Physical and Numerical Modelling of Installation and Pull-Out of Dynamically Penetrating Anchors in Clay and Silt

2013 ◽  
Author(s):  
Muhammad Shazzad Hossain ◽  
Youngho Kim ◽  
Dong Wang
Keyword(s):  
Cost Effective ◽  
Soil Strength ◽  
Terminal Velocity ◽  
Drop Height ◽  
Soil Movement ◽  
Pull Out ◽  
Flow Mechanisms ◽  
Anchoring System ◽  
Cost Effective Alternative ◽  
Soil Flow

Dynamically penetrating anchors (DPAs) are a recent type of mooring technology that have been shown to provide a cost-effective alternative to other forms of anchoring system in deep waters. This paper reports the results from a series of model tests undertaken to provide insight into the behavior of DPAs during dynamic installation and monotonic pull-out in normally consolidated clay and calcareous silt. The tests were carried out in a drum centrifuge at 200 g, varying the drop height and hence the terminal velocity. The pull-out angle at the mudline was also varied to encompass various mooring systems. This paper also reports the results from finite element (FE) analyses simulating dynamic installation of anchors. The 3D large deformation FE (LDFE) analyses were carried out using the Coupled Eulerian-Lagrangian (CEL) approach in the commercial FE package Abaqus/Explicit. A parametric study was undertaken, exploring a range of anchor geometry in terms of diameter, tip angle and number and length of fins; impact velocity and soil strength. For dynamic installation, two interesting aspects of the soil flow mechanisms were identified: (a) downward soil movement, concentrating around the advancing anchor, being reduced gradually with reducing penetration velocity and more rapidly with increasing number of fins and anchor projected area; (b) mobilisation of end bearing mechanism at the base of the anchor as well as fins, with the latter reduced significantly for shorter fins. The depth of anchor penetration increased as the drop height (and terminal velocity) increases and the soil strength decreases. For static pull-out, the mooring angle at the mudline influenced the pull-out mechanism and the capacity significantly. The anchor rotation and hence the anchor displacement required for attaining maximum capacity reduced as the angle increases.

scholarly journals MODELLING AND PREDICTION OF PRECIPITATION AND SOIL MOVEMENT BASED ON ADINSAR

2020 ◽  
Vol V-3-2020 ◽  
pp. 179-184
Author(s):  
C. H. Yang ◽  
A. Müterthies
Keyword(s):  
Cost Effective ◽  
Large Area ◽  
Hydrologic Models ◽  
New Approach ◽  
Soil Movement ◽  
Drainage Rate ◽  
Weather Observations ◽  
Cost Effective Alternative ◽  
Areas Of Interest

Abstract. Evaluating soil movement related to precipitation is needed for geologic and hydrologic applications. In principle, the soil body swells and shrinks depending on soil type, precipitation rate, moisture content, and drainage rate. The precipitations are normally measured at weather stations. Measuring the soil movement by using ground-based sensors and hydrologic models across a large area is costly and time-consuming. Also the weather observations were not fully involved in modelling. A long-term monitoring using remote sensing is a cost-effective alternative. For this purpose, we developed a new approach in this study to model the transformation between precipitation and soil movement. The time-series soil movement over a large area is evaluated by ADInSAR at mm/yr level. As a result, the predictive model can compute the precipitation at a location from its ADInSAR-derived movement, and vice versa. Our test using Sentinel-1 images shows that the prediction accuracy for precipitation is 14 mm (mean error rate 12%) and it amounts 12 mm/yr for soil movement. The accuracies indicate that our modelling is relevant to the reality. We also discuss the influences of different parameters on the modelling. In the future, we will proceed with tests considering other areas of interest, time spans, and image sources. More target points will be analysed in detail. Last but not least, we will work on the applications related to geology and hydrology.

