scholarly journals Analysis on Influence of Hydrogen Content Exceeding Standard in GaAs Device

2022 ◽  
Vol 2160 (1) ◽  
pp. 012006
Author(s):  
Yan Song ◽  
Ping Wen ◽  
Xi Hua ◽  
Zhao Yang ◽  
Tang Xu ◽  
...  
Keyword(s):  
Hydrogen Content ◽  
Engineering Application ◽  
Failure Model ◽  
Protective Measures ◽  
Influence Mechanism

Abstract Aiming at the problem of hydrogen content exceeding the standard in GaAs device, the influence mechanism of hydrogen content exceeding the standard on the device is analyzed, the failure model of hydrogen content exceeding the standard in GaAs device in engineering is given, the source of hydrogen is analyzed, and the protective measures of hydrogen content exceeding the standard are given. It is of certain guiding significance for future engineering application.

Test on Hybrid Connection for Steel Bars in Concrete

2012 ◽  
Vol 166-169 ◽  
pp. 215-218
Author(s):  
Ye Tian ◽  
Peng Feng ◽  
Zheng Hai Zhou ◽  
Lie Ping Ye ◽  
Bao Lin Wan
Keyword(s):  
Mechanical Behavior ◽  
Failure Mechanism ◽  
Ultimate Strength ◽  
Ultimate Load ◽  
Engineering Application ◽  
Labor Cost ◽  
Engineering Practice ◽  
Failure Model ◽  
Steel Bar ◽  
Steel Bars

The steel bar connection is an important and inevitable work in civil engineering. The traditional overlapped connection method usually needs to place the transversal rebars in the overlapped splicing area to restrict the splitting cracks in concrete. The steel usage and labor cost are increased. An improved splice, which is the hybrid connection of welding and overlapping, was developed for mid-diameter bars, which is easy to install and has commendable mechanical behavior. A series of reinforcing rebar splice tests with steel-concrete interaction were conducted. The failure model of hybrid connection and the ultimate strength were acquired. Based on the tests, the failure mechanism of hybrid connections was analyzed. The results show that the ultimate load of the new splice is sufficient for the engineering application and the failure model is reasonable. The hybrid connection could be used in the engineering practice.

Research on Accelerometer Output Error for Rotational Inertial Navigation System

2013 ◽  
Vol 336-338 ◽  
pp. 995-998 ◽  
Author(s):  
Lei Wang ◽  
Wei Wang ◽  
Jian Liu ◽  
Fang Liu
Keyword(s):  
Magnetic Field ◽  
Inertial Navigation ◽  
Engineering Application ◽  
Measurement Unit ◽  
Navigation Systems ◽  
Hop Count ◽  
Differential Signal ◽  
Output Error ◽  
Influence Mechanism ◽  
Slow Drift

In order to restrain the accelerometer output error in rotational inertial navigation systems (INS), the imbalance torque of inertial measurement unit (IMU) and the magnetic field of motor were analyzed based on engineering application. The cause of imbalance torque and its influence mechanism were explained. Method taking plumbum mass to balance the IMU was proposed. The influence mechanism of motors magnetic field on accelerometer output was discussed. Method taking differential signal to communicate was devised. The compared results show the accelerometer output error is decreased effectively after taking these two methods. There is lower noise and no slow drift or hop count in accelerometer output.

The Prediction of Spacecraft Disturbance Starlight Refraction and Navigation Simulation Research

2014 ◽  
Vol 513-517 ◽  
pp. 2687-2693
Author(s):  
Bo Yang ◽  
Wen Hao Lian ◽  
Wen Dong Liu ◽  
Fan Si
Keyword(s):  
Engineering Application ◽  
Star Sensor ◽  
Simulation Research ◽  
Spacecraft Navigation ◽  
Influence Mechanism ◽  
Navigation Simulation ◽  
Forecasting Method ◽  
Spacecraft Orbit ◽  
Simulation Results

The methods of starlight refraction navigation has very strict geometric requirements to starlight refraction direction, in order to capture the refraction of stars accurately, and avoid emerging the serious loss of accuracy of lost star, a forecasting method of interference refractive starlight is proposed in this paper. This method can consider all sorts of bodies under the influence of interference, and predict starlight direction that can happen refraction in the instant position of the corresponding spacecraft, so as to adjust the star sensor posture in advance for quick capture starlight refraction. At the same time, from the geometric relationships researching and analyzing the influence mechanism between refraction stars number and distribution by various interference, the influence of the simulation results show that refraction star distribute on both sides of the spacecraft orbit zonally, its number is closely related to the altitude. While through to accurately forecast on the starlight refraction direction, we can make the spacecraft navigation precision and capture refraction star speed increased by more than one times. Therefore, this paper has important value of engineering application.

