• Restorative Dentistry and Endodontics
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• v.38 no.1
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• pp.31-35
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• 2013

Objectives: This study compared the cyclic fatigue resistance of nickel-titanium (NiTi) files obtained in a conventional test using a simulated canal with a newly developed method that allows the application of constant fatigue load conditions. Materials and Methods: ProFile and K3 files of #25/.06, #30/.06, and #40/.04 were selected. Two types of testing devices were built to test their fatigue performance. The first (conventional) device prescribed curvature inside a simulated canal (C-test), the second new device exerted a constant load (L-test) whilst allowing any resulting curvature. Ten new instruments of each size and brand were tested with each device. The files were rotated until fracture and the number of cycles to failure (NCF) was determined. The NCF were subjected to one-way ANOVA and Duncan's post-hoc test for each method. Spearman's rank correlation coefficient was computed to examine any association between methods. Results: Spearman's rank correlation coefficient (${\rho}$ = -0.905) showed a significant negative correlation between methods. Groups with significant difference after the L-test divided into 4 clusters, whilst the C-test gave just 2 clusters. From the L-test, considering the negative correlation of NCF, K3 gave a significantly lower fatigue resistance than ProFile as in the C-test. K3 #30/.06 showed a lower fatigue resistance than K3 #25/.06, which was not found by the C-test. Variation in fatigue test methodology resulted in different cyclic fatigue resistance rankings for various NiTi files. Conclusions: The new methodology standardized the load during fatigue testing, allowing determination fatigue behavior under constant load conditions.

• Physical Therapy Rehabilitation Science
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• v.9 no.2
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• pp.120-130
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• 2020

Objective: This study was conducted to identify the clinical usefulness, validity, and reliability of the Spirokit, a device that combines the pulmonary function test (PFT) and respiratory muscle strength (RMS) test. Design: Cross-sectional study. Methods: Forty young adults (male: 23, female: 17) participated in a PFT and a RMS test. The concurrent validity for pulmonary function was assessed by comparing data obtained from MicroQuark and the Spirokit and the agreements between the MicroRPM and the Spirokit for RMS were compared. The test-retest reliability of the Spirokit was determined by comparing data obtained from the first and second sessions. The test and retest were performed at the same time after one day for the PFT and RMS test. Validity was estimated using intraclass correlation coefficients (ICCs), and by calculating 95% limits of agreement (LoA). To estimate interrater reliability, ICCs were calculated. Results: The Spirokit showed a high agreement intra class coefficient (ICC [2, 1]): 0.978-0.999, 95% limits of agreements (95% LOA): -0.798 to 0.847 with MicroQuark. It also showed a high level of concordance ICC (2, 1): 0.992 to 0.993, 95% LOA: -9.313 to 11.169 with MicroRPM. The test-retest reliability of the Spirokit was analyzed using ICC (2, 1), and showed a high level of reliability (ICC [2,1]=0.960 to 0.998). Standard error of measurement % (SEM%) was 0.12% to 3.39%, and minimum detectable change% (MDC%) was 0.02% to 3.79%, indicating high level of reliability. Conclusions: The Spirokit is a device with high validity and reliability that can be used to simultaneously measure PFT and RMS tests.

• Journal of Biomedical Engineering Research
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• v.34 no.2
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• pp.69-72
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• 2013

The goal of this study is to develop test method for evaluating the drug eluting properties of drug eluting stents (DES). PBS and the detergent solutions, presented by each DES manufacturer, were used for drug release of DES coated with paclitaxel, zotarolimus and everolimus. The drugs which are coating DES were not released by PBS but released by the detergent solutions, finally paclitaxel 83.38%, zotarolimus 103.85% and everolimus 115.78%. It seems that the use of the detergents is necessary in order to release the drugs because those drugs are extremely hydrophobic. In conclusion, using of detergent solutions presented by each manufacturer were suitable for evaluating the drug eluting property of drug eluting stent.

• Proceedings of the KIEE Conference
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• 2008.11a
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• pp.373-375
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• 2008

TTCN-3(Testing & Test Control Notation Version 3) defined in EISI(2001) are the standardized test specification and test implementation language of applicable for all kinds of black-box testing for reactive and distributed system, telecom systems, Mobile system, Internet, CORBA based system, java, XML, etc. This paper using the TTCN-3 on an Electric Power IT Protocol DLMS(Device Language Message Specification) standards for the implementation of the device equipment test the suitability of the protocol.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.24 no.12
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• pp.147-155
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• 2010

We studied on performance improvement of TTM(TI21 Test Meter) that is test and diagnosis devices for jointless audio frequency track circuit on Korean electric railway TI21 standard. Upgraded devices is AD-TTM(Advanced TI21 Test Meter). This can measure alternating frequency USB(Upper signal band) and LSB(Lower signal band). In the audio frequency track circuit, ${\pm}17[Hz]$ of nominal frequency are demodulated and supplied to track relay through AND gate. It is important that measurement function which is error between USB and LSB. Need of AD-TTM will stand out in the electric railway system because this is simple and accurate rather than the former device.

• Journal of Ocean Engineering and Technology
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• v.21 no.1 s.74
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• pp.69-74
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• 2007

This paper is concerned about the dynamic analysis of an underwater test miner, which operates on cohesive soil. The test miner consists of tracked vehicles and a pick-up device. The motion of the pick-up device, relative to the vehicle chassis, is controlled by two pairs of hydraulic cylinders. The test miner is modeled by means of commercial software. A terramechanics model of cohesive soft soil is implemented with the software and applied to a dynamic analysis of the test miner model. The dynamic responses of the test miner are studied with respect to four different types of terrain conditions.

