• 한국재난정보학회 논문집
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• 제8권2호
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• pp.188-196
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• 2012

고유진동수와 같은 동적파라미터는 구조물 전체의 강성에 대한 정보를 제공할 수 있어 격납건물과 같은 대형구조물의 건전성 모니터링에 유용하게 사용될 수 있다. 이러한 동적특성을 구조물의 사용성에 지장을 주지 않고 추출하기 위해서는 상시진동을 이용한 모달해석 기법의 적용이 필수적이다. 이 연구에서는 상시진동 측정자료를 이용하여 월성 2호기 격납건물의 동적파라미터를 산정하였다. 연구의 가능성은 격납건물의 수치해석모델을 이용하여 검증하였다. 월성 2호기 격납건물에서 측정된 상시진동에 대한 모달해석 결과 해석모드와 충분한 상관성을 갖는 동적파라미터를 산정할 수 있었다.

• 한국실내디자인학회논문집
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• 제25권2호
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• pp.30-40
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• 2016

This study analyzed the attention concentration tendencies of one(1) subject who showed convergent exploratory acts actively through the gaze-brainwave measurement experiment of cafe space images and our research findings are as follows. First, the areas of interest (AOIs) that the subject gazed visually by paying attention to it and concentrating on it at a cafe space include counter&menu area, sign area, partition area, image wall area, stairs area, and movable furniture area, and built-in furniture area: seven areas in total. Second, conscious gaze frequency appeared the highest in counter&menu area, and conscious gaze appeared more later than in initial times. Third, conscious gaze pattern was divided into the zone that explored various areas dispersely (distributed exploratory zone) and the zone that explored between particular areas concentratedly (intensive exploratory zone). Fourth, as a result of analyzing the brainwave attention concentration, it was found that the attention concentration in prefrontal lobe (Fp1, Fp2) and frontal lobe (F3, F4) rose to a higher level in the zone of 15 to 16 seconds and this time zone was considered to be a zone where gazing at counter&menu area was very active. In addition, the attention concentration appeared higher in the initial zone than in the later zone, among the entire experimental time zones. Finally, as a result of analyzing the changes in activation by brain portion of the SMR wave expressed when maintaining the arousal and attention concentration, it was found that the right prefrontal lobe and the frontal lobe became activated in the time zone when the intensive exploration of "counter&menu area" and "movable furniture${\leftrightarrow}$built-in furniture area" had occurred and the time zone when the intensive exploration of "image wall${\leftrightarrow}$partition area" and "counter&menu${\leftrightarrow}$sign area" had occurred.

• 한국산학기술학회논문지
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• 제17권5호
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• pp.269-274
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• 2016

본 연구는 호퍼와 같은 공정에서 필연적으로 발생하는 스케일 또는 막힘 현상을 방지하기 위해 적용할 수 있는 저주파 전자해머 구동 시스템의 개발에 관한 것이다. 전자기계식 hammering 구동 방식은 진동과 충격량을 동시에 발생시키는 방식으로, 본 논문에서는 전자해머의 특성을 고찰하기 위하여 전자해머에 장착된 직/병렬 스프링 상수 해석을 하였고 발생에너지는 E코어에 부착된 스프링 상수가 모두 같을 경우에 계산된 등가 스프링 상수와 E코어와 I코어 사이의 동작 변위의 곱으로 계산할 수 있음을 보였다. 또한 전자해머의 충격량을 최대화하기 위하여 맥동파 구동 알고리즘을 적용하였으며, 이 알고리즘은 논리 AND 연산과 마이크로 콘트롤러(atmega128)의 타이머 인터럽트와 PWM 기능을 사용하여 구현하였다. 전자해머의 구동회로는 IGBT로 구성된 H-브리지 방식으로 설계하였고, 가속도계 측정법으로 개발한 전자 해머 시스템의 성능을 검증하였다. 실험 결과 제안한 시스템이 기계적 에너지를 양호하게 발생시킬 수 있으며, 호퍼와 같은 공정에 적용할 수 있음을 보였다.

