• Journal of the Korean Society for Precision Engineering
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• v.18 no.8
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• pp.174-181
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• 2001

Nowadays, the improvement and development of Multi-media and information & communication technology is rapidly processed. They need large data storage capacity. So that, many studies and researches in data storage have been carried out. According to them, the data storage capacity has been increased. But the limitation of storage capacity is happened for several problems. One of them is spot & pit size in optical and magnetic data storage and another is the resolution of actuators. The problems in spot & pit size are covered by new data storage methods-- for examples, AFM(Atomic Force Microscopy), MO(Magneto-optical) system, and NFR(Near-Field decoding) system etc. But the resolution limit of an actuator was not developed and doesn\`t follow up the development of spot & pit size. Because of them, we should improve a resolution of an actuator. Especially, in this paper an actuator if studied and designed for NFR (in using SIL(Solid Immersion Lens) system. It is a dual stage actuator, which consists of a Fine actuator and a Coarse actuator. and should desire 100nm accuracy. Its actuating force generation method is VCM(Voice Coil Motor). The Fine actuator is composed of 4-leaf springs and a bobbin wrapped by coil. The Coarse actuator has Coils and 3-Roller bearings. Also, The Characteristics of designed actuator for NFR system is estimated by Sine-Swept mode and LDV(Laser Doppler Vibro-meter).

• Child Health Nursing Research
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• v.15 no.1
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• pp.34-41
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• 2009

Purpose: In this study, a Checklist for Infant and Child Developmental Screening (CICDS) was designed for use by primary pediatric health care providers to identify infants and children with developmental delays. Method: Each Item of the CICDS was constructed referring to existing tools. In 5 public health centers of B city, 500 infants and children were selected at the age of 2, 4, 6, 12, & 18 months and assessed between October and December 2006, CICDS and the Korea Denver II were compared to assesses the validity of the CICDS. Results: The CICDS consisted of 30 items in 4 areas; Personal-social, Fine motor-adaptive, Language, Gross motor. The results of the CICDS correlated significantly with the result of Korea Denver II at each month of age. (r=0.19; p<.01). Of the 500 infants and children, 148 were "suspect" for development delays (sensitivity of 96%, specificity 73%). On the CICDS, 74.6% of children received same result as Denver II. In discriminant analysis, 89.9% of children were identified correctly by CICDS (p<.01). Conclusion: CICDS could be a screening procedures to quickly and reliably identify infants with developmental delays. It also provides a mean of recording measurements of development characteristics.

• Journal of The Korean Society of Integrative Medicine
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• v.11 no.3
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• pp.49-57
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• 2023

Purpose : This study aimed to systematically review the correlation between hand dexterity and cognitive function in the elderly, and summarize various evaluation tests and results analysis methods for manual dexterity tests applied to this population. Methods : We searched published studies in the Korean Studies Information Service System and PubMed databases from January 2013 to March 2023. The main keywords used were "dexterity," "fine motor," "elderly," "cognitive function," and "correlation." A total of 10 studies were selected for analysis from the 1,524 searched articles. The included studies consisted of a cohort study, a longitudinal study, and eight cross-sectional studies which were analyzed for patients, intervention, comparison, and outcomes. Results : Analyzing the qualitative level of 10 studies, 8 articles (80%) were non-randomized two-group studies that provided level II evidence whereas the remaining 2 studies (20%) were non-randomized single-group studies (level III evidence). Therefore, these results indicated that the level of evidence in this field is generally high. The Purdue pegboard test was the most commonly used evaluation test for manual dexterity, and velocity speed was the most frequently employed analysis method. Results indicated that there were significant differences in manual dexterity test between the normal elderly, those with mild cognitive impairment, or dementia. Conclusions : These results can be used as a basis for selecting dexterity test evaluation items and methods to analyze it in the elderly while screening for cognitive impairment. In addition, this study highlights potential areas for future research on the development of manual dexterity evaluation tools and techniques for analysis and the need for more reliable and valid methods for assessing cognitive function in the elderly.

