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1.
This paper demonstrates the ability of a fully connected feed forward neural network (FFNN) using the backpropagation training algorithm to predict the electromyography (EMG) signal from eight muscles of the shoulder for both exercises not used for training and EMG signals from subjects not used for training. The network showed a good predictive ability for subjects not used for training (r(2) between 0.33 and 0.84) and for activities not used for training (r(2) between 0.56 and 0.89). This may have applications for patients, physical therapists and doctors to monitor patient performance by reviewing the level of agreement between the patient EMG and the predicted EMG. Coupled with traditional methods of evaluation, EMG can provide an excellent measure of how well a patient has responded or is responding to treatment. Incorporating robotic technology could facilitate the use of EMG as an input to an intelligent decision making algorithm used to increase or decrease the level of difficulty according to patient performance.  相似文献   

2.
We argue that objective fidelity evaluation of virtual environments, such as flight simulation, should be human-performance-centred and task-specific rather than measure the match between simulation and physical reality. We show how principled experimental paradigms and behavioural models to quantify human performance in simulated environments that have emerged from research in multisensory perception provide a framework for the objective evaluation of the contribution of individual cues to human performance measures of fidelity. We present three examples in a flight simulation environment as a case study: Experiment 1: Detection and categorisation of auditory and kinematic motion cues; Experiment 2: Performance evaluation in a target-tracking task; Experiment 3: Transferrable learning of auditory motion cues. We show how the contribution of individual cues to human performance can be robustly evaluated for each task and that the contribution is highly task dependent. The same auditory cues that can be discriminated and are optimally integrated in experiment 1, do not contribute to target-tracking performance in an in-flight refuelling simulation without training, experiment 2. In experiment 3, however, we demonstrate that the auditory cue leads to significant, transferrable, performance improvements with training. We conclude that objective fidelity evaluation requires a task-specific analysis of the contribution of individual cues.  相似文献   

3.
Simulators are commonly used to train complex tasks. In particular, simulators are applied to train dangerous tasks, to save costs, and to investigate the impact of different factors on task performance. However, in most cases, the transfer of simulator training to the real task has not been investigated. Without a proof for successful skill transfer, simulators might not be helpful at all or even counter-productive for learning the real task. In this paper, the skill transfer of complex technical aspects trained on a scull rowing simulator to sculling on water was investigated. We assume if a simulator provides high fidelity rendering of the interactions with the environment even without augmented feedback, training on such a realistic simulator would allow similar skill gains as training in the real environment. These learned skills were expected to transfer to the real environment. Two groups of four recreational rowers participated. One group trained on water, the other group trained on a simulator. Within two weeks, both groups performed four training sessions with the same licensed rowing trainer. The development in performance was assessed by quantitative biomechanical performance measures and by a qualitative video evaluation of an independent, blinded trainer. In general, both groups could improve their performance on water. The used biomechanical measures seem to allow only a limited insight into the rowers'' development, while the independent trainer could also rate the rowers'' overall impression. The simulator quality and naturalism was confirmed by the participants in a questionnaire. In conclusion, realistic simulator training fostered skill gains to a similar extent as training in the real environment and enabled skill transfer to the real environment. In combination with augmented feedback, simulator training can be further exploited to foster motor learning even to a higher extent, which is subject to future work.  相似文献   

4.
Introspectiveness and adolescent symptom reporting   总被引:2,自引:0,他引:2  
A new measure of introspectiveness--the tendency to devote diffuse attention to thoughts and feelings about the self--was used to investigate adolescent symptom reporting. Introspectiveness was correlated with psychological distress (r = .40) and with physical symptoms (r = .27) in a random sample of college freshmen, and remained the strongest correlate of distress and symptoms when controlling for a variety of other measures. Women, Jews, and certain Hispanic groups were higher on introspectiveness than other students. An unanticipated, but possibly significant, result was that economic discontinuities and discontinuities involving significant others had markedly different relationships with health. Strong associations between perceptions of parental characteristics, adolescent introspectiveness, and health suggested the importance of socialization processes for understanding distress and symptoms. Finally, measures of emotional sensitivity and time spent alone were associated with introspectiveness and symptom reporting. Taken together, these findings suggest the importance of introspectiveness and its correlates for understanding the processes leading to adolescent symptom reporting.  相似文献   

