Optimizing the utilization of scad fish (Decapterus spp.) resource in northern coast of Aceh

For ten years, the Scad fish production in the Northern Coast of Aceh has been increasing rapidly at 172.5%. This condition describes that the Scad fish resource exploitation is implemented under improper management that could encounter an overfishing case. This study aimed to analyze the Scad fish resource utilization level and recommend a management strategy to achieve an optimized Scad fish resource utilization in the Northern Coast of Aceh. This study was performed in the Ocean Fishing Port, Kutaraja, Banda Aceh. Bioeconomic analysis results showed that catching product and effort in MSY condition at 2,838.59 tons and 2,808 trips by economic rent was Rp23,902 million per year. In MEY condition, catching product at 2,748.01 ton with catching effort at 2,311 and economic rent was Rp25,056 million per year. The open-access condition of Scad fish resource with total catching effort at 5,386 trips and economic rent value obtained was Rp 0. Results demonstrated that the Scad fish resource utilization status in the Northern Coast of Aceh encounters biological and economical overfishing. The Scad fish resource management strategy for achieving MSY and MEY condition through input control and output control by establishing the total allowed catching product and catching quota.

Monitoring the structural condition of parts of K 250 centrifugal compressors at different stages of production

Among the existing methods of ensuring the production of goods, an important place is occupied by the input and final quality control of metal products in production. The main task of the input control is to constantly ensure the necessary level of quality, fixed in regulatory documents, by directly checking each batch of supplied metal. The use of active quality control directly during the production of goods allows to prevent and detect defects at the initial stages and during the manufacture of finished types of metal products. Control at the output of the production system has the main purpose to prevent the transfer of defective products to the consumer or to the subsequent technological phases (stages). Goal. The goals is development of methods for monitoring the parts of K-250 centrifugal compressors at various stages of production and selection of the optimal mode of heat treatment of rotor elements made of structural steel of the martensitic class of the 34KHN1MA brand. Method. The control included mechanical tests, metallographic studies of blanks and finished parts, as well as non-destructive testing for internal defects and surface quality. Results. A comprehensive input control of the macro- and microstructure, as well as the mechanical properties of blanks made of 34KHN1MA steel was carried out. A mode of improving the properties of critical parts of a centrifugal compressor made of 34KHN1MA steel by heat treatment is proposed. Control of the finished product was carried out, including mechanical tests, microstructure studies, as well as non-destructive surface quality control.

Nonparametric Method for Predicting the Trajectory of an Actively Maneuvering Vessel for Unmanned Aerial Vehicle Landing

The article is devoted to the development of algorithms for predicting the trajectory of maneuvering objects based on nonparametric systems theory. The analysis of uncertainties affecting the modeling of the movement maneuvering water objects is presented. An overview of parametric, nonparametric and combined methods for predicting maneuvering water objects trajectory is given. The problem of high-precision autonomous control of the landing unmanned aerial vehicles on the landing vessel in the conditions of its irregular movement caused by meteorological conditions and active maneuvering is being solved. The method for predicting the trajectory of a vessel’s movement based on solving direct problems of dynamics using nonparametric systems theory is proposed. The advantages of the proposed method are that it’s not affected by model errors, due to the fact that it is based only on a retrospective analysis of several consecutive values of the spatial vessel coordinates. The proposed method differs from similar nonparametric methods in that it does not require statistical calculations, own training, or time-consuming tuning. The method does not imply the solution of identification model parameters, state and control actions problems and can be applied with any unknown linearizable input control actions, including when the model of the vessel’s motion dynamics is not identifiable. The results of numerical modeling for solution the problem of predicting the trajectory of an actively maneuvering small-sized landing vessel using a full nonlinear dynamic model with six degrees of freedom are presented. The studies carried out confirm the efficiency, adequacy and very fast adjustment of the developed method under conditions of complete parametric and nonparametric uncertainty. The proposed method can be used to predict the trajectory of any vehicle under the condition of linearizability of its model and control signals over the observed time interval.

TESTING IN GOOGLE FORMS AS AN EFFECTIVE MEANS OF DIAGNOSING THE LEVEL OF EDUCATION OF LISTENERS OF QUALIFICATION COURSES

The article focuses on the role of pedagogical testing, which is carried out for the aim of test diagnostics at different stages of learning (initial, in the process of learning the material and its control). It is emphasized that today computer testing is widely used due to the fact that it helps to optimize the educational process and allows you to quickly and objectively perform evaluations with rapid processing of results and the use of feedback technology to build a person-centered learning trajectory. There are a number of benefits to computer testing. The Google Form service, which is often used to create computer tests, is briefly described. For the aim of our research, the results of which are presented in the article, we chose to prove the effectiveness of computer testing created using Google forms at the stage of input control to build a trajectory of the special course and the final - to determine the effectiveness of training. The research method provided using a computer test-questionnaire created with the help of a Google form to conduct a survey of respondents, students of the special course «Media Literacy of a Teacher Philologist», to quickly obtain the necessary information about them to build an effective learning strategy. It is shown that the answers to the computer questionnaire-test before starting the thematic special course give the curator the opportunity to study the target audience of the special course and adjust the learning strategy and identify productive methods of media literacy that will be effective in this special course, specific group. After completing the special course, get factual data on the level of media literacy acquired by students after studying in the special course and prove or disprove the effectiveness of training. Figures of the total indicator of the level of media literacy of teachers of philological disciplines have proved the effectiveness of the use of computer testing in the process of organizing education. It was found that computer tests, created using the service «Google Form», allow the teacher based on the analysis of respondents’ answers to quickly establish the level of education (in our case – the level of media literacy) of students before learning and take it into account when building a personality-oriented trajectory training in a special course, as well as to establish the effectiveness of training on it.

Controlling the PVTOL Aircraft System with an Inverted Pendular Load by means of Nested Saturation Functions and GPI Controller

This paper presents a control scheme that allows height position regulation and stabilization for an unmanned planar vertical takeoff and landing aircraft system with an inverted pendular load. The proposed controller consists of nested saturations and a generalized proportional integral (GPI). The GPI controls the aircraft height and the roll attitude; the latter is used as the fictitious input control. Next, the system is reduced through linear transformations, expressing it as an integrator chain with a nonlinear perturbation. Finally, the nested saturation function-based controller stabilizes the aircraft’s horizontal position and the pendulum’s angle. Obtaining the control approach was a challenging task due to the underactuated nature of the aircraft, particularly ensuring the pendulum’s upright position. The stability analysis was based on the second method of Lyapunov using a simple candidate function. The numerical simulation confirmed the control strategy’s effectiveness and performance. Additionally, the numerical simulation included a comparison against a PD controller, where its corresponding performance indexes were estimated, revealing that our controller had a better response in the presence of unknown disturbances.

Experimental Research of Static Characteristics of Microfluidic Trigger

Experimental research of the main static characteristics of the microfluidic trigger of the 100-micrometer feature size is carried out. In order to research the trigger, the experimental (physical) model has been especially made. As the main result of the research, the transfer and flow-rate characteristics of the trigger are obtained in relation to the two connection schemes: 1) the relay scheme with the two-input control, 2) the comparator scheme with the control at a first input and with a reference setpoint at a second input.