• Clinical and Experimental Pediatrics
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• v.63 no.11
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• pp.438-446
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• 2020

Background: Most developmental screening tools in Korea are adopted from foreign tests. To ensure efficient screening of infants and children in Korea, a nationwide screening tool with high reliability and validity is needed. Purpose: This study aimed to independently develop, standardize, and validate the Korean Developmental Screening Test for Infants and Children (K-DST) for screening infants and children for neurodevelopmental disorders in Korea. Methods: The standardization and validation conducted in 2012-2014 of 3,284 subjects (4-71 months of age) resulted in the first edition of the K-DST. The restandardization and revalidation performed in 2015-2016 of 3.06 million attendees of the National Health Screening Program for Infants and Children resulted in the revised K-DST. We analyzed inter-item consistency and test-retest reliability for the reliability analysis. Regarding the validation of K-DST, we examined the construct validity, sensitivity and specificity, receiver operating characteristic curve analysis, and a criterion-related validity analysis. Results: We ultimately selected 8 questions in 6 developmental domains. For most age groups and each domain, internal consistency was 0.73-0.93 and test-retest reliability was 0.77-0.88. The revised K-DST had high discriminatory ability with a sensitivity of 0.833 and specificity of 0.979. The test supported construct validity by distinguishing between normal and neurodevelopmentally delayed groups. The language and cognition domain of the revised K-DST was highly correlated with the K-Bayley Scales of Infant Development-II's Mental Age Quotient (r=0.766, 0.739), while the gross and fine motor domains were highly correlated with Motor Age Quotient (r=0.695, 0.668), respectively. The Verbal Intelligence Quotient of Korean Wechsler Preschool and Primary Scales of Intelligence was highly correlated with the K-DST cognition and language domains (r=0.701, 0.770), as was the performance intelligence quotient with the fine motor domain (r=0.700). Conclusion: The K-DST is reliable and valid, suggesting its good potential as an effective screening tool for infants and children with neurodevelopmental disorders in Korea.

• The Journal of Korean Physical Therapy
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• v.29 no.4
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• pp.211-217
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• 2017

Purpose: The purpose of this study was to trace the development of premature babies who had undergone neurodevelopmental treatment in the neonatal intensive care unit and to identify the effects of early neurodevelopmental treatment on the development of premature babies. Methods: Fifty-one premature babies, who had been hospitalized in the neonatal intensive care unit and received an infant motor performance test and Bayley scales-III evaluation of their developments during the six months of corrected age were included. They were divided into three groups: the intervention group (n=16), control group (n=23), and comparison group (n=12), depending on the risk of developmental delays and the existence of an intervention. The results of this study were analyzed using SPSS 22.0 for windows. The statistical significance level was set at ${\alpha}=0.05$. Results: Regarding the infant motor performance test scores for each group before the intervention, at two weeks after the start of intervention, and at post-conception of 40 weeks, the intervention group showed a significantly higher improvement than the control or comparison group (p<0.01). With respect to the Bayley scales-III at the corrected age of six months, the intervention group exhibited statistically significant differences from the control group in the domains of language and fine movements (p<0.01). Conclusion: The findings of this study could confirm that the early neurodevelopmental treatment of premature babies in the neonatal intensive care unit has continuous effects on the development of premature babies even after being discharged from the hospital.

• Korean Journal of Artificial Intelligence
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• v.8 no.2
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• pp.1-5
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• 2020

Children's home accidents are less common than in the past. However, safety accidents continue to occur due to carelessness of the parents. To solve the problem, there are fall prevention screens that can withstand the weight of children, and safety railings that can be adjusted directly to solve the problem. However, these have disadvantages such as stability, convenience, and damage to the landscape. In this paper, we developed an automatic safety accident prevention fence system that can be installed on a window using Arduino, eliminating the disadvantages of previous safety accident prevention products. This system measures the height of a person standing in front of the fence and the distance between the person and the fence with two infrared sensors and moves automatically using a motor. In addition, in accordance with the U-Healthcare society, users can check the temperature, humidity, and fine dust concentration of the external environment through mobile. Each information can be obtained through DHT 11 sensor, fine dust concentration sensor, and Bluetooth connected toArduino. These can help the user's health care.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.480-480
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• 2000

