• Applied Microscopy
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• 제49권
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• pp.3.1-3.7
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• 2019

Graphene, which is one of the most promising materials for its state-of-the-art applications, has received extensive attention because of its superior mechanical properties. However, there is little experimental evidence related to the mechanical properties of graphene at the atomic level because of the challenges associated with transferring atomically-thin two-dimensional (2D) materials onto microelectromechanical systems (MEMS) devices. In this study, we show successful dry transfer with a gel material of a stable, clean, and free-standing exfoliated graphene film onto a push-to-pull (PTP) device, which is a MEMS device used for uniaxial tensile testing in in situ transmission electron microscopy (TEM). Through the results of optical microscopy, Raman spectroscopy, and TEM, we demonstrate high quality exfoliated graphene on the PTP device. Finally, the stress-strain results corresponding to propagating cracks in folded graphene were simultaneously obtained during the tensile tests in TEM. The zigzag and armchair edges of graphene confirmed that the fracture occurred in association with the hexagonal lattice structure of graphene while the tensile testing. In the wake of the results, we envision the dedicated preparation and in situ TEM tensile experiments advance the understanding of the relationship between the mechanical properties and structural characteristics of 2D materials.

• 한국생산제조학회지
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• 제23권3호
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• pp.310-317
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• 2014

The Next-generation High-speed Rail Technology Development Project was started in 2007 by the Korean Government with the aim of developing the core technologies for a high-speed electric multiple unit (EMU) railway system. This is the first attempt to develop a high-speed EMU railway. High-speed EMU trains have superior acceleration and deceleration compared to push-pull high-speed railways such as KTX(Korean Train eXpress). A prototype train was developed and tested on a high-speed line starting in 2012. The new train must maintain running safety during the test. Generally, the international standard (UIC518) is adopted to evaluate the running safety of trains. This method suggests that the test zone must have over 25 sections, and the length of each section must be 500 m. However, it is difficult to implement these test conditions for a real high-speed line. In this study, we analyzed the running safety using several test section lengths (100 m to 500 m) and compared the results. The results of this study will be used to establish a running safety evaluation method for high-speed EMU railways.

• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1997년도 추계학술대회
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• pp.411-414
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• 1997

This paper describes the design guideline, methodology and general specification of the developed 12 channel interpretive electrocardiograph. The developed 12 channel electrocardiograph consists of main module, patient module, DSP module, interface module, power/battery module, TFT color LCD and thermal recorder. The control panel of the system has full keyboard, rotate/push button, function key and unctional indicators. The graphic user interface program conveniently allows user to record, setup, store, manage ECGs. A variety of system configurations give it ability to make user favorable environment. This system also has a resting adult's ECG analysis program. The developed system and program will be continusely evolved using a database of clinically correlated ECGs.

• 기술혁신연구
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• 제13권2호
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• pp.97-131
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• 2005

This paper has discussed several issues regarding the barriers and opportunities for technological catch-up by the late-comer countries and firms. As one of the barriers to technological catch-up, the paper emphasizes the uncertainty involved with the third stage of learning how to design. The barriers arise because as the forerunner firms refuse to sell or give license to successful catching-up firms who thus have to design the product by themselves. The paper discusses how to overcome this barrier. It also notes that if the crisis of design technology is a push factor for leapfrogging, arrival of new techno-economic paradigm can serve as a pull factor for leapfrogging, serving as a winder of opportunity. The, it emphasized the two risks with leapfrogging, namely the risk of choosing right technology or standards and the risk of creating initial markets, and how to overcome these risks. It discusses how to overcome these risks in leapfrogging, and differentiates diverse forms of knowledge accesses. Then, the paper takes up the issue of whether there can be a single common or several models for catch-up. A common element of catching-up is to enter new markets segments quickly, to manufacture with high levels of engineering excellence, and to be first-to-market by means of the best integrative designs. This observation is supported by the fact that Korea and Taiwan has achieved higher levels of technological capabilities in such sectors as featured by short cycle time of technology. The possibility of two alternative models for catch-up is also discussed in terms of the key difference between Korean and Taiwan, especially in the position toward the source of foreign knowledge and the paths taken toward the final goal of OBM. Taiwan followed the sequential steps of OEM, ODM and OBN, in collaboration or integration with the MNCs. Korean chaebols jumped from OEM directly to OBM even without consolidating design technology.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.1203-1208
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• 2007

In the past decades, complain about ground vibration and noise induced by pile driving has been quickly increased. Because of that, auger drilled piling methods have frequently used specially in urban area. However, the present auger drilled piling methods induce inevitable ground disturbance as well as a certain degree of vibration and noise due to the final hammering. For these reasons, a new auger drilled piling method is required to be developed. This paper introduces PDT(Pulse Discharge Technology) piling method and presents the characteristics of bearing capacity. The PDT piling method is to install in-situ piles using electric power so called Pulse. The pile installed by PDT appears to be able to develop shaft and end bearing capacity efficiently. This paper introduces PDT(Pulse Discharge Technology) piling method, which is the 512nd new construction technology. The PDT piling method is to install in-situ piles using electrical power so called Pulse power. The pulse power is physical value that indicates the energy change per unit time(dE/dt). Since the pulse power is to push ground, using the pulse power is enable a hole to be expanded as well as the ground to be improved by compaction. Therefore, The pile installed by PDT appears to be able to develop shaft and end bearing capacity efficiently. In this study, couples of pile loading tests were carried out to figure out whether or not the PDT piling method is applicable to constructions like rail road facility. As a result, it was concluded that the PDT piling technique meet the requirements for such a rail road related construction.

