• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2003년도 유체기계 연구개발 발표회 논문집
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• pp.3-12
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• 2003

This paper reviews the present state of the art on the self-rectifying air turbines, which could be used for wave energy conversion. The overall performances of the turbines under irregular wave conditions, which typically occur in the sea, have been evaluated numerically and compared from the viewpoints of the starting and running characteristics. The types of turbine included in the paper are as follows: (a) Wells turbine with guide vanes (WTGV); (b) turbine with self-pitch-controlled blades (TSCB); (c) biplane Wells turbine with guide vanes (BWGV); (d) impulse turbine with self-pitch-controlled guide vanes (ISGV) and (e) impulse turbine with fixed guide vanes (IFGV). As a result, under irregular wave conditions it is found that the running and starting characteristics of the impulse type turbines could be superior to those of the Wells turbine. Moreover, the authors have explained the mechanism of hysteretic behavior of the Wells turbine and the necessity of links for improvement of the performance of ISGV.

• Journal of Microbiology and Biotechnology
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• 제16권1호
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• pp.15-19
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• 2006

A ferredoxin adsorbed hetero self-assembled layer was fabricated on chemically modified Au substrate, 4-Aminothiophenol (4-ATP) was deposited onto Au substrate and then N-succinimidyl-3-[2-pyridyldithio] propionate (SPDP) was adsorbed on the 4-ATP layer, since SPDP was used as a bridging molecule for ferredoxin adsorption, Ferredoxin/SPDP/4-ATP structured hetero layer was constructed because of strong chemical binding of ferredoxin, SPDP, and 4-ATP, The surface of the ferredoxin-adsorbed SPDP/4-ATP layer was observed by scanning tunneling microscopy, The hetero film formation was verified by surface plasmon resonance measurement. The current flow and rectifying property based on the scanning tunneling spectroscopy I-V characteristics was achieved in the proposed hetero layer. Thus, the hetero layer structure of ferredoxin functioned as a molecular diode with rectifying property, The proposed molecular diode can be usefully applied for the development of molecular scale electronic devices.

• The Korean Journal of Ceramics
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• 제4권1호
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• pp.43-46
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• 1998

We have investigated the formation and thermal stability of cobalt aluminide(CoAl) thin films on GaAs. In order to obtain cobalt-aluminide thin films, we deposited a multilayer of Co/Al on GaAs, and subsequently annealed the samples at 80$0^{\circ}C$ for 30 min. After annealing, single-phase cobalt aluminide was produced showing a flat and uniform interface with GaAs. which indicates that cobalt aluminide (CoAl) is thermally stable with GaAs. In addition, the adherence and mechanical properties of the as-deposited, and annealed Co/Al multilayer structure on GaAs are compatible with those required for device fabrication processes. The electrical property of the CoAl/GaAs contact shows rectifying characteristics, indicating that the diodes were usable as rectifying gate electrodes.

• 동양고전연구
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• 제34호
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• pp.7-38
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• 2009

"대학(大學)"에서는 오늘날 사회에서 필요로 하는 수신적(修身的)[도덕적(道德的)] 리더쉽에 대해 논의하고 있다. 대학에서는 먼저 강령(綱領)의 지취(指趣)로써 도덕적 지도자가 갖추어야 할 인성(人性)으로 두 가지를 들고 있는데, 그것은 첫째, 본성을 완성하고 자수(自修)를 완성한 사람이어야 한다. 두 번째는 사회의 구성원들이 각자의 위치에서 각자 맡은바 일을 하면서 정명(正名)을 이룰 수 있도록 하는 사회적 권위체이어야 한다는 것이다. 또한 "대학(大學)"의 수신적 지도자론에서는 단계와 연계 윤리가 있다. 그것은 수신으로부터 평천하의 단계적 발전이 있고, 또한 제가를 수신하듯이 하는 수신제가의 연계 윤리, 치국을 제가하듯이 하는 제가치국의 연계 윤리 등이 성립한다. 둘째로, 지어지선(止於至善)의 원칙이 있다. 그것은 명명덕(明明德)과 친민(親民)을 최고의 선에까지 이르게 하는 것이다. 다음으로 "대학(大學)"에서 말하는 도덕적 지도자가 이러한 인성을 갖추기 위해서 구체적으로 수행해야 할 두 가지의 학문강목(學問綱目)이 있는데, 그것은 크게 명덕지방(明德之方)과 친민지방(親民之方)의 두 단계의 공부라 볼 수 있다. 명덕지방(明德之方)에는 격물(格物), 치지(致知), 성의(誠意), 정심(正心)의 수기(修己)의 전제조건이 있는데, 격물치지(格物致知)란 도덕적 지식을 극에 이르게 하는 것이고, 성의정심(誠意正心)이란 자겸과 위선거악의 공부가 말할 수 있다. 명덕지방에는 또한 수신의 결과라 볼 수 있는 화민성속(化民成俗)의 평천하(平天下)가 있다. 화민(化民)은 사회 구성원 간의 화합과 평등, 정의의 실현을 말하고, 성속(成俗)은 혈구(?矩)의 도(道)로써 백성을 사랑할 것, 민심을 얻을 것, 덕(德)을 갖출 것, 충신을 실천하는 선인(善人)이 될 것, 생재(生財)의 도(道)를 이룰 것, 인(仁)을 실천할 것 등의 내용이 있다. 다음으로 다른 하나의 학문강목(學問綱目)은 친민지방(親民之方)이다. 친민지방은 수신의 공효로 나타나는 것으로, 여기에는 효제자(孝弟慈)의 수신제가(修身齊家) 연계 윤리와 충경치(忠敬治)의 제가치국(齊家治國)의 연계 윤리가 그 주된 내용이다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.306.2-306.2
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• 2014

