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Interpretation of the Falling Weight Deflectometer (FWD) testing Data for the Nairobi Eastern By-Pass Road Flexible Pavement

Interpretation of the Falling Weight Deflectometer (FWD) testing Data for the Nairobi Eastern By-Pass Road Flexible Pavement

Falling weight Deflectometer (FWD) testing is today the common tool used to assess the structural condition of the pavement. The objective of the study was to analyse the FWD surface deflection test results of flexible pavement for the Nairobi Eastern by-pass to predict the pavement’s structural capacity. The study observed that the pavement exhibits varying characteristics from strong pavement to moderate pavement as the deflections values fluctuates along the pavement length with much of the pavement stretch being characterized as reasonably strong. Three locations at around chainages14.4km, 24.2kms and 25.8kms had signs of a moderate pavement that required a thin overlay despite the pavement structure showing characteristics of stability. It was recommended that surface dressing with 10/14 class 1 chippings and 80/100 penetration grade bitumen binder for pavement surface treatment will be suitable for the entire stretch of the study section.

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Improving the Accuracy and Usability of Iowa Falling Weight Deflectometer Data

Improving the Accuracy and Usability of Iowa Falling Weight Deflectometer Data

This study aims to improve the accuracy and usability of Iowa Falling Weight Deflectometer (FWD) data by incorporating significant enhancements into the fully-automated software system for rapid processing of the FWD data. These enhancements include: (1) refined prediction of backcalculated pavement layer modulus through deflection basin matching/optimization, (2) temperature correction of backcalculated Hot-Mix Asphalt (HMA) layer modulus, (3) computation of 1993 AASHTO design guide related effective SN (SNeff) and effective k-value (keff ), (4) computation of Iowa DOT asphalt concrete (AC) overlay design related Structural Rating (SR) and k-value (k), and (5) enhancement of user-friendliness of input and output from the software tool. A high-quality, easy-to-use backcalculation software package, referred to as, I-BACK: the Iowa Pavement Backcalculation Software, was developed to achieve the project goals and requirements. This report presents theoretical background behind the incorporated enhancements as well as guidance on the use of I-BACK developed in this study. The developed tool, I-BACK, provides more fine-tuned ANN pavement backcalculation results by implementation of deflection basin matching optimizer for conventional flexible, full-depth, rigid, and composite pavements. Implementation of this tool within Iowa DOT will facilitate accurate pavement structural evaluation and rehabilitation designs for pavement/asset management purposes. This research has also set the framework for the development of a simplified FWD deflection based HMA overlay design procedure which is one of the recommended areas for future research.

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Comparative Studies between Benkelman Beam Deflections (BBD) and Falling Weight Deflectometer (FWD) Test for Flexible Road Pavement

Comparative Studies between Benkelman Beam Deflections (BBD) and Falling Weight Deflectometer (FWD) Test for Flexible Road Pavement

Most of the road network in India has a significant level of deterioration and therefore requires major rehabilitation projects; in general, most of these rehabilitation activities involve a new asphalt layer on the original pavement structure; knowledge and analysis of structural capacity of the pavement is essential to perform a durable and economical rehabilitation design. The determination of the structural capacity of flexible pavements as a function of the deflections produced by the application of a load. The techniques most used in many countries to measure pavement deflections are the Falling Weight Deflectometer (FWD) and the Benkelman beam, the first one works under dynamic loading and the second device under static loading. The use of devices under static loading has not been recommended by several design methodologies, including AASHTO, but these are still used widely in many countries including India, for this reason it is necessary to compare the deflections by Benkelman beam and falling weight deflectmeter. In this study deflections measure by BBD and FWD techniques on 30 deflection observation points on selected 1.5 km flexible urban highway stretch. Both test are perform simultaneously on marking points. And data collected by booth test are as per IRC: 81-1997 and IRC: 115-2014.

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Possibilities of using the portable falling weight deflectometer to measure the bearing capacity and compaction of forest soils

Possibilities of using the portable falling weight deflectometer to measure the bearing capacity and compaction of forest soils

ABSTRACT: The paper discusses possibilities of using the portable falling weight deflectometer to measure the bearing capacity and compaction of forest soils. Within the study, measurements were made using manual penetrometer and Loadman II portable falling weight deflectometer. To eliminate the extreme values, Grubbs’s test was used. The results indicate that Loadman II deflectometer may be used to measure both the bearing capacity and compaction of forest soils under the canopy as well as in transport lines. A significant difference was found between deflection of water- unaffected sites and water-affected sites (12.08 and 2.31 mm, respectively). Measurements of bearing capacity after removal of forest litter give far more precise details; however, the authors do not refuse the measurements without litter removal, either. To determine the degrees of soil compaction, it is useful to measure the soil reaction time; to measure the bearing capacity it is vital to measure deflection.

