65 resultados para Stable And Unstable Manifolds


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The party political domain of India is replete with a large number of parties representing the tapestry of Indian society. Many of them are based in specific regions and states, built around social and linguistic identities. While this enhanced the representative character of the parties, it also contributed to varied patterns of political competition and unstable governments. The two major national parties – the Congress and the Bharatiya Janata Party – becoming coalitionable heralded an era of coalition governments both at the Centre and states, enabling parties to increase their power and their pay-offs. Parties across the political spectrum have tended to converge on macro-economic policy, but continue to diverge on social policies and larger issues that confront India, such as nation building and secularism. Chronic lack of internal democracy coupled with the rise of political corruption and clientelist practices are matters of serious concern. A broader view of governance, resisting temptations to concentrate power and pursue personal enrichment, would enable parties to deliver policies for a better, more just society.

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In cyber physical system (CPS), computational resources and physical resources are strongly correlated and mutually dependent. Cascading failures occur between coupled networks, cause the system more fragile than single network. Besides widely used metric giant component, we study small cluster (small component) in interdependent networks after cascading failures occur. We first introduce an overview on how small clusters distribute in various single networks. Then we propose a percolation theory based mathematical method to study how small clusters be affected by the interdependence between two coupled networks. We prove that the upper bounds exist for both the fraction and the number of operating small clusters. Without loss of generality, we apply both synthetic network and real network data in simulation to study small clusters under different interdependence models and network topologies. The extensive simulations highlight our findings: except the giant component, considerable proportion of small clusters exists, with the remaining part fragmenting to very tiny pieces or even massive isolated single vertex; no matter how the two networks are tightly coupled, an upper bound exists for the size of small clusters. We also discover that the interdependent small-world networks generally have the highest fractions of operating small clusters. Three attack strategies are compared: Inter Degree Priority Attack, Intra Degree Priority Attack and Random Attack. We observe that the fraction of functioning small clusters keeps stable and is independent from the attack strategies.

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Through the conjunction of tetraphenylethylene and diketopyrrolopyrrole functionalities, a novel four-directional non-fullerene electron acceptor (denoted as 4D) was designed, synthesized and characterized. The new chromophore is highly soluble (for instance >30 mg mL(-1) in o-dichlorobenzene), thermally stable, and exhibits energy levels matching those of the conventional and routinely used donor polymer poly(3-hexyl thiophene). A power conversion efficiency of 3.86% was obtained in solution-processable bulk-heterojunction devices with a very high open circuit voltage of 1.18 V.

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The delay-tolerant networks (DTNs) are emerging research topics that have attracted keen research efforts from both academia and industry. Different from the traditional communication networks, DTNs consider an extreme network condition where a complete end-to-end path between the data source and destination may not exist, and the network is subject to dynamic node connections and unstable topologies. With the above features, DTNs find broad applications in the situations where legacynetworks cannot work effectively, such as data communications in rural areas, where stable communications infrastructure is not available or costly, and crucial areas, e.g., disaster rescue and battlefield communications. To summarize, the DTNs, as an important technology complementary to traditional networkings, can be widely applied to national welfare and the people’s livelihood.

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To improve consumption of omega-3 fatty acids, foods can be enriched with omega-3 rich oils. Microencapsulation of omega-3 oils minimizes oxidative deterioration and allows their use in stable and easy-to-handle form. Microencapsulation of omega-3 fatty acids can be achieved by using a variety of methods, with the two most commonly used commercial processes being complex coacervation and spray dried emulsions. A variety of other methods are in development including spray chilling, extrusion coating and liposome entrapment. The key parameter in any of these processes is the selection of wall material. For spray dried emulsions and complex coacervates protein or polysaccharides are primarily used as shell material, although complex coacervation is currently commercially limited to gelatin. Here we review the need for microencapsulation of omega-3 oils, methods of microencapsulation and analysis, and the selection of shell material components. In particular, we discuss the method of complex coacervation, including its benefits and limitations. This review highlights the need for research on the fundamentals of interfacial and complexation behaviour of various proteins, gums and polyphenols to encapsulate and deliver omega-3 fatty acids, particularly with regard to broadening the range of shell materials that can be used in complex coacervation of omega-3 rich oils.

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Change of tensile properties, electrical conductivity and microwave shielding of electrochemically synthesized polypyrrole films with time are presented. Highly doped films had good electrical stability, retaining high microwave reflectivity throughout the aging period. Lightly doped films were less stable and partially reflective and absorptive of microwaves. FT-IR spectral observations revealed a progressive increase in intensity of an unsaturated conjugated carbonyl peak, which was not observed in the highly doped films, suggesting that the concentration of the dopant had an influence on the mechanism of degradation of conductivity.

