scholarly journals Effect of the Size and Position of a Damping Ditch on the Reduction of the Blasting Vibration

2020 ◽  
Vol 2020 ◽  
pp. 1-15
Author(s):  
Baofu Duan ◽  
Shizhan Shen ◽  
Guoshan Ta ◽  
Kebin Sun ◽  
Wei Hou ◽  
...  
Keyword(s):  
Nuclear Power ◽  
Simulation Software ◽  
Vibration Velocity ◽  
Second Phase ◽  
Blasting Vibration ◽  
Factors Affecting ◽  
Practical Applications ◽  
Vibration Data ◽  
Vibration Attenuation ◽  
Different Depths

The size and position of the damping ditch have a direct impact on the blasting vibration. In order to explore the effect of damping ditches of different sizes and positions, we investigated field blasting in the A3 area of the second phase of the Lufeng Nuclear Power Plant project. The simulation software ANSYS/LS-DYNA was used to simulate the vibration propagation of damping ditches with different depths, widths, and positions. Secondly, the vibration data of the corresponding measuring points were collected and the amplitude reduction was analyzed in different situations. An analysis of the numerical simulation results showed that an increase in the damping ditch width increased the vibration amplitude at the top of the building. The depth and position of the damping ditch were the main factors affecting the damping performance. A regression analysis was conducted using the Sadove equation for vibration velocity. It was found that the regression coefficient of the Sadove equation did not meet the required standards when a damping ditch was present. The vibration attenuation equations were fitted for the top and the base of the building. The results of this study provide reference data for the excavation and arrangement of damping ditches in practical applications.

Dynamic Balance and Vibration Control on Field of the Fan L9DVN272ZV in Lingao Nuclear Power Plant

2013 ◽  
Author(s):  
Xiangxiang Dong ◽  
Zhaojie Li
Keyword(s):  
Power Plant ◽  
Nuclear Power ◽  
Power Plants ◽  
Dynamic Balance ◽  
Dynamic Balancing ◽  
Effective Measure ◽  
Vibration Data ◽  
Vibration Attenuation ◽  
The Subject ◽  
Rotor Mass

Dynamic balancing is an effective measure for adjusting an unbalanced fan rotor mass to within its allowable limits. This is a typically implemented method used in nuclear power plants for resolving fan rotor unbalance conditions. The operating spectrum of L9DVN272ZV has always been the fundamental component of the vibration frequency since finding the fan high vibration. This paper discusses the balance process of the subject fan. The vibration data collected was evaluated to aid in selecting the proper method of vibration attenuation. Ultimately the fan vibration was reduced to within the specified allowable limits.

scholarly journals Blasting Energy Analysis of the Different Cutting Methods

2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Ke Man ◽  
Xiaoli Liu ◽  
Ju Wang ◽  
Xiyong Wang
Keyword(s):  
High Frequency ◽  
Low Frequency ◽  
Vibration Velocity ◽  
Blasting Vibration ◽  
Double Wedge ◽  
Factors Affecting ◽  
Good Utilization ◽  
Smooth Blasting ◽  
Blasting Method ◽  
Parallel Hole

Based on the smooth blasting method, the blasting parameters of the Beishan exploration tunnel have been designed. According to the principle of blasting parameters design, three kinds of cutting methods have been laid out, which are straight parallel hole cutting, single-wedge cutting, and double-wedge cutting. The other parameters such as the borehole number, the detonator segment, and the charge amount of each hole are also designed. Then, the blasting tests under different cutting methods were carried out in the field. The results show that all the three cutting methods can achieve good utilization ratio of blasting holes. The blasting effect of straight parallel hole cutting is good. The rock slag size of single-wedge and double-wedge cutting is uniform, which is beneficial to slag extraction. Moreover, the blasting vibration velocity and blasting energy have been analyzed. It is found that the energy distribution of single-wedge and double-wedge cutting is more uniform, mainly concentrated in the high-frequency part, while the energy of straight parallel hole cutting is more concentrated in the low-frequency part. Among many factors affecting blasting vibration velocity, besides the explosive quantity, it would also be easily influenced by the cutting way. It should be noticed that the blasting method includes numerous blasting parameters, which interact with each other. Those blasting parameters obtained were just limited to the cutting method, and the result and the theoretical knowledge could be applied to the blasting and excavation of the deep geoengineering and the HLW geo-disposal.

