Finite Controllability of Infinite-Dimensional Quantum Systems

Quantum phenomena of interest in connection with applications to computation and communication almost always involve generating specific transfers between eigenstates, and their linear superpositions. For some quantum systems, such as spin systems, the quantum evolution equation (the Schr\"{o}dinger equation) is finite-dimensional and old results on controllability of systems defined on on Lie groups and quotient spaces provide most of what is needed insofar as controllability of non-dissipative systems is concerned. However, in an infinite-dimensional setting, controlling the evolution of quantum systems often presents difficulties, both conceptual and technical. In this paper we present a systematic approach to a class of such problems for which it is possible to avoid some of the technical issues. In particular, we analyze controllability for infinite-dimensional bilinear systems under assumptions that make controllability possible using trajectories lying in a nested family of pre-defined subspaces. This result, which we call the Finite Controllability Theorem, provides a set of sufficient conditions for controllability in an infinite-dimensional setting. We consider specific physical systems that are of interest for quantum computing, and provide insights into the types of quantum operations (gates) that may be developed.Comment: This is a much improved version of the paper first submitted to the arxiv in 2006 that has been under review since 2005. A shortened version of this paper has been conditionally accepted for publication in IEEE Transactions in Automatic Control (2009

Kadar Hemoglobin Pada Petani Terpapar Pestisida Di Kelurahan Rurukan Kecamatan Tomohon Timur

: Haemoglobin is a red pigment which and it\u27s main function is carries oxygen which located inside the red blood cell. Haemoglobin carries oxygen from lungs to the rest of the body where it releases the oxygen to burn and then carries carbon dioxide back to the lungs to be taken out. Pesticides are toxic substances meant for attracting, seducing, destroying or mitigating any pest. One of the impacts of pesticides on health is blood profile disturbance. The goal of this study is to know the haemoglobin level profile on pesticide-exposed farmers in Rurukan zone, East Tomohon district. This study is a cross sectional study. Twenty six male and twenty four female farmers who have met inclusion criteria were evaluated and fifty samples were analyzed by ABX Pentra XL 80 hematology analyzer to determine the haemoglobin level.Conclusion : The mean haemoglobin level on male respondents were 14,49 g/dL and the mean haemoglobin level on female respondents were 13,28 g/dL. The result of the study suggest that the haemoglobin level on pesticide-exposed farmers in Rurukan zone, East Tomohon district were in normal range

Political ecology and resilience: competing interdisciplinarities?

Both “political ecology” and “resilience” (or socio-ecological systems) are research approaches that explicitly claim to be inter- or even post-disciplinary. Both of these “interdisciplines” are currently dominant in academic study of society-environment interactions, engaging sizeable communities of students and scholars drawn from a range of traditional disciplines. Both approaches seeks to facilitate the kinds of boundary crossings that are crucial at the interface of nature and society, leading to new insights and knowledge, and to solving problems that are not contained within the boundaries. Yet there are inevitably pressures to “discipline” the new “interdisciplines”. In the case of political ecology and resilience, each has separate intellectual traditions, with some fundamental differences in purpose, in epistemology, in explanatory tools, and in ideology – illustrating that there are multiple ways of being interdisciplinary. This chapter explores these differences and reflects on the meaning of interdisciplinarity

The political ecology of weeds : a scalar approach to landscape transformations

How do plants that move and spread across landscapes become branded as weeds and thereby objects of contention and control? We outline a political ecology approach that builds on a Lefebvrian understanding of the production of space, identifying three scalar moments that make plants into 'weeds' in different spatial contexts and landscapes. The three moments are: the operational scale, which relates to empirical phenomena in nature and society; the observational scale, which defines formal concepts of these phenomena and their implicit or explicit 'biopower' across institutional and spatial categories; and the interpretive scale, which is communicated through stories and actions expressing human feelings or concerns regarding the phenomena and processes of socio-spatial change. Together, these three scalar moments interact to produce a political ecology of landscape transformation, where biophysical and socio-cultural processes of daily life encounter formal categories and modes of control as well as emotive and normative expectations in shaping landscapes. Using three exemplar 'weeds' - acacia, lantana and ambrosia - our political ecology approach to landscape transformations shows that weeds do not act alone and that invasives are not inherently bad organisms. Humans and weeds go together; plants take advantage of spaces and opportunities that we create. Human desires for preserving certain social values in landscapes in contradiction to actual transformations is often at the heart of definitions of and conflicts over weeds or invasives

Photodetachment in combined static and dynamic electric fields

Through an exact solution of the time-dependent Schrödinger equation for an electron in a static electric field plus the time-dependent electric field of the detaching radiation, the photodetachment cross section of [Formula Presented] is calculated. Careful attention is paid to ensuring proper limiting behavior as the frequency of the time-dependent field goes to zero. We do not find observable effects of a cross term between the two fields on the detachment cross section. Our results point to possible gauge dependence and other difficulties of S-matrix formulations of multiphoton detachment and ionization. © 2000 The American Physical Society

The Hybrid Approach to Intervention of Chronic Total Occlusions

The "hybrid" approach to chronic total occlusion (CTO) percutaneous coronary intervention (PCI) was developed to provide guidance on optimal crossing strategy selection. Dual angiography remains the cornerstone of clinical decision making in CTO PCI. Four angiographic parameters are assessed: (a) morphology of the proximal cap (clear-cut or ambiguous); (b) occlusion length; (c) distal vessel size and presence of bifurcations beyond the distal cap; and (d) location and suitability of location and suitability of a retrograde conduit (collateral channels or bypass grafts) for retrograde access. Antegrade wire escalation is favored for short (<20 mm) occlusions, usually escalating rapidly from a soft tapered-tip polymer-jacketed guidewire to a stiff polymer-jacketed or tapered-tip guidewire. Antegrade dissection/re-entry is favored in long (≥20 mm long) occlusions, trying to minimize the dissection length by re-entering into the distal true lumen immediately after the occlusion. Primary retrograde approach is preferred for lesions with an ambiguous proximal cap, poor distal target, good interventional collaterals, and heavy calcification,as well as chronic kidney disease. The "hybrid" approach advocates early change between strategies to enable CTO crossing in the most efficacious, efficient, and safe way. Several early studies are demonstrating high success and low complication rates with use of the "hybrid" approach, supporting its expanding use in CTO PCI