Exploring technical and non-technical competencies of navigators for autonomous shipping

The emergence of autonomous ship technologies has attracted a growing body of academic studies, regulatory discussions and exploration endeavours in recent years. With the introduction of new technology comes the need for the seafarers to be trained in its use. The purpose of this paper is 1) to examine the suitability of the International Convention on Standards of Training, Certification and Watchkeeping for Seafarers (STCW) Table A-II/1 competence framework for navigators under Maritime Autonomous Surface Ship (MASS) operations, and 2) to propose future technical and non-technical competencies that will be needed in autonomous shipping era. A mixed method approach was adopted with collection of both quantitative and qualitative data through a survey instrument developed on the basis of the literature and current STCW Table A-II/1, in which the 66 Knowledge, Understanding & Proficiency (KUP) requirements for navigators were converted into measurement items. Statistical analysis of the data has aided in identifying a list of key technical and non-technical competence requirements for the navigators under MASS operations. The results can be used as an input for revision of the STCW competence requirements and to facilitate the preparation and implementation of novel training frameworks for autonomous shipping

Damage detection of truss structure based on the variation in axial stress and strain energy predicted from incomplete measurements

This study derives the static equilibrium equation of a damaged system on the basis of stiffness change due to damage as well as the constraint forces at measurements required for obtaining the measured data. Based on the derived equations, this work provides an analytical method to detect damage from the stress and strain energy variations between intact and damaged truss structures. The applicability of the proposed method is evaluated in detecting multiple damages of low rate in the truss structure from measured data contaminated by external noise. It is demonstrated that it is possible to properly detect damage in an isolated substructure by partitioning the damage-expected substructure from an entire structure and using the displacements measured at the boundary of the partitioned subsystem. The partitioning method has the benefits in reducing the computational time and measured data as well as improving the effectiveness of the damage detection process

Ansiedad y desmotivación en el aprendizaje del inglés en estudiantes de tercer año de secundaria de Corea del Sur

Because of the high level of anxiety and academic pressure associated with the college entrance exam in South Korea, this study investigated the effects of English learning anxiety on English learning demotivation and academic achievement in third-year high school students. To determine the correlations of the effect of English learning anxiety on both components, 249 participants were selected from nine third-year student classes at an academic high school in Gyeonggi Province, South Korea, to complete questionnaires, the data from which were analysed using quantitative statistical methods. The regression analyses revealed that the English learning anxiety in the male and female students with top grades had positively and significantly affected their academic achievement. However, except for high-level male learners, demotivation was not found to have any effect on student achievement. The results suggested that it is important to design education-friendly measures to enhance third-year high school student motivation and alleviate any excessive anxiety.Debido al alto nivel de ansiedad y presión académica asociados con el examen de ingreso a la universidad en Corea del Sur, este estudio investigó los efectos de la ansiedad por aprender inglés en la desmotivación del aprendizaje del inglés y el rendimiento académico en estudiantes de tercer año de secundaria. Para determinar las correlaciones del efecto de la ansiedad por aprender inglés en ambos componentes, se seleccionaron 249 participantes de nueve clases de estudiantes de tercer año en una escuela secundaria académica en la provincia de Gyeonggi, Corea del Sur, para completar cuestionarios, cuyos datos se analizaron utilizando métodos cuantitativos métodos de estadística. Los análisis de regresión revelaron que la ansiedad por aprender inglés en los estudiantes masculinos y femeninos con las mejores calificaciones había afectado positiva y significativamente su rendimiento académico. Sin embargo, a excepción de los estudiantes varones de alto nivel, no se encontró que la desmotivación tuviera ningún efecto en el rendimiento de los estudiantes. Los resultados sugirieron que es importante diseñar medidas favorables a la educación para mejorar la motivación de los estudiantes de tercer año de secundaria y aliviar cualquier ansiedad excesiva

Leaders’ Influence Tactics for Safety: An Exploratory Study in the Maritime Context

