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Erosion has been recognized as one of the major threats for industries involving multiphase transportation pipelines. Within the last decades, effective parameters on wear pattern have been identified. As a result, the (famous) V-shaped erosion profile has been detected for the pipes' elbow section. In this study, CFD is employed to investigate the erosion mechanism on the square duct elbows. A novel erosion pattern has been observed for square ducts in comparison with the pipes. The impact of several parameters (particle and flow velocity, secondary flow, turbulent intensity, particle streamline) has been inspected as well. It has been led to the conclusion that the erosion rate of square ducts is lower than common pipes, especially when either higher flow velocities or bigger particles size are employed.

Failure mode and effect analysis (FMEA) model is a technique used to evaluate the risk. This paper aimed to propose a new FMEA model combining technique for order of preference by similarity to ideal solution (TOPSIS) and belief structure to overcome the shortcomings of the traditional index of FMEA. In this paper, the fuzzy belief TOPSIS method is combined with FMEA to introduce a belief structure FMEA to describe the expert knowledge by a number of linguists as a grammatical phenomenon. Moreover, the weights of components in FMEA index can be different from each other. Therefore, the flexibility of assigning weight to each factor in this method is more compatible to the real decision-making situation. In other word, TOPSIS method is applied to determine the preference of alternatives versus risk criteria. Using linguistic terms in the fuzzy belief approach, the risk factors described a more meaningful value and decision-makers’ judgment is assigned with belief degrees through evaluation of factors. Finally, a numerical case study about the preference of cause failures of steel production process is provided to illustrate the process of proposed method, and then result and discussion is performed for each case.

SUMMARY In this paper, a biomechanical study of a human head model exposed to blast shock waves followed by a blunt impact with the surface of the enclosing walls of a confined space is carried out. Under blast, the head may experience primary blast injury (PBI) due to exposure to the shockwaves and tertiary blast injury (TeBI) due to a possible blunt impact. We examine the brain response data in a deformable finite element head model in terms of the inflicted stress/pressure, velocity, and acceleration on the brain for several blast scenarios with different intensities. The data will be compared for open space and confined spaces. Following the initial impact of the shock front in the confined space, one can see the fluctuations in biomechanical data due to wave reflections. Although the severity of the PBI and TeBI is dependent on the situation, for the cases studied here, PBI is considerably more pronounced than TeBI in confined spaces. Copyright © 2014 John Wiley & Sons, Ltd.

In this paper, a computational modeling for biomechanical analysis of primary blast injuries is presented. The responses of the brain in terms of mechanical parameters under different blast spaces including open, semi-confined, and confined environments are studied. In the study, the effect of direct and indirect blast waves from the neighboring walls in the confined environments will be taken into consideration. A 50th percentile finite element head model is exposed to blast waves of different intensities. In the open space, the head experiences a sudden intracranial pressure (ICP) change, which vanishes in a matter of a few milliseconds. The situation is similar in semi-confined space, but in the confined space, the reflections from the walls will create a number of subsequent peaks in ICP with a longer duration. The analysis procedure is based on a simultaneous interaction simulation of the deformable head and its components with the blast wave propagations. It is concluded that compared with the open and semi-confined space settings, the walls in the confined space scenario enhance the risk of primary blast injuries considerably because of indirect blast waves transferring a larger amount of damaging energy to the head.

Vibro-acoustic techniques have been developed with the aim of determining the location of buried pipes. However, the characteristics of the recorded conical wave radiation from the pipe wall to the surface, at very low frequencies, have not been investigated in depth.

The influence of tortuosity and fluid volume fractions on trickle-flow bed performance was analyzed. Hydrodynamics of the gas-liquid downward flow through trickle beds, filled with industrial trilobe catalysts, were investigated experimentally and numerically. The pressure drop and liquid holdup were measured at different gas and liquid velocities and in two different loading methods, namely, sock and dense catalyst loading. The effect of sharp corners on hydrodynamic parameters was considered in a bed with rectangular cross section. The reactor was simulated, considering a three-phase model, appropriate porosity function, and interfacial forces based on the Eulerian-Eulerian approach. Computational fluid dynamics (CFD) simulation results for pressure drop and liquid holdup agreed well with experimental data. Finally, the velocity distribution in two types of loading and the effect of bed geometry in CFD results demonstrated that pressure drop and liquid holdup were reduced compared to a cylindrical one due to high voidage at sharp corners.

The nonlinear free vibration of nanobeams with considering surface effects (surface elasticity, tension and density) is studied using Euler–Bernoulli beam theory including the von karman geometric nonlinearity. The component of plane stress, σ zz , is assumed to vary linearly through the beam thickness and satisfy the balance conditions between nanobeam bulk and its surfaces. Accordingly, surface density is introduced into the governing equation of the nonlinear free vibration of nanobeams. It is seen that the effect of surface density is independent of amplitude ratio. In addition, it is observed that in lower modes, surface density has insignificant effects on the variation of the natural frequency versus mode number, whereas this is not the case in higher modes where the surface density causes the normalized natural frequencies of the nanobeams to increase drastically. Moreover, it is shown that the effect of the surface density on the variation of the natural frequency of the nanobeam versus the thickness ratio decreases consistently with the increase of the mode number.

