Evaluation of Optimum Parameters for Casting of Birla Lance Pipes

2021 ◽  
pp. 13-23
Author(s):  
Dinesh S. Shinde ◽  
Ashnut Dutt ◽  
Ranjan Kumar Ghadai ◽  
Kanak Kalita ◽  
Amer Nasr A. Elghaffar
Keyword(s):  
Critical Role ◽  
Flow Time ◽  
Process Parameter ◽  
Main Concern ◽  
Casting Defect ◽  
Pouring Temperature ◽  
Taguchi Analysis ◽  
Optimum Parameters ◽  
The Difference ◽  
Spinning Speed

Defects associated with casting of pipes are often a main concern for the industry. In this chapter, a Taguchi analysis is carried out to understand the effect of three process parameter pouring temperature (°C), die spinning speed (rpm), and coolant flow time (mins) on the casting defect of pipes. The defect is defined in this work as the difference between the desired thickness of the pipe and the minimum actual (experimentally) achieved. A L9 orthogonal array is designed to carry out the experiments. Based on the S/N ratio analysis and ANOVA, it is seen that the die spinning speed plays the most critical role in defect of the pipes. As per the conducted experiments and Taguchi analysis, pouring temperature is seen to have the lest influence on the defects.

Preparation of Semisolid A356 Alloy by a Cooling Slope Processing

2011 ◽  
Vol 675-677 ◽  
pp. 767-770 ◽  
Author(s):  
Jun Xu ◽  
Tong Min Wang ◽  
Zong Ning Chen ◽  
Jing Zhu ◽  
Zhi Qiang Cao ◽  
...  
Keyword(s):  
A356 Alloy ◽  
A356 Aluminum Alloy ◽  
Forming Process ◽  
Pouring Temperature ◽  
Cooling Slope ◽  
Optimum Parameters ◽  
Grain Structures ◽  
Semisolid Forming ◽  
Size And Morphology ◽  
A356 Aluminum

In order to obtain the non-dendritic feedstock for the semisolid forming process, a cooling slope processing was used. In this work, the effects of the angle, length of cooling slope and pouring temperature on the microstructure of A356 aluminum alloy were investigated. It showed that these parameters affect the size and morphology of α-Al phase to some extent. The results indicate that a pouring temperature of 650°C and a cooling slope with 45° in angle and 50 cm in length are the optimum parameters for preparing fine and globular grain structures. To eliminate the solidification shell formed in the surface of cooling slope, a nitride dope was coated on the surface of the cooling slope.

Voting Equilibria Under Proportional Representation

2014 ◽  
Vol 108 (2) ◽  
pp. 281-296 ◽  
Author(s):  
SEOK-JU CHO
Keyword(s):  
Median Voter ◽  
Critical Role ◽  
Solution Concept ◽  
Proportional Representation ◽  
Policy Outcomes ◽  
Main Concern ◽  
Policy Outcome ◽  
Equilibrium Concept ◽  
Number Of Parties ◽  
Robust Equilibrium

This article studies the consequences of strategic voting by outcome-oriented voters in elections under proportional representation (PR). I develop a model of elections under PR, in which voters choose among an arbitrary finite number of parties, and the policy outcome is determined in a postelection bargaining stage. I use a new solution concept, robust equilibrium, which greatly mitigates the well-known problem of indeterminate predictions in multicandidate competition. Applying the equilibrium concept to the model, I find that PR promotes representation of small parties in general, even when voters are strategic. However, the median voter plays a critical role in shaping policy outcomes, which reflects the majoritarian nature of parliamentary policy making rules. Thus, PR may not be incompatible with the majoritarian vision of representative democracy if voters’ main concern is policy outcomes.

Migrating Progenitor Cells Derived From Injured Cartilage Surface Respond to Damage-Associated Molecular Patterns

Cartilage ◽  
2021 ◽  
pp. 194760352110495
Author(s):  
Lei Ding ◽  
Cheng Zhou ◽  
Hongjun Zheng ◽  
Quanming Wang ◽  
Haiyan Song ◽  
...  
Keyword(s):  
Articular Cartilage ◽  
Progenitor Cells ◽  
Quantitative Polymerase Chain Reaction ◽  
Critical Role ◽  
Cartilage Degeneration ◽  
Expression Levels ◽  
Chondrogenic Progenitor Cells ◽  
The Difference ◽  
Molecular Patterns ◽  
Damage Associated Molecular Patterns

