• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.12 no.1
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• pp.195-200
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• 2012

We present a new algorithm which can improve the tracking performance of the double-talk robust algorithm. A detection method of the echo path change and a modification method for the update equation of the conventional adaptive filter are proposed. A duration of the high error signal to scale parameter ratio varies according to the call status and this property is used to detect the echo path change. The proposed update equation of the adaptive filter improves the tracking performance by prohibiting wrong selection of the error signal. Simulations using real speech signals and echo paths of the ITU-T G.168 standard confirmed that as compared to the conventional algorithm, the proposed algorithm improved the tracking performance by more than 4 dB.

• Speech Sciences
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• v.7 no.4
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• pp.49-57
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• 2000

This paper proposes an effective decision method focused on evaluating the 'stress position'. Conventional methods usually extract the acoustic parameters and compare them to references in absolute scale, adversely producing unstable results as testing conditions change. To cope with environmental dependency, the proposed method is designed to be model-based and determines the stressed interval by making relative comparison over candidates. The stressed/unstressed models are then induced from normal phone models by adaptive training. The experimental results indicate that the proposed method is promising, and that it is useful for automatic detection of stress positions. The results also show that generating the stressed/unstressed model by adaptive training is effective.

• Journal of Korean Physical Therapy Science
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• v.8 no.2
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• pp.977-987
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• 2001

The purpose of this study was to examine the effects of sensory integration therapy (SIT) on sensory' motor development and adaptive behavior of cerebral palsy children. The design of this study was quasi experiments with a non-equivalent pre- and post-test control design. Subjects of the study were arbitrarily chosen based on predetermined selection criteria among the cerebral palsy children who were treated as out-patients at two rehabilitation hospitals one in Seoul, and the other in Kyunggi-do. The study was conducted between early April and late July in 2000. Fifteen children were in the experimental group and eleven in the control group. The allocation was done based on ease of experimental treatment. A five-step SIT program was devised from a combination of SIT programs suggested by Ayres(1985) and Finks(1989), and an author-designed SIT program for cerebral palsy children. The experimental group was subjected to 20 to 30 minutes of SIT per session. two sessions a week for ten -week period. The effects of SIT were measured with respect to 9 sub-areas that can be administered to cerebral palsy children out of a total of 17 sub-areas in the Southern California Sensory Integration Test (SCSIT) developed by Ayres (1980). In addition. the scale developed by Russell (1993) for Gross Motor Function Measure (GMFM). and Perception Motor Development Test developed by 中司利一 et al.(1987) were also applied. Adaptive behavior was analyzed using guidelines in two unpublished documents - School-Age Checklist for Occupational Therapy by the Wakefield Occupational Therapy Associates, and the OTA-Watertown Clinical Assessment by the Watertown Occupational Therapy Associates-, and an author-developed Adaptive Behavior Checklist. Collected data were statistically analyzed by SPSS PC for chi square test, Mann-Whitney test, Wilcoxon signed rank test, and paired t-test. The results were as follows: 1. In sensory development, the experimental group exhibited a score increase compared to the control group, but the difference was not statistically significant, Although the experimental group showed improvements in all. 9 sub-areas compared to the control group, only right-left discrimination exhibited statistically significant change. 2. In gross motor development, the experimental group showed improvements in score compared to the control group, but it was not statistically significant. In fine motor development, the experimental group exhibited statistically significant improvements compared to the control group. In sub-area analysis, figure synthesis showed positive change. 3. In adaptive behavior development, post-experimental adaptive behavior scores were higher compared to pre-experimental scores with statistical significance. Furthermore, sub-areas emotional behavior, perception behavior, gross-fine motor function, oral-respiration function, motor behavior, motor planning, and adaptive response exhibited higher scores after SIT. In conclusion SIT was found to be partially effective in sensory and fine motor development, effective in all adaptive behavior areas, and not effective in gross motor development. Thus, this study has shown that SIT is an effective intervention for sensory development, fine motor development, and adaptive behavior for cerebral palsy children. But, for the effectiveness of SIT on gross motor development, further studies employing longer-time experiments are recommended.

• 재활복지
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• v.18 no.4
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• pp.207-220
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• 2014

The purpose of this study is to determine the parent-perceived effect of adaptive seating devices on the lives of infant or young children with physical and brain lesion disabilities(age 1-13y) and their families. Using the seating device for disabled parents of 42 people with disabilities who use FIATS-AS to investigate functional outcomes. All parents completed the FIATS-AS 4 times-2 times before and 2 times after their child received a new adaptive seating system. Repeated-measures analysis of variance detected significant mean differences among the FIATS-AS scores. Also to estimating the impact of the new seating intervention for the 3 age cohorts using the FIATS-AS scores. The FIATS-AS detected a significant interaction between age cohort and interview time. Providing adaptive seating devices has been found that the positive effects on guardians. The change was significant in 1~7 years of age. Environmental modification, such as seating and other assistive technology devices, may have an important role to play in the lives of young children with disabilities and their families.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.1B
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• pp.68-77
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• 2010

Wireless sensor networks are installed in various environments and collect sensing data through wireless links. The quality of a wireless link may be unstable due to environment causes and hardware performance in wireless sensor networks. Since the change of the link quality may cause data loss, sensor nodes need to adaptively estimate the change of the link quality. Also, the routing protocol should deal with this situation. In this paper, the adaptive link quality estimation and routing scheme in the large-scale wireless sensor networks are proposed. When the quality of a link is unstable, sensor nodes agilely estimate the quality of links, and the new route is selected. When quality of a link is stable, the link quality is occasionally estimated so that the energy consumption is reduced. Moreover, sensor nodes exchange less beacons in order to reduce an overhead in dense networks. In the case of sparse network, the sensor nodes exchange more beacons for finding a better route. We prove that the proposed scheme can improve the energy efficiency and reliability.

