Experiences developing architectures for realizing thin‐client diagram editing tools

Diagram‐centric applications such as software design tools, project planning tools and business process modelling tools are usually ‘thick‐client’ applications running as stand‐alone desktop applications. There are several advantages to providing such design tools as Web‐based or even PDA‐ and mobile‐phone‐based applications. These include ease of access and upgrade, provision of collaborative work support and Web‐based integration with other applications. However, building such thin‐client diagram editing tools is very challenging. We have developed several thin‐client diagram editing applications realized as a set of plug‐in extensions to a meta‐tool for visual design environment development. In this paper, we discuss key user interaction and software architecture issues, illustrate examples of interacting with our thin‐client diagram editing tools, describe our design and implementation approaches, and present the results of several different evaluations of the resultant applications. Our experiences will be useful for those interested in developing their own thin‐client diagram editing architectures and applications. Copyright © 2007 John Wiley & Sons, Ltd.     

BCOOPL: Basic concurrent object‐oriented programming language

A small, object‐oriented language is introduced: BCOOPL (Basic Concurrent Object‐Oriented Programming Language). This language is specifically targeted to support component‐oriented programming. The main design goal of BCOOPL was to provide a small, but powerful set of language features that supports the construction of high‐quality components through well‐established software engineering practices, which include the separation of interfaces and implementations, weakly‐coupled objects, and abstraction. A number of design patterns based on these principles is actually built in the language. In particular, the observer, the mediator and the bridge are supported directly. This provides a strong foundation on which higher level component specification languages can be built. BCOOPL has a long research history. Its roots can be traced back to path expressions, and the concurrent object‐oriented programming languages Procol and Talktalk. As a result, BCOOPL only integrates essential language features that blend well and have proven their value in practice. Copyright © 2000 John Wiley & Sons, Ltd.     

Training visual attention in a naturalistic visual environment

The efficiency of training visual attention in the central and peripheral visual field was investigated by means of a visual detection task that was performed in a naturalistic visual environment including numerous, time-varying visual distractors. We investigated the minimum number of repetitions of the training required to obtain the top performance and whether intra-day training improved performance as efficiently as inter-day training. Additionally, our research aimed to find out whether exposure to a demanding task such as a microsurgical intervention may cancel out the effects of training.

Results showed that performance in visual attention peaked within three (for tasks in the central visual field) to seven (for tasks in the periphery) days subsequent to training. Intra-day training had no significant effect on performance. When attention training was administered after exposure to stress, improvement of attentional performance was more pronounced than when training was completed before the exposure. Our findings support the implementation of training in situ at work for more efficient results.

Practitioner Summary: Visual attention is important in an increasing number of workplaces, such as with surveillance, inspection, or driving. This study shows that it is possible to train visual attention efficiently within three to seven days. Because our study was executed in a naturalistic environment, training results are more likely to reflect the effects in the real workplace.     

Social interactions by visual focus of attention in a three‐dimensional environment

In human behaviour analysis, the visual focus of attention (VFOA) of a person is a very important cue. VFOA detection is difficult, though, especially in a unconstrained and crowded environment, typical of video surveillance scenarios. In this paper, we estimate the VFOA by defining the Subjective View Frustum, which approximates the visual field of a person in a three‐dimensional representation of the scene. This opens up to several intriguing behavioural investigations. In particular, we propose the Inter‐Relation Pattern Matrix, which suggests possible social interactions between the people present in a scene. Theoretical justifications and experimental results substantiate the validity and the goodness of the analysis performed.     

Data hiding in grayscale images by dynamic programming based on a human visual model

A new method for data hiding in grayscale images based on a human vision model with distortion-minimizing capabilities is proposed. Each of the eight bit planes of an input grayscale image is viewed as a binary image, into which message data are embedded horizontally. Two optimization techniques, namely, block pattern coding and dynamic programming, are proposed for image distortion minimization. Experimental results show good performs of the proposed method.     

