scholarly journals Exploration of grid scheme for Frisch-grid ionization chamber

2021 ◽  
Vol 81 (12) ◽  
Author(s):  
Meng Li ◽  
Yuansheng Yang ◽  
Peng Ma ◽  
Junwei Zhang ◽  
Zhi Qin ◽  
...  
Keyword(s):  
Energy Resolution ◽  
Ionization Chamber ◽  
Simulation Method ◽  
Operating Voltage ◽  
Detector Performance ◽  
Electron Collection ◽  
Grid Scheme ◽  
Grid Selection ◽  
Mesh Grid ◽  
The Relationship

AbstractA new Frisch-grid ionization chamber has been built to explore the appropriate choice of Frisch-grid. Detailed studies of the relationship between grid geometries and detector performance have been performed with an $$^{241}$$ 241 Am source. This paper describes and compares the energy resolution of ionization chambers with parallel-wire and mesh grids of different grid parameters. Some specific recommendations for grid selection are provided based on the data currently available. To obtain optimal energy resolution, the operating voltage of the chamber must satisfy the condition of minimum electron collection on the grid with distinct geometries and parameters, respectively. Since there is no established theory applicable to both types of grids, we have devised a careful simulation procedure incorporating the COMSOL and Garfield++ codes to search for the conditions of the minimum electron collection on the grid. The simulation results fit the experimental data well, suggesting that this simulation method successfully predicts the suitable voltage setting when using a mesh grid or parallel wires grid as the shielding electrode.

scholarly journals The Contribution of Urban Morphology to the Formation of the Microclimate in Compact Urban Cores: A Study in the City Center of Thessaloniki

Urban Science ◽  
2021 ◽  
Vol 5 (2) ◽  
pp. 37
Author(s):  
Georgios-Rafail Kouklis ◽  
Athena Yiannakou
Keyword(s):  
Field Study ◽  
Urban Form ◽  
Simulation Method ◽  
Urban Morphology ◽  
Green Spaces ◽  
City Center ◽  
Outdoor Spaces ◽  
Microclimatic Conditions ◽  
The Relationship ◽  
The City

The purpose of this paper is to investigate the contribution of urban morphology to the formation of microclimatic conditions prevailing within urban outdoor spaces. We studied the compact form of a city and examined, at a detailed, street plan level, elements related to air temperature, urban ventilation, and the individual’s thermal comfort. All elements examined are directly affected by both the urban form and the availability of open and green spaces. The field study took place in a typical compact urban fabric of an old city center, the city center of Thessaloniki, where we investigated the relationship between urban morphology and microclimate. Urban morphology was gauged by examining the detailed street plan, along with the local building patterns. We used a simulation method based on the ENVI-met© software. The findings of the field study highlight the fact that the street layout, the urban canyon, and the open and green spaces in a compact urban form contribute decisively both to the creation of the microclimatic conditions and to the influence of the bioclimatic parameters.

scholarly journals Using Computer Simulation Method to Improve Throughput of Production Systems by Buffers and Workers Allocation

2015 ◽  
Vol 6 (4) ◽  
pp. 60-69 ◽  
Author(s):  
Sławomir Kłos ◽  
Peter Trebuna
Keyword(s):  
Computer Simulation ◽  
Production System ◽  
Production Systems ◽  
Simulation Method ◽  
System Throughput ◽  
Buffer Allocation ◽  
Simulation Experiments ◽  
Buffer Capacities ◽  
The Relationship ◽  
Support Decision Making

Abstract This paper proposes the application of computer simulation methods to support decision making regarding intermediate buffer allocations in a series-parallel production line. The simulation model of the production system is based on a real example of a manufacturing company working in the automotive industry. Simulation experiments were conducted for different allocations of buffer capacities and different numbers of employees. The production system consists of three technological operations with intermediate buffers between each operation. The technological operations are carried out using machines and every machine can be operated by one worker. Multi-work in the production system is available (one operator operates several machines). On the basis of the simulation experiments, the relationship between system throughput, buffer allocation and the number of employees is analyzed. Increasing the buffer capacity results in an increase in the average product lifespan. Therefore, in the article a new index is proposed that includes the throughput of the manufacturing system and product life span. Simulation experiments were performed for different configurations of technological operations.