2D Color-Intensity Representation of Ultrasonic Thickness Gauge Measurements

2020 ◽  
pp. 1192-1198
Author(s):  
M.S. Mohammad ◽  
Tibebe Tesfaye ◽  
Kim Ki-Seong
Keyword(s):  
Cost Effective ◽  
The Other ◽  
Thickness Gauge ◽  
Color Intensity ◽  
Digital Readout ◽  
Flat Surfaces ◽  
Video Cameras ◽  
Wide Range ◽  
Cost Effective Alternative ◽  
Ultrasonic Thickness

Ultrasonic thickness gauges are easy to operate and reliable, and can be used to measure a wide range of thicknesses and inspect all engineering materials. Supplementing the simple ultrasonic thickness gauges that present results in either a digital readout or as an A-scan with systems that enable correlating the measured values to their positions on the inspected surface to produce a two-dimensional (2D) thickness representation can extend their benefits and provide a cost-effective alternative to expensive advanced C-scan machines. In previous work, the authors introduced a system for the positioning and mapping of the values measured by the ultrasonic thickness gauges and flaw detectors (Tesfaye et al. 2019). The system is an alternative to the systems that use mechanical scanners, encoders, and sophisticated UT machines. It used a camera to record the probe’s movement and a projected laser grid obtained by a laser pattern generator to locate the probe on the inspected surface. In this paper, a novel system is proposed to be applied to flat surfaces, in addition to overcoming the other limitations posed due to the use of the laser projection. The proposed system uses two video cameras, one to monitor the probe’s movement on the inspected surface and the other to capture the corresponding digital readout of the thickness gauge. The acquired images of the probe’s position and thickness gauge readout are processed to plot the measured data in a 2D color-coded map. The system is meant to be simpler and more effective than the previous development.

JS777

Alloy Digest ◽  
1980 ◽  
Vol 29 (11) ◽  
Keyword(s):  
Stainless Steel ◽  
Corrosion Resistance ◽  
Austenitic Stainless Steel ◽  
Cost Effective ◽  
Heat Treating ◽  
Steel Company ◽  
High Alloy ◽  
Cost Effective Alternative ◽  
Resistance To Stress ◽  
Nickel Base

Abstract JS777 is a high-alloy, fully austenitic stainless steel developed for applications where corrosive conditions are too severe for the standard grades of stainless steel. It also provides a cost-effective alternative to more expensive nickel-base and titanium-base alloys. It has relatively high resistance to stress-corrosion cracking and to intergranular corrosion. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: SS-377. Producer or source: Jessop Steel Company.

ANCORSTEEL 4300

Alloy Digest ◽  
2009 ◽  
Vol 58 (11) ◽  
Keyword(s):  
Fracture Toughness ◽  
Physical Properties ◽  
Tensile Properties ◽  
Cost Effective ◽  
Heat Treating ◽  
Effective Alternative ◽  
Powder Metal ◽  
Secondary Processing ◽  
Cost Effective Alternative

Abstract Ancorsteel 4300 alloy ferrous powder simulates wrought steel compositions and is a cost-effective alternative to alloys requiring secondary processing. This datasheet provides information on composition, physical properties, hardness, and tensile properties as well as fracture toughness. It also includes information on heat treating and powder metal forms. Filing Code: SA-611. Producer or source: Hoeganaes Corporation.

scholarly journals OP0198-HPR A STRUCTURED MODEL FOR OA CARE IN PRIMARY HEALTHCARE IS A COST-EFFECTIVE ALTERNATIVE COMPARED TO USUAL CARE FOR PEOPLE WITH HIP AND KNEE OA

2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 119-120
Author(s):  
N. Østerås ◽  
E. Aas ◽  
T. Moseng ◽  
L. Van Bodegom-Vos ◽  
K. Dziedzic ◽  
...  
Keyword(s):  
Usual Care ◽  
Primary Healthcare ◽  
Intervention Group ◽  
Cost Effective ◽  
Cost Utility ◽  
Control Group ◽  
Structured Model ◽  
Knee Oa ◽  
Cost Effective Alternative ◽  
The Cost

