• Proceedings of the Korean Statistical Society Conference
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• 2005.11a
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• pp.167-173
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• 2005

This paper presents an autocorrelation test that is applicable to dynamic panel data models with serially correlated errors. The residual-based GMM t-test is a significance test that is applied after estimating a dynamic model by using the instrumental variable(IV) method and is directly applicable to any other consistently estimated residuals. Monte Carlo simulations show that the t-test has considerably more power than the $m_2$ test or the Sargan test under both forms of serial correlation (i.e., AR(1) and MA(1)).

• Journal of the Korean Statistical Society
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• v.34 no.4
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• pp.367-375
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• 2005

This paper presents an autocorrelation test that is applicable to dynamic panel data models with serially correlated errors. The residual-based GMM t-test is a significance test that is applied after estimating a dynamic model by using the instrumental variable (IV) method and is directly applicable to any other consistently estimated residuals. Monte Carlo simulations show that the t-test has considerably more power than the $m_2$ test or the Sargan test under both forms of serial correlation (i.e., AR(1) and MA(1)).

• Therapeutic Science for Rehabilitation
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• v.13 no.2
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• pp.85-94
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• 2024

Objective : This study aimed to determine the impact of an instrumental daily living activity program for adults with developmental disabilities on their daily living activities and quality of life (QOL). Methods : This study used a single-group pre-test-post-test experimental design. Participants comprised 17 adults with developmental disabilities from the Welfare Center for the Disabled. This program consisted of 10 sessions, including pre- and post-assessments, pertaining to training and education on grocery shopping, meal preparation and cleaning, home management, safety, and emergency management. The evaluation tools used in this study were the Quality of Life Questionnaire, Korean version of the Life Space Assessment (K-LSA), and Korean version of the Instrumental Activities of Daily Living (K-IADL). Results : There was a statistically significant difference in the QOL and K-IADL scores before and after the instrumental activities of daily living occupational therapy program, and there was no statistically significant difference in the K-LSA scores. Conclusion : This study confirmed that implementing an IADL program for adults with developmental disabilities had a positive impact on performance and QOL. For adults with developmental disabilities to participate in daily life and society, interventions for work participation, including training in activities of daily living, must be expanded.

• Communications for Statistical Applications and Methods
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• v.8 no.2
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• pp.499-505
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• 2001

Kim and Baek (2000) tested the spatial randomness for he earthquake occurrence in the Korean Peninsula by using the nearest-neighbor test statistics and empirical distribution functions. The K-function, however, has obvious advantages over the methods used in Kim and Baek (2000), such as it does not depend on the shape of the study region and is an effective summary of spatial dependence over a wide range of scales. We applied the K-function method for testing the randomness to both of the historical and the instrumental seismicity data. It was found that he earthquake occurrences for historical and instrumental seismicity data are not random and clustered rather than scattered.

• Journal of KSNVE
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• v.6 no.5
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• pp.679-684
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• 1996

The Instrumental Variable Method(IVM), modified from least square algorithm, is applied to parameter identification of a noise contaminated bearing test rig. The signal to noise ratio included in Frequency Response Function(FRF) can cause significant errors in parameter identification. Therefore, among several candidates of parameter identification method, results of the applied IVM were compared with noise-contaminated least square method. This study shows that the noise-contaminated least square method can have indonsistent accuracy depending on the degree of noise level, while the IVM has robuster performance to signal to noise ratio than least square method.

• Korean Journal of Food Science and Technology
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• v.16 no.3
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• pp.309-313
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• 1984

Rheological parameters which represent texture of chewing gum at each masticatory stage were selected by analysis of correlations among instrumental, sensory parameters and preferences. Sensory stiffness and instrumental puncture work were representative rheological parameters at initial stage, and sensory firmness and instrumental hardness at intermediate stage. The representative rheological parameters at final stage were sensory firmness and lift, and instrumental hardness, the slope of force-distance cruve of penetration test and springiness. An equation predicting consumer's preference and ideal texture profile of chewing gum with representative instrumental parameters were proposed.

• Horticultural Science & Technology
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• v.17 no.3
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• pp.341-343
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• 1999

Quality of 'Niitaka' pear fruit was evaluated by instrumental and sensory analysis in relation to storability. Fruits harvested at commercial maturity were stored in a common storage room or in a cold storage at $2^{\circ}C$. During storage, fruits were sorted by instrumental measurement of soluble solid content (SSC) and flesh firmness. Then, overall acceptability was evaluated by organoleptic test. Critical storage period was determined by sensory evaluation index for different storage methods. After 60 days of storage, eating quality was acceptable when flesh firmness was higher than $3.3kg/8mm{\emptyset}$. As for soluble solid contents, high eating quality was obtained when pear fruit contained soluble solids higher than $13.0^oBrix$. In 'Niitaka' pears, however, changes in soluble solid content seemed not to be an appropriate parameter to determine storability since SSC increased during both common and cold storage. Data of organoleptic test and postharvest changes in flesh firmness suggested that storability of 'Niitaka' pear fruit seemed to be 30 days in a common storage and 120 days in a refrigerated storage.

