scholarly journals Improving the Stability of α-CsPbI3 Nanocrystals in Extreme Conditions Facilitated by Mn2+ Doping

ACS Omega ◽  
2021 ◽  
Author(s):  
Yu Ji ◽  
Jian-Bin Zhang ◽  
Hao-Ran Shen ◽  
Zhan Su ◽  
Hao Cui ◽  
...  
Keyword(s):  
Extreme Conditions ◽  
The Stability

scholarly journals The segmental subsidence structure with immediate roof of gob side entry retaining in backfill mining

2021 ◽  
pp. 014459872199654
Author(s):  
Xin-yuan Zhao ◽  
Xin-wang Li ◽  
Ke Yang ◽  
Zhen Wei ◽  
Qiang Fu
Keyword(s):  
Mechanical Model ◽  
Surrounding Rock ◽  
Extreme Conditions ◽  
Structure Characteristics ◽  
Rock Structure ◽  
Immediate Roof ◽  
Backfill Mining ◽  
The Difference ◽  
The Stability ◽  
Supporting Force

When gob side entry retaining is carried out in backfill mining, the roof will show different subsidence morphology due to the difference of compactness and supporting force of the backfill body at different positions. This paper analyzed the immediate roof subsidence structure under two extreme conditions, constructed the roof segmented subsidence structure and the mechanical model of roadside backfill body, and used FLAC3D software to investigate the roof migration and the force law of the roadside backfill body under the conditions of different goaf backfilled rates, different width and strength of roadside backfill body. Finally, the backfill practice of a mine in Shandong Province of China is taken as an example for analysis. The results show that the segmented subsidence structure of the immediate roof is related to the mechanical properties of the roadside backfill body and the goaf backfill body. When the backfilled rate of goaf decreases from 95% to 70%, the width of roadside backfill body decreases from 5 m to 1 m, and the elastic modulus decreases from 10 GPa to 0.5 GPa, the greater difference in the subsidence and inclination of the immediate roof on both sides of the roadside backfill body is, the more obvious the segmented subsidence structure characteristics of the immediate roof are, and the greater force on the roadside backfill body will be, the more unfavorable it is to maintain the stability of the roadway surrounding rock and the roadway backfill body. Therefore, when gob side entry retaining is carried out in backfill mining, the surrounding rock structure and the force on roadside backfill body should be considered comprehensively.

scholarly journals PENGATURAN SUDUT AZIMUTH ROKET RUM UNTUK OPERASI PELUNCURAN PADA KECEPATAN ANGIN DI ATAS 10 KNOT

2016 ◽  
Vol 14 (1) ◽  
pp. 9
Author(s):  
Heri Budi Wibowo ◽  
Ahmad Riyadl ◽  
Yudha Agung Nugroho
Keyword(s):  
Wind Speed ◽  
Wind Direction ◽  
Azimuth Angle ◽  
Rocket Motor ◽  
Extreme Conditions ◽  
Wind Speeds ◽  
Flight Direction ◽  
Maximum Payload ◽  
Left And Right ◽  
The Stability

