Physiological and biochemical changes of different fresh-cut mango cultivars stored at 5 °C

Treatments to inhibit browning, decay and to extend shelf life of ‘Keitt’, ‘Kent’ and ‘Ataulfo’ mango cultivars as a fresh‐cut produce were investigated. Combinations of calcium chloride (CaCl₂), antioxidants [ascorbic acid (AA), citric acid (CA)] and two commercial film coatings resulted in a reduction of browning and deterioration of fresh‐cut mangoes stored at 5 °C, especially for the Ataulfo cultivar. The use of CaCl₂ + AA + CA significantly reduced colour deterioration, loss of firmness and did not affect sensory characteristics of fresh‐cut mango, with a larger effect in the Ataulfo cultivar. In general, these treatments prevented loss of sugar and vitamin C of cubes during storage at 5 °C. Shelf life of this cultivar was 21 days, while that of Keitt and Kent was only 9 and 12 days, respectively. There is a correlation between carotene and vitamin C content of Ataulfo mango and its longer shelf life compared with the other cultivars.     

Authentication gets personal with biometrics

Securing the exchange of intellectual property and providing protection to multimedia contents in distribution systems have enabled the advent of digital rights management (DRM) systems. User authentication, a key component of any DRM system, ensures that only those with specific rights are able to access the digital information. It is here that biometrics play an essential role. It reinforces security at all stages where customer authentication is needed. Biometric recognition, as a means of personal authentication, is an emerging signal processing area focused on increasing security and convenience of use in applications where users need to be securely identified. In this article, we outline the state-of-the-art of several popular biometric modalities and technologies and provide specific applications where biometric recognition may be beneficially incorporated. In addition, the article also discussed integration strategies of biometric authentication technologies into DRM systems that satisfy the needs and requirements of consumers, content providers, and payment brokers, securing delivery channels and contents.     

Microstructural evolution of Alloy 690 during sensitization at 700 °C

A structural characterization of sensitized Alloy 690 has been carried out. Alloy 690 was solution annealed (SA; 1100 °C for 30 min, water quenched, WQ) and sensitized at 700 °C for 5, 12, 24, 36, 48 and 72 h, followed by water quenched. Techniques employed included scanning electron microscope (SEM), transmission electron microscopy (TEM), X-ray diffraction and corrosion weight-loss tests. It was found that the cubic Cr_0.19Fe_0.7Ni_0.11 phase was the main component in all the conditions. In addition, a grain refinement was observed when the aging time was increased; but after 48 h of aging, a discrete, semicontinuous network of Cr₂₃C₆ precipitates was detected by X-ray diffraction, in addition to the NiCrO₄, Ni₉S₈ and (Fe,Ni)₉S₈ phases found by TEM at the grain boundaries, making this alloy more susceptible to intergranular attack (IGA). After 72 h of aging, chromium continues diffusing, “back-filling” the prior depletion profile, recovering the IGA resistance.     

Promoting social network awareness: A social network monitoring system

To increase communication and collaboration opportunities, members of a community must be aware of the social networks that exist within that community. This paper describes a social network monitoring system – the KIWI system – that enables users to register their interactions and visualize their social networks. The system was implemented in a distributed research community and the results have shown that KIWI facilitates collecting information about social interactions. Furthermore, the visualization of the social networks, given as feedback, appeared to have a positive impact on the group, augmenting their social network awareness.     

Modeling NASA swarm-based systems: using agent-oriented software engineering and formal methods

The need to collect new data and perform new science is causing the complexity of NASA missions to continually increase. This complexity needs to be controlled via new technological advancements and balanced with a reduction in mission and operation costs. Planned and hypothesized missions involve self-management, biological-inspiration based on swarms, and autonomous operation as a means of achieving these goals. We consider a tailored software engineering approach to developing such systems based on agent-oriented software engineering and formal methods. We report on advances in modeling, implementing, and testing NASA swarm-based concept missions.     