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Use of Falling Weight Deflectometer Multi-Load Level Data for Pavement Strength Estimation.

Use of Falling Weight Deflectometer Multi-Load Level Data for Pavement Strength Estimation.

The deflection ratio concept was applied to the FWD deflections obtained from test sections in DataPave 2.0. The deflection ratios are plotted against the AC mid-depth temperatures in Figures 6.37 through 6.39 for pavements with gravel, crushed stone, and hot mix asphalt concrete (HMAC) base layer. It is noted that the subgrade soils in these pavement sections are silty or granular sandy materials except for the 48-1068 section. For gravel and crushed stone base pavements, the deflection ratios are less than one at a wide range of temperatures, which demonstrates the possible hardening behavior of pavement materials. Compared with Figures 6.34 and 6.36 for aggregate base pavements in NC secondary roads, this result indicates a good quality of base and subgrade materials in these sections.

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Non Destructive Evaluation of Iowa Pavements Phase 2: Development of a Fully Automated Software System for Rapid Analysis/Processing of the Falling Weight Deflectometer Data

Non Destructive Evaluation of Iowa Pavements Phase 2: Development of a Fully Automated Software System for Rapid Analysis/Processing of the Falling Weight Deflectometer Data

The Office of Special Investigations at Iowa Department of Transportation (DOT) collects FWD data on regular basis to evaluate pavement structural conditions. The primary objective of this study was to develop a fully-automated software system for rapid processing of the FWD data along with a user manual. The software system automatically reads the FWD raw data collected by the JILS-20 type FWD machine that Iowa DOT owns, processes and analyzes the collected data with the rapid prediction algorithms developed during the phase I study. This system smoothly integrates the FWD data analysis algorithms and the computer program being used to collect the pavement deflection data. This system can be used to assess pavement condition, estimate remaining pavement life, and eventually help assess pavement rehabilitation strategies by the Iowa DOT pavement management team. This report describes the developed software in detail and can also be used as a user-manual for conducting simulation studies and detailed analyses.

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Falling Weight Deflectometer Analysis of Low Volume Roads

Falling Weight Deflectometer Analysis of Low Volume Roads

The requirement for rigid pavement actual test track is constructed with Sub base as flexible crust layer and top layer with concrete and geocells to be treated as rigid pavement crust layer. Normal FWD test is to be carried out at min. 150 m. Being test constructed for research purpose to innovate various strength parameters, analysis is done with rigid and also with flexible pavement strength analysis. For this analysis three test points are located on test track and testing has been carried out for 60KN dynamic loads. In flexible analysis Pavement crust has been divided in two layers of each 2 Layers 7.5cm concrete as rigid pavement and 2 layers of 25cm of subbase as flexible pavement.

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Intelligent Road Inspection with Advanced Machine Learning; Hybrid Prediction Models for Smart Mobility and Transportation Maintenance Systems

Intelligent Road Inspection with Advanced Machine Learning; Hybrid Prediction Models for Smart Mobility and Transportation Maintenance Systems

A very common index in the PMSs is the PCI, which was developed by the US Army Corps of Engineers in 1982. PCI is an indicator of surface functional condition and structural integrity [8]. After visual inspection of the pavement network, pavement engineers calculate PCI based on distress type, severity, and quantity. This index varies from zero for a virtually unusable pavement to 100 for a perfect pavement [9]. On the other hand, the assessment of structural conditions generally performed by non-destructive tests such as Falling Weight Deflectometer (FWD) [10-13]. In the FWD test, an impulsive load applies to the pavement surface for 25-30 ms and the surface deflections are recorded by seven (or more) sensors. The sensors measurements are analyzed by back-calculation software such as ELMOD and MODULUS and useful information, including overlay thickness, layers modulus, and remaining life is determined [14-16].

