• 한국군사과학기술학회지
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• 제19권6호
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• pp.762-768
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• 2016

In this paper, a method for generating ranging signal to reduce the effects of interference and overcome intentional jamming is proposed in slow frequency hopping(SFH) communication system. A terminal uses ranging signal for initial Up-link synchronization in the frequency hopping communication systems using multi-terminal. However, ranging signal generated by unsynchronized terminal acts as an interference signal to another terminal. Therefore, we propose the design of the ranging signal with PN sequence in order to minimize the affection to the other terminal and simulated its performance. From the simulated result, we confirm synchronization performance.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2015년도 제49회 하계 정기학술대회 초록집
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• pp.87.2-87.2
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• 2015

Transparent conductors are commonly used in photoelectric devices, where the electric energy converts to light energy or vice versa. Energy consumption devices, such as LEDs, Displays, Lighting devices use the electrical energy to generate light by carrier recombination. Meanwhile, solar cell is the only device to generate electric energy from the incident photon. Most photoelectric devices require a transparent electrode to pass the light in or out from a device. Beyond the passive role, transparent conductors can be employed to form Schottky junction or heterojunction to establish a rectifying current flow. Transparent conductor-embedded heterojunction device provides significant advantages of transparent electrode formation, no need for intentional doping process, and enhanced light-reactive surface area. Herein, we present versatile applications of transparent conductors, such as NiO, ZnO, ITO in photoelectric devices of solar cells and photodetectors for high-performing UV or IR detection. Moreover, we also introduce the growth of transparent ITO nanowires by sputtering methods for large scale application.

• 복식
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• 제50권5호
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• pp.143-157
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• 2000

The pastiche is one of the most unique characteristics in the post-modern period. The pastiche fashion design is an intentional imitation expressed by deconstructivity of the design. It has become the major creation method of post-modern fashion by expressing the image from the variety and creativity. The concept of imitation in pastiche is the important fashion subject which lead the dynamics and creativities of fashion when It has freshness and spiritual energy. The values of creative area of pastiche are as fellows - firstly, it provides the delightness through the disharmony by being released from the restraint and stress of the restricted society. Secondly, the characteristics of restoration generated by development and reproduced from imitation has become an origin of creation. Thirdly, the boundary between subculture and high-class culture would be dismantled and the elements of these culture are mixed to become a unique image through its abundance and compromise vague public culture. Fourthly, the pastiche fashion dismantles the basic structure of clothes to endow avant-garde esthetic appreciation. Fifthly, the folklore fashion representing the culture of minority and neighboring countries would become a new destroying the historically fixed clue. sixthly, the reinterpretation of pastiche fashion discovers the new regulations and beauties from Imitation to provides tow Important elements of post-capitalism fashion, dynamics and creativity. Lastly the consistent adaptation of image of fashion design with strong technical and theoretical basis can establish new fashions of this era with its unique creativeness.

• 한국화재소방학회논문지
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• 제15권3호
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• pp.49-54
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• 2001

최근 전 세계적으로 개발을 위한 고의적인 방화와 기상이변에 의한 산림화재의 급증과 피해규모가 증가하는 경향을 보이고 있다. 이와 같은 대형 산림화재는 국내에서도 같은 경향으로 나타나고 있다. 산림화재에 가장 효과적인 대응 방법은 화재발생 후의 진압보다는 화재예방 활동이라고 볼 수 있으며, 우선적으로 시급한 연구과제는 산림화재 예방 시스템에 관한 연구라 할 수 있다. 본 연구에서는 산림화재의 종합적 위험등급 개발을 위해 산림화재에 영향을 미치는 인자들에 대해 실험 및 자료들을 분석·고찰하여 6개 인자에 대한 개별적 위험성을 나타내었으며 각 인자들의 위험성 기여도에 따른 가중치를 적용하여 종합위험 등급을 설정하였다.

• 동력기계공학회지
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• 제2권2호
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• pp.55-59
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• 1998

In practice, the property of nonlinearity is contained in all physical systems. In other word, all physical systems are nonlinear to some degree. Therefore it is important that we acquires a facility for analyzing feedback control systems with varying degrees of nonlinearity. To operate the system linearly over wide range of variation of signal amplitude and frequency, the system requires components of an extremely high quality. Such a system would probably be impractical in the view points of cost, space and weight. In this context of view, it is worth noting that the nonlinearities may be intentionally introduced into a system in order to compensate for the effects of other undesirable nonlinearities or to obtain better performance than what could be achieved using linear element only. A simple example of an intentional nonlinearity is the use of a nonlinear damped system to optimize response in accordance with the magnitude of error. In this paper, an on-off type nonlinear controller is introduced and the applicability and validity of a simple on-off controller are presented by the experimental result.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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• pp.1421-1423
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• 2003