MEASUREMENT OF THE ENERGIES OF α-PARTICLES

1948 ◽  
Vol 26a (4) ◽  
pp. 243-254 ◽  
Author(s):  
T. E. Cranshaw ◽  
J. A. Harvey
Keyword(s):  
Frequency Distribution ◽  
Ionization Energy ◽  
Ionization Chamber ◽  
Experimental Error ◽  
High Stability ◽  
Energy Curve ◽  
Electron Collection ◽  
Linear Amplifier ◽  
Electronic Pulse ◽  
Α Particles

The energies of the α-particles from weak preparations of several new radioactive substances were measured in a grid ionization chamber filled with argon. The accurately known energies of α-particles from several well known sources were used for calibration. The voltage pulses produced by electron collection from the tracks were amplified in a linear amplifier of high stability and converted into flat-topped pulses. An accurately known voltage was subtracted, and the small residual pulses were further amplified. The frequency distribution of pulse sizes was recorded on an electronic pulse analyzer.The final values of the energies are as follows:92U233, 4.823 ± 0.003; 89Ac225, 5.801 ± 0.010; 87Fr221, 6.298 ± 0.010;85At217, 7.023 ± 0.010; 84Po213, 8.336 ± 0.005; and 94Pu239, 5.159 ± 0.005 Mev.The ionization–energy curve in argon was found to be linear within experimental error for α-particles of energy 5 to 9 Mev. Extrapolation of this line determines an intercept of 85 kev. at zero ionization.

An Analysis of Electric Inertia Simulation Method on the Test Platform of Electric Bicycle Brake Force

2014 ◽  
Vol 989-994 ◽  
pp. 3335-3339
Author(s):  
Zhao Xu Yu ◽  
Hong Bin Yu
Keyword(s):  
Simulation Method ◽  
Electrical Simulation ◽  
Mechanical Simulation ◽  
Test Platform ◽  
Electric Bicycle ◽  
Brake Force ◽  
Braking Process ◽  
The One ◽  
The Relationship ◽  
Better Than

This paper analyzes the electric inertia simulation method deeply. By analyzing the brake torgue in the braking process, this paper makes a conclusion about the relationship between the moter’s torgue in the braking process and the simulation of inertia. The test uses the method of combining the mechanical simulation and electrical simulation. In this method, it invites the test platform of electric bicycle brake force, and realizes the inertia simulation. On the test platform, the results showed: by using the electric inertia simulation, the performance of the system is obviously better than the one on the test platform which using flywheel groups. This method improves the degree of automation on the test platform.

scholarly journals The very forward hadron calorimeter PSD for the future CBM@FAIR experiment

2019 ◽  
Vol 204 ◽  
pp. 11004 ◽  
Author(s):  
V. Mikhaylov ◽  
A. Kugler ◽  
V. Kushpil ◽  
O. Svoboda ◽  
P. Tlustý ◽  
...  
Keyword(s):  
Monte Carlo ◽  
Energy Distribution ◽  
Monte Carlo Simulations ◽  
Energy Resolution ◽  
Heavy Ion ◽  
Detector Performance ◽  
Response Measurement ◽  
Gold Collisions ◽  
The Future ◽  
Radiation Conditions

The Projectile Spectator Detector (PSD) of the CBM experiment at the future FAIR facility is a compensating lead-scintillator calorimeter designed to measure the energy distribution of the forward going projectile nucleons and nuclei fragments (reaction spectators) produced close to the beam rapidity. The detector performance for the centrality and reaction plane determination is reviewed based on Monte-Carlo simulations of gold-gold collisions by means of four different heavy-ion event generators. The PSD energy resolution and the linearity of the response measured at CERN PS for the PSD supermodule consisting of 9 modules are presented. Predictions of the calorimeter radiation conditions at CBM and response measurement of one PSD module equipped with neutron irradiated MPPCs used for the light read out are discussed.

scholarly journals Directional presplit blasting in an innovative no-pillar mining approach

