• 한국군사과학기술학회지
• /
• 제18권2호
• /
• pp.115-124
• /
• 2015

A methodology is proposed to estimate a trajectory of a flying target and its velocity using the time and frequency analysis of the acoustic signal. The measurement of sound emitted from a flying acoustic source with a microphone above a ground shall receive both direct and ground-reflected sound waves. For certain frequency contents, the destructive interference happens in received signal waveform reflected path lengths are in multiple integers of direct path length. This phenomenon is referred to as the acoustical mirror effect and it can be observed in a spectrogram plot. The spectrogram of acoustic measurement for a flying vehicle measurement shows several orders of destructive interference curves. The first or second order of curve is used to find the best approximate path by using nonlinear least-square method. Simulated acoustic signal is generated for the condition of known geometric of a sensor and a source in flight. The estimation based on cepstrogram analysis provides more accurate estimate than spectrogram.

• 한국정보통신학회논문지
• /
• 제7권4호
• /
• pp.736-742
• /
• 2003

지하공간인 터널에 대하여 이론적인 전파 경로손실 예측과 측정을 수행하였다. 터널 내 전파 경로 손실을 보다 정교하게 해석하기 위하여 터널의 단면적이 직사각형이고 직선구조의 터널을 선택하였다. 혼합도파관 모델, ray tracing모델을 이용하여 수신전력을 예측하였고, 측정시스템을 이용하여 송ㆍ수신기 사이의 거리에 따른 수신전력을 측정하였다. 주어진 터널 환경에서 터널 내 수신전력 측정값에 대한 회귀분석 값(0.0238dB/m)은 혼합도파관 EH1,2모드의 감쇄 값(0.0246dB/m)과 가장 근사한 결과를 보였다. 터널내 송ㆍ수신안테나 사이의 거리에 따른 수신 전력에 대한 Ray-tracing모델 시뮬레이션 결과와 측정값은 거의 일치하였다. 터널 내 RMS지연확산을 계산한 결과 송ㆍ수신안테나 사이의 거리가 증가할수록 RMS 지연확산 값은 증가하였고, 코히어런스 대역폭은 감소하였다.

• 한국통신학회논문지
• /
• 제38A권12호
• /
• pp.1110-1116
• /
• 2013

3D-ray tracing tool은 신호의 반사, 투과, 그리고 회절까지 고려하여 3차원 공간에서 더욱 정확한 네트워크 성능을 분석하기 위한 소프트웨어이다. 통신표준에서는 통신 자원을 효율적으로 제공하기 위해 소형셀을 포함한 Heterogeneous Networks (HetNets)을 도입하고 있다. 매크로셀에 비해 좁아진 커버리지를 사용하는 소형셀 환경에서는 3D 공간에서 성능분석이 중요해 졌다. 또한 지형구조와 건물의 배치 그리고 3D 빔포밍(beamforming) 기술 등의 사용으로 인해 네트워크 환경이 복잡해지기 때문에 기존의 2차원 수학적 모델들을 이용하여 성능을 분석하기에는 어려움이 따른다. 본 논문에서는 소형셀 네트워크 성능을 더욱 효율적으로 분석하기 위한 3D-ray tracing tool을 활용한 성능평가 방법을 소개한다. 성능평가 결과 기존의 방법보다 3D-ray tracing tool을 활용한 성능평가 방법이 소형셀 환경에서 더욱 적합하다는 결론을 내렸다.

• 전기학회논문지P
• /
• 제61권2호
• /
• pp.97-102
• /
• 2012

CPV system in the desert areas or areas near the equator, as is suitable for high-temperature region. As compared to silicon solar cells, CPV system have a high proportion of a BOS (balance of system). Solar cells because of its low proportion when designing a module technology is applied in a variety of ways. Applied to the CPV system is classified into two kinds of optical technology. One of those using fresnel lens uses refraction of light energy. The other is a mirror reflection of the structure using sprays. Both of these two ways to condense the sun to collect solar cell is a form of light. And goals by using a small solar cell materials is to produce more energy. In this paper, suitable for a domestic environment, with the aim CPV Manufacturing Technology, built on a variety of modular process technology to the development of a prototype performance analysis was carried out. In particular, silicone coated on the glass by the method of implementation of the Fresnel lens SOG(Silicon on glass) by applying the lens to absorb the solar spectrum was broad. In addition to, for the analyze to characteristics of the CPV module, developed CPV module performance and generating characteristics studied. These related technology through research and development of high-performance multi-junction solar cells, modules, development of concentrating solar power systems to facilitate the growth of the market is considered to be.

