An expert system for XPLE cable deterioration diagnosis and life forecasting

The recent increase in the demand for power in urban areas has caused changes in the way power is supplied. Underground distribution systems have been introduced for convenience in urban areas and to prevent injuries in case of a crisis. As a result, many new types of power cables are being used. One type, XPLE cables (also called CV cables) have been rapidly taking the place of conventional cables such as OF or SL cables since the 1960s because of their relatively easy installation and maintainability. However, distribution cables used under severe environmental conditions deteriorate rapidly (due mainly to water treeing), and some cables experience insulation breakdown. Therefore, many diagnostic methods have been developed, though they have not been very effective. By combining methods, a high reliability can be achieved in comparison to the use of a single method. However, processing the data is difficult for on-site personnel, so many experts are required. But there is a lack of qualified experts, hence we have turned to the development of expert systems.     

Effects of chemical and plasma surface treatments on the O2-annealed Ni/Au contact to p-Gan

The effects of boiling Aqua Regia (AQ), N₂/Cl₂ plasma followed by AQ and O₂ plasma followed by AQ surface treatments prior to Ni/Au (20 nm/20 nm) metallization to p-GaN:Mg (∼ 3 × 10¹⁷ cm^− 3) have been investigated. N₂/Cl₂ plasma was employed in a bid to lower the Ga/N and O/Ga ratios of the GaN surface to improve the contact properties to p-GaN, while O₂ plasma was employed as an alternative to incorporate O into the Ni/Au system. Results show that a low Ga/N ratio does not necessarily correspond to a better contact. The positive effect of O₂ over N₂ anneal is observed only for the AQ-treated sample, although the mechanisms responsible for its positive effect: NiO formation and Ni/Au layer-reversal were observed for all O₂-annealed contacts. We conclude that the effect of O₂ anneal on the Ni/Au contact is dependant on the p-GaN surface prior to metallization.     

Collaborative assignment using belief-desire-intention agent modeling and negotiation with speedup strategies

In this paper, we propose a distributed agent model that applies belief-desire-intention (BDI) reasoning and negotiation for addressing the linear assignment problem (LAP) collaboratively. In resource allocation, LAP is viewed as seeking a concurrent allocation of one different resource for every task to optimize a linear sum objective function. The proposed model provides a basic agent-based foundation needed for efficient resource allocation in a distributed environment. A distributed agent algorithm that has been developed based on the BDI negotiation model is examined both analytically and experimentally. To improve performance in terms of average negotiation speed and solution quality, two initialization heuristics and two different reasoning control strategies are applied, with the latter yielding different variants of the basic algorithm. Extensive simulations suggest that all the heuristic-algorithm combinations can produce a near optimal solution soon enough in some specific sense. The significance and applicability of the research work are also discussed.     

Training of a feedforward multiple-valued neural network by error backpropagation with a multilevel threshold function.

A technique for the training of multiple-valued neural networks based on a backpropagation learning algorithm employing a multilevel threshold function is proposed. The optimum threshold width of the multilevel function and the range of the learning parameter to be chosen for convergence are derived. Trials performed on a benchmark problem demonstrate the convergence of the network within the specified range of parameters.     

Recognizing and measuring self-regulated learning in a mobile learning environment

With the realization that more research is needed to explore external factors (e.g., pedagogy, parental involvement in the context of K-12 learning) and internal factors (e.g., prior knowledge, motivation) underlying student-centered mobile learning, the present study conceptually and empirically explores how the theories and methodologies of self-regulated learning (SRL) can help us analyze and understand the processes of mobile learning. The empirical data collected from two elementary science classes in Singapore indicates that the analytical SRL model of mobile learning proposed in this study can illuminate the relationships between three aspects of mobile learning: students’ self-reports of psychological processes, patterns of online learning behavior in the mobile learning environment (MLE), and learning achievement. Statistical analyses produce three main findings. First, student motivation in this case can account for whether and to what degree the students can actively engage in mobile learning activities metacognitively, motivationally, and behaviorally. Second, the effect of students’ self-reported motivation on their learning achievement is mediated by their behavioral engagement in a pre-designed activity in the MLE. Third, students’ perception of parental autonomy support is not only associated with their motivation in school learning, but also associated with their actual behaviors in self-regulating their learning.     

Biplane computed cerebral angiotomography of moyamoya disease (author's transl)

In this paper, the authors report biplane computed cerebral angiotomographic findings in 5 cases of Moyamoya disease. The specific features of Moyamoya disease on the CT image were as follows: On the axial plane, the linear structures of the anterior half of the circle of Willis and the proximal portion of the middle cerebral arteries disappeared, and instead of these normal structures, irregular, tortuous or patchy high-density areas just like a "caterpillar" were shown in the basal cistern and medial Sylvian fissures. On the modified coronal plane, the supraclinoid internal carotid arteries and the carotid fork could be identified only with a difficulty, and abnormal, "nebular" high-density areas consisting of irregular, tortuous or patchy high-density vascular components became visible in the basal cistern extending to the basal ganglia. A modified coronal plane and intravenous minimum dose bolus injection method seemed to be more useful for the visualization of these specific features on the CT image. Even before carotid angiography, we can suspect Moyamoya disease for finding these specific features on the CT image. Carotid angiography has been the only method of diagnosing Moyamoya disease. Instead of this invasive examination, computed cerebral angiotomography is useful in detecting Moyamoya disease conveniently and non-invasively. Therefore, we may conclude that computed cerebral angiotomography is very useful method for screening and follow up study of Moyamoya disease.     