2019 ◽  
Vol 16 (5) ◽  
pp. 875-893 ◽  
Author(s):  
Jinzhu Hu ◽  
Xingyu Zhang ◽  
Yubing Gao ◽  
Zimin Ma ◽  
Xinzeng Xu ◽  
...  
Keyword(s):  
Crack Initiation ◽  
Field Test ◽  
Concentration Factor ◽  
New Technology ◽  
Simulation Method ◽  
Explosion Pressure ◽  
Element Simulation ◽  
Pillar Mining ◽  
The Relationship ◽  
Presplit Blasting

Abstract Directional presplit blasting (DPB) technology for an innovative no-pillar mining approach is introduced. First, a mechanical model is established to analyze crack initiation and coalescence using the new technology. The explosion pressure formula containing tress concentration factor explains the relationship between the quantity of explosives and the crack initiation and coalescence. Subsequently, a dynamic finite element simulation method is used to study the stress and damage evolution process of the blasthole wall in ordinary explosion and DPB. The simulation results indicate that the stress concentration factor is approximately 4c10 for the same quantity of explosives. Finally, a field test was conducted in the Fucheng coal mine of China. Based on the field test, the concept of cracking ability is proposed, the relationship between the quantity of explosives and cracking ability is determined, and the quantity of explosives is divided into four stages that are compatible with the roof rock strength. The results can provide some clinical guidance for application of DPB in other projects of the gob-side entry retaining by roof cutting.

Analysis of Geometric Characteristic of Missile Vertical Launching System Guide Rail

2014 ◽  
Vol 620 ◽  
pp. 123-126
Author(s):  
Ji Chao Yang ◽  
Yun Yang
Keyword(s):  
Geometric Characteristic ◽  
Simulation Method ◽  
Assembly Model ◽  
Guide Rail ◽  
Deviation Angle ◽  
Mathematical Methods ◽  
Relationship Model ◽  
Mathematical Formulas ◽  
Dynamic Simulation Model ◽  
The Relationship

By analyzing the shipboard missile vertical launching system (VLS), we simplified the assembly model and reconstructed it with mathematical methods, established the clearance parameter and deviation angle mathematical formulas. In considering of the assembly errors of guide rail in missile vertical launcher system, we studied assembly clearance parameters effects on the system at first. And then established dynamic simulation model, researched the relationship between assembly clearance parameters and missile launching status. At last, used the above relationship model and conclusions, developed a prototype simulation method, and provided the foundation and guidance for design of missile vertical launching system.

Study on the Relationship of Airbag Effect and Occupant Position

2011 ◽  
Vol 299-300 ◽  
pp. 1279-1282
Author(s):  
Xiu Chunb Wu ◽  
Kun Li ◽  
Bo Wang ◽  
Xue Shenc Su
Keyword(s):  
Computer Simulation ◽  
Traffic Accident ◽  
Simulation Method ◽  
Simulation Test ◽  
Computer Simulation Method ◽  
Simulation Results ◽  
Relationship Of ◽  
The Relationship

Computer simulation method is used to study the relations of airbag effect and occupant position. By changing the position of 50% dummy model to achieve the purpose of changing the position between airbag and occupant, three kinds of simulation test are made, and the simulation results are analyzed and compared. It is shown that between the belted occupant and airbag exists such a position or distance, at which the injury to occupant is the smallest when the traffic accident happens.

Study of High Sensitivity Sensor Based on the Principle of Photoionization

2012 ◽  
Vol 503 ◽  
pp. 188-193 ◽  
Author(s):  
Kun Wang Niu ◽  
Ting Liang ◽  
Fang Yang ◽  
Qing Meng ◽  
Kai Wang ◽  
...  
Keyword(s):  
Bias Voltage ◽  
Signal Intensity ◽  
Ionization Chamber ◽  
Detection Efficiency ◽  
High Sensitivity ◽  
Signal Strength ◽  
Detection Sensitivity ◽  
Weak Signal Detection ◽  
The Relationship

The quality of designing structure and properties of sensor photoionization room，directly determines its weak signal detection sensitivity detection and effecting ionization chamber detection efficiency .The paper experiments on four factors of affect the sensitivity of sensor. The results show that: the signal intensity proportional to the area of the ionization chamber; signal intensity goes up with the increase of bias voltage, and with bias voltage into a square the relationship; signal strength was first increased and then decreased with the growth of the distance between electrodes; signal strength was first increased and then decreased. With the growth of light-driven power.

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