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Algorithms based on deep neural networks (DNNs) have attracted increasing attention from the scientific computing community. DNN based algorithms are easy to implement, natural for nonlinear problems, and have shown great potential to overcome the curse of dimensionality. In this work, we utilize the multi-scale DNN-based algorithm (MscaleDNN) proposed by Liu, Cai and Xu (2020) to solve multi-scale elliptic problems with possible nonlinearity, for example, the p-Laplacian problem. We improve the MscaleDNN algorithm by a smooth and localized activation function. Several numerical examples of multi-scale elliptic problems with separable or non-separable scales in low-dimensional and high-dimensional Euclidean spaces are used to demonstrate the effectiveness and accuracy of the MscaleDNN numerical scheme.  相似文献   
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Introduction Recent reviews found problem gamblers are heterogeneous and recommended subtyping gamblers in treatment studies. Objective Review factors (stage of change, preferred gambling activity, co-occurring disorder, and temporal instability of symptoms) for subtyping by evaluating the evidence for their effects on gambling treatment. Methods Literature review, evidence grading. Results Evidence is limited that any of the reviewed factors affects gambling treatment. Substantial evidence from prospective studies and other evidence from cross-sectional studies and the strong placebo response among pathological gamblers support the temporal instability of gambling symptoms. Conclusions Multiple studies are needed to develop the evidence base needed to subtype gamblers in treatment. Changes in the diagnostic criteria of pathological gambling may be necessary, especially to specify the persistence of gambling-related symptoms.  相似文献   
4.
136例阿片类药物依赖者SCL-90的评定结果分析   总被引:3,自引:0,他引:3  
本文应用SCL-90对136例阿片类药物依赖者进行测评,并与正常人进行对照分析。结果显示研究组总分及各因子分与正常组相比差异有显著性。说明毒品滥用人群心理问题严重,突出表现在焦虑、抑郁等几方面,提示戒毒治疗仅进行临床脱毒治疗是远远不够的,还必须重视这一人群的心理问题,并加以矫正,才能提高工作成效  相似文献   
5.
Multi-joint limbs permit a flexible response to unpredictable events   总被引:1,自引:0,他引:1  
The human arm is kinematically redundant, which may allow flexibility in the execution of reaching movements. We have compared reaching movements with and without kinematic redundancy to unpredictable double-step targets. Subjects sat in front of a digitising tablet and were able to view an arc of four targets reflected in the mirror as virtual images in the plane of the tablet. They were instructed to move, from a central starting point, in as straight a line as possible to a target. In one-third of trials, the target light switched to one of its neighbours during the movement. Subjects made 60 movements using shoulder, elbow and wrist and then another 60 movements in which only shoulder and elbow movement were allowed. By restraining the wrist, the limb was made non-redundant. The path length was calculated for each movement. In single-step trials, there was no significant difference between path lengths performed with and without wrist restraint. As expected there was a significant increase in path length during double-step trials. Moreover this increase was significantly greater when the wrist was restrained. The variability across both single- and double-step movements was significantly less while the wrist was restrained. Importantly the performance time of the movements did not alter significantly for single-step, double-step or restrained movements. These results suggest that the nervous system exploits the intrinsic redundancy of the limb when controlling voluntary movements and is therefore more effective at reprogramming movements to double-step targets. Received: 24 March 1997 / Accepted: 7 July 1997  相似文献   
6.
浅谈基因治疗的现状及其面临的困境   总被引:1,自引:0,他引:1  
基因治疗将在未来的疾病治疗中扮演重要的角色,然而这一新颖的技术却面临着诸多问题,本文论述了基因治疗的发展现状及其所面临的技术难题。  相似文献   
7.
单亲大学生心理健康状况及心理问题的教育对策研究   总被引:3,自引:0,他引:3  
目的针对单亲大学生心理健康问题提供有效的教育对策.方法针对大学新生开展16PF调查并发现单亲大学生的心理问题。结果本次测查共测量被试8302人,删除部分无效量表.实际有效数据为7742人,问卷有效率为93.27%.以一般情况问卷中“是否是单亲家庭子女”回答“是”的.作为单亲大学生的认定标准,检出单亲家庭子女555人,占总人数的7.17%,其中男生占40.0%.女生60.0%.17.5%的单亲出现各种心理问题.调查表明.单亲家庭子女与非单亲家庭子女相比,在乐群性和怀疑性两个因子有显着区别。事实上也表现为与正常大学生心理健康状况的显着差异。结论单亲大学生心理问题表现为:自卑心理、怀旧心理、逆反心理、猜疑心理等等。教育对策:加强社会教育系统、学校教育系统、家庭教育对单亲大学生心理的干预与影响,同时.单亲大学生遗要加强心理健康的自我教育.以多元系统帮助他们形成健全人格。  相似文献   
8.
Summary There are some occasions when it is better to use the Laplacian of the scalp voltages (e.g., for topographic displays and dipole source localization) and other occasions when it is better to use the original voltages (e.g., for comparison to non-Laplacian topography maps). This paper presents a simple algorithm for going between these two representations of the data. The inverse Laplacian involves iterative feedback. An Excel spreadsheet implementation of the algorithm is presented.This research was supported by grant AFOSR 89-0238 from the Air Force Office of Sponsored Research.  相似文献   
9.
谈多媒体教学在医学理论课教学中的问题及措施   总被引:28,自引:3,他引:25  
多媒体技术在教育领域的应用,促进了教育教学理念和方式的变革。然而,通过调查,在医学理论课多媒体教学中出现了一些问题,寻找解决问题的出路,是促进多媒体教学不断成熟和完善,提高现代化教学手段质量的最佳途径。  相似文献   
10.
This paper examines the use of videotape simulation as a research method for the exploration of clinical problem-solving, the challenges posed and the strategies employed to overcome the difficulties encountered are discussed. The simulation forms part of a larger comparative study of outcomes of pre-registration nurse education programmes, commissioned by the English National Board for Nursing, Midwifery and Health Visiting.  相似文献   
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