RUM rocket is a rocket used in the payload competition among university students. The rocket is designed to bring a maximum payload of 1 kg to altitude of 600-1000 m and  falls safely on a 500 m radius of the left and right rear of the center point of the launching pad of the conditions of wind speeds below 10 knots. In extreme circumstances where the wind speed is above 10 knots, the effect of speed and direction of wind to the stability of the rocket flight direction large enough  to cause it to fall beyond the defined safety radius. The research aims to adjust azimuth setting of the rocket so that the fall of  the rocket motor remains secure within the radius of the launch area. The study was conducted by testing a rocket RUM in extreme conditions (wind speed of 10-20 knots) with variations in shear-pin and azimuth angle. The test variables are the position of the fallen rocket motor. The results show that the wind direction and speed significantly affecting direction of rockets flight. The results show that rocket azimuth angle of 60 degrees with the direction of 90 degrees from the wind direction can make thea rocket falls on a secure area (within 500 m). Abstrak Roket RUM adalah roket untuk lomba muatan antar mahasiswa. Roket didisain membawa beban maksimum 1 kg dengan ketinggian 600-1000 m dan jatuh pada radius 500 m dari titik pusat peluncuran dengan kondisi kecepatan angin di bawah 10 knot. Dalam keadaan ekstrim dimana kecepatan angin di atas 10 knot, pengaruh kecepatan angin terhadap arah terbang roket menjadi besar sehingga dapat menyebabkan jatuhnya roket meleset di luar radius aman yang telah diitetapkan. Penelitian ini bertujuan mengatur sudut azimuth roket untuk mengatur jatuhnya motor roket sehingga tetap aman dalam radius area peluncuran. Penelitian dilakukan dengan melakukan pengujian roket RUM pada kondisi ekstrim (kecepatan angin 10-20 knot) dengan variasi penahan beban dan sudut azimuth. Hasil optimasi menunjukkan bahwa dengan menggunakan penahan beban dan pengaturan sudut azimuth roket 60 derajat dengan arah 90 derajat dari arah angin dapat membuat roket jatuh pada daerah aman peluncuran (500 m).

scholarly journals Extremophile – An Adaptive Strategy for Extreme Conditions and Applications

2020 ◽  
Vol 21 (2) ◽  
pp. 96-110 ◽  
Author(s):  
Isha Kohli ◽  
Naveen C. Joshi ◽  
Swati Mohapatra ◽  
Ajit Varma
Keyword(s):  
Molecular Mechanisms ◽  
Adaptive Strategy ◽  
Temperature Tolerance ◽  
Extreme Conditions ◽  
Structural Genomic ◽  
Genomic Features ◽  
The Stability ◽  
Harsh Conditions ◽  
Enhanced Stability ◽  
Extremes Of Temperature

The concurrence of microorganisms in niches that are hostile like extremes of temperature, pH, salt concentration and high pressure depends upon novel molecular mechanisms to enhance the stability of their proteins, nucleic acids, lipids and cell membranes. The structural, physiological and genomic features of extremophiles that make them capable of withstanding extremely selective environmental conditions are particularly fascinating. Highly stable enzymes exhibiting several industrial and biotechnological properties are being isolated and purified from these extremophiles. Successful gene cloning of the purified extremozymes in the mesophilic hosts has already been done. Various extremozymes such as amylase, lipase, xylanase, cellulase and protease from thermophiles, halothermophiles and psychrophiles are of industrial interests due to their enhanced stability at forbidding conditions. In this review, we made an attempt to point out the unique features of extremophiles, particularly thermophiles and psychrophiles, at the structural, genomic and proteomic levels, which allow for functionality at harsh conditions focusing on the temperature tolerance by them.

Stability control of in-wheel motor electric vehicles under extreme conditions

2018 ◽  
Vol 41 (10) ◽  
pp. 2838-2850 ◽  
Author(s):  
Zijun Zhang ◽  
Wanzhong Zhao ◽  
Chunyan Wang ◽  
Liang Li
Keyword(s):  
Electric Vehicles ◽  
Control Strategy ◽  
Lower Layer ◽  
Stability Control ◽  
Extreme Conditions ◽  
Initial Values ◽  
Yaw Moment Control ◽  
Nonlinear Vehicle Model ◽  
The Stability ◽  
Three Degree Of Freedom

