• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1918-1919
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• 2011

상체 지원 외골격 로봇은 크게 인간의 근력을 보조하는 형태와 인간의 근력을 증강하는 형태가 있다. 여기서는 인간의 근력을 증강하는 외골격 로봇을 중심으로 기술하고자 한다. 이러한 외골격 로봇은 팔의 EMG (Electromyograph;근전도) 신호를 측정하는 방법보다는 손의 힘을 직접 감지하는 방법을 통한 팔꿈치와 어깨의 엑추에이터를 구동하는 방식을 취하는 경향이 있다. 본 논문에서도 후자의 방식을 이용하여 손에 작용하는 힘을 분석하여 외골격 로봇을 움직이는 방식을 취하였다. 손의 힘 중에서도 인간을 중심으로 볼 때 위방향과 전진방향의 힘을 분석하기 위하여 2개의 F/T(Force/Torque) 센서를 사용하였으며 팔을 벌리는 동작은 엑추에이터 없이 자유롭게 동작이 가능하도록 설계하였다. 이러한 위방향 및 전진방향 힘의 크기를 팔꿈치와 어깨의 엑추에이터의 동작으로 바꾸어 인간의 동작을 도울 수 있고 힘을 증폭할 수 있는 외골격 로봇을 설계 제작하였다. F/T 센서는 손의 힘을 전기적 신호로 바꾸어주는 로드셀로 이루어지며 손의 힘을 최대한 잘 반영하기 위한 구조를 고안하였다. F/T 센서의 전기신호는 증폭기를 거쳐서 잡음을 제거한 후에 A/D 변환하여 processor에서 처리되어진다.

• Journal of Biomedical Engineering Research
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• v.24 no.5
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• pp.443-446
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• 2003

In the present study. the design of multi-axial lower extremity orthosis was presented with adduction and abduction force data which were measured from three children with cerebral palsy and a normal child. The measurements of adduction and abduction forces were conducted in standing and wolking condition. Adduction and abduction forces were measured by strain gages which were attached on the lateral uprights of lower extremity orthoses. In the standing condition. addcution force of childrens was distributed from 0.11 kgf to 0.26 kgf. During the walking condition. adduction force was reached to 1.56 kgf and abduction force was reached to 1.52 kgf.

• Journal of the Institute of Electronics and Information Engineers
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• v.54 no.2
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• pp.146-150
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• 2017

In OFDM system, the out-of-band radiation of ensemble interferes with the adjacent ensemble and result in the reduction of receiving performance. So the reduction scheme of out-of-band radiation is very important. In this paper, a time-domain windowing method to reduce the out-of-band radiation is considered to DAB systems. We adopt the considered method to T-DMB(DAB mode-1) and AT-DMB Systems, and we get about 3-dB gains of out-of-band radiation. And also we show that the considered method doesn't reduce the BER performance.

• Journal of the Korean Institute of Gas
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• v.2 no.1
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• pp.83-89
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• 1998

Experiments had been conducted Qualitatively regarding flow measurement errors of orifice flowmeter due to temperature difference between the inside and outside the natural gas meter-run in case of no pipe insulations. The primary factors considered in this study are fluid velocity and surrounding temperature. In addition, a portion of thermal radiation due to the sun was involved as a factor. The results showed that the considerable errors were not detected even in conditions of low flow rates and large temperature difference between the inside and outside the meter-run.

• Clinical and Experimental Reproductive Medicine
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• v.36 no.2
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• pp.129-136
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• 2009

The incidence of ectopic pregnancy is increased since in vitro fertilization-embryo transfer (IVF-ET) has started. And because of the possibility of combined pregnancy after IVF-ET, bilateral adnexal area and other portion of pelvis should be examined carefully by transvaginal ultrasonography during follow-up period. The rate of combined pregnancy after IVF is estimated to be as high as 0.2~1%. Since the incidence of combined pregnancies is markedly higher with IVF, special attention to this possibility after ET is warranted. According to a recent report, the occurrence of interstitial pregnancy is estimated to be 1:3600 for all pregnancies achieved with IVF. The prevalence of interstitial pregnancies is 2~4% of ectopic pregnancies. Interstitial pregnancies tend to be diagnosed later than most other ectopic pregnancies, and if uterine rupture occurs, the resulting hemorrhage can be severe. Currently, about 2% to 3% of interstitial pregnancies are thought to carry a maternal death, which is twice that of other tubal gestations. We report a case of simultaneous left tubal and right interstitial pregnancies after IVF-ET with a brief review of literature.

