Software engineering education should balance theoretical concepts with practical application, and many curricula adopt practical skills training organised around project-based learning. In this context, the choice of target software systems becomes critical to the success of the learning experience. Traditional software engineering modules in higher education often provide projects with clearly defined requirements, removing much of the authentic ambiguity found in real world settings - ambiguity that requires engineers to define problems, navigate shifting requirements, and adapt to unforeseen changes. To address these limitations, we introduced an ideation process into our project-based learning approach. This process helps students cope with uncertainty and develop skills needed to operate in scenarios that more accurately mirror professional practice. Analysis of student feedback from reflective reports shows strong appreciation for this approach, particularly regarding guided learning, inclusion of students with diverse backgrounds and skill sets, improved skills development in negotiation, pitching, and presenting, and a stronger sense of project ownership. We also encountered challenges, including balancing project workload with existing commitments, ensuring fairness when the selected project theme does not match available resources, and distributing workload equitably within teams. As future work, we aim to strengthen the ideation process by providing clearer guidance on project scoping and workload estimation.

Digital health technology utilizing wearables, IoT and mobile devices has been successfully applied in the monitoring of numerous diseases and conditions. However, intervention, in response to monitored data, is yet to benefit from technological support and continues to follow a traditional point-of-care delivery model by providers and health professionals. Mental health is an example of a critical health area in dire need for technology solutions to enable timely, effective and scalable interventions. This is especially the case with an increasing prevalence of mental health conditions and a declining capacity of the healthcare professional workforce. Numerous studies reveal the potential for peer support groups as an effective, scalable, cost-effective, first-line of response in mental health interventions. Peer support helps participants, at low and moderate risk, better understand their diseases or conditions and empowers them to take control of their own health. Peer support interactions also seems to inform health professionals with insights and intricate knowledge, making it effectively a learning health system. This paper proposes a software architecture to better enable "peer-sourcing". We present related work and show how the proposed architecture might draw similarity to and differences from crowd-sourcing architectures. We also present a study in which we interacted with service users (mental health patients) and mental healthcare professionals to better understand and elicit the key requirements for the software architecture.

The prevalence of design problems may cause re-engineering or even discontinuation of the system. Due to missing, informal or outdated design documentation, developers often have to rely on the source code to identify design problems. Therefore, developers have to analyze different symptoms that manifest in several code elements, which may quickly turn into a complex task. Although researchers have been investigating techniques to help developers in identifying design problems, there is little knowledge on how developers actually proceed to identify design problems. In order to tackle this problem, we conducted a multi-trial industrial experiment with professionals from 5 software companies to build a grounded theory. The resulting theory offers explanations on how developers identify design problems in practice. For instance, it reveals the characteristics of symptoms that developers consider helpful. Moreover, developers often combine different types of symptoms to identify a single design problem. This knowledge serves as a basis to further understand the phenomena and advance towards more effective identification techniques.

We have been generally successful for transferring software engineering knowledge to industry through various forms of education. However, many challenges in software engineering training remain. A key amongst these is how best to energise software engineering education with real-world software engineering practices. This paper describes our experience of delivering a radically different approach based on the notion of a Software Design Studio. The Software Design Studio is both a lab for students engaged in conceiving, designing and developing software products as well as an approach for teaching software engineering in the lab which emphasizes practical hands-on work and experimentation. The feedback on the Software Design Studio -- from both staff and students -- has been outstanding. Although the programme is designed as a small, elite programme there is interest to see if the teaching methods can be transferred across to the much larger undergraduate programme in Computer Science. In this paper, we provide a detailed description of how our studio works in practice so that others, thinking of tak-ing a studio or studio-inspired approach, can use in designing their own courses.

SUMMARY Establishing explicit mappings between features and their implementation elements in code is one of the critical factors to maintain and evolve software systems successfully. This is especially important when developers have to evolve program families, which have evolved from one single core system to similar but different systems to accommodate various requirements from customers. Many techniques and tools have emerged to assist developers in the feature mapping activity. However, existing techniques and tools for feature mapping are limited as they operate on a single program version individually. Additionally, existing approaches are limited to recover features on demand, that is, developers have to run the tools for each family member version individually. In this paper, we propose a cohesive suite of five mapping heuristics addressing those two limitations. These heuristics explore the evolution history of the family members in order to expand feature mappings in evolving program families. The expansion refers to the action of automatically generating the feature mappings for each family member version by systematically considering its previous change history. The mapping expansion starts from seed mappings and continually tracks the features of the program family, thus eliminating the need of on demand algorithms. Additionally, we present the MapHist tool that provides support to the application of the proposed heuristics. We evaluate the accuracy of our heuristics through two evolving program families from our industrial partners. Copyright © 2013 John Wiley & Sons, Ltd.