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The oncoid-bearing Chuanshan Formation is a regionally extensive carbonate deposit of predominantly Asselian to early Sakmarian (Early Permian) age in South China, occupying an area of some 500,000 km2. Throughout South China, the oncoid-bearing horizons are generally stable and broadly comparable in lithology, fossil content and the morphology of the oncoid grains. Four types of microfacies are recognized from the oncolite succession and overall they suggest a moderate- to high-energy, wave-agitated shallow marine carbonate platform environment. An analysis of the stratigraphic distribution of oncoid grain size, density, thickness and the bedding structures of the oncolite beds and the number of coating laminae indicate the presence of metre-scale cyclothems, suggestive of possible high-frequency cycles of sea-level fluctuation. Compared to carbonate successions above and below that lack oncolites, and in conjunction with evidence from sequence stratigraphic and isotopic geochemical analyses of coeval carbonate deposits in South China and elsewhere, the origin of the Chuanshan oncolites is linked to a drastic drop in global sea-level at the Pennsylvanian–Permian boundary, that can be correlated closely in timing with the zenith of the Late Palaeozoic Gondwanan glaciation. It is further suggested that the eustatic changes apparent from the deposition of the Chuanshan oncolites and similar coeval deposits in lower palaeolatitudes were coupled with, and influenced by, the contemporaneous high-latitude Gondwanan glaciation, the largest and longest known such event in Phanerozoic Earth history.

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Educators interested in social change have been using an analysis of privilege in their gender and anti-racist work for some time. Through working with adult Australians in a community education programme on asylum seekers, the applicability of an analysis of privilege to the exclusionary discourses concerning asylum seekers and refugees became clear. This paper argues that possessing citizenship of a safe, stable and materially comfortable country (globally privileged citizenship) provides similar unearned assets as does Whiteness, maleness and other characteristics of dominant groups. Through an analysis of citizenship we reverse the gaze that sees refugees and asylum seekers as the problem and place it on those of us who occupy the privileged position. Alternative approaches to exclusionary discourses of citizenship, asylum seekers and refugees are canvassed.

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By coating textiles with electrically conductive organic polymers, we are able to produce functional, intelligent fabrics. These fabrics can be utilised in applications such as gas sensors, actuators, electromagnetic shielding, radar absorption, selected frequency filtering in indoor wireless applications, and heating applications where vital parts of the body can be heated without embedding any wiring through the fabric.

Heat generation in fabrics coated with the conductive polymer polypyrrole was investigated. The fabrics were coated by chemical synthesis methods by oxidizing the pyrrole monomer in the presence of the fabric substrate. Ferric chloride was selected as the oxidizing agent and anthraquinone-2-sulfonic acid (AQSA) sodium salt monohydrate as the dopant.

Conductive fabrics were characterized by resistivity measurements, scanning electron microscopy, thermal imaging, current transmission over a period of time and calculations of power density per unit area. Effects of reaction conditions on the electrical properties and heat generated are presented. Polypyrrole coated fabrics were stable and possessed high electrical conductivity. Resistivity values ranged from 100-500 ohms/square depending on the reaction parameters. When subjected to a constant voltage of 24V, the polypyrrole coated polyester-Lycra® fabric doped with AQSA reached a maximum temperature of 42°C and a power density per unit area of 430 W/m2 was achieved.

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A major proportion of the disease burden and deaths for young people in developed nations is attributable to misuse of alcohol and illicit drugs. Patterns of substance use established in adolescence are quite stable and predict chronic patterns of use, mortality, and morbidity later in life. We integrated fi ndings of systematic reviews to summarise evidence for interventions aimed at prevention and reduction of harms related to adolescent substance use. Evidence of efficacy was available for developmental prevention interventions that aim to prevent onset of harmful patterns in settings such as vulnerable families, schools, and communities, and universal strategies to reduce attractiveness of substance use. Regulatory interventions aim to increase perceived costs and reduce availability and accessibility of substances. Increasing price, restricting settings of use, and raising legal purchase age are eff ective in reducing use of alcohol and tobacco and related harms. Screening and brief intervention are efficacious, but efficacy of a range of treatment approaches has not been reliably established. Harm-reduction interventions are effective in young people involved in risky and injecting substance use.

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Objective: To investigate the prevalence and incidence of overweight and obesity, the frequency of overweight resolution and the influence of parental adiposity during middle childhood.

