Modelling and control of a 2-DOF planar parallel manipulator for semiconductor packaging systems

A novel direct-drive planar parallel manipulator for high-speed and high-precision semiconductor packaging systems is presented. High precision kinematics design, significant redaction on moving mass and driving power of the actuators over traditional XY motion stages are the benefits of the proposed manipulator. The mathematical model of the manipulator is obtained using the Newton-Enter method and a practical model-based control design approach is employed to design the PID computed-torque controller. Experimental results demonstrate that the proposed planar parallel manipulator has significant improvements on motion performance in terms of positioning accuracy, settling time and stability when compared with traditional XY stages. This shows that the proposed planar parallel manipulator can provide a superior alternative for replacing traditional XY motion stages in high precision low-payload applications. © 2005 IEEE.published_or_final_versio

The long-term outcome of treated high-risk nonmuscle-invasive bladder cancer

This article is available open access through the publisher’s website from the link below. Copyright © 2012 American Cancer Society.BACKGROUND: The treatment of high-risk nonmuscle-invasive bladder cancer (NMIBC) is difficult given its unpredictable natural history and patient comorbidities. Because current case series are mostly limited in size, the authors report the outcomes from a large, single-center series. METHODS: The authors reviewed all patients with primary, high-risk NMIBC at their institution from 1994 to 2010. Outcomes were matched with clinicopathologic data. Patients who had muscle invasion within 6 months or had insufficient follow-up (<6 months) were excluded. Correlations were analyzed using multivariable Cox regression and log-rank analysis (2-sided; P < .05). RESULTS: In total, 712 patients (median age, 73.7 years) were included. Progression to muscle invasion occurred in 110 patients (15.8%; 95% confidence interval [CI], 13%-18.3%) at a median of 17.2 months (interquartile range, 8.9-35.8 months), including 26.5% (95% CI, 22.2%-31.3%) of the 366 patients who had >5 years follow-up. Progression was associated with age (hazard ratio [HR], 1.04; P = .007), dysplastic urothelium (HR, 1.6; P = .003), urothelial cell carcinoma variants (HR, 3.2; P = .001), and recurrence (HR, 18.3; P .6). CONCLUSIONS: Within a program of conservative treatment, progression of high-risk NMIBC was associated with a poor prognosis. Surveillance and bacillus Calmette-Guerin were ineffective in altering the natural history of this disease. The authors concluded that the time has come to rethink the paradigm of management of this disease.GlaxoSmithKline, Yorkshire Cancer Research, Sheffield Hospitals Charitable Trust, Astellas Educational Foundation, and the European Union

Self-administered acupressure for symptom management among Chinese family caregivers with caregiver stress: a randomized, wait-list controlled trial

published_or_final_versio

Viruses as parasites of wild mammals

Zoologia Africana 1(1): 249-25

Non-standard interactions versus non-unitary lepton flavor mixing at a neutrino factory

The impact of heavy mediators on neutrino oscillations is typically described by non-standard four-fermion interactions (NSIs) or non-unitarity (NU). We focus on leptonic dimension-six effective operators which do not produce charged lepton flavor violation. These operators lead to particular correlations among neutrino production, propagation, and detection non-standard effects. We point out that these NSIs and NU phenomenologically lead, in fact, to very similar effects for a neutrino factory, for completely different fundamental reasons. We discuss how the parameters and probabilities are related in this case, and compare the sensitivities. We demonstrate that the NSIs and NU can, in principle, be distinguished for large enough effects at the example of non-standard effects in the $\mu$-$\tau$-sector, which basically corresponds to differentiating between scalars and fermions as heavy mediators as leading order effect. However, we find that a near detector at superbeams could provide very synergistic information, since the correlation between source and matter NSIs is broken for hadronic neutrino production, while NU is a fundamental effect present at any experiment.Comment: 32 pages, 5 figures. Final version published in JHEP. v3: Typo in Eq. (27) correcte

Highly stretchable polymer semiconductor films through the nanoconfinement effect

Soft and conformable wearable electronics require stretchable semiconductors, but existing ones typically sacrifice charge transport mobility to achieve stretchability. We explore a concept based on the nanoconfinement of polymers to substantially improve the stretchability of polymer semiconductors, without affecting charge transport mobility. The increased polymer chain dynamics under nanoconfinement significantly reduces the modulus of the conjugated polymer and largely delays the onset of crack formation under strain. As a result, our fabricated semiconducting film can be stretched up to 100% strain without affecting mobility, retaining values comparable to that of amorphous silicon. The fully stretchable transistors exhibit high biaxial stretchability with minimal change in on current even when poked with a sharp object. We demonstrate a skinlike finger-wearable driver for a light-emitting di

The Westminster Parliament's Formal Sovereignty in Britain and Europe from a Historical Perspective

In the historical backdrop to domestic British debates about Brexit has been tension between two contrasting and competing conceptions of the Westminster Parliament’s sovereignty. In issue has been whether or how parliamentary sovereignty has been subject to constraint, to limitations of form or substance, in strict legal theory or in practical politics. The tension was the product of a doctrinal dichotomy that Albert Venn Dicey introduced in the late-nineteenth century. He introduced it in attempting to juridicalise or juridify the constitution in his foundational and multi-edition textbook The Law of the Constitution. The dichotomy was, on the one hand, of a formal legal conception of Parliament’s sovereignty as limitless in theory and, on the other hand, of a substantive political conception of its sovereignty as limited in actuality. The tension between these legal and political conceptions has been manifest since then in various formal exercises of Parliament’s sovereignty that have impaired its substance. They include parliamentary enactments that conferred self-government in the process of decolonisation, that granted the executive powers to amend parliamentary legislation through “Henry VIII clauses”, and that delegated various governing powers in devolution. The tension has also been manifest in the enactment of the European Communities Act 1972, by which the Westminster Parliament made domestic legal provision for the UK’s original inclusion in the European Communities. The tension was exacerbated by the unqualified assertion of the unconditional supremacy of Community law by the ECJ, both before and after the 1972 enactment. Through judicial minimalism or false economy − failure to acknowledge, explain and address pressing issues at stake − in the response of the highest British court to the ECJ’s assertion of supremacy, problems in the Westminster Parliament’s legal and political sovereignty were left unresolved and vulnerable to serious objection. They contributed to making the UK’s continued membership of the EU precarious and unstable. The doctrinal and constitutional options and implications for the UK are challenging, as are various searching questions for the EU.ReConFor

Long-term carbon sink in Borneo's forests halted by drought and vulnerable to edge effects

Less than half of anthropogenic carbon dioxide emissions remain in the atmosphere. While carbon balance models imply large carbon uptake in tropical forests, direct on-the-ground observations are still lacking in Southeast Asia. Here, using long-term plot monitoring records of up to half a century, we find that intact forests in Borneo gained 0.43 Mg C ha‾¹ per year (95% CI 0.14—0.72, mean period 1988-2010) above-ground live biomass. These results closely match those from African and Amazonian plot networks, suggesting that the world's remaining intact tropical forests are now en masse out-of-equilibrium. Although both pan-tropical and long-term, the sink in remaining intact forests appears vulnerable to climate and land use changes. Across Borneo the 1997-1998 El Niño drought temporarily halted the carbon sink by increasing tree mortality, while fragmentation persistently offset the sink and turned many edge-affected forests into a carbon source to the atmosphere