• Journal of international Conference on Electrical Machines and Systems
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• 제2권2호
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• pp.179-183
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• 2013

This paper report on experimental results of 5-level inverter by DC divided link voltage. We have alreday reported that DC divided link valtage comes to be able to reduse harmonic of out line voltage. So we tested whether DC divided link voltage can reduce harmonics in experimental setup. This paper shows simulation results and experimental results. And we confirmed that DC divided link voltage can also apply in experimental setup.

• 한국콘텐츠학회논문지
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• 제20권8호
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• pp.397-407
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• 2020

본 연구는 한국과 중국 청소년들의 기본심리욕구와 주관적 웰빙 간의 관계에서 투지의 매개효과를 분석하기 위해 수행하였다. 연구대상자는 한국과 중국 청소년 각각 150명씩 총 300명이었다. 연구결과, 첫째, 한국 청소년들은 기본심리욕구의 자율성이 유의하게 높았고, 중국 청소년들은 유능성이 유의하게 높게 나타났다. 둘째, 기본심리욕구와 투지 및 주관적 웰빙 간에 유의한 정적 상관관계가 있었다. 셋째, 기본심리욕구가 주관적 웰빙에 미치는 직접효과는 한국 청소년들이 중국 청소년들보다 더 강한 것으로 나타났다. 넷째, 기본심리욕구가 투지를 통해 주관적 웰빙에 미치는 간접효과는 통계적으로 유의하게 나타났다. 다섯째, 투지의 매개효과는 중국 청소년들이 한국 청소년들보다 더 강한 것으로 나타났다. 이러한 연구결과를 중심으로 청소년들의 주관적 웰빙을 증진시키기 위한 투지의 중요성을 논의하고, 한국 청소년들의 유능성 증진과 중국 청소년들의 자율성 증진을 위한 접근 방향에 대해 논의하였다.

• 한국수학교육학회지시리즈E:수학교육논문집
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• 제27권1호
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• pp.19-37
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• 2013

P대학에서는 수학 기초학력 부진학생들의 문제해결력 향상과 학업성취도 고양을 위하여, 기초수학및연습 교과목을 개설하고 있다. 이 교과목은 미적분학의 선수과목으로 운영되며, 수준별 학급을 편성하여 다양한 학습 자료를 활용한 발표 중심의 수업을 진행하고 있다. 본 논문에서는 한국공학인증 지원을 위해 기초수학및연습 교과목의 강의 포트폴리오를 제출한 30개 학급에서 수강한 1,106명의 취득 성적과 및 강의평가 결과를 분석하였다. 아울러, 각 담당교수가 제출한 강의 포트폴리오의 강의개선 보고서를 기반으로 기초수학및연습 교과목의 수준별 학급 운영에 대한 유의점과 그 개선방안을 찾아본다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2010년도 제39회 하계학술대회 초록집
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• pp.63-63
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• 2010

Using both experimental and theoretical approaches, we have investigated the adsorption properties of an organic molecule (HATCN), which is used in OLEDs as an efficient hole injection layer, on metal and inert surfaces. We have also studied the structural and electronic properties of such interfaces and the dependences on deposition thickness. We have observed different trends in work function changes with different surfaces. Our photoelectron spectroscopic measurements have revealed an abnormal phenomenon in HATCN on a metal (Cu) surface: the work function decreases at lower coverage (~monolayer) of HATCN on a metal (Cu) surface, but it increases back and becomes higher than that of a bare Cu surface at higher coverage. It has, on the contrary, been observed that the work function of graphene surface just increases as the HATCN coverage increases. Our first-principles density functional calculations has not only verified our experimental observations, but also disclosed the underlying mechanism of such abnormal and different work function behaviors. We have found that the change in work function results from mutual polarization induced by the geometrical deformation and the bond dipole formed at the interface due to the charge redistribution. At low coverage of HAT-CN on Cu substrate, the former reduces the work function significantly by pulling down the vacuum level, while the latter tends to push up the vacuum level resulting in the work function increase.

• Asian Pacific Journal of Cancer Prevention
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• 제15권19호
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• pp.8489-8493
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• 2014

Objective: To verify the basic preoperative evaluation in the discrimination between benign and malignant adnexal masses in our clinical practice. Materials and Methods: Data were collected on the records of 636 women with adnexal masses who had undergone surgery either by open or endoscopic approaches. Those with obvious signs of malignancy, any history of cancer, emergency surgeries without basic evaluation were excluded. The preoperative features by age, ultrasound and serum Ca125 level were compared with final histopathological diagnosis at the four departments of the institution. These are the general gynecology (Group 1: exploratory laparotomy), the gynecologic endoscopy (Group 2: laparoscopy and adnexectomy), the gynecological oncology (Group 3: staging laparotomy) and the gynecologic endocrinology and infertility (Group 4: laparoscopy and cystectomy). Results: There were simple and complex cyst rates of 22.3% and 77.2%, respectively. There were 86.3% benign, 4.1% (n:20) borderline ovarian tumor (BOT) and 6.4% (n:48) malignant lesions. There were 3 BOT and 9 ovarian cancers in Group 1 and one BOT and two ovarian cancer in the Group 2. During the surgery, 15 BOT (75%) and 37 ovarian cancer (77%) were detected in the Group 3, only one BOT was encountered in the Group 4. The risk of rate of unsuspected borderline or focally invasive ovarian cancer significantly increased by age, size, complex morphology and Ca125 (95% CI, OR=2.72, OR=6.60, OR=6.66 and OR=4.69, respectively). Conclusions: Basic preoperative evaluation by comprehensive ultrasound imaging combined with age and Ca125 level has proved highly accurate for prediction of unexpected malignancies. Neither novel markers nor new imaging techniques provide better information that allow clinicians to assess the feasibility of the planned surgery; consequently, the risk of inadvertent cyst rupture during laparoscopy may be significantly decreased in selected cases.

