Mining Target-Oriented Fuzzy Correlation Rules to Optimize Telecom Service Management

To optimize telecom service management, it is necessary that information about telecom services is highly related to the most popular telecom service. To this end, we propose an algorithm for mining target-oriented fuzzy correlation rules. In this paper, we show that by using the fuzzy statistics analysis and the data mining technology, the target-oriented fuzzy correlation rules can be obtained from a given database. We conduct an experiment by using a sample database from a telecom service provider in Taiwan. Our work can be used to assist the telecom service provider in providing the appropriate services to the customers for better customer relationship management.Comment: 10 pages, 7 table

Mining Target-Oriented Sequential Patterns with Time-Intervals

A target-oriented sequential pattern is a sequential pattern with a concerned itemset in the end of pattern. A time-interval sequential pattern is a sequential pattern with time-intervals between every pair of successive itemsets. In this paper we present an algorithm to discover target-oriented sequential pattern with time-intervals. To this end, the original sequences are reversed so that the last itemsets can be arranged in front of the sequences. The contrasts between reversed sequences and the concerned itemset are then used to exclude the irrelevant sequences. Clustering analysis is used with typical sequential pattern mining algorithm to extract the sequential patterns with time-intervals between successive itemsets. Finally, the discovered time-interval sequential patterns are reversed again to the original order for searching the target patterns.Comment: 11 pages, 9 table

Electrochemical studies of capacitance in cerium oxide thin films and its relationship to anionic and electronic defect densities

Small polaron carrier density in epitaxial, doped CeO_2 thin films under low oxygen partial pressure was determined from electrochemically-measured capacitance after accounting for interfacial effects and shown to agree well with bulk values

Mechanical Flow Restoration in Acute Ischemic Stroke: A Model System of Cerebrovascular Occlusion: A Dissertation

Stroke is the third most common cause of death and a leading cause of disability in the United States. The existing treatments of acute ischemic stroke (AIS) involve pharmaceutical thrombolytic therapy and/or mechanical thrombectomy. The Food and Drug Administration (FDA)-approved recombinant tissue plasminogen activator (tPA) administration for treatment of stroke is efficacious, but has a short treatment time window and is associated with a risk of symptomatic hemorrhage. Other than tPA, the Mechanical Embolus Removal in Cerebral Ischemia (MERCI) retriever system and the Penumbra Aspiration system are both approved by the FDA for retrieval of thromboemboli in AIS patients. However, the previous clinical studies have shown that the recanalization rate of the MERCI system and the clinical outcome of the Penumbra system are not optimal. To identify the variables which could affect the performance of the thrombectomy devices, much effort has been devoted to evaluate thrombectomy devices in model systems, both in vivo and in vitro, of vascular occlusion. The goal of this study is to establish a physiologically realistic, in vitro model system for the preclinical assessment of mechanical thrombectomy devices. In this study, the model system of cerebrovascular occlusion was mainly composed of a human vascular replica, an embolus analogue (EA), and a simulated physiologic mock circulation system. The human vascular replica represents the geometry of the internal carotid artery (ICA)/middle cerebral artery (MCA) that is derived from image data in a population of patients. The features of the vasculature were characterized in terms of average curvature (AC), diameter, and length, and were used to determine the representative model. A batch manufacturing was developed to prepare the silicone replica. The EA is a much neglected component of model systems currently. To address this limitation, extensive mechanical characterization of commonly used EAs was performed. Importantly, the properties of the EAs were compared to specimens extracted from patients. In the preliminary tests of our model system, we selected a bovine EA with stiffness similar to the thrombi retrieved from the atherosclerotic plaques. This EA was used to create an occlusion in the aforesaid replica. The thrombectomy devices tested included the MERCI L5 Retriever, Penumbra system 054, Enterprise stent, and an ultrasound waveguide device. The primary efficacy endpoint was the amount of blood flow restored, and the primary safety endpoint was an analysis of clot fragments generated and their size distribution. A physiologically realistic model system of cerebrovascular occlusion was successfully built and applied for preclinical evaluation of thrombectomy devices. The recanalization rate of the thrombectomy device was related to the ability of the device to capture the EA during the removal of the device and the geometry of the cerebrovasculature. The risk of the embolic shower was influenced by the mechanical properties of the EA and the design of the thrombectomy device

High electrochemical activity of the oxide phase in model ceria–Pt and ceria–Ni composite anodes

Fuel cells, and in particular solid-oxide fuel cells (SOFCs), enable high-efficiency conversion of chemical fuels into useful electrical energy and, as such, are expected to play a major role in a sustainable-energy future. A key step in the fuel-cell energy-conversion process is the electro-oxidation of the fuel at the anode. There has been increasing evidence in recent years that the presence of CeO_2-based oxides (ceria) in the anodes of SOFCs with oxygen-ion-conducting electrolytes significantly lowers the activation overpotential for hydrogen oxidation. Most of these studies, however, employ porous, composite electrode structures with ill-defined geometry and uncontrolled interfacial properties. Accordingly, the means by which electrocatalysis is enhanced has remained unclear. Here we demonstrate unambiguously, through the use of ceria–metal structures with well-defined geometries and interfaces, that the near-equilibrium H_2 oxidation reaction pathway is dominated by electrocatalysis at the oxide/gas interface with minimal contributions from the oxide/metal/gas triple-phase boundaries, even for structures with reaction-site densities approaching those of commercial SOFCs. This insight points towards ceria nanostructuring as a route to enhanced activity, rather than the traditional paradigm of metal-catalyst nanostructuring