The depth information in multiview 3D video sequences are mainly utilized to synthesize new video sequences at virtual view points. Decoded depth maps, however, have typical coding artifacts such as blocking noise according to the compression ratio. Furthermore, depth maps are even resized to reduce the size of compressed bitstreams. Defects in depth maps degrade the quality of synthesized view. This paper proposes a depth resampling method as post processing for encoding/decoding of mixed resolution multiview 3D videos. Different filtering approaches are applied according to the type of depth map. Gray scale dilation filter is applied to graphics depth data to directly remove artifact in synthesized view, and segmentation based filter is applied to estimated or measured depth data to enhance edge and to reduce the compression noise. Experimental result using MPEG reference software shows that the BD bitrate gain in terms of synthesized PSNR is -5.69% for 7 test sequences.

Since its rise to general awareness and popularity starting close to two decades ago, the concept of software product lines has taken the center stage in the software reuse community. After more than four decades of research into effective and efficient reuse of software inside the four walls of the organization, and countless initiatives, software product lines presented an approach that has proven to provide real productivity improvements in the development cost of software intensive products. This has allowed companies to increase their product portfolio with an order of magnitude, to allow for much higher degrees of configurability by customers, facilitated common look-and-feel across a wide product population and enabled companies to be more innovative by decreasing the cost of new product experiments. It achieved this by broadening the scope of study from technology to include process, business strategy and organizational aspects. Successful product lines address all aspects relevant to the organization and then adopt and institutionalize the approach in the company. This special issue features eight papers from the 14th Software Product Line Conference (SPLC 2010). SPLC provides an institution and the premier meeting place for the software product line community. In particular, SPLC 2010 was held in Jeju, South Korea, and the accepted papers covered various areas of software product line engineering including product line contexts, variability management, formal approaches, product validation, and feature modeling. We invited eight top quality papers and they were significantly improved and extended for this special issue.

3D video services can be supported by a multi-view video plus depth (MVD) format. The MVD format is a promising approach for realizing a natural 3D scene efficiently with a small amount of data, because it can generate virtual views for arbitrary view-points at receiver sides. Many researchers have investigated relation between a texture image and its corresponding depth map in the MVD format. In this paper, we analyze their mode correlation and then propose a fast mode decision algorithm for depth image coding based on the analysis. Experimental results indicate that the proposed method drastically reduces its encoding time with negligible quality losses in both the reconstructed depth maps and the rendered synthetic texture images.

In this paper, we present a novel depth map coding scheme to improve coding efficiency. For this purpose, we develop an adaptive nonlocal range filter that restores the coded depth map by the noise suppression. Unlike the previous works that adapted the original nonlocal means algorithm or the original bilateral filter to the depth data, our approach is fundamentally different in that the nonlocal principle in the color data and the range filter in the depth map are taken into account, respectively. Furthermore, the optimal fall-off parameters that control the smoothing strength are determined at the encoder and the restoration is performed with the optimal fall-off parameter at the decoder. This technique allows for the strong slope restoration at the boundary and the noise smoothing near the boundary. Finally, the depth map coding that performs the new approach is implemented and this results in 9.71%(rate-distortion evaluation) and 8.71%(rate-quality evaluation) BD-bitrate reduction on average when compared with 3DV HEVC.

Depth video coding is one of the key techniques to realize the three-dimensional (3D) video system. The depth video is spatially high correlated compared to its corresponding color video in general. In this paper, we propose a high priority intra coding method for depth video coding to efficiently reduce the spatial redundancy. The proposed intra mode is designed based on the intra 16×16 mode. It exploits the derived prediction direction from the adjacent neighboring pixels and does not encode any residual data. The proposed intra mode is allowed I slice as well as P and B slices. It is newly defined for I slice as skip mode and replaced with the skip or direct modes for P and B slices. By the experiments on JMVC 8.2, we confirm that the proposed high priority intra mode reduces about 14.63% bit rate compared to JMVC 8.2 at the same rendering quality.

This paper focuses on sharpening boundaries in depth maps for multi-view video coding. Artifacts around boundaries degrade the quality of synthesized images. In order to encounter this problem, after applying the deblocking filter for each frame, we create a binary edge map and find the location of blocks that need to be altered. Subsequently, we apply a boundary sharpening filter which uses pixel frequency, similarity, and closeness as sub-costs. This filter is only applied to blocks which are near edges. Experimental results exhibit much more visual comfort level in synthesized images compared to when JMVC was used.

