Implementation and performance study of lpCMFD acceleration method for multi-energy group k-eigenvalue neutron transport problem in hexagonal geometry

2020 ◽  
Vol 139 ◽  
pp. 107220 ◽  
Author(s):  
Yimeng Chan ◽  
Sicong Xiao
Keyword(s):  
Neutron Transport ◽  
Transport Problem ◽  
Performance Study ◽  
Energy Group ◽  
Acceleration Method ◽  
And Performance

Replication of the Superstition and Performance Study by

2014 ◽  
Vol 45 (3) ◽  
pp. 239-245 ◽  
Author(s):  
Robert J. Calin-Jageman ◽  
Tracy L. Caldwell
Keyword(s):  
Task Difficulty ◽  
Statistical Power ◽  
Meta Analysis ◽  
A Priori ◽  
Significant Heterogeneity ◽  
Performance Study ◽  
Improve Performance ◽  
Research Designs ◽  
Series Of Experiments ◽  
And Performance

A recent series of experiments suggests that fostering superstitions can substantially improve performance on a variety of motor and cognitive tasks ( Damisch, Stoberock, & Mussweiler, 2010 ). We conducted two high-powered and precise replications of one of these experiments, examining if telling participants they had a lucky golf ball could improve their performance on a 10-shot golf task relative to controls. We found that the effect of superstition on performance is elusive: Participants told they had a lucky ball performed almost identically to controls. Our failure to replicate the target study was not due to lack of impact, lack of statistical power, differences in task difficulty, nor differences in participant belief in luck. A meta-analysis indicates significant heterogeneity in the effect of superstition on performance. This could be due to an unknown moderator, but no effect was observed among the studies with the strongest research designs (e.g., high power, a priori sampling plan).

ELIXIR TO EXAMINATION STRESS AMONG STUDENT - STUDY SKILLS TRAINING AND SYSTEMATIC DESENSITIZATION

2018 ◽  
Vol 6 (26) ◽  
Author(s):  
Jyoti Baijal
Keyword(s):  
Study Skills ◽  
Knowledge Society ◽  
Skills Training ◽  
Well Being ◽  
Systematic Desensitization ◽  
Performance Study ◽  
High Stakes ◽  
Deficit Model ◽  
Examination Stress ◽  
And Performance

Examination stress is a ubiquitous phenomenon that has, in the present times, adversely affected the learning outcomes and performance of the students at all levels- primary, secondary or higher education. It’s increasing intensity specifically among students appearing for high stakes board examination evokes a response from the teaching fraternity at the earliest. The reason being that a prolonged experience of stress with respect to evaluative situations is bound to prove detrimental to the mental, physical and emotional well-being of the students. For the nation to develop and progress towards a knowledge society, it is imperative that the students are taught to cope with stressful stimuli and improve performance. Study-Skills Training is an intervention intended to improve their study and test- taking habits and skills. It is based on a cognitive-deficit model which is directed towards improving a variety of cognitive activities that affect the organization, processing and retrieval of information and thereby help in reducing the experience of examination stress. Systematic desensitization as a process can be used to unlearn anxiety reactions by replacing the anxiety response with a calm, relaxed state. Thus, a combination of study-skills training and systematic desensitization has been shown to be effective and superior in alleviating test anxiety

scholarly journals Development and performance study of a natural silk fiber facial mask paper

2020 ◽  
Vol 15 ◽  
pp. 155892502097575
Author(s):  
Huiling Wang ◽  
Bin Zhou
Keyword(s):  
Silk Fiber ◽  
Entrainment Rate ◽  
Performance Study ◽  
Wet Strength ◽  
Facial Mask ◽  
Antibacterial Performance ◽  
Lower Elongation ◽  
The Common ◽  
And Performance ◽  
Acid Structure

