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41.
JI Haring 《Canadian Metallurgical Quarterly》1998,18(5):14-6, 58
42.
Real-time homogenous translucent material editing 总被引:4,自引:0,他引:4
This paper presents a novel method for real-time homogenous translucent material editing under fixed illumination. We consider the complete analytic BSSRDF model proposed by Jensen et al. [ [JMLH01] ], including both multiple scattering and single scattering. Our method allows the user to adjust the analytic parameters of BSSRDF and provides high-quality, real-time rendering feedback. Inspired by recently developed Precomputed Radiance Transfer (PRT) techniques, we approximate both the multiple scattering diffuse reflectance function and the single scattering exponential attenuation function in the analytic model using basis functions, so that re-computing the outgoing radiance at each vertex as parameters change reduces to simple dot products. In addition, using a non-uniform piecewise polynomial basis, we are able to achieve smaller approximation error than using bases adopted in previous PRT-based works, such as spherical harmonics and wavelets. Using hardware acceleration, we demonstrate that our system generates images comparable to [ [JMLH01] ]at real-time frame-rates. 相似文献
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PURPOSE: This study investigated the pathogenesis of tractional retinal detachment associated with proliferative vitreoretinopathy in an experimental model, using immunohistochemical staining. METHODS: To produce tractional retinal detachment in rabbit eyes, homologous cultured fibroblasts obtained from the gluteal muscle fascia were injected intravitreously. Right eyes of 20 rabbits in the study group, and 7 rabbits in the control group were followed for 26 days at weekly intervals with indirect ophthalmoscopy and fundus photographs. RESULTS: During the follow-up period grade III tractional retinal detachment developed in 11 eyes, grade II in six, and grade 1 in three eyes. The spindle-shaped cells contributed predominantly to the development of epiretinal membrane, and a smaller number of round small and large cells. In 10/17 grade II and III eyes, spindle-shaped cells had vimentin, 7/10 had actin, 5/17 had GFAP, 4/17 had S-100 protein immunoreactivity. Round small and large cells expressed S-100 protein, GFAP and actin in 5/17 eyes. Epiretinal membrane appeared to be formed by spindle-shaped fibroblast-like cells and small and large round glia-like cells. Actin positivity of spindle-shaped and round cells was taken as a marker of contractile elements of the cells and their locomotional features. CONCLUSIONS: These features are believed to be involved in contraction of the membrane and retinal detachment. 相似文献
46.
O van der Heijden HC Chiu TC Park H Takahashi VA LiVolsi JI Risinger JC Barrett A Berchuck AC Evans K Behbakht AW Menzin PC Liu I Benjamin MA Morgan SA King SC Rubin J Boyd 《Canadian Metallurgical Quarterly》1998,23(4):243-247
The degree and nature of patient involvement in consultations with health professionals influences problem and needs recognition and management, and public accountability. This paper suggests a framework for understanding the scope for patient involvement in such consultations. Patients are defined as co-producers of formal health services, whose potential for involvement in consultations depends on their personal rights, responsibilities and preferences. Patients' rights in consultations are poorly defined and, in the National Health Service (NHS), not legally enforceable. The responsibilities of patients are also undefined. I suggest that these are not to deny, of their own volition, the rights of others, which in consultations necessitate mutuality of involvement through information-exchange and shared decision-making. Preferences should be met insofar as they do not militate against responsibilities and rights. 相似文献
47.
Depression is one of the most common reasons for using complementary and alternative therapies. The aim of this article is to provide an overview of the evidence available on the treatment of depression with complementary therapies. Systematic literature searches were performed using several databases, reference list searching, and inquiry to colleagues. Data extraction followed a predefined protocol. The amount of rigorous scientific data to support the efficacy of complementary therapies in the treatment of depression is extremely limited. The areas with the most evidence for beneficial effects are exercise, herbal therapy (Hypericum perforatum), and, to a lesser extent, acupuncture and relaxation therapies. There is a need for further research involving randomized controlled trials into the efficacy of complementary and alternative therapies in the treatment of depression. 相似文献
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This article is based on research into patients' perceptions of being in hospital. Time, ordinarily taken for granted, becomes a significant problem for people in hospital. Patients seek control over time that they do not seem to have during their stay in hospital. They try to keep track of time and find ways of passing it, while believing that precious personal time is lost to them. The insight gained into differing perceptions of time and how patients coped with these can be used to reduce some of the tensions and negative aspects of the way time is experienced in hospital. 相似文献
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This paper concerns the stability analysis problem of discrete linear systems with state saturation using a saturation-dependent Lyapunov functional.We introduce a free matrix characterized by the sum of the absolute value of each elements for each row less than 1,which makes the state with saturation constraint reside in a convex polyhedron.A saturation-dependent Lyapunov functional is then designed to obtain a sufficient condition for such systems to be globally asymptotically stable.Based on this stability criterion,the state feedback control law synthesis problem is also studied.The obtained results are formulated in terms of bilinear matrix inequalities that can be solved by the presented iterative linear matrix inequality algorithm.Two numerical examples are used to demonstrate the effectiveness of the proposed method. 相似文献