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Additional Conditions (additional + condition)
Selected AbstractsA solution method for the linear Chandrasekhar equationMATHEMATICAL METHODS IN THE APPLIED SCIENCES, Issue 15 2006Elias Wegert Abstract The paper is devoted to the linearized H -equation of Chandrasekhar and Ambarzumyan. A Stieltjes-type transform reduces the equation to a boundary value problem for holomorphic functions in the upper half-plane which is solved in closed form. Additional conditions ensure that the solutions , extend holomorphically to the lower half-plane slit along a straight line segment. The solutions of the original problem are then determined from the boundary values of , on this slit. The approach gives necessary and sufficient conditions for Fredholmness and describes all Fredholm parameters in terms of zeros of two functions 1,K and G associated with the kernel and the right-hand side of the equation. Explicit formulas for the complete set of solutions are presented. Die Arbeit ist der linearisierten H -Gleichung von Chandrasekhar und Ambarzumyan gewidmet. Die Gleichung wird mit Hilfe einer modifizierten Stieltjes-Transformation auf ein Randwertproblem für holomorphe Funktionen in der oberen Halbebene zurückgeführt das in geschlossener Form gelöst wird. Unter zusätzlichen Bedingungen können die Lösungen holomorph in die längs einer Strecke aufgeschnittene untere Halbebene fortgesetzt werden. Die Lösungen , des Ausgangsproblems werden dann aus den Randwerten von , längs des Schlitzes bestimmt. Der Zugang liefert notwendige und hinreichende Bedingungen dafür, dass der Operator Fredholmsch ist und charakterisiert alle Fredholmparameter mit Hilfe der Nullstellen zweier Funktionen 1,K und G, die dem Kern und der rechten Seite der Gleichung zugeordnet sind. Es werden explizite Darstellungen für die vollständige Lösungsmenge angegeben. Copyright © 2006 John Wiley & Sons, Ltd. [source] Transporter associated with antigen processing deficiency: an additional condition associated with bronchiectasisINTERNAL MEDICINE JOURNAL, Issue 3 2007J Zimmer No abstract is available for this article. [source] Kalman filtering over unreliable communication networks with bounded Markovian packet dropoutsINTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 16 2009Nan Xiao Abstract We address the peak covariance stability of time-varying Kalman filter with possible packet losses in transmitting measurement outputs to the filter via a packet-based network. The packet losses are assumed to be bounded and driven by a finite-state Markov process. It is shown that if the observability index of the discrete-time linear time-invariant (LTI) system under investigation is one, the Kalman filter is peak covariance stable under no additional condition. For discrete LTI systems with observability index greater than one, a sufficient condition for peak covariance stability is obtained in terms of the system dynamics and the probability transition matrix of the Markov chain. Finally, the validity of these results is demonstrated by numerical simulations. Copyright © 2008 John Wiley & Sons, Ltd. [source] The radial basis functions method for identifying an unknown parameter in a parabolic equation with overspecified dataNUMERICAL METHODS FOR PARTIAL DIFFERENTIAL EQUATIONS, Issue 5 2007Mehdi Dehghan Abstract Parabolic partial differential equations with overspecified data play a crucial role in applied mathematics and engineering, as they appear in various engineering models. In this work, the radial basis functions method is used for finding an unknown parameter p(t) in the inverse linear parabolic partial differential equation ut = uxx + p(t)u + ,, in [0,1] × (0,T], where u is unknown while the initial condition and boundary conditions are given. Also an additional condition ,01k(x)u(x,t)dx = E(t), 0 , t , T, for known functions E(t), k(x), is given as the integral overspecification over the spatial domain. The main approach is using the radial basis functions method. In this technique the exact solution is found without any mesh generation on the domain of the problem. We also discuss on the case that the overspecified condition is in the form ,0s(t)u(x,t)dx = E(t), 0 < t , T, 0 < s(t) < 1, where s and E are known functions. Some illustrative examples are presented to show efficiency of the proposed method. © 2007 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2007 [source] Z+ fading memory and extensions of input,output mapsINTERNATIONAL JOURNAL OF CIRCUIT THEORY AND APPLICATIONS, Issue 4 2001Irwin W. Sandberg Abstract An Erratum for this article has been published in the International Journal of Circuit Theory and Applications 30(4) 2002, 179. Much is known about time-invariant non-linear systems with inputs and outputs defined on Z+ that possess approximately-finite memory. For