In this paper, we proposed a fuzzy-neuro controller to control the speed of wound rotor induction motor with slip energy recovery. The speed is limited at some range of sub-synchronous speed of the rotating magnetic field. Control speed by adjusting resistance value in the rotor circuit that occurs the efficiency of power are reduced, because of the slip energy is lost when it passes through the rotor resistance. The control system is designed to maintain efficiency of motor. Recently, the emergence of artificial neural networks has made it conductive to integrate fuzzy controllers and neural models for the development of fuzzy control systems, Fuzzy-neuro controller has been designed by integrating two neural network models with a basic fuzzy logic controller. Using the back propagation algorithm, the first neural network is trained as a plant emulator and the second neural network is used as a compensator for the basic fuzzy controller to improve its performance on-line. The function of the neural network plant emulator is to provide the correct error signal at the output of the neural fuzzy compensator without the need for any mathematical modeling of the plant. The difficulty of fine-tuning the scale factors and formulating the correct control rules in a basic fuzzy controller may be reduced using the proposed scheme. The scheme is applied to the control speed of a wound rotor induction motor process. The control system is designed to maintain efficiency of motor and compensate power factor of system. That is: the proposed controller gives the controlled system by keeping the speed constant and the good transient response without overshoot can be obtained.

• Clinical and Experimental Pediatrics
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• v.52 no.7
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• pp.772-777
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• 2009

Purpose : We aimed to compare the effectiveness of 2 developmental tests-Korean Infant and Child Development Test (KICDT) and Korean Bayley Scale of Infant Development-II (K-BSID-II)-in the assessment of children with developmental delay. Methods : Twenty-eight children with suspected developmental delay, who visited the Department of Pediatrics in Asan Medical Center from February 2007 to June 2008 were enrolled. They were examined using both KICDT and K-BSID-II. The results of the tests were compared on the basis of 2 parameters: age group of the children and detection of organic brain lesion on magnetic resonance imaging (MRI). The correlation between the results of the 2 tests was analyzed using SPSS. Further, intraclass correlation coefficient was calculated using SAS to examine consistency between the results of the 2 tests. Results : The mental developmental index of K-BSID-II showed significant correlation with every KICDT score (P<0.01). The psychomotor developmental index of K-BSID-II was also significantly correlated with every KICDT score except the fine motor score (P<0.01). The mental developmental index of K-BSID-II showed significant correlation [Editor20] with the KICDT gross motor, fine motor, and language scores (P<0.05). Further, there was significant correlation between the psychomotor developmental index of K-BSID-II and the KICDT gross motor score (P<0.05). Conclusion : There was significant [Editor21]correlation between the results of KICDT and K-BSID-II for infants and children with developmental delay. Although our results suggest that KICDT is useful in assessing developmental delay, further research would be needed to standardize this test.

• Journal of Korea Foundry Society
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• v.28 no.4
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• pp.166-169
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• 2008

This study deals about the development of fusible core with low melting temperature by addition of ceramic particles. A new concept of salt core was introduced to produce an integrated casting part having a complicated inner shape or requiring under-cut in high pressure die casting or squeeze casting process. The mechanical properties of fusible core were improved due to the addition of ceramic particles which helped to produce fine microstructure. The new technology for the preparation of new fusible core materials which possess high compression strength was established. Addition of ceramics particles increased the mechanical properties of fusible core materials. There was an increasing relationship between percentage of ceramic particles and mechanical strength was existed up to 60%.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.267-268
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• 2006

Cam mechanisms are one of the most popular devices for generating irregular motion and are widely used in many industrial areas. The purpose of this study is the development of high precision measuring system fur measurement data acquisition and analysis of a manufactured cam profile. The developed system is composed of servo motor, CNC controller, rotary encoder, and laser interferometer And also, this system is non-contact measuring type. The developed system takes only 5 minutes to measure a cam profile and to analyze the measuring data while the CMM(coordinate measuring machine) takes about 1 hours even by a skilled operator.