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Falling mythologies

Falling mythologies

The impulse was a combination of worlds. My own one full of responsibility, the awareness and presence of death and environmental decay, the necessity of order and formality, combined with her freedom, the endless possibility of her future, and the absolute joy in the fleeting moments of childhood. My palette warmed in this work for the first time. I limited my use of blues and pushed into violets to construct her form. I wanted her to have color and life infusing it into the transitions of her face and body which thrusts out to the viewer and leads you in. She is unaware of my landscape behind her, with the static ordered trees cutting across the canvas like teeth and the blue sky which is witness to the falling of blurred birds. They are counterbalancing her happiness and innocence. It is a conversation between a future that may not contain as much possibility for her as I had and her inability to yet understand the heaviness of knowing mortality and all that death can take from us. If I could paint her world differently I would and in it I would take away the weight of losing all that we love to time.

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The application of instrumented falling weight impact test to determine the ductile-brittle transition in acrylate rubber-modified PVC

The application of instrumented falling weight impact test to determine the ductile-brittle transition in acrylate rubber-modified PVC

The study o f the effect o f filter frequency on force-deflection traces in Instrumented Falling W eight Impact (IFWI) testing is important to determine the most suitable filter frequency for all future IFW I testing work. During impact there are vibrations which interfere with the true force-deflection curve and therefore filtering o f the noise is necessary to remove part o f the curve due to the interference. The Rosand Impact Tester has a facility whereby the signal can be electronically filtered. The frequency of the filter control can be set manually at levels between 1 and 20 kHz. For example, a setting of 1 kHz indicates that the signal is re-processed to remove all vibrations which have frequency greater than 1 kHz and hence is the ‘harshest’ filter. As it is possible to apply a different filter to the same original signal, the influence o f filter frequency on peak force, peak energy and failure energy can be studied.

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Rheological characteristics of flours milled from different wheat varieties (Triticum aestivum L.)

Rheological characteristics of flours milled from different wheat varieties (Triticum aestivum L.)

Technological quality was studied of wheat fl ours from three varieties of Triticum aestivum L. (Arida, Meritto, Verita) delivered to the mill for three years (2007–2009). Physico-chemical parameters ob- served during the purchase of grain (STN 461100-2) were not signifi cantly diff erent. Also milled fl ours from tested varieties have by processors required ash content, gluten, acceptable Zeleny in- dex,  -amylase activity (falling number), but as the rheological properties of dough from these fl ours show, these parameters are unsuited enough (un)suitability of material for effi cient processing of fl our. Rheological evaluation showed that each variety is suitable for diff erent processing direc- tion. Therefore, if we deliberately separate lots of purchased grain, not only by basic physico-che mi- cal properties listed in the current standards (CSN and STN), but also by their rheological proper- ties, which are important and reliable indicator of the direction of the end-use processing of wheat fl ours, the fl ours will be more likely to succeed in specifi c cereal technology. For the production of bread was satisfactory rheological properties of dough from variety Arida. Verita variety is suitable for processing into wafers, and a variety Meritto for producing biscuits and crackers. Verita and Me- rit to varieties so do not achieved the expected values of the rheological optimum for „classic“ bread processing (bakery products) despite satisfactory gluten content and falling number to use this pro- cessing direction. Reported results show us the possibilities of more effi cient selection of varieties or lots purchased grain of wheat for use in baking and buscuit industry by using rheological evaluation methods. Results were evaluated by analysis of data exploration (Boxplot, scattering graphs), classical nonparametric testing of hypotheses and the distribution of the data (Wilcoxon test, Kruskal-Wallis, Friedman, rates central tendency and dispersion).

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Numerical simulation of ground vibration caused by collapse of a super-large cooling tower under strong earthquake

Numerical simulation of ground vibration caused by collapse of a super-large cooling tower under strong earthquake

Falling weight tests were conducted to vertify the “falling weight-soil”model built by Lin et al. (2013). Dynamic compaction was adopted to increase the density of the underlying soils. As indicated in Figure 1, dynamic compaction machinery slung a weight (with 12 ton in weight and about 2.5 m in diameter) to an appropriate height (about 5.9 m in the tests), and then made the weight fall with the aid of a self-release mechanism. The weight dropped freely and impacted the soil surface at a tamping point and, consequently, induced ground vibration. As a numerical experimentation, a finite element method (FEM) based “falling weight-soil” model was developed for the prediction of the ground vibration caused by a falling weight impacting onto the surface of the soil. For verification of the model, the results from the falling weight tests were used. The results of “falling weight-soil” model agreed well with those of site tests which indicated that the simulation model was feasible and reliable (Lin et al., 2013).