5.
The experimental evaluation of any total knee replacement (TKR) design should include the pre-implantation quantification of its mechanical performance during tests that simulate the common activities of daily living. To date, few dynamic TKR simulation studies have been conducted before implantation. Once in vivo, the accurate and reproducible assessment of TKR design mechanics is exceedingly difficult, with the secondary variables of the patient and the surgical technique hindering research. The current study utilizes a 6-degree-of-freedom force-controlled knee simulator to quantify the effect of TKR design alone on TKR mechanics during a simulated walking cycle. Results show that all eight TKR designs tested elicited statistically different measures of tibial/femoral kinematics, simulated soft tissue loading, and implant geometric restraint loading during an identical simulated gait cycle, and that these differences were a direct result of TKR design alone. Maximum ranges of tibial kinematics over the eight designs tested were from 0.8mm anterior to 6.4mm posterior tibial displacement, and 14.1 degrees internal to 6.0 degrees external tibial rotation during the walking cycle. Soft tissue and implant reaction forces ranged from 106 and 222N anteriorly to 19 and 127N posteriorly, and from 1.6 and 1.8Nm internally to 3.5 and 5.9Nm externally, respectively. These measures provide valuable experimental insight into the effect of TKR design alone on simulated in vivo TKR kinematics, bone interface loading and soft tissue loading. Future studies utilizing this methodology should investigate the effect of experimentally controlled variations in surgical and patient factors on TKR performance during simulated dynamic activity.  相似文献   

6.
The number of physical activity measures and indexes used in the human literature is large and may result in some difficulty for the average investigator to choose the most appropriate measure. Accordingly, this review is intended to provide information on the utility and limitations of the various measures. Its primary focus is the objective assessment of free‐living physical activity in humans based on physiological and biomechanical methods. The physical activity measures have been classified into three categories:
  • 1 . Measures based on energy expenditure or oxygen uptake, such as activity energy expenditure, activity‐related time equivalent, physical activity level, physical activity ratio, metabolic equivalent, and a new index of potential interest, daytime physical activity level.
  • 2 . Measures based on heart rate monitoring, such as net heart rate, physical activity ratio heart rate, physical activity level heart rate, activity‐related time equivalent, and daytime physical activity level heart rate.
  • 3 . Measures based on whole‐body accelerometry (counts/U time).
Quantification of the velocity and duration of displacement in outdoor conditions by satellites using the Differential Global Positioning System may constitute a surrogate for physical activity, because walking is the primary activity of man in free‐living conditions. A general outline of the measures and indexes described above is presented in tabular form, along with their respective definition, usual applications, advantages, and shortcomings. A practical example is given with typical values in obese and non‐obese subjects. The various factors to be considered in the selection of physical activity methods include experimental goals, sample size, budget, cultural and social/environmental factors, physical burden for the subject, and statistical factors, such as accuracy and precision. It is concluded that no single current technique is able to quantify all aspects of physical activity under free‐living conditions, requiring the use of complementary methods. In the future, physical activity sensors, which are of low‐cost, small‐sized, and convenient for subjects, investigators, and clinicians, are needed to reliably monitor, during extended periods in free‐living situations, small changes in movements and grade as well as duration and intensity of typical physical activities.  相似文献   

7.
The objective of this study was to assess the factor structure and clinical correlates of a 61-item version of the Wender Utah Rating Scale (WURS), a self-report retrospective measure of childhood problems, experiences, and behavior used in ADHD assessment. Given the currently mostly widely used form of the WURS was derived via a criterion-keyed approach, the study aimed to use latent variable modeling of the 61-item WURS to potentially identify more and more homogeneous set of items reflecting current conceptualizations of ADHD symptoms. Exploratory structural equation modeling was used to generate factor scores which were then correlated with neuropsychological measures of intelligence and executive attention as well as a broad measure of personality and emotional functioning. Support for a modified five-factor model was found: ADHD, disruptive mood and behavior, negative affectivity, social confidence, and academic problems. The ADHD factor differed somewhat from the traditional 25-item WURS short form largely through weaker associations with several measures of personality and psychopathology. This study identified a factor more aligned with DSM-5 conceptualization of ADHD as well as measures of other types of childhood characteristics and symptoms which may prove useful for both research and clinical practice.  相似文献   

8.
目的:探讨问卷随访对慢性鼻.鼻窦炎、鼻息肉患者鼻内镜术后疗效的评价意义。方法:采用Lurid-Machay的病人症状评分系统及鼻腔鼻窦结局测量20条(sino.nasaloutcometest-20,SNOT.20)中文版,对127例慢性鼻-鼻窦炎、鼻息肉术前、术后3个月、术后6个月患者进行相关问卷测试,并与100名进行健康入职体检者的相关问卷结果进行比较。结果:鼻内镜术后患者的主观症状在术后3个月较术前均明显改善,并在术后6个月时全面改善,差异均有统计学意义(P〈0.05),但部分症状与健康受访者相比仍有差异。结论:问卷随访作为术后鼻部生理功能恢复的评估手段,有助于对术后疗效进行客观的综合评价。  相似文献   