scholarly journals Water-Depth-Based Prediction Formula for the Blasting Vibration Velocity of Lighthouse Caused by Underwater Drilling Blasting

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
Wenbin Gu ◽  
Zhenxiong Wang ◽  
Jianqing Liu ◽  
Jinglin Xu ◽  
Xin Liu ◽  
...  
Keyword(s):  
Water Depth ◽  
Main Channel ◽  
Hydraulic Structures ◽  
Vibration Velocity ◽  
Blasting Vibration ◽  
Prediction Errors ◽  
Prediction Formula ◽  
Vibration Data ◽  
Undetermined Coefficient ◽  
Fitting Model

Lighthouses are the most important hydraulic structures that should be protected during underwater drilling blasting. Thus, the effect of blasting vibration on lighthouse should be studied. On the basis of the dimensional analysis, we deduced a revised formula for water depth based on Sodev’s empirical formula and established the linear fitting model. During the underwater reef project in the main channel of Shipu Harbor in the Ningbo–Zhoushan Port, the blasting vibration data of the lighthouse near the underwater blasting area were monitored. The undetermined coefficient, resolvable coefficient, and F value of the two formulas were then obtained. The comparison of the data obtained from the two formulas showed that they can effectively predict the blasting vibration on the lighthouse. The correction formula that considers water depth can obviously reduce prediction errors and accurately predict blasting vibration.

scholarly journals Hydroxyurea—The Good, the Bad and the Ugly

Genes ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 1096
Author(s):  
Marcelina W. Musiałek ◽  
Dorota Rybaczek
Keyword(s):  
Cancer Progression ◽  
Specific Interaction ◽  
Interaction Mechanism ◽  
Myeloproliferative Disorders ◽  
Prolonged Treatment ◽  
Actual State ◽  
Cytotoxic Effects ◽  
Factors Affecting ◽  
Cell Cycles ◽  
Practical Applications

Hydroxyurea (HU) is mostly referred to as an inhibitor of ribonucleotide reductase (RNR) and as the agent that is commonly used to arrest cells in the S-phase of the cycle by inducing replication stress. It is a well-known and widely used drug, one which has proved to be effective in treating chronic myeloproliferative disorders and which is considered a staple agent in sickle anemia therapy and—recently—a promising factor in preventing cognitive decline in Alzheimer’s disease. The reversibility of HU-induced replication inhibition also makes it a common laboratory ingredient used to synchronize cell cycles. On the other hand, prolonged treatment or higher dosage of hydroxyurea causes cell death due to accumulation of DNA damage and oxidative stress. Hydroxyurea treatments are also still far from perfect and it has been suggested that it facilitates skin cancer progression. Also, recent studies have shown that hydroxyurea may affect a larger number of enzymes due to its less specific interaction mechanism, which may contribute to further as-yet unspecified factors affecting cell response. In this review, we examine the actual state of knowledge about hydroxyurea and the mechanisms behind its cytotoxic effects. The practical applications of the recent findings may prove to enhance the already existing use of the drug in new and promising ways.

scholarly journals Experiment and Analysis of Wedge Cutting Angle on Cutting Effect

2020 ◽  
Vol 2020 ◽  
pp. 1-16
Author(s):  
Deqiang Yang ◽  
Xuguang Wang ◽  
Yinjun Wang ◽  
Huaming An ◽  
Zhen Lei
Keyword(s):  
Construction Cost ◽  
Economic Benefits ◽  
Tunneling Rate ◽  
Vibration Velocity ◽  
Utilization Rate ◽  
Engineering Practice ◽  
Blasting Vibration ◽  
Cutting Depth ◽  
Vertical Side ◽  
Cutting Angle

