• 정보과학회 논문지
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• 제42권5호
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• pp.551-557
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• 2015

ARM TrustZone을 이용한 기술은 새로운 임베디드 시스템의 가상화 연구로 관심을 끌고 있다. ARM TrustZone은 secure world와 normal world라는 두 개의 가상 실행 환경을 정의한다. 소프트웨어의 기능을 확장하기 위한 방법으로 ARM TrustZone 환경에서 world 간 통신은 중요하다. 그러나 현재의 모니터 모드의 소프트웨어는 world 간 통신을 충분히 지원하지 않고 있다. 본 논문에서는 ARM TrustZone을 이용한 각 world에서 구동되는 게스트 운영체제 간의 새로운 통신 메커니즘을 제시한다. 제안한 통신 메카니즘은 싱글코어와 멀티코어에서 양방향 world 간 통신을 지원한다. 본 논문에서는 ARM Cortex-A9 MPCore 기반의 NVIDIA Tegra3 processor를 사용하였고, 30MB/s이상의 통신 성능을 보여주었다.

• PNF and Movement
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• 제20권2호
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• pp.215-222
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• 2022

Purpose: The purpose of this study was to compare the effects of passive scapular upward rotation and posterior tilt and active scapular posterior tilt on the muscle activity of the upper trapezius (UT), lower trapezius (LT), and serratus anterior (SA). Methods: Fifteen healthy subjects performed general arm elevation, arm elevation with passive scapular upward rotation and posterior tilt, and arm elevation with active scapular posterior tilt. For active scapular posterior tilt, the subjects were trained in this movement using visual biofeedback and a motion sensor. During each arm elevation condition, electromyography was used to measure the muscle activity of the UT, LT, and SA. The measured data were analyzed using a one-way repeated ANOVA. Results: LT muscle activity was significantly increased during arm elevation with active scapular posterior tilt compared to both general arm elevation and arm elevation with passive scapular upward rotation and posterior tilt (p < 0.05). SA muscle activity was greater during arm elevation with passive scapular upward rotation and posterior tilt than during general arm elevation (p < 0.05). There was no significant change in UT muscle activity among the tested arm elevation conditions (p > 0.05). Conclusion: Performing arm elevation with active scapular posterior tilt and performing arm elevation with passive scapular upward rotation and posterior tilt may be useful strategies for increasing muscle activation of the LT and SA, respectively.

• 대한임베디드공학회논문지
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• 제8권1호
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• pp.25-29
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• 2013

Recently ARM processor's processing power has been increasing rapidly as it has been applied to consumer electronics products. Because of its computing power and low power consumption, it is used to various embedded systems.( including vision processing systems.) Embedded linux that provides well-made platform and GUI is also a powerful tool for ARM based embedded systems. So short period to develop is one of major advantages to the ARM based embedded system. However, for real-time date processing applications such as an image processing system, ARM needs additional equipments such as FPGA that is suitable to parallel processing applications. In this paper, we developed an embedded system using ARM processor and FPGA. FPGA takes time consuming image preprocessing and numerical algorithms needs floating point arithmetic and user interface are implemented using the ARM processor. Overall processing speed of the system is 60 frames/sec of VGA images.

• Journal of Mechanical Science and Technology
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• 제19권spc1호
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• pp.444-451
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• 2005

The analysis of human arm motion during steering maneuver is carried out for investigation of man-machine interface of driver and steering system Each arm is modeled as interconnection of upper arm, lower arm, and hand by rotational joints that can properly represents permissible joint motion, and both arms are connected to a steering wheel through spring and damper at the contact points. The joint motion law during steering motion is determined through the measurement of each arm movement, and subsequent inverse kinematic analysis. Combining the joint motion law and inverse dynamic analysis, joint stiffness of arm is estimated. Arm dynamic analysis model for steering maneuver is setup, and is validated through the comparison with experimentally measured data, which shows relatively good agreement. To demonstrate the usefulness of the arm model, it is applied to study the effect of steering column angle on the steering motion.

• 한국정보통신학회논문지
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• 제13권7호
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• pp.1335-1343
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• 2009

본 논문에서 진행한 연구는 고속의 ARM 아키텍처 기반의 ARM11 코어를 적용한 최신 MPU인 S3C6400을 이용한 플랫폼을 구현하고 구현된 플랫폼에 OS로서 리눅스를 포팅하여 Handheld 타입의 가스 센서용 플랫폼 구현에 관한 연구이다. 무선으로 데이터를 전송받기 위하여 블루투스를 이용한 네트워크 환경을 구축하였다. QT/embedded를 사용하여 리눅스 상에서 유연한 어플리케이션 개발 환경을 구축하여 관련된 프로그램을 작성하였다.

• 대한임베디드공학회논문지
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• 제3권1호
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• pp.19-24
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• 2008

To reduce time-to-market, more and more embedded system developers and system-on-chip designers rely on microprocessor-based design methodology. ARM processor has been a major player in this industry over the last 10 years. However, there are many restrictions on developing embedded software using ARM processor in the early design stage. For those who are not familiar with embedded software development environment or who cannot afford to have an expensive embedded hardware equipment, testing their software on a real ARM hardware platform is a challenging job. To overcome such a problem, we have designed VMA (Virtual ARM Machine), which offers easier testing and debugging environment to ARM based embedded system developers. Major benefits that can be achieved by utilizing a virtual ARM platform are (1) reducing development cost, (2) lowering the entrance barrier for embedded system novices, and (3) making it easier to test and debug embedded software designs. Unlike many other purely software-oriented ARM simulators which are independent of real hardware platforms, VMA is specifically targeted on SYS-Lab 5000 ARM hardware platform, (designed by Libertron, Inc.), which means that VMA imitates behaviors of embedded software as if the software is running on the target embedded hardware as closely as possible. This paper will describe how VMA is designed and how VMA can be used to reduce design time and cost.

