Optimizing a damped system – a case study

We consider a second-order damped-vibrational system described by the equation M ?+C(v) [xdot]+K x=0, where M, C(v), K are real, symmetric matrices of order n. We assume that the undamped eigenfrequencies (eigenvalues of (λ² M+K) x=0) ω₁, ω₂, …, ω _n , are multiple in the sense that ω₁=ω₂, ω₃=ω₄, …, ω _n?1=ω _n , or are given in close pairs ω₁ ≈ ω₂, ω₃ ≈ ω₄, …, ω _n?1 ≈ ω _n . We present a formula which gives the solution of the corresponding phase space Lyapunov equation, which then allows us to calculate the first and second derivatives of the trace of the solution, with no extra cost. It can serve for the efficient trace minimization.     

Reverse engineering in the design of turbine blades – a case study in applying the MAMDP

This paper presents a case study on the reverse engineering of turbine blades used in nuclear power generators. Reverse engineering has been widely recognised as a crucial step in the product design cycle. However, major problems with current reverse engineering technology are the inefficient surface reconstruction process, lack of digitising accuracy control in the data digitisation process, and bottlenecks resulted from huge amounts of digitised surface points in the surface modeling process. Moreover, under this limitation, modern concurrent engineering concepts are difficult to implement to obtain optimal product design. This study applies a developed reverse engineering approach – the modified adaptive model-based digitizing process (MAMDP) to the 3D geometric design of turbine blades. The approach integrates surface digitising and modeling processes of turbine blades into a single surface reconstruction process. Using the approach, accurate product CAD models can be efficiently generated and the product design cycle of turbine blades can be successfully linked.     

Optimisation of maintenance concept choice using risk-decision factor – a case study

This article is concerned with the state estimation problem for a kind of non-uniform sampling dynamic system. The system is described at a certain sampling rate in discrete form. A sensor observes the target successively, while the samples are obtained non-uniformly and the sampling points in each sampling periods may be different. To generate the optimal state estimate, state prediction and innovation are carried out step-by-step similar to Kalman filter (KF), but before innovation in each sampling period, measurements should be properly disposed and augmented. It is shown that our main results improve and extend the existing KF for which the samples are obtained multirate non-uniformly. Measurements randomly missing with Bernoulli distribution are also considered in this article. Finally, the feasibility and efficiency of the presented algorithm is illustrated by a numerical simulation example.     

Conceptualizing task-technology fit and the effect on adoption – A case study of a digital textbook service

Although information technology has revolutionized virtually every aspect of how we interact with products and services, it has changed learning to a surprisingly small degree. In a study of a digital textbook service, we provide a new conceptual definition and measurement of technology fit. We conceptualize task-technology fit as how well a technology is integrated with a set of interrelated tasks included in achieving the goal of the behavior where the technology is used. Whereas research on technology adoption typically explains around 40 percent of the variance in motivation to adopt, our model explains as much as 76 percent.     

Exploring the social competence of students with autism spectrum conditions in a collaborative virtual learning environment – The pilot study

Social reciprocity deficits are a core feature of the autism spectrum conditions (ASCs). Many individual with ASCs have difficulty with social interaction due to a frequent lack of social competence. This study focuses on using a virtual learning environment to help the deficiencies of social competence for people with ASCs, and to increase their social interaction. Specifically, it primitively explores social competence in collaborative virtual learning environment (CVLE) systems, and behavioral performance in social and cognitive interactions. Thus, this CVLE-social interaction system involves a 3D expressive avatar, an animated social situation, and verbal as well as text-communication. A preliminary empirical study involved CVLE-social interaction systems. Three participants who had been diagnosed with ASCs were conducted using a multiple baseline research for evidence of improved social competence through usage of the system. The experimental study consisted of 17 days; and the results showed that using the CVLE-social interaction system had significant positive effects on participants’ performance, both within the CVLE-social interaction system and in terms of reciprocal social interaction learning.     

Safety management of waterway congestions under dynamic risk conditions—A case study of the Yangtze River

With the continuous increase of traffic volume in recent years, inland waterway transportation suffers more and more from congestion problems, which form a major impediment to its development. Thus, it is of great significance for the stakeholders and decision makers to address these congestion issues properly. Fuzzy Techniques for Order Preference by Similarity to an Ideal Solution (TOPSIS) is widely used for solving Multiple Criteria Decision Making (MCDM) problems with ambiguity. When taking into account fuzzy TOPSIS, decisions are made in a static scenario with fixed weights assigned to the criteria. However, risk conditions usually vary in real-life cases, which will inevitably affect the preference ranking of the alternatives. To make flexible decisions according to the dynamics of congestion risks and to achieve a rational risk analysis for prioritising congestion risk control options (RCOs), the cost-benefit ratio (CBR) is used in this paper to reflect the change of risk conditions. The hybrid of CBR and fuzzy TOPSIS is illustrated by investigating the congestion risks of the Yangtze River. The ranking of RCOs varies depending on the scenarios with different congestion risk conditions. The research findings indicate that some RCOs (e.g. “Channel dredging and maintenance”, and “Prohibition of navigation”) are more cost effective in the situation of a high level of congestion risk, while the other RCOs (e.g. “Loading restriction”, and “Crew management and training”) are more beneficial in a relatively low congestion risk condition. The proposed methods and the evaluation results provide useful insights for effective safety management of the inland waterway congestions under dynamic risk conditions.     