• Proceedings of the KIEE Conference
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• 1996.07b
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• pp.1034-1036
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• 1996

In this paper, an adaptive fuzzy logic controller is presented for auto-tunning of the scaling factors by using learning capability of neural networks. The proposed scheme consists of the FLC which includes the PI-type FLC and PD-type FLC in parallel form and the neural network which learns scale factors of FLC. Computer simulations were performed to illustrate the effectiveness of a proposed scheme. A proposed FLC controller was applied to the second order system and velocity control of the brushless DC motors. For the design of the FLC, tracking error, change of error, and acceleration error are selected as input variables of the FLC and three seal e factors were used in the parallel-type FLC. This scheme can be used to reduce the difficulty in the selection of the scale factors.

• Journal of Korea Multimedia Society
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• v.7 no.5
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• pp.755-765
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• 2004

Recently, the Internet-based distributed/parallel computing using many of idle hosts has been demonstrated its usefulness for processings of a large-scale task and involving several important issues. While executing a large-scale task, the realtime monitoring is required for adaptive strategy of the performance and state change of host. This paper provides the realtime monitoring and visualization on global computing infrastructure called PDP(Parallel Distributed Processing) which is a parallel computing framework implemented with Jana for parallel computing on the Internet.

• Journal of Environmental Policy
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• v.7 no.4
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• pp.35-55
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• 2008

Assessing vulnerability to climate change is the first step to take when setting up appropriate adaptation strategies. Adaptive capacity to climate change is the important factor comprising vulnerability. An adaptive capacity index in agricultural water management system was developed considering agricultural water supply and demand for rice production in Jeolla-do, Korea. The agricultural water supply was assumed to be equal to the amount of water stored in the major agricultural reservoirs, while data on the agricultural water demand was obtained from the dynamic simulation results by Korea Agriculture Corporation(KAC). The spatial unit for analysis was conducted at the county(Si, Gun, Gu) level and temporal scale was based on every month from 1991-2003. Adaptive capacity for drought stress index(ACDS index) was calculated as the percentage of data points where the irrigated water supply was greater than the crop water demand. The ACDS index was compared with SWSCI(Standard Water Storage Capacity Index) and the relationship showed high degree of fit($R^2$=0.84) using the exponential function, indicating that the developed ACDS index is useful for evaluating the status of the balance between agricultural water supply and demand, especially for the small sized agricultural reservoirs. This study provided the methodological basis for developing climate change vulnerability index in agricultural water system which is projected to be more frequently exposed to drought condition in the future due to climate change. Further research should be extended to the study on the water demand of the crops other than rice and to the projection of the change in ACDS index in the future.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 1996.06b
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• pp.285-309
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• 1996

Non oxide ceramics such as nitrides of transition metals have shown significant potential for future economic impact, in diverse applications in ceramic, aerospace and electronic industries, as refractory products, abrasives and cutting tools, aircraft components, and semi-conductor substrates amid others. Combustion synthesis has become an attractive alternative to the conventional furnace technology to produce these materials cheaply, faster and at a higher level of purity. However he process os highly exothermic and manifests complex dynamics due to its strongly non-linear nature. In order to develop an understanding of this process and to study the effect of operational parameters on the final outcome, numerical modeling is necessary, which would generated essential knowledge to help scale-up the process. the model is based on a system of parabolic-hyperbolic partial differential equations representing the heat, mass and momentum conservation relations. The model also takes into account structural change due to sintering and volumetric expansion, and their effect on the transport properties of the system. The solutions of these equations exhibit steep moving spatial gradients in the form of reaction fronts, propagating in space with variable velocity, which gives rise to varying time scales. To cope with the possibility of extremely abrupt changes in the values of the solution over very short distances, adaptive mesh techniques can be applied to resolve the high activity regions by ordering grid points in appropriate places. To avoid a control volume formulation of the solution of partial differential equations, a simple orthogonal, adaptive-mesh technique is employed. This involves separate adaptation in the x and y directions. Through simple analysis and numerical examples, the adaptive mesh is shown to give significant increase in accuracy in the computations.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
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• v.33 no.2
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• pp.35-40
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• 2022

Objectives: Restricted and repetitive behaviors (RRBs) are a core symptom in the diagnosis of autism spectrum disorder (ASD). The complexity of behavioral patterns has called for the creation of phenotypically homogeneous subgroups among individuals with ASD. The purpose of this study was 1) to investigate the different types of RRBs and 2) to explore whether subgroups created by RRBs would show unique levels of functioning in toddlers and young children with ASD. Methods: A total of 313 children with ASD, aged 12-42 months were included in the analysis. The Autism Diagnostic Interview-Revised was used to obtain information on the different types of RRBs by grouping 15 items into six categories. The Vineland Adaptive Behaviors Scale, a parent-reported questionnaire, was used to measure adaptive functioning. A portion of the children were analyzed separately for verbal-related RRBs based on their expressive language level. Two-step cluster analysis using RRB groups as features was used to create subgroups. Analysis of covariance while covarying for age and language was performed to explore the clinical characteristics of each cluster group. Results: Sensory-related RRBs were the most prevalent, followed by circumscribed interests, interest in objects, resistance to change, and repetitive body movements. A subset of the children was analyzed separately to explore verbal-related RRBs. Four cluster groups were created based on reported RRBs, with multiple RRBs demonstrating significant delays in adaptive functioning. Conclusion: Heterogeneity of RRBs emerges at a young age. The different patterns of RRBs can be used as valuable information to determine developmental trajectories with better implications for treatment approaches.