• 한국산학기술학회논문지
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• 제10권7호
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• pp.1536-1541
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• 2009

본 논문은 2단 스태거 펄스열을 사용하는 레이더 신호를 분리하는 전자전 장비의 알고리즘에 관한 연구이다. 일반적으로 레이더는 고정된 펄스열을 사용하였으나 최신 레이더들은 전자보호 기능을 강화하기 위해서 펄스열을 바꾸고 있다. 2단 스태거 펄스신호는 2가지의 펄스반복주기를 교대로 사용하여 레이더의 탐지 성능을 향상시키고 전자보호 능력을 향상시키는 좋은 방법이다. 종래에는 히스토그램 방법을 사용하여 스태거 신호를 식별하였으나, 본 논문에서는 펄스열의 2차 차분을 이용하는 방법으로 신호를 식별하였으며, 종래에 사용하던 방법과 비교해서 처리 속도가 매우 빠르다. 제안된 알고리즘은 2단 스태거 펄스열을 포함한 각종 펄스열을 분리하는 특성이 매우 양호하였다.

• 한국진공학회지
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• 제22권4호
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• pp.175-180
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• 2013

본 연구에서는 반도체 소자 생산 공정 중 발생하는 오염입자에 의해 실시간 오염입자 측정장치인 In-Situ Particle Monitor(ISPM)의 광학창의 오염을 방지하기 위한 모듈 개발에 관한 연구이다. 개발한 광학창 오염방지 모듈은 실시간으로 측정하는 ISPM 내 광학창 표면에 오염입자가 흡착되는 것을 방지하기 위한 장치로 적합한 초음파 모듈 개발이 성공적 연구의 핵심내용이다. 또한 그 효과를 극대화하기 위한 구조적인 최적화도 필요하지만 초음파 힘의 표면 전달효율 향상 기술도 개발이 필요한 핵심 기술이다. 개발된 광학창 오염방지 모듈이 장착된 ISPM은 양산용 증착공정 장비(BPSG 증착장비) 배기구에 설치되었으며, 공정조건 별 오염방지 모듈의 성능과 더불어 ISPM 측정 효율도 함께 검증하였다.

• 대한물리의학회지
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• 제3권3호
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• pp.185-192
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• 2008

Purpose : The purpose of this study is to examine the effect of the electro-acupuncture stimulation into the multifidus for the lumbar flexibility improvement and pain reduction. The subjects were consisted of 20 women patients with chronic low back pain. Methods : 20 women patients with chronic low back pain voluntary participated for the research. 15 minute electro-acupuncture stimulation(frequency: 4Hz, Intensity: below threshold of pain) with Infra-red therapy, 3 times a week during 6 weeks period. Acupuncture application given to the patients' trigger point of the multifidus. The Application of multifidus was L3, L4, L5 spinal vertebra levels Short form McGill pain questionnaire (SFMPQ) was used to measure patient's pain level. Lumbar flexibility measurement was trunk flexion and trunk extension. Global Perceived Effect Scale(GPES) was used to measure recovery or worse of patient's condition. Results : SFMPQ was after treatment showed significantly decreased more than before stimulation treatment (P<.05). Lumbar flexibility was after treatment showed significantly increase more than before treatment(P<.05). GPES was after treatment showed significantly increased more than before treatment(p<.05). Conclusion : This study will be used as treatment method of patient with chronic LBP. The multifidus muscle in chronic LBP patients clinical significance. Most of chronic LBP patients have multifidus contraction pattern. So chronic LBP patients necessary multifidus muscle release treatment.

• 비파괴검사학회지
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• 제23권3호
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• pp.254-262
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• 2003

본 연구는 목재(참나무 판목 판재) 건조 중 발생하는 음향방출 신호에 대하여 목재 내 수분이동에 의한 신호와 표면할열에 의한 신호를 해석하고 분류하기 위하여 수행되었다. AE 신호의 특징값들에 대한 상관분석을 실시하여 상호의존성이 높은 변수를 제거한 후 주성분 분석을 실시하였다. AE 변수들을 독립변수로 한 분류기와 주성분들을 독립변수로 한 분류기에 대하여 분류성능을 비교하였다. 목재 건조 시 발생하는 표면할열과 수분이동에 따른 AE 신호 파형을 분석한 결과 대체적으로 표면할열에 의한 신호가 최대진폭이 크며 상승시간이 팎고 상대적으로 고주파의 신호인 것으로 분석되었다. 다중 회귀분석모델을 이용하여 수분이동에 의한 신호와 표면할열에 의한 신호를 분류할 수 있는 분류기를 개발하고 평가한 결과 개별 AE 변수들을 독립변수로 하는 분류기 보다 주성분들을 독립변수로 하는 분류기의 분류성능이 양호한 것으로 나타났다.

