Mobilising the potential towards low-carbon emissions society in Asia

Emission of CO₂, CH₄, and NO _x is among the main sources of greenhouse gases (GHGs) emitted through human activities such as fossil fuels combustion for power, heat and transportation, industrial processes, and land-use change. Low-carbon emission has become synonymous with GHG emission, which is often expressed in t CO₂ eq. as derived from the major GHG. However, CO₂ emission from fossil fuel constitutes just about 2/3 of GHGs. Low-carbon emission has received high publicity in recent years as a major reason for the potential mitigation of climate change. Achieving low GHG emission targets while decoupling the economic growth from high emissions, pollution, and resource use is desirable. This paper reviews the low-carbon emissions initiatives to develop resilient growth strategies to reduce GHG emissions in Asia and beyond. Four major initiatives, including the modelling of GHG emission and mitigation initiative; sustainable energy systems; sustainable waste management; and education and community outreach, are reviewed for mobilising the potential towards low-carbon emissions societies in Asia. Cooperation from major stakeholders, e.g. government, policy makers, financial institutions, private investors, industrial, commercial sector, residential, has been needed towards realising the goal.     

Natural Deduction for Modal Logic of Judgment Aggregation

We can formalize judgments as (consistent sets of) logical formulas. Judgment aggregation deals with judgments of several agents, which need to be aggregated to a collective judgment. There are several logical formalizations of judgment aggregation. This paper focuses on a modal formalization which nicely expresses classical properties of judgment aggregation rules and famous results of social choice theory, like Arrow’s impossibility theorem. A natural deduction system for modal logic of judgment aggregation is presented in this paper. The system is sound and complete. As an example of derivation, a formal proof of Arrow’s impossibility theorem is given.     

Rapid reacquisition of fear to a completely extinguished context is replaced by transient impairment with additional extinction training.

A series of experiments studied reacquisition of fear reactions to a completely extinguished context. Reacquisition was rapid when reconditioning occurred as soon as the fear reactions were completely extinguished, showing that the original conditioning was intact. However, when reconditioning occurred after massive extinction training, fear reactions were depressed but then recovered across a long retention interval. This recovery was due to reconditioning and was similar to that produced by conditioning a massively preexposed context. These results show that massive extinction converts a potentially dangerous context into one that is merely familiar. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

FCloSM,FGenSM: two efficient algorithms for mining frequent closed and generator sequences using the local pruning strategy

Mining frequent sequences in sequential databases are highly valuable for many real-life applications. However, in several cases, especially when databases are huge and when low minimum support thresholds are used, the cardinality of the result set can be enormous. Consequently, algorithms for discovering frequent sequences exhibit poor performance, showing an important increase in execution time, memory consumption and storage space usage. To address this issue, researchers have studied the tasks of mining frequent closed and generator sequences, as they provide several benefits when compared to the set of frequent sequences. One of the most important benefits is that the cardinalities of frequent closed and generator sequences are generally much less than the cardinality of frequent sequences. Hence, humans find it more convenient to analyze the information provided by closed and generator sequences. Moreover, it was shown that frequent closed sequences have the advantage of being lossless, and they thus preserve information about the frequency of all frequent subsequences, while generator sequences can provide higher accuracy for sequence classification tasks since they are the smallest patterns that characterize groups of sequences. Besides, frequent closed sequences can be combined with generators to produce non-redundant sequential rules and recover the complete set of frequent sequences and their frequencies. This paper proposes two novel algorithms named FCloSM and FGenSM to mine frequent closed and generator sequences efficiently. These algorithms are based on new pruning conditions called extended early elimination (3E) and early pruning techniques named EPCLO and EPGEN, designed to identify non-closed and non-generator patterns early. Based on these techniques, two local pruning strategies called LPCLO and LPGEN are proposed to eliminate non-closed and non-generator patterns more efficiently at two successive levels of the prefix search tree without performing subsequence relation checking. These theoretical results, which are the basis of FCloSM and FGenSM, are mathematically proved and are shown to be more general than those presented in previous work. Extensive experiments show that FCloSM and FGenSM are one to two orders of magnitude faster than the state-of-the-art algorithms for discovering frequent closed sequences (CloSpan, BIDE, ClaSP and CM-ClaSP) and for mining frequent generators (FEAT, FSGP and VGEN), and that FCloSM and FGenSM consume much less memory.     

Thermal stability of TiY membrane

Three mol % yttria-doped titania membranes were prepared by the sol-gel method. Their pore and phase structures were determined by N₂ sorption and X-ray diffraction. It was shown that these membranes had superior properties over the undoped membranes in having higher thermal stability. In practice, yttria doping can be developed for high temperature applications.     

Biologically inspired tree‐climbing robot with continuum maneuvering mechanism

Treebot is the first tree‐climbing robot that is capable of climbing from a tree trunk to a branch. The robot employs several design principles adapted from arboreal animals, including claw gripping and inchworm locomotion, with a certain artificial optimization to achieve high maneuverability on irregular‐shaped trees. Treebot is composed of a pair of tree grippers that permits Treebot to attach to a wide variety of trees with a wide range of gripping curvature, and a novel continuum maneuvering structure that provides high maneuverability and adaptability. In the robot actuation, only five actuators are necessary. Although Treebot weighs only 600 gr, it has a payload capability of 1.75 kg, which is nearly three times its own weight. This paper describes the design process and specifically addresses the robot locomotion and optimization of gripping force. Experimental results demonstrate the robot's ability to climb trees with high maneuverability. © 2012 Wiley Periodicals, Inc.     

Application of ICME to Engineer Fatigue-Resistant Ni-Base Superalloys Microstructures

Critical rotating components used in the hot section of gas turbine engines are subject to cyclic loading conditions during operation, and the life of these structures is governed by their ability to resist fatigue. Since it is well known that microstructural parameters, such as grain size, can significantly influence the fatigue behavior of the material, the conventional processes involved with the manufacture of these structures are carefully controlled in an effort to engineer the resulting microstructure. For a commercial Ni-base superalloy, RR1000, the development of process models and deformation mechanism maps has enabled not only control of the resultant grain size but also the ability to tailor and manipulate the resulting grain boundary character distribution. The increased level of microstructural control was coupled with a physics-based fatigue model to form an integrated computational materials engineering framework that was used to guide the design of damage-tolerant microstructures. Simulations from a 3D crystal plasticity finite element model were used to identify microstructural features associated with strain localization during cyclic loading and to guide the design of polycrystalline microstructures optimized for fatigue resistance. Conventionally processed and grain boundary engineered forgings of a commercial Ni-based superalloy, RR1000, were produced to validate the design methodology. For nominally equivalent grain sizes, high-resolution strain maps generated via digital image correlation confirmed that the high density of twin boundaries in the grain boundary engineered material were desirable microstructural features as they contribute to limiting the overall length of persistent slip bands that often serve as precursors for the nucleation of fatigue cracks.     

The effect of long-term ambient aging on the mechanical properties of conducting polysiloxane-polypyrrole graft copolymers

The mechanical behavior of conducting polysiloxane-polypyrrole graft copolymers has been investigated as a function of ambient oxidative aging period. Graft copolymers of N-pyrrolyl-terminated polydimethylsiloxane (SPPy) with pyrrole were synthesized electrochemically at constant potential by using p -toluene sulfonic acid as the supporting electrolyte. Mechanical tests were performed on both unwashed and dichloromethane -washed copolymers after aging. An initial decrease followed by an increase in the tensile strength and strain values was observed with aging. The conductivities and mechanical properties of the films were determined to remain almost unchanged after 6 months of aging at about 46 S/cm.