• 한국화재소방학회논문지
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• 제12권4호
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• pp.3-12
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• 1998

이 연구는 인간의 중요한 행동습성 중의 하나언 좌회전숨성윷 건축설계에 고려활 경우, 고총건 불의 지상총 피난계단은 좌회전계판(피난층으로 내려갈 때 좌회전하여 내려가도록 설계원 계딴) 으료 설계하는 것이 재실자가 보다 더 안전하고 빠료게 피난하는 데 효과적이라는 것윷 현장조사 및 실험을 통하여 규명하고자 한 것이다. 2 20충 규모의 고층건불윷 이용하여 펴난자가 펴난총으로 내려갈 때의 펴난속도를 측정한 결과, 오른손잡이의 경우는 좌회전계단의 사용이 우회전계탄(피난층￡로 내려갈 때 우회전하여 내려가 도흑 설계된 계란)의 사용시보다 편하고 빠른 반면, 왼손잡이의 경우는 우회전계란의 사용이 좌회 전계딴의 사용시보다 편하고 빠르다는 것윷 확인하였다, 그려고 우려나라논 94% 이상의 사람이 오른손잡이인 것으로 조사되었다 그러나 현재 우려나라 고층건울의 지상총 펴난계단은 조사결과 7 76% 이상이 우회전계딴임을 알 수 있었다. 이렇게 잘못 설계원 펴난계딴의 실태를 감안해 볼 때 이의 시정을 위해서는 판원볍규의 피난계딴 구조기푼에 고총건물의 지상층 펴난계딴은 좌회전계 딴요로 설계하도록 규정할 펼요가 있다.

• Journal of Electrical Engineering and Technology
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• 제11권6호
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• pp.1777-1782
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• 2016

A compact and broadband balun is designed using a conventional right-handed transmission line (RHTL) and a left-handed transmission line (LHTL) with lumped elements only. The proposed balun maintains a phase difference of $180^{\circ}{\pm}12^{\circ}$ at the output ports for the frequency range of 1.27 GHz-2.69 GHz. Nevertheless, the circuit size is merely $9.5mm{\times}12.7mm$. To verify the performance of the proposed balun, we attached it to a dipole-type antenna and observed that the return loss is greater than 10 dB for the frequency range between 1.86 GHz and GHz. The radiation pattern and peak gain are similar to those of the dipole antenna with a conventional balun.

• International Journal of Contents
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• 제11권3호
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• pp.63-68
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• 2015

A novel unit cell for a high pass filter was designed based on a composite right/left-handed structure that uses a folded coplanar waveguide. The equivalent circuit model for the unit cell was extracted from the geometry of the unit cell, and the effect of each main parameter of the unit cell was analyzed. The equations to calculate the immittance values of the equivalent circuit elements were formulated, and moreover, the dispersion characteristics and energy the distributions of the electromagnetic fields were simulated to determine the characteristics of the composite right/left-handed structure. Finally, the high pass filters were implemented as a series of the proposed unit cells. We show that the experimental results were in good agreement with those obtained from the simulation. Thus, the high pass filter was found to achieve a baseband insertion loss of 3 dB and a stopband attenuation of 70 dB.

• Journal of electromagnetic engineering and science
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• 제17권1호
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• pp.9-13
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• 2017

In this work, a broadband composite right/left-handed (CRLH) half-mode substrate integrated waveguide (HMSIW) quadrature Wilkinson power divider is proposed. The proposed CRLH-HMSIW quadrature power divider includes a microstrip Wilkinson power divider on the transition structure between the microstrip and HMSIW, and two thru transmission lines for the HMSIW and the CRLH-HMSIW. The measured amplitude, phase difference and isolation between the two output ports of the proposed structure have 1 dB, ${\pm}5^{\circ}$ and less than -15 dB in a wide frequency range of 4.1-6.68 GHz with 47.9% bandwidth, respectively.

• Physical Therapy Rehabilitation Science
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• 제5권1호
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• pp.15-21
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• 2016

Objective: The purpose of this study was to see the changes in muscle activity of the upper limb in persons using a smartphone. Design: Cross-sectional study. Methods: An experiment was conducted to target 15 right-handed university students. Experiments were carried out for students using cell phones for more than a year. In this study, experiments were carried out with one-handed and both handed operation of smartphone use in a sitting position, the same parameters with smartphone use in a standing position. The experiments were carried out by having the subjects write a text message in Korean on the smartphone for 3 minutes repeated 3 times with a rest period of 10 seconds given between each 3 minute period. Electromyography (EMG) was used to record the muscle activity of the upper trapezius (UT), extensor carpi radialis (ECR), and abductor pollicis (AP) during phone operation. Results: The muscle activity of the AP and ECR were significantly higher during single handed compared to double handed in both sitting and standing position (p<0.05). The muscle activity of the ECR was significantly higher in standing position compared to sitting position with double handed use of the smartphone (p<0.05). UT muscle activity of the right has been activated more than twice compared to the left UT in a sitting position (p<0.05). And UT muscle activity on the right has been activated more than five times compared to the left in a standing position (p<0.05). Conclusions: Using smartphone with double hand is useful for the prevention of musculoskeletal disorders.

