Service feature modeling: modeling and participatory ranking of service design alternatives

The design of software-intensive service systems involves and affects numerous stakeholders including software engineers, legal and business experts as well as a potentially large number of consumers. In consequence, the challenge arises to adequately represent the interests of these groups with respect to service design decisions. Specifically, shared service design artifacts and participatory methods for influencing their development in consensus are required, which are not yet state of the art in software service engineering. To this end, we present service feature modeling. Using a modeling notation based on feature-oriented analysis, our approach can represent and interrelate diverse service design concerns and capture their potential combinations as service design alternatives. We further present a method that allows stakeholders to rank service design alternatives based on their preferences. The ranking can support service engineers in selecting viable alternatives for implementation. To exploit this potential, we have implemented a toolkit to enable both modeling and participative ranking of service design alternatives. It has been used to apply service feature modeling in the context of public service design and evaluate the approach in this context.     

Different metabolic and absorption patterns of betaine in response to dietary intake of whole-wheat grain, wheat aleurone or rye aleurone in catheterized pigs

In the present study, a novel method of measuring the uptake of nutrients by 1H NMR spectroscopy was performed to determine dietary effects. Six pigs catheterized in the portal vein and mesenteric artery were fed breads made from whole-wheat grain (WWG), wheat aleurone flour (WAF; 19?% aleurone of bread) or rye aleurone flour (RAF; 15?% aleurone of bread) in a repeated 3?×?3 crossover design. Three meals were provided daily (at 0, 5 and 10?h), and each period comprised of 1?week. Portal and arterial blood samples were collected at fasting (?30?min) on day 4–7, and on day 7, pooled blood samples were collected at 0–2.5, 2.5–5, 5–7.5 and 7.5–10?h after first (0?h) daily meal. Using the arterial-venous difference and ANOVA–simultaneous component analysis, plasma betaine was found to accumulate during the experimental period. On day 7, plasma betaine concentrations was 20–40?% higher than when feeding the WAF diet compared with RAF and WWG (P?=?0.001), whereas the content of betaine in the WAF diet was about twice as high. The arterial-venous difference showed a tendency (P?=?0.078) for the diet–time interaction of betaine absorption in the absorption phases but there was no diet effect (P?=?0.31), which indicates a steady-state absorption has been reached on day 7. Furthermore, high plasma betaine levels correlated with low plasma creatine of endogenous origin. In conclusion, the explorative method revealed that the plasma concentration and absorption of betaine were differentially modified by the diets.     

Landsat approaches to map agro-pastoral farming in the wetlands of southern Sudan

Machine-learning algorithms (MLA) are coming of age within satellite remote sensing (SRS). This study compares the performance of a number of MLAs with more traditional indices and algorithms to map annual agro-pastoralist farming activity in southern Sudan. Two Landsat images from the early dry season 2014 and 2015 were analysed thoroughly and evaluated by interpretation of farming cover from very high resolution (VHR) images on Google Earth (GE). Traditional SRS indices based upon red and near infrared (NIR) bands used for monitoring rangelands did not perform well for the wet rangeland conditions compared to the use of blue and shortwave infrared (SWIR) bands. The species distribution model programme, MaxEnt, was used to produce a continuous farming activity indices using only Landsat-derived variables. Compared to other SRS classification approaches, maximum entropy (MaxEnt) showed the best overall performance to map farming activity followed by classification tree analysis (CTA). Overall mapping agreement >95.0% was reached for most methodologies, with MaxEnt showing very high mapping agreement (≥98.5%) for both years. When the result of MaxEnt’s good performance is put together in a 2014–15 or a 1999–2002 change detection scenario, it corroborates ground reports on massive human abuses that have taken place in Unity state of southern Sudan.     

