The title of the proposal addresses to the provision of breeding rams and bucks for small ruminant farms and some test stations for practical uses. To provide breeding male animals free from diseases ...is one of the biggest problems of small ruminant farming. Farms that can not find suitable breeding male materials have to use the same rams or bucks for long periods of time and thus the herds have not reached the desired levels in terms of the yield and yield declines are the case. By establishing ram-buck provision and test stations, this problem could be solved to according to the expectations of the breeders to provide qualified rams. The main target in the establishment of these centers is to collect ram or buck candidate male offsprings through pre-selection methods from the farms where the breeders can not keep them in their herds due to economical hardships. After the tests, the selected convenient breeding candidates could be utilized in the breeding herds in natural or artificial insemination methods to meet the need for breeding male materials, where extensive breeding is in use and where recording systems have not yet been launched yet, and towards the roles of the Breeding Sheep and Goat Breeders’ Associations.
The paper presents the results of studies on the analysis of the destructive mechanisms for die inserts used in the first operation of wheel forging process, and the results of laboratory tests ...obtained on specially constructed research position for testing thermal fatigue and abrasive wear. The results of investigations on the die inserts shown that the dominant destructive mechanisms for these tools are thermal fatigue occurring in the initial the exploitation stage and abrasive wear, which occurs later, and is intensified effects of thermo-mechanical fatigue and oxidation. The observed mechanisms resulting from the extreme conditions prevailing in the hot forging process and are caused by cyclic changes in thermal and mechanical loads. In order to better analysis and knowledge of phenomena associated with these mechanisms, the authors built a special research positions allow for a more complete analysis of each of the mechanisms separately under laboratory conditions, which correspond to the industrial forging processes. A comprehensive analysis of the inserts confirmed by tests on laboratory stands, showed the interaction between the thermal fatigue and abrasive wear, combined with the process of oxidation. The results showed that the thermal fatigue and destruction as a result of oxidation, very often occur together with the mechanism of abrasive wear, creating a synergy effect, causing the acceleration, the most visible and “easily measurable” processes abrasive wear.
•Analysis and identification of the destructive mechanisms in different areas of tool.•The laboratory thermal fatigue and abrasive wear test stations which allow to detailed analysis these mechanisms separately.•Practical knowledge for forging-engineers about dies failure and damage.
We have developed algorithms and programs for automated tests of synchronous machines. The programs were made using the LabVIEW development system. They are interrelated and have been combined into ...one software system. An approximation of its characteristics using regression equations of different orders with mean-square rate control is used in the algorithms to determine static parameters. A combined optimizing algorithm that is based on the least squares method and alternating-variable descent method is used to determine dynamic parameters. A new effective and adaptive method of sliding trigonometric interpolation is used to filter out possible noise in measuring channels of voltage and current sensors, while determining the parameters of sinusoidal signals in the stationary modes and dots of envelope curves in the transient modes. To reduce the time needed to obtain static characteristics, the software has a special virtual instrument with a field current control loop with a PID controller that provides desired field forcing. The SMTest software system has been tested using HIL modeling and laboratory test stations. Analysis of test results shows that, even when the acquired signal has a 30% noise level, the calculation error in the determination of parameters does not exceed 6%. The software, when used in stationary or mobile test stations, allows automating the process of obtaining characteristics and determining the main static and dynamic parameters of midand high-power rotor synchronous machines.
A virtual instrument is proposed for determining the frequency, amplitude, and initial phase of sinusoidal signals of voltage and current, as well as the angle of phase shift between the voltage and ...current, that is created in the LabVIEW development environment. Comparative analysis of errors of the proposed instrument and the standard virtual instrument Extract Single Tone Information VI from the LabVIEW package was performed, which has shown that the proposed instrument determines the signal parameters more accurately than the standard one if the signals are exposed to industrial noise and interferences.
Modern radio-relay equipment introduced in the communications system of the Serbian Army is required to have maximum effectiveness, availability and readiness. A contribution to these requirements is ...a new approach and a realization method: technology of maintaining radio-relay devices using the method of technical diagnostics. Technical diagnostics is a scientific and technical discipline that recognizes the technical condition of proper functioning and can efficiently be used for maintaining purposes. The paper shows the application of the method of technical diagnostics through the application of measurements with an A group test station which allows an automated acquisition of all relevant data on the technical condition of a device. Based on measurement results, the maintenance of radio-relay equipment is further carried out.
In this paper is presented implementation of a lightweight supervisory control and data acquisition system for remote test stations as a part of a larger test house in the automotive industry. It is ...necessary to allow remote set up and monitoring of the test stations, which means defining the structure of a system with numerous test stations as endpoints. The test stations are meant to be virtual machines but can be both virtual and physical machines. A communication protocol must be used that enables this within the organization's network, regardless of actual distance and location. The parameters of the test stations to be monitored can be defined according to the needs and purpose. Even when creating your own tool, this function is not unique, i.e. on one test station parameters of operating system resources such as memory usage can be monitored, while on another test station logged-in users or running programs, reported system errors and others must be monitored. Data storage is one of the mandatory functions of this system. This process allows viewing data throughout history and more detailed analysis of events. There are numerous benefits that can be drawn and used from the data stored in the database. It is necessary to pay attention to the data stored as well as the scope and retention throughout history. The correct and secure setup of a database is one of the prerequisites for any serious system that processes data. Appropriate views should be created for users involved in the data monitoring process using all the elements mentioned so far. Creating a visually acceptable and easy-to-use interface that serves the main purpose is the final presentation of the entire system to users. A complete system leads to higher productivity, profitability and better organization of the company. It also allows project managers to better plan the use and occupancy of test stations. At any time, they have insight into the status of individual test stations, their activities and the processes taking place. The system must be designed to be easily expandable and flexible, depending on the number of test cells that need to be changed. Adding new test stations to the network and the communication channel should be quick and easy.
Testing and verification of cards and modules in electronic devices containing multiple sections are critical points in system qualification. Factors such as long test times, large amount of test ...data and complex operational processes are some of the issues that prevent fulfilling of the quality objectives. In this study, a test processes of an electronic power card designed by ASELSAN Inc. were automated. The designed test system were examined. A custom test fixture that is specific to the card was designed. It has pins contacting the test points of the card. The control of test and measurement devices was established by general purpose interface bus (GPIB) and peripheral component interconnect (PCI) communication methods. The test of the card were written C# programming language and National Instruments (NI) TestStand test manager was utilized for the running and reporting of the tests. Voltage, current and waveform measurements were taken with the semi-automatic test system that was designed in this study. Based on the test results, automatic test and manual test were compared in terms of test time and efficiency. It has been seen that the designed semi-automatic test system reduces the test time by approximately 82%. Since the time spent in the test processes increases the production cost of the product at the same rate, the test time was shortened and the cost was saved with the designed test system, thus the loss of workforce was prevented and the efficiency was increased considerably.
The study aimed to design and then build a test station to measure the characteristics of headphones, where the effect of different acoustic materials used for filling the acoustic chamber was ...investigated. The first part of the paper provides a comparative review of existing commercial stations used to measure and determine the characteristics of headphones. The second part of the article presents the concept of the author's station, which was intended to be made using mainly a fast and efficient incremental method. Here, 3D printing was decided upon. Further on, the components of the built test station are described. A method of measurement was developed. Then the measured characteristics were presented, compared, and analyzed.
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