• Proceedings of the KSR Conference
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• 2011.05a
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• pp.1440-1444
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• 2011

Memory-device is one of the auxiliary components of point-switch machine; connecting front-rod and tongue-rail. The right side and left side of memory-device are different from each other. When there would be a derailing accident of rolling stock or motor-car, the memory-device properly bends and protects the internal of point-switch machine. Memory-device is one of the important site maintenance spare parts. Memory-device for each of right and left side should be secured so that they can be installed on correct side during an exchange work. This study suggests the development of memory-device with different left and right side and the performance test of it. The study intends to contribute in the convenience improvement of maintenance by improving the unification of memory-device.

• JSTS:Journal of Semiconductor Technology and Science
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• v.14 no.3
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• pp.339-344
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• 2014

This paper presents a novel bipolar junction transistor (BJT) based electrostatic discharge (ESD) protection device. This protection device was designed for 20V power clamps and fabricated by a process with Bipolar-CMOS-DMOS (BCD) $0.18{\mu}m$. The current-voltage characteristics of this protection device was verified by the transmission line pulse (TLP) system and the DC BV characteristic was verified by using a semiconductor parameter analyzer. From the experimental results, the proposed device has a trigger voltage of 29.1V, holding voltage of 22.4V and low on-resistance of approximately $1.6{\Omega}$. In addition, the test of ESD robustness showed that the ESD successfully passed through human body model (HBM) 8kV. In this paper, the operational mechanism of this protection device was investigated by structural analysis of the proposed device. In addition, the proposed device were obtained as stack structures and verified.

• Journal of the Korean Society of Physical Medicine
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• v.8 no.4
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• pp.637-645
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• 2013

PURPOSE: The purpose of this study was to examine the effect of using a suspension device for arm reaching activity on trunk stability and gross motor function of children with spastic diplegia cerebral palsy. METHODS: The subject in this study consisted of 11, GMFCS(Gross Motor Function Classification System) III~IV children with spastic diplegia cerebral palsy, all of whom agreed to participate in the study. All subjects were divided into two groups: the experimental group using a suspension device, and the control group using no suspension device. For each group, a thirty-minute intervention was done twice per week during 8 weeks. Before and after intervention, each test was measured using TIS(Trunk Impairment Scale), GMFM (Gross Motor Function Measure) and PRT(Pediatric Reaching Test) to change trunk stability, gross motor function and arm reaching activity. The data were analyzed with the Wilcoxon signed rank test. RESULT: All two groups had a meaningful increase in GMFM-Sit data measured before and after intervention. The experimental group had a significant increase from an average of 78.83 to an average of 84.83 in GMFM-Crawling. For both groups, there was a substantial increase in the change in sitting position and arm reaching. CONCLUSION: According to the results of this study, the arm reaching activity using suspension device had an effect on trunk stability and gross motor function and it changed arm reaching activity.

• 한국HCI학회:학술대회논문집
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• 2007.02b
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• pp.512-517
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• 2007

다양한 디지털 가전제품을 제조하는 회사들은 초기에 제품 하나하나에 제품의 사용경험을 담는데 비중을 높여 개발을 하였다. 하지만 제품이 알려지고 종류가 많아지면서 각 제품들을 아우르는 사용자 경험요소 통합화가 필요하게 되었다. 이에 다양한 화면 사이즈와 Input Device를 가진 Handheld Device들 간의 일관된 사용 경험(user experiences)을 제공하는 것을 목적으로 하는 연구가 진행되었다. 대상이 된 제품들은 Digital Media Broadcasting의 수신, Multimedia 파일이 재생, 파일 creation 등이 가능한 Handheld Devices였고, 각 제품들은 특정 기능에 충실한 UI를 구현하고 있다는 특징이 있다. 따라서, 기존 제품의 사용성을 저해하지 않는 수준의 표준화가 필요하며 기존 UI 사용성과 표준화 UI 사용성 간의 조화가 중요 하였다. 기존 제품의 개별 특징을 분석하고 Handheld Device의 사용자 요구사항을 조사를 통해 사용경험 요소를 발굴하고 Navigation, Menu Hierarchy, Screen Layout 등의 설계를 통해 Prototype 개발을 하고 Usability Test를 통해 보완을 하였다. Usability Test는 한국, 미국, 영국, 중국 4개국에서 광범위한 사용자 조사가 이루어졌다. 국가 선정은 제품의 주요 시장 및 각 대륙을 대표하는 기준으로 선정되었다. 사용자 그룹은 연령, 지식 수준, 성별에 구분되었고 Web Survey 1000명, Usability Test는 각 국가별 총 100명이 넘는 참석자에 의한 데이터 분석이 이루어 졌다. 이렇게 조사된 데이터를 바탕으로 UI 사용경험 요소를 정의하고 제품의 공통 가이드와 개별 가이드를 개발하는 일련의 프로세스를 확립하고 검증하였다. 본 논문을 통해 대상 제품들의 다양한 특성을 살리면서도 user Interface의 일관성 원칙을 설립하기 위해 시도했던 방법과 과정을 기술하고, 이 과정을 통해서 얻은 결과와 실제적인 경험을 소개한다.