• 패션비즈니스
• /
• 제5권5호
• /
• pp.49-64
• /
• 2001

Fur is conceived as a material signifier, not only with its commodity value as luxury goods but also as its symbolic value as objects invested by one's libidinal desire. In this study, complex meanings of fur as multi-layered signs of political and sexual power focusing on fetishism shall be explored, especially on the spectacle fetishism acted by mass media during the anti-fur movement in the 1980s. In conjuction herewith, a highlight shall also be made to the symbolic value in fashion design since 1990s. In this study, first, as a theoretical investigation, fetishism, that has been traditionally considered only as sexual fetishism in fashion discourse will be explored in socio-economic level. Second, in historical context, how the meanings and values of fur have become realized in various cultural spaces, such as literature, art, film and finally, fashion will be viewed. In fashion, fur is a product of desire and power influenced by commodity fetishism as well as sexual fetishism. During the anti-fur movement, mass media has developed the concept of spectacle fetishism. Fur is a sign of animal-victim, and fur-clad women is viewed with images full of imperialsm, sexism and racism, thus act as derisive spectacles of consumerism. Since 1990s as a reflection on anti-fur movement, fetishistic characteristics, which challenge traditional operation method, are expressed by disguise, parody, and returning to the nature. First, fur as disguise is intended to hide sexually perverse, decadent characteristics and expensiveness of fur by texturing or patterning techniques. Second, fur as parody uses fake fur or dyed fur in order to satirize erotically and ethnographically fetishized meanings of fur. Third, aboriginal design of fur is adapted to use symbolic values outside the West, which can potentially mobilize antagonistic oppositions out of their fetishistic regimes. In conclusion, fur as sign of female sexuality and its libidinal profits of exchange, has significant symbolic values expressed in fashion.

• 한국콘텐츠학회논문지
• /
• 제9권8호
• /
• pp.219-230
• /
• 2009

본 연구는 한국과 일본의 신문광고가 사용하고 있는 광고소구는 구체적으로 어떻게 다른지에 대해 주목하고 있다. 본 연구에서는 광고가 문화의 반영물이라는 기본적인 가정 아래 한 일 두 나라의 광고를 비교 하였다. 실증연구에서는 한국과 일본의 신문광고를 내용분석이라는 연구방법을 통해 비교분석을 실시했다. 본 연구에서는 한국과 일본의 중앙지에 게재된 광고 411개(한국 209개, 일본 202개)를 대상으로 내용분석을 실시했다. 분석결과 한국과 일본 양국의 신문광고가 사용하는 광고소구는 통계적으로 유의한 차이가 있는 것으로 입증됐다. 이는 한국과 일본 양국의 문화의 차이에 기인한 것으로 해석될 수 있다. 앞으로 광고의 크리에이티브 전략, 매체 전략 등 다양한 분야에서의 한 일간 후속연구가 실시돼야 할 것으로 보인다.

• 한국콘텐츠학회논문지
• /
• 제18권8호
• /
• pp.197-209
• /
• 2018

본 연구의 목적은 질적 연구방법인 내러티브를 바탕으로 학교상담사의 삶 속에서 자녀양육 경험은 어떠하였으며 자녀양육 경험의 의미는 무엇이었는지 탐구하는 데 있다. 연구를 위해 8년 이상의 경력이 있고 학교상담사로 근무하며 자녀를 청소년 시기에 양육한 경험이 있는 두 명의 여성을 연구 참여자로 선정하였으며, 인터뷰를 거쳐 다음과 같이 연구 결과를 도출하였다. 3차원적 내러티브 탐구공간이라고 지칭되는 시간성 사회성 장소에 집중하여 학교상담사들의 자녀양육 경험을 구성하였는데 결과는 다음과 같다. 먼저 학교상담사들은 원가족에게 양육 받은 경험이 자녀에게 영향을 미치고 있음을 "통찰" 하였다. 상담공부 후 훈육과 강압적인 태도로 양육한 것에 대해 "반성과 사과"의 과정을 거쳐, 자녀를 이해하고 바람직한 부모-자녀관계를 형성하고자 노력하는 "충분히 좋은 양육자 되어가기"를 탐색할 수 있었다. 그리고 체험적 통찰을 통해 "진정한 상담사로 거듭나기"로 변모해 가고 있었으며, 이는 "온전히 기능하는 나"의 의미를 담고 있었다.

