Coupling dynamic simulation and interactive multiobjective optimization for complex problems: An APROS-NIMBUS case study

Dynamic process simulators for plant-wide process simulation and multiobjective optimization tools can be used by industries as a means to cut costs and enhance profitability. Specifically, dynamic process simulators are useful in the process plant design phase, as they provide several benefits such as savings in time and costs. On the other hand, multiobjective optimization tools are useful in obtaining the best possible process designs when multiple conflicting objectives are to be optimized simultaneously. Here we concentrate on interactive multiobjective optimization. When multiobjective optimization methods are used in process design, they need an access to dynamic process simulators, hence it is desirable for them to coexist on the same software platform. However, such a co-existence is not common. Hence, users need to couple multiobjective optimization software and simulators, which may not be trivial. In this paper, we consider APROS, a dynamic process simulator and couple it with IND-NIMBUS, an interactive multiobjective optimization software. Specifically, we: (a) study the coupling of interactive multiobjective optimization with a dynamic process simulator; (b) bring out the importance of utilizing interactive multiobjective optimization; (c) propose an augmented interactive multiobjective optimization algorithm; and (d) apply an APROS-NIMBUS coupling for solving a dynamic optimization problem in a two-stage separation process.     

Action research in policy making: a case in the dairy industry in Gujarat,India

Action research has been extensively used world-wide for decision making related to policy due to its nature of involving the researcher and decision maker in the process. Following independence in India, one of the major revolutions was brought about in the dairy sector with regard to complete management systems. Most innovations and changes occurred in the line function while the staff function was more often neglected in the overall change. The authors undertook an action research study focusing on staff function and relayed improvements that can influence policy related to decision making. The authors have also developed the MPS model for staff function which can help a company or industry in appraising their own staff and functions which can thereby aid in utilising their potential.     

预测控制等效集结优化策略的研究

优化变量的集结策略是减少预测控制器的在线计算量的一种有效方法. 以往的集结策略大都建立在启发式的基础上,难以保持原预测控制器的性能. 本文从预测控制滚动优化只实际实施第一个控制量的特点出发,提出等效集结的概念,证明了在无约束和有终端零约束的情况下,只要适当选取集结矩阵,可以得到一个与集结前完全等效的集结预测控制器,并给出了确定集结矩阵的算法.     

Compulsive Internet use and workaholism: An exploratory two-wave longitudinal study

Workaholism refers to the uncontrollable need to work and comprises working compulsively (WC) and working excessively (WE). Compulsive Internet Use (CIU), involves a similar behavioural pattern although in specific relation to Internet use. Since many occupations rely upon use of the Internet, and the lines between home and the workplace have become increasingly blurred, a self-reinforcing pattern of workaholism and CIU could develop from those vulnerable to one or the other. The present study explored the relationship between these compulsive behaviours utilizing a two-wave longitudinal study over six months. A total of 244 participants who used the Internet as part of their occupational role and were in full-time employment completed the online survey at each wave. This survey contained previously validated measures of each variable. Data were analysed using cross-lagged analysis. Results indicated that Internet usage and CIU were reciprocally related, supporting the existence of tolerance in CIU. It was also found that CIU at Time 1 predicted WC at Time 2 and that WE was unrelated to CIU. It is concluded that a masking mechanism appears a sensible explanation for the findings. Although further studies are needed, these findings encourage a more holistic evaluation and treatment of compulsive behaviours.     

Orchestrating big data analytics capability for sustainability: A study of air pollution management in China

Under rapid urbanization, cities are facing many societal challenges that impede sustainability. Big data analytics (BDA) gives cities unprecedented potential to address these issues. As BDA is still a new concept, there is limited knowledge on how to apply BDA in a sustainability context. Thus, this study investigates a case using BDA for sustainability, adopting the resource orchestration perspective. A process model is generated, which provides novel insights into three aspects: data resource orchestration, BDA capability development, and big data value creation. This study benefits both researchers and practitioners by contributing to theoretical developments as well as by providing practical insights.     

An evaluation study of a digital library of ideas: Workflow Model and classroom use

The Department of Design Manufacturing and Engineering Management at the University of Strathclyde, Glasgow, UK, has been developing a digital library to support design engineering student learning through the Digital Libraries for Global Distributed Innovative Design Education and Teamwork project (, December, 2007). Previous related studies have observed and analysed how students search for, store, structure and share design engineering information (Grierson et al. in paper presented at the Network Learning Conference, pp. 572–579, 2004; Nicol et al. in Open Learning 20(1):31–49, 2005) and these studies have identified the need for the design and development of a digital library with two system components, which best suit the design process: (i) an informal shared workspace; the ‘LauLima’ Learning Environment and (ii) a repository of more formal searchable and browsable design information; the ‘LauLima’ Digital Library (McGill et al. in Br. J. Educ. Technol. 36(4):629–642, 2005). This paper focuses on the Workflow Model developed to populate the digital library and presents findings from early use of the digital library by students and staff.     

