scholarly journals Truncation Error Evaluation Method for Minimal Cut Set-Based Fault Tree Analysis

2005 ◽  
Vol 42 (10) ◽  
pp. 854-860 ◽  
Author(s):  
Jong Soo CHOI ◽  
Nam Zin CHO
Keyword(s):  
Truncation Error ◽  
Evaluation Method ◽  
Fault Tree ◽  
Fault Tree Analysis ◽  
Error Evaluation ◽  
Tree Analysis ◽  
Minimal Cut Set ◽  
Minimal Cut ◽  
Cut Set

An Application of Fault Tree Analysis for Decommissioning of Subsea Flexible Pipeline in Brazil

2019 ◽  
Author(s):  
Rafaela Ramos ◽  
Ilson Pasqualino ◽  
Marcelo Igor L. Souza ◽  
Eduardo Ribeiro Nicolosi
Keyword(s):  
Fault Tree ◽  
Fault Tree Analysis ◽  
Third Order ◽  
Tree Analysis ◽  
First Order ◽  
Minimal Cut Set ◽  
Minimal Cut ◽  
Cut Set ◽  
Subsea Pipelines ◽  
Underwater Structures

Abstract The decommissioning of underwater structures has expanded in recent years, as the number of facilities at the end of their useful lives is increasing and legislation becomes more severe. Unlike the production units which already have their decommissioning plans consolidated, subsea pipelines represent the greatest technological, environmental and financial challenge of this stage. Currently, there are few studies to evaluate failures in the decommissioning of flexible pipelines. In addition, these studies generally use simplified analyses. Therefore, this study aims to elaborate a failure analysis for a Reverse Reeling option, in order to contribute to the decision-making process and reduction of failures. For this, a Fault Tree Analysis will be developed followed by the subsequent elaboration of its minimum cut sets. The main results present a total of 13 first-order minimal cut set, 5 second-order minimal cut set and 7 third-order minimal cut set.

Analisis Penurunan Capaian Target Produksi Bijih Nikel Menggunakan Metode Fault Tree Analysis di PT Ifishdeco Provinsi Sulawesi Tenggara

2020 ◽  
Vol 24 (1) ◽  
pp. 45-50
Author(s):  
Aryanti Virtanti Anas ◽  
Yoshita P Parissing ◽  
Irzal Nur ◽  
Sufriadin Sufriadin ◽  
Purwanto Purwanto ◽  
...  
Keyword(s):  
Fault Tree ◽  
Fault Tree Analysis ◽  
Top Down ◽  
Tree Analysis ◽  
Minimal Cut Set ◽  
Minimal Cut ◽  
Selective Mining ◽  
Cut Set ◽  
Production Target ◽  
Main Factor

Abstrak Proses produksi berarti menghasilkan suatu produk yang bernilai guna. Dalam suatu perusahaan pertambangan, produksi merupakan hal yang sangat penting, sehingga diperlukan perencanaan yang matang. Perusahaan menargetkan jumlah bahan galian yang akan diproduksi baik dalam jangka panjang, menengah maupun jangka pendek. Operasi produksi PT. Ifishdeco menggunakan bantuan alat gali muat excavator Komatsu PC 300 dimana terjadi penurunan produksi bijih nikel sebesar 19,94%. Target produksi sebesar 149.934 mt, namun capaian produksi hanya sebesar 116.603mt. Oleh karena itu, penelitian ini dilakukan untuk mengetahui faktor utama dan nilai probabilitas penyebab turunnya capaian produksi. Salah satu metode yang dapat digunakan untuk menganalisis faktor utama penyebab penurunan capaian produksi adalah menggunakan Fault Tree Analysis (FTA). Persamaan logika top down dari Fault Tree Analysis disubstitusi ke dalam aljabar Boolean hingga diperoleh minimal cut set. Minimal cut set merupakan persamaan akhir yang merincikan top down. Top event penurunan capai target produksi memiliki empat top down, yaitu faktor pengisian, kesiapan fisik alat, efektivitas kerja, dan waktu edar alat gali muat. Berdasarkan nilai probabilitas basic event tertinggi yang bernilai 1, maka faktor utama penyebab penurunan capaian produksi adalah dari faktor umur pakai alat tua, penjadwalan perawatan tidak teratur, kualitas alat buruk, dan proses selective mining.   Abstract Analysis of Decrease in Nickel Ore Production Targets Using the Fault Tree Analysis Method in PT Ifishdeco, Southeast Sulawesi Province. Production process meant produce product with beneficial value. At the mining company, production was very important, so it needed to be well-planned. Company was making target amount of digging material to be produced in long term, middle term, and short term. Production operation at PT Ifishdeco utilized digger loader equipment namely excavator Komatsu PC 300. There was decreasing in nickel ore production of 19,94%. Production target was 149,934 mt, but the company was only able to meet 116,603 mt. Objective of this study was to know main factor and probability value which caused the low production performance. One of methods to be used to analyze the main factor was Fault Tree Analysis (FTA). Top down logical equations of Fault Tree Analysis was substituted into Boolean algebra to get minimal cut set. Minimal cut set was a formula of the top down and used to calculate probability. Top event of the decreasing of the production target had four top downs which were filling factor, mechanical availability, effectivity of use, and cycle time of digger loader. Based on the highest probability of basic event which value was equal to 1, the main factor caused the decreasing of productivity were lifetime of equipment, unscheduled of maintenance, low quality of equipment, and selective mining.   Kata Kunci: Excavator, Work Effectivity, Boolean, Cut Set, Probability

scholarly journals Preliminary Hazard Analysis dan Fault Tree Analysis untuk Identifikasi Penyebab Kegagalan Sistem Pelumas Mesin Induk Kapal Penangkap Ikan

