• Journal of the Korea Institute of Military Science and Technology
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• v.19 no.6
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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.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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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.

• Journal of the Korean Society of Costume
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• v.50 no.5
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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.

• Fire Science and Engineering
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• v.15 no.3
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• pp.49-54
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• 2001

Recently, intentional arsons for exploitation and wildland fire caused by abnormal change of weather are increasing as well as the damage scale due to such fire in the world. The number of such big wildland fire is also increasing in Korea these days. Fire prevention activity can be said as more important than fire putting-out activity after a fire occurrence for the most effective way to cope with wildland fire, and the research on wildland fire prevention system is what we need to do urgently, In this study I examined and analyzed the experiments and data about the factors influencing wildland fire and stated the dangerousness of each factor for all of the 6 factors and set up the general dangerousness rating applying each factor's contribution to the dangerousness.

• Journal of Power System Engineering
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• v.2 no.2
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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.

• Proceedings of the KSRS Conference
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• 2003.11a
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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.

• Journal of Veterinary Clinics
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• v.27 no.2
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• pp.205-208
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• 2010

A female Saanen goat was pregnated by a Markhor (Capra falconeri) and three Himalayan tahrs (Hemitragus jemlahicus) were mismated by a conspecific male at Seoul zoo. Cross-breeding whether intentional or unintentional is considered opposite to the primary rule of species conservation. The Markhor, imported in October, 2002, having the number of chromosomes (2n = 60) same as domestic goats accidently mated with a Saanen goat. The mating time was back-calculated on the basis of zookeepers' record. The Saanen and three Himalayan tahrs (2n = 48) were successfully aborted by intramuscularly injecting 15mg $PFG_2{\alpha}$ (dinoprost tromethamine).

• Journal of Korean Elementary Science Education
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• v.36 no.2
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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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• v.14 no.5
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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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• v.12 no.5
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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.