Experimental data on the hemodynamics of dental pulp at different stages of caries treatment are given. Observations of speckle patterns in backscattered laser light are used as a measurement method to qualitatively characterize changes in blood flow rate through the dental pulp. The measurements were made by the author-designed experimental setup. Theoretical estimations showed that stationary reflected light from an in vivo tooth contains a negligibly small information body on changes in the pulpal blood flow due to the shadowing of the pulp by optically thick enamel and dentin. Therefore, the temporal variations in the speckle patterns are the only possible way that can provide monitoring of blood conditions in the pulp by using backscattered light. Various statistical characteristics of the random reflected light fields are studied as indicators of blood flow rate changes. There were selected five statistical parameters of backscattered speckle images that give self-consistent data on these changes. The parameters include four combinations of integrals of the Fourier transforms of the observed temporal variations as well as the speckle image contrast. The selected parameters are shown to qualitatively agree with general considerations on the effects of reduced or increased blood flow rates on the selected integral quantities.

The results of a computational study on the effect of the body on biomechanical responses of a helmeted human head under various blast load orientations are presented in this work. The focus of the work is to study the effects of the human head model boundary conditions on mechanical responses of the head such as variations of intracranial pressure (ICP). In this work, finite element models of the helmet, padding system, and head components are used for a dynamic nonlinear analysis. Appropriate contacts and conditions are applied between different components of the head, pads and helmet. Blast is modeled in a free space. Two different blast wave orientations with respect to head position are set, so that, blast waves tackle the front and back of the head. Standard trinitrotoluene is selected as the high explosive (HE) material. The standoff distance in all cases is one meter from the explosion site and the mass of HE is 200 grams. To study the effect of the body, three different boundary conditions are considered; the head-neck model is free; the base of the neck is completely fixed; and the head-neck model is attached to the body. Comparing the results shows that the level of ICP and shear stress on the brain are similar during the first five milliseconds after the head is hit by the blast waves. It explains the fact that the rest of the body does not have any contribution to the response of the head during the first 5 milliseconds. However, the conclusion is just reasonable for the presented blast situations and different blast wave incidents as well as more directions must be considered.Copyright © 2013 by ASME

Modeling and optimization of welding processes is one of the important topics for welding researches. In such research, it is necessary to measure the weld bead geometry. Nowadays, machine vision has a widespread use in measurement applications. In order to use machine vision in weld bead geometry measurement, it is necessary to acquire the desired images of cross section of welded plates with desirable separation of weld and base metal regions. This separation is performed by suitable solution to etch cross section of welded plates. In this paper, it has been tried to determine suitable solution to etch cross section of welded plates (made from API X56 steel) for obtaining the best revelation of weld metal regions. This solution can be utilized to obtain desired image of welded plate's cross section for machine vision measurement of weld bead geometry.

Stress is a kind of physical or psychological exhaustion caused by actual or superficial problems. When pressures in working environment build up, a considerable impact on body and mind can be developed. This condition may lead the worker in to a harmful accident and bring about a dangerous situation. In many countries forestry is one of the toughest and most difficult types of occupation. Working in forest is intensive and involves a high degree of risk. Operating chainsaw and skidder are known as two most stressful occupations in forest. In order to study effect of occupational stress on mental health of forest workers, a research was conducted on the workers of two companies Mazandaran Wood and Paper Manufactory and Nekachoob Wood Technology using GHQ-28 questionnaire (General Health Questionnaire). Furthermore, in order to investigate and compare forest workers under impact with greater details, control group was also considered. Kroskal-Wallis test showed that there was a significant difference between target and contro groups in terms of mental health at 99 percent statistical levels. Working conditions and occupational stress had negative impact on mental health of both chainsaw and skidder operators so seriously that they showed symptoms like anxiety, nervousness, lack of sleep, etc.

11052 Background: TAC confers a significant disease free and overall survival benefits vs. FAC for patients with node positive breast cancer and prophylactic use of G-CSF is a reasonable supportive therapy to minimize myelosuppresive complications of this regimen. DD scheduling has shown improved clinical outcomes in breast cancer therapy. This study is trying to compare toxicities and tolerability of DD TAC with G-CSF support with TAC every 3 wks supported with G-CSF. Methods: Thirty seven patients were enrolled during the period 1/04 to 1/06. Cohort A (N=25) received six cycles of TAC (75/50/500 mg/m2 every 3 wks) plus GCSF started on day 5 and Cohort B (N=12) received six cycles of TAC (75/50/500 mg/m2 every 2 wks) plus GCSF started on day 2. All patients had normal cardiac, renal and liver function. Toxicities were evaluated by clinical assessment, CBC and liver function tests. Results: The incidence of febrile neutropenia was 15.8% and 16.7% in cohort A and B respectively (RR =1.06, 95% CI = 0.20–5.42). Grade III/IV anemia was detected in 5.3% of cohort A patients and 8.0 % of cohort B patients (RR=1.58, 95% CI=0.10–22.99). Ten percent of cohort A patients developed stomatitis grade III/IV while none of cohort B patients had this toxicity (RR=1.06, 95% CI = 0.94–1.17). Hospitalization due to chemotherapy complications (mainly neutropenia) in cohort A and B were 5.3% and 8.3% (RR =1.58, 95%CI = 0.10–22.99). Conclusions: DD two weekly TCA was reported to be feasible in patients with stage II - III breast cancer (Margolis et al. JCO, 2005). This study shows that DD TCA plus G-CSF has comparable toxicity profile with standard TCA regimen with shorter treatment period.

1. Perphenazine, promethazine and levomepromazine induced sedation in young pullets following intramuscular injections. 2. The best results were obtained with perphenazine at a dose rate of 1-5 mg/kg.

An account is given of the development of a ring rolling process for the manufacture of V-sectioned rings from thin-walled plain cylinders. The rings were required in different diameters and sectional dimensions for a specific application, and in the absence of any design information an analysis of the forming process was made to provide guidance on the design of the forming rolls. The analysis is shown to predict satisfactorily the conditions needed for smooth development of the profile and the blank size required to produce a given ring size.