Background:To improve quality of care for patients with hip and knee osteoarthritis (OA), a structured model for integrated OA care was developed based on international treatment recommendations. A previous analysis of a cluster RCT (cRCT) showed that compared to usual care, the intervention group reported higher quality of care and greater satisfaction with care. Also, more patients were treated according to international guidelines and fulfilled recommendations for physical activity at the 6-month follow-up.Objectives:To assess the cost-utility of a structured model for hip or knee OA care.Methods:A cRCT with stepped-wedge cohort design was conducted in 6 Norwegian municipalities (clusters) in 2015-17. The OA care model was implemented in one cluster at the time by switching from “usual care” to the structured model. The implementation of the model was facilitated by interactive workshops for general practitioners (GPs) and physiotherapists (PTs) with an update on OA treatment recommendations. The GPs explained the OA diagnosis and treatment alternatives, provided pharmacological treatment when appropriate, and suggested referral to physiotherapy. The PT-led patient OA education programme was group-based and lasted 3 hours followed by an 8–12-week individually tailored resistance exercise programme with twice weekly 1-hour supervised group sessions (5–10 patients per PT). An optional 10-hours Healthy Eating Program was available. Participants were ≥45 years with symptomatic hip or knee OA.Costs were measured from the healthcare perspective and collected from several sources. Patients self-reported visits in primary healthcare at 3, 6, 9 and 12 months. Secondary healthcare visits and joint surgery data were extracted from the Norwegian Patient Register. The health outcome, quality-adjusted life-year (QALY), was estimated based on the EQ-5D-5L scores at baseline, 3, 6, 9 and 12 months. The result of the cost-utility analysis was reported using the incremental cost-effectiveness ratio (ICER), defined as the incremental costs relative to incremental QALYs (QALYs gained). Based on Norwegian guidelines, the threshold is €27500. Sensitivity analyses were performed using bootstrapping to assess the robustness of reported results and presented in a cost-effectiveness plane (Figure 1).Results:The 393 patients’ mean age was 63 years (SD 9.6) and 74% were women. 109 patients were recruited during control periods (control group), and 284 patients were recruited during interventions periods (intervention group). Only the intervention group had a significant increase in EQ-5D-5L utility scores from baseline to 12 months follow-up (mean change 0.03; 95% CI 0.01, 0.05) with QALYs gained: 0.02 (95% CI -0.08, 0.12). The structured OA model cost approx. €301 p.p. with an additional €50 for the Healthy Eating Program. Total 12 months healthcare cost p.p. was €1281 in the intervention and €3147 in the control group, resulting in an incremental cost of -€1866 (95% CI -3147, -584) p.p. Costs related to surgical procedures had the largest impact on total healthcare costs in both groups. During the 12-months follow-up period, 5% (n=14) in the intervention compared to 12% (n=13) in the control group underwent joint surgery; resulting in a mean surgical procedure cost of €553 p.p. in the intervention as compared to €1624 p.p. in the control group. The ICER was -€93300, indicating that the OA care model resulted in QALYs gained and cost-savings. At a threshold of €27500, it is 99% likely that the OA care model is a cost-effective alternative.Conclusion:The results of the cost-utility analysis show that implementing a structured model for OA care in primary healthcare based on international guidelines is highly likely a cost-effective alternative compared to usual care for people with hip and knee OA. More studies are needed to confirm this finding, but this study results indicate that implementing structured OA care models in primary healthcare may be beneficial for the individual as well as for the society.Disclosure of Interests:None declared

scholarly journals Optical spin-symmetry breaking for high-efficiency directional helicity-multiplexed metaholograms

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Muhammad Ashar Naveed ◽  
Muhammad Afnan Ansari ◽  
Inki Kim ◽  
Trevon Badloe ◽  
Joohoon Kim ◽  
...  
Keyword(s):  
High Efficiency ◽  
Spin Symmetry ◽  
Cost Effective ◽  
Dielectric Materials ◽  
Additional Degree ◽  
Cost Effective Alternative ◽  
Spin Orbit Interactions ◽  
Smart Mobile ◽  
The Cost ◽  
Hydrogenated Amorphous