Supervising passenger land-transport systems

In this paper, we propose a supervisory control approach, based on controlled automata concepts, for the planning for online service-operations control of a new class of passenger land-transport systems ( PLanTSs). A PLanTS belongs to a class of dynamic demand-responsive transportation systems. Rapid advances in information and communication technologies are providing a new infrastructural and communications basis upon which higher levels of automation, flexibility, and integration in the development of such transportation systems can be achieved, but to achieve these necessitates the use of more formal approaches for system planning and design. The supervisory control theory of Ramadge and Wonham offers one such methodology, which presents the design for service-operations control as a formal synthesis of a modular supervisory controller. Importantly, the design solution is guaranteed to satisfy the given behavioral specifications in some optimal fashion, without blocking the completion of certain defined "mandatory" tasks. The supervisory design methodology is presented and illustrated in detail via what, in our opinion, is a simplified but realistic PLanTS model. A structural property of the PLanTS model is used to analytically establish the nonblocking property of the modular supervisory controller designed. All automaton models for the PLanTS and the behavioral specifications considered are provided, together with the automata design of the corresponding modular supervisor.     

Staling of Starch-based Products: A Comparative Study by Firmness and Pulsed NMR Measurements

A study of the staling of corn starch gel, bread, and rice cup-cake showed that measurements by pulsed NMR (based on the increase in signal from the solid phase of a system on ageing) gave very highly significant correlations (P < 0.001) with firmness measurements using the Instron Food Testing Instrument. Experimental data from the two methods were fitted into the Avrami equation. Values for the Avrami exponent (n) and the rate constant (k) obtained by compression were in good agreement with the corresponding values derived from NMR measurements. The pulsed NMR method thus offers a rapid and non-destructive means of monitoring changes at the molecular level which manifest themselves at the macroscopic level as an increase in firmness during ageing of starch gels and starch-based products.     

Cysteine–Cysteine Motif Chemokine Receptor 5 Expression in Letrozole-Induced Polycystic Ovary Syndrome Mice

Polycystic ovary syndrome (PCOS), which affects 5–10% of women of reproductive age, is associated with reproductive and metabolic disorders, such as chronic anovulation, infertility, insulin resistance, and type 2 diabetes. However, the mechanism of PCOS is still unknown. Therefore, this study used a letrozole-exposed mouse model in which mice were orally fed letrozole for 20 weeks to investigate the effects of letrozole on the severity of reproductive and metabolic consequences and the expression of cysteine–cysteine motif chemokine receptor 5 (CCR5) in letrozole-induced PCOS mice. The letrozole-treated mice showed a disrupted estrous cycle and were arrested in the diestrus phase. Letrozole treatment also increased plasma testosterone levels, decreased estradiol levels, and caused multicystic follicle formation. Furthermore, histological analysis of the perigonadal white adipose tissue (pgWAT) showed no significant difference in the size and number of adipocytes between the letrozole-treated mice and the control group. Further, the letrozole-treated mice demonstrated glucose intolerance and insulin resistance during oral glucose and insulin tolerance testing. Additionally, the expression of CCR5 and cysteine-cysteine motif ligand 5 (CCL5) were significantly higher in the pgWAT of the letrozole-treated mice compared with the control group. CCR5 and CCL5 were also significantly correlated with the homeostasis model assessment of insulin resistance (HOMA-IR). Finally, the mechanisms of insulin resistance in PCOS may be caused by an increase in serine phosphorylation and a decrease in Akt phosphorylation.     

A Fully Autonomous Microrobotic Endoscopy System

In this paper, design of an autonomous microrobotic endoscopy system is presented. The proposed microrobotic endoscope is a vision-guided device, developed to facilitate navigation inside a human colon. The design of the entire system is divided into three areas viz. design of a microrobotic carrier, path planning and guidance, and an off-board control system. A microrobotic design based on pneumatic mechanisms to achieve locomotion and steering is explained. General mathematical analysis governing the differential steering of the robotic tip is also described. The path planning of the microrobot is carried out based on the sensory fusion utilising the quantitative parameters from the captured images and the tactile sensors. A real-time image segmentation scheme is described for extracting the lumen from endoscopic images. An off-board control system to control the directional movements of the microrobot is also explained. The proposed endoscopy system was tested with physical models and animal colons and the experimental observations are presented.