example, under mild additional conditions, they can be approximated arbitrarily well by the maps of certain interesting simple structures. An important fact that gives meaning to results concerning such systems is that the approximately-finite-memory condition is known to be often met. Here we consider the known proposition that if a causal time-invariant discrete-time input,output map H has fading memory on a set of bounded functions defined on all of the integers Z, then H can be approximated arbitrarily well by a finite Volterra series operator. We show that in a certain sense, involving the existence of extensions of system maps, this result too has wide applicability. Copyright © 2001 John Wiley & Sons, Ltd. [source] The Co-Occurrence of Chronic Diseases and Geriatric Syndromes: The Health and Retirement StudyJOURNAL OF AMERICAN GERIATRICS SOCIETY, Issue 3 2009Pearl G. Lee MD OBJECTIVES: To analyze the co-occurrence, in adults aged 65 and older, of five conditions that are highly prevalent, lead to substantial morbidity, and have evidence-based guidelines for management and well-developed measures of medical care quality. DESIGN: Secondary data analysis of the 2004 wave of the Health and Retirement Study (HRS). SETTING: Nationally representative health interview survey. PARTICIPANTS: Respondents in the 2004 wave of the HRS aged 65 and older. MEASUREMENTS: Self-reported presence of five index conditions (three chronic diseases (coronary artery disease, congestive heart failure, and diabetes mellitus) and two geriatric syndromes (urinary incontinence and injurious falls)) and demographic information (age, sex, race, living situation, net worth, and education). RESULTS: Eleven thousand one hundred thirteen adults, representing 37.1 million Americans aged 65 and older, were interviewed. Forty-five percent were aged 76 and older, 58% were female, 8% were African American, and 4% resided in a nursing home. Respondents with more conditions were older and more likely to be female, single, and residing in a nursing home (all P<.001). Fifty-six percent had at least one of the five index conditions, and 23% had two or more. Of respondents with one condition, 20% to 55% (depending on the index condition) had two or more additional conditions. CONCLUSION: Five common conditions (3 chronic diseases, 2 geriatric syndromes) often co-occur in older adults, suggesting that coordinated management of comorbid conditions, both diseases and geriatric syndromes, is important. Care guidelines and quality indicators, rather than considering one condition at a time, should be developed to address comprehensive and coordinated management of co-occurring diseases and geriatric syndromes. [source] Brief functional analysis and treatment of eye pokingBEHAVIORAL INTERVENTIONS, Issue 4 2002Jennifer E. MacDonald A brief functional analysis suggested that eye poking exhibited by a 5-year-old boy diagnosed with cortical visual impairment was maintained by automatic reinforcement. Levels of eye poking in additional conditions suggested that the behavior might be maintained by visual stimulation. Response blocking through the use of safety goggles effectively reduced eye poking in the analog setting. Data from the natural environment suggest that, during intervention, eye poking was confined to times when response blocking was not in effect. Copyright © 2002 John Wiley & Sons, Ltd. [source] Capital and the Lagos Presidency: Business as Usual?BULLETIN OF LATIN AMERICAN RESEARCH, Issue 3 2002Eduardo Silva Business-state relations in Chile's new democracy had been relatively tension-free for the first two governments of the centre-left Concertación de Partidos por la Democracia. However, during the first two years of the third Concertación administration, under the presidency of Ricardo Lagos, the relationship soured dramatically. At first glance, an ideological shift in the ruling coalition's centre of gravity would seem to explain the change in business-state relations. During the first two governments more conservative factions of the centrist Christian Democratic party had controlled the Concertación. Lagos, on the other hand, represented the left pole of the coalition and his socialist credentials brought the long shadow of the past on his presidency. This, however is an insufficient cause, three additional conditions must also be taken into account. The first one considers changes in the institutional and economic context that eroded the private sector's confidence in the Concertación's commitment to maintain the free-market socioeconomic model imposed under military rule. The second and third conditions are a decline in the electoral fortunes of the Concertación in favour of conservative parties and a shift in power relations among employers' associations towards more confrontational factions. [source] | ||||||||||||||||