Facial masks are beauty products which composed of a facial mask paper and beauty solution. Silk contains the amino acid structure closest to the human skin, and has the skin-friendly, cosmetic and antibacterial functions, but the common method for making nonwoven facial mask paper is not suitable for silk. In this paper, the silkworm’s spinning path is intervened manually to obtain a smart silk facial mask paper (SMC) of controllable thickness, so that the sericin on the silk fiber is well preserved. In the experiment where the SMC is compared with the nonwoven 384-cuprammonium rayon facial mask paper (CRMC) which is the most widely used in the market, it is found that the ways of forming the two facial mask paper are completely different, and therefore the morphologies under SEM are obviously different. The thickness of the SMC is 0.183 mm and the areal weight of it is 38.0 g/m2. It is very close to the CRMC (0.187 mm, 38.4 g/m2). The porosity of the SMC is 84.0%, which is slightly lower than that of the CRMC (86.3%), but its pores are well distributed. Compared with the CRMC, the smart SMC has higher dry and wet strength, lower elongation, slightly lower air permeability and liquid entrainment rate, and better antibacterial performance.

scholarly journals Design and Performance Study for Electrothermally Deep-Sea Drive Microunits Using a Paraffin Phase Change Material

Micromachines ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 415
Author(s):  
Dayong Ning ◽  
Zihao Li ◽  
Gangda Liang ◽  
Qibo Wang ◽  
Weifeng Zou ◽  
...  
Keyword(s):  
Phase Change ◽  
Phase Change Material ◽  
Deep Sea ◽  
Hydraulic System ◽  
Functional Verification ◽  
Performance Study ◽  
Micro Electro Mechanical Systems ◽  
Pressure Compensation ◽  
And Performance ◽  
Change Material

Considering the further exploration of the ocean, the requirements for deep-sea operation equipment have increased. Many problems existing in the widely used deep-sea hydraulic system have become increasingly prominent. Compared with the traditional deep-sea hydraulic system, actuators using a paraffin phase change material (PCM) have incomparable advantages, including lightweight structure, low energy consumption, high adaptability to the deep sea, and good biocompatibility. Thus, a deep-sea drive microunit (DDM) based on paraffin PCM is proposed in this paper. The device adopts a flexible shell, adapting to the high-pressure environment of the deep-sea based on the principle of pressure compensation. The device realizes the output of displacement and force through the electrothermal drive, which can be used as actuator or power source of other underwater operation equipment. The microunit successfully completes the functional verification experiments in air, shallow water, and hydrostatic pressure of 110 MPa. In accordance with experimental results, a reasonable control curve is fitted, highlighting its potential application in deep-sea micro electro mechanical systems, especially in underwater soft robot.

scholarly journals A Revisit to CMFD Schemes: Fourier Analysis and Enhancement

Energies ◽  
2021 ◽  
Vol 14 (2) ◽  
pp. 424
Author(s):  
Dean Wang ◽  
Zuolong Zhu
Keyword(s):  
Fourier Analysis ◽  
Eigenvalue Problems ◽  
Neutron Transport ◽  
Coarse Mesh ◽  
Successive Overrelaxation ◽  
Computational Cell ◽  
Artificial Diffusion ◽  
Acceleration Method ◽  
The Stability ◽  
Partial Current

The coarse-mesh finite difference (CMFD) scheme is a very effective nonlinear diffusion acceleration method for neutron transport calculations. CMFD can become unstable and fail to converge when the computational cell optical thickness is relatively large in k-eigenvalue problems or diffusive fixed-source problems. Some variants and fixups have been developed to enhance the stability of CMFD, including the partial current-based CMFD (pCMFD), optimally diffusive CMFD (odCMFD), and linear prolongation-based CMFD (lpCMFD). Linearized Fourier analysis has proven to be a very reliable and accurate tool to investigate the convergence rate and stability of such coupled high-order transport/low-order diffusion iterative schemes. It is shown in this paper that the use of different transport solvers in Fourier analysis may have some potential implications on the development of stabilizing techniques, which is exemplified by the odCMFD scheme. A modification to the artificial diffusion coefficients of odCMFD is proposed to improve its stability. In addition, two explicit expressions are presented to calculate local optimal successive overrelaxation (SOR) factors for lpCMFD to further enhance its acceleration performance for fixed-source problems and k-eigenvalue problems, respectively.

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