• 대한통합의학회지
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• 제3권1호
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• pp.81-90
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• 2015

Purpose: The purpose of this study was to investigate any visible difference in shoulder stability muscle activity along the bending angle($70^{\circ}$, $90^{\circ}$, $110^{\circ}$) to perform the open kinetic chain(OKC) and closed kinetic chain(CKC) exercise. Method: This study was performed on normal 20 males subjects. Exercise was carried out in two ways OKC and CKC. Shoulder stability muscles are examined activity in the bending angles. In the OKC and CKC exercise to subjects with stretched out waist straightened, and than push forward the shoulder. Muscular activation was examined using the WEMG-8. Result: The results of this study were as follows. 1. Only in the trapezius muscle, it showed specific interaction between exercise methods and angles. When it comes to muscle activity, there was no significant difference in all muscles except for the anterior fibers of the deltoid muscle during both CKC and OKC exercise. 2. The average value of maximum muscle activity was significantly increased with increasing order of angles. But in CKC exercise, the muscle activity of infraspinatus tended to decrease with increasing angles. Conclusion: To summarize the research results, the muscle activity in upper fibers of the trapezius, anterior fibers of the deltoid, and serratus anterior was significantly different depending on the angle of the shoulder in both CKC and OKC exercise.

• 기술혁신연구
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• 제7권1호
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• pp.14-35
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• 1999

This paper presents the relationship between the pace of structural change and the magnitude of employment growth in the manufacturing sector in OECD countries. To measure the pace of structural change, the compositional change index in value-added in manufacturing sector is introduced. For mid to long-term there seems to be a positive relationship between the pace of structural change and the magnitude of employment growth. In those countries with higher value of the compositional index, the employment growth in manufacturing sector was generally higher. To analyse the characteristics of structural change in manufacturing sector, this paper classifies manufacturing industries into groups: one based on technology, one on orientation, one on wages and one on skills. The international comparison of manufacturing sector's employment patterns based on above four classifications are presented. International comparison suggests that Korean manufacturing sector move into jobs with more skills and knowledge The structural change of SMEs and large firms are compared based on above four classification methods. It is shown that SMEs' employment in low value sectors, that is low-technology, labor-intensive, tow-wage, and unskilled sectors, have risen faster than SMEs' employment in high-technology, science-based, high-wage and skilled sectors. Large firms' employment have been mainly increased in high value sectors. However, the employment growth of both large and small firms have been concentrated on production worker-intensively-using sectors, i.e. unskilled sectors. This widened the wage differential of production workers by firm sizes and concurrently led to severe shortage of production workers for SMEs, which has little ability to pay high wage to production workers because they usually belong to low-wage sectors. Korea need to push SMEs forward to high value sectors. The premise of that is, however, to pull large firms out of production worker-intensively-using sectors.

• 천문학회지
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• 제56권2호
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• pp.293-299
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• 2023

The Wide-Angle Polarimetric Camera (PolCam) is installed on the Korea's lunar orbiter, Danuri, which launched on August 5, 2022. The mission objectives of PolCam are to construct photometric maps at a wavelength of 336 nm and polarization maps at 461 and 748 nm, with a phase angle range of 0°-135° and a spatial resolution of less than 100 m. PolCam is an imager using the push-broom method and has two cameras, Cam 1 and Cam 2, with a viewing angle of 45° to the right and left of the spacecraft's direction of orbit. We conducted performance tests in a laboratory setting before installing PolCam's flight model on the spacecraft. We analyzed the CCD's dark current, flat-field frame, spot size, and light flux. The dark current was obtained during thermal / vacuum test with various temperatures and the flat-field frame data was also obtained with an integrating sphere and tungsten light bulb. We describe the calibration method and results in this study.

• 기술혁신학회지
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• 제17권3호
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• pp.490-518
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• 2014

본 연구는 전자부품연구원과 반도체 테스트용 프로브카드 회사간 기술이전 사례를 중심으로 기술이전이 사업화 성과까지 연계되기 위해 필요한 요인들을 분석하였다. 이러한 연구를 통해 실제 현장에서 가장 영향력 있는 기술이전의 성공요인을 살펴보고 정부정책과 기업전략 측면에서 기술이전과 기술사업화 성과를 창출하는 것을 주요 목적으로 한다. 국내외 선행연구 분석, 프레임워크 설정, 사례분석의 과정을 거쳐 기술 수요자, 기술 공급자, 이전 기술, 기술이전 과정 특성의 4가지 측면에서 시사점을 도출하였다. 연구결과 기술 수요자 특성은 신기술 이전획득전략 및 추진의지/보완 자산과 흡수 능력, 기술 공급자 특성은 기술이전 및 사업화 경험/기술이전과 연계한 사업화 지원의지/풍부한 이전 대상 기술군, 이전 기술 특성은 연구개발단계 및 기술분야/기존 기술과의 연계성, 기술이전 과정 특성은 기술이전 전담조직의 지원활동/기술 이전과정의 적극적 참여 등이 성공요인으로 도출되었다.

