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101.
This paper presents technical aspects of a robot manipulator developed to facilitate learning by young children who are generally unable to grasp objects or speak. The severity of these physical disabilities also limits assessment of their cognitive and language skills and abilities. The CRS robot manipulator was adapted for use by children who have disabilities. Our emphasis is on the technical control aspects of the development of an interface and communication environment between the child and the robot arm. The system is designed so that each child has user control and control procedures that are individually adapted. Control interfaces include large push buttons, keyboards, laser pointer, and head-controlled switches. Preliminary results have shown that young children who have severe disabilities can use the robotic arm system to complete functional play-related tasks. Developed software allows the child to accomplish a series of multistep tasks by activating one or more single switches. Through a single switch press the child can replay a series of preprogrammed movements that have a development sequence. Children using this system engaged in three-step sequential activities and were highly responsive to the robotic tasks. This was in marked contrast to other interventions using toys and computer games.  相似文献   
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The authors conducted 2 experiments to assess how phonologically related lures are rejected in a false memory paradigm. Some phonological lures were emotional (i.e., taboo) words, and others were not. The authors manipulated the presence of taboo items on the study list and reduced the ability to use controlled rejection strategies by dividing attention and forcing a short response deadline. The results converge on the idea that participants reduce false alarms to emotional lures by setting more stringent recognition criteria for these items based on their expected memorability. Additionally, emotional lures are less familiar than nonemotional lures because emotional lures have affective and semantic features that mismatch studied nonemotional items. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Retinal ganglion cell (RGC) axons in lizards (reptiles) were found to regenerate after optic nerve injury. To determine whether regeneration occurs because the visual pathway has growth-supporting glia cells or whether RGC axons regrow despite the presence of neurite growth-inhibitory components, the substrate properties of lizard optic nerve myelin and of oligodendrocytes were analyzed in vitro, using rat dorsal root ganglion (DRG) neurons. In addition, the response of lizard RGC axons upon contact with rat and reptilian oligodendrocytes or with myelin proteins from the mammalian central nervous system (CNS) was monitored. Lizard optic nerve myelin inhibited extension of rat DRG neurites, and lizard oligodendrocytes elicited DRG growth cone collapse. Both effects were partially reversed by antibody IN-1 against mammalian 35/250 kD neurite growth inhibitors, and IN-1 stained myelinated fiber tracts in the lizard CNS. However, lizard RGC growth cones grew freely across oligodendrocytes from the rat and the reptilian CNS. Mammalian CNS myelin proteins reconstituted into liposomes and added to elongating lizard RGC axons caused at most a transient collapse reaction. Growth cones always recovered within an hour and regrew. Thus, lizard CNS myelin and oligodendrocytes possess nonpermissive substrate properties for DRG neurons--like corresponding structures and cells in the mammalian CNS, including mammalian-like neurite growth inhibitors. Lizard RGC axons, however, appear to be far less sensitive to these inhibitory substrate components and therefore may be able to regenerate through the visual pathway despite the presence of myelin and oligodendrocytes that block growth of DRG neurites.  相似文献   
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VHF propagation on ⩽5300 km polar paths has been documented during the maximum phase of sunspot cycle 19. Mode analysis on these polar paths has shown that auroral-E ionization (AEI) supported some modes. Electron densities and plasma frequencies which could support AEI modes at frequencies up to 46 MHz have also been measured. Long distance VHF propagation from AEI has also been reported by radio amateurs using frequencies in the 2 m band in a “sidescatter mode”. An AEI experiment has been in operation between Wales (Alaska) and Fairbanks (Alaska) where a 75-watt CW transmitter located in Wales transmits the Morse letter “R” every 5 s, and a receiver in Fairbanks detects the 25.5 MHz signal whenever AEI is present near the midpoint of the 960 km path. Another experiment is underway using a GPS total electron content (TEC) receiving station at Fairbanks also using AEI data from the Wales-Fairbanks experiment. From this, the authors examine 58 passes of GPS satellites whose E-layer penetration points lie close to the midpoint of the Wales-Fairbanks path and find that there is a threshold value of TEC above which auroral-E (AE) propagation occurs. They also find that AEI propagation is strongly correlated with large- and medium-scale E-region structures in TEC determined by the GPS measurements. When TEC ionospheric structures are not present near the Wales-Fairbanks path midpoint, no AEI signal is received. The authors tentatively conclude that the occurrence of these specific TEC signatures may be utilized as predictors of AEI forward propagation on paths within and parallel to the auroral oval  相似文献   
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This paper examines the problem of corridor selection in highway design and routing. We present a model which is designed specifically to deal with ordinal information pertaining to the relative desirability of various potential corridors. A technique for combining ordinal rankings into a consensus is given. An approach to the problem of determining criteria weights is suggested.  相似文献   
109.
In this paper we describe a new class of intelligent knowledge-based system (IKBS) which can be used principally for managerial decision making applications. This class of applications often requires a framework for knowledge acquisition which allows the system to use the knowledge of several experts. In addition, since in most business decision making the objective is maximise profits, there is a need for an inference engine which allows optimisation to be carried out. The new class of IKBS which is described in this paper has both these properties, i.e., the ability to use the knowledge of multiple experts in a convenient way and an inference engine which by performing optimisations is able to pick out the profit maximising decisions. As an illustration of these concepts, a system for allocation decision making is described. The system ‘Retail-opt’ allows the user to solve problems like allocation of space in retail outlets, allocation of space in mail order catalogues, pricing policy decisions for discounted airline tickets, etc. In the paper, the basic concepts behind ‘Retail-opt’ are described and an application of ‘Retail-opt’ to the problem of retail space allocation in a Scandinavian Department Store is given. A number of other systems which use these concepts for more complicated competitive decision making situations are also described.  相似文献   
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AIMS: To characterize the population of drug users consulting the Emergency Room (ER) of a university hospital with acute opiate overdose (AOO) and to assess rate of referral to specialized treatment programme. DESIGN: Survey of a 12-month sample of AOO patients. MEASUREMENTS: Medical and psychosocial features of the drug users, details of emergency treatment and referral by a mobile resuscitation team (SMUR) and the ER of our hospital (CHUV-Lausanne, Switzerland). In addition fatal AOO cases were collected by the Institute of Forensic Medicine (IFM) during the same period. FINDINGS: One hundred and eighty-four cases of AOO (134 patients) were treated. The files of the IFM detailed six additional deceased cases. This population of drug users was characterized by an over-representation of men (73%), by young age (27.4 years), by a high rate of multi-drugs use (90%) and by a high rate of multiple previous overdoses (2.6). Average length of stay was 20.1 hours but 41% of cases stayed less than 8 hours. Only one patient was readmitted within an 8-hour period. When discharged, 78% returned home. Unexpectedly, 67% of patients were not referred to any therapeutic programme for drug addiction. CONCLUSION: This study shows the low mortality of AOO when treated but also demonstrates the need to improve psychosocial evaluation and referral of drug addicts admitted with AOO.  相似文献   
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