries and orientations by means of circular blank sheets with integrated cracks which are installed in the tubular test section of the test rig. In the paper, the experimental LF set-up and used measurement techniques are explained in detail. Furthermore, first leakage flow measurement results for one through-wall crack geometry and different imposed fluid pressures at ambient temperature conditions are presented and discussed. As an additional aspect the experimental data are used for the determination of the flow resistance of the investigated leak channel. Finally, the experimental results are compared with numerical results of WinLeck calculations to prove specifically in WinLeck implemented numerical models.

scholarly journals Assessment of the Deterioration State of Post-Installed Bonded Anchors Using Ultrasonic

Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2077
Author(s):  
Oliver Zeman ◽  
Michael Schwenn ◽  
Martin Granig ◽  
Konrad Bergmeister
Keyword(s):  
Maximum Load ◽  
Assessment Method ◽  
Load Level ◽  
Experimental Investigations ◽  
Load History ◽  
Anchor System ◽  
Ultrasonic Methods ◽  
Building Maintenance ◽  
History Of ◽  
Set Up

The assessment of already installed anchorages for a possible exceeding of the service load level is a question that is gaining more and more importance, especially in building maintenance. Bonded anchors are of particular interest here, as the detection of a capacity reduction or load exceedance can cause damage to the concrete-bonded mortar behavior. This article investigates the extent to which ultrasonic methods can be used to make a prediction about the condition of anchorages in concrete and about their load history. A promising innovative assessment method has been developed. The challenges in carrying out the experimental investigations are the arrangement of the transducers, the design of the test set-up and the applicability of direct, indirect or semidirect ultrasonic transmission. The experimental investigations carried out on a test concrete mix and a bonded anchor system show that damage to the concrete structure can be detected by means of ultrasound. The results indicate the formation of cracks and therefore a weakening of the response determined by means of direct, indirect and semidirect ultrasonic transmission. However, for application under non-laboratory conditions and on anchors with unknown load history, the calibration with a reference anchor and the identification of the maximum load is required. This enables a referencing of the other loaded anchors to the unloaded conditions and allows an estimation of the load history of individual anchors.

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