• 기술경영경제학회:학술대회논문집
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• 기술경영경제학회 1997년도 제11회 하계학술발표회 논문집
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• pp.222-223
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• 1997

인공씨감자 대량생산기술 상업화 사례는 모방 중심의 연구개발풍토 하에서 드물게 찾아볼 수 있는 출연(연)에 뿌리를 둔 Technology push형의 창조형 혁신사례이다. 본 논문은 모방형 연구개발풍토에서의 창조형 기술혁신사례를 분석함으로써 창조적 혁신의 성공요인을 발굴하여 지식창조 지향의 연구관리 모형 제시를 시도하였다. 출연(연)에 뿌리를 둔 Technology push형 혁신은 연구자 관점의 연구개발단계와 기업가 관점의 기업화 단계로 구분된다. 연구자 관점의 연구개발단계에서는 연구자의 고집과 집념 그리고 상사의 후원에 의해서 창의적인 아이디어가 살아남아 가능성 있는 기술로 발전할 수 있었으며, 연구성과에 대한 언론보도 및 외부세계의 관심과 기대, 민간기업의 참여는 연구자에게 심리적 압박(pressure)을 제공하나 연구자의 몰입을 촉진하는 효과를 가져왔다. 현장문제에 대한 몸으로의 체험 그리고 지식창조 체험은 중요한 암묵적 지식(tacit knowledge)이며, 연구자의 연구몰입을 가속화시켰다. 기업가 관점의 기업화 단계에서는 선진외국에서 검증된 기술을 도입개량하는데 익숙해 있고 새로운 창조형 혁신 경험이 없는 개발도상국의 입장에서 법적, 제도적, 사회적 요인 등 많은 장애요인이 등장하였다. 결국 새로운 개념의 혁신 추진과정에서 나타나는 많은 장애요인을 극복할 수 있는 지속적인 노력이 중요하였으며, 연구자의 기업가 정신(entrepreneurship), 참여기업의 기업화 의지와 노력이 중요하게 작용하였다. 또한 Technology push형 기술혁신에서 나타나는 소비자의 수용성을 제고시킬 수 있는 개선노력이 중요하다. 한편 Technology Push형 연구는 실용화까지 많은 시행착오 함께 약 10여년이라는 긴 시간이 필요하게 되는데, 장기간의 연구개발재원을 어떻게 조달하느냐가 창조적 기술혁신 성패의 관건이다. 이 과정에서 angel과 promoter의 역할이 중요하다.물질(hydrophilic components)은 30~33%정도의 분포를 보였고, 전염소 및 전오존 공정을 거친 처리수에서는 각각 62.2-62.8%, 43.9~49.0% 및 50~ 55%, 40~57% 정도의 분포를 보였다. 그리고 웅집-침전을 거친 처리수에서는 그 분포가 77~82%, 24-48%였다. 전주리 공정을 통하여 소수성 물질(byoghobic components)의 분포가 감 소하는 것을 볼 때 전염소 및 전오존 처리가 용존유기물의 응집에는 오히려 역 효과를 나타내는 것으로 판단된다. 것으로 판단된다.여 황토 2g에 대하여 Hieltijes and Lijklema 방법에 의해 Adsorbed-p, Nonapatite inorganic-P(NAI-P), Apatite-p, Organic-P로 구분하여 분석하고, 총인(Total Phosphorus)을 Standard Methods에 따라 Persulfate digestion후 0.45 m membrane 여지 여과하여 여액에 대해 PO3-4-P의 농도를 Ascorbic Acid 법으로 측정한 결과, NAI-P가 가장 큰 비율을 차지하였고, 부원료로 첨가된 금속 양이온 중 Fe3-이온이 흡착에 기여하는 정도가 가장 큰 것으로 평가되었다.다당류 T-AS의 보체 활성화 기작은 classical과 alternative complement pathway의 양 경로를 통해 활성화 되었다. T-AS 분획은 mouse내의 특정 혈청단백을 증가시켰으며, 항체 생성능의 증가가 관찰되어 effect T 세포의 활성화가 나타나고 있음을 알 수 있었다. T-AS는 생체내 투여시에 대식세포의 탐식능이 증진되었으며, 대식세포 기능 저해제에 의한 대식세포의 기능 저해 현상이 회복되었다. 이와 같은 결과들로부터, T-AS의 항암 활성은 활성화된 보체 성분 및 당 수용체들이 존재하는 대식세포의 개입을 시사한다.가능성과 그 방법의 모색에 관심을 갖게 되었으며