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991.
OBJECTIVE: Two experiments explored the effects of display dimensionality, conflict geometry, and time pressure on pilot maneuvering preferences for resolving en route conflicts. BACKGROUND: With the presence of a cockpit display of traffic information (CDTI) that provides graphical airspace information, pilots can use a variety of conflict resolution maneuvers in response to how they perceive the conflict. Inconsistent preference findings from previous research on conflict resolution using CDTIs may be attributable to inherent ambiguities in 3-D perspective displays and/or a limited range of conflict geometries. METHODS: Pilots resolved predicted conflicts using CDTIs with three levels of display dimensionality; the first had two 2-D orthogonal views, the second depicted the airspace in two alternating 3-D perspective views, and the third had a pilot-controlled swiveling viewpoint. RESULTS: Pilots demonstrated the same preferences that have been observed in previous research for vertical over lateral maneuvers in low workload and climbs over descents for level-flight conflicts. With increasing workload the two 3-D perspective displays, but not the 2-D displays, resulted in an increased preference for lateral over vertical maneuvers. Increased time pressure resulted in increased vertical maneuvers, an effect again limited to the two 3-D perspective displays. CONCLUSION: Resolution preferences were more affected by workload and time pressure when the 3-D perspective displays were used, as compared with the 2-D displays, although overall preferences were milder than in previous studies. APPLICATION: Investigating maneuver preferences using the strategic flight planning paradigm employed in this study may be the key to better ensure pilot acceptance of computer-generated resolution maneuvers. 相似文献
992.
The registration of computed tomography (CT) and nuclear medicine (NM) images can substantially enhance patient diagnosis as it allows for the fusion of anatomical and functional information, as well as the attenuation correction of NM images. However, irrespective of the method used, registration accuracy depends heavily on the characteristics of the images that are registered and the degree of similarity between them. This poses a challenge for registering CT and NM images as they have very different characteristics and content. To address the particular problem of registering single photon emission computed tomography (SPECT) oncology studies with corresponding CT, we have proposed to perform a dual-isotope study with simultaneous injection of a tumor tracer and a bone imaging agent to obtain a tumor SPECT and a bone SPECT image that are inherently registered. As bone structures are generally visible in both CT and bone SPECT, performing registration of these images will be more easily attainable than registration of CT and tumor SPECT. By subsequently applying the spatial transformation determined from this registration to the tumor SPECT acquired from the same dual-isotope study, the optimal alignment between the CT and tumor SPECT images can be obtained. In this paper, we present the proof-of-concept of the proposed approach, the MI-based algorithm employed, and the techniques used to select the algorithm's parameters. Our objectives are to show the feasibility of CT and bone SPECT registration using this algorithm and to validate quantitatively the results generated using clinical data. 相似文献
993.
To perform automatic, unconscious inference, the human brain must solve the binding problem by correctly grouping properties with objects. Temporal binding models like SHRUTI already suggest much of how this might be done in a connectionist and localist way by using temporal synchrony. We propose a set of alternatives to temporal synchrony mechanisms that instead use short signatures. This serves two functions: it allows us to explore an additional biologically plausible alternative, and it allows us to extend and improve the capabilities of these models. These extensions model the human ability to both perform unification and handle multiple instantiations of logical terms. To verify our model's feasibility, we simulate it with a computer system modeling simple, neuron-like computations. 相似文献
994.
Christine?Bally-ZengerEmail author Lisa?Eckenwiler Verina?Wild 《Ethik in der Medizin》2017,29(2):133-148
Definition of the problem
The German-language media describes a new trend in long-term care: the migration of persons needing such care to nursing homes abroad, especially to Thailand or East Europe. This type of migration is perceived as a controversial practice. Various articles use terms such as “export of the elderly”, “gerontological colonialism” or “inhumane deportation”. These terms indicate that the migration of persons in need of long-term care from so-called high income countries to low and middle income countries might be problematic from an ethical point of view.Arguments
There has hardly been any academic discussion on this phenomenon. On the basis of the media output and a few scientific articles, we establish that we are dealing with an ethically relevant topic. We then systematically identify relevant ethical aspects. These can be assigned to different levels: an individual-, a societal-, and a global-ethics level. On an individual level we discuss questions of autonomy, relations with relatives, the role of culture and traditions for well-being and best practice in long-term care. On the societal level we discuss structural problems in long-term care, and social justice-related questions. On the global level we connect our topic to the ethics discussion on medical tourism, brain drain and global (health) injustice.Conclusion
In this paper we offer the first, systematic list of relevant ethical issues associated with migration of persons in need of long-term care. In order to proceed with a detailed normative analysis more empirical data on the phenomenon are needed.995.
Rahul Shankar Lisa K. Kemp Nicholas A. Smith Jacob A. Cross Beibei Chen Sergei I. Nazarenko Jin Gyu Park Travis L. Thornell John K. Newman Sarah E. Morgan 《应用聚合物科学杂志》2021,138(23):50537
Polyhedral oligomeric silsesquioxane (POSS) nanostructured chemicals, when incorporated at low levels in thermoplastics, provide processability enhancement and viscosity reduction without compromising other bulk physical properties. POSS has been relatively unexplored in high performance polymers, and there is incomplete understanding of the mechanisms by which POSS produces flow improvements. In this study, polyethersulfone (PES) was melt-blended with trisilanolphenyl (TSP)-POSS and dodecaphenyl (DP)-POSS; and rheological, dielectric spectroscopy, and scanning electron microscopy evaluations were conducted to identify structure/property/processing relationships. TSP-POSS yielded greater processability improvements and viscosity reductions than DP-POSS, suppressed low temperature relaxations to a larger extent, and displayed a greater degree of nanoscale dispersion in the polymer matrix. The findings are evaluated in terms of competing theories of POSS viscosity reduction. 相似文献
996.