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Stumbling, Not Falling

Stumbling, Not Falling

Patti Rose’s cultural competency continuum maps six stages of behaviour and thought that detail the stages of cultural competency. The continuum spans from “cultural destructiveness” to “cultural proficiency” (2011, p. 57). These stages detail how one’s understanding of culture can evolve from a harmful, negative approach to one that is capable of fully integrating cultural competency into daily practices. When examined through this continuum, Healthy Aging falls within the fourth stage known as “cultural precompetency,” where there is a “clear commitment to human and civil rights” and “a desire to support culturally and linguistically diverse populations,” yet there is “no clear plan for achieving organizational cultural competence” (2011, p. 60). The report fits into this definition of cultural precompetency. The researchers acknowledge that the risks of falling for older Indigenous people are higher and costlier than they are for non-Indigenous people, and the report was created because there was little understanding as to why this is happening. Yet it only begins to acknowledge that the issue may have cultural roots. Hopefully, the research can move through the remaining stages of Rose’s continuum to ultimately reach a place of cultural proficiency, the most aware and effective position of the continuum. While cultural precompetency is not in and of itself negative and is, in fact, a necessary stage of progress towards proficiency, the article has limitations that, when addressed, could move fall-prevention research further along the continuum.

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Pollen Findings in a Presumptive  Drowning Case

Pollen Findings in a Presumptive Drowning Case

Drowning, as water aspiration to death, has extensively been discussed in medicolegal cases, and immersions are commonly solved by diatoms (microalgae), strontium (Sr) and other trace elements analyses [4]-[9]. Some drownings are sometimes difficult to resolve and a joint determination of Sr and other biochemical markers like Fe has been recommended [9] [10]. However, haemodilution is not so evident in some samples [9] and other form elements might be relevant apart from diatoms. Besides, significant differences in the amount of strontium absorbed into the bloodstream from fresh water are much lower than in seawater [6] and that is an inconven- ience for diagnosis resolving. Freshwater drownings (FWD) are even more difficult to research if no blood can be analysed because of the long post-mortem interval (PMI). Hereby the pollen study recovers importance when diatoms and microalgae are absent in the analysed organs. To this respect, there is very scarce mention or no mention of pollen with relation to drowning or the diagnosis of death in literature [11]. We present a FWD case and the correlated information of death circumstances, autopsy and microscopic findings, suggesting the pollen analysis as one optional tool for forensic diagnosis.

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Reducing the effects of DoS attacks in software defined networks using parallel flow installation

Reducing the effects of DoS attacks in software defined networks using parallel flow installation

In SDN, the controller being a centralized authority, keeps and maintains the updated information about the whole network. The routing process is also managed by the con- troller with the help of OF messages, such as Packet-In, Packet-Out, Flow-Add, etc. [2]. Switches contain flow tables to store flow rules for a limited time and forward data according to these rules. The controller keeps the network topology in its database to provide efficient and timely routing to the connected nodes. The routing applications/ modules in well-known open-source SDN controllers, such as Floodlight (circuit pusher) [13], ONOS (fwd) [14], Ryu (simple_switch, simple_switch_12, simple_switch_13) [15], and POX (L2_learning, L3_learning) [16], etc., install the flow rules on OF switches in a linear fashion, where each switch in the path between the source and the destination sends a Packet-In message toward the controller in order to get the flow rule to forward newly arrived data. The network diagram shown in Fig.  1 explains the routing process between the source (Host-1) and the destination (Host-8) in SDN.

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EXPERIMENTAL INVESTIGATION OF WALL EFFECT ON DRAG COEFFICIENT OF DIFFERENT PARTICLES SHAPE MOVING IN NEWTONIAN AND NON-NEWTONIAN FLUIDS.

EXPERIMENTAL INVESTIGATION OF WALL EFFECT ON DRAG COEFFICIENT OF DIFFERENT PARTICLES SHAPE MOVING IN NEWTONIAN AND NON-NEWTONIAN FLUIDS.

direction also in this study introduce the (FW) is the wall effect on the particle defined as it is a retardation effect on the particle sedimentation in fluid movement through the presence of the walls, the particle during sedimentation moved the fluid towards the top equal to the volume of the particle volume and have the fluid movement of reverse movement of the particle thus when the wall present this lead to lower the settling velocity, Brown, Phillip P(2003). The understanding and knowing the effect of wall on drag coefficient and about the settling velocity of a particle moving in fluid Newtonian and non-Newtonian is important and necessary for different theoretical and practical application in engineering such as design of thickeners, fluidized bed equipment, falling particle viscometer, Mingzhong Li (2014). Where the suspension or settling of solid particle will occur in chemical unit operation, also used to help design solid liquid mixture, clarifiers, Daoyun Song (2011). In environmental engineering such as processes in water treatment (flocculation, sedimentation, flotation and filtration) particle capture, and deposition in air, drilling for oil and gas, geothermal drilling, Philip P .Brown (2003). It is well known that presents walls produced a retardation force effect on a particle settling in fluid and the direction upward the effect of bounded walls .the wall effect can be calculated or describe is by using the wall correction factor (FW) which can be expressed as: ( 𝐹𝑊 = 𝑉

