Water Bed Research Articles

Reservoir Turbidity Current Modeling with a Two-Dimensional Layer-Averaged Model

AbstractA two-dimensional layer-averaged model is developed and verified to simulate turbidity current characteristics and its sluicing in reservoirs. The governing equations consist of mass and momentum conservation laws for the turbidity current mixture, equations for the sediment transport and bed dynamics, and auxiliary relations for the interactions among clear water, turbidity current, and bed. A finite-volume, unstructured, polygonal mesh method is adopted so that reservoirs with complex terrains may be simulated. Special algorithms are developed to capture the turbidity current front movement through a clear water bed and to simulate turbidity current sluicing through reservoir outlets. The developed model has been tested and verified with both conservative and nonconservative turbidity currents ranging from simple to complex reservoir terrains. Case studies presented include a lock-exchange turbidity current with large eddy simulation and direct numerical simulation results, a laboratory test of ...

Dimensional Characterization of Surface Contours of Cut Surfaces with Plasma Straight Metallic Materials

The purpose of this paper is to analyze the dimensional accuracy of the surfaces straight edges from cutting plasma free atmosphere or water bed. The aim was to identify any defects and if bed piss water cut in some way influence the surface quality and dimensional contours right. Mechanical thermal plasma cutting bed prevents overheating of the water has the advantage that the base material and thus the parameters related to compliance with the slag assures cut pieces at the bottom, this saves the cost of production. Mechanized plasma cutting bed heat the water does not affect the value of angle tolerance compared to cutting outdoor (angular deviation determined either for parts or cut outdoor water bed ranged between 7-9 degrees / side). The causes of and ways to reduce the deviation angle cut edge is determined by other factors such as cutting speed, distance torch-material, cutting nozzle erosion.

Adaptive attenuation of unknown and time‐varying narrow band and broadband disturbances

SummaryIn many classes of applications like active vibration control and active noise control, the disturbances can be characterized by their frequency content and their location in a specific region in the frequency domain. The disturbances can be of narrow band type (simple or multiple) or of broad band type. A model can be associated to these disturbances. The knowledge of this model allows to design an appropriate control system in order to attenuate (or to reject) their effect upon the system to be controlled. The attenuation of disturbances by feedback is limited by the Bode Integral and the ‘water bed’ effect upon the output sensitivity function. In such situations, the feedback approach has to be complemented by a ‘feedforward disturbance compensation’ requiring an additional transducer for obtaining information upon the disturbance. Unfortunately, in most of the situations, the disturbances are unknown and time‐varying and therefore an adaptive approach should be considered. The generic term for adaptive attenuation of unknown and time‐varying disturbances is ‘adaptive regulation’ (known plant model, unknown, and time‐varying disturbance model).The paper will review a number of recent developments for adaptive feedback compensation of multiple unknown and time‐varying narrow band disturbances and for adaptive feedforward compensation of broad band disturbances in the presence of the inherent internal positive feedback caused by the coupling between the compensator system and the measurement of the image of the disturbance. Some experimental results obtained on a relevant active vibration control system will illustrate the performance of the various algorithms presented. Some open research problems will be mentioned in the conclusion. Copyright © 2015 John Wiley & Sons, Ltd.

The Effect of Particle Size on The Migration Rate of Knickpoint Erosion at Different Hydraulic Conditions

Abstract. Knickpoint, gully or head cut is called the erosion that is formed because of the sudden change in water level or bed level in the river and after concentrating the flow lines the local shear stress increase, bring about the bed erosion rate be intensified in a location where sudden change bed takes place. This erosion causes the riverbed in the location of sudden slope change to migrate to the upstream and makes the width of the river change. This erosion creates irreparable damages. Destruction of upstream structures caused by the bed migration and also roads destruction, residential areas, tourism - recreational areas, farmlands and good vegetation cover can be mentioned. In this paper, we have studied the effect of particle size and various hydraulic conditions to the rate of Knickpoint erosion progression. In this paper to create the relations of migration rate to the upstream according to the hydraulic parameters a laboratory hydraulic flume with dimensions 3 meters in length, width 30cm and height 50 cm was used. The main purpose of the paper is to creating relations for predicting the rate of Knickpoint erosion rates increase in the non-cohesive soil.

