Feniosky Peña-Mora

An experience in collaborative software engineering education

Large-scale software development requires the interaction of specialists from different fields who must communicate their decisions and coordinate their activities. As global software development becomes mainstream, software engineers face new challenges for which they have received little or no training. To help a new generation of software developers better understand the industrys globalization and familiarize them with distributed, collaborative development, we designed a course entitled the Distributed Software Engineering Laboratory. In the class, pairs of students from different countries work as a virtual organization overseeing the whole software development process. We describe the lessons we have learned in this course and propose a framework useful in dealing with some of the difficulties participants face.

CAIRO: a concurrent engineering meeting environment for virtual design teams

Abstract This paper presents the software architecture for a next generation concurrent engineering environment that helps geographically separated designers and engineers to collaborate effectively. The paper highlights research in computer-supported collaboration work (CSCW) based on various models of group interaction, social communication theory, negotiation theory and distributed artificial intelligence concepts. The paper describes CAIRO (Collaborative Agent Interaction and synchROnization) system, a distributed conferencing architecture for managing designers and engineers in a distributed design meeting. The CAIRO system allows designers and engineers to work together in virtual teams by supporting multi-media interactions over computer networks. CAIRO aids the concurrent engineering effort by relaxing the physical, temporal and organizational constraints experienced in traditional design meeting environments. CAIRO provides both media synchronization, i.e. ensuring that all information exchanged between users is synchronized, and agent synchronization, i.e. ensuring effective structuring and control of a distributed conference. This paper also details the prototype CAIRO system with a detailed example, illustrating its use in concurrent design settings.

Sustainability analysis of earthmoving operations

Emissions from construction equipment are the main contributor of environmental impacts from construction processes, and mitigating these impacts is an important aspect of operations design and planning. To this end, emission estimation models play an important role in environmental management of construction operations. This paper presents an emission model that integrates with discrete-event simulation (DES) for more accurate emission estimates from construction operations compared to existing models. The paper also presents a case study which analyzes sustainability of an earthmoving operation, to demonstrate the application of DES for estimating emissions.

Conflict mitigation system for collaborative engineering

Large-scale engineering projects typically involve many different types of professionals who must interact and communicate with one another. This interaction produces conflicts that need to be resolved. A framework is presented in which the rationale used in a collaborative design environment for designing an artifact is also used for conflict mitigation. The framework contains mechanisms for checking interactions and prompting hypotheses about the reasons for the interactions. These hypotheses, once verified by the designers, improve conflict resolution by assisting them in coordinating and negotiating conflicts. This, in turn, enhances communication during the design process and consequently increases productivity in the engineering industry.

Mobile Ad Hoc Network-Enabled Collaboration Framework Supporting Civil Engineering Emergency Response Operations

This paper presents an information-technology-based collaboration framework that facilitates disaster response operations. The collaboration framework incorporates a web collaboration service, radio frequency identification (RFID) tags, a building blackbox system (BBS), a geo-database, and a geographic information system (GIS). Through the integration of these technologies, the framework provides a collaboration medium for first responders, including civil engineers, to cohesively respond to disasters. Access to critical building information, such as construction documents, through the BBS supports assessments of building integrity during disaster response. Building assessment information is stored on RFID tags, which are accessible to first responders through digital devices via a wireless ad hoc network. With on-site assessment information shown on a digital map, decision makers locate, collect, and distribute critical resources through the GIS to first responders. In addition, the decision makers at distributed locations evaluate the incident through discussion sessions, hosted by the web collaboration environment, for integrated decision making. Test-bed simulations for the framework have been carried out with encouraging results at the training ground of the Illinois Fire Service Institute.

Augmenting design patterns with design rationale

Present-day software applications are increasingly required to be reuse-conscious in terms of the operating platforms, topology, and evolutionary requirements. Traditionally, there has been much difficulty in communicating specialized knowledge like design intents, design recommendations, and design justifications in the discipline of software engineering. This paper presents a methodology based on the combination of design rationale and design patterns to design reusable software systems. Design rationale is the representation of the reasoning behind the design of an artifact. Design patterns are descriptions of communicating objects and classes that are customized to solve a general design problem in a particular context. The paper details the use of an explicit software development process to capture and disseminate the specialized knowledge (i.e., intents, recommendations, and justifications) that augments the description of the cases in a library (i.e., design patterns) during the development of software applications by heterogeneous groups. The importance of preserving and using this specialized knowledge has become apparent with the growing trend of combining the software development process with the product (i.e., software code). The importance of codifying corporate memory in this regard is also important considering the changing nature of the workplace, where more people are on contract. The information on how and why a software code was developed becomes essential for efficient and smooth continuity of the present software project as well as for reusing the code in future projects. It has become essential to capture the design rationale to develop and design software systems efficiently and reliably. The software prototype developed using the combined methodology will be used as a part of an integrated design environment for reusable software design. This environment supports collaborative development of software applications by a group of software specialists from a library of building block cases represented by design patterns.