Objective: To delineate the response of migrating chondrogenic progenitor cells (CPCs) that arose from the surface of mechanically injured articular cartilage to proinflammatory damage-associated-molecular-patterns (DAMPs). Design: Bovine CPCs and non-CPC chondrocytes isolated from either impacted or scratched articular cartilage were studied. Those 2 types of cells were treated with mitochondrial DAMPs (MTDs; 10 nM fMLF and 10 µg/mL CpG DNA), or 10 nM HMGB1, or 10 ng/mL IL-1b for 24 hours. At the end of experiments, conditioned media and cell lysates were collected for analysis of expression levels of matrix metalloproteinases (MMPs), chemokines, and cytokines that are associated with cartilage degeneration with Western blotting and quantitative polymerase chain reaction. The difference of expression levels was compared by Welch’s t-test. Results: Our data indicated that HMGB1 and MTDs remarkably upregulated pro-MMP-13 expression in CPCs. Compared with non-CPCs, CPCs expressed significantly more baseline mRNAs of MMP-13, CXCL12, and IL-6. MTDs greatly increased the expression of MMP-13 and IL-6 in CPCs by over 100-fold ( P < 0.001). MTDs also significantly increased IL-8 expression in CPCs to a similar extent ( P < 0.001). However, when IL-1b was present, CPCs expressed less MMP-3 and active MMP-13 proteins as well as less CCL2 and IL-6 than did non-CPCs. Conclusions: We concluded that CPCs were more sensitive than non-CPCs in response to DAMPs, especially MTDs. The proinflammatory nature of CPCs implied their critical role in the early phase of posttraumatic osteoarthritis development.

scholarly journals Dialysate Calcium Levels: Do They Matter?

2018 ◽  
Vol 47 (1-3) ◽  
pp. 230-235 ◽  
Author(s):  
Frank M. van der Sande ◽  
Karlien J.A. ter Meulen ◽  
Peter Kotanko ◽  
Jeroen P. Kooman
Keyword(s):  
Vitamin D ◽  
Critical Role ◽  
Essential Element ◽  
Vascular Pathology ◽  
Phosphate Binders ◽  
Multiple Parameters ◽  
Vitamin D Analogues ◽  
Endocrine Disturbances ◽  
Increased Risk ◽  
The Difference

Background: Calcium (Ca) is an essential element that plays a critical role in many biological processes. In dialysis patients, the regulation of Ca balance is highly complex, given the absence of kidney function, endocrine disturbances and the use of drugs such as phosphate binders, vitamin D analogues, and calcimimetics. Also, the use of different dialysate Ca (DCa) baths has profound effect on Ca balance, which depends both on the difference between the Ca concentration in the bath and the serum of the patients, as on the ultrafiltration volume. Summary: The choice of DCa may have important short- and long-term consequences. While lower DCa (especially < 2.5 mEq/L) concentrations have been associated with an increased risk of sudden cardiac death in observational studies, DCa in the higher ranges (3.0 mEq/L and above) may contribute to vascular pathology. Intra-dialytic hemodynamics may also be affected by the choice of DCa. In general, lower DCa concentrations are associated with an increase, and higher DCa concentrations with a decrease in parathyroid hormone (PTH) levels. Preliminary data has suggested that a DCa of 2.75 mEq/L may help in obtaining a net zero intradialytic Ca balance in individual patients, but clinical experience is still limited. Key Message: The optimal Ca balance depends on multiple parameters including blood Ca levels, PTH and the use of phosphate binders and vitamin D analogues, as well as on the risk of hemodynamic stability and cardiac arrhythmias. Therefore, DCa prescription should be individualised. A DCa of 2.75 mEq/L may be useful adjunct for dialysis providers.

scholarly journals What we think we know about newton’s principia

2018 ◽  
Vol 5 (12) ◽  
pp. 171
Author(s):  
Raquel Anna Sapunaru ◽  
Gabriela Fernandes
Keyword(s):  
Main Concern ◽  
Physics Teaching ◽  
Philosophical Approach ◽  
Physics Teachers ◽  
The Difference ◽  
The One ◽  
Contemporary Interpretation

In this article we examine some of the most controversial points in Newton's Principia regarding the contemporary interpretation: the assumed circularity of Definition I, the difference between vis insita and vis inertia, Law I and Law II. The main goal of this work is to offer a wider view of Newton’s writings and provide a historic philosophical approach to the physics teachers which will certainly be useful in physics teaching. We also discuss the modern terminology compared to the one used by Newton himself. Our main concern is to aid the deconstruction of preconceived ideas regarding the Principia which are fairly common among physics teachers.

