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排序方式: 共有431条查询结果,搜索用时 15 毫秒
1.
Marc-Joseph Antonini Atharva Sahasrabudhe Anthony Tabet Miriam Schwalm Dekel Rosenfeld Indie Garwood Jimin Park Gabriel Loke Tural Khudiyev Mehmet Kanik Nathan Corbin Andres Canales Alan Jasanoff Yoel Fink Polina Anikeeva 《Advanced functional materials》2021,31(43):2104857
Fiber drawing enables scalable fabrication of multifunctional flexible fibers that integrate electrical, optical, and microfluidic modalities to record and modulate neural activity. Constraints on thermomechanical properties of materials, however, have prevented integrated drawing of metal electrodes with low-loss polymer waveguides for concurrent electrical recording and optical neuromodulation. Here, two fabrication approaches are introduced: 1) an iterative thermal drawing with a soft, low melting temperature (Tm) metal indium, and 2) a metal convergence drawing with traditionally non-drawable high Tm metal tungsten. Both approaches deliver multifunctional flexible neural interfaces with low-impedance metallic electrodes and low-loss waveguides, capable of recording optically-evoked and spontaneous neural activity in mice over several weeks. These fibers are coupled with a light-weight mechanical microdrive (1 g) that enables depth-specific interrogation of neural circuits in mice following chronic implantation. Finally, the compatibility of these fibers with magnetic resonance imaging is demonstrated and they are applied to visualize the delivery of chemical payloads through the integrated channels in real time. Together, these advances expand the domains of application of the fiber-based neural probes in neuroscience and neuroengineering. 相似文献
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Historically ignored or “treated,” clients' religious beliefs are being incorporated into psychotherapy because they influence client and therapist thinking and have potential to heal and harm. This paper examines how professional codes of ethics and research on religion-friendly therapeutic interventions and on helpful and harmful religious beliefs and practices provide direction in dealing with religious matters in psychotherapy. Ethical codes emphasize self-determination, beneficence, and nonmaleficence, which lead to different treatment decisions depending on how they are prioritized. The informed consent process and motivational interviewing have potential to ethically reduce harm and maximize benefits from the client's religious beliefs. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
4.
Reshef Tenne Ronit Popovitz-Biro Anton Twersky Yaron Rosenfeld Hacohen 《Israel journal of chemistry》2001,41(1):7-14
Nanoparticles of various layered compounds having a closed cage or nanotubular structure, designated also inorganic fullerene-like (IF) materials, have been reported in the past. In this work IF-CdCl2 nanoparticles were synthesized by two methods. In one technique, a high temperature evaporation and subsequent condensation of dried cadmium chloride powder was used. In the other method, electron beam irradiation of the source powder led to its recrystallization into closed nanoparticles with a nonhollow core. The two methods are shown to produce nanoparticles of different topologies. While mostly spherical nested structures are obtained from the high temperature process, polyhedra with hexagonal or elongated rectangular characters are obtained by the electron beam induced process. The analysis also shows that, while the source (dried) powder is orthorhombic cadmium chloride monohydrate, the crystallized IF cage consists of the anhydrous 3R polytype which is not stable as bulk material in ambient atmosphere. Consistent with previous observations, this study shows that the seamless structure of the IF materials can stabilize phases, which are otherwise unstable in ambient conditions. 相似文献
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Attacks and Defenses for JTAG 总被引:1,自引:0,他引:1
Editor's note:JTAG is a well-known standard mechanism for in-field test. Although it provides high controllability and observability, it also poses great security challenges. This article analyzes various attacks and proposes protection schemes.—Mohammad Tehranipoor, University of Connecticut 相似文献
7.
Hengzhong Zhuang Joseph A. Gardella Jr. Joseph A. Incavo Sergio Rojstaczer Jerold C. Rosenfeld 《The Journal of Adhesion》2013,89(1-3):199-214
Angle-dependent electron spectroscopy for chemical analysis (ESCA) was used to examine the air facing surface (20–100 Å thick) composition of polyimidesiloxanes with different processing variations, and of varying polydimethylsiloxane (PDMS) content and block length (number of PDMS repeat unit varies from 1 to 9). Polyimide was clearly detected (due to the nitrogen content) in the 20–100 Å surface regions. This shows that a small amount of PDMS and short PDMS segment lengths in polyimidesiloxanes give a surface region with both PDMS and polyimide present. The surface composition, particularly that in the ca. 100 Å region, was correlated to the peel strength of polyimidesiloxane melt pressed to a metal substrate. Our results suggest that both PDMS and polyimide are essential components to rendering a needed peel strength. PDMS, having a good diffusive ability, readily reaches the substrate upon being pressed, achieving intimate contact, while imide groups interact with the substrate, presumably through chemical bonding; these two factors act synergistically to result in a high peel strength. In addition, the interaction mechanism and the failure mechanism involved in bonding polyimidesiloxane and metal substrate were also elucidated based on the ESCA results. 相似文献
8.
Abstract: In the last two decades, a wide range of robotic systems for interior construction tasks was being examined (mainly by research and development institutions around the world). A main parameter that differentiates between these systems is their level of autonomy. Reducing the level of autonomy of a given robotic system necessitates increasing auxiliary human work. The efficiency of the system as a whole (i.e., robot/s + operator/s + worker/s) must be examined in order to determine the proper balance between robots and human beings. This article presents the development of a methodology for evaluating a robotized construction task by examining and comparing various ways to share the work between robots and human operators and workers. The methodology is demonstrated by implementing it on two interior finishing tasks—block laying and wall painting. Testing these tasks included full-scale experiments. The detailed analyses of these two applications show the breakeven points of profitable robotic systems, depending on the combination of their own cost, the hourly cost of construction workers, and the expected hourly cost of construction-robot operators in a given labor market. The results lead to a better understanding of possible human-and-robot integration. In particular, this article provides researchers and developers of construction robotics with a systematic approach for evaluation and validation of various ideas prior to investing resources in actual prototypes. 相似文献
9.
Rosenfeld R. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2000,88(8):1270-1278
Statistical language models estimate the distribution of various natural language phenomena for the purpose of speech recognition and other language technologies. Since the first significant model was proposed in 1980, many attempts have been made to improve the state of the art. We review them, point to a few promising directions, and argue for a Bayesian approach to integration of linguistic theories with data 相似文献
10.
Many collaborative multi-robot application domains have limited areas of operation that cause spatial conflicts between robotic teammates. These spatial conflicts can cause the team's productivity to drop with the addition of robots. This phenomenon is impacted by the coordination methods used by the team-members, as different coordination methods yield radically different productivity results. However, selecting the best coordination method to be used by teammates is a formidable task. This paper presents techniques for creating adaptive coordination methods to address this challenge. We first present a combined coordination cost measure, CCC, to quantify the cost of group interactions. Our measure is useful for facilitating comparison between coordination methods, even when multiple cost factors are considered. We consistently find that as CCC values grow, group productivity falls. Using the CCC, we create adaptive coordination techniques that are able to dynamically adjust the efforts spent on coordination to match the number of perceived coordination conflicts in a group. We present two adaptation heuristics that are completely distributed and require no communication between robots. Using these heuristics, robots independently estimate their combined coordination cost (CCC), adjust their coordination methods to minimize it, and increase group productivity. We use simulated robots to perform thousands of experiment trials to demonstrate the efficacy of our approach. We show that using adaptive coordination methods create a statistically significant improvement in productivity over static methods, regardless of the group size. 相似文献