Reliability Engineering Techniques Applied to the Human Failure Analysis Process

Human reliability and human error are factors that are present in all areas: industrial, economic, social, etc. All these areas require to a greater or lesser extent a physical and mental effort to satisfy their own needs, those of others, or established requirements that, depending on the circumstances and the nature of the person, can lead to errors. Certainly, it is not possible to find a single human reliability method that can meet all the expectations and technical demands related to the analysis of human errors. However, it is important to note that the orientation of all human reliability methods is focused on the study and analysis of the risk factor (frequency by consequences). In other words, as can be observed throughout this chapter, all human reliability methodologies seek to help us reduce the uncertainty in the process of evaluating the frequencies of unforeseen events (human errors) and the consequences that such human errors can bring to safety, the environment, and the operations within the framework of an industrial production process.

Effectiveness of Quality of Service towards Commitment of Suppliers with Reference to SME’s in Automobile Industry

Service quality is a focused evaluation that reflects the vendor's perception of specific dimensions of service. Though there is a problem with the automobile industry Covid-19 pandemic the sector may grow further in near future. The main objective is to examine the essential dimensions of service quality i.e. RATER- Reliability, assurance, tangibles, empathy and responsiveness of SME’s in the automobile industry and its effect on vendor’s satisfaction and to find out the perception of suppliers towards supply chain with the companies. For this, a sample of 50 was collected from the respondents were percentage analysis, Descriptive statistics, Multiple regression, Kruskal Wallis test, and one-way ANOVA were used as tools to analyse the data. The conclusion is that dimensional factors level of acceptance towards sourcing products from a limited number of suppliers, level of acceptance towards establishing clear criteria, and level of acceptance towards Suppliers collaborating with suppliers in materials are taken for decision making process of the study. It also reveals that while taking a decision on these dimensions the factor frequency of making supply should be taken for decision making process of the study.

Evaluating the utility of routine screening catheterisation before interstage discharge of infants with single-ventricle physiology

Introduction:Interstage mortality causes are often unknown in infants with shunt-dependent univentricular defects. For 2 years, screening catheterisation was encouraged before neonatal discharge to determine if routine evaluation improved interstage outcomes.Methods:Retrospective single-centre review of home monitoring programme from December, 2010 to June, 2012. Composite scores were created for physical examination/echocardiography risk factors; catheterisation risk factors; and interstage adverse events. Composite scores were compared between usual care and screening catheterisation groups. The ability of each risk factor composite to predict interstage adverse events, individually and in combination, was assessed with sensitivity, specificity, and receiver operating characteristic curves.Results:There were 27 usual care and 32 screening catheterisation patients. There were no significant differences between groups except rates of catheterisation before discharge (29.6 versus 100%, p < 0.001). Usual care patients who underwent catheterisation for clinical indications had higher intervention rates (37.5 versus 3.1%, p = 0.004). Physical examination/echocardiography risk factor frequency was similar, but usual care patients with catheterisation had a higher catheterisation risk factor frequency. Interstage adverse event frequency was similar (48.2 versus 53.1%, p = 0.7). For interstage adverse event prediction, sensitivity for the physical examination/echocardiography, catheterisation, and either risk factor composites was 53.3, 72, and 80%, respectively; specificity was 59, 60, and 48%. The area under the receiver operating characteristic curve was 0.56, 0.66, and 0.64.Conclusion:Screening catheterisation evaluation offered slightly increased sensitivity and specificity, but no difference in interstage adverse event frequency. Given this small advantage versus known risks, screening catheterisations are no longer encouraged.

