1,564 research outputs found
Phenolic cutter for machining foam insulation
Pre-pregged fiber glass is an efficient abrasive for machining polystyrene and polyurethane foams. It bonds easily to any cutter base made of aluminum, steel, or phenolic, is inexpensive, and is readily available
Microwave remote sensing of snow experiment description and preliminary results
The active and passive microwave responses to snow were investigated at a site near Steamboat Springs, Colorado during the February and March winter months. The microwave equipment was mounted atop truck-mounted booms. Data were acquired at numerous frequencies, polarizations, and angles of incidence for a variety of snow conditions. The experiment description, the characteristics of the microwave and ground truth instruments, and the results of a preliminary analysis of a small portion of the total data volume acquired in Colorado are documented
Synchronization of spin-torque driven nanooscillators for point contacts on a quasi-1D nanowire: Micromagnetic simulations
In this paper we present detailed numerical simulation studies on the
synchronization of two spin-torque nanooscillators (STNO) in the quasi-1D
geometry: magnetization oscillations are induced in a thin NiFe nanostripe by a
spin polarized current injected via square-shaped CoFe nanomagnets on the top
of this stripe. In a sufficiently large out-of-plane field, a propagating
oscillation mode appears in such a system. Due to the absence of the
geometrically caused wave decay in 1D systems, this mode is expected to enable
a long-distance synchronization between STNOs. Indeed, our simulations predict
that synchronization of two STNOs on a nanowire is possible up to the
intercontact distance 3 mkm (for the nanowire width 50 nm). However, we have
also found several qualitatively new features of the synchronization behaviour
for this system, which make the achievement of a stable synchronization in this
geometry to a highly non-trivial task. In particular, there exist a minimal
distance between the nanocontacts, below which a synchronization of STNOs can
not be achieved. Further, when the current value in the first contact is kept
constant, the amplitude of synchronized oscillations depends non-monotonously
on the current value in the second contact. Finally, for one and the same
currents values through the contacts there might exist several synchronized
states (with different frequencies), depending on the initial conditions.Comment: 13 pages with 4 figurews, recently submitted to PR
Adiabatic Domain Wall Motion and Landau-Lifshitz Damping
Recent theory and measurements of the velocity of current-driven domain walls
in magnetic nanowires have re-opened the unresolved question of whether
Landau-Lifshitz damping or Gilbert damping provides the more natural
description of dissipative magnetization dynamics. In this paper, we argue that
(as in the past) experiment cannot distinguish the two, but that
Landau-Lifshitz damping nevertheless provides the most physically sensible
interpretation of the equation of motion. From this perspective, (i) adiabatic
spin-transfer torque dominates the dynamics with small corrections from
non-adiabatic effects; (ii) the damping always decreases the magnetic free
energy, and (iii) microscopic calculations of damping become consistent with
general statistical and thermodynamic considerations
Retrocessos no contexto de terapia linguística de avaliação
O modelo de assimilação é um modelo integrativo que pode ser aplicado a qualquer tipo de setting terapêutico para a descrição do processo de mudança. A Escala de Assimilação de Experiências Problemáticas (EAEP) descreve o processo de assimilação de experiências problemáticas em terapia. Ainda que a EAEP apresente uma sequência ordenada, estudos demonstram que o processo de assimilação não é contínuo; contrariamente, o processo parece seguir um padrão de altos e baixos, com progressos seguidos de retrocessos, particularmente em psicoterapias cognitivas. Neste artigo, apresentamos uma análise dos retrocessos no processo de uma cliente com um bom prognóstico, Maria, em tratamento com terapia linguística de avaliação. A amostra é composta por 105 retrocessos retirados da análise da assimilação de Maria de três problemas principais. As razões para a maioria dos retrocessos podem ser classificadas numa de três categorias: a zona de desenvolvimento próximo, a metáfora de equilíbrio e as linhas múltiplas. Cada uma destas categorias pode ser compreendida como uma consequência da estratégia cognitiva e ainda como parte do processo da terapia cognitiva e não como um desvio ou insucesso. Neste sentido, os retrocessos, enquadrados no modelo de assimilação, reflectem algumas das principais características da terapia cognitiva. No entanto, não podemos excluir a possibilidade dos retrocessos no desenvolvimento poderem indicar uma perspectiva de insucesso e, como tal, os terapeutas devem estar atentos e procurar solucioná-los
Gilbert Damping in Magnetic Multilayers
We study the enhancement of the ferromagnetic relaxation rate in thin films
due to the adjacent normal metal layers. Using linear response theory, we
derive the dissipative torque produced by the s-d exchange interaction at the
ferromagnet-normal metal interface. For a slow precession, the enhancement of
Gilbert damping constant is proportional to the square of the s-d exchange
constant times the zero-frequency limit of the frequency derivative of the
local dynamic spin susceptibility of the normal metal at the interface.