In the process of tunnel excavation, large charge wedge cutting blasting is widely used to improve the effect of cut blasting and speed up the excavation rate, which is tantamount to increasing the construction cost. In order to save economic cost and improve cutting blasting effect, wedge cutting models with five different cutting angles were experimented and studied by using concrete materials on the basis of similarity theory analysis. The relationships among cutting depth, blasting volume, blasting fragment, and cutting angle are studied and deduced by the dimensional analysis method. The polynomial fitting of cutting depth, blasting volume, blasting fragment, and cutting angle is carried out according to the experimental data, and the corresponding fitting formula is obtained. The optimum cutting depth, hole utilization rate, blasting volume, and blasting fragment were obtained when the wedge cutting angle was 67° under the same charge. The values were 1.665 × 10−1 m, 92.5%, 8.390 × 10−3 m3, and 49.07 mm, respectively. With the use of TC4850N type blasting vibration meter, the blasting vibrations on the wedge in four directions are tested and analyzed. The results show that when wedge cutting inclination is 65 degrees, the peak vibration velocity is the minimum and the vibration intensity of the wedge cutting inclined side is generally smaller than that of the vertical side. Considering the cutting depth, blasting volume, blasting fragment, blasting vibration hazard, drilling error, tunneling construction cost, and other factors, the 65°∼69° wedge cutting blasting in engineering practice can improve the blasting tunneling rate and increase economic benefits. The experimental results show that the blasting tunneling rate is increased and the economic benefit is increased with the minimum construction tunneling cost, which has certain engineering significance.

Influences of Tunnel Excavation Blasting Vibration on Surface High-Rise Building

2010 ◽  
Vol 163-167 ◽  
pp. 2613-2617
Author(s):  
Hai Liang Wang ◽  
Tong Wei Gao
Keyword(s):  
Vibration Frequency ◽  
Vertical Vibration ◽  
Frame Structure ◽  
Vibration Monitoring ◽  
Vibration Velocity ◽  
Blasting Vibration ◽  
Road Tunnel ◽  
Concrete Frame ◽  
High Rise ◽  
Order Of Magnitude

According to the 33 floors high building, blasting vibration monitoring had been carried on. The building, along Yunnan road tunnel of Qingdao Cross-harbor Tunnel Guide Line Project, has concrete frame structure. Monitoring data had been analyzed. Results showed that rules of vertical vibration velocity and main vibration frequency have similar relevance. Amplification effect of them was existed on the middle and top of the building. From the 2nd floor of downward ground to ground, the value of them suddenly decreased. Main vibration frequency is in the range of 101~102 order of magnitude.

The Research of Marine Nuclear Power Two Loop Simulation Software Based on the Thermal System Analysis

2014 ◽  
Vol 983 ◽  
pp. 288-291
Author(s):  
Guo Lei Zhang ◽  
Xiang Dong Jin ◽  
Zhan Zhao ◽  
Zhi Jun Shi
Keyword(s):  
Nuclear Power ◽  
System Analysis ◽  
Simulation Analysis ◽  
Simulation Software ◽  
Operating Conditions ◽  
Two Phase ◽  
Design Data ◽  
Software Optimization ◽  
Power Simulation ◽  
Basic Functions

To study of Nuclear power simulation software's basic functions and mathematical model based on thermal analysis. Describes the two-phase flow model of GSE software superiority, as well as the software optimization program .Use of software tools for normal operating conditions of the simulation calculation and analysis of the results. Comparison with design data shows that,the software use in marine nuclear power two loop system simulation analysis field, the accuracy of it is higher.

Collective influence maximization for multiple competing products with an awareness-to-influence model

2021 ◽  
Vol 14 (7) ◽  
pp. 1124-1136
Author(s):  
Dimitris Tsaras ◽  
George Trimponias ◽  
Lefteris Ntaflos ◽  
Dimitris Papadias
Keyword(s):  
Diffusion Processes ◽  
Influence Maximization ◽  
Second Phase ◽  
Social Graph ◽  
Practical Applications ◽  
Influence Model ◽  
Best Response ◽  
The Social ◽  
Game Theoretic ◽  
Collective Influence

Influence maximization (IM) is a fundamental task in social network analysis. Typically, IM aims at selecting a set of seeds for the network that influences the maximum number of individuals. Motivated by practical applications, in this paper we focus on an IM variant, where the owner of multiple competing products wishes to select seeds for each product so that the collective influence across all products is maximized. To capture the competing diffusion processes, we introduce an Awareness-to-Influence (AtI) model. In the first phase, awareness about each product propagates in the social graph unhindered by other competing products. In the second phase, a user adopts the most preferred product among those encountered in the awareness phase. To compute the seed sets, we propose GCW, a game-theoretic framework that views the various products as agents, which compete for influence in the social graph and selfishly select their individual strategy. We show that AtI exhibits monotonicity and submodularity; importantly, GCW is a monotone utility game. This allows us to develop an efficient best-response algorithm, with quality guarantees on the collective utility. Our experimental results suggest that our methods are effective, efficient, and scale well to large social networks.

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