Design: As part of a prospective cohort study, height and weight were measured in 1997 and 2000/2001. Children were classified as non-overweight, overweight or obese based on standard international definitions. Body mass index (BMI) was transformed into age- and gender-specific Z-scores employing the LMS method and 2000 growth chart data of the Centers for Disease Control and Prevention. Parents self-reported height and weight, and were classified as underweight, healthy weight, overweight or obese based on World Health Organization definitions.

Setting: Primary schools in Victoria, Australia.

Subjects: In total, 1438 children aged 5–10 years at baseline.

Results:
The prevalence of overweight and obesity increased between baseline (15.0 and 4.3%, respectively) and follow-up (19.7 and 4.8%, respectively; P < 0.001 for increase in overweight and obesity combined). There were 140 incident cases of overweight (9.7% of the cohort) and 24 of obesity (1.7% of the cohort); only 3.8% of the cohort (19.8% of overweight/obese children) resolved to a healthy weight. The stability of child adiposity as measured by BMI category (84.8% remained in the same category) and BMI Z-score (r = 0.84; mean change = −0.05) was extremely high. Mean change in BMI Z-score decreased with age (linear trend β = 0.03, 95% confidence interval 0.01–0.05). The influence of parental adiposity largely disappeared when children's baseline BMI was adjusted for.

Conclusions: During middle childhood, the incidence of overweight/obesity exceeds the proportion of children resolving to non-overweight. However, for most children adiposity remains stable, and stability appears to increase with age. Prevention strategies targeting children in early childhood are required.


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The need to diversify Fiji's export base has been identified as an important avenue for reducing Fiji's vulnerabilities in international trade. This paper poses the question: Doubling fish exports or garment exports: which would be most beneficial for the Fijian economy? To achieve the goal of this paper, the computable general equilibrium model is used, this being at the forefront of research on 'impact studies'. The main finding is that when garment exports and fish exports are doubled, the benefits to the Fijian economy are greater from garment exports, suggesting that the latter has stronger linkages with the rest of the economy. On the basis of this finding, policymakers should divert resources towards sustaining the garment industry whose future is uncertain due to expiring trade agreements and unstable economic policies.

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The term “post-traumatic stress disorder” (PTSD) is a relatively new diagnostic label, being formally recognized in 1980 in the Diagnostic Statistical Manual for Psychiatric Illness – Third Edition (DSM-III) of the American Psychiatric Association (APA, 1980). Complex Post-Traumatic Stress Disorder (CP) is a more recently discussed, and newly-classified, phenomenon, initially discussed in the early 1990s (Herman, 1992a). Thus, as research into effective treatments for CP is sparse, the treatment of CP is the topic of this study, in which a guideline-based treatment program developed by the researcher for the treatment of CP is implemented and evaluated. Ten individuals participated in this study, undertaking individualized, guideline-based treatment programs spanning a period of six months. In providing background information relevant to this study, an explanation is provided regarding the nature of CP, and the reasons for its consideration as a separate phenomenon to PTSD. The adequacy of the PTSD formulation in enabling effective assessment and treatment of CP is also explored, with endorsement of previous researchers’ conclusions that the CP construct is more useful than the PTSD construct for assessing and treating survivors of long-term and multiple forms of abuse. The PTSD classification is restrictive, and not necessarily appropriate for certain forms of trauma (such as prolonged trauma, or multiple forms of trauma), as such trauma experiences may lead to specific effects that lay outside those formerly associated with PTSD. Such effects include alterations in affect regulation, consciousness, self-perception, interpersonal relationships, and in systems of meaning. Following discussion regarding the PTSD/CP classification, an examination of treatment methods currently used in the treatment of PTSD, and a review of treatment outcome studies, takes place. The adequacy of primary treatment methods in treating CP symptoms is then examined, with the conclusion that a range of treatment methods could potentially be useful in the treatment of CP symptoms. Individuals with a diagnosis of CP may benefit from the adoption of an eclectic approach, drawing on different treatment options for different symptoms, and constantly evaluating client progress and re-evaluating interventions. This review of treatment approaches is followed by details of an initial study undertaken to obtain feedback from individuals who had suffered long-term/multiple trauma and who had received treatment. Participants in this initial study were asked open-ended questions regarding the treatment approach they had experienced, the most useful aspect of the treatment, the least useful aspect, and other strategies/treatment approaches that may have been useful – but which were not used. The feedback obtained from these individuals was used to inform the development of treatment guidelines for use in the main study, as were recommendations made by Chu (1998). The predominant focus of the treatment guidelines was “ego strengthening”, a term coined by Chu (1998) to describe the “initial (sometimes lengthy) period of developing fundamental skills in maintaining supportive relationships, developing self-care strategies, coping with symptomatology, improving functioning, and establishing a positive self identity” (p.75). Using a case study approach, data are then presented relating to each of the ten individuals involved in the treatment program: details of his/her trauma experience(s)and the impact of the trauma (as perceived by each individual); details of each individual’s treatment program (as planned, and as implemented); post-treatment evaluation of the positive and negative aspects of the treatment program (from the therapist’s perspective); and details of the symptoms reported by the individual post-treatment, via psychometric assessment and also during interview. Analysis and discussion of the data relating to the ten participants in the study are the focal point of this study. The evaluation of the effectiveness of each individual’s treatment has been based predominantly on qualitative data, obtained from an analysis of language (discourse analysis) used by participants to describe their symptoms pre- and post-treatment. Both blatant and subtle changes in the language used by participants to describe themselves, their behaviour, and their relationships pre- and post-treatment have provided an insight into the possible changes that occurred as a result of the treatment program. The language used by participants has been a rich source of data, one that has enabled the researcher to obtain information that could not be obtained using psychometric assessment methods. Most of the participants in this study portrayed notable changes in many of the CP symptoms, including being more stable and having improved capacity to explore their early abuse. Although no direct cause-effect relationship between the participants’ treatment program and the improvements described can be established from this study, the participants’ perception that the program assisted them with their symptoms, and reported many aspects of “ego strengthening”, is of major importance. Such self-perception of strength and empowerment is important if an individual is going to be able to deal with past trauma experiences. In fact, abreactive work may have a greater chance of succeeding if those who have experienced long-term or multiple trauma are feeling more empowered, and more stable, as were the participants in this study (post-intervention). In concluding this study, recommendations have been made in regard to the use of guideline-based treatment programs in the responsible treatment of CP. Strengths and limitations of this study have also been highlighted, and recommendations have been made regarding possibilities for future research related to CP treatment. On the whole, this study has supported strongly other research that highlights the importance of focusing on “ego strengthening” in assisting those who have suffered long-term/multiple trauma experiences. Thus, a guideline-based program focusing on assisting sufferers of long-term trauma with some, or all, of the symptoms of CP, is recommended as an important first stage of any treatment of individuals who have experienced long-term/multiple trauma, allowing them to develop the emotional and psychological strength required to deal with past traumatic events. Clinicians who are treating patients whose history depicts long-term or multiple trauma experiences (either from their childhood, or at some stage in their adult life) need, therefore, to be mindful of assessing individuals for symptoms of CP – so that they can treat these symptoms prior to engaging in any work associated directly with the past traumatic experiences.