Jurnal Airaha ◽  
2018 ◽  
Vol 7 (02) ◽  
Author(s):  
Muhammad Zaki Latif A ◽  
Yuniar E. Priharanto ◽  
Djoko Prasetyo ◽  
Muhfizar Muhfizar
Keyword(s):  
Hazard Analysis ◽  
Fault Tree ◽  
Fault Tree Analysis ◽  
Tree Analysis ◽  
Minimal Cut Set ◽  
Minimal Cut ◽  
Cut Set

Kapal penangkap ikan di Indonesia sebagian besar menggunakan mesin diesel sebagai tenaga penggeraknya. Mesin diesel merupakan mesin mekanis dimana singgungan komponen tidak dapat dihindari, sehingga sistem pelumas mutlak diperlukan untuk mengurangi tingkat kerusakan komponen yang bersinggungan. Penurunan kemampuan sisteem pelumas berdampak pada kerusakan mesin. Tujuan penelitian ini untuk mengidentifikasi penyebab kerusakan sistem pelumas mesin diesel kapal penangkap ikan sehingga memudahkan untuk membuat keputusan dalam melakukan tindakan perawatan dan perbaikan sistem pelumas. Metode untuk mengidentifikasi tiap kegagalan yang mungkin terjadi menggunakan Preliminary Hazard Analysis (PHA) dan Fault Tree Analysis (FTA). PHA merupakan perangkat untuk mengidentifikasi potensi bahaya yang mengakibatkan kegagalan sistem, FTA merupakan perangkat untuk mengidentifikasi penyebab kegagalan sistem. FTA bekerja dengan menentukan kegagalan yang disebut sebagai “top event”, selanjutnya top event diidentifikasi hubungan faktor penyebab berbagai peristiwa kegagalan dengan pohon kesalahan yang menggunakan gerbang logika sederhana “and” dan “or”. Terbentuknya FTA dapat menentukan faktor penyebab kegagalan dengan minimal cut set. Berdasarkan hasil analisis, terdapat tiga penyebab utama mesin diesel mengalami kegagalan karena sistem pelumas adalah gagalnya komponen sistem pelumas yaitu  Kebocoran internal, (Screen pelumas + alarm tekanan + manometer + petugas), dan (Pompa pelumas + alarm tekanan +  manometer + petugas).

FTAe – Fault Tree Analysis in Microsoft Excel

2014 ◽  
Vol 889-890 ◽  
pp. 591-594
Author(s):  
Richard Kuracina ◽  
Denis Šandor ◽  
Karol Balog
Keyword(s):  
Fault Tree ◽  
Fault Tree Analysis ◽  
Software Tool ◽  
Short Description ◽  
Microsoft Excel ◽  
Tree Analysis ◽  
Minimal Cut Sets ◽  
Minimal Cut ◽  
Cut Set

FTAe is software tool for Fault Tree Analysis in Microsoft Excel. This paper is focused on short description of created FTAe. A brief description of Fault Tree Analysis is in the first part of paper. The Structure, Logic and Minimal Cut Sets in Fault Tree analysis is described too. Next part of this paper is focused on the choice of algorithm for cut set calculation and brief description of structure of FTAe. Finally, advantages of FTAe software in Microsoft Excel are described in conclusions.

scholarly journals Qualitative Analysis of Commercial Services in MEC as Phased-Mission Systems

2020 ◽  
Vol 2020 ◽  
pp. 1-11 ◽  
Author(s):  
Yuhuan Gong ◽  
Yuchang Mo
Keyword(s):  
Single Phase ◽  
Fault Tree ◽  
Fault Tree Analysis ◽  
Tree Analysis ◽  
The Past ◽  
Minimal Cut Set ◽  
Wide Range ◽  
Cut Set ◽  
Phase Systems ◽  
New Algorithms

Currently, mobile edge computing (MEC) is one of the most popular techniques used to respond to real-time services from a wide range of mobile terminals. Compared with single-phase systems, commercial services in MEC can be modeled as phased-mission systems (PMS) and are much more complex, because of the dependencies across the phases. Over the past decade, researchers have proposed a set of new algorithms based on BDD for fault tree analysis of a wide range of PMS with various mission requirements and failure behaviors. The analysis to be performed on a fault tree can be either qualitative or quantitative. For the quantitative fault tree analysis of PMS by means of BDD, much work has been conducted. However, for the qualitative fault tree analysis of PMS by means of BDD, no much related work can be found. In this paper, we have presented some efficient methods to calculate the MCS encoding by a PMS BDD. Firstly, three kinds of redundancy relations-inclusive relation, internal-implication relation, and external-implication relation-within the cut set are identified, which prevent the cut set from being minimal cut set. Then, three BDD operations, IncRed, InImpRed, and ExImpRed, are developed, respectively, for the elimination of these redundancy relations. Using some proper combinations of these operations, MCS can be calculated correctly. As an illustration, some experimental results on a benchmark MEC system are given.

