• Title/Summary/Keyword: 이상파

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A Study on the Co-relationship between Programming Ratio of Animation and the Preference of Broadcasting Channel : Focusing on the Programming Ratio of Terrestrial Broadcasting in the 1980s (방송채널의 애니메이션 편성비율과 선호채널이미지 축적간의 상관관계 연구 : 1980년대 지상파 방송채널 애니메이션 편성비율을 중심으로)

  • Han, Chang-Wan
    • Cartoon and Animation Studies
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    • s.13
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    • pp.211-221
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    • 2008
  • Animation programs are regarded as bad genre in the aspect of advertisement revenues due to relative low viewing ratios. But programming of animation can be considered positively in the aspect of channel loyalty and preference. This study is based on the assumption that if the scheduling of animation genres could bring out the improvement of channel image of broadcasting stations in the long term, the terrestrial broadcasters could reconsider the increase of animation programs. The research questions of this study are as follows: 1. What is the relationship between the programming ratio of animation genres and the concentration of viewing patterns? 2. How has the increase of animation programming influenced the channel image of broadcasters? 3. Why is it necessary to increase of reinforce the programming of animation genre in the new media platforms? The teenagers aged from 8 to 14 can generally make a decision which program they want to watch. Likewise, the adult viewers aged from 30 to 40 can make a selection which commodity they want to buy. The results of this study indicate that the adult viewers have showed the strong preference for the same broadcasting stations which they have been exposed to in their teenages. This result implies that in the new media environment, animation genre can lead the viewers' loyally and preference for the broadcasting channel for a long period.

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A study on the Factors Affected on the P- and S-wave Velocity Measurement of the Acrylic and Stainless Steel Core (아크릴 및 스테인리스강 시험편의 P-, S-파 속도 산출에 미친 영향 요인 고찰)

  • Lee, Sang-Kyu;Lee, Tae-Jong
    • Geophysics and Geophysical Exploration
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    • v.14 no.4
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    • pp.305-315
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    • 2011
  • A total of 864 measurements for P- and S- wave velocity of acrylic and stainless steel core samples have been performed with respect to their lengths and axial load applied. S-wave velocity measurement was much harder than P-wave velocity, so that it showed higher deviation in measured S-wave velocity with respect to repeated measurement, length of the cores, and the axial load applied. Velocity measurements for acrylic cores showed more stable and less than half of the variation between the measurements than the stainless steel cores. This seems to be come from better coupling between the transducers and acrylic cores than stainless cores, and from larger value of the first arrival time in a similar system noise environments. From the analysis of the 864 measurements, it is recommended that the length of the core be 60 ~ 90 mm, axial load between 20 kg (27.7 $N/cm^2$) and 30 kg (41.6 $N/cm^2$) for measurement of wave velocity of the acrylic and stainless steel cores. Especially for measuring S-wave velocity of stainless steel core, core length should be less than 50 mm, otherwise it will be affected by mode conversion or others. These results can be used in measurement and correction for system delay in wave velocity measurement for rock cores.

Seismic Velocity Change Due to Micro-crack Accumulation of Rock Samples from Seokmo Island, Korea (손상 진행에 따른 석모도 암석 시험편의 탄성파속도 변화)

  • Lee, Sang-Kyu;Choi, Ji-Hyang;Cheon, Dae-Sung;Lee, Tae-Jong
    • Geophysics and Geophysical Exploration
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    • v.14 no.4
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    • pp.324-334
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    • 2011
  • Seismic wave velocity change has been monitored due to the accumulation of micro-cracks by uniaxial loads on the rock samples from Seokmo Island with stepwise increase in 5 stages. After the load was applied up to 95% of UCS, P- and S-wave velocities varied in ranges of 0.9 ~ 18.3% and 2.8 ~ 14.8% of fresh rock sample velocities, respectively. Unlike seismic velocity of the dry rock samples that showed overall decreases after the loading, velocity changes of saturated rock samples were much more complicated. These seemed to be due to the mixture of two contradictory mechanisms; i.e. accumulation of micro-crack causes an increase in porosity and a decrease in wave velocity, while saturation causes an increase in wave velocity. Most of tested rocks showed a trend of velocity increase with low axial load and then velocity decrease at later stages. Starting stage of velocity decrease differs from samples to samples. After the failure of rock occurred, noticeable increases of porosity and decreases of wave velocity have been observed. It showed overall trend that the more the quartz contents and the lower the silicate, the higher the Young's modulus.

A Study on the Development of Harmonic Limit Device for Stabilizing Main Circuit Equipment of Train (열차운행 안정화를 위한 주회로 기기의 고조파 제한장치 개발에 관한 연구)

  • Kim, Sung Joon;Chae, Eun Kyung;Kang, Jeong Won
    • Asia-pacific Journal of Multimedia Services Convergent with Art, Humanities, and Sociology
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    • v.8 no.6
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    • pp.853-861
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    • 2018
  • This paper proposes the application of harmonic constraints to address the problems caused by abnormal voltage increases when electric railway vehicles are running. The AC line that supplies the train with power during operation is used to provide electricity of 25kV/60 Hz, but gradually the size and frequency of harmonics involved in the line are varied with the technological evolution of the railroad vehicle electrical equipment. An increase in heat losses due to the failure of the instrument transformer (PT), the main circuit device, which is a serious problem with the recent train safety operation, or to the main displacement voltage. When high frequency components are introduced through low frequency Transformers of the main circuit device, the high intensity of the components is caused by the high intensity of the core and the current flow of the parasitic core is increased, thus generating heat. To solve this problem, the recent adjustment of the sequence has applied artificial NOTCH OFF of the power converter. However, the method of receiving and controlling the OFF signal operates by interaction between the ground and the vehicle's devices, thus it is invalid in the event of failure, and an actual accident is occurring. Therefore, the harmonic currents were required to prevent possible flow of harmonics, and conducted a study to prevent accidental occurrence of train accidents and to verify feasibility of the device through the simulations of the train's experimental analysis and the simulations of the train for safe operation.

A Design of Wideband, High Efficiency Power Amplifier using LDMOS (LDMOS를 이용한 광대역, 고효율 전력증폭기의 설계)

  • Choi, Sang-Il;Lee, Sang-Rok;Rhee, Young-Chul
    • The Journal of the Korea institute of electronic communication sciences
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    • v.10 no.1
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    • pp.13-20