scholarly journals Optimization Design of Actuator Parameters with Stepless Capacity Control System Considering the Effect of Backflow Clearance

2020 ◽  
Vol 10 (8) ◽  
pp. 2703
Author(s):  
Jinjie Zhang ◽  
Chao Zhou ◽  
Zhinong Jiang ◽  
Yao Wang ◽  
Xu Sun
Keyword(s):  
Mathematical Model ◽  
Control System ◽  
Good Effect ◽  
Reciprocating Compressor ◽  
Spring Stiffness ◽  
Objective Functions ◽  
Capacity Control ◽  
Hydraulic Force ◽  
The Impact ◽  
The Relationship

The actuator is the key to the stepless capacity control system of a reciprocating compressor. The coupling effect between the actuator and the reciprocating compressor was not considered in the traditional design, and the large design margin led to low system reliability, high cost and low safety. In this paper, a reciprocating compressor and actuator were taken as research objects. The backflow clearance of the suction valve was simulated by CFD (computational fluid dynamics), The relationship between backflow clearance and resultant gas force of the valve plate was discussed. By building a mathematical model of actuators considering backflow clearance and impact rebound, the relationship between the parameters of actuators was studied. Based on the mathematical model and CFD analysis, the hydraulic force and spring stiffness were taken as the design variables, the impact velocity of ejection or withdrawal and the backflow clearance were taken as objective functions, and the actuator parameters were optimized with NSGA-II (Non-dominated Sorting Genetic Algorithm – II). The optimization results show that when the backflow clearance is 0.0065 mm, the hydraulic force is 94.25 N, and the spring stiffness is 11,575.84 N/m, the objective functions are optimized, the parameters are significantly improved, and a good effect is achieved on the experimental table of a 2D reciprocating compressor.

scholarly journals Optimization Design of Actuator Parameters in Multistage Reciprocating Compressor Stepless Capacity Control System Based on NSGA-II

2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Zhinong Jiang ◽  
Chao Zhou ◽  
Yao Wang ◽  
Jinjie Zhang ◽  
Wenhua Liu ◽  
...  
Keyword(s):  
Control System ◽  
Multiobjective Optimization ◽  
Impact Velocity ◽  
Hydraulic System ◽  
Optimization Design ◽  
Reciprocating Compressor ◽  
Spring Stiffness ◽  
Capacity Control ◽  
Nsga Ii ◽  
The Impact

The capacity control system of reciprocating compressor has great significance for the contribution of energy conservation and emission reduction. The parameters of the actuator and hydraulic system within a reciprocating compressor stepless capacity control system play a decisive role in its control accuracy, mechanical reliability, and mechanical security. The actuators and hydraulic system parameters of the same stage are in conflict with each other. Therefore, the actuator and the multistage reciprocating compressor are studied here, specifically through multiobjective optimization using the Nondominated Sorting Genetic Algorithm (NSGA)-II. The multiobjective optimization design was performed on a two-dimensional (2D) reciprocating compressor test bench. When the spring stiffness of the first stage spring was 27358 N m−1, the spring stiffness of the second stage spring was 23315 N m−1, the inlet oil pressure was 296.62 N, the impact velocity of ejection was 0.4215 m s−1, and the total indicated power deviation was 12.05 kW; the objective functions were optimized. Compared with traditional parameters, the inlet oil pressure, spring stiffness, and impact velocity were all reduced. This parameter optimization design lays the foundations for global optimization designs for stepless capacity control systems.

scholarly journals THE INNOVATIVE POTENTIAL OF HUMAN RESOURCES AS A FACTOR IN THE DEVELOPMENT OF THE INNOVATIVE TECHNOLOGIES MARKET IN UKRAINE

2021 ◽  
Vol 23 (1(78)) ◽  
pp. 58-74
Author(s):  
I.V. GRYSHCHENKO ◽  
V.F. GRYSHCHENKO
Keyword(s):  
Mathematical Model ◽  
Human Resources ◽  
Market Development ◽  
Short Term ◽  
Model Calculations ◽  
Innovative Technologies ◽  
Innovation Capacity ◽  
Innovative Potential ◽  
The Impact ◽  
The Relationship

Topicality. The successful operation of an economic entity, in the development of the innovative technologies market, is largely determined by the innovative potential of its human resources - by the people who work for it - their knowledge, talents, and skills. The wrong combination of these elements, lack of employees who have the necessary qualifications, lack of harmony in the relationship between employers and employees can inevitably lead to serious financial and economic problems. Improving the efficiency of the use of the innovative potential of human resources in the development of the innovative technologies market is one of the most urgent tasks for any business entity. The competitive advantages of business entities, financial and economic indicators of their activity, ensuring sustainable development of entrepreneurship in general, are depending on the degree and balance of its use. Aim and tasks. The purpose of the work is to analyze and develop on its basis recommendations for increasing the level of the innovative potential of human resources in the context of the development of the innovative technologies market in Ukraine. Research results. The article analyzes the main structural elements of the innovative potential of human resources and identifies the factors influencing its level in Ukraine. The results of the analysis allowed us to build an economic and mathematical model of the relationship between innovation capacity, as an indicator of the development of the innovative technologies market and components of the innovative potential of human resources in Ukraine. This made it possible to predict the level of innovation capacity as an indicator of the innovative technologies market development in Ukraine in the short term. The obtained results allowed us to identify problems and develop recommendations for increasing the level of the innovative potential of human resources in the context of the innovative technologies market development in Ukraine. Conclusion. Based on the developed economic and mathematical model, calculations were made that characterize the relationship between innovation capacity as an indicator of the innovative technologies market development and components of the innovative potential of human resources in Ukraine. As shown in the calculations, the proposed economic and mathematical model with high accuracy allows to assess the impact of components of the innovative potential of human resources on innovation capacity and identify major obstacles for its development, which made it possible to predict trends in innovation capacity as an indicator of the innovative technologies market development in Ukraine in the short term.