전자기기의 휴대성과 이동성이 강조되고 있는 현대사회에서 비휘발성 메모리는 메모리 산업에 있어 매우 매력적인 동시에 커다란 잠재성을 지닌다. 이미 공정의 한계에 부딪힌 Flash 메모리를 대신하여 10nm 이하의 공정이 가능한 상변화 메모리(Phase-Change Memory, PRAM), 스핀 주입 자화 반전 메모리(Spin Transfer Torque-Magnetic RAM, STT-MRAM), 저항 변화 메모리(Resistive Random Access Memory, ReRAM)가 차세대 비휘발성 메모리 후보로서 거론되고 있으며, 그 중에서도 ReRAM은 빠른 속도와 낮은 소비 전력, CMOS 공정 호환성, 그리고 비교적 단순한 3차원 적층 구조의 특성으로 인해 활발히 연구되고 있다. 특히 최근에는 질화물 또는 질소를 도핑한 산화물을 저항변화 물질로 사용하는 ReRAM이 보고되고 있는데, 이들은 동작전압이 낮을 뿐만 아니라 저항 변화(Resistive Switching, RS) 과정에서 일어나는 계면 산화를 방지할 수 있으므로 ReRAM의 저항 변화 재료로서 각광받고 있다. 그러나 Cell 단위의 ReRAM 소자를 Crossbar Array 구조에 적용시켰을 때 주변 Cell과의 저항 상태 차이로 인해 전류가 낮은 저항 상태(LRS)의 Cell로 흘러 의도치 않은 동작을 야기한다. 이와 같이 누설 전류(Leakage Current)로 인한 상호간의 간섭이 일어나는 Cross-talk 현상이 존재하며, 공정의 간소화와 집적도를 유지하면서 이 문제를 해결하는 것은 실용화하기에 앞서 매우 중요한 문제이다. 따라서, 본 논문에서는 Read 동작 시 발생하는 Cell과 Cell 사이의 Cross-talk 문제를 해결하기 위해 자가 정류 특성(Self-Rectifying)을 가지는 실리콘 질화물/알루미늄 질화물 이중층(Si3N4/AlN Bi-layer)으로 구성된 ReRAM 소자 구조를 제안하였으며, Sputtering 방법을 이용하여 제안된 소자를 제작하였다. 전압-전류 특성 실험결과, 제안된 구조에 대한 에너지 밴드 다이어그램 시뮬레이션 결과와 동일하게 Positive Bias 영역에서 자가 정류 특성을 획득하였고, 결과적으로 Read 동작 시 발생하는 Cross-talk 현상을 차단할 수 있는 결과를 확보하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2009년도 제38회 동계학술대회 초록집
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• pp.49-49
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• 2010

Nanopiezotronics is an emerging area of nanotechnology with a variety of applications that include piezoelectric field-effect transistors and diodes, self-powered nanogenerators and biosystems, and wireless nano/biosensors. By exploiting coupled piezoelectric and semiconducting characteristics, it is possible for nanowires, nanobelts, or nanorods to generate rectifying current and potential under external mechanical energies such as body movement (handling, winding, pushing, and bending) and muscle stretching, vibrations (acoustic and ultrasonic waves), and hydraulic forces (body fluid and blood flow). Fully transparent, flexible (TF) nanogenerators that are operated by external mechanical forces will be presented. By controlling the density of the seed layer for ZnO nanorod growth, transparent ZnO nanorod arrays were grown on ITO/PES films, and a TF conductive electrode was stacked on the ZnO nanorods. The resulting integrated TF nanodevice (having transparency exceeding 70 %) generated a noticeable current when it was pushed by application of an external load. The output current density was clearly dependent on the force applied. Furthermore, the output current density depended strongly on the morphology and the work function of the top electrode. ZnO nanorod-based nanogenerators with a PdAu, ITO, CNT, and graphene top electrodes gave output current densities of approximately $1-10\;uA/cm^2$ at a load of 0.9 kgf. Our results suggest that our TF nanogenerators are suitable for self-powered TF device applications such as flexible self-powered touch sensors, wearable artificial skins, fully rollable display mobile devices, and battery supplements for wearable cellular phones.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.961-966
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• 2001

The Wells turbine is one of the simplest and most promising self-rectifying air turbines which are useful for the systems of alternative energy development in near future, and it is economically desirable from the point of view of the practical use, as well. To investigate the effect of blade sweep on the performance of the Wells turbine, computations of a fully 3-D Navier-Stokes are carried out under steady flow conditions of NACA0020 blade. It is known that the performance of the Wells turbine is considerably influenced by the blade sweep. An optimum blade sweep ratio(f=0.35) for the NACA0020 is found to be the most promising for the practical use, and this value is in good agreement with the previous experiments. It is also found that the overall turbine performance for the NACA0020 is better than that for the CA9.