Adaptive active vibration isolation – A control perspective

In many classes of applications like active vibration control and active noise control, the disturbances can be characterized by their frequencies content and their location in a specific region in the frequency domain. The disturbances can be of narrow band type (simple or multiple) or of broad band type. A model can be associated to these disturbances. The knowledge of the disturbance model as well as of the compensator system is necessary for the design of an appropriate control system in order to attenuate (or to reject) their effect upon the system to be controlled. The attenuation of disturbances by feedback is limited by the Bode Integral and the water bed effect upon the output sensitivity function. In such situations, the feedback approach has to be complemented by a disturbance requiring an additional transducer for getting information upon the disturbance. Unfortunately in most of the situations the disturbances are unknown and time-varying and therefore an approach should be considered. The generic term for attenuation of unknown and time-varying disturbances is adaptive regulation (known plant model, unknown and time-varying disturbance model). The paper will review a number of recent developments for feedback compensation of multiple unknown and time- varying narrow band disturbances and for feedforward compensation of broad band disturbances in the presence of the inherent internal positive feedback caused by the coupling between the compensator system and the measurement of the image of the disturbance. Some experimental results obtained on a relevant active vibration control system will illustrate the performance of the various algorithms presented.

The Impact of Marking the Political Boundaries in the Extraurban Areas

Abstract The article aims to present the problems that may arise in the implementation of the cadastral works on stock of wood, works in the extraurban areas, on the political boundaries. Solutions are being looked for as regards the assigned areas that are disintegrated by the boundary between districts, without compromising the law enforcement 165/2013 on the restitution of the abusively confiscated estates. In order to compare the assigned areas with the measured ones, the data has been overlapped on the orthophotoplan. The political boundary was added. The line, generally traced on the road axis, cut the forest management that has the limit up to the mean water bed. Areas that have less than 100 sqm appeared, which according to the Regulation 700/2014 of endorsement, reception and registration in the cadastral records do not receive cadastral numbers. The reference material will thus get more cadastral numbers on different political boundaries, involving additional costs at the real estate registrationand a missing area as opposed to the documents.

LARGE SCALE EXPERIMENTS ON BEACH EVOLUTION INDUCED BY BICHROMATIC WAVE GROUPS WITH VARYING GROUP PERIOD

New large scale experimental data have been presented showing the wave group influence on beach morphodynamics at the surf and swash zones. Bichromatic wave conditions were generated varying the modulation bandwidth but keeping the wave energetic content constant within the experimentation limits. The wave group influence in the surf zone is observed in the form of the cross-shore location of the breaker bar respect to the initial still water level (SWL) location, which has been shown to increase as increases the wave group period. This influence is explained in terms of differences on the surf zone width induced by the varying wave group periods. In the swash zone, time dependent bed level elevation measurements were done using a newly developed conductivity technique, the CCM+ system. Bed level time variations at the swash zone have shown to be composed of a long scale trend and bed level oscillations of shorter frequencies related to the wave group forcing. A good spectral correlation has been found between the water surface elevation and bed level variation at the wave group period for every bichromatic component indicating an important influence of wave groups on the swash zone morphodynamics.

Low-Resolution Modeling of Dense Drainage Networks in Confining Layers.

Groundwater-surface water (GW-SW) interaction in numerical groundwater flow models is generally simulated using a Cauchy boundary condition, which relates the flow between the surface water and the groundwater to the product of the head difference between the node and the surface water level, and a coefficient, often referred to as the "conductance." Previous studies have shown that in models with a low grid resolution, the resistance to GW-SW interaction below the surface water bed should often be accounted for in the parameterization of the conductance, in addition to the resistance across the surface water bed. Three conductance expressions that take this resistance into account were investigated: two that were presented by Mehl and Hill (2010) and the one that was presented by De Lange (1999). Their accuracy in low-resolution models regarding salt and water fluxes to a dense drainage network in a confined aquifer system was determined. For a wide range of hydrogeological conditions, the influence of (1) variable groundwater density; (2) vertical grid discretization; and (3) simulation of both ditches and tile drains in a single model cell was investigated. The results indicate that the conductance expression of De Lange (1999) should be used in similar hydrogeological conditions as considered in this paper, as it is better taking into account the resistance to flow below the surface water bed. For the cases that were considered, the influence of variable groundwater density and vertical grid discretization on the accuracy of the conductance expression of De Lange (1999) is small.

