scholarly journals Loading Criteria and Deposit Layer Characteristics as Causes of Sediment Settlement in an Estuary

2021 ◽  
Vol 10 (1) ◽  
pp. 27
Author(s):  
Andi Patriadi ◽  
Ria Asih Aryani Soemitro ◽  
Dwa Desa Warnana ◽  
Wasis Wardoyo ◽  
Toshifumi Mukunoki ◽  
...  
Keyword(s):  
Maximum Load ◽  
Dynamic Loads ◽  
Maximum Pressure ◽  
Sediment Layer ◽  
Load Prediction ◽  
Load Pressure ◽  
Sediment Compaction ◽  
Head Pressure ◽  
Pressure Changes ◽  
Deposit Layer

Sediment compaction due to the extraction of groundwater and self-weight consolidation, and monitoring land settlement of the river delta using geodetic measurement has been executed in several studies, while sediment settlement in the estuary is hypothesized due to dynamic loads. The present study aimed to observe clues for the occurrence of sediment settlement due to loading variation and deposit layer characteristics in the estuary. This research was based on four loading data for examination, i.e., hydraulic head pressure, sediment transport rate, sediment deposition, and water density. Two years of previous research simulations, including the rainy and dry seasons, were recalculated to gain the load pressure and were considered to assess the maximum load prediction. This review found evidence that dynamic loads predominated in maximum pressure changes in boreholes (BH2) and (BH3), and were due to river discharge and tidal occurrence, respectively. The dynamic load of sediment in BH2 contributed more than in BH3, where it was almost nonexistent. Observing the sediment layer characteristics, both settled for almost a month and two weeks, respectively, showed sediment settlement of more or less than 2 and 8 mm. Despite insignificant loading changes, these findings can further our understanding of loading criteria and settlement in different geometric locations.

scholarly journals Induction of Changes in Internal Gas Pressure of Bulky Plant Organs by Temperature Gradients

1990 ◽  
Vol 115 (2) ◽  
pp. 308-312 ◽  
Author(s):  
Kenneth A. Corey ◽  
Zhi-Yi Tan
Keyword(s):  
Bath Temperature ◽  
Ideal Gas ◽  
Gas Pressure ◽  
Temperature Gradients ◽  
Maximum Pressure ◽  
Plant Organs ◽  
Ideal Gas Law ◽  
Increasing Temperature ◽  
Pressure Changes

Water manometers were connected to fruits of tomato (Lycopersicon esculentum Mill.) and pepper (Capsicum annuum L.), and then fruits were submerged in water baths providing initial temperature gradients between fruit and water of 0 to 19C. Apple (Malus domestics Borkh.) fruits, carrot (Daucus carota L.) roots, witloof chicory (Cichorium intybus L.) roots, rhubarb Rheum rhabarbarum L.) petioles, and pokeweed (Phytolacca americana L.) stems were subjected to water bath temperature gradients of 5C. Internal partial vacuums developed in all organs within minutes of imposing the gradients. The maximum partial vacuums in tomato and pepper fruits increased with increasing temperature gradients. Uptake of water accompanied changes in internal pressure reaching maxima of 17% (w/w) and 2% (w/w) of pepper and tomato fruits, respectively, after 22 hours. Maximum pressure changes achieved in bulky organs deviated from those predicted by the ideal gas law, possibly due to concomitant changes in gas pressure upon replacement of intercellular spaces with water and dissolution of CO2. Partial vacuums also developed in pepper fruits, rhubarb petioles, and pokeweed stems following exposure to air 15C cooler than initial organ temperatures. Results point to the role of temperature gradients in the transport of liquids and gases in plant organs.

Subcutaneous tissue gas space pressure during superficial isobaric counterdiffusion

1979 ◽  
Vol 47 (1) ◽  
pp. 224-227 ◽  
Author(s):  
J. R. Cowley ◽  
C. Allegra ◽  
C. J. Lambertsen
Keyword(s):  
Gas Phase ◽  
Subcutaneous Tissue ◽  
Inert Gas ◽  
Maximum Pressure ◽  
Tissue Pressure ◽  
Phase Development ◽  
New Zealand White Rabbits ◽  
Gas Space ◽  
Pressure Changes ◽  
Mean Time

Changes in subcutaneous tissue pressure caused by N2O-He, 1-ATA isobaric counterdiffusion gas phase development were measured. Only the ears of New Zealand White rabbits were subjected to counterdiffusion. The rabbits breathed a mixture of 80% N2O-20% O2 while their ears alone were surrounded by He and the rest of their bodies continued to be surrounded by air. Subcutaneous pressure changes were transmitted to the transducer-recorded system via a fluid-filled subcutaneous needle. When the gas phase developed in subcutaneous tissue, pressure rose and a maximum pressure (Pmax) was reached. Pmax in the counterdiffused ear was 48 +/- 10 (SD) Torr, and mean time to reach Pmax was 75 +/- 10 (SD) min. The findings are discussed in relation to the pathological processes of isobaric inert gas counterdiffusion.