Social facilitation effect in search and decision‐making components of visual inspection

This study aimed to examine the effect of social presence on the performance of the search and decision‐making components of visual inspection. A within‐subject design experiment was conducted. Participants performed easy and difficult search and decision‐making tasks in alone and audience‐present conditions with search time, decision time, decision accuracy rates, and subjective arousal level in both components measured. Results indicated that the presence of an audience shortened (lengthened) the response time in easy (difficult) search and decision‐making components but did not influence decision accuracy rates. The social facilitation intensity in the search component was stronger than that in the decision‐making component. For both components, the performance impairment in difficult tasks was stronger than the performance improvement in easy tasks, and arousal was greater in the audience‐present condition than when working alone. The findings helped clarify the influential mechanisms of the social facilitation effect in visual inspection tasks.     

Optimal design of continuous time irrational filter with a set of fractional order gammatone components via norm relaxed sequential quadratic programming approach

This paper proposes a continuous time irrational filter structure via a set of the fractional order Gammatone components instead of via a set of integer order Gammatone components. The filter design problem is formulated as a nonsmooth and nonconvex infinite constrained optimization problem. The nonsmooth function is approximated by a smooth operator. The domain of the constraint functions is sampled into a set of finite discrete points so the infinite constrained optimization problem is approximated by a finite constrained optimization problem. To find a near globally optimal solution, the norm relaxed sequential quadratic programming approach is applied to find the locally optimal solutions of this nonconvex optimization problem. The current or the previous locally optimal solutions are kicked out by adding the random vectors to them. The locally optimal solutions with the lower objective functional values are retained and the locally optimal solutions with the higher objective functional values are discarded. By iterating the above procedures, a near globally optimal solution is found. The designed filter is applied to perform the denoising. It is found that the signal to noise ratio of the designed filter is higher than those of the filters designed by the conventional gradient descent approach and the genetic algorithm method, while the required computational power of our proposed method is lower than those of the conventional gradient descent approach and the genetic algorithm method. Also, the signal to noise ratio of the filter with the fractional order Gammatone components is higher than those of the filter with the integer order Gammatone components and the conventional rational infinite impulse response filters.     

GLU♮ embedded in C++: a marriage between multidimensional and object‐oriented programming

The embedding of a small but expressive language of multidimensional functional programming in a well known and widely used language of object‐oriented programming leads to the combination of two radically different programming models. In this paper, we formally define the syntax and semantics of GLU^?, which can be thought of as the multidimensional core of Lucid and GLU, and we describe its implementation as a language embedded in C++. With the aid of a few examples, we argue that the marriage of the two programming models is not only compatible and natural, but also that it produces a new and interesting hybrid language. Copyright © 2004 John Wiley & Sons, Ltd.     

Prevention of work‐related musculoskeletal disorders in a chemical plant in Taiwan and a comparison of three assessment tools

Work‐related musculoskeletal disorders (WMSDs) caused by a poor working environment or an improper work design are the most common occupational diseases seriously affecting workers’ health, causing huge economic losses in many countries. Thus, the prevention of WMSDs is considered a priority issue worldwide. In this study, three ergonomics analysis tools and a statistic analysis were used to assess the risk level of exposure to WMSDs and to find improvements for the operations in a chemical plant. The applicability of these tools was also evaluated. Results of the analysis suggest that, to greatly prevent the incidence of WMSDs, a mobile elevating platform should be adopted to adjust the handling height of material bags at 90 cm, allowing the operators to stand in front of them to hold their short or long sides. Among the tools, key indicator methods–manual handling operation methods (KIM‐MHO) have the highest sensitivity.     

The Argus prototype: aggregate use of load modules as a high‐density supercomputer

This paper describes the ARGUS prototype, a high‐density, low‐power supercomputer built from an IXIA network analyzer chassis and load modules. The prototype is configured as a diskless distributed system that is scalable to 128 processors in a single 9U chassis. The entire system has a footprint of 0.25 m² (2.5 ft²), a volume of 0.09 m³ (3.3 ft³) and maximum power consumption of less than 2200 W. We compare and contrast the characteristics of ARGUS against various machines including our on‐site 32‐node Beowulf and LANL's Green Destiny. Our results show that the computing density (Gflops ft⁻³) of ARGUS is about 30 times higher than that of the Beowulf and about three times higher than that of Green Destiny with a comparable performance. Copyright © 2006 John Wiley & Sons, Ltd.     