AbstractHelicity-multiplexed metasurfaces based on symmetric spin–orbit interactions (SOIs) have practical limits because they cannot provide central-symmetric holographic imaging. Asymmetric SOIs can effectively address such limitations, with several exciting applications in various fields ranging from asymmetric data inscription in communications to dual side displays in smart mobile devices. Low-loss dielectric materials provide an excellent platform for realizing such exotic phenomena efficiently. In this paper, we demonstrate an asymmetric SOI-dependent transmission-type metasurface in the visible domain using hydrogenated amorphous silicon (a-Si:H) nanoresonators. The proposed design approach is equipped with an additional degree of freedom in designing bi-directional helicity-multiplexed metasurfaces by breaking the conventional limit imposed by the symmetric SOI in half employment of metasurfaces for one circular handedness. Two on-axis, distinct wavefronts are produced with high transmission efficiencies, demonstrating the concept of asymmetric wavefront generation in two antiparallel directions. Additionally, the CMOS compatibility of a-Si:H makes it a cost-effective alternative to gallium nitride (GaN) and titanium dioxide (TiO2) for visible light. The cost-effective fabrication and simplicity of the proposed design technique provide an excellent candidate for high-efficiency, multifunctional, and chip-integrated demonstration of various phenomena.

scholarly journals Robotic hepatectomy is a safe and cost-effective alternative to conventional open hepatectomy: A single center experience

HPB ◽  
2020 ◽  
Vol 22 ◽  
pp. S186-S187
Author(s):  
J. Hawksworth ◽  
N.P. Llore ◽  
M.L. Holzner ◽  
P. Radkani ◽  
E. Mesler ◽  
...  
Keyword(s):  
Cost Effective ◽  
Effective Alternative ◽  
Single Center ◽  
Robotic Hepatectomy ◽  
Single Center Experience ◽  
Open Hepatectomy ◽  
Cost Effective Alternative

scholarly journals A two-stage amplified PZT sensor for monitoring lung and heart sounds in discharged pneumonia patients

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Hongbin Chen ◽  
Shuai Yu ◽  
Haiyang Liu ◽  
Jie Liu ◽  
Yongguang Xiao ◽  
...  
Keyword(s):  
High Sensitivity ◽  
Cost Effective ◽  
High Ratio ◽  
Heart Sounds ◽  
Two Stage ◽  
Diagnosis And Prognosis ◽  
Sensor Device ◽  
Cost Effective Alternative ◽  
A Charge ◽  
Highly Sensitive Detection

AbstractAssessment of lung and heart states is of critical importance for patients with pneumonia. In this study, we present a small-sized and ultrasensitive accelerometer for continuous monitoring of lung and heart sounds to evaluate the lung and heart states of patients. Based on two-stage amplification, which consists of an asymmetric gapped cantilever and a charge amplifier, our accelerometer exhibited an extremely high ratio of sensitivity to noise compared with conventional structures. Our sensor achieves a high sensitivity of 9.2 V/g at frequencies less than 1000 Hz, making it suitable to use to monitor weak physiological signals, including heart and lung sounds. For the first time, lung injury, heart injury, and both lung and heart injuries in discharged pneumonia patients were revealed by our sensor device. Our sound sensor also successfully tracked the recovery course of the discharged pneumonia patients. Over time, the lung and heart states of the patients gradually improved after discharge. Our observations were in good agreement with clinical reports. Compared with conventional medical instruments, our sensor device provides rapid and highly sensitive detection of lung and heart sounds, which greatly helps in the evaluation of lung and heart states of pneumonia patients. This sensor provides a cost-effective alternative approach to the diagnosis and prognosis of pneumonia and has the potential for clinical and home-use health monitoring.

A recent overview on the porphyrin-based π-extended small molecules as donors and acceptors for high-performance organic solar cells

2021 ◽  
Author(s):  
Venkatesh Piradi ◽  
Feng Yan ◽  
Xunjin Zhu ◽  
Wai-Yeung Raymond Wong
Keyword(s):  
Solar Cells ◽  
Solar Cell ◽  
Small Molecules ◽  
Organic Solar Cells ◽  
High Performance ◽  
Cost Effective ◽  
Effective Alternative ◽  
The Past ◽  
Cost Effective Alternative ◽  
Silicon Based

Organic solar cells (OSCs) have been considered as a promising cost-effective alternative to silicon-based solar cell counterparts due to their lightweight, mechanical flexibility, and easy fabrication features. Over the past...

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