• Therapeutic Science for Rehabilitation
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• v.10 no.1
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• pp.115-127
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• 2021

Objective : The purpose of this study was to investigate the effect of telerehabilitation on executive function, activities of daily living, instrumental activities of daily living, and occupational performance in stroke patients. Methods : The participants of this study were 30 outpatients with stroke residing in community. Both groups underwent the intervention 3 times a week for a total of 18 sessions. For the experimental group telerehabilitation was administered at home to only fifteen participants in the experimental group schedule, and it was supervised by the caregiver. Fifteen people in the control group underwent only the traditional occupational therapy. Executive function and instrumental activities of daily living were evaluated using the Korean version of the Executive Function Performance Test (EFPT-K). The basic daily activities of living were assessed using the Modified Barthel Index (MBI). The Canadian Occupational Performance Measure (COPM) was used to evaluate the client-centered occupational performance. Results : After the intervention, the experimental and control groups showed improvements in executive function, instrumental activities of daily living and occupational performance. Occupational performance improved more significantly in the experimental group than in the control group. Conclusion : Telerehabilitation and occupational therapy positively affect executive function, instrumental activities of daily living and occupational performance of patients with stroke. We suggest that telerehabilitation combined with occupational therapy is more effective in improving the occupational performance of stroke patients.

• Journal of Korean society of Dental Hygiene
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• v.15 no.2
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• pp.325-332
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• 2015

Objectives: The purpose of this study was to investigate tooth whitening maintenance efficacy of several dentifrices containing effective ingredients for tooth whitening. Methods: Hydroxyapatite specimens(HAPs) staining was done by using modified Stookey's methods. HAPs were treated with 2.9% hydrogen peroxide containing strip for whitening, and were shaken with several dentifrice slurry(dentifrice 1 : artificial saliva 2) for 30 minutes. The HAPs were finally dipped in staining solution for an hour. Shaking and dipping were repeated 4 times and lightness values were measured by colorimeter at each step. In clinical test, test 4 dentifrice and control dentifrice were evaluated by 21 subjects for 2 months after receiving institutional review board(IRB) approval. Organoleptic(vita shade guide) and instrumental(SHADEEYE-NCC) evaluation were performed for whiteness change of teeth. Statistical analysis was performed using repeated measures ANOVA, Tukey's post hoc test and ${\chi}^2$-test(p<0.05). Results: All dentifrices showed statistical significance in comparison with control dentifrice containing sodium fluoride and test 4 dentifrice containing sodium pyrophosphate, sodium metaphosphate, candelilla wax, and sodium fluoride showed statistical significance in comparison with other dentifrices by inhibiting staining in vitro(p<0.05). In clinical test, test 4 dentifrice showed better effects than control dentifrice in organoleptic and instrumental evaluation in tooth whitening maintenance efficacy(p<0.05). The awareness toward tooth whitening maintenance efficacy for 2 months use showed that test 4 dentifrice was much better than control dentifrice, but did not show statistically significant(p>0.05). Conclusions: Dentifrice containing sodium pyrophosphate, sodium metaphosphate, candelilla wax and sodium fluoride was more effective in keeping teeth white.

• Therapeutic Science for Rehabilitation
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• v.4 no.2
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• pp.73-83
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• 2015

Objective: The purpose of this study was to examine the effect of the Spaced Retrieval Training (SRT) with Errorless learning on the elderly with Mild Cognitive Impairment (MCI)'s memory, Instrumental Activities Daily Living, Depression symptom. Methods: A single subject experimental research with ABA design was conducted in this study on the 78-years-old person who was enrolled in day-care center. The total experimental sessions were 16 which composed of 3 sessions for baseline, 10 sessions for intervention and 3 sessions for second baseline. K-Auditory Verbal Learning Test (K-AVLT) was measured for the memory each session. For the measurement of cognitive function, IADL, depression Symptom, Korean version of Montreal Cognitive Assessment (MoCA-K), Philadelphia Geriatric Center Instrumental Activities Daily Living (PGC IADL), Geriatric Depression Scale Korean Version (GDS-K) was measured at pre-post test. Results: Memory at the phase B was improved than Phase A. At the phase B, the scores trend was ascending, but after the intervention at the phase A', the scores trend was descending. The scores of MoCA-K were improved, PGC IADL were maintained, GDS-K were decreased. Conclusion: This results support the evidence of the SRT with EL on the elderly with MCI in the clinical setting. In the future, the correlation researches about MCI's memory and other functional factors will be needed for effective occupational therapy service.