• 한국해양공학회지
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• 제32권5호
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• pp.393-401
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• 2018

This paper reports a novel mobile-type wave energy harvesting system. The proposed system adopts a wave glider's propulsion mechanism. A wave glider's blades were mounted on a circular layout and generated a rotational motion. Combining the wave converting system with the wave glider, a mobile floating-type robotic buoy system was developed. It enabled the relocation of the buoy position, as well as station-keeping for long term operation. It had a small size and could efficiently harvest wave energy. A feasibility study and modeling were carried out, and a prototype system was constructed. Various tank tests were performed to optimize the proposed wave energy harvesting system.

• 사상체질의학회지
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• 제22권2호
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• pp.1-15
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• 2010

1. Objectives: This research aims to study the general overview of the theories on the covetous desire and the relevant theories on cultivation mentioned in "Donguisusebowon (東醫壽世保元): Theories on Nature and Conduct (性命論)". 2. Methods: The theories concerning the covetous desire introduced in Dong-Mu's manuscripts, including "Gyukchigo 格致藁)", "Yougocho (遺稿抄)", "Dongmuyougo (東武遺稿)" and "Jaejungsinpyun (濟衆新編)", were comprehensively reviewed. Furthermore, the significance of the theories on the covetous desire and the relevant theories on self-cultivation were studied within the context of "Donguisusebowon(東醫壽世保元): Theories on Nature and Conduct (性命論)". 3. Results and Conclusions: 1) Among the four covetous desires (selfishness (私心), indiscretion (放心), indolence(逸心), acquisitiveness (慾心)), selfishness and acquisitiveness are the interpersonal components that deal with the relationship between individuals, whereas indiscretion and indolence are the intra-personal or self-concerned components that deal with the internal desires within the individual. 2) In the early concepts on the quaternity explaining the perspective on the human being as introduced in Dongmu's earlier manuscripts, the four covetous desires are thought of as the most important etiological components, that are also intimately related to the theories of self-cultivation. 3) Among the concepts introduced in "Donguisusebowon (東醫壽世保元): Theories on Nature and Conduct (性命論)", viciousness (邪心) and negligence (怠心) are primary, intra-personal (self-concerned) desires that are henceforth matched to indiscretion and indolence, respectively, while selfishness (arrogance, assertiveness, indiscrimination and exaggeration (驕矜伐夸)) and acquisitiveness (violation, extravagance, slothfulness and stealthiness(奪侈懶竊)) are secondary, interpersonal desires. 4) 'Preserving the mind (存其心)' and 'rectifying the body (修其身)' are Methods of overcoming viciousness (indiscretion) and negligence (indolence), the intrapersonal desires, while 'nurturing the nature (養其性)' and 'propping the course (立其命)' are Methods of eliminating selfishness and acquisitiveness, the interpersonal desires, which ultimately each leads to the completion of Nature (性) and Conduct/Course (命).

• 한국식품영양학회지
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• 제30권5호
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• pp.867-879
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• 2017

This study investigated the factors affecting problematic drinking amongst the male university students of the Changwon area (n=367). The participants were divided into 3 groups, and undertook the self-report questionnaire survey. Based on the AUDIT (Alcohol Use Disorders Identification Test) guidelines, problematic drinking were rated as 'no problem' (28.8%), 'at-risk drinking' (41.7%), and 'alcohol abuse' (29.5%). Our study revealed that students living alone, indulged in more club activities, and drank more than 3 cans of carbonated drinks a day; this was significantly high on the AUDIT score (p<0.05). Participation in education was significantly higher (p<0.05), but intention to reduce the monthly alcohol consumption was significantly lower (p<0.001) in the alcohol abuse group. Recognition level of drinking cultures, drinking habits, AUDIT, and nicotine dependence were significantly higher in the alcohol abuse group (p<0.001). Recognition level of drinking cultures and nicotine dependence by the FTND (Fagerstrom Test for Nicotine Dependence) positively correlated with problematic drinking, whereas dietary guidelines and self-esteem showed a negative correlation with problematic drinking (p<0.05). Based on the results of multiple linear regression analysis, the factors affecting problematic drinking were recognition level of drinking cultures (${\beta}=0.47$, p<0.001) and nicotine dependence (${\beta}=0.23$, p<0.001). We conclude that implementation of health education for university students, would aid in rectifying the incorrect perception of drinking. Furthermore, both drinking and smoking should be considered simultaneously.