Monitoring intense dust storms over the Indian region using satellite data – a case study

Dust storms are normally considered to be natural hazards. During such events, dust aerosol is loaded into the atmosphere, directly reducing visibility and effectively reflecting solar radiation back to space. In the present study, an intense dust storm was monitored during the first week of June 2010 using Moderate Resolution Imaging Spectroradiometer (MODIS) Terra and Aqua data over the Indian region. A dust cloud was detected using a combination of MODIS reflective and emissive channels and moving trace/spread monitored by its multi-temporal data. The MODIS Terra-derived aerosol optical depth at 550 nm (AOD₅₅₀) and the aerosol index (AI) obtained from the Ozone Monitoring Instrument (OMI) were used in conjunction with National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) reanalysis wind fields for the monitoring of dust clouds. The study reveals that the movement of a high concentration of dust clouds coincided with the NCEP/NCAR reanalysis meridional and zonal wind fields (>8 m s^?1) at pressure levels of 700 hPa. The Cloud–Aerosol Lidar Pathfinder Satellite Observations (CALIPSOs) that derive vertical feature mask images also suggested that the vertical extent of the dust aerosol layer was at a height of about 6 km over northern India on 2 June 2010. The roles of long-range transport of dust over the entire Gangetic plane are analysed using back trajectories from the National Oceanic and Atmospheric Administration (NOAA) Hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model. Back trajectory analysis suggests that dust clouds moving over long distances entered from the western side of India on 1 June 2010.     

Effective digital collaboration in the construction industry – A case study of BIM deployment in a hospital construction project

Building information modeling (BIM) and related digital innovations can serve as a catalyst for more transparency, tighter integration, and increased productivity in the architecture, engineering, and construction industry. Yet, many project teams struggle with how to work based on the new technology. Collaborative design based on shared information systems like BIM requires changing traditional and institutionalized work practices and routines. A case study of integrated BIM design in a large healthcare construction project serves as an example for how commonly experienced challenges can be overcome. The project has been awarded BuildingSMART's 2015 award for ‘outstanding open BIM practice’ making it Norway's role model for BIM practice. Based on diffusion of innovations theory, we identified the following set of key factors enabling digital collaboration in this project: change agents, new roles and responsibilities, a cloud computing infrastructure, BIM contracts, and a BIM learning environment. The findings presented in this article may serve as an example for BIM implementation and collaborative work in construction projects.     

Simulation of multibody systems with the use of coupling techniques: a case study

Simulation coupling (or cosimulation) techniques provide a framework for the analysis of decomposed dynamical systems with the use of independent numerical procedures for decomposed subsystems. These methods are often seen as very promising because they enable the utilization of the existing software for subsystem analysis and usually are easy to parallelize, and run in a distributed environment. For example, in the domain of multibody systems dynamics, a general setup for “Gluing Algorithms” was proposed by Wang et al. It was intended to provide a basis for multilevel distributed simulation environments. The authors presented an example where Newton’s method was used to synchronize the responses of subsystem simulators.     

Ensemble based technique for the assessment of fetal health using cardiotocograph – a case study with standard feature reduction techniques

Multimedia Tools and Applications - Intrauterine fetal hypoxia is one of the leading cause of perinatal mortality and morbidity. This can eventually lead to severe neurological damage like cerebral...     

SOA in practice – a study of governance aspects

The academic literature on Service Oriented Architecture (SOA) governance is based on theories and assumptions rather than practices, whereas the SOA governance frameworks proposed by Information Technology (IT) vendors are made to suit their products. Research shows that the problems with SOA governance in practice are among the major reasons of SOA failures. An extensive literature review that covers SOA, IT governance and SOA governance has been carried out part of this research. The purpose of this research paper is to increase our understanding of SOA governance and to show which SOA aspects organizations should consider when adopting a SOA governance framework. Based on a literature review, this study first proposes a list of SOA aspects to be considered when implementing SOA governance. By adopting an interpretive research methodology – based on interviews with professionals and practitioners in the fields of IT governance and SOA governance – this research paper examines the importance of these aspects. The results provide a theoretical conceptualization of SOA aspects that can be used to assess SOA governance practices and provide guidance to improve them.     