• Physical Therapy Rehabilitation Science
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• 제7권3호
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• pp.119-126
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• 2018

Objective: The objective of this study was to describe the influence of smartphone usage on the upper limb muscles while in stable and unstable positions and during gait. Design: Cross-sectional study. Methods: The study was conducted with 20 right-handed university students between 20 and 27 years of age. Experiments were carried out on students who have used cell phones for more than a year. In this study, experiments were performed with one-handed and two-handed smartphone operations while on stable ground, and the same parameters were measured during smartphone use on unstable ground and during gait. Subjects were instructed to write a text message in Korean on the smartphone for 3 minutes. This was repeated 3 times, with a rest period of 10 seconds given between each 3-minute period. Electromyography was used to record the muscle activity of the upper trapezius, extensor carpi radialis, extensor pollicis longus, and abductor pollicis (AP) during phone operation. Results: The muscle activity value for the right AP in one-handed and the left-AP in two-handed operations was statistically higher than the other muscles in the stable position and during gait (p<0.0001). Also, the right AP in the one- handed operation condition was statistically higher than the two-handed condition (p<0.0001). Conclusions: The use of smartphones while in a stable position resulted in high muscle activity of the right upper limb AP. However, in an unstable position, there were no significant differences from the other muscle activities. Using smartphone while assuming various positions may lead to musculoskeletal disorders in different places.

• 한국전문물리치료학회지
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• 제26권2호
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• pp.24-33
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• 2019

Background: Spontaneous use of the upper extremities on the affected side of patients with stroke is a meaningful indicator of recovery and may vary by the age or dominant hand of patients. No prior study has reported changes in actual amount of use test (AAUT) and motor activity log (MAL)-28 according to age and handedness in healthy adults, and AAUT inter-rater reliability for assessment of healthy adults. Objects: This study aimed to (1) research the differences in AAUT and MAL-28 according to age and handedness in healthy adults, and (2) determine the inter-rater reliability of the AAUT. Methods: Seventy healthy adults participated in this study. The MAL-28 was assessed by dividing 61 subjects into young right-handed ($n_1=20$), young left-handed ($n_2=21$), and older right-handed ($n_3=20$) groups. The AAUT was assessed by dividing 63 subjects into young right-handed ($n_1=25$), young left-handed ($n_2=18$), and older right-handed ($n_3=20$) groups. Student's t-test and the Wilcoxon signedrank test were used for statistical analysis. Results: The Amount of Use (AOU) scale values for each group showed no significant differences between age groups and handedness groups in the MAL-28 (p>.05). The AAUT AOU scale value showed significant differences regarding dominant handedness in the AAUT (p<.05), but no significant differences according to age (p>.05). (2) Inter-rater reliability of the AAUT was excellent, except few items (item 9, 11, and 12). Conclusion: Although both the MAL-28 and the AAUT measured how much participants used their dominant arms in healthy subjects, the AAUT only showed significantly higher dominant arm use in left hander than the right hander. In addition, the inter-rater reliability of the AAUT was excellent. Current results can be utilized as a basic information when clinicians develop rehabilitation strategies, and AAUT was shown to be a reliable evaluation tool for measurement of upper extremity use in Korean adults, based on the reliability demonstrated by this study.

• 한국항행학회논문지
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• 제13권3호
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• pp.399-405
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• 2009

본 논문은 메타 재질 구조를 바탕으로 한 가변 감쇠기와 그 응용에 대하여 기술 하였다. 손실이 존재하는 전송선로를 이용한 감쇠기 단위 셀은 CRLH(Composite Right/Left Handed) 전송선로와 다이오드 바이어스 전압에 따라서 내부 저항값의 변화에 따라서 손실을 제어할 수 있는 PIN다이오드로 구성되어 있다. 또한, 내부의 초기 삽입 손실을 줄이기 위해서 두 개의 PIN 다이오드를 병렬로 연결하였다. 이 감쇠기는 감쇠기 단위 셀 숫자를 증가시킴으로서 감쇠량을 증가시킬 수 있는 주기적 구조로 설계되었다. 단위 셀의 전기적 특성은 주파수 1.5 GHz ~ 2.5 GHz에서 10dB의 감쇠량과 최대 15o의 위상변화를 확인하였다. 이러한 특성의 감쇠기를 직렬로 연결하여 벡터 변조기에 응용하였다.

• 한국전문물리치료학회지
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• 제14권4호
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• pp.91-98
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• 2007

In this study, 1,933 Korean male and female subjects ranging in age from 10 to 82 were selected to investigate the various statistics about hand dominance and employment characteristics of preferred hand in handling diverse products and facilities. The statistics show that 5.6% are left-handed and 7.6% are ambidextrous. The average left-hander has a strong tendency to use his or her left hand more often when taking a forceful action than one that requires accuracy. On the contrary, the average ambidextrous or right-handed person generally uses his or her right hand more with action that requires accuracy than force. Derived from such results, the conclusion is that depending on which hand is the dominant one, people seem to use their hands differently when they handle objects and is a point that should be considered in designing hand control devices.

• 한국항행학회논문지
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• 제21권1호
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• pp.84-89
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• 2017

본 논문은 CRLH (composite right/left handed) 전송선로 구조의 4중 모드 공진기를 이용하여 높은 대역간 격리도를 갖는 이중-광대역 대역통과 여파기를 설계하는 방법을 제안한다. CRLH 전송선로 구조를 해석하여 4중 모드 공진기의 s-패러미터와 공진 주파수를 유도하였다. 유도된 s-패러미터를 이용하여 새로운 구조의 이중-광대역 대역통과 여파기를 설계, 제작하였다. 측정 결과는 2.8-5.52 GHz, 9.68-12.26 GHz의 이중 통과대역에서 각각 1.08 dB, 2.01 dB의 삽입손실을 갖고, 6.34-8.42 GHz의 중간대역에서 38dB의 대역 격리도를 가져 설계 결과와 잘 일치하는 특성을 보여 주었다.