A growing body of research has pointed out effective leadership as an important influencing factor for safety performance in various high-risk industrial contexts. However, limited systematic knowledge is available about how leaders can effectively persuade rule compliance, and stimulate actions and participation. Recognizing effective means of influence is of value for safety leadership development and evaluation. This study seeks to empirically investigate leaders’ influence tactics for safety in a maritime context. Qualitative exploration is performed with data being collected through focus group discussions and individual interviews with 41 experienced shipboard leaders from various shipping sectors. Five core influence tactics—coaching, role modeling, pressure, consultation and exchange tactics—appeared to be the shipboard leaders’ effective tactics to influence subordinates’ safety compliance and participation behaviors in ship operations. Safety leadership influences flow from exemplification, expert and personal sources of power, and being pursued through soft and rational influence tactics rather than coercion or constructive inducements. The results indicate that the more relationship-oriented the leaders are, the more effective their safety leadership would be in influencing safety behaviors. The implication of the results for maritime safety leadership research, maritime education and training are discussed

Conversion from a Bio-inert Glass to a Glass with Bio-active Layer by Heat-treatment in an Oxidation Atmosphere

AbstractThe surface of iron-bearing bio-inert glasses was modified by heat-treatment in an oxidizing atmosphere near the glass transition temperature. The modified surfaces after 7 days immersion in simulated body fluid (SBF) solution were analyzed by means of micro-Raman spectroscopy, SEM, and EDS. All investigated glasses except for the glass with NC = 2.6 were able to form hyroxycarbonate apatite (HCA) on their surfaces. The thickness of an HCA surface layer increased with decreased oxygen partial pressure. The cross-sectional micrographs were nearly similar to the 45S5 Bioglass®

The impact of pharmacodynamic parameters on prediction of clinical outcome in HIV-1 infected patients and HCV patients with HIV co-infection

The objective of this project was to use pharmacometric approaches to investigate the impact of in vivo pharmacodynamic (PD) parameters on clinical outcome in patients infected with human immunodeficiency (HIV) or hepatitis C (HCV) virus. Pharmacometrics is an emerging science based on developing and applying mathematical/statistical methods to characterize and predict pharmacokinetic (PK) and PD behavior, and to quantify uncertainty inherent in information about that behavior. The degree to which viral infection is inhibited at a given antiviral drug concentration depends on the IC50, the concentration inhibiting replication by 50%, and the slope of the relationship between drug effectiveness and concentration (γ). In vitro experiments demonstrated that each antiretroviral (ARV) class has a characteristic γ associated with inhibition of HIV replication. However, whether γ; is simply a shape factor that improves description of PK/PD data, or a fundamental parameter that can characterize in vivo efficacy, was not known. The first set of studies used integrated population PK-PD/HIV viral dynamic models to reveal that higher γ values are associated with better clinical outcome (larger log10 viral load decline; higher proportion of patients with undetectable viral load). However, the impact of γ became insignificant upon emergence of drug resistance. These studies also demonstrated that inclusion of γ improved PD models, although accurately estimating inter-individual variability in γ with a short-term monotherapy study design in HIV-infected patients was not possible. The second set of studies used integrated population PK-PD/HCV viral dynamic models to explore short-term clinical outcome associated with pegylated interferon (PEG-INF)-based treatment. These studies demonstrated no difference in γ between patients who attained sustained virologic response (SVR) and those who did not (NR). In contrast, estimates of IC50 and death rate for infected cells were significantly different between SVRs and NRs. Experiments also demonstrated that long-term HCV treatment outcome can be predicted using a population PK-PD/HCV viral dynamic model based on data obtained from a two-week PEG-INF-based treatment. Taken together, the results of this dissertation project indicate that pharmacometric approaches are useful in revealing the impact of in vivoPD parameters on clinical outcome in HIV and HCV infection.Doctor of Philosoph