Safety critical systems (e.g., an avionics control system for safe flight) are often required to achieve certification under pre-established standards (e.g., DO-178B for software considerations in airborne systems and equipment certification). We have been working with our industrial partner for the last three years to develop product line assets for their avionics software product line (SPL) and, recently, we encountered two major challenges regarding certification. Firstly, an individual product must be certified, but each may require a different certification level: there might be variations in the certification requirements according to specific system usage contexts. Secondly, certification involves not only product but also process, as standards such as DO-178B also assess the quality of the development process. In this paper, we propose to include a certification view during feature modelling to provide a better understanding of the relationships between features and a certification level required for each product. The experience of introducing certification into the design model of an Unmanned Aerial Vehicle (UAV) SPL is presented to illustrate some key ideas. We also describe the lessons we have learned from this experience.

A program family might degenerate due to unplanned changes in its implementation, thus hindering the maintenance of family members. This degeneration is often induced by feature code that is changed individually in each member without considering other family members. Hence, as a program family evolves over time, it might no longer be possible to distinguish between common and variable features. One of the imminent activities to address this problem is the history-sensitive recovery of program family's features in the code. This recovery process encompasses the analysis of the evolution history of each family member in order to classify the implementation elements according to their variability nature. In this context, this paper proposes history-sensitive heuristics for the recovery of features in code of degenerate program families. Once the analysis of the family history is carried out, the feature elements are structured as Java project packages; they are intended to separate those elements in terms of their variability degree. The proposed heuristics are supported by a prototype tool called RecFeat. We evaluated the accuracy of the heuristics in the context of 33 versions of 2 industry program families. They presented encouraging results regarding recall measures that ranged from 85% to 100%; whereas the precision measures ranged from 71% to 99%.

This workshop on services, clouds, and alternative design strategies for variant-rich software systems brings together researchers and practitioners that are interested in or have been working on variant-rich software systems.

Since advanced 3D video systems employ depth information to support free-viewpoint navigation and comfortable 3D video viewing, efficient depth map coding is necessary for future 3D video systems. Most residual data in depth map coding are generated along abrupt depth discontinuities, represented by near-zero and high-magnitude values. In this paper, we model the residual data with two representative values calculated by the K-means clustering method and send them to the decoder by skipping transformation. After best mode decision, we applied the proposed method to a block containing residual data, and then we send the quantized representative values to decoder if its coding rate is less than the conventional best mode. By conducting INTRA only coding, -20.32% bit saving was achieved.

In general, a depth image in a multi-view video plus depth (MVD) format is employed as additional data to synthesize a virtual texture view. In this paper, the proposed method generates a virtual depth view through depth view synthesis and then adaptively uses the synthesized virtual depth view during encoding, according to an evaluation on effect of the synthesized depth view on the multi-view rendering quality. Experimental results demonstrate that the proposed method significantly reduces a depth image coding bit rate without degrading the rendering quality.

In this paper, we present a new depth map coding scheme to improve coding efficiency. For this purpose, we developed an adaptive bilateral filter that restores the coded depth maps in accordance with the estimated noise variance. More specifically, each pixel is classified in such a way that the distortion cost is minimized and is restored depending on local noise level. The restored picture is used for the motion-compensated prediction of future pictures. This can improve coding efficiency. In particular, we propose classifying each pixel based on the optimal threshold and selecting the optimal fall-off parameter, which makes the bilateral filter more powerful. Finally, video coding that performs the new approach was implemented and this resulted in 11.4% (rate-distortion sense) and 12.0% (rate-quality sense) BD-bitrate reduction on average in FRExt Profile when compared with H.264/MVC.

To improve rendered view quality in a 3-D video system, we propose to encode and transmit depth transition data, which represents, for each pixel in a frame, the location in between two existing views where the depth corresponding to that pixel changes. Given the highly localized and non-linear characteristics of rendered view distortion, it is possible to achieve better coding performance by providing this depth transition data only for subjectively important regions. In this paper, a method to apply the depth transition data to the view rendering procedure is proposed. Experimental results verify that improvements in subjective quality can be achieved by the proposed method.