A framework for building mobile single and multi-robot applications

The complexity of robot software systems calls for the use of a well-conceived architecture together with programming tools to support it. One common feature of robot architectures is the modular decomposition of systems into simpler and largely independent components. These components implement primitive actions and report events about their state. The robot programming framework proposed here includes a tool (RoboGraph) to program and coordinate the activity (tasks) of these middleware modules. Project developers use the same task programming IDE (RoboGraph) on two different levels. The first is to program tasks that must be executed autonomously by one robot and the second is to program tasks that can include several robots and building elements.Tasks are described using a Signal Interpreted Petri Net (SIPN) editor and stored in an xml file. A dispatcher loads these files and executes the different Petri nets as needed. A monitor that shows the state of all the running nets is very useful for debugging and tracing purposes. The whole system has been used in several applications: A tour-guide robot (GuideBot), a multi-robot surveillance project (WatchBot) and a hospital food and laundry transportation system based on mobile robots.     

Speeding up algorithm selection using average ranking and active testing by introducing runtime

Algorithm selection methods can be speeded-up substantially by incorporating multi-objective measures that give preference to algorithms that are both promising and fast to evaluate. In this paper, we introduce such a measure, A3R, and incorporate it into two algorithm selection techniques: average ranking and active testing. Average ranking combines algorithm rankings observed on prior datasets to identify the best algorithms for a new dataset. The aim of the second method is to iteratively select algorithms to be tested on the new dataset, learning from each new evaluation to intelligently select the next best candidate. We show how both methods can be upgraded to incorporate a multi-objective measure A3R that combines accuracy and runtime. It is necessary to establish the correct balance between accuracy and runtime, as otherwise time will be wasted by conducting less informative tests. The correct balance can be set by an appropriate parameter setting within function A3R that trades off accuracy and runtime. Our results demonstrate that the upgraded versions of Average Ranking and Active Testing lead to much better mean interval loss values than their accuracy-based counterparts.     

Field evaluation of agronomic effectiveness of multi-nutrient fertilizer briquettes for upland crop production

Low nutrient recovery in upland crop production systems has prompted studies to improve the current nutrient management practices to increase fertilizer efficiency. Field studies were conducted in two growing seasons (2012 and 2013) under two land management systems (till and no-till) to evaluate agronomic effectiveness of a multi-nutrient fertilizer briquette (fertilizer briquettes) for upland crop production, using corn as test crop. The fertilizer briquettes were produced through a simple physical compaction of ordinary granular fertilizers with a final nutrient composition of 23.9% N, 19.2% P₂O₅, 19.1% K₂O, 0.9% Zn, and 2.5% S. The agronomic efficiency of the fertilizer briquettes were compared with commercial N sources, urea and ammonium sulfate supplied separately with phosphorus (P), potassium (K), zinc (Zn), and sulfur (S; for urea alone). During the wetter (2013) weather conditions, the fertilizer briquette treatment consistently produced the highest yields in both locations. At Ames Plantation, the fertilizer briquette treatment increased grain yields by ~ 16 and ~ 23% over the treatments having ammonium sulfate and urea granular fertilizers, respectively, and, in Jackson, by 16 and 34% respectively. Nutrient recovery efficiency was also greatest with the fertilizer briquettes treatment. However, during the drier weather conditions (2012), the fertilizer briquettes treatment was the least effective among the three treatments in terms of biomass and grain yields, and nutrient recovery efficiency. We conclude, with adequate rainfall conditions, the fertilizer briquettes could be an efficient fertilizer for upland crop production. However, under drier weather conditions where soil moisture is limited, the fertilizer briquettes may not be an ideal fertilizer source for upland crop production.     

Why friendly AIs won’t be that friendly: a friendly reply to Muehlhauser and Bostrom

In “Why We Need Friendly AI”, Luke Muehlhauser and Nick Bostrom propose that for our species to survive the impending rise of superintelligent AIs, we need to ensure that they would be human-friendly. This discussion note offers a more natural but bleaker outlook: that in the end, if these AIs do arise, they won’t be that friendly.

     

Structural Characterization and Electrochemical Performance of Zr1−xTixCr0.7Mo0.3Ni Alloys

JOM - Three specimens were synthesized presenting the following stoichiometry: Zr1?xTixCr0.7Mo0.3Ni (x?=?0.3; 0.5; 0.7). The substitution of zirconium atoms by a lower atomic...