Characterization of Plasma Cut Surfaces with Water Bed Welding Metallic Materials

The purpose of this paper is to analyze the quality of cut surfaces with plasma in the free atmosphere and in the water bed of metallic materials being welded. This process leads to savings in labor, materials, supplies and other costs of production, having as purpose the decrease in the cost of cutting the work piece and reducing deformation and heat affected zone in the piece cut, providing alternatives to processing cutting. It was designed and built a device cutting water bed that has been proven. In the macroscopic analysis reveals that the cutting in water bed slag layer is lower. After microhardness measurements (base material, heat affected zone, the cut) it is found that the cutting in water bed cut occurs on the surface microhardness increased by 36% .

Cost-consequence analysis of “washing without water” for nursing home residents: A cluster randomized trial

BackgroundNo-rinse disposable wash gloves are increasingly implemented in health care to replace traditional soap and water bed baths without proper evaluation of (cost) effectiveness. ObjectivesTo compare bed baths for effects on skin integrity and resistance against bathing and costs. DesignCluster randomized trial. SettingFifty six nursing home wards in the Netherlands.Participants: Five hundred adult care-dependent residents and 275 nurses from nursing home wards. MethodsThe experimental condition ‘washing without water’ consists of a bed bath with disposable wash gloves made of non-woven waffled fibers, saturated with a no-rinse, quickly vaporizing skin cleaning and caring lotion. The control condition is a traditional bed bath using soap, water, washcloths and towels. Both conditions were continued for 6 weeks.Outcome measures were prevalence of skin damage distinguished in two levels of severity: any skin abnormality/lesion and significant skin lesions. Additional outcomes: resistance during bed baths, costs. ResultsAny skin abnormalities/lesions over time decreased slightly in the experimental group, and increased slightly in the control group, resulting in 72.7% vs 77.6% of residents having any skin abnormalities/lesions after 6 weeks, respectively (p=0.04). There were no differences in significant skin lesions or resistance after 6 weeks.Mean costs for bed baths during 6 weeks per resident were estimated at €218.30 (95%CI 150.52–286.08) in the experimental group and €232.20 (95%CI: 203.80–260.60) in the control group (difference €13.90 (95%CI: −25.61–53.42). ConclusionWashing without water mildly protects from skin abnormalities/lesions, costs for preparing and performing bed baths do not differ from costs for traditional bed bathing. Thus, washing without water can be considered the more efficient alternative.

Care of the infant with neonatal abstinence syndrome: strength of the evidence.

There is little empirical evidence that guides management of infants with neonatal abstinence syndrome. The standard of care first described in the 1970s is still prevalent today, although it has never been tested in this population. Standard of care interventions include decreasing external stimulation, holding, nonnutritive sucking, swaddling, pressure/rubbing, and rocking. These interventions meet the goals of nonpharmacologic interventions, which are to facilitate parental attachment and decrease external stimuli. Many nursing interventions used in infants with neonatal abstinence syndrome have been tested in low-birth-weight infants, whose treatment often includes the same goals. Those interventions include music therapy, kangaroo care, massage, and use of nonoscillating water beds. Nursing attitude has also been shown to be impactful on parental attachment. The American Academy of Pediatrics recommends breast-feeding in infants whose mothers are on methadone who do not have any other contraindication. It also provides guidelines for pharmacologic management but cannot provide specific recommendations about a standard first dose, escalation, or weaning schedule. Buprenorphine has some evidence about its safety in newborns with neonatal abstinence syndrome, but high-powered studies on its efficacy are currently lacking. There are many opportunities for both evidence-based projects and nursing research projects in this population.

Controlled Large-Scale Tests of Practical Grounding Electrodes—Part I: Test Facility and Measurement of Site Parameters

This paper describes the establishment of a large-area outdoor experimental facility at the Dinorwig pumped-storage power station in North Wales for investigating the performance of practical grounding systems. The facility itself and arrangements of test electrodes and measurement equipment are described, providing a background for subsequent test methodologies. In addition, tests to determine the variation in the water and reservoir bed resistivities have been undertaken, resulting in a survey data set that better informs experimental work and simulations of vertical ground rod and grid electrodes. It is proposed that this facility may also be used to calibrate grounding meters and for validating computational modelling techniques. In a complementary paper, results of low-voltage dc, ac, and impulse tests of varying magnitudes are described, and experimental results are compared with computed values obtained from numerical models.