Analysis on Dynamic Fault Tree Based on Fuzzy Set

2011 ◽  
Vol 110-116 ◽  
pp. 2416-2420 ◽  
Author(s):  
Li Ping Yang
Keyword(s):  
Fuzzy Set ◽  
Fault Tree ◽  
Dynamic Logic ◽  
Fault Tree Analysis ◽  
Logic Gates ◽  
Minimum Cut ◽  
Tree Analysis ◽  
Dynamic Fault Tree ◽  
Large Complex System ◽  
Cut Set

In case of fault tree analysis of large complex system, the probability of bottom event in dynamic fault tree is uncertain in some cases. To address the problem, the paper presented a dynamic fault tree analysis method based on fuzzy set computation. The method separates logic attributes and timing attributes of dynamic logic gates. It can convert dynamic fault tree into static fault tree not considering timing constraints and obtain minimum cut set of static fuzzy fault tree with set operations, then the concept of minimum cut set is extended to dynamical minimum cut sequence. Thus, the dynamic fault tree was analyzed in both qualitative and quantitative aspects, which solve the problem that it is difficult to assign value of event probability in previously process.

Reliability analysis of helicopter emergency flotation system

2020 ◽  
Vol 64 (1-4) ◽  
pp. 1001-1009
Author(s):  
Xing Guo ◽  
Jian-Hong Sun ◽  
Ke Liu ◽  
Tong Zhang ◽  
Ming-Qi Li ◽  
...  
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Method ◽  
Reliability Analysis ◽  
Fault Tree ◽  
Fault Tree Analysis ◽  
Reliability Design ◽  
Minimal Cut Set ◽  
The Monte Carlo Method ◽  
Cut Set ◽  
Event Based

The reliability of the emergency flotation system of helicopters is analysed by using fault tree analysis and the Monte Carlo method. We constructed a fault tree with the failure of system as the top event and obtained the minimal cut set, the ranking of the structural importance of the bottom events and the probability of the occurrence of the top event. Based on the system fault tree, a Monte Carlo simulation model of the emergency flotation system is established by using Matlab/Simulink. The results show that the Monte Carlo method is feasible and effective for the reliability analysis of the emergency flotation systems of helicopters. Furthermore, the comparison between the criticality importance and mode importance of each subsystem suggests that the control component is the weakest part of the emergency flotation systems, thereby providing a basis for system reliability design and fault diagnosis.

scholarly journals Identifikasi Faktor-Faktor Penyebab Berkontribusi Terjadinya Kegagalan Konstruksi Jalan dengan Metode Fault Tree Analysis (FTA)

2021 ◽  
pp. 53-63
Author(s):  
Utami Dewi Arman Arman ◽  
Jihan Melasari ◽  
Septia Edrian Saputri
Keyword(s):  
Fault Tree ◽  
Fault Tree Analysis ◽  
Tree Analysis ◽  
Cut Set

Kegagalan konstruksi merupakan suatu kondisi penyimpangan, kesalahan dan kerusakan dari hasil pekerjaan konstruksi yang dapat mengakibatkan keruntuhan bangunan atau konstruksi. Penelitian ini bertujuan untuk mengidentifikasi faktor-faktor yang berkontribusi terjadinya kegagalan struktur jalan Bukit Manggis Kabupaten Solok Selatan menurut persepsi para stakeholder proyek. Metode penelitian menggunakan metode deskriptif kualitatif melalui observasi di lokasi proyek dan wawancara mendalam kepada para stakeholder. Hasil data wawancara dianalisis menggunakan metode Fault Tree Analysis (FTA) dan Methode for Obtaining Cut Set (MOCUS). Berdasarkan hasil identifikasi, di peroleh 7 (tujuh) faktor-faktor yang berkontribusi terjadinya kegagalan pada struktur jalan yaitu; (1) Perencanaan, (2) Pelaksanaan, (3) Bencana alam, (4) Komunikasi, (5) Budaya organisasi, (6) Biaya serta (7) Kondisi iklim.  Faktor-faktor kegagalan konstruksi paling dominan menurut persepsi stakeholder adalah bencana alam, kondisi iklim, budaya organisasi dan komunikasi. Maka dari itu, diharapkan masing-masing stakeholder memberikan perhatian khusus terhadap faktor penyebab yang telah diidentifikasi.

Sign in / Sign up

Export Citation Format

Share Document