• 한국산학기술학회논문지
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• 제11권7호
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• pp.2528-2533
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• 2010

본 논문은 대방미사일(ARM: Anti Radiation Missile)로부터 레이다를 보호하기 위한 전파회피기술의 분석에 사용될 시뮬레이터 개발에 관한 것이다. 제시된 시뮬레이터는 전파회피를 위해 널리 사용되는 디코이(Decoy) 안테나의 효과적인 배치와 ARM 수신기에 수신되는 전파의 특성 분석이 가능하다. 그리고 디코이 안테나의 배치 효과를 검증하기위해 ARM 수신기에 도달하는 디코이 안테나 신호의 위상과 진폭을 분석하였다. 또한 다수 디코이 안테나를 사용하는 경우 ARM의 공격효과를 다양하게 분석하였으며 제안된 시뮬레이터는 ARM 방어를 위한 효과적인 디코이 배치에 유용하게 활용 될 것이다.

• 대한물리치료과학회지
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• 제15권1호
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• pp.39-45
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• 2008

This study was undertaken to identify the influence which affect on gait speed and energy consumption regarding putting on arm sling during gait of the 40 hemiplegic patients selected from University Hospital and rehabilitation center in seoul during two months. The analysis of data was performed using the paired samples ttest to compare the differences of gait velocity, heart rate, oxygen consumption and oxygen cost in gait of preand post－ arm sling. The results of this study were as follows; 1. When comparing the result before putting on arm sling in the gait of hemiplegic patient, gait velocity after putting on arm sling was statistically significantly increased(p<.05). 2. When comparing the result before putting on arm sling in the gait of hemiplegic patient, heart rate after putting on arm sling was statistically significantly decreased(p<.05). 3. When comparing the result before putting on arm sling in the gait of hemiplegic patient, oxygen consumption per weight after putting on arm sling was statistically significantly decreased(p<.05). 4. When comparing the result before putting on arm sling in the gait of hemiplegic patient, oxygen consumption rate per weight after putting on arm sling was statistically significantly decreased(p<.05). When putting together the above result, the gait with arm sling in comparison with the gait without arm sling was to increase gait velocity, decrease heart rate, decrease oxygen consumption and was finally to decrease energy consumption in the gait of hemiplegic patient.

• 대한정형도수물리치료학회지
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• 제28권1호
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• pp.71-80
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• 2022

Background: This study investigated the effect of robot-assisted arm training on muscle activity of arm and weight bearing in stroke patients. Methods: The study subjects were selected 20 stroke patients who met the selection criteria. 10 people in the robot-assisted arm training group and 10 people in the task-oriented arm training group were randomly assigned. The experimental group performed robot-assisted arm training, and the control group performed task-oriented arm training for 6 weeks, 5 days a week, 30 minutes a day. The measurement tools included surface electromyography and smart insole system. Data were analyzed using independent sample t-test and the paired sample t-test. Results: Comparing the muscle activity of arm within the group, the experimental group and the control group showed significant differences in muscle activity in the biceps brachii, triceps brachii, anterior deltoid, upper trapezius, middle trapezius, and lower trapezius. Comparing the muscle activity of arms between the groups, the experimental group showed significant difference in all muscle activity of arm compared to the control group. Comparing the weight bearing within the groups, the experimental group showed significant difference in the affected side and non-affected side weight bearings and there were significant differences in anterior and posterior weight bearing. The control group showed significant difference only in the non-affected side weight bearing. Comparing the weight bearings between groups, the experimental group showed significant difference in the affected side and non-affected side weight bearings compared to the control group. Conclusion: This study confirmed that robot-assisted arm training applied to stroke patients for 6 weeks significantly improved muscle activity of arm and weight bearing. Based on these results, it is considered that robot-assisted arm training can be a useful treatment in clinical practice to improve the kinematic variables in chronic stroke patients.

• 대한기계학회논문집B
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• 제27권2호
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• pp.243-250
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• 2003

The extinction behavior and the unsteady response of augmented reduced mechanism(ARM) have been investigated by adopting an OPPDIF code and a numerical solver for the flamelet equations. By comparing the performance of the ARM based on Miller and Bowman's mechanism(MB-ARM) with that of the ARM based on GRI-Mech 3.0(GRI-3.0-ARM), it is identified that the MB-ARM is more suitable for the unsteady calculation because it is relatively less stiff than GRI-3.0-ARM during an ignition process. The steady results using the MB-ARM, which is modified to predict reasonably the extinction point of experiment, are in excellent agreement with those from full mechanism. Under the sinusoidal transient disturbances of scalar dissipation rate, the unsteady responses of the flame temperature and species concentrations using a modified MB-ARM show in very close agreement with those from full mechanism. It is presumed that above modified MB-ARM is very suitable for the unsteady simulation of turbulent flames because it gives not only a low computational cost but also a good prediction performance for flame structure, extinction point and unsteady response.