Research on the Relationship between Speed Control System and Electromechanical Oscillations

2015 ◽  
Vol 710 ◽  
pp. 47-52 ◽  
Author(s):  
Ya Qing Zhu ◽  
Min Zhong ◽  
Yu Jia Ma ◽  
Feng Ping Pan ◽  
Ling Ling Shi ◽  
...  
Keyword(s):  
Control System ◽  
Steam Turbine ◽  
Time Constant ◽  
Response Rate ◽  
Speed Control ◽  
Servo Motor ◽  
Speed Control System ◽  
Hydraulic Servo ◽  
The Impact ◽  
The Relationship

The system damping of electric power systems is influenced by factors of many aspects. In this paper, we analyzed the impact of speed control system on the damping of the whole system in consideration of the Pole-Zero Analysis. The result shows that simple speed control would damp the oscillation, while the power-frequency control would excite the oscillation. Furthermore, the effect of steam turbine response rate on the system damping is analyzed. The time constant of hydraulic servo-motor would determine the response rate of the steam turbine, and as a result, an inflection point exists on the curve which describes the relationship between hydraulic servo-motor time constant and system damping. The result demonstrates that the characteristics of system damping can be used in parameter debugging of steam turbine.

Agility and Manoeuvrability as Passive Defence for Armoured Vehicles

1988 ◽  
Vol 202 (1) ◽  
pp. 65-70 ◽  
Author(s):  
E Sher ◽  
S Refael ◽  
D Luria
Keyword(s):  
Mathematical Model ◽  
Control System ◽  
Experimental Results ◽  
Constant Speed ◽  
Fire Control ◽  
Stationary Target ◽  
The Relationship

A mathematical model is presented and applied to investigate the relationship between the automotive performance and manoeuvring of an armoured vehicle and the probability of its being hit by tank gunfire. The model takes into consideration the type of ammunition, the characteristics of the fire control system and the automotive route of the target. Three cases were examined: a stationary target, an accelerating target and a target moving over a winding course at a constant speed. The model has been calibrated to fit a set of experimental results.

Control Design of Foreign Fibers Detecting System Paving Mechanism

2013 ◽  
Vol 846-847 ◽  
pp. 228-232
Author(s):  
Hua Qing Wang ◽  
Jian Cheng Yang ◽  
Kai Yang ◽  
Jian Feng Qin ◽  
Ze Xu Zhou ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Control System ◽  
Control Design ◽  
Line Speed ◽  
On Line ◽  
Working Principle ◽  
The Mathematical Model ◽  
The Relationship

In this paper the working principle of cotton foreign fibers detecting and clearing on line device paving and loosing part is described, and the mathematical model of the relationship between line speed is established, and paving part control system that is suitable for this device has been designed on this basis.

Thermal performance analysis of reciprocating compressor with stepless capacity control system

2013 ◽  
Vol 54 (2) ◽  
pp. 380-386 ◽  
Author(s):  
Tang Bin ◽  
Zhao Yuanyang ◽  
Li Liansheng ◽  
Liu Guangbin ◽  
Wang Le ◽  
...  
Keyword(s):  
Control System ◽  
Performance Analysis ◽  
Thermal Performance ◽  
Reciprocating Compressor ◽  
Capacity Control

scholarly journals The Impact of a Procurement Implementation and Government Internal Control System on Goods/Services Procurement Fraud Prevention by Using Organization Ethical Culture as a Moderating Variable

2019 ◽  
Vol 15 (1) ◽  
pp. 69-81
Author(s):  
Arasy Ghazali Akbar
Keyword(s):  
Regression Analysis ◽  
Control System ◽  
Internal Control ◽  
Ethical Culture ◽  
Fraud Prevention ◽  
Purposive Sampling ◽  
Goods And Services ◽  
Internal Control System ◽  
The Impact ◽  
The Relationship