• Food Science and Biotechnology
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• 제17권4호
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• pp.705-712
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• 2008

Sweet potato starch was modified using Thermus aquaticus $\alpha$-1,4-glucanotransferase ($Ta{\alpha}GT$), and its structural and rheological properties were investigated. $Ta{\alpha}GT$-modified starch had a lower amylose level and molecular weight than raw starch. The chain length distribution showed an increased number of short and long branched chains and the formation of cycloamyloses. Compared with raw starch, $Ta{\alpha}GT$-modified starch displayed a lower gelatinization enthalpy and a wider melting temperature range. The X-ray diffraction of $Ta{\alpha}GT$-modified starch was a weak V-type pattern with distinct sharp peaks at 13 and $20^{\circ}$. Scanning electron micrographs of modified starch exhibited big holes on the surface and the loss of granular structure. The frequency sweep measurement revealed that the gel of $Ta{\alpha}GT$-modified starch was more rigid than raw starch gel. However, the structure of modified starch gel was destroyed by heating at $75^{\circ}C$, and a firm gel was re-formed by subsequent storage at $5^{\circ}C$, indicating thermoreversible property.

• 대한지역사회영양학회지
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• 제8권1호
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• pp.3-14
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• 2003

The purpose of this study was to estimate the nutrient intake, dietary habits, and body indices among preschool children. The study subjects were 166 kindergarten children, aged 4 to 6 years. A measurement of the weight, height, chest circumference, and head circumference of the children was conducted. The general home environment and factors related to the eating habits of children were collected using a questionnaire that included information about physical activity, outdoor playing time, television watching, family income, and parents education and occupations. Underweight, overweight were defined based on a value of less than 110 and more than 140 on the Rohrer Index, or less than 90 and more than 120 on the weight-length index (WLI). The average Rohrer and WLI for the preschool children were 14.3 $\pm$ 23.2% and 104 $\pm$ 13.5%. Using the WLI, 12.7% of the preschool children were underweight 62.6% were normal, and 24.7% were overweight or obese. On the Rohrer Index, 32.0% of the preschool children were underweight, 34.7% were normal, and 34.1% were overweight or obese. With regard to frequency of regularity of eating breakfast, 2.5% of preschool children skipped breakfast every morning. The risk of being overweight increased in preschool children who had faster eating times. The Rohrer and WLI were negatively related to faster eating times. The average daily energy intake was 1272 Kcal, which corresponded to 79.5% of the Korean RDA. In particular, the average intakes of calcium, iron, and vitamin B$_2$ were much lower than the Korean RDAs for each of those nutrients. Children whose mothers had occupations were at greater risk of decreased nutrient intake than those whose mothers were at home. The data presented in this study confirm that, in preschool children, undernutrition remains the nutritional problem of great concern in Korea, even though Koreans are starting to have worrisome rates of overweight. Therefore, during the early years of life, focus should remain on sustaining Proper growth and development.

• 임상간호연구
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• 제26권1호
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• pp.59-74
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• 2020

Purpose: The purpose of this study is to investigate new nurses' needs for intravenous infusion therapy training by analyzing the current training status. Methods: This study examined the needs for intravenous infusion therapy training with 159 new nurses. The measurement tool consisted of 93 items developed based on intravenous therapy-related studies, and was evaluated on a 4-point Likert scale. For data analysis, SPSS/WIN 25.0 was used, and frequency, percentage, average, standard deviation, paired t-test, were performed. Results: The demand for intravenous therapy education was analyzed using a questionnaire composed of 8 areas, 16 sub-areas, and 93 items. According to the findings, post-ward placement intravenous therapy education(83.7%) is conducted more often than in preliminary education (72.2%). The demand for intravenous infusion therapy education did not differ significantly in preliminary and post-ward placement education (t=-.89, p=.376). While therapy skills were preferred in preliminary education, there were high demands for education content related to blood transfusion, central venous catheter, and drug use in continuing education. As for preferred teaching methods, lecture (38.2%) and simulation (26.7%) were most answered for preliminary education, while a range of methods were preferred for continuing education including lecture (31.1%), clinical practice (20.6%), preceptor training (19.8%), simulation (16.8%), and self-study (11.6%). Conclusion: For efficient training, it is required to provide different education contents and methods for each stage.