This work proposes a new intra prediction coding scheme for depth map images used in view interpolation. The main goal is to design a prediction scheme which can reduce the prediction error energy in blocks with arbitrary edge shapes. This will reduce the rate needed to encode such blocks while also eliminating some of the annoying artifacts caused by quantization. Since depth maps typically consist of smooth regions separated by edges, we find it sufficient to design prediction schemes which can make effective use of edge information. Working from the intra prediction framework in H.264, we provide a graph representation of pixels in a block and pixels from previously coded blocks and construct an edge-aware prediction scheme based on this. We also employ existing rate-distortion (RD) optimization methods to further improve the coding performance. Our proposed methods reduce the bit rate for depth maps by up to 29% for a fixed interpolated PSNR for some sequences.

The objective of this work is to develop a new 3-D video coding system which can provide better coding efficiency with improved subjective quality as compared to existing 3-D video systems. We have analyzed the distortions that occur in rendered views generated using depth image based rendering (DIBR) and classified them in order to evaluate their impact on subjective quality. As a result, we found that depth map coding distortion leads to “erosion artifacts” at object boundaries, which lead to significant degradation in perceptual quality. To solve this problem, we propose a solution in which depth transition data is encoded and transmitted to the decoder. Depth transition data for a given pixel indicates the camera position for which this pixel's depth will change. A main reason to consider transmitting explicitly this information is that it can be used to improve view interpolation at many different intermediate camera positions. Simulation results show that the subjective quality can be significantly improved by reducing the effect of erosion artifacts, using our proposed depth transition data. Maximum PSNR gains of about 0.5 dB can also be observed.

A novel intra coding scheme is proposed to improve coding performance in intra pictures of H.264/AVC. The proposed method generates two sub-images, which are defined as a sampled image and a prediction error image in this paper, from an original image, and then encodes them separately. Especially, in an intra prediction process of encoding, the sampled image employs the original intra prediction modes, while the prediction error image uses newly defined four intra prediction modes. Experimental results demonstrate that the proposed method achieves significantly higher intra coding performance and reduces encoding complexity with the smaller number of a rate-distortion (RD) cost calculation process, as compared with the original intra coding method of H.264/AVC.

In this work a new set of edge-adaptive transforms (EATs) is presented as an alternative to the standard DCTs used in image and video coding applications. These transforms avoid filtering across edges in each image block, thus, they avoid creating large high frequency coefficients. These transforms are then combined with the DCT in H.264/AVC and a transform mode selection algorithm is used to choose between DCT and EAT in an RD-optimized manner. These transforms are applied to coding depth maps used for view synthesis in a multi-view video coding system, and provides up to 29% bit rate reduction for a fixed quality in the synthesized views.

Service Orientation (SO) is a relevant promising candidate for accommodating rapidly changing user needs and expectations. Adopting SO in practice for real software and system development, however, has uncovered several chal-lenging issues, such as how to identify services, determining configurations of services that are relevant to users' current context, and maintaining system integrity after configuration changes. In this paper, we propose a method that addresses these issues by adapting a feature-oriented product line engineering approach. Our method is based on the feature analysis technique that enables us to identify services of a service oriented system. The method is notable in that it guides developers to identify services at the right level of granularity, to map users' context to relevant ser-vice configuration, and to maintain system integrity in terms of invariants and pre/post conditions of services. We also propose a heterogeneous style based architecture model for developing such systems.

Consensual and hierarchical approaches are developed for the classification of remotely sensed multispectral images. The proposed method consists of preprocessing of input patterns, generating multiple classification results by hierarchical neural networks, and a combining scheme to generate a consensus of multiple classification results. Transformations of input patterns by random matrices and nonlinear filtering are used for preprocessing. By varying the input patterns, the multiple classification results are generated with sufficiently independent errors by using a single type of classifier. This helps to improve classification performance when the multiple classification results are combined. Hierarchical neural networks involve the use of successive classifiers which are tuned to reduce the remaining errors to increase the classification performance. This structure includes detection schemes to decide whether successive classifiers are utilized for each input. Consensual and hierarchical approaches generate more reliable and accurate results based on group decision.

Dynamic product reconfiguration refers to making changes to a deployed product configuration while a system is running. Recently, there have been increasing demands for dynamic product reconfiguration in various application areas (e.g., ubiquitous computing, self-healing systems, etc.); however, most product line engineering methods in the literature have focused on the development of reusable core assets for statically configured products. In this paper, we propose a feature-oriented approach to develop dynamically reconfigurable core assets. This approach takes feature binding analysis results as a key design driver for identifying and managing variation points of dynamically reconfigurable products. We also provide a conceptual model for a reconfigurator, which monitors and manages product reconfiguration at run time. The method is illustrated with a home service robot product line example