To investigate the stability of in-wheel motor electric vehicles (IWMEVs) under extreme conditions, a novel control strategy including active rear steering (ARS) mode and direct yaw moment control (DYC) mode is proposed in this paper, utilizing the adaptive dynamic neural network (ADNN) algorithm to make the most of the two control modes. Firstly, a three-degree of freedom nonlinear vehicle model as well as some subsystems is established. Then, a two-layer stability control strategy is put forward, where the upper-layer calculates the desired rear steering angle as well as the differential torque of the rear wheels and the lower-layer executes commands and returns relevant signals. Besides, a stability controller based on ADNN algorithm is designed in the upper-layer so as to take advantage of the two modes under extreme conditions. Next, the impacts of initial values of the connection weights on the ability of ADNN algorithm to train and learn are revealed. Consequently, the optimal initial values can be ascertained before the following simulations. Finally, the closed loop simulations of ARS and DYC are carried out under some extreme conditions such as high velocity and low adhesion coefficient roads, and the results indicate that compared with DYC’s difficulty in playing its role, ARS mode can significantly improve the stability of IWMEVs even under extreme conditions.

scholarly journals Improved Stabilization for Robust Fixed Point Transformations-Based Controllers

2013 ◽  
Vol 17 (3) ◽  
pp. 418-424 ◽  
Author(s):  
Teréz A. Várkonyi ◽  
◽  
József K. Tar ◽  
Imre J. Rudas ◽  
◽  
...  
Keyword(s):  
Fixed Point ◽  
Dynamical Systems ◽  
Approximate Model ◽  
Extreme Conditions ◽  
Recent Past ◽  
Point Transformations ◽  
The Stability

Nowadays, dynamical systems are getting increasingly complex because they have to fulfill more expectations and further they have to handle more and more uncertainties. The controllers built in these systems have to face with the same difficulties. Luckily, the applied new controllers are designed to take into account the grown claims and they are able to fit the extreme conditions. The method called Robust Fixed Point Transformations (RFPT) is used to ameliorate existing controllers’ results when an approximate model is used to predict the dynamical system’s behavior. To achieve the stability of RFPT many efforts have been taken in the recent past. In this paper, a new algorithm is proposed that prevents the occurrence of short temporal unstable periods of the RFPT-based controllers, i.e., ensures the continuous stability.

scholarly journals Fungal Biomarkers Stability in Mars Regolith Analogues after Simulated Space and Mars-like Conditions

2021 ◽  
Vol 7 (10) ◽  
pp. 859
Author(s):  
Alessia Cassaro ◽  
Claudia Pacelli ◽  
Mickael Baqué ◽  
Jean-Pierre Paul de Vera ◽  
Ute Böttger ◽  
...  
Keyword(s):  
Mass Spectrometry ◽  
Gas Chromatography ◽  
Solar System ◽  
High Resistance ◽  
Gas Chromatography Mass Spectrometry ◽  
Extreme Conditions ◽  
Life On Mars ◽  
Fungal Biomarkers ◽  
The Stability ◽  
Scientific Payload

The discovery of life on other planets and moons in our solar system is one of the most important challenges of this era. The second ExoMars mission will look for traces of extant or extinct life on Mars. The instruments on board the rover will be able to reach samples with eventual biomarkers until 2 m of depth under the planet’s surface. This exploration capacity offers the best chance to detect biomarkers which would be mainly preserved compared to samples on the surface which are directly exposed to harmful environmental conditions. Starting with the studies of the endolithic meristematic black fungus Cryomyces antarcticus, which has proved its high resistance under extreme conditions, we analyzed the stability and the resistance of fungal biomarkers after exposure to simulated space and Mars-like conditions, with Raman and Gas Chromatography–Mass Spectrometry, two of the scientific payload instruments on board the rover.

scholarly journals Wave Runup for Nowshahr Breakwater at Tide and EBB Scenarios

2021 ◽  
Vol 2 (4) ◽  
pp. 10-14
Author(s):  
Farhad Sakhaee
Keyword(s):  
Water Depth ◽  
Wave Energy ◽  
High Strength ◽  
Design Criteria ◽  
Breaking Wave ◽  
Extreme Conditions ◽  
Shore Protection ◽  
Wave Runup ◽  
The Stability ◽  
Runup Height