Incorporating sustainable criteria in a dynamic multi-objective recommendation planning tool for a continuous manufacturing process: A dairy case study

The activity of scheduling the production plan with the aim of achieving an optimal criterion has been explored in literature for several manufacturing sectors, in particular when it comes to solving scheduling NP-complete problems. In Dairy Manufacturing, determining an optimum criterion for the scheduling process has numerous internal and external challenges due to the complexity of this environment.The initial stages in the Dairy process are characterised by a continuous manufacturing environment and specific operational issues are observable: interruptions for the accomplishment of Cleaning-In-Place (CIP); a short raw material lifespan which demands a fast processing rate; and the stochastic raw material supply variation. By highlighting these three aspects, a critical trade-off emerges: CIP cycle-times heavily reduce the processing capacity, whereas the raw material processed requires an increase in available capacity due to the impact of seasonality, perishability and stochastic deliveries. Therefore, the scheduling plan must be dynamically readapted based on the current inventory, volume and frequency supplied, CIP cycle-times, maximum equipment running hours and downstream capacities.The aim of this research is to develop an integrated approach for generating equipment schedules under supply uncertainty typically observed in the dairy sector where criteria of sustainability are effortlessly incorporated for an improved decision-making process. An efficient Multi-objective Algorithm (MOA) combining conflicting key performance metrics such as minimising Work-In-Process (WIP), maximising Service Level Agreement (SLA), Utilisation and Energy consumption is proposed.The novelty consists of the ability to dynamically select trade-off criteria and visualise the optimum production plan according to the conditions defined by the decision-maker. The appropriate schedules are presented in a Pareto Frontier graph highlighting the entire non-dominance region according to the volume and frequency supplied. Even though sustainability metrics are usually ignored during production plan definitions, namely when a weak correlation between both environmental and profitable criteria is identified, the results demonstrate improved performance when both sustainable approaches are well explored.     

A study of the relationship between institutional policy,organisational culture and e-learning use in four South African universities

This article investigates the relationship between policy (conceptualised as goals, values and resources), organisational culture and e-learning use. Through both qualitative and quantitative research methods, we gathered data about staff and student perspectives from four diverse South African universities representing a selection of ICT in education policy types (Structured and Unstructured) and organisational cultural types of “collegium, bureaucracy, corporate and enterprise” (McNay, 1995). While our findings show a clear relationship between policy and use of ICTs for teaching and learning, organisational culture is found crucial to policy mediation and the way that e-learning use is embedded within the organisation. We conclude that although a Structured Corporate institutional type enables the attainment of a “critical mass” within e-learning, Unstructured Collegium institutions are better at fostering innovation. Unstructured Bureaucratic institutions are the least enabling of either top down or bottom up e-learning change.     

Assessing the intention to use technology among pre-service teachers in Singapore and Malaysia: A multigroup invariance analysis of the Technology Acceptance Model (TAM)

This study assesses the pre-service teachers’ self-reported future intentions to use technology in Singapore and Malaysia. A survey was employed to validate items from past research. Using the Technology Acceptance Model (TAM) as a research framework, 495 pre-service teachers from Singapore and Malaysia responded to an 11-item questionnaires containing four constructs: intention to use (ITU), attitude towards computer use (ATCU), perceived usefulness (PU), and perceived ease of use (PEU). Structural equation modelling (SEM) was employed as the main method of analysis in this study. A multi-group analysis of invariance was performed on the two samples. The results show that configural and metric invariance were fully supported while scalar and factor variance invariance were partially supported, suggesting that the 11-item measure of the TAM may be robust across cultures and that the factor loading pattern and factor loadings appeared to be equivalent across the cultures examined. While all the paths in the structural model were significant, the variance accounted for in the dependent variable (ITU) was much larger in the Malaysian sample relative to the Singaporean sample.     

Model development in DNDC for the prediction of evapotranspiration and water use in temperate field cropping systems

This paper integrates recent research to improve, test, and verify the process based DeNtrification DeComposition (DNDC) model to estimate evapotranspiration (ET) through a revised FAO Penman–Monteith approach. ET estimates along with biomass and soil water content for spring wheat and corn were improved and found to be in good agreement with the observations at three field sites in eastern Canada (Ottawa). The statistical evaluations (RMSE (mm day⁻¹) and R²) of ET for the newly revised model (0.88 and 0.76 for corn and 0.93 and 0.78 for wheat) showed improvements over DNDC93 (1.95 and 0.22 for corn and 1.62 and 0.09 for wheat) which used the Thornthwaite equation for estimating potential evapotranspiration. In addition, evaluations of water use efficiency for corn and wheat showed good agreement between observations and the modified model. The study demonstrates the inter-dependencies of ET with biomass production and soil/atmosphere water balance.     