Fire Test of Profile Plank for Transformer Pit Fire Protection

In general it is recommended to fill a transformer pit with rock ballast to extinguish the fire if there is a leakage of burning transformer oil. There is a lack of technology-neutral performance requirements for the design of solutions for fire extinguishment in transformer pit fires. This hampers the introduction of alternatives to the traditional method of filling the pit with rocks. Therefore we have conducted quantitative tests where temperatures and concentrations of CO, CO2, and O2 were measured at different position in a transformer pit subjected to burning oil simulating an accidental rupture and leakage. The tests were conducted to investigate the extinguishing capacity of one specific alternative solution, i.e. a profile plank layer over the pit. Three tests were performed with 90°C and 140°C pre-heated transformer oil. In the second test, a 19 cm water bed was used to examine the impact of rain water in the pit. The result showed that the profile plank extinguished the flames in a few seconds and that the water level did not have any significant effect on the result. The measurements showed that the temperatures peaked at 600–800°C 50 cm above the profile plank in all tests but dropped to under 100°C in 14–16 s. Furthermore the O2-concentration dropped to 3–5 vol% below the plank, which contributed to the rapid extinction of the burning oil.

Specific features of coleoptera habitation in the Trans-Altai Gobi Desert, Mongolia

Water streams in the temporary water beds after heavy showers in the extra-arid Mongolian Trans-Altai Gobi Desert kill many coleopterans especially those with the larvae feeding on and in roots in the soil or in the stem/root base. Another impact of the flooding of desert habitats is the development of fungal infections in the stem- or root-mining larvae and adults. In the areas with often draughts, soil-dwelling larvae of cleonines can remain inactive in the air-dry soil for at least 1.5 years and immediately pupate after rainfall which evidently has a function of the signal for completion of premature development. In the desert landscape with low diversity and population densities of insectivorous birds, reptiles, and mammals, rodents (jerboas) may be the main predators of the root-feeding beetle larvae, digging them out of the soil or taking them off the stem base.

Sweet food improves chronic stress-induced irritable bowel syndrome-like symptoms in rats.

To investigate whether palatable sweet foods have a beneficial effect on chronic stress-induced colonic motility and inflammatory cytokines. Adult male rats were divided into 3 groups: control (CON, n = 5), chronic variable stress with chow (CVS-A, n = 6), and chronic variable stress with chow and sweet food (CVS-B, n = 6). The rats were fed standard rodent chow as the chow food and/or AIN-76A as the sweet food. A food preference test for AIN-76A was performed in another group of normal rats (n = 10) for twelve days. Fecal pellet output (FPO) was measured for 6 wk during water bedding stress in the CVS groups. The weight of the adrenal glands, adrenocorticotropic hormone (ACTH) and corticosterone levels in plasma were measured. The expression levels of transforming growth factor-β, interleukin (IL)-2, and interferon-gamma (IFN-γ) were measured in the distal part of colonic tissues and plasma using Western blot analysis. In sweet preference test, all rats initially preferred sweet food to chow food. However, the consumption rate of sweet food gradually decreased and reduced to below 50% of total intake eight days after sweet food feeding. Accumulated FPO was higher in the CVS-A group compared with the CVS-B group over time. All stress groups showed significant increases in the adrenal to body weight ratio (CVS-A, 0.14 ± 0.01; CVS-B, 0.14 ± 0.01) compared with the control group (0.12 ± 0.01, P < 0.05). The plasma corticosterone and ACTH levels were significantly higher in the CVS-A (537.42 ± 32.95, 44.44 ± 6.54 pg/mL) and CVS-B (655.07 ± 30.82, 65.46 ± 4.44 pg/mL) groups than in the control group (46.96 ± 13.29, 8.51 ± 1.35 pg/mL, P < 0.05). Notably, the ratio of corticosterone to ACTH was significantly increased in the CVS-A group only. Rats exposed to CVS displayed significantly increased expression of IL-2 and IFN-γ in the plasma and distal colon compared to the control group, whereas this effect was significantly attenuated in the CVS-B group. These results suggest that concurrent sweet food ingestion during CVS might have an effect on the reduction of stress-induced colonic hyper-motility and pro-inflammatory cytokine production in rats.

