scholarly journals Creep Parameter Inversion and Long-Term Stability Analysis of Tunnel Based on GP-DE Intelligent Algorithm

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Fengrui Zhang ◽  
Annan Jiang ◽  
Xinping Guo ◽  
Xiurong Yang
Keyword(s):  
Stability Analysis ◽  
Differential Evolution ◽  
Differential Evolution Algorithm ◽  
Inversion Method ◽  
Research Results ◽  
Term Stability ◽  
Long Term Stability ◽  
Gauss Process ◽  
The Stability

Aiming at the creep problem of Banshi Tunnel in Jilin province, the creep laws of rock are analyzed by the creep test, and the Cvsic model describing the creep characteristics of the tunnel is established. To obtain the creep parameters accurately, considering the advantages of Gauss process and differential evolution algorithm, coupling the two methods, a Gauss process-differential evolution intelligent inversion method is proposed. According to on-site monitoring data, the the creep parameters of the tunnel are accurately inverted. On this basis, the stability analysis of the tunnel and the selection of a reasonable construction plan are carried out. The research results show that to ensure the stability of the tunnel, the construction scheme of initial lining + pipe shed + advanced grouting anchor rod should be adopted. The research results have guiding significance for the long-term stability evaluation of the tunnel.

LONG-TERM STABILITY ANALYSIS OF ACOUSTIC ABSORBING BOUNDARY CONDITIONS

2013 ◽  
Vol 23 (11) ◽  
pp. 2129-2154 ◽  
Author(s):  
HÉLÈNE BARUCQ ◽  
JULIEN DIAZ ◽  
VÉRONIQUE DUPRAT
Keyword(s):  
Stability Analysis ◽  
Boundary Conditions ◽  
Absorbing Boundary Conditions ◽  
Computational Domain ◽  
Acoustic Wave Equation ◽  
Absorbing Boundary ◽  
Term Stability ◽  
Long Term Stability ◽  
The Stability

This work deals with the stability analysis of a one-parameter family of Absorbing Boundary Conditions (ABC) that have been derived for the acoustic wave equation. We tackle the problem of long-term stability of the wave field both at the continuous and the numerical levels. We first define a function of energy and show that it is decreasing in time. Its discrete form is also decreasing under a Courant–Friedrichs–Lewy (CFL) condition that does not depend on the ABC. Moreover, the decay rate of the continuous energy can be determined: it is exponential if the computational domain is star-shaped and this property can be illustrated numerically.

Fabrication of Boron Compensated Hydrogenated Amorphous Silicon Films with Significantly Improved Stability Using Plasma Enhanced Chemical Vapor Deposition Technique

1995 ◽  
Vol 377 ◽  
Author(s):  
Mohan K. Bhan
Keyword(s):  
Chemical Vapor ◽  
Short Term ◽  
Term Stability ◽  
Long Term Stability ◽  
Vapor Deposition Technique ◽  
Improved Stability ◽  
Donor Acceptor ◽  
B Doping ◽  
The Stability

ABSTRACTWe have systematically investigated the effects of addition of sub-ppm levels of boron on the stability of a-Si:H films and p-i-n devices, deposited by PE-CVD technique. The films thus produced with appropriate amounts of boron, show a significant improvement in stability, when soaked under both AM 1.5 (short-term) as well as 10×sun (long-term) illumination conditions. The opto-electronic properties of the films are quite respectable It is concluded that boron compensates the native impurities by forming donor-acceptor pairs, which reduces the “fast” defects and hence the initial degradation of the films. It is also speculated that boron may also be improving the short-term stability, by reducing the recombination of light generated electrons and holes, by converting D° into D+ states. The long-term stability appears to get affected by hydrogen dilution which seems to reduce the amount of “slow” defects. As a result of B doping of i-layer, the initial conversion efficiency of the devices decreases. It is presumed that our devices may contain an enhanced level of boron impurity, than expected, making them as worse material and to degrade less.

scholarly journals Long-Term Stability Comparison between an Original and a Generic Version of Piperacillin/Tazobactam in Dextrose 5 % Infusion Polyolefin Bags at 5 ± 3 °C after Microwave Freeze-Thaw Treatment

2018 ◽  
Vol 3 (3) ◽  
pp. 143-151
Author(s):  
Sophie Huvelle ◽  
Marie Godet ◽  
Laurence Galanti ◽  
Mélanie Closset ◽  
Benoît Bihin ◽  
...  
Keyword(s):  
Generic Version ◽  
Generic Product ◽  
Brand Name ◽  
Term Stability ◽  
Long Term Stability ◽  
Ph Values ◽  
Lower Confidence ◽  
The Stability ◽  
Aseptic Conditions