• Progress in Medical Physics
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• v.17 no.4
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• pp.238-245
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• 2006

To assess the ability of an extravasation defection accessory (EDA) to detect the clinically important extravascular Injection of iodinated contrast material that was delivered with an automated mechanical power injector. The purpose of this study was to assess the ability of this device during clinically important episodes of extravasation. The EDA system was composed of a strain gage, an amplifier and a computer-based system. In the rabbit experimental cases, there were seven true-positive cases (range of the extravasation volumes: $14{\sim}23 ml$). The algorithm results showed seven true-positive cases (range of the extravasation volumes: $7{\sim}16ml$), nineteen true-negative cases, two false-positive cases and no false-negative cases. The EDA system had a sensitivity of 100% and a specificity of 90% for the detection of clinically important extravasation. The EDA system had good sensitivity for the detection of clinically important extravasation and the EDA system has the clinical potential for the early detection of extravasation of the contrast medium that is administered with power injectors.

• Journal of the Korea Concrete Institute
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• v.17 no.4 s.88
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• pp.551-558
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• 2005

The setting and hardening of concrete is accompanied with nonlinear temperature distribution caused by development of hydration heat of cement. Especially at early ages, this nonlinear distribution has a large influence on the crack evolution. As a result, in order to predict the exact temperature history in concrete structures it is required to examine thermal properties of concrete. In this study, the convection heat transfer coefficient which presents thermal transfer between surface of concrete and air, was experimentally investigated with variables such as velocity of wind, curing condition and ambient temperature. At initial stage, the convection heat transfer coefficient is overestimated by the evaporation quantity. So it is essential to modify the thermal equilibrium considered with the boiling effect. From experimental results, the convection heat transfer coefficient was calculated using equations of thermal equilibrium. Finally, the prediction model for equivalent convection heat transfer coefficient including effects of velocity of wind, curing condition, ambient temperature and boiling effects was theoretically proposed. The convection heat transfer coefficient in the proposed model increases with velocity of wind, and its dependance on wind velocity is varied with curing condition. This tendency is due to a combined heat transfer system of conduction through form and convection to air. From comparison with experimental results, the convection heat transfer coefficient by this model was well agreed with those by experimental results.

• Korean Journal of Cognitive Science
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• v.15 no.1
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• pp.43-67
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• 2004

Using qualitative research methodology, this study has investigated the semantic features of 39 nouns, which are classified into the categories of grains, fruits and vegetables. A survey has been conducted with a substantial number of undergraduate students, who were asked to describe any semantic features they associated with the lexical items within the three categories. The analysis of the survey data shows that the concepts of examples of fruits are defined predominantly by intrinsic semantic features, while those of grains and vegetables are defined noticeably by extrinsic semantic features rather than intrinsic ones. Intrinsic semantic features are any properties inherent in an object itself and extrinsic semantic features are defined as any properties constructed by association with other objects or personal experiences in a certain situation. However, this study does not maintain that either intrinsic or extrinsic semantic features solely define the concepts of the examples of the three categories. Instead, it concludes that both kinds of semantic features are involved in the representation of the concepts of those vocabularies, with intrinsic features salient in the category of fruits and extrinsic features salient in the categories of gains and vegetables.

• Journal of the Korea Institute of Building Construction
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• v.16 no.5
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• pp.397-403
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• 2016

As a building energy saving standard strengthened, The number of building installed external thermal insulation composite system(ETICS) using EPS insulation increased. But frequent fire accident in the buildings installed EIFS using EPS led to strengthening of building fire safety regulation. This study is for fire property of EPS ETICS reinforced with noncombustible calcium silicate-based mineral insulation as a fire spread prevention structure(FSPS). Fire test for large scale wall by ISO 13785-2 was applied and results showed EPS EIFS with FSPS got 3~8 times superior fire safety than normal EIFS by visual investigation. Temperature and heat flux measurement results, which data of upside of specimen were lower than downside, also supported fire safety of EIFS with FSPS.

• Journal of Digital Convergence
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• v.16 no.7
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• pp.441-449
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• 2018

The aims of this study were to consist of the eccentric viewing training software based on Korean and to examine the effects on reading speed. The program was used the Korean stimuli by rapid serial visual presentation. Single-subject A-B-A' research design for 2 normally-sighted young adults was used to examine the effect. The reading speed data on short-sentence of participants showed a statistically significant result, as both data from the intervention period and post-training baseline period deviated more than 2 standard deviations from the pre-training baseline period. Through this study, we suggested that eccentric viewing training software based on Korean characters stimulation would allow clinician in Korea to improve reading skills of low vision individuals with central scotomas.