A review of cost and profit oriented line design and balancing problems and solution approaches

2015 ◽  
Vol 40 ◽  
pp. 14-24 ◽  
Author(s):  
Öncü Hazır ◽  
Xavier Delorme ◽  
Alexandre Dolgui
Keyword(s):  
Author(s):  
Benedict Scheiner ◽  
Christopher Beck ◽  
Fabian Lurz ◽  
Martin Frank ◽  
Fabian Michler ◽  
...  

PIERS Online ◽  
2008 ◽  
Vol 4 (4) ◽  
pp. 433-436 ◽  
Author(s):  
Yaping Liang ◽  
Calvin W. Domier ◽  
Neville C. Luhmann, Jr.

Machines ◽  
2021 ◽  
Vol 9 (3) ◽  
pp. 60
Author(s):  
Khaled Alawadhi ◽  
Bashar Alzuwayer ◽  
Tareq Ali Mohammad ◽  
Mohammad H. Buhemdi

Since centrifugal pumps consume a mammoth amount of energy in various industrial applications, their design and optimization are highly relevant to saving maximum energy and increasing the system’s efficiency. In the current investigation, a centrifugal pump has been designed and optimized. The study has been carried out for the specific application of transportation of slurry at a flow rate of 120 m3/hr to a head of 20 m. For the optimization process, a multi-objective genetic algorithm (MOGA) and response surface methodology (RSM) have been employed. The process is based on the mean line design of the pump. It utilizes six geometric parameters as design variables, i.e., number of vanes, inlet beta shroud, exit beta shroud, hub inlet blade draft, Rake angle, and the impeller’s rotational speed. The objective functions employed are pump power, hydraulic efficiency, volumetric efficiency, and pump efficiency. In this reference, five different software packages, i.e., ANSYS Vista, ANSYS DesignModeler, response surface optimization software, and ANSYS CFX, were coupled to achieve the optimized design of the pump geometry. Characteristic maps were generated using simulations conducted for 45 points. Additionally, erosion rate was predicted using 3-D numerical simulations under various conditions. Finally, the transient behavior of the pump, being the highlight of the study, was evaluated. Results suggest that the maximum fluctuation in the local pressure and stresses on the cases correspond to a phase angle of 0°–30° of the casing that in turn corresponds to the maximum erosion rates in the region.


Author(s):  
Jaber Hussain Akbar ◽  
Ridwaan Omar ◽  
Yacoub Al Tarakmah

Statement of problem- Research on evaluation of crowns made by the latest CAD/CAM systems for their marginal adaptation is scarce. Purpose- The purpose of this in vitro study was to evaluate the marginal integrity of crowns fabricated by the latest Chairside Economical Restorations of Esthetic Ceramic (CEREC) system using two different finish line preparation designs: Chamfer and Shoulder. Material and methods- Typhodont teeth were equally divided into two groups, group A and B. The teeth were prepared for full coverage crowns with a shoulder (group A) and chamfer finish line design (group B). An experienced prosthodontist prepared all crown preparations. Evaluation of six sites per sample was completed by two calibrated, experienced prosthodontists using the modified United States Public Health Services (USPHS) criteria. The descriptive statistics and Z-test were used to evaluate the results. Results- A total of 180 teeth were included in the study (90 teeth in each group). Only two crowns in group A and one crown in group B were clinically unacceptable. There was no statistical significance (p=0.282) between the two groups regarding finish-line design. Conclusions- CEREC system provides clinically acceptable crowns and can safely be utilized in dental treatment. Therefore, Contemporary Dental Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM) restorations should be considered as a safe treatment modality by dental professionals.


2019 ◽  
Vol 52 (13) ◽  
pp. 247-252 ◽  
Author(s):  
Serena Finco ◽  
Mohammed-Amine Abdous ◽  
Daria Battini ◽  
Martina Calzavara ◽  
Xavier Delorme
Keyword(s):  

2020 ◽  
Vol 3 (4) ◽  
pp. 42
Author(s):  
Albert Sabban

The development of compact passive and active wearable circular patch metamaterials antennas for communication, Internet of Things (IoT) and biomedical systems is presented in this paper. Development of compact efficient low-cost wearable antennas are one of the most significant challenges in development of wearable communication, IoT and medical systems. Moreover, the advantage of an integrated compact low-cost feed network is attained by integrating the antenna feed network with the antennas on the same printed board. The efficiency of communication systems may be increased by using efficient passive and active antennas. The system dynamic range may be improved by connecting amplifiers to the printed antenna feed line. Design, design considerations, computed and measured results of wearable circular patch meta-materials antennas with high efficiency for 5G, IoT and biomedical applications are presented in this paper. The circular patch antennas electrical parameters on the human body were analyzed by using commercial full-wave software. The circular patch metamaterial wearable antennas are compact and flexible. The directivity and gain of the antennas with Circular Split-Ring Resonators (CSRR) is higher by 2.5dB to 3dB than the antennas without CSRR. The resonant frequency of the antennas without CSRR is higher by 6% to 9% than the antennas with CSRR. The computed and measured bandwidth of the stacked circular patch wearable antenna with CSRR for IoT and medical applications is around 12%, for S11 lover than −6dB. The gain of the circular patch wearable antenna with CSRR is around 8dBi.


Sign in / Sign up

Export Citation Format

Share Document