Abstract                                                                                     This study aims to empirically examine and prove the organization's ethical culture moderating impact on the relationship between e-procurement implementation and the government's internal control system with fraud prevention in procuring goods and services. Based on the purposive sampling method, 55 obtained samples were analyzed by using moderated regression analysis. The results show several findings, first, implementation of e-procurement has a significant effect on fraud prevention. Second, the government's internal control system has a significant effect on fraud prevention. The third and fourth findings indicate that the organization ethical culture is supported as a moderating variable. Keywords: e-procurement, government’s internal control system, organization ethical culture, fraud preventionPengaruh Implementasi E-Procurement dan Sistem Pengendalian Internal Pemerintah terhadap Pencegahan Fraud Pengadaan Barang/Jasa dengan Budaya Etis Organisasi sebagai PemoderasiAbstrakPenelitian ini bertujuan untuk menguji dan membuktikan secara empiris efek moderasi budaya etis organisasi terhadap hubungan implementasi e-procurement dan sistem pengendalian internal pemerintah dengan pencegahan fraud pengadaan barang dan jasa. Berdasarkan metode purposive sampling diperoleh 10 sampel OPD yang dianalisis dengan menggunakan moderated regression analysis. Hasil menunjukkan beberapa temuan, pertama implementasi e-procurement berpengaruh terhadap pencegahan fraud. Kedua, sistem pengendalian internal pemerintah berpengaruh terhadap pencegahan fraud. Temuan ketiga dan keempat menunjukkan bahwa budaya etis organisasi terdukung sebagai variabel moderasi. Kata Kunci: e-procurement, sistem pengendalian internal pemerintah, budaya etis organisasi, pencegahan fraud.

scholarly journals Building a modification of the SEIRD model of epidemic spread that takes into account the features of COVID-19

2020 ◽  
pp. 14-27
Author(s):  
Нина Игоревна Еремеева
Keyword(s):  
Mathematical Model ◽  
Relative Number ◽  
Rate Of Change ◽  
Distribution Model ◽  
Epidemic Spread ◽  
Infected People ◽  
The Moment ◽  
The Impact ◽  
The Relationship

Статья посвящена построению математической модели SEIIRDm, учитывающей некоторые особенности распространения COVID-19. Представляемая модель построена на основе классической SEIRD-модели распространения эпидемий. В созданной модели, в отличие от базовой, учитывается то, что латентные носители COVID-19 являются в некоторой степени заразными, и что у существенного количества инфицированных болезнь протекает бессимптомно. В SEIIRDm-модели отражен тот факт, что выявленные больные изолируются (госпитализируются) и вероятность заражения от них резко уменьшается, а также, что карантинные меры имеют массовый характер, причем важна как степень их жесткости, так и момент введения. Кроме того, в статье обращается внимание на то, что зависимость между скоростью изменения относительного числа заболевших и относительным количеством заразных и восприимчивых может быть нелинейной, и этот факт отражен в построенной модели. Статья содержит примеры численного прогнозирования развития эпидемиологического процесса, а также моделирования влияния массовых карантинных мер, рассчитанные на основе созданной математической модели. The article is devoted to the construction of a mathematical model that takes into account some features of COVID-19 propagation. The presented model is based on the classic SEIRD epidemic distribution model. The created model, in contrast to the basic one, takes into account the fact that latent COVIND-19 carriers are somewhat contagious and that in a significant number of infected people, the disease is asymptomatic. The SEIIRDm model reflects the fact that identified patients are isolating (hospitalizing) and the probability of infection from them decreases sharply and also that the measures taken over the quarantine are massive moreover, both the degree of their rigidity and the moment of introduction are important. Besides, the article draws attention to the fact that the relationship between the rate of change in the relative number of cases and susceptible and the relative number of infected may be nonlinear, and this fact is reflected in the built model. The article provides examples of numerical forecasting of the development of the epidemiological process as well as modeling the impact of mass quarantine measures, calculated on the basis of the created mathematical model.

scholarly journals Modeling the control processes of the size population of microorganisms using modulated microwave

2021 ◽  
pp. 155-161
Author(s):  
Alexander Oshchepkov
Keyword(s):  
Mathematical Model ◽  
Computer Simulation ◽  
Control System ◽  
Microwave Radiation ◽  
Modulation Frequency ◽  
Dynamic Environment ◽  
Automatic Tuning ◽  
Size Population ◽  
Optimal Values ◽  
The Impact

The paper describes a mathematical model of a control system for the size population of microorganisms using modulated microwave radiation of non-thermal power.The model is implemented in the dynamic environment MATLAB+Simulink, the areas of optimal values of the impact parameters are found. An algorithm for automatic tuning of the modulation frequency during the experiment has been developed.The efficiency of the algorithmis shown with the help of computer simulation.

scholarly journals Aircraft Automatic Control System Failure and Flight Safety

2016 ◽  
Vol 3 (1) ◽  
pp. 15-23
Author(s):  
Mareks Šlihta ◽  
Vladimirs Šestakovs ◽  
Ramachandran Karunanidhi
Keyword(s):  
Mathematical Model ◽  
Control System ◽  
Automatic Control ◽  
Automatic Control System ◽  
Flight Safety ◽  
System Failure ◽  
Equipment Failure ◽  
Successful Completion ◽  
The Relationship

Abstract This article presents a mathematical model estimating the probability of successful completion of the aircraft’s flight in case of aviation equipment failure in flight. This paper shows the relationship between the aircraft’s automatic control system and flight safety. The calculations of probability are made for the successful completion of the flight on Boeing 737 aircraft when the automatic control system has failed.

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