Determination of optimal transient in the anti-surge control system of the gas compressor unit

This study aims to find out how the application of internal control over inventory of goods at PT Mica Jaya Pratama Solo. This research is a qualitative research that is by conducting both structured and unstructured interviews to determine the internal control carried out by the company. In this study the variables are the principles of internal control such as adequate separation of duties (organizational structure), determination of adequate responsibilities (system of authority), design and use of documents and adequate records (healthy practices), physical control of assets and records adequate (healthy practice), independently verify performance (HR). The result of this study is that the inventory control system at PT. Mica Jaya Pratama is in accordance with the SOP, but in an adequate separation of duties there is no division between the purchasing division and the finance division.

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Discussion on Anti-surge Control System of Centrifugal Compressor

10.47939/et.v2i6.50 ◽

2021 ◽

Keyword(s):

Control System ◽

Centrifugal Compressor ◽

Surge Control

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Design and kinematics of a 3-D printed walking robot “Big Foot”, overcoming obstacles

International Journal of Advanced Robotic Systems ◽

10.1177/1729881419891329 ◽

2019 ◽

Vol 16 (6) ◽

pp. 172988141989132

Author(s):

Ivan Chavdarov ◽

Bozhidar Naydenov

Keyword(s):

Control System ◽

Walking Robots ◽

Energy Losses ◽

Simple Design ◽

Walking Robot ◽

Minimum Number ◽

And Control ◽

Original Concept ◽

Dimensional Optimization

The proposed study presents an original concept for the design of a walking robot with a minimum number of motors. The robot has a simple design and control system, successfully moves by walking, avoids or overcomes obstacles using only two independently controlled motors. Described are basic geometric and kinematic dependencies related to its movement. It is proposed optimization of basic dimensions of the robot in order to reduce energy losses when moving on flat terrain. Developed and produced is a 3-D printed prototype of the robot. Simulation and experiments for overcoming an obstacle are presented. Trajectories and instantaneous velocities centers of links from the robot are experimentally determined. The phases of walking and the stages of overcoming an obstacle are described. The theoretical and experimental results are compared. The suggested dimensional optimization approaches to reduce energy loss and experimental determination of the instant center of rotation are also applicable to other walking robots.

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Predictive Surge Control and Optimization for a Centrifugal Compressor

Journal of Turbomachinery ◽

10.1115/1.3262028 ◽

1986 ◽

Vol 108 (1) ◽

pp. 82-89 ◽

Cited By ~ 2

Author(s):

D. Patlovany ◽

A. B. Focke

Keyword(s):

Control System ◽

Supervisory Control ◽

Control Method ◽

Energy Costs ◽

Operating Region ◽

Stable Operating ◽

Performance Map ◽

Surge Control ◽

Compressor Performance ◽

Supervisory Control System

This paper details the installation of a retrofit supervisory control system on a large air compressor for the purpose of minimizing energy costs and protecting the compressor from surge. The paper discusses how an accurate prediction of the compressor’s stable operating region can be calculated to develop a compressor performance “map” and how this map can then be used to cut energy consumption by the compressor driver. The compressor is protected from surging by a “predictive” control method. Instead of waiting for the compressor to surge, and then reacting, the system calculates when surge is about to occur and takes action to avoid a surge event before it occurs. The installation of a control system of this type can result in a substantial dollar savings in energy costs, while guaranteeing that a compressor will be protected from any damage from a severe surge event. This system has been installed in our plant and proven in practice. The paper details the installation of this system and its results.

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On Uniqueness of Filippov’s Solutions for Non-Smooth Systems Having Multiple Discontinuity Surfaces With Applications to Control Engineering

Dynamic Systems and Control, Parts A and B ◽

10.1115/imece2004-59824 ◽

2004 ◽

Author(s):

Qiong Wu ◽

Hairong Zeng ◽

Nariman Sepehri

Keyword(s):

Control System ◽

State Space ◽

Control Systems ◽

Convex Sets ◽

Discontinuity Surface ◽

Control Engineering ◽

Smooth Control ◽

Discontinuity Surfaces ◽

Uniqueness Of The Solution

The analysis of the uniqueness of Filippov’s solutions to non-smooth control systems is important before the solutions can be sought. Such an analysis is extremely challenging when the discontinuity surface is the intersecting discontinuity surfaces. The key step is to study the intersections of the convex sets from Filippov’s inclusions and the sets containing vectors tangent to the discontinuity surfaces. Due to the fact that all the elements of these sets are functions of the states and time and their numerical values can not be obtained before the uniqueness of the solution is analyzed, the determination of such intersections, symbolically, is extremely difficult. In this paper, we propose to firstly transform the control system to a new state space where the discontinuity surfaces can be written in special forms. Secondly, we expand the sets associated with Filippov’s inclusion such that the determinations of the intersections become feasible. Two examples of practical non-smooth control systems are presented to demonstrate the efficacy of the method.

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Pengaruh Integritas dan Moralitas Individu pada Kecurangan Akuntansi dengan Sistem Pengendalian Internal sebagai Variabel Mediasi

E-Jurnal Akuntansi ◽

10.24843/eja.2020.v30.i09.p10 ◽

2020 ◽

Vol 30 (9) ◽

pp. 2296

Author(s):

I Kadek Yogi Anggara ◽

Herkulanus Bambang Suprasto

Keyword(s):

Control System ◽

Control Systems ◽

Internal Control ◽

Accounting Fraud ◽

Regional Organizations ◽

Purposive Sampling ◽

Internal Control System ◽

Negative Effect ◽

Positive Effect

This study aims to determine the effect of integrity and morality of individuals on accounting fraud with internal control systems as a mediating variable. The population in this study are 37 Regional Organizations in Badung. Determination of the sample using purposive sampling with 74 respondents. The results showed that individual integrity and morality had a negative effect on accounting fraud, integrity and morality of individuals had a positive effect on the internal control system and the internal control system had a negative effect on accounting fraud. Internal control system partially mediates the negative effect of Integrity on accounting fraud. Internal control system does not mediate the negative effect of Individual Morality on Accounting Fraud. The results are expected to be able to provide insight for relevant parties to pay more attention to internal control systems because they can influence mediating integrity against accounting fraud. Keywords: Cheating; Aaccounting Fraud; Regional Organizations.

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