Paper 8: An Investigation into the Performance of Dynamically Loaded Journal Bearings: Design Study

1966 ◽  
Vol 181 (2) ◽  
pp. 28-34 ◽  
Author(s):  
T. Lloyd ◽  
R. Horsnell ◽  
H. McCallion
Keyword(s):  
Maximum Load ◽  
Design Parameters ◽  
Maximum Pressure ◽  
Inlet Temperature ◽  
Connecting Rod ◽  
Main Bearing ◽  
Bulk Oil ◽  
Engine Design ◽  
Dynamically Loaded ◽  
Bearing Loads

The objects of this paper are to demonstrate the use of the method described in Paper 6 and to give an indication of the effect of design parameters on the performance of a dynamically loaded bearing. An investigation into the main and big-end bearings of a diesel engine of modern design is described. The performance of a bearing is gauged by obtaining: (a) the minimum oil film thickness, (6) the maximum pressure developed within the oil, (c) the maximum load/projected area, and ( d) the bulk oil temperature rise. The influence of the engine design upon the big-end bearing performance for the particular engine under consideration is found by investigating the effects of the following parameters: ( a) bearing length-diameter ratio, (6) removal of centre-circumferential groove, ( c) inlet temperature, ( d) bearing clearance, and ( e) loading diagram. This last parameter is varied by changing in turn the piston mass, the connecting-rod mass, and the position of the connecting-rod centre of gravity. Finally, the effect upon the main bearing performance of various balance weight configurations is demonstrated. The usual assumption is made to obtain the main bearing loads: that loads imposed by a crank throw are equally distributed between neighbouring main bearings. General conclusions are made regarding the relative influence of certain bearing-design parameters upon the bearing performance.

scholarly journals Mechanical testing of paraosseous clamp-cerclage stabilization compared to interfragmentary wiring and combination technique in L-shape acrylic plate simulate to canine mandibular fracture

2021 ◽  
Vol 20 (1) ◽  
pp. 107-116
Author(s):  
Chaiyakorn Thitiyanaporn ◽  
◽  
Ketkaew Wasanasuk ◽  
Nessara Shomwiwat ◽  
Prapaiporn Plangngan ◽  
...  
Keyword(s):  
Lower Cost ◽  
Testing Machine ◽  
Maximum Load ◽  
Mandibular Fracture ◽  
Maximum Pressure ◽  
Combination Technique ◽  
Factors Associated ◽  
Acrylic Plate ◽  
Fixation Techniques ◽  
Stabilization Technique

The purpose of this research was to comparison of the mechanical strength of the three different stabilization techniques in canine mandibular models. An L-shaped acrylic plate to replicate the mandible of a middle-sized dog was used as a canine mandibular fracture model. The research compared the strength of 3 fixation techniques: interfragmentary wiring, paraosseous clamp-cerclage stabilization, and a combination of both techniques. Each method was tested using 6 acrylic samples and measuring the maximum pressure load on the rostral mandible model using a Hounsfield H50KS testing machine. Statistical analysis was used to summarize the maximum load results from each method. The strengths of the interfragmentary wiring technique and the combination technique were not significantly different, while the paraosseous clamp-cerclage stabilization technique had significantly less strength than the other two techniques. The acrylic samples simulated the mandibular bone in a medium-sized breed dog because there are variable sizes and conformations of the mandible. This method was used to help neutralize other confounding factors associated with using real bone. In conclusion, the combination technique of interfragmentary wiring and paraosseous clamp-cerclage was the best method that can be used for increased stabilization of mandibular fixation. This technique was useful for facilitating stabilization of a mandible at a lower cost compared with the bone plate and screw method.

Pressure distribution between the deep digital flexor tendon and the navicular bone, and the effect of raising the heels in vitro

2009 ◽  
Vol 22 (04) ◽  
pp. 278-282 ◽  
Author(s):  
D.J. Shaw ◽  
G. Munaiwa ◽  
D.P. FitzPatrick ◽  
C.R. Bellenger ◽  
M.P. Weaver
Keyword(s):  
Pressure Distribution ◽  
Flexor Tendon ◽  
Wedge Angle ◽  
Maximum Pressure ◽  
Navicular Bone ◽  
Palmar Surface ◽  
Distal Edge ◽  
Central Ridge ◽  
Pressure Changes