Numerical simulation of flow past an underwater energy storage balloon

A three-dimensional simulation was conducted to investigate water flow over the accumulator unit of an underwater compressed air energy storage system. The accumulator unit, which is a droplet shaped balloon, was installed close to the bed of deep water. The simulation was carried out at a free stream Reynolds number of 2.3×105 using URANS k–ω and LES Dyna-SM turbulence models. The URANS model failed to capture the turbulent nature of the flow; however, its predictions of the mean values were in reasonable agreement with those of the LES model. The time-averaged force coefficients of the balloon were found to be greater compared to the literature for spherical bluff bodies and smaller than those of circular cylinders. The structure of the flow was closely investigated using isosurfaces of the second invariant of the velocity gradient and three-dimensional path lines. Several shedding vortex tubes were identified downstream of the balloon. The dynamics of these vortex tubes was further illustrated through time series snapshots containing vorticity lines on two-dimensional planes perpendicular to the flow direction. The frequency of the shedding and the turbulent movements of the vortex tubes were studied through power spectrum analysis of the force coefficients.

Erodibility of soft freshwater sediments in Markermeer: the role of bioturbation by meiobenthic fauna

The Markermeer is a large and shallow man-made freshwater lake in the Netherlands, characterized by its high turbidity. As part of a study aiming to mitigate this high turbidity, we studied the water–bed exchange processes of the lake’s muddy bed. The upper centimeter’s–decimeter’s of the lake bed sediments mainly consists of soft anoxic mud. Recent measurements have proved the existence of a thin oxic layer on top of this soft anoxic mud. This oxic layer, which is much easier to be eroded than the anoxic mud, is believed to be related with Markermeer’s high-turbidity levels. Our hypothesis is that the thin oxic layer develops from the anoxic mud, enhanced by bioturbation. Actually, we will demonstrate that it is the bioturbated state of the bed that increases its erodability, and not the oxidation state of the sediments. In particular, we will refer to bioturbation caused by meiobenthic fauna. The objective of this study is therefore to determine the influence of the development of the thin oxic layer on the water–bed exchange processes, as well as to establish the role of bioturbation on those processes. This is done by quantifying the erosion rate as a function of bed shear stresses, and at different stages of the development of the oxic layer. Our experiments show that bioturbation increases the rate at which Markermeer sediments are eroded by almost an order of magnitude. The short-term fine sediment dynamics in Markermeer are found to be driven by the complex and highly dynamic interactions between physics, chemistry, and biology. Finally, the long-term fine sediment dynamics are driven by the erosion of the historical deposits in the lake’s bed, which is only possible after bioturbation, and which leads to an increase of the stock of sediments in the lake’s muddy bed.

Apply array induction logging to study the low-resistivity belt zone identification method

By applying high-definition induction logging (HDIL), we can precisely obtain flushed zone, transitional zone, and true formation resistivity profiles. HDIL has a distinct advantage in oil and water bed identification. However, when there is a low resistive zone in the reservoir, array induction logging is disabled to identify fluid. Two-parameter recognition was modified, which has a perfect effect in recognizing low-resistivity oil layer and low-resistivity belt zone; accuracy was 100 %. Two-parameter method supplies technological support in finding subtle oil layer and provides ideas for other array logging as well.

DERMITE DE CONTACTO ALÉRGICA AO METILCLORO- E METILISOTIAZOLINONA NUMA CAMA DE ÁGUA?

Descrevemos um caso clínico de dermite de contacto alérgica, grave e generalizada, resultante de con- tacto com a superfície de cama de água, que estava contaminada pela água do interior que tinha sido tratada pela mistura biocida de metilcloro- e metilisotiazolinona.PALAVRAS-CHAVE – Dermatite de Contacto Alérgica.

Sediment chlorophyll 'a' and nutrients characteristics of the upper bonny estuary, amadi-ama creek, port harcourt, Nigeria

The sediment chlorophyll ‘a’ and nutrient characteristics of the Amadi-Ama creek was studied for 24 months between January 2009 – December 2010.Sediments samples collected from the water bed at low tide were analysed for the variable following standard methods. The data were subjected to analysis of variance(ANOVA), Duncan Multiple range test(DMR) and pearson correlation coefficient.They all showed spatial and seasonal variations with higher values in the dry season than the wet season except Chlorophyll ‘a’, and sulphate which did not show seasonal difference for the two years. The highest values of chlorophyll ‘a’ and sulphate were observed in station 3 throughout the period of study.