COMBINATORY APPROACH TO FAILURE FINDING IN PASSENGER CAR ELECTRICAL EQUIPMENT SYSTEM

Maintaining a high level of maintenance of electrical equipment in passenger cars requires research in the field of improving methods and means of technical diagnostics. Electronic devices for automatic control and protection, which are located in the switchboard of the car, are one of the most critical elements in the electrical equipment system, ensuring its reliable, efficient and safe operation. If the automatic adjustment and protection devices are out of regulation during operation, the voltage and current in the electrical equipment network may exceed the permissible level, which leads to the failure of electricity consumers, a battery and a generator. In addition, the semiconductor devices themselves are very sensitive to short-term overloads, in which, even with minor overloads, a breakdown or breakage of the conductive layer occurs. Modern trends in the development of passenger car fleet indicate a sharp increase in the complexity of the element base of cars. This mainly concerns the electrical systems of cars, where all the functions of control, monitoring and diagnostics are performed by electronics. Maintaining a high level of service for such systems requires research in the field of improving methods and means of technical diagnostics. For these purposes, the authors have developed a method for constructing optimal control and diagnostic tests, which is based on a combinatorial approach. The method is easily implemented on a computer.

The Demand Supply Steady-State Process-Based Multi-Level Spare Parts Optimization

Spare parts are one of the important components of the equipment comprehensive support system. Spare parts management plays a decisive role in achieving the desired availability with the minimum cost. With the equipment complexity increasing, the price of spare parts has risen sharply. The traditional spare parts management makes the contradiction between fund shortage and spare parts shortage increasingly prominent. Based on the analysis of the multi-echelon and multi-indenture spare parts support model VARI-METRIC (vary multi-echelon technology for recoverable item control, VARI-METRIC), which is widely used by troops and enterprises in various countries, the model is mainly used in high system availability scenarios. However, in the case of low equipment system availability, the accuracy and cost of model inventory prediction are not ideal. This paper proposed the multi-level spare parts optimization model, which is based on the demand-supply steady-state process. It is an analytical model, which is used to solve the low accuracy problem of the VARI-METRIC model in the low equipment system availability. The analytical model is based on the multi-level spare parts support process. The article deduces methods for solving demand rate, demand–supply rate, equipment system availability, and support system availability. The marginal analysis method is used in the model to analyze the spare parts inventory allocation strategy’s current based cost and availability optimal value. Finally, a simulation model is established to evaluate and verify the model. Then, the simulation results show that, when the low availability of equipment systems are 0.4, 0.6, the relative errors of the analytical model are 3.54%, 3.86%, and its costs are 0.52, 1.795 million ¥ RMB. The experiment proves that the inventory prediction accuracy of the analytical model is significantly higher than that of the VARI-METRIC model in low equipment system availability. Finally, the conclusion and future research directions are discussed.

Semiotika budaya kemaritiman masyarakat Indonesia pada syair lagu

Syair lagu merupakan rangkaian dan tatanan kata indah yang diberi notasi dan dilagukan. Syair lagu memuat simbol-simbol pesan yang hendak disampaikan pencipta kepada pendengarnya. Simbol dalam syair lagu tidak mudah dimengerti dan perlu penafsiran. Pencipta lagu menggunakan simbol verbal pada syair lagu guna mewakili segala hal terkait dengan maksud, harapan, perasaan serta kondisi yang terjadi di lingkungan fisik serta menerjemahkan kehidupan di dunia yang diketahuinya. Untuk memahami sistem tanda yang menggambarkan budaya kemaritiman dalam syair lagu digunakan pendekatan semiotik. Penelitian ini bersifat deskriptif kualitatif, mengkaji bahasa berupa tanda atau simbol dalam syair lagu kemaritiman. Teknik pengumpulan data dengan mendokumentasikan lagu di Museum Musik Indonesia (MMI) di Malang serta eksplorasi di internet. Data berupa aspek kebahasaan yang mengandung sistem tanda budaya kemaritiman dari 14 lagu. Tujuan penelitian mendeskripsikan bentuk penanda dan petanda budaya kemaritiman pada syair lagu dan aspek budaya kemaritiman masyarakat Indonesia. Hasil penelitian ditemukan penanda dan petanda yang menunjukkan budaya kemaritiman pada syair lagu kemaritiman serta empat aspek sistem budaya masyarakat maritim meliputi, sistem mata pencaharian hidup, sistem peralatan hidup dan teknologi, sistem pengetahuan, dan sistem keorganisasian sosial. Lagu-lagu kemaritiman Indonesia merepresentasikan budaya kemaritiman masyarakat pesisir melalui simbol tanda yang ada. Untuk itu, lagu merupakan rekaman budaya masyarakat di masanya. Song verse is a series and arrangement of beautiful words that are noted and performed. The song verse contains symbols of the message that the creator wants to convey to his listener. The symbols in the verse of the song are not easy to understand and need interpretation. The songwriter uses verbal symbols in the song's verse to represent everything related to the intentions, expectations, feelings and conditions that occur in the physical environment and translate life in the world he knows. To understand the sign system that describes maritime culture in song verse, a semiotic approach is used. This research is qualitative descriptive, studying the language in the form of signs or symbols in maritime song verse. Data collection techniques by documenting songs at the Indonesian Music Museum (MMI) in Malang as well as exploration on the internet. Data in the form of language aspects that contain a maritime cultural sign system of 14 songs. The purpose of the study describes the form of markers and signs of maritime culture in song verses and aspects of maritime culture of Indonesian society. The results of the study found markers and signs that show maritime culture in maritime song verses as well as four aspects of the maritime community cultural system including, livelihood system, living equipment system and technology, knowledge system, and social organization system. Indonesian maritime songs represent the maritime culture of coastal communities through the symbol of existing signs. For this reason, the song is a recording of the culture of the people of his time.

A Failure Propagation Analysis Method Based on 3 X 3 Hierarchical Model

In recent years, with the increasing complexity of equipment, system design and safety analysis for the equipment are becoming more and more difficult. In this paper, we make a more comprehensive analysis of the hierarchical relationship of the system from the vertical and horizontal angles and put forward the 3 × 3 Hierarchical Model. Then, we propose a failure propagation analysis method based on 3 × 3 Hierarchical Model. At the same time, SysML is used to build the models, which is convenient for different people to learn and modify the models. Finally, a hydraulic transmission system is taken as an example to illustrate the feasibility of the method.

Contribution Rate Evaluation Method of Equipment System of Systems Based on Fault Tree

In this paper, the terminal air defense equipment system of systems (TADESoS) is studied as an example. The TADESoS is an important part of the joint air defense equipment system of systems, which mainly carries out the combat task to the low altitude flight target. The contribution rate evaluation of the TADESoS can provide theoretical basis for guiding the tactical plan of the TADESoS. Aiming at the problems existing in the evaluation of contribution rate of TADESoS, such as the difficulty of describing the structure of system of systems, the strong subjectivity of the evaluation method, and the difficulty of application of the evaluation results, this paper proposes a method of evaluating the contribution rate of the TADESoS based on fault tree. The method describes the structure of the TADESoS by multiattribute nodes. The probability of the top event is calculated by using the probability of the bottom event. Finally, based on the importance of the bottom event, the contribution rate evaluation model of the TADESoS is established, which solves the existing problems in the current research. Finally, the feasibility of the method is verified by an example.