AbstractBackgroundPiperacillin-Tazobactam is frequently infused in hospitals. The use of a generic version was considered after the out of stock of the brand name Tazocin®. The stability of 4 g of Tazocin®in 120 mL of dextrose 5 % (D5) was demonstrated during 35 days at 5 °C ± 3 °C after freezing (−20 °C) and microwave thawing (FMT). The aim of the study was to investigate and compare the long-term stability of Tazocin®and a generic product in the same conditions.MethodsFive polyolefin bags of 4 g of Piperacillin/Tazobactam®Sandoz and 5 bags of 4 g of Tazocin®were prepared under aseptic conditions in 120 mL of D5 and stored 3 months at 20 °C then thawed and stored 58 days at 5 ± 3 °C.Spectrophotometric absorbance at different wavelengths, pH measurement, visual and microscopic observations were also performed.The concentrations were measured by HPLC, at 211 nm for tazobactam and 230 nm for piperacilline.ResultsNo significant change in pH values or optic densities, no crystals were detected. The lower confidence limit at 95 % of the concentration for the solutions remains superior to 90 % of the initial concentration until 58 days of storage at 5 ± 3 °C.ConclusionUnder these conditions, 4 g/120 mL of Piperacillin/Tazobactam®Sandoz or Tazocin®in D5 infusion in polyolefin bags remains stable at least for 58 days at 5 ± 3 °C after FMT

Smart pH Sensor Using Untreated Platinum Sheet Based on Chronopotentiometry and Long-Term Stability Analysis

2019 ◽  
Vol 19 (10) ◽  
pp. 3841-3845 ◽  
Author(s):  
Yizhang Wen ◽  
Yuanfang Mao ◽  
Qionghui Luo ◽  
Xiaoping Wang
Keyword(s):  
Stability Analysis ◽  
Ph Sensor ◽  
Term Stability ◽  
Long Term Stability ◽  
Platinum Sheet

scholarly journals Long-Term Stability of Lorazepam in Sodium Chloride 0.9% Stored at Different Temperatures in Different Containers

2019 ◽  
Vol 55 (3) ◽  
pp. 188-192
Author(s):  
M. L. Colsoul ◽  
A. Breuer ◽  
N. Goderniaux ◽  
J. D. Hecq ◽  
L. Soumoy ◽  
...  
Keyword(s):  
Time Management ◽  
High Performance ◽  
Room Temperature ◽  
Color Change ◽  
Storage Period ◽  
Term Stability ◽  
Long Term Stability ◽  
Glass Bottles ◽  
The Stability

Background and Objective: Infusion containing lorazepam is used by geriatric department to limit anxiety disorders in the elderly. Currently, these infusions are prepared according to demand by the nursing staff, but the preparation in advance in a centralized service could improve quality of preparation and time management. The aim of this study was to investigate the long-term stability of this infusion in polypropylene syringes stored at 5 ± 3°C. Then, results obtained were compared with stability data of lorazepam in syringes stored at room temperature, glass bottles at 5 ± 3°C, and glass bottles at room temperature. Method: Eight syringes and 6 bottles of infusion were prepared by diluting 1 mL lorazepam 4 mg in 23 mL of NaCl 0.9% under aseptic conditions. Five syringes and 3 bottles were stored at 5 ± 3°C and 3 syringes and 3 bottles were stored at room temperature for 30 days. During the storage period, particle appearance or color change were periodically checked by visual and microscope inspection. Turbidity was assessed by measurements of optical density (OD) at 3 wavelengths (350 nm, 410 nm, 550 nm). The stability of pH was also evaluated. The lorazepam concentrations were measured at each time point by high-performance liquid chromatography with ultraviolet detector at 220 nm. Results: Solutions were physically unstable in syringes at 5 ± 3°C after 4 days: crystals and a drop of OD at 350 nm were observed. However, pH was stable. After 2 days, solutions were considered as chemically unstable because a loss of lorazepam concentration higher than 10% was noticed: the lower 1-sided confidence limit at 95% was below 90% of the initial concentration. To assess temperature and polypropylene influence, results were compared with those obtained for syringes at room temperature and bottles at 5 ± 3°C and room temperature. Precipitation, drop of OD at 350 nm, and chemical instability were observed in all conditions. Conclusion: Solutions of lorazepam were unstable after 2 days in syringes at 5 ± 3°C. Preparation in advance appears, therefore, not possible for the clinical use. Storage conditions (temperature and form) do not improve the stability.

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