Empirical assessment of a RGB-D sensor on motion capture and action recognition for construction worker monitoring

BackgroundFor construction management, data collection is a critical process for gathering and measuring information for the evaluation and control of ongoing project performances. Taking into account that construction involves a significant amount of manual work, worker monitoring can play a key role in analyzing operations and improving productivity and safety. However, time-consuming tasks involved in field observation have brought up the issue of implementing worker observation in daily management practice.MethodsIn an effort to address the issue, this paper investigates the performances of a cost-effective and portable RGB-D sensor, based on recent research efforts extended from our previous study. The performance of an RGB-D sensor is evaluated in terms of (1) the 3D positions of the body parts tracked by the sensor, (2) the 3D rotation angles at joints, and (3) the impact of the RGB-D sensor’s accuracy on motion analysis. For the assessment, experimental studies were undertaken to collect motion capture datasets using an RGB-D sensor and a marker-based motion capture system, VICON, and to analyze errors as compared with the VICON used as the ground truth. As a test case, 25 trials of ascending and descending during ladder climbing were recorded simultaneously with both systems, and the resulting motion capture datasets (i.e., 3D skeleton models) were temporally and spatially synchronized for their comparison.ResultsThrough the comparative assessment, we found a discrepancy of 10.7 cm in the tracked locations of body parts, and a difference of 16.2 degrees in rotation angles. However, motion detection results show that the inaccuracy of an RGB-D sensor does not have a considerable effect on action recognition in the experiment.ConclusionsThis paper thus provides insight into the accuracy of an RGB-D sensor on motion capture in various measures and directions of further research for the improvement of accuracy.

A system dynamics model for assessing the impacts of design errors in construction projects

Abstract Design errors leading to rework and/or design changes are considered to be the primary contributor to schedule delays and cost overruns in design and construction projects. While design errors are deemed prevalent, most design and construction firms do not measure the number of errors they create, thereby having limited knowledge regarding their mechanism to undermine project performance. To address this, a system dynamics model has been developed to capture the dynamics of design errors and systematically assess their negative impacts. This paper reports on the development of the model, and its application to a university building project. The results indicate that design errors can significantly delay project schedule in spite of continuous schedule recovery actions taken by construction managers. The case study also shows that schedule pressure can propagate the negative impact of design errors to numerous construction activities, including those that are not directly associated with the errors. Finally, the case study confirms that the developed model can more rigorously assess the negative impact of design errors, which is often underestimated by practitioners. Based on these results, it is concluded that the developed model can assist project managers in better understanding the dynamics of design errors and recovering delayed schedule, particularly under schedule pressure.

Monitoring changes of 3D building elements from unordered photo collections

This paper proposes an automated method for monitoring changes of 3D building elements using unordered photo collections as well as Building Information Models (BIM) that pertain information about geometry and relationships of elements. This task is particularly challenging as existing construction photographs are taken under different lighting and viewpoint conditions, are uncalibrated and extremely cluttered by equipment and people. Given a set of these images, our system first uses structure-from-motion, multi-view stereo, and voxel coloring algorithms to calibrate cameras, reconstruct the construction scene, quantize the scene into voxels and traverse and label the voxels for observed occupancy. The BIM is subsequently fused into the observed scene by a registration-step and voxels are traversed and labeled for expected visibility. Next, a machine learning scheme built upon a Bayesian model is proposed that automatically detects and tracks building elements in presence of occlusions. Finally, the system enables the expected and reconstructed elements to be explored with an interactive, image-based 3D viewer where construction progress deviations are automatically color-coded over the BIM. We present promising results on several challenging construction photo collections under different lighting conditions and sever occlusions.

CAIRO: a system for facilitating communication in a distributed collaborative engineering environment

Abstract Conference management is a critical component of a collaborative engineering effort. This paper describes cairo (Collaborative Agent Interaction control and synchROnization system), a system for managing participants in a distributed conference. We have drawn from various models of group interaction and social communications theory in order to develop cairo . The cairo system provides both media synchronization, i.e. insuring that all information conveyed from one participant to another is synchronized, and agent synchronization, i.e. insuring effective structuring and control of a distributed conference.