This study investigates runup design at breakwaters and design criteria under tidal and ebb scenarios for both head and truck of Nowshahr breakwater. First part includes runup height calculations based on shore protection manuals. Based of wave height, frequency, and water depth at the toe runup height has been calculated and Second portion has been dedicated to design of head and truck of Nowshahr port based on Hudson stability formula. Collision of wave and the breakwater head, results in immediate reduction in wave energy. As wave energy propagated gradually decreases when it meets the trunk. The results showed that in both conditions weight of head would be higher than the trunk of breakwater. while, both head and trunk are designed based on high strength materials, but the head has higher degree of importance in terms of design criteria. Hudson formula is responsible for the stability of breakwater structure. Tidal case which considers a non-breaking wave as well as ebb scenario including a breaking wave has been studied to include two extreme conditions occurs to breakwaters. The results showed the higher weight of head is responsible for stability of breakwater at both conditions.

scholarly journals PENGATURAN SUDUT AZIMUTH ROKET RUM UNTUK OPERASI PELUNCURAN PADA KECEPATAN ANGIN DI ATAS 10 KNOT (AZIMUTH ANGLE’S SETTING OF ROCKET RUM FOR LAUNCH OPERATION AT WIND SPEED MORE THAN 10 KNOT)

2018 ◽  
Vol 14 (1) ◽  
pp. 9
Author(s):  
Heri Budi Wibowo ◽  
Ahmad Riyadl ◽  
Yudha Agung Nugroho
Keyword(s):  
Wind Speed ◽  
Wind Direction ◽  
Azimuth Angle ◽  
Rocket Motor ◽  
Extreme Conditions ◽  
Wind Speeds ◽  
Flight Direction ◽  
Maximum Payload ◽  
Left And Right ◽  
The Stability

RUM rocket is a rocket used in the payload competition among university students. The rocket is designed to bring a maximum payload of 1 kg to altitude of 600-1000 m and falls safely on a 500 m radius of the left and right rear of the center point of the launching pad of the conditions of wind speeds below 10 knots. In extreme circumstances where the wind speed is above 10 knots, the effect of speed and direction of wind to the stability of the rocket flight direction large enough to cause it to fall beyond the defined safety radius. The research aims to adjust azimuth setting of the rocket so that the fall of the rocket motor remains secure within the radius of the launch area. The study was conducted by testing a rocket RUM in extreme conditions (wind speed of 10-20 knots) with variations in shear-pin and azimuth angle. The test variables are the position of the fallen rocket motor. The results show that the wind direction and speed significantly affecting direction of rockets flight. The results show that rocket azimuth angle of 60 degrees with the direction of 90 degrees from the wind direction can make thea rocket falls on a secure area (within 500 m). ABSTRAKRoket RUM adalah roket untuk lomba muatan antar mahasiswa. Roket didisain membawa beban maksimum 1 kg dengan ketinggian 600-1000 m dan jatuh pada radius 500 m dari titik pusat peluncuran dengan kondisi kecepatan angin di bawah 10 knot. Dalam keadaan ekstrim dimana kecepatan angin di atas 10 knot, pengaruh kecepatan angin terhadap arah terbang roket menjadi besar sehingga dapat menyebabkan jatuhnya roket meleset di luar radius aman yang telah diitetapkan. Penelitian ini bertujuan mengatur sudut azimuth roket untuk mengatur jatuhnya motor roket sehingga tetap aman dalam radius area peluncuran. Penelitian dilakukan dengan melakukan pengujian roket RUM pada kondisi ekstrim (kecepatan angin 10-20 knot) dengan variasi penahan beban dan sudut azimuth. Hasil optimasi menunjukkan bahwa dengan menggunakan penahan beban dan pengaturan sudut azimuth roket 60 derajat dengan arah 90 derajat dari arah angin dapat membuat roket jatuh pada daerah aman peluncuran (500 m).

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