Acceptance of software process innovations – the case of extreme programming

Extreme programming (XP), arguably the most popular agile development methodology, is increasingly finding favor among software developers. Its adoption and acceptance require significant changes in work habits inculcated by traditional approaches that emphasize planning, prediction, and control. Given the growing interest in XP, it is surprising that there is a paucity of research articles that examine the factors that facilitate or hinder its adoption and eventual acceptance. This study aims to fill this void. Using a case study approach, we provide insights into individual, team, technological, task, and environmental factors that expedite or impede the organization-wide acceptance of XP. In particular, we study widely differing patterns of adherence to XP practices within an organization, and tease out the various issues and challenges posed by the adoption of XP. Based on our findings, we evolve factors and discuss their implications on the acceptance of XP practices.     

Predicting students’ learning style using learning analytics: a case study of business management students from India

ABSTRACT

Business Management Education in India has shown an upward growth trend in the last couple of decades. Due to the diverse nature of the course, students from diverse academic backgrounds are being admitted to the course. Therefore, differences in students’ abilities and their learning styles have a significant effect on their learning outcomes. Meanwhile, with the development of learning technologies, learners can be provided a more effective learning environment to optimise their learning. The purpose of this study was to develop a model to automatically detect the students’ learning styles from their personal, academic and social media data and make recommendations for students, teachers, educators and administrators for overall improvement of learning outcomes. Data analysis in this research was represented using data collected from post-graduate business management students in India. A 10-fold cross-validation was used to create and test the models. The data were analysed by R and R-Studio. Classification accuracy, Precision, Recall, Kappa, ROC curve and F measure were observed. The results showed that the accuracy of classification by the C4.5 technique had the highest value at 95.7%, and it could be applied to develop Felder–Silverman’s learning style while taking into consideration students’ academic, personal information and social media preferences.     

A fuzzy PLC with gain-scheduling control resolution for a thermal process – a case study

This paper presents a case study on the practical implementation of a fuzzy-PLC system for a thermal process. The theoretical study indicates that the inferior performance of fuzzy-controlled processes around a reference point is often caused by insufficient resolution of the fuzzy inference. The limitations of ladder logic cannot support complex algorithms for resolution improvement. A simple gain adaptation method is presented here, to achieve smooth fuzzy control, that can be easily implemented in a PLC system. Real-time experiments on an unidentified thermal process show the effectiveness of the approach, as well as the robustness of the fuzzy controller with respect to the time-varying features of the process.     

Centralisation – the route to controlling payment costs

The wave of bank mergers and acquisitions that swept the financial services industry during the late 1990s have as yet unrealised promises of better value for money. With the financial sector's economic downturn biting into profits and bringing costs under the microscope more than ever before, banks need to reassess their card payments processing strategies in order to eliminate as much unnecessary expenditure as possible.     

Blind-friendly user interfaces – a pilot study on improving the accessibility of touchscreen interfaces

Multimedia Tools and Applications - Touchscreen devices such as a smartphone, smartwatch, and tablets are essential assistive devices for visually impaired and blind people in performing activities...     

Behavioural data in the design of ergonomic computer terminals and workstations—a case study

Abstract

Manufacturers of office automation equipment, in their design of ergonomic computer terminals and office furniture, are encountering needed design data which is sometimes weak, absent, erroneous or inapplicable to the office-worker situation under consideration. In some instances, office automation manufacturers simply follow standards. In others, manufacturers make assumptions as to the best design, and in others, design decisions were based on testing results and conclusions.This paper reviews the ergonomic tools and features incorporated into the design of one office automation manufacturer's terminals and workstations. The short fall of applicable design data relevant to comfort versus extremes of motion in biomechanics, to keyboard home row height and slope angle to viewing distance, as well as to reverse video and surface colour are presented, along with the design resolution of these parameters. Further, certain aspects of posture recently published are discussed.     

The implications of serial correlation and time-lag effects for the impact study of climate change on vegetation dynamics – a case study with Hulunber meadow steppe,Inner Mongolia

Ecological time series data are widely used in ecological research thanks to the development of remote-sensing technologies and fixed ecological research stations. However, the serial correlation issue with time series, which violates the fundamental assumption of independence for traditional statistical models or analysis, is rarely considered by ecologists in vegetation–climate relationship research. In addition, the issue of time lags between climate change and vegetation response is also often ignored. Inadequate consideration of these issues produces misleading results in some cases. In this article, we propose an approach based on the Autoregressive Integrated Moving Average (ARIMA) model and the nonparametric test to address serial correlation issue and distribution requirements for the valid statistical analysis of time series data. With Hulunber meadow steppe as a case, we applied this approach to analyse the role of climate factors in vegetation dynamics based on leaf area index (LAI) data and climatic data. The results showed that the LAI dynamics of Hulunber meadow steppe were mainly related to temperature with the time lag of zero, whereas the impact of precipitation on LAI dynamics was not statistically obvious. The comparison of regression models that deal with serial correlation and residual normality to different extents showed that ignoring the serial correlation issue with time series data likely produces misleading results, highlighting the importance of serial correlation removal. The combination of nonparametric correlation tests with ARIMA-based cross-correlation analysis also proved quite useful in reducing the chance of spurious correlation and time lags resulting from outlier values in ARIMA-based cross-correlation.