A Failure Model for Heterogeneous Nonlinear Anisotropic Geomaterials

2012 ◽  
Vol 594-597 ◽  
pp. 472-481
Author(s):  
Huai Ning Ruan ◽  
Di Wang ◽  
J. W. Ju
Keyword(s):  
Engineering Application ◽  
Failure Criteria ◽  
Biaxial Compression ◽  
Failure Model ◽  
Unconfined Compression ◽  
Anisotropic Behavior ◽  
Proposed Model ◽  
Special Cases ◽  
Earth Structures

In designing earth structures, various kinds of complex soils and rocks are constantly encountered. These geomaterials exhibit heterogeneous, nonlinear, and anisotropic behavior. A failure criterion for such complicated materials is proposed. This model is highly comprehensive. It characterizes heterogeneity, nonlinearity, and anisotropy simultaneously in one equation. Many classical failure criteria employed in geomechanics and plasticity are its special cases. The material parameters in the proposed criterion may be determined from tests of unconfined compression, uniaxial tension, biaxial compression, and direct shear. The case study illustrates the potential of the proposed model in engineering application.

scholarly journals Investigation on the Debonding Failure Model of Anchored Polyurea Coating under a High-Velocity Water Flow and Its Application

2019 ◽  
Vol 11 (5) ◽  
pp. 1261 ◽  
Author(s):  
Bingqi Li ◽  
Zhenyu Zhang ◽  
Xiaogang Wang ◽  
Xiaonan Liu
Keyword(s):  
Elastic Modulus ◽  
High Velocity ◽  
Poisson’S Ratio ◽  
Impact Resistance ◽  
Engineering Application ◽  
Poisson's Ratio ◽  
Zone Model ◽  
Failure Model ◽  
Flood Discharge ◽  
The Impact

The debonding failure of a polymer-based coating seriously affects the safe operation of buildings under the action of a high-velocity flood discharge flow. In order to achieve a healthy and sustainable operation of hydropower stations, the debonding failure between polyurea coating and concrete was described by the cohesive zone model, and a debonding failure model was proposed and verified. The results obtained from the model were basically consistent with the test results. Accordingly, the influence of the performance of different anchoring types, the material mechanics of polyurea-based coating and the bonding on debonding behavior were analyzed, and engineering application research was also carried out. The impact resistances of polyurea-based coating under different anchoring conditions are obtained, which provide a reference for the anti-shock and wear-resistant design of flood discharge infrastructure. The elastic modulus and Poisson’s ratio of the polyurea-based material have a significant influence on the impact resistance of polyurea-based coatings. When the elastic modulus and Poisson’s ratio of a polyurea-based material are 25 MPa and 0.45, respectively, the impact resistance is optimal. The greater the fracture energy of the bonding material, the better the impact resistance. The engineering application results show that the seepage prevention and anti-wear characteristics of flood discharge infrastructure all meet the engineering requirements.

Research and Validation of ICs' TDDB Physics-of-Failure Model

2013 ◽  
Vol 313-314 ◽  
pp. 281-286
Author(s):  
Ming Xu ◽  
Feng Ming Lu ◽  
Chen Hui Zeng
Keyword(s):  
Integrated Circuits ◽  
Test Data ◽  
Semiconductor Device ◽  
Engineering Application ◽  
Test Sample ◽  
Electronic Equipment ◽  
Advanced Technology ◽  
Failure Model ◽  
Physics Of Failure ◽  
Test Verification

In the new era, the reliability technology based on physics of failure (PoF) is playing an increasingly important role in development of electronic equipment. PoF models of electronic products, as the foundation and core of this advanced technology, are the main point of engineering application. With continual scaling of VLSI in electronic equipment, the electric field across gate oxide becomes higher and higher and affects the reliability of semiconductor device greatly. In this paper, TDDB failure mechanism and Physics-of-Failure model was researched firstly. Then the test sample was designed and processed, and the test verification program for TDDB Physics-of-Failure model was carried out to develop the test verification, collect and process test data. Through analyzing test data, the parameters of TDDB model were determined and modified to ensure the Physics-of-Failure model precision and the model could be used in engineering. Based on modified model, the reliability of integrated circuits can be evaluated at designing stage. And the inherent reliability of integrated circuits in electronic equipment could be improved by design optimization to reduce the risk in the process of using.

Uniaxial Ratchetting-Fatigue Interaction of Tempered 42CrMo Steel and its Failure Model

2008 ◽  
Vol 33-37 ◽  
pp. 115-120
Author(s):  
Guo Zheng Kang ◽  
Yu Jie Liu ◽  
Qing Gao
Keyword(s):  
Fatigue Life ◽  
Stress Ratio ◽  
Maximum Stress ◽  
Low Cycle Fatigue ◽  
Engineering Application ◽  
Cyclic Softening ◽  
Failure Model ◽  
Amplitude Maximum ◽  
42Crmo Steel ◽  
Good Agreement

Uniaxial ratchetting-fatigue interaction of tempered 42CrMo alloy steel was observed by various cyclic stressing tests at room temperature. The ratchetting deformation and low cycle fatigue (LCF) property of the material as well as their interaction occurred in cyclic stressing were discussed. It is shown that progressive ratchetting deformation causes the decrease of fatigue life, and the fatigue life of the material depends greatly upon the applied mean stress, stress amplitude, maximum stress and stress ratio. Since tempered 42CrMo steel presents significant cyclic softening feature, a tertiary ratchetting is observed. Based on the experimental results, a simple and reasonable failure model convenient to engineering application was constructed to predict the fatigue life of the material in uniaxial cyclic stressing. The basic variables of the model are maximum stress and stress ratio, and the effect of cyclic softening feature on the ratcheting-fatigue interaction is also included in the model by introducing a new variable. It is shown that the predicted lives are in fairly good agreement with the experimental ones.

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