Iron-based ferritin nanocore as a contrast agent

Self-assembling protein cages have been exploited as templates for nanoparticle synthesis. The ferritin molecule, a protein cage present in most living systems, stores excess soluble ferrous iron in the form of an insoluble ferric complex within its cavity. Magnetic nanocores formed by loading excess iron within an engineered ferritin from Archaeoglobus fulgidus (AfFtn-AA) were studied as a potential magnetic resonance (MR) imaging contrast agent. The self-assembly characteristics of the AfFtn-AA were investigated using dynamic light scattering technique and size exclusion chromatography. Homogeneous size distribution of the assembled nanoparticles was observed using transmission electron microscopy. The magnetic properties of iron-loaded AfFtn-AA were studied using vibrating sample magnetometry. Images obtained from a 3.0 T whole-body MRI scanner showed significant brightening of T1 images and signal loss of T2 images with increased concentrations of iron-loaded AfFtn-AA. The analysis of the MR image intensities showed extremely high R2 values (5300 mM^(−1) s^(−1)) for the iron-loaded AfFtn-AA confirming its potential as a T2 contrast agent

The experience of zen meditation on patients with generalized anxiety disorder in Taiwan

This study explored the experience of patients with generalized anxiety disorder (GAD) undertaking a six week intervention of a Zen meditation programme in Taiwan. Mix-methods were used including the Revised State and Trait Anxiety Inventory (RSTAI), repeated focus groups, individual interviews, diaries and field notes. Heidegger’s interpretative phenomenology was adopted as a theoretical framework. Two groups of 9 and 12 patients (n=21) participated in the study. Three themes emerged from repeated focus groups: First ‘Expectation of Zen meditation regarding GAD symptoms included sub themes of ‘ambivalence towards meditation’, ‘crave a good sleep’, ‘stop thinking’ and ‘regain memory and concentration’. The second theme, ‘The process of Zen meditation’ included the sub themes of ‘struggling to reach a state of calm’, ‘signs of improvement’ and ‘an individual process’. The last theme, ‘The cultural beliefs regarding Zen meditation in Taiwan’ involved the ‘spiritual influence’ of Zen meditation practice. Four themes emerged from individual interviews. Firstly, ‘Separation’ referred to the issues that participants faced in dealing with the termination of the programme, including ‘concern about other participants’ and ‘examining the relationship between Zen meditation and self’. The second theme ‘Body experience of Zen meditation practice’ incorporated ‘body awareness’ and ‘preparing to practise Zen meditation’. The third theme, ‘States of mind while meditating’ consisted of ‘the state of engagement with real life’, ‘the state of detachment from real life’ and ‘the state of calm’. Lastly, ‘Benefits of Zen meditation practice’ incorporated the categories ‘less pressure with daily life’ and ‘more acceptance of being a GAD patient’. The RSTAI was administrated at baseline and post intervention and also at the two week follow-up of the Zen meditation programme. Neither the Trait Anxiety Score nor the State Anxiety Score showed significant differences between Groups 1 and 2 at baseline. This allowed the RSTAI data from the 2 groups to be merged.The results of 95% confidence interval for differences of both groups showed a significant improvement in the Trait Anxiety Score over time but not the State Anxiety Score. This study contributes to the existing body of knowledge and associated literature regarding Zen meditation and GAD in three ways. Firstly, the findings confirmed that the essential or authentic traditional qualities of meditation should be addressed in meditation study. Secondly, the meaning of Zen meditation for the groups of GAD patients was revealed in the context of Taiwan society. How their lived experience of GAD shaped their understanding of Zen meditation was interpreted. Thirdly, a comprehensive understanding of Zen meditation is reported. The findings (including themes, i.e. diverse Zen meditation processes, body experiences, concepts of obstacles and spiritual influence) add to the current knowledge by providing insight derived from participants’ lived experiences

Modulating metal-oxygen bonding in lithiated metal oxides with point defects

The strength of the metal-oxygen (M-O) bond in oxides principally determines the band structure and the stability of oxygen relative to O2 gas. Accordingly, such bonding is central to energy storage (for determining the redox potential) and electrocatalysis (for determining adsorbate bonding strength at the electrochemical interface). Traditionally, the M-O bond strength is tuned by changing the metal. We have recently discovered another important knob in LiXMO2: metal vacancies and antisite defects. In these materials, which are ubiquitous as positive electrodes in lithium-ion batteries, metal vacancies can form by moving a metal into the Li van der Waals gap. X-ray and neutron scattering measurements confirmed that introducing metal vacancies can substantially contract neighboring M-O bond length, transforming single bonds to double bonds (i.e., terminal metal oxo ligand). In select local configurations, even the peroxo species (O-O)2- can form. These variations of oxygen bonding leads to dramatic variation in the energetics of the bonding and antibonding states as well as the stability of oxygen relative O2 gas. In this talk, I will discuss the connection between local defect configurations and the M-O and O-O bonding in LiXMO2, where M spans 3d, 4d and 5d transition metals