Marius Andrei Olariu Corneliu Hamciuc Mihai Asandulesa Elena Hamciuc Elena-Luiza Epure Violeta Tsakiris Gabriela Lisa 《Polymer Engineering and Science》2021,61(10):2639-2652
Highly thermostable low-k polymer films with potential applications as dielectric materials in microelectronic industry were synthesized starting from 9,9-bis[4-(3,4-dicarboxyphenoxy)phenyl]fluorene dianhydride and various diamines. A polyetherimide/silica nanocomposite film was obtained using methyltriethoxysilane as precursor of inorganic phase. The chemical structure was confirmed by FTIR and 1H NMR spectroscopy. Water vapor's sorption capacity, thermal stability, glass transition temperature, thermal diffusivity, specific heat, thermal conductivity, and dielectric characteristics of the films were determined. All the films exhibited excellent thermal stability, with an initial decomposition temperature in the range of 500–530°C. They showed low dielectric constant of 1.98–2.86 and low dielectric loss of 0.0037–0.011, at a frequency of 1 Hz and room temperature. The subglass γ- and β-relaxations, primary α-relaxation, and conductivity relaxation processes were discussed according to the chemical structure of the samples. Quantitative structure–property relationship (QSPR) study was conducted, and linear regression models were formulated to describe the causal relationships between different parameters and polyetherimide properties. 相似文献
997.
Noelia Perez Diaz Lisa A. Lione Victoria Hutter Louise S. Mackenzie 《International journal of molecular sciences》2021,22(6)
Peroxisome proliferator activated receptor beta/delta (PPARβ/δ) is a nuclear receptor ubiquitously expressed in cells, whose signaling controls inflammation. There are large discrepancies in understanding the complex role of PPARβ/δ in disease, having both anti- and pro-effects on inflammation. After ligand activation, PPARβ/δ regulates genes by two different mechanisms; induction and transrepression, the effects of which are difficult to differentiate directly. We studied the PPARβ/δ-regulation of lipopolysaccharide (LPS) induced inflammation (indicated by release of nitrite and IL-6) of rat pulmonary artery, using different combinations of agonists (GW0742 or L−165402) and antagonists (GSK3787 or GSK0660). LPS induced release of NO and IL-6 is not significantly reduced by incubation with PPARβ/δ ligands (either agonist or antagonist), however, co-incubation with an agonist and antagonist significantly reduces LPS-induced nitrite production and Nos2 mRNA expression. In contrast, incubation with LPS and PPARβ/δ agonists leads to a significant increase in Pdk−4 and Angptl−4 mRNA expression, which is significantly decreased in the presence of PPARβ/δ antagonists. Docking using computational chemistry methods indicates that PPARβ/δ agonists form polar bonds with His287, His413 and Tyr437, while antagonists are more promiscuous about which amino acids they bind to, although they are very prone to bind Thr252 and Asn307. Dual binding in the PPARβ/δ binding pocket indicates the ligands retain similar binding energies, which suggests that co-incubation with both agonist and antagonist does not prevent the specific binding of each other to the large PPARβ/δ binding pocket. To our knowledge, this is the first time that the possibility of binding two ligands simultaneously into the PPARβ/δ binding pocket has been explored. Agonist binding followed by antagonist simultaneously switches the PPARβ/δ mode of action from induction to transrepression, which is linked with an increase in Nos2 mRNA expression and nitrite production. 相似文献
998.
Nancy A.Feldman 《个人电脑》2005,11(5)
对喜欢网上购物的人来说,在网上寻找最好的价格已经成为某种休闲运动了。只是有一个问题:在线商店经常在不告知我们的情况下更改规则,而我们好像总是处于比分落后的被动地位。你可能曾受到某家电子零售商的不公正待遇,发誓永远不来这里购物了。你取消了现有订单,决定到其它地方试试。不幸的是,你可能仍然撞进同一家公司的商店,只不过它们的名字不一样。这就是Richard B在网上的经历,他回忆从ButterFly Photo(www.butterflyphoto.com)购买一台数码相机的经历,“下了订单一天后,我接到一个电话。电话称他们要验证一下这个订单。”“然后销售… 相似文献
999.
Narratological research is defined in relation to narrative theory and a cultural psychology perspective. Narrative concepts and methodology are explained, including the configural mode of understanding and principles of narrative analysis. Examples of application in psychological and counseling research are presented, with a discussion of issues of validity and voice. Suggestions are made on how narrative studies are to be evaluated. It is concluded that narratological research, with its focus on meanings and the storied nature of human life, can be especially useful in discovery research on identity development and the experience of counseling and life transitions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
Lent Robert W.; Singley Daniel; Sheu Hung-Bin; Gainor Kathy A.; Brenner Bradley R.; Treistman Dana; Ades Lisa 《Canadian Metallurgical Quarterly》2005,52(3):429
Central variables of social cognitive theory were adapted to forge an integrative model of well-being, which was designed to offer greater utility for therapeutic and self-directed change efforts than the dominant personality view of well-being. The authors present 2 studies using versions of the social cognitive model to predict domain-specific and overall life satisfaction. In both studies--one nomothetic, the other idiographic in measurement approach--findings indicated that satisfaction in particular life domains is predicted by domain-specific social cognitive variables (e.g., self-efficacy, perceived goal progress, environmental resources). Domain satisfaction in valued life domains also explained unique variance in overall life satisfaction, even after controlling for trait positive affectivity or extraversion. Implications for theory, research, and counseling aimed at well-being promotion and maintenance are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献