PERFORMANCE ANALYSIS FOR DIRECTION-FINDING CIRCULAR ANTENNA ARRAY

This paper considers circular antenna arrays comprised of symmetrical dipole radiators applied in communication, navigation and monitoring systems. Despite their widespread use, a number of significant issues is underinvestigated. Among them are frequency dependence of the antenna factor (the ratio of the electric field intensity module to the voltage amplitude at the load connected to the output terminals) of the circular antenna array elements in the correct electrodynamic setting. The purpose of this paper is to analyse the antenna factor frequency dependence of a single dipole antenna with different geometry and load both in free space and as circular antenna element. The estimation of phase difference error between the circular antenna array elements caused by their cross coupling is also of interest.Specific expressions are obtained for the antenna factor of the dipole antenna for single-mode and three-mode approximations. The limits of their applicability in frequency band are considered. The solution to the coupled integral equations is obtained using the Galerkin method with piecewise sinusoidal current distribution and with an arbitrary number of basis functions for eight- and four-element circular antenna array. This solution may be generalized to an arbitrary number of circular antenna array elements. It is demonstrated that to improve the antenna factor frequency dependence it is advisable to use dipole antennas with high-resistance load, as well as with large diameter. Phase errors for different circular antenna array element signals are considered with respect to the reference element. The dependence of these phase errors on the circular antenna array geometry is presented. It is concluded that there are significant oscillations of the antenna factor when the dipole is the part of the circular antenna array. They are caused by cross coupling between the circular antenna array elements, which significantly depend on the element spacing. The results presented may be of interest to phase direction finder development engineers.

DISTRIBUSI UKURAN IKAN TERI (Stolephorus sp) YANG DITANGKAP PADA PERIKANAN BAGAN TANCAP DI MUARA SUNGSANG SUMATERA SELATAN (Size Distribution of Anchovy (Stolephorus sp.) Caught in Stationary Liftnets at Sungsang Estuary South Sumatera)

<p><strong>ABSTRACT<br /> </strong><br />The anchovy (Stolephorus sp.) in Muara Sungsang estuary South Sumatera are generally caught by stationary liftnet. Morphometric studies are essential to determine the growth form and growth rate of species, which is very much important for proper utilization and management of the population of the species. This study aimed to determine the size structure and growth pattern of the anchovy caught by stationary liftnet. The size structure, length -weight relationship and the condition factor of anchovy were computed. The anchovy samples were taken in July 2013 (750 samples) and September 2013 (1950 samples). Results showed that the population of anchovy was dominated by length frequency distribution of 65 mm during study on July 2013 and 75 mm during study on September 2013. Both populations were dominated by weight frequency distribution 2 gram. The anchovy that caught on September 2013 were more allowable catch than on July 2013. The growth pattern of anchovy was negative allometric. The relative condition factor (Kn) value in September 2013 was higher than in July 2013. It indicated that the environmental conditions at Muara Sungsang estuary are suitable for growth of anchovy’s and still safe from fishing pressure.</p><p>Keywords: allometric, anchovy, condition factor, frequency distribution</p><p> <strong><br />ABSTRAK</strong></p><p>Ikan Teri (Stolephorus sp.) di Muara Sungsang Sumatera Selatan umumnya ditangkap menggunakan bagan tancap. Studi morfometrik berguna untuk menentukan bentuk pertumbuhan dan laju pertumbuhan spesies. Hal ini berguna untuk manajemen populasi dan sebagai informasi tentang stok atau kondisi organisme. Disamping itu, sebagai dasar dalam upaya pengelolaan dan pemanfaatan ikan teri di masa akan datang. Penelitian ini bertujuan untuk mengetahui struktur ukuran dan pola pertumbuhan ikan teri hasil tangkapan bagan tancap. Data ikan teri didapatkan pada bulan Juli 2013 (750 sampel) dan September 2013 (1950 sampel). Hasil penelitian menunjukkan bahwa populasi ikan teri didominasi oleh distribusi frekuensi panjang 65 mm pada bulan Juli 2013 dan 75 mm pada bulan September 2013. Distribusi frekuensi berat teri pada kedua bulan tersebut sama yaitu 2 gram. Penangkapan ikan teri pada bulan September 2013 lebih layak tangkap dibandingkan pada bulan Juli 2013. Pertumbuhan ikan teri bersifat negative allometric. Nilai Faktor kondisi (Kn) pada bulan September 2013 lebih tinggi daripada bulan Juli 2013. Hal ini mengindikasikan bahwa kondisi lingkungan Muara Sungsang cocok untuk pertumbuhan ikan teri dan masih aman dari tekanan aktivitas penangkapan.</p><p>Kata kunci: allometrik, teri, faktor kondisi,distribusi frekuensi</p>