Professional development to enhance teachers' practices in using information and communication technologies (ICTs) as cognitive tools: Lessons learned from a design-based research study

Technology integration in K-12 classrooms is usually overly teacher-centered and has insufficient impact on students' learning, especially in enhancing students' higher-order cognitive skills. The purpose of this project is to facilitate science teachers' use of information and communication technologies (ICTs) as cognitive tools to shift their practices from traditional teacher-centered methods to constructivist, student-centered ones. This paper describes the outcomes and lessons learned from an application of design-based research (DBR) in the implementation and refinement of a teacher professional development (PD) program that is a key component of the overall project. This DBR study involved 25 middle-school science teachers from 24 schools whose implementation of cognitive tools with their students in science classrooms and virtually through a social networking site were observed over four years. A mixed-methodology was utilized to examine the impact of the cognitive tools intervention on teachers' classroom practices and students' development of new literacy skills. Identifying reusable design principles related to technology integration was another focus of the DBR study. The results revealed teachers' positive changes in their classroom practices by gradually allowing students to take control over the use of technology, and positive impact on students' ICT skills and science learning. Design principles for future professional development programs aimed at preparing teachers to adopt a cognitive tools approach are described.     

Real‐Time Leak Isolation Based on State Estimation with Fitting Loss Coefficient Calibration in a Plastic Pipeline

This paper presents a leak isolation methodology using a fitting loss coefficient calibration. Two stages are considered for this purpose: First, the equivalent straight length (ESL) is fixed by an model‐base observer designed as an extended Kalman filter. Once the leak is detected, the previous observer is stopped and the second system, based on an algebraic observer, is started with the ESL value fixed by the previous observer. Finally, the estimated leak position is recovered in original coordinates since the observer deal with ESL coordinates. In order to tackle the friction variations problem, the so‐called Swamee‐Jain equation is embedded explicitly, instead of a constant parameter as in other studies. The approach assumes only flow and pressure sensors at the ends of the duct. Experimental results with data obtained from a plastic pipeline prototype are presented to assess the method efficiency.     

Fostering self‐regulated learning in a blended environment using group awareness and peer assistance as external scaffolds

Most systems for training self‐regulated learning (SRL) behaviour focus on the provision of a learner‐centred environment. Such systems repeat the training process and place learners alone to experience that process iteratively. According to the relevant literature, external scaffolds are more promising for effective SRL training. In this work, group awareness and peer assistance are used as external scaffolds in the process of training SRL behaviour, enhancing opportunities for self‐reflection and stimulating and encouraging learners. This work further develops a system, called self‐regulated learning with group awareness and peer assistance (SRL‐GAPA). Experimental results reveal that SRL‐GAPA provides significantly more participation in online training tasks and learning activities, better SRL behaviour and better learning achievement than the traditional SRL system (i.e,, a learner‐centred environment). The SRL‐GAPA benefited poorly self‐regulated learners more than highly self‐regulated students. Some implications of this finding are discussed.     

Improvement strategies for the tools and techniques of quality improvement: Utilization of a performance evaluation matrix in the taiwanese high‐tech industry

This study integrates importance–performance analysis (IPA) and Slack's IPA matrix to provide a more comprehensive performance‐evaluation matrix for prioritizing improvement actions with regard to the tools and techniques of quality improvement. The study undertakes a review of the literature to identify the tools and techniques most widely used by high‐tech businesses in Taiwan. Following a survey of 394 managers and technicians, these tools and techniques are then placed on the integrated performance‐evaluation matrix to determine appropriate priorities for improvement actions. The study finds that “new seven” total quality management tools are used less often than “old seven” total quality management tools, and that education, training, and the efficient use of corporate resources are required to improve the frequency of utilization and the performance of the tools and techniques of quality improvement. © 2011Wiley Periodicals, Inc.