Typical robot development requires that hardware be mostly functional before significant software development begins. Utilizing virtual prototype of hardware and its environment can reduce development time and manufacturing cost. Virtual prototyping is, however, a highly challenging task requiring in-depth knowledge in many disciplines. Few of simulation tools developed to alleviate this difficulty fully manage the complexity caused by the fact that developer must design and manage form (physical shape), function, and behavior altogether incrementally. Also, such simulation tools often do not support co-development of the target software and its test environment from requirements analysis to implementation. In this paper, we present our experience of developing a virtual prototype of Samsung Home Robot (SHR) with Samsung Advanced Institute of Technology (SAIT) using ASADAL/OBJ. Virtual prototyping in ASADAL/OBJ enables incremental co-development of both target system and its test environment in an object-oriented way. Furthermore ASADAL/OBJ facilitates concurrent development of form, behavior, and function. These features increase productivity as well as confidence through incremental refinement and validation. We give a brief background on the ASADAL/OBJ framework, then illuminate our experience of developing a virtual prototype of SHR.

With the advances of robotics, computer science, and other related areas, home service robots attract much attention from both academia and industry. Home service robots present interesting technical challenges to the community in that they have a wide range of potential applications, such as home security, patient caring, cleaning, etc., and that the services provided by the robots in each application area are being defined as markets are formed and, therefore, they change constantly.Without architectural considerations to address these challenges, robot manufacturers often focus on developing technical components (e.g., vision recognizer, speech processor, and actuator) and then attempt to develop service robots by integrating these components. When prototypes are developed for a new application, or when services are added, modified, or removed from existing robots, unexpected, undesirable, and often dangerous side-effects, which are known as feature interaction problem, happen frequently. Reengineering of such robots can make a serious impact in delivery time and development cost.In this paper, we present our experience of re-engineering a prototype of a home service robot developed by Samsung Advanced Institute of Technology. First, we designed a modular and hierarchical software architecture that makes interaction among the components visible. With the visibility of interactions, we could assign functional responsibilities to each component clearly. Then, we re-engineered existing codes to conform to the new architecture using a reactive language Esterel. As a result, we could detect and solve feature interaction problems and alleviate the dificulty of adding or updating components.

Architecture evaluation to confirm that the quality requirements were satisfied by the developed software architecture is one of the most important issues in architecture-based software development approaches. Architecture Tradeoff Analysis Method (ATAM) is one such method, and the scenario-based quality requirement elicitation is an important factor for applying the method. We applied the method to factory-process-controlling systems with our industrial partner and this paper presents difficulties for quality requirement elicitation and a strategy to address these problems.

PBX (private branch exchange) systems are evolving rapidly due to fast expanding services, ever-changing communication technology, continuously evolving standards, and diverse communication laws and standards in different countries. As new features are added continuously, the detection of feature interaction problems early in the development lifecycle and the resolution of these problems through adaptable software are difficult challenges which all PBX software engineers face. A feature-oriented reuse method (FORM), introduced in this paper, concentrates on analyzing and modeling commonalities and differences in applications of a given domain in terms of features. The analysis results are then used for both the analysis of feature interactions and the engineering of domain-oriented software with a high level of adaptability (and reusability). We found that FORM facilitates the analysis of feature interactions and the variability (and commonality) of software before engineering and implementation begin. By understanding the variability, adaptability and reusability could be built into the software. The software architecture and modules are implemented based on information hiding and encapsulation principles and could easily accommodate new features that have not been considered in the initial feature analysis.

Incorporating a high level of adaptability and reusability into software is one challenge that all software engineers face. PBX (Private Branch Exchange) is one such system that requires a high level of adaptability and reusability because of rapidly expanding service features, ever changing communication technology, continuously evolving standards and diverse communication laws and standards in different countries. The software engineering community has made various efforts to address the problem of enhancing software adaptability and reusability. As a result, many programming concepts, such as information hiding, encapsulation, object orientation, abstract data type and modularization, have been developed. Although adequate application of these principles requires the domain or program family perspective, most methods, so far, have been oriented toward developing a single application. FORM (Feature-Oriented Reuse Method), the domain-based software reuse method applied in this paper, concentrates on analyzing and modeling commonalities and differences in applications of a given domain and using the analysis results to develop domain-oriented architectures and software components. The model that captures commonalities and differences is called the ‘feature model’ and it is used for both the engineering of reusable domain artifacts and the development of actual application software with reusable artifacts. We found that FORM facilitates analysis of variability, as well as commonality, of software before the start of engineering and implementation. With this understanding, adaptability and reusability can be built into software. Also, feature modeling has been found to be an effective method for identifying objects. Copyright © 1999 John Wiley & Sons, Ltd.