• 여성건강간호학회지
• /
• 제22권4호
• /
• pp.221-232
• /
• 2016

Purpose: The purpose of this study was to examine the applicability of a flipped learning course in Women's Health Nursing for nursing students. Methods: A total of 200 senior nursing students participated in flipped learning class of pregnancy, delivery and postpartum area, which included team-based learning and self-reflection for 8 weeks. One group pre-post test design was adopted and the changes in learning motivation and satisfaction were examined. In addition, reflective journals of the students were analyzed by making a qualitative content analysis. Results: Students showed a significant increase in score of learning motivation in the posttest (t=-4.47, p<.001). They had a mean of 3.90 in learning satisfaction out of possible five points. As a result of content analysis, three themes were selected: 'Improved attitude toward active learning', 'Burden caused by excessive workload', and 'Valuing to the team-based activity' To be specific, six sub-themes were selected, with three positive and three negative categories: 'improved class attention and understanding', 'positive class participation by preparing lessons in advance', 'peer interactions through discussion', 'A lot of time and effort consuming', 'stress caused by the burden of preparing lessons', and 'difficulties in cooperative activities'. Conclusion: This study supports and confirms that the flipped learning can be a creative instructional model of positive teaching-learning strategy in clinical nursing courses to enhance students' learning motivation.

• Current Photovoltaic Research
• /
• 제2권4호
• /
• pp.173-176
• /
• 2014

We have investigated the seed layer formation of front side contact using the inkjet printing process. Conductive silver ink was printed on textured Si wafers with 80 nm thick $SiN_x$ anti reflection coating (ARC) layers and thickened by light induced plating (LIP). The inkjet printable sliver inks were specifically formulated for inkjet printing on these substrates. Also, a novel method to prepare nano-sized glass frits by the sol-gel process with particle sizes around 5 nm is presented. Furthermore, dispersion stability of the formulated ink was measured using a Turbiscan. By implementing these glass frits, it was found that a continuous and uniform seed layer with a line width of $40{\mu}m$ could be formed by a inkjet printing process. We also investigated the contact resistance between the front contact and emitter using the transfer length model (TLM). On an emitter with the sheet resistance of $60{\Omega}/sq$, a specific contact resistance (${\rho}_c$) below $10m{\Omega}{\cdot}cm^2$ could be achieved at a peak firing temperature around $700^{\circ}C$. In addition, the correlation between the contact resistance and interface microstructures were studied using scanning electron microscopy (SEM). We found that the added glass particles act as a very effective fire through agent, and Ag crystallites are formed along the interface glass layer.

• Journal of Nutrition and Health
• /
• 제40권6호
• /
• pp.566-575
• /
• 2007

The purpose of this research was to understand how individuals reflect on the frequency and quantity of foods that they consume. Participants selected 5 males and 15 females aged 30 years or older were first interviewed on the frequency of their food consumption. Then based on this data, they were given a cognitive interview using the method of verbal proving. The individual cognitive interviews were recorded with consent while being conducted after complete approval by the Seoul National University Institution Review Board. The recorded material was evaluated using a thematic analysis after transcribing them into text. By analyzing stages of reflection, the major barriers to make the device difficult are revealed: 1) More difficulty in remembering events over the course of a full year due to diversification in the types of food that people consume 2) difficulty calculating the average for seasonal foods 3) difficulty estimating the amount of consumption from the photos presented 4) difficulty estimating amount of consumption from the quantity presented 5) difficulty processing foods that people think are healthy and foods are unhealthy simultaneously 6) difficulty having to consider foods where target food goes in as an ingredient; 7) difficulties arising from having to increase frequency when the amount consumed is higher than the quantity that is presented 8) difficulty having to combine the frequency and quantity of each food item when numerous foods are clustered into one category. These findings show that the less participants were involved in cooking, the more diverse their eating habits were, and the more they tried to adhere to rules of filling out the questionnaire, the more it was difficult for them to come up with an answer to the question being asked. It therefore seems necessary to construct a Food Frequency questionnaire that is attentive to these problems that arise from the recall stages.