Rolling Bearing Fault Diagnosis Based on Component Screening Vector Local Characteristic-Scale Decomposition

The fault vibration signal of a bearing has nonstationary and nonlinear characteristics and can be regarded as the combination of multiple amplitude- and frequency-modulation components. The envelope of a single component contains the fault characteristics of a bearing. Local characteristic-scale decomposition (LCD) can decompose the vibration signal into a series of multiple intrinsic scale components. Some components can clearly reflect the running state of a bearing, and fault diagnosis is conducted according to the envelope spectrum. However, the conventional LCD takes a single-channel signal as the research object, which cannot fully reflect the characteristic information of the rotor, and the analysis results based on different channel signals of the same section will be inconsistent. To solve this problem, based on full vector spectrum technology, the homologous dual-channel information is fused. A vector LCD method based on cross-correlation coefficient component selection is given, and a simulation analysis is completed. The effectiveness of the proposed method is verified by simulated signals and experimental signals of a bearing, which provides a method for bearing feature extraction and fault diagnosis.

Uncertainty Analysis of an Optoelectronic Strain Measurement System for Flywheel Rotors

The strain in a fast spinning carbon fiber flywheel rotor is of great interest for condition monitoring, as well as for studying long-term aging effects in the carbon fiber matrix. Optoelectronic strain measurement is a contactless measurement principle where a special reflective pattern is applied to the rotor which is scanned by a stationary optical setup. It does not require any active electronic components on the rotor and is suited for operation in a vacuum. In this paper, the influences of the key parts comprising the optoelectronic strain measurement are analyzed. The influence of each part on the measurement result including the uncertainty is modeled. The total uncertainty, as well as each part’s contribution is calculated. This provides a valuable assessment of requirements for component selection, as well as tolerances of mechanical parts and processes to reach a final target measurement uncertainty or to estimate the uncertainty of a given setup. We have shown that the edge quality of the special reflective pattern has the strongest influence, and how to improve it. Considering all influences, it is possible to measure strain with an uncertainty of less than 1% at a rotation speed of 500Hz.

Systematic Design and Circuit Analysis of Lightning Impulse Voltage Generation on Low-Inductance Loads

The well-known circuit for the generation of lightning impulse voltage (LIV) on low-inductance loads was introduced by Glaninger in 1975, and the circuit component selection was proposed by Feser. However, the circuit and the approach for the component selection have some difficulties for which further adjustment is required for obtaining the waveform parameters according to the standard requirement. In this paper, an extended Glaninger’s circuit with an additional series resistor is proposed. Furthermore, a systematic design and circuit analysis of LIV generation for low-inductance loads are developed. With the help of a circuit simulator, the circuit analysis for the component selection is described. The validity of the proposed circuit was confirmed by some experimental results in comparison with the simulated ones. The proposed circuit and component selection provide not only the generation waveform according to the standard requirement but also other promising performances in terms of the wide inductance load range from 400 μH to 4 mH, a voltage efficiency of over 80%, an overshoot voltage of below 5%, an undershoot voltage of below 40%, and a maximum charging capacitance of 10 μF. From the simulated and experimental results, the proposed circuit and component selection approach is very useful for the LIV tests on low-inductance loads instead of using the conventional approach based on trial and error.

Meningkatkan Kompetensi Pedagogik Guru Kelas dalam Penyusunan RPP Melalui Supervisi Akademik pada SDN Sungai Andai 3 Banjarmasin oleh : Sulis

Professional teachers must have 5 (five) competencies, one of which is the competence of preparing lesson plans. There are several factors that cause teachers to have difficulty in compiling it 1) Teachers do not have a linear educational basis so they are not equipped with knowledge about planning and implementing learning. 2) Teachers have never attended training on RPP preparation so they only copy and paste from their friends, even though, they are not relevant to the situation and conditions in their school so that the existing RPP cannot be used as a reference in the learning process. 3) Teachers have attended training, but have not been able to apply it in schools. One of the programs that can be held in the context of teacher empowerment is academic supervision (academic supervision).This research was conducted in three stages, namely preparation, implementation and evaluation/reflection, and carried out at least in two cycles. This research is aimed at teachers of all subjects who do not have a linear teacher education background totaling 20 people, namely: 16 class teachers, 2 sports teachers, and 2 PAI teachers. In cycle I, this action research involved 5 subject teachers who did not have a teacher education background, who were in this school. The research begins by submitting a self-made lesson plan according to the subjects and competency standards of each to the supervisor. Based on these data, supervisors provide guidance to teachers according to the difficulties of each teacher. In the second cycle, planning activities are based on reflection from cycle 1, while the steps for action and observation activities are the same as in cycle 1 by paying attention to the priority problems concluded in cycle 1 and followed by reflection activities.The results showed, in the components of the formulation of learning objectives indicators, there was an increase from 40% in the initial ability, to 60% in cycle 1 and increased to 70% at the end of the activity. In the Determination Component of learning materials and there is an increase in ability from 65% to 70% after cycle 1 and is stronger to 80%. In the Component Selection of Strategies and learning methods, there was a significant increase from the original 40% to 60% in cycle 1 and increased again to 75% after cycle 2. In the selection of media and learning tools there was also an increase from 60% at the beginning activities and after cycle 1, it becomes 80% after cycle 2. While in terms of planning evaluation of learning. From the original only 40% at the beginning of the activity, to 60% at the end of cycle 1 and managed to reach 70% at the end of cycle 2.Keywords: Academic Supervision, Pedagogic Competency

Design and testing of 1 phase semi-controlled rectifier circuit (experiment scale): a part of green laboratory project

This paper discussed design and testing of one (1) phase semi-controlled full wave rectifier circuit (experiment scale) as a part of green laboratory project. The research method was divided by two stages: design and testing. The design stage included: component selection and calculation, conceptual design and circuit physical implementation. The three main components included 2 diodes, 2 thyristors (SCR), resistive (R) and inductive (L) load with varying values. The testing stage was physical rectifier circuit operation with R (220; 580; 1,500 ohm) and R-L (L=2.37 H) load. The voltage waveform, voltage and current were observed during this stage. The testing results (voltage and current) in rms value were compared with theoretical calculation for validation. The testing results showed that the rectifier circuit working optimally. The testing results were differed by small percentage with theoretical calculation. The output voltage was differed by 1.085%. The output current for R and R-L load were differed by 4.590% and 6.457%, respectively.

Design of Aerodynamic Ball Levitation Laboratory Plant

This paper presents the development of a new Aerodynamic Ball Levitation Laboratory Plant at the Center of Modern Control Techniques and Industrial Informatics (CMCT&II). The entire design process of the plant is described, including the component selection process, the physical construction of the plant, the design of a printed circuit board (PCB) powered by a microcontroller, and the implementation of its firmware. A parametric mathematical model of the laboratory plant is created, whose parameters are then estimated using a nonlinear least-squares method based on acquired experimental data. The Kalman filter and the optimal state-space feedback control are designed based on the obtained mathematical model. The designed controller is then validated using the physical plant.