9.
BackgroundAnxiety, obsessive-compulsive, and stress-related disorders frequently co-occur, and patients often present symptoms of several domains. Treatment involves the use of selective serotonin reuptake inhibitors (SSRIs) and serotonin and norepinephrine reuptake inhibitors (SNRIs), but data on comparative efficacy and acceptability are lacking. We aimed to compare the efficacy of SSRIs, SNRIs, and placebo in multiple symptom domains in patients with these diagnoses over the lifespan through a 3-level network meta-analysis.Methods and findingsWe searched for published and unpublished randomized controlled trials that aimed to assess the efficacy of SSRIs or SNRIs in participants (adults and children) with diagnosis of any anxiety, obsessive-compulsive, or stress-related disorder in MEDLINE, PsycINFO, Embase, and Cochrane Library from inception to 23 April 2015, with an update on 11 November 2020. We supplemented electronic database searches with manual searches for published and unpublished randomized controlled trials registered in publicly accessible clinical trial registries and pharmaceutical companies’ databases. No restriction was made regarding comorbidities with any other mental disorder, participants’ age and sex, blinding of participants and researchers, date of publication, or study language. The primary outcome was the aggregate measure of internalizing symptoms of these disorders. Secondary outcomes included specific symptom domains and treatment discontinuation rate. We estimated standardized mean differences (SMDs) with 3-level network meta-analysis with random slopes by study for medication and assessment instrument. Risk of bias appraisal was performed using the Cochrane Collaboration’s risk of bias tool. This study was registered in PROSPERO (CRD42017069090). We analyzed 469 outcome measures from 135 studies (n = 30,245). All medications were more effective than placebo for the aggregate measure of internalizing symptoms (SMD −0.56, 95% CI −0.62 to −0.51, p < 0.001), for all symptom domains, and in patients from all diagnostic categories. We also found significant results when restricting to the most used assessment instrument for each diagnosis; nevertheless, this restriction led to exclusion of 72.71% of outcome measures. Pairwise comparisons revealed only small differences between medications in efficacy and acceptability. Limitations include the moderate heterogeneity found in most outcomes and the moderate risk of bias identified in most of the trials.ConclusionsIn this study, we observed that all SSRIs and SNRIs were effective for multiple symptom domains, and in patients from all included diagnostic categories. We found minimal differences between medications concerning efficacy and acceptability. This three-level network meta-analysis contributes to an ongoing discussion about the true benefit of antidepressants with robust evidence, considering the significantly larger quantity of data and higher statistical power when compared to previous studies. The 3-level approach allowed us to properly assess the efficacy of these medications on internalizing psychopathology, avoiding potential biases related to the exclusion of information due to distinct assessment instruments, and to explore the multilevel structure of transdiagnostic efficacy.

In a meta-analysis of randomized trials, Natan Pereira Gosmann and colleagues study efficacy of SSRIs and SNRIs for symptoms of anxiety, obsessive-compulsive, and stress-related disorders.  相似文献   

10.
A high number of somatic symptoms have been associated with poor health status and increased health care use. Previous studies focused on number of symptoms without considering the specific symptoms. The aim of the study was to investigate 1) the prevalence of 19 somatic symptoms, 2) the associations between the symptoms, and 3) the associations between the somatic symptoms, self-perceived health and limitations due to physical health accounting for the co-occurrence of symptoms. Information on 19 somatic symptoms, self-perceived health and limitations due to physical health was achieved from a population-based questionnaire survey of 36,163 randomly selected adults in the Capital Region of Denmark in 2006/07. Chain graph models were used to transparently identify and describe the associations between symptoms, self-perceived health and limitations due to physical health. In total, 94.9% of the respondents were bothered by one or more of the 19 somatic symptoms. The symptoms were associated in a complex structure. Still, recognisable patterns were identified within organ systems/body parts. When accounting for symptom co-occurrence; dizziness, pain in legs, respiratory distress and tiredness were all strongly directly associated with both of the outcomes (γ>0.30). Chest pain was strongly associated with self-perceived health, and other musculoskeletal symptoms and urinary retention were strongly associated with limitations due to physical health. Other symptoms were either moderate or not statistically associated with the health status outcomes. Opposite, almost all the symptoms were strongly associated with the two outcomes when not accounting for symptom co-occurrence. In conclusion, we found that somatic symptoms were frequent and associated in a complex structure. The associations between symptoms and health status measures differed between the symptoms and depended on the co-occurrence of symptoms. This indicates an importance of considering both the specific symptoms and symptom co-occurrence in further symptom research instead of merely counting symptoms.  相似文献   