An optimization algorithm inspired by the States of Matter that improves the balance between exploration and exploitation

The ability of an Evolutionary Algorithm (EA) to find a global optimal solution depends on its capacity to find a good rate between exploitation of found-so-far elements and exploration of the search space. Inspired by natural phenomena, researchers have developed many successful evolutionary algorithms which, at original versions, define operators that mimic the way nature solves complex problems, with no actual consideration of the exploration-exploitation balance. In this paper, a novel nature-inspired algorithm called the States of Matter Search (SMS) is introduced. The SMS algorithm is based on the simulation of the states of matter phenomenon. In SMS, individuals emulate molecules which interact to each other by using evolutionary operations which are based on the physical principles of the thermal-energy motion mechanism. The algorithm is devised by considering each state of matter at one different exploration–exploitation ratio. The evolutionary process is divided into three phases which emulate the three states of matter: gas, liquid and solid. In each state, molecules (individuals) exhibit different movement capacities. Beginning from the gas state (pure exploration), the algorithm modifies the intensities of exploration and exploitation until the solid state (pure exploitation) is reached. As a result, the approach can substantially improve the balance between exploration–exploitation, yet preserving the good search capabilities of an evolutionary approach. To illustrate the proficiency and robustness of the proposed algorithm, it is compared to other well-known evolutionary methods including novel variants that incorporate diversity preservation schemes. The comparison examines several standard benchmark functions which are commonly considered within the EA field. Experimental results show that the proposed method achieves a good performance in comparison to its counterparts as a consequence of its better exploration–exploitation balance.     

Getting to grips with automated prepreg handling

Automated manufacturing of composite parts based on prepreg material is receiving increased interest with the rising use of composite materials for high-performance applications. The two main automation alternatives for prepreg layup, automated tape layup and fiber placement, are not cost-effective for all types of products, and manual labor is common for the manufacturing of complex parts in low manufacturing volumes. Alternatives to the two dominant automation solutions have been pursued, but so far these have had a limited impact in industrial applications. This paper presents four different solutions for automated layup of prepreg plies to flat laminates that can be formed in a subsequent forming process, which decrease the system complexity. The solutions target products where the layup of flat laminates today is done manually due to technical limitations or cost considerations. The layup solutions must manage challenges caused by material properties such as low material rigidity and tack, and be able to handle a high number of ply shapes. All four solutions are designed for prepreg that is covered with a stiff backing paper. The aim of the paper is to analyze and compare the four solutions. It can be concluded that the most versatile solution is a dual-arm robot equipped with simple end effectors. The dual-arm solution presents a possibility to control the pick-up and lay-down motions that make peeling motions possible, which is advantageous when picking material that has tacked to the pickup surface.     

A methodology for user directed search in evolutionary design

A designer should be able to express their intentions with a design tool. This work describes a methodology that enables the architect to directly interact with the encoding of designs they find aesthetically pleasing. Broadening interaction beyond simple evaluation increases the amount of feedback and bias a user can apply to the search. Increased feedback will have the effect of directing the algorithm to more fruitful areas of the search space. We conduct trials on two interfaces for making localised changes to a design in order to evaluate if the user is capable of directing search. In addition, an examination of the locality of changes made by the users provides an insight into how they explore the search space. The results show that a suitably designed interface is capable of directing search and that the participants used different magnitudes of change during directed search.     

The dorsolateral pre‑frontal cortex bi‑polar error‑related potential in a locked‑in patient implanted with a daily use brain–computer interface

While brain computer interfaces (BCIs) offer the potential of allowing those suffering from loss of muscle control to once again fully engage with their environment by bypassing the affected motor system and decoding user intentions directly from brain activity, they are prone to errors. One possible avenue for BCI performance improvement is to detect when the BCI user perceives the BCI to have made an unintended action and thus take corrective actions. Error-related potentials (ErrPs) are neural correlates of error awareness and as such can provide an indication of when a BCI system is not performing according to the user’s intentions. Here, we investigate the brain signals of an implanted BCI user suffering from locked-in syndrome (LIS) due to late-stage ALS that prevents her from being able to speak or move but not from using her BCI at home on a daily basis to communicate, for the presence of error-related signals. We first establish the presence of an ErrP originating from the dorsolateral pre-frontal cortex (dLPFC) in response to errors made during a discrete feedback task that mimics the click-based spelling software she uses to communicate. Then, we show that this ErrP can also be elicited by cursor movement errors in a continuous BCI cursor control task. This work represents a first step toward detecting ErrPs during the daily home use of a communications BCI.