Exploring the effects of direct experience on IT use: An organizational field study

Empirical studies have investigated the effect of attitude and behavior on IT acceptance in organizations but yielded ambiguous results. Possibly they have not effectively accounted for the moderating effects of experience gained through direct interaction with the target technology. We examined the moderating effect of the length of direct experience on IT acceptance relationships and constructs. Using multi-group invariance analysis, we demonstrated that relationships between key IT acceptance constructs differed, depending on the user's experience. The incorporation of direct experience can lead to convergent results and contribute to further understanding of the process. We discuss some implications from the knowledge that IT use is a dynamic process and suggest that IT management must account for direct experience in their decision making.     

Using technology to alleviate poverty: use and acceptance of telecenters in rural India

The preponderance of poor people worldwide live in rural areas. Since they cannot afford, and are not educated sufficiently to take full advantage of contemporary knowledge-based technologies, alternative approaches are necessary. A major business model to do so involves setting up a rural telecenter that provides computer and internet technology as a shared model or highly subsidized. Despite the potential and availability of telecenters, research suggests that telecenters have low usage. In this research, we explore the reasons for the low usage of telecenters using a framework for use and acceptance of rural telecenters. The framework we use builds on prominent IT theories and has the following four dimensions: (a) perceived outcomes, (b) perceived effort, (c) social influence, and (d) facilitating factors. We use this framework to formulate six research questions. The study in general has the goal to identify reasons for low use of telecenters and test it with an exploratory study of information and communication technology users and non-users from rural India. Implications are discussed at the village and provider levels. Ramiro Montealegre is the accepting Associate Editor for this article. View all notes     

The use of computers in preschools in Chile: Lessons for practitioners and policy designers

This paper presents the results of survey of the availability and use of computers in a preschool sample in Chile, and compares them with similar results of primary and secondary schools. Results show that although preschools have relatively low access to computers and teachers have relatively low ICT competencies, they declare similar ICT related obstacles and impacts compared to their colleagues in secondary schools. Also, results show that preschool students seem to use computers in the classroom more frequently than their peers in primary and secondary schools and that the activities they implement are focused on developing key curriculum related areas implementing tasks that can be associated to the exercising of key competencies and skills. This specialised use of computers in preschools, which is much more focused than the activities with computers reported by teachers in higher levels, could be explained by the relative low variety of educational software available in these preschools, the availability of the computers in the classroom rather than in labs; the special type of teaching and learning activities implemented at this age level and/or due to the relative lack of teachers' ICT competencies. On the one hand, these results highlight the need for further research, and on the other, it constitutes an interesting lesson for policy designer that tend to advocate for considering computers as “multipurpose” technologies that should be used across subjects, levels and teaching strategies. In this case, computers seem to play a very specific and concrete role in preschools classrooms that, eventually, contributes to improve students' outcomes, which highlights the potential of considering the use of computers, software and other technologies to improve specific subject areas at particular levels while designing ICT in education policies for this age group.     

Beyond basic study skills: The use of technology for success in college

Technology has become a fundamental component of both education and work. Yet regardless of perceived benefits, in many cases students do not use technology effectively. One challenge educators confront is how to motivate students to effectively use the technological mediums provided in their classes. The goal of the current study is twofold: to use the Technology Acceptance Model (TAM) to examine two motivators of behavior, ease of use and perceived need, and to assess how they affect students’ likelihood of effectively using technology. Second, we evaluate how the match between expectations of the use of technology and the actual student use affect actual classroom performance. To test our hypotheses, college students (N = 384) in introductory psychology classes completed a survey. We also obtained the instructor’s perceptions of the need for technology in their class and students’ final class grades. Results showed that ease of use and perceived need of technology were related to the frequency of computer use and intentions to use technology. Additionally, findings suggested that technology use, specifically technology deemed important by the instructor, was related to academic success (i.e., final grade in class).     