Ultra Wideband is a new technology from commercial or civilian application viewpoint. It uses already allocated radio spectrum without causing significant interference to other users. It uses very low power, which is below the thermal noise of the receiver and is inherently difficult to detect by un-intentional users. Since, FCC approved the regulation for the commercial use of UWB in February 2002, the development of UWB technology is drastically gaining momentum. However, the technology itself is not new. It has already been used in military applications. UWB has three basic areas of applications, which are communication, positioning and imaging (UWB Microwave). The main commercial application will be for communication since it has very high data transfer rate for short distance. It can also be used for both indoor and outdoor 3-D positioning. Another important application is imaging like microwave remote sensing. An UWB sensor can pass through doors and walls and hence detect the objects inside the room. In this paper, we will introduce about UWB technology along with it’s various possible applications. We will also present some models to generate UWB signal and it’s analysis using signal-processing tools.

• 한국임상수의학회지
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• 제27권2호
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• pp.205-208
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• 2010

서울동물원에서 쟈넨 염소가 마콜에 의해 임신이 되었고, 세 마리의 히말라얀타알이 같은 종의 수컷에게 잘못 임신이 되었다. 의도적이던 우발적이던 다른 종간에 번식을 시켜 잡종을 생산하는 것은 종보전의 근본적인 원칙에 위배된다. 2002년 10월에 수입되었으며 염색체수가 염소와 같은 60개를 가진 마콜이 우연히 쟈넨과 교미를 하게 되었다. 사육사들의 기록을 토대로 교미날짜를 추정하였다. 히말라얀타알 3수와 쟈넨은 $PFG_2{\alpha}$ 제재 (dinoprost tromethamine) 15 mg을 근육주사하여 성공적으로 유산을 시켰다.

• 한국초등과학교육학회지:초등과학교육
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• 제36권2호
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• pp.163-179
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• 2017

This study is to examine whether elementary science textbooks in Korea and Singapore are applicable to flipped learning. By comparative study we sought to identifying appropriate features of science textbooks for learner-centered teaching. We analyzed text pages on the unit of 'Working of electricity' in Korean elementary science textbook for sixth grade and three chapters of 'Electric circuits, Using electricity, Conductors of electricity' in Singaporean elementary textbook, 'Science : My pals are here!'. We designed evaluating frameworks for science textbooks based on the four pillars of flipped learning. and applied it to 10 elementary teachers evaluate two textbooks. They evaluated textbooks with Likert Scale items and wrote detailed statements and exemplars about their choices. We analyzed the teachers' evaluative descriptions inductively and chose commonly mentioned characteristics. Based on the analysis, we got to the conclusion about specific features of two elementary science textbooks in terms of flexible environment, learning culture, intentional contents, and teachers' expertises. Implications for improving science textbooks towards flipped learning and learner-centered teaching through comparative study were discussed.

• Transactions on Electrical and Electronic Materials
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• 제14권5호
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• pp.242-245
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• 2013

Sn-doped $In_2O_3$ (ITO) thin films were prepared by radio frequency magnetron sputtering without intentional substrate heating on bare glass and $TiO_2$-deposited glass substrates to investigate the effect of a $TiO_2$ buffer layer on the electrical and optical properties of ITO films. The thicknesses of $TiO_2$ and ITO films were kept constant at 5 and 100 nm, respectively. As-deposited ITO single layer films show an optical transmittance of 75.9%, while $ITO/TiO_2$ bi-layered films show a lower transmittance of 76.1%. However, as-deposited $ITO/TiO_2$ films show a lower resistivity ($9.87{\times}10^{-4}{\Omega}cm$) than that of ITO single layer films. In addition, the work function of the ITO film is affected by the $TiO_2$ buffer layer, with the $ITO/TiO_2$ films having a higher work-function (5.0 eV) than that of the ITO single layer films. The experimental results indicate that a 5-nm-thick $TiO_2$ buffer layer on the $ITO/TiO_2$ films results in better performance than conventional ITO single layer films.

• Transactions on Electrical and Electronic Materials
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• 제12권5호
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• pp.209-212
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• 2011

Hafnium nitride (HfN) thin films were deposited onto a silicon substrate by inductive coupled nitrogen plasma-assisted radio frequency magnetron sputtering. The films were prepared without intentional substrate heating and a substrate negative bias voltage ($-V_b$) was varied from -50 to -150 V to accelerate the effects of nitrogen ions ($N^+$) on the substrate. X-ray diffractometer patterns showed that the structure of the films was strongly affected by the negative substrate bias voltage, and thin film crystallization in the HfN (100) plane was observed under deposition conditions of -100 $V_b$ (bias voltage). Atomic force microscopy results showed that surface roughness also varied significantly with substrate bias voltage. Films deposited under conditions of -150 $V_b$ (bias voltage) exhibited higher hardness than other films.