Electron-electron interactions increase the relaxation rate by the Stoner
factor squared. We attribute the large anisotropic enhancements of the
relaxation rate observed recently in multilayers containing palladium to this
mechanism. For free electrons, the present theory compares favorably with
recent spin-pumping result of Tserkovnyak et al. [Phys. Rev. Lett.
\textbf{88},117601 (2002)].Comment: 1 figure, 5page
Ambivalence in emotion-focused therapy for depression: the maintenance of problematically dominant self-narratives
Objective: Ambivalence can be understood as a cyclical movement between an emerging narrative novelty—an Innovative Moment (IM)—and a return to a problematically dominant self-narrative. The return implies that the IM, with its potential for change is devalued right after its emergence. Our goal is to test the hypothesis that the probability of the client expressing such form of ambivalence decreases across treatment in good-outcome cases but not in poor-outcome cases. Method: Return-to-the-Problem Markers (RPMs) signaling moments of devaluation of IMs were coded in passages containing IMs in six clients with major depression treated with emotion-focused therapy: three good-outcome cases and three poor-outcome cases. Results: The percentage of IMs with RPMs decreased across therapy in good-outcome cases, whereas it remained unchanged and high in the poor-outcome cases. Conclusions: These results were consistent with the theoretical suggestion that therapeutic failure may be associated with this form of ambivalence.Obiettivo: L'ambivalenza può essere considerata come un movimento ciclico tra un nuovo elemento narrativo emergente - Innovative Moment (IM) - e il ritorno ad una auto-narrazione problematica dominante. Il ritorno implica che il IM perde il proprio potenziale di favorire un cambiamento nel momento in cui emerge. Il nostro obiettivo è quello di verificare l'ipotesi che la probabilità che il paziente possa esprimere tale forma di ambivalenza diminuisce nel corso di un trattamento che ha un buon esito, ma non nei casi con esito negativo. Metodo: in sei pazienti affetti da depressione maggiore trattati con terapia focalizzata sulle emozioni, sono stati codificati i passaggi contenenti IM utilizzando il Return-to-the-Problem Markers (RPMs) che segnala i passaggi in cui IM vengono svalutati: tre casi con buon esito e tre con esito negativo. Risultati: La percentuale di IM con gli RPM diminuiva nel corso delle terapie dei casi con buon esito, mentre è rimasto invariato ed elevato nei casi con scarso esito. Conclusioni: Questi risultati sono coerenti con il presupposto teorico che il fallimento terapeutico possa essere associato a questa forma di ambivalenza.Objetivo: A ambivalência pode ser entendida como um movimento cíclico entre uma novidade narrativa emergente – um Momento de Inovação (MI) – e um retorno à narrativa problemática dominante. O retorno implica que o MI, com o seu potencial para a mudança, seja desvalorizado logo após a sua emergência. O nosso objetivo é testar a hipótese de que a probabilidade do cliente expressar tal forma de ambivalência diminui ao longo do tratamento em casos de sucesso mas não em casos de insucesso terapêutico. Método: Marcadores de Retorno ao Problema (MRP) que assinalam momentos de desvalorização dos MIs foram codificados em passagens contendo MIs em seis casos de clientes com depressão major tratados com terapia focada nas emoções: três casos de sucesso e três casos de insucesso. Conclusões: Estes resultados foram consistentes com as sugestões teóricas de que o insucesso terapêutico poderá estar associado a esta forma de ambivalência.Ziel: Ambivalenz kann als zyklische Bewegung zwischen einer emergenten narrativen Neuheit – einem Innovative Moment (IM) – und einer Rückkehr zu einer problematischen dominanten Selbst-Erzählung verstanden werden. Diese Rückkehr impliziert, dass der IM mit seinem Potential für Veränderung direkt nach seinem Auftauchen abgewertet wird. Unser Ziel ist die Hypothese zu testen, dass die Wahrscheinlichkeit, dass der Klient eine solche Form der Ambivalenz zeigt, bei Fällen mit gutem Therapieergebnis über die Behandlung abnimmt, aber nicht in Fällen mit schlechtem Ergebnis. Methode: Rückkehr-zu-dem-Problem Marker (RPMs), die Momente signalisieren, in denen IMs abgewertet werden, wurden in Passagen, die IMs beinhalten, von sechs Klienten mit Major Depression, die mit emotionsfokussierter Therapie behandelt wurden, kodiert: 3 Fälle mit gutem und 3 Fälle mit schlechtem Therapieergebnis. Ergebnisse: Der Prozentsatz von IMs mit RPMs verringerte sich bei Fällen mit gutem Ergebnis über die Therapie hinweg, wohingegen er in den Fällen mit schlechtem Ergebnis unverändert und hoch blieb. Schlussfolgerung: Die Ergebnisse waren mit dem theoretischen Vorschlag konsistent, dass therapeutischer Misserfolg mit dieser Form der Ambivalenz assoziiert ist.目標:矛盾可以視為是種擺盪在新產生的新穎敘說—創意時刻(IM)—和回復到一種有問題的支配性自我敘說之間的循環動作。回復意味著潛藏改變契機的IM,其價值在出現後即被摒棄。我們的目標是檢視以下假設的可能性:「在具良好成效的案例中,案主在治療歷程中表達這種形式的矛盾會降低;而在不良成效的案例中則否」。方法:在六位具有嚴重憂鬱症患者的IM段落中,找到顯示IM價值降低時刻的故態復萌標記(RPMs)並加以編碼。這六位患者均接受情緒焦點治療,其中三位為具良好成效案例,另外三位為不良成效案例。結果:在具良好成效案例中,IM當中具有RPM的比率降低;而在不良成效的案例中,RPM的比率維持不變或更高。結論:此結果與理論假設一致,即假設治療的失敗可能與這種形式的矛盾有關