Here and now mobile learning: An experimental study on the use of mobile technology

Mobile technology opens the door for a new kind of learning called here and now learning that occurs when learners have access to information anytime and anywhere to perform authentic activities in the context of their learning. The purpose of this study was to investigate the effects of here and now mobile learning on student achievement and attitude. The research questions addressed were (1) Does “Here and Now” mobile learning significantly improve student achievement when compared with Computer based Instruction? (2) Does “Here and Now” mobile learning significantly improve student attitude when compared with Computer based Instruction? (3) Are there differences in student achievement and attitudes when “Here and Now” mobile learning is delivered using a tablet versus ipod? 109 undergraduate students enrolled in preservice instructional design and instructional technology courses at a regional southeastern university participated in the study. Participants took a pretest at the beginning of the study, and then were assigned to one of the versions of an art lesson (CBI version and iPad/iPod version) which were developed using Lectora Inspire incorporating information on five different paintings in the education building. After the lesson, they completed the posttest and an attitude survey. ANOVA was conducted on data obtained from the achievement posttest and on the attitude survey results for the Likert type items (Items 1–12). Analyses on achievement and attitude data revealed positive significant differences. The CBI treatment achieved positive posttest scores on the posttest while the iPad/iPod treatments had positive attitudes. This study has implications for those designing and implementing mobile learning.     

Model assessment of MPCs with control ranges: An industrial application in a delayed coking unit

Poor model quality is one of the most frequent causes of performance deterioration in Model Predictive Controllers. As such, frequent model evaluation and correction is fundamental. Some assessment methods are reported in the literature, but most cannot deal with Model Predictive Controllers (MPCs) without fixed setpoints for controlled variables. Botelho et al. (2015, 2016a, 2016b) proposed a series of methods that include the controller tuning and the applied MPC implementation in the assessment procedure. Their main advantage is setpoint independence. This paper analyzes the application of these methods in an industrial MPC with control ranges. The system studied is an MPC of a fractionating column in a delayed coker unit of a refinery in Brazil. The results demonstrate that the method is capable of correctly quantifying the effect of modeling problems and identifying whether they are related to a model-plant mismatch or unmeasured disturbance.     

Passive Facebook use,Facebook addiction,and associations with escapism: An experimental vignette study

There is relatively little research considering motivations of passive Facebook use. However, research regarding motivations of general Facebook use indicates that people use Facebook to escape – and that escapism may motivate passive Facebook use. Research also suggests that using Facebook to escape is associated with Facebook addiction. Using an experimental vignette design, the present research investigated whether passive Facebook use is motivated by escapism and whether this escape motivation is associated with passive Facebook addiction. A within-participant experimental design using vignettes was used to explore the effect of positivity and, in addition, socialness on passive Facebook use. Addiction to passive Facebook use and perceived effect of passive Facebook use on mood were also assessed. Participants (n = 69) responded to 16 vignettes describing daily life events, as well as responding to a question about passive Facebook use on mood and completing the Bergen Facebook Addiction Scale. Results suggested that individuals did not use Facebook to escape. There was no association between escapism in passive Facebook use and passive Facebook addiction. Social contact had a positive effect on passive Facebook use, and participants perceived passive Facebook use to have no effect on mood. Findings suggest that passive Facebook use is a less effective method of escape than general Facebook use, and reducing individuals’ likelihood of experiencing Facebook addiction symptoms.     

Why people use social networking sites: An empirical study integrating network externalities and motivation theory

Fast-developing social networking sites (SNS) have become the major media by which people develop their personal network online in recent years. To explore factors affecting user’s joining SNS, this study applies network externalities and motivation theory to explain why people continue to join SNS. This study used an online questionnaire to conduct empirical research, and collected and analyzed data of 402 samples by structural equation modeling (SEM) approach. The findings show that enjoyment is the most influential factor in people’s continued use of SNS, followed by number of peers, and usefulness. The number of peers and perceived complementarity have stronger influence than the number of members on perceived benefits (usefulness and enjoyment). This work also ran clustering analysis by gender, which found notable difference in both number of peers and number of members between men and women. The number of peers is an important factor affecting the continued intention to use for women but not for men; the number of members has no significant effect on enjoyment for men. The findings suggest that gender difference also produces different influences. The implication of research and discussions provides reference for SNS operators in marketing and operation.     

System learning approach to assess sustainability and forecast trends in regional dynamics: The San Luis Basin study,Colorado, U.S.A

This paper presents a methodology that combines the power of an Artificial Neural Network and Information Theory to forecast variables describing the condition of a regional system. The novelty and strength of this approach is in the application of Fisher information, a key method in Information Theory, to preserve trends in the historical data and prevent over fitting projections. The methodology was applied to demographic, environmental, food and energy consumption, and agricultural production in the San Luis Basin regional system in Colorado, U.S.A. These variables are important for tracking conditions in human and natural systems. However, available data are often so far out of date that they limit the ability to manage these systems. Results indicate that the approaches developed provide viable tools for forecasting outcomes with the aim of assisting management toward sustainable trends. This methodology is also applicable for modeling different scenarios in other dynamic systems.