11.
We used two measures to compare the effectiveness of 52 conservation criteria in achieving conservation targets for forest types. The first measure was efficiency. Although widely used, efficiency assumes no loss or reduction of biodiversity features before conservation is implemented. This is invalid in many situations. Often, it is more realistic to assume gradual implementation accompanied by incremental, predictable reduction and loss of biodiversity features. We simulated future landscapes resulting from the annual interplay of loss and conservation of forest types. We then based our second measure, retention, on how well criteria scheduled conservation action to prevent targets being compromised. The simulations partly support predictions about the best criteria for scheduling implementation with continuing biodiversity loss. Retention was weakly related or unrelated to efficiency across 52 criteria. Although retention values were sensitive to changes in targets and rates of conservation and forest loss, one criterion consistently produced highest retention values.  相似文献   

12.
Geometric models of vegetation (conceptual spaces) are reviewed. Spaces with samples or species as axes are termed flortistic spaces, as opposed to ecological space with environmental gradients as axes. The terms floristic and ecological relationships are defined as relationships in floristic and ecological spaces, respectively. Compositional turnover is pointed out as the essence of ecological gradients, and arguments in favour of measuring ecological distance in units of compositional turnover are given. The most important criteria for evaluation of ecological distance measures are considered to be linear response to separation along ecological gradients and robustness. Theoretical disadvantages of measures of floristic relationships used as ecological distance measures are discussed. A new measure of ecological distance, separation along a DCA ordination axis, is proposed. This measure and four measures of floristic relationships were tested on four simulated coenoclines (high and low beta diversity, high and low noise) using four weighting functions. The new measure was generally superior, particularly with noisy data. The distance measures generally performed best with intermediate weighting of a percentage cover scale. Application of DCA to calculation of ecological distances in multi-gradient systems is briefly discussed. The potential of DCA for rescaling of ecological gradients is emphasized, and some possible applications of rescaling are suggested.  相似文献   

13.
The treatment of incontinence presents many unique issues for biofeedback therapists that are routine for professionals in fields such as nursing or medicine. Although, all professional practice is guided by ethical standards, the unique circumstances encountered during biofeedback treatments for this disorder warrant the development of specific guidelines. This is true whether insertable or surface EMG devices are used. Therefore, the purpose of this article is to propose a set of ethical guidelines for biofeedback therapists. The intended audience includes professionals such as psychologists, clinical psychophysiologists, and other mental health-care providers who use biofeedback techniques. These are not formally endorsed by any professional organizations (e.g., APA, AAPB) at this time. Ethical considerations include proper medical evaluation, informed consent, patient instruction, disrobing, nonerotic physical contact, patient safety, and patient satisfaction.  相似文献   

14.
Technological progress and adoption are fundamentally interconnected with environmental challenges faced by society. At the product level, researchers often explore the interplay between technological change and the environment by tracking trends in impacts per unit functionality—for example, gasoline consumed per distance traveled by a vehicle. In this article, we explore an alternative measure: “typical product.” A typical product measure accounts for changes in consumers’ demand and use of products as product quality improves—for example, gasoline consumed for a typical driving pattern for a vehicle. We compare and contrast functionality and typical product measures through a case study of electricity use to fabricate Intel desktop microprocessors from 1995 to 2006. The functionality normalization is measured in terms of electricity use per transistor produced. Results show rapid and sustained exponential decrease. The “typical product” measures electricity use per typical desktop microprocessor of a given year (e.g., a Pentium II in 1998, a Pentium IV in 2002). Results show that, despite fluctuations, energy use per typical microprocessor is roughly constant over the 12‐year period. The explanation of this result is that although technological progress dramatically reduces the energy needed per transistor, it also induces demand for more powerful chips, which contain many more transistors. The typical product measure has applications in defining functional units in life cycle assessment, characterizing rebound effects, and measuring energy efficiency trends.  相似文献   