Spin-torque driven magnetization dynamics in a nanocontact setup for low external fields: numerical simulation study
We present numerical simulation studies of the steady-state magnetization
dynamics driven by a spin-polarized current in a point contact geometry for the
case of a relatively large contact diameter (D = 80 nm) and small external
field (H = 30 Oe). We show, that under these conditions the magnetization
dynamics is qualitatively different from the dynamics observed for small
contacts in large external fields. In particular, the 'bullet' mode with a
homogeneous mode core, which was the dominating localized mode for small
contacts, is not found here. Instead, all localized oscillation modes observed
in simulations correspond to different motion kinds of vortex-antivortex (V-AV)
pairs. These kinds include rotational and translational motion of pairs with
the V-AV distance d ~ D and creation/annihilation of much smaller (satellite)
V-AV pairs. We also show that for the geometry studied here the Oersted field
has a qualitative effect on the magnetization dynamics of a 'free' layer. This
effect offers a possibility to control magnetization dynamics by a suitable
electric contact setup, optimized to produce a desired Oersted field. Finally,
we demonstrate that when the magnetization dynamics of the 'fixed' layer
(induced only by the stray field interaction with the 'free' layer) is taken
into account, the threshold current for the oscillation onset is drastically
reduced and new types of localized modes appear. In conclusion, we show that
our simulations reproduce semiquantitatively several important features of the
magnetization dynamics in a point contact system for low external fields
reported experimentally.Comment: 26 pages, 12 figures, submitted to Phys. Rev.
Looking both ways
On the occasion of the 25th anniversary of the journal, Psychotherapy Research, three former editors first look back at: (i) the controversial persistence of the Dodo verdict (i.e., the observation that all bona fide therapies seem equally effective); (ii) the connection between process and outcome; (iii) the move toward methodological pluralism; and (iv) the politicization of the field around evidence-based practice and treatment guidelines. We then look forward to the next 25 years, suggesting that it would be promising to focus on three areas: (i) systematic theory-building research; (ii) renewed attention to fine-grained study of therapist techniques; and (iii) politically expedient research on the outcomes of marginalized or emerging therapies
Challenges to Satellite Sensors of Ocean Winds: Addressing Precipitation Effects
Measurements of global ocean surface winds made by orbiting satellite radars have provided valuable information to the oceanographic and meteorological communities since the launch of the Seasat in 1978, by the National Aeronautics and Space Administration (NASA). When Quick Scatterometer (QuikSCAT) was launched in 1999, it ushered in a new era of dual-polarized, pencil-beam, higher-resolution scatterometers for measuring the global ocean surface winds from space. A constant limitation on the full utilization of scatterometer-derived winds is the presence of isolated rain events, which affect about 7% of the observations. The vector wind sensors, the Ku-band scatterometers [NASA\u27s SeaWinds on the QuikSCAT and Midori-II platforms and Indian Space Research Organisation\u27s (ISRO\u27s) Ocean Satellite (Oceansat)-2], and the current C-band scatterometer [Advanced Wind Scatterometer (ASCAT), on the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT)\u27s Meteorological Operation (MetOp) platform] all experience rain interference, but with different characteristics. Over this past decade, broad-based research studies have sought to better understand the physics of the rain interference problem, to search for methods to bypass the problem (using rain detection, flagging, and avoidance of affected areas), and to develop techniques to improve the quality of the derived wind vectors that are adversely affected by rain. This paper reviews the state of the art in rain flagging and rain correction and describes many of these approaches, methodologies, and summarizes the results
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