A BEST POSSIBLE ONLINE ALGORITHM FOR SCHEDULING TO MINIMIZE MAXIMUM FLOW-TIME ON BOUNDED BATCH MACHINES

2014 ◽  
Vol 31 (04) ◽  
pp. 1450030 ◽  
Author(s):  
CHENGWEN JIAO ◽  
WENHUA LI ◽  
JINJIANG YUAN
Keyword(s):  
Competitive Ratio ◽  
Completion Time ◽  
Online Algorithm ◽  
Unit Length ◽  
Maximum Flow ◽  
Flow Time ◽  
Release Time ◽  
Batch Machine ◽  
The Difference ◽  
Over Time

We consider online scheduling of unit length jobs on m identical parallel-batch machines. Jobs arrive over time. The objective is to minimize maximum flow-time, with the flow-time of a job being the difference of its completion time and its release time. A parallel-batch machine can handle up to b jobs simultaneously as a batch. Here, the batch capacity is bounded, that is b < ∞. In this paper, we provide a best possible online algorithm for the problem with a competitive ratio of [Formula: see text].

The wettability and micro-equilibrium of different essence liquids to alkali-treated kapok fiber

2021 ◽  
pp. 004051752110320
Author(s):  
Liyao Cao ◽  
Yanfang Xu ◽  
Kaifang Xie ◽  
Fumei Wang ◽  
Guangbiao Xu
Keyword(s):  
Theoretical Model ◽  
Critical Role ◽  
Error Rates ◽  
Adhesion Energy ◽  
Phase Contact ◽  
Fiber Network ◽  
Kapok Fiber ◽  
Three Phase ◽  
The Difference ◽  
Kapok Fibers

Kapok fiber is a natural hollow fiber that has superior biocompatibility and biodegradability and is naturally antibacterial. Because of its unique properties, it has great potential in the application of postoperative repair dressings. The wettability and micro-equilibrium of kapok fibers play a critical role in dressing applications. In this study, the critical adhesion volume and adhesion energy of essence liquid to alkali-treated kapok fiber (AKF) were quantitatively calculated to explore the wettability and micro-equilibrium through the equilibrium wetting theory. Meanwhile, the three-phase contact line (TCL) structure was described. The results showed that the critical adhesion volumes of the three types of essence liquid for AKF were 3.45, 3.81, and 4.12 μL, respectively. Moreover, the critical volumes and low error rates derived from the equilibrium wetting theory were 3.41 μL and 1.16%, 3.99 μL and 4.51%, and 4.60 μL and 10.43%, respectively. Therefore, the critical volume of adhesion could be well calculated by the theoretical model. The average adhesive energies of essence liquid to the AKF were 0.38, 0.45, and 0.56 J, respectively, caused by the difference in liquids properties. The TCL showed a mechanical lock and bonding points at both ends because of the curvature difference and higher surface energy. These results are proposed to inspire the design of a liquid carrier of kapok fibers based on the fiber network structure.

HRM policies play critical role workers in reducing staff turnover in Chinese hotels

2020 ◽  
Vol 28 (6) ◽  
pp. 29-30
Keyword(s):  
Public Relations ◽  
Critical Role ◽  
Retention Rates ◽  
Staff Turnover ◽  
Staff Retention ◽  
Structured Interviews ◽  
High Turnover ◽  
Content Type ◽  
The Difference ◽  
The Impact

Purpose The authors wanted to study hotels because of the alarmingly high turnover of staff, which varies between 22% and 80% across countries. They said previous studies of the importance of HRM had addressed other different sectors in the hospitality industry. Design/methodology/approach The authors carried out semi-structured interviews with eight males and seven females aged between 23 and 52 years old. They were all at junior, or mid-management, level. They had experience of working in a lot of different departments, including marketing, HRM, front office, public relations and finance. The interviews of between 45 minutes and an hour were carried out in cafes. All names were changed in the paper. Findings The in-depth interviews revealed that the way in which HR departments implement policies makes all the difference to staff retention rates. The authors said their study demonstrated the powerful role of HR departments in hotels and that hotel employees expected them to play proactive roles in promoting their wellbeing at work. Originality/value Studies of the impact of HRM on staff turnover in the hotel sector in China have been rare.