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Introduction: While using the Transonic Qc[TM] machine to assess access flow in arteriovenous fistulae (AVF), we observed that when compared to antegrade arterial needle insertion, retrograde arterial needle insertion could regularly produce lower access flow measurements. This study sought to explore this phenomenon.

Method: 23 patients entered and 20 finished the study. Patient selection criteria included: functioning AVF and an adequate AVF length for either retrograde or antegrade arterial needle insertion. After ensuring stable and similar blood pressures, 3 flow measurements were taken during the first 2 hours on the same dialysis day of 3 consecutive weeks using antegrade needle insertion then were repeated on 3 further consecutive weeks using retrograde insertion.

Results: Overall, access flows measured with retrograde insertion were significantly lower by a mean difference of 107.15 ml/min (57-484 ml/min) than the flows measured with antegrade needle placement. In 5/20, 3 recorded minimal difference and 2 had a higher access flows during retrograde insertion. No recirculation was observed during either antegrade or retrograde needle insertion. The paired t-test showed that there was significant difference between the antegrade versus retrograde mean measurements (p = 0.005).

Conclusion: Although the sample size is small and the number of measurements limited, we conclude that access flows may be greater with an antegrade arterial orientation compared to flows recorded with a retrograde orientation. The phenomenon behind this conclusion is yet to be investigated. We suggest that when using the Transonic Qc[TM] access measurement device the arterial needle should always be in the same direction for each measurement for each individual patient.

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The problem of visual simultaneous localization and mapping (SLAM) is examined in this paper using ideas and algorithms from robust control and estimation theory. Using a stereo-vision based sensor, a nonlinear measurement model is derived which leads to nonlinear measurements of the landmark coordinates along with optical flow based measurements of the relative robot-landmark velocity. Using a novel analytical measurement transformation, the nonlinear SLAM problem is converted into the linear filter is guaranteed stable and the ALAM state estimation error is bounded within an ellipsoidal set. No similar results are available for the commonly employed extended Kalman filter which is known to exhibit divergent and inconsistency characteristics in practice.