• 대한지리학회지
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• 제37권3호
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• pp.276-291
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• 2002

현행 교육과정의 지리교육내용은 포괄적이고 추상적으로 제시되고 있다. 또한 전체 교육의 일부분으로 설정되기 때문에, 지리교육 자체의 교육 내용 체계화를 이루기 어렵다. 본 연구에서는 현행 교육과정을 보완하고 지리교육 내용을 체계화하는 방법으로, 지리학에 기반을 둔 지리교육 내용의 표준 설정 방법을 제안한다. 지리교육의 표준 설정 방안으로 대주제, 기본 주제, 주요 표준, 표준, 상세 표준을 제시하였다. 대주제는 지리교육 전반을 통찰하는 대개념으로서 '인간과 환경의 상호작용 이해', '장소 또는 지역에 대한 이해', '인간과 장소의 상호작용 이해'의 3개를 선정하였다. 기본 주제는 '지리적 기능', '자연 환경' '인문 환경', '장소 및 지역', '인간과 장소의 상호작용'의 5개를 선정하였다. 표준은 구체적이고 측정 가능한 지리교육내용을 제시하는 단계로서 '주요 표준'표준', '상세 표준'의 3단계로 상세화했다.

• 한국가금학회지
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• 제21권4호
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• pp.249-256
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• 1994

This study was conducted to investigate the effects of the addition of varied levels of NaCI and phosphates to the breast meat of spent layers(2 \pm 0.2 kg), which were stabilized for over 24 h before slaughter, on the protein extractability, thiobarbituric acid(TBA) and volatile basic nitrogen (VBN). Within 1 h after slaughter, breast meat was removed and treated with NaCI(0, 1, 2, 3%) and phosphates(0.25% and 0.5%) using a hot-salted method. The breast meat samples were stored at 4\pm$1^{\circ}C$ for 3 d. The results obtained were summarized as follows. 1. Soluble protein contents of salt-treated groups were significantly higher than that of control (P<0.05) and showed a positive relationship with the levels of salt. At a constant level of NaCI, the soluble protein content was proportionately elevated by the levels of phosphates (P<0.05). It decreased significantly in both control and salt-treated groups during storage (P<0.05). 2. TBA values of salt-treated groups were significantly higher than that of control(P<0.05) and showed a positive relationship with the levels of salt. At a constant level of NaCI, TBA values in 0.5% phosphates treatment groups were significantly lower than that in 0.25%(P<0.05). It increased significantly in both control and salt-treated groups during storage(P<0.05). 3. VBN values of salt-treated groups were significantly lower than that of control(P<0.05) They increased significantly by the salt treatment for the first day of storage(P<0.05), but not from the second day of storage. VBN values in both control and salt-treated groups were significantly increased during storage(P<0.05). After the first day of storage and at the same level of NaCI, no significant difference in VBN value was observed between the two levels of phosphates.

• 기술혁신학회지
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• 제4권2호
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• pp.127-142
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• 2001

This paper presents an econometric model for measuring basic research capacity index(BRCI) of each OECD countries and analyses the gap in terms of time lag measured and forecasted in connection with factor analysis and BRCI progress function. Based on the analysis, gross domestic expenditure on R&D(GERD), total R&D personnel higher education expenditure on R&D(HERD) and number of science and technical papers based on SCI are more effective than other factors to BRCI. Also, BRCI progress function shows that 29 years is needed for Korea to catch up the level of German's BRCI of year 1998. But, it's impossible for Korea to catch up US and Japan. Therefore, with restricted scientific resources, Korea's own strategy for strengthening basic research capacity is going to be more important in 21st century.

• 한국기술혁신학회:학술대회논문집
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• 한국기술혁신학회 2001년도 춘계학술대회:발표자료
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• pp.473-492
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• 2001

This paper presents an econometric model for measuring basic research capacity index(BRCI) of each OECD countries and analyses the gap in terms of time lag measured and forecasted in connection with factor analysis and BRCI progress function. Based on the analysis, gross domestic expenditure on R&D(GERD), total R&D personnel, higher education expenditure on R&D(HERD) and number of science and technical papers based on SCI are more effective than other factors to BRCI. Also, BRCI progress function shows that 29 years is needed for Korea to catch up the level of German's BRCI of year 1998. But, it's impossible for Korea to catch up US and Japan. Therefore, with restricted scientific resources, Korea's own strategy for strengthening basic research capacity is going to be more important in 21st century.

• 전자공학회논문지A
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• 제30A권12호
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• pp.117-124
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• 1993

In this paper we propose a new thchnology mapping algorithm for multiplexer-based FPGA's The algorithm consists of three phases` First, it converts the logic functions and the basic logic mocule into BDD's. Second. it covers the logic function with the basic logic modules. Lastly, it reduces the number of basic logic modules used to implement the logic function after going through cell merging procedure. The binate selection is employed to determine the order of input variables of the logic function to constructs the balanced BDD with low level. That enables us to constructs the circuit that has small size and delay time. Technology mapping algorithm of previous work used one basic logic module to implement a two-input or three-input function in logic functions. The algorithm proposed here merges almost all pairs of two-input and three-input functions that occupy one basic logic module. and improves the mapping results. We show the effectiveness of the algorithm by comparing the results of our experiments with those of previous systems.