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Bread wheat quality: some physical, chemical and rheological characteristics of Syrian and English bread wheat samples

Bread wheat quality: some physical, chemical and rheological characteristics of Syrian and English bread wheat samples

The results of our research illustrate variations between Syrian genotypes in vitreousness, kernel weight and test weight; differences were also noticed in protein content, falling number, flour water absorption and the colour of the flour in all Syrian and English samples. Experimental lines, Doumah-40765 and Doumah-46055 exhibited reduced vitreousness and protein content compared to any of the other genotypes. Samples showed clear differences in dough and bread characteristics (resilience and firmness). The differences in physical, chemical and rheological characteristics between samples did not give significant variations in specific loaf volume, but those differences affected the quality of the loaf. Bread sensory analysis clearly demonstrated the effect of the kernel physical characteristics, flour chemical traits and the dough rheology on bread quality. Colour, appearance and texture were the major factor in bread evaluation. Results proved conclusively the validity of the Syrian genotypes for Western style bread making which is not one of the mostly commonly produced bread on the Syrian market. The Syrian variety Doumah-2 was the most appreciated among all samples, while Doumah 40765 and 46055 were the least appreciated by the assessors which may suggest their suitability for biscuit preparation rather than bread making. Correlation analyses confirmed the importance of the vitreousness, protein content and the rheological traits of dough on the quality of bread especially the resilience and firmness. It is common in breeding programs to assess the suitability of grain solely on the properties of the raw material. In this study, sensory analysis was prioritized to assess bread quality rather than relying on judging the quality of the final product merely through quantitative evaluation of kernel and flour characteristics.

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Possibility of selenium biofortification of winter wheat grain
 

Possibility of selenium biofortification of winter wheat grain  

Two-year average results of volume weight of grain, portion of the first class grain, thousand ker- nel weight, wet gluten content, Zeleny sedimenta- tion value and falling number of winter wheat grain was not significantly affected by different doses (10 and 20 g Se/ha) of either selenite or selenate foliar application (Tables 3 and 4). No significant Table 2. Effect of different doses of both selenite and selenate foliar applications on winter wheat grain yield

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Front Wheel Drive, Rear Wheel Drive, And Four Wheel Drive Effect Comparison To Vehicle Directional Stability

Front Wheel Drive, Rear Wheel Drive, And Four Wheel Drive Effect Comparison To Vehicle Directional Stability

The controversy has gone on for decades in deciding the vehicle directional stability for Four Wheel Drive vehicle (4WD), Rear Wheel Drive vehicle (RWD), and Front Wheel Drive vehicle (FWD). The argument on the directional stability often concerns with handling of the vehicle during cornering. Through this research, it is hoped that simulation done can help to provide more detail information to the public in deciding which vehicle suits them best. Moreover the research could act as guidance for further studies, students’ references or even assist racers in having a better choice.

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Usage Surface Deflection Data for Performance Prediction in Flexible Pavement

Usage Surface Deflection Data for Performance Prediction in Flexible Pavement

The conventional method used for calculating pavement condition index (PCI) has two major drawbacks: safety problems during pavement inspection, and human error. This paper proposes a method for removing these problems. The proposed method uses surface deflection data in falling weight Deflectometer test to estimate PCI. The data used in this study were derived from 236 pavement segments taken from Tehran-Qom freeway in Iran. The data set was analyzed using multi layers perceptron (MLP) and radial basis function (RBF) neural networks. These neural networks were optimized by levenberg-marquardt (MLP-LM), scaled conjugate gradient (MLP-SCG), imperialist competitive (RBF-ICA), and genetic (RBF-GA) algorithms. After initial modeling with four neural networks mentioned, the committee machine intelligent systems (CMIS) method was adopted to combine the results and improve the accuracy of the modeling. The results of analysis have been verified by the four criteria of average percent relative error (APRE), average absolute percent relative error (AAPRE), root mean square error (RMSE) and standard error (SD). The best reported results belonged to CMIS, including APRE=2.3303, AAPRE=11.6768, RMSE=12.0056, and SD=0.0210.

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