15.
The conveyor system plays a vital role in improving the performance of flexible manufacturing cells (FMCs). The conveyor selection problem involves the evaluation of a set of potential alternatives based on qualitative and quantitative criteria. This paper presents an integrated multi-criteria decision making (MCDM) model of a fuzzy AHP (analytic hierarchy process) and fuzzy ARAS (additive ratio assessment) for conveyor evaluation and selection. In this model, linguistic terms represented as triangular fuzzy numbers are used to quantify experts’ uncertain assessments of alternatives with respect to the criteria. The fuzzy set is then integrated into the AHP to determine the weights of the criteria. Finally, a fuzzy ARAS is used to calculate the weights of the alternatives. To demonstrate the effectiveness of the proposed model, a case study is performed of a practical example, and the results obtained demonstrate practical potential for the implementation of FMCs.  相似文献   

16.
This article presents a non-invasive speech processing method for the assessment and evaluation of voice hoarseness. A technique based on time-scale analysis of the voice signal is used to decompose the signal into a suitable number of high-frequency details and extract the high-frequency bands of the signal. A discriminating measure, which measures the roll-off in power in the high-frequency bands of the signal, with respect to the decomposition index, is developed. The measure reflects the presence and degree of severity of hoarseness in the analyzed voice signals. The discriminating measure is supported by frequency-domain and time-series analyses of the high-frequency bands of normal and hoarse voice signals to provide a visual aid to the clinician or therapist. A database of sustained long vowels of normal and hoarse voices is created and used to assess the presence and degree of severity of hoarseness. The results obtained by the proposed method are compared to results obtained by perturbation analysis.  相似文献   

17.
129 therapists completed a 70-item questionnaire about working with dreams in psychotherapy. Almost all therapists (92%) worked with dreams in psychotherapy at least occasionally. Therapists reported that 15% of clients had brought dreams into therapy during the past year. Therapists engaged more in exploratory than insight- or action-oriented activities when working with dreams. They were more likely to work on dreams with clients who had troubling dreams or who were interested in working on dreams, but were unlikely to work on dreams with schizophrenic or psychotic clients. Those clinicians who were more likely to work with dreams had more training, higher estimated dream recall, more positive attitudes toward dreams, and did more personal dream work than clinicians who were not likely to work with dreams.  相似文献   

18.
We present a simulation environment called SPIKELAB which incorporates a simulator that is able to simulate large networks of spiking neurons using a distributed event driven simulation. Contrary to a time driven simulation, which is usually used to simulate spiking neural networks, our simulation needs less computational resources because of the low average activity of typical networks. The paper addresses the speed up using an event driven versus a time driven simulation and how large networks can be simulated by a distribution of the simulation using already available computing resources. It also presents a solution for the integration of digital or analogue neuromorphic circuits into the simulation process.  相似文献   

19.
The Neuropsych Questionnaire (NPQ) addresses 2 important clinical issues: how to screen patients for a wide range of neuropsychiatric disorders quickly and efficiently, and how to acquire independent verification of a patient's complaints. The NPQ is available over the Internet in adult and pediatric versions. The adult version of the NPQ consists of 207 simple questions about common symptoms of neuropsychiatric disorders. The NPQ scores patient and/or observer responses in terms of 20 symptom clusters: inattention, hyperactivity-impulsivity, learning problems, memory, anxiety, panic, agoraphobia, obsessions and compulsions, social anxiety, depression, mood instability, mania, aggression, psychosis, somatization, fatigue, sleep, suicide, pain, and substance abuse. The NPQ is reliable (patients tested twice, patient-observer pairs, 2 observers) and discriminates patients with different diagnoses. Scores generated by the NPQ correlate reasonably well with commonly used rating scales, and the test is sensitive to the effects of treatment. The NPQ is suitable for initial patient evaluations, and a short form is appropriate for follow-up assessment. The availability of a comprehensive computerized symptom checklist can help to make the day-to-day practice of psychiatry, neurology, and neuropsychology more objective.  相似文献   

20.
Hand evaluation and mouth evaluation were compared for texture of cheese. Panelists (n = 11) identified seven mouth terms and five hand terms and developed definitions and standard procedures for evaluation during the course of training. The terms were used to evaluate texture properties of fourteen different types of natural and processed full fat and reduced fat cheeses. Hand and mouth evaluation were able to discriminate cheese texture (P≦0.05). Principal component analysis of data revealed that hand and mouth evaluation differentiated the cheeses in a similar manner. Correlation analysis, factor analysis, and canonical analysis revealed that mouth and hand terms were highly correlated (P≦0.05). Either hand or mouth evaluation can be used to discriminate cheese texture.  相似文献   

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