SummaryThe objectives of this study were to topo-graphically map pressure distribution across the palmar surface of the navicular bone in response to forces applied by the deep digital flexor tendon (DDFT), and evaluate the effect of raising the heels in vitro. A rig was constructed to hold an equine cadaver limb and apply controlled pressure to the navicular bone from the DDFT. Pressure-sensitive paper was used to quantify and map the resultant pressure. Changes in response to heel wedges (5° and 10°) were recorded. The areas subject to maximum pressure from the DDFT were: the central ridge, the paired symmetrical areas adjacent to the ridge and the distal edge of the palmar bone surface. These regions correspond to the known sites of navicular pathology. Heel wedges redistributed the pressure exerted on the palmar surface of the navicular bone, with measurements varying depending on fetlock angle and wedge angle. These in vitro results support the hypothesis that inappropriate forces exerted via the DDFT on the bone cause navicular disease. However, they throw doubt on the practice of shoeing such horses with heel wedges as the redistribution of pressure may increase the force exerted on regions predisposed to disease.

scholarly journals Postinsertional Cable Movements of Cochlear Implant Electrodes and Their Effects on Intracochlear Pressure

2016 ◽  
Vol 2016 ◽  
pp. 1-5 ◽  
Author(s):  
I. Todt ◽  
D. Karimi ◽  
J. Luger ◽  
A. Ernst ◽  
P. Mittmann
Keyword(s):  
Cochlear Implantation ◽  
Maximum Amplitude ◽  
Storage Conditions ◽  
Mastoid Cavity ◽  
Maximum Pressure ◽  
Apical Region ◽  
Pressure Amplitude ◽  
Lower Maximum ◽  
Intracochlear Pressure ◽  
Pressure Changes

Introduction.To achieve a functional atraumatic cochlear implantation, intracochlear pressure changes during the procedure should be minimized. Postinsertional cable movements are assumed to induce intracochlear pressure changes. The aim of this study was to observe intracochlear pressure changes due to postinsertional cable movements.Materials and Methods.Intracochlear pressure changes were recorded in a cochlear model with a micro-pressure sensor positioned in the apical region of the cochlea model to follow the maximum amplitude and pressure gain velocity in intracochlear pressure. A temporal bone mastoid cavity was attached to the model to simulate cable positioning. The compared conditions were (1) touching the unsealed electrode, (2) touching the sealed electrode, (3) cable storage with an unfixed cable, and (4) cable storage with a fixed cable.Results.We found statistically significant differences in the occurrence of maximum amplitude and pressure gain velocity in intracochlear pressure changes under the compared conditions. Comparing the cable storage conditions, a cable fixed mode offers significantly lower maximum pressure amplitude and pressure gain velocity than the nonfixed mode.Conclusion.Postinsertional cable movement led to a significant pressure transfer into the cochlea. Before positioning the electrode cable in the mastoid cavity, fixation of the cable is recommended.

scholarly journals Dynamic load simulation of the machine nodes containing interacting rollers

2021 ◽  
Vol 7 (2) ◽  
pp. 153-159
Author(s):  
D.I. Perminova ◽  
Keyword(s):  
Contact Problem ◽  
Dynamic Model ◽  
Dynamic Load ◽  
Dynamic Loads ◽  
Interaction Forces ◽  
Direct Modeling ◽  
Pressure Changes ◽  
Load Simulation

The article presents a dynamic model of interaction of rollers on the example of printing cylinders of an offset machine. Based on the solution of the contact problem, the interaction forces of the cylinders are determined, direct modeling of dynamic loads and vibrations is carried out, the amplitudes of vibrations and pressure changes are determined. Options for reducing loads are considered. The disadvantages of existing models of printing machines are analyzed and taken into account.

Thermal EHL of Rough Rolling/Sliding Line Contacts Using a Mixture of Two Fluids at Dynamic Loads

2002 ◽  
Vol 124 (4) ◽  
pp. 709-715 ◽  
Author(s):  
Punit Kumar ◽  
S. C. Jain ◽  
S. Ray
Keyword(s):  
Surface Roughness ◽  
Film Thickness ◽  
Dynamic Loading ◽  
Coefficient Of Friction ◽  
Contact Region ◽  
Dynamic Loads ◽  
Maximum Pressure ◽  
Moving Surface ◽  
Line Contacts ◽  
Rough Rolling

The behavior of the thermal elastohydrodynamic lubrication film in rough rolling/sliding line contacts at dynamic loads is investigated numerically. The lubricant is assumed to be a mixture of Newtonian and Ree-Eyring fluids. The results show that the maximum pressure in the contact region undergoes a noteworthy change with time due to dynamic loading and the effect of moving surface roughness. The variation of minimum film thickness and coefficient of friction with the composition of the lubricant is found to be dependent upon the reference viscosity ratio. The superposition of the effects of moving surface roughness and dynamic loading is shown to determine the behavior of time dependent film thickness and coefficient of friction.

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