scholarly journals Three-dimensional numerical assessment of axial and torsional interface shear behaviour

2019 ◽  
Vol 92 ◽  
pp. 13016
Author(s):  
Jiaxing Su ◽  
David Frost ◽  
Alejandro Martínez
Keyword(s):  
Wide Spectrum ◽  
Spatial Scales ◽  
Critical Role ◽  
Three Dimensional ◽  
Shear Behaviour ◽  
Discrete Element Modelling ◽  
Interface Shear ◽  
Model Studies ◽  
Soil Site ◽  
The Difference

Interfaces between geo-materials and soils play a critical role in a wide spectrum of geotechnical structures and soil/site characterization techniques in geotechnical engineering. Consequently, understanding the mechanics of interface shear behaviour at different scales can benefit both soil characterization and the design of geotechnical systems. This paper presents a series of numerical simulations that utilize the 3D discrete element modelling (DEM) technique and compares the results with those obtained from laboratory counterpart tests under axial and torsional axisymmetric interface shear. The difference observed in macro- and meso-scale responses under these loading conditions, such as shear strength, volumetric change, and shear zone characteristics are evaluated. In addition, responses at microscale including particle displacement trajectory, particles rotation, and local void ratio evolution are assessed allowing for links to the results obtained at larger spatial scales. These 3D numerical model studies expand the micromechanical processes under different shearing conditions previously presented by the authors from 2D to 3D space.

scholarly journals The migration ofAscaris suumlarvae, and the associated pulmonary inflammatory response in susceptible C57BL/6j and resistant CBA/Ca mice

Parasitology ◽  
2007 ◽  
Vol 134 (9) ◽  
pp. 1301-1314 ◽  
Author(s):  
R. Lewis ◽  
J. M. Behnke ◽  
J. P. Cassidy ◽  
P. Stafford ◽  
N. Murray ◽  
...  
Keyword(s):  
Inflammatory Response ◽  
Critical Role ◽  
Lavage Fluid ◽  
Intestinal Wall ◽  
Post Inoculation ◽  
Larval Stages ◽  
Stage Of Development ◽  
Pulmonary Inflammatory Response ◽  
The Difference ◽  
Susceptibility And Resistance

SUMMARYAscariasis is an important infection in humans (Ascaris lumbricoides) and pigs (Ascaris suum) and individuals appear to be predisposed to either heavy or light worm burdens. These extremes of susceptibility and resistance are represented in a mouse model by 2 strains of mice, CBA mice showing high resistance to infection and C57BL/6 which are highly susceptible, as reflected in worm burdens in the lungs 6–7 days after infection. In an attempt to identify the point at which the difference between these 2 strains is first manifested, we quantified worm burdens at key stages during infection leading up to the pulmonary stage of development. Thus mice were inoculated with fully embryonatedA. suumeggs and larval burdens were enumerated in the large intestine and rectum, liver and lungs of the 2 strains at 6 h post-inoculation (p.i.) and on each of days 1–8 p.i. inclusively. A higher percentage of the total inoculum was recovered from the intestine/rectum of C57BL/6j mice in contrast to CBA/Ca mice at 6 h p.i. Larvae were recovered from the intestinal contents and also whilst actively migrating through the large intestinal wall. The number of larvae recovered was significantly reduced in CBA/Ca mice in contrast to C57BL/6j mice between the phase of migration from the liver and arrival in the lungs. The combined results of the inoculation of mice with corticosteroids and the examination of the change in profile and number of leukocytes present in bronchoalveolar lavage fluid suggested that the pulmonary inflammatory immune response was not prominently involved in primary protection of mice toA. suuminfection in the latter days of infection in the lungs. The susceptible C57BL/6j mice produced a BAL response almost twice as intense as that of resistant CBA/Ca mice with stronger neutrophil, lymphocyte and eosinophil but not macrophage components, suggesting that the difference in worm burdens between the strains was generated earlier in the course of infection. These results were further corroborated by a histological examination of the lung tissues which showed that the passage of the larval stages ofA. suumthrough the mouse lungs was associated with a marked inflammatory response in both strains. Again, C57BL/6j mice exhibited increased inflammation relative to CBA/Ca mice. Hence some hepatic/post-hepatic factor that varies between the 2 strains, but exerts its effect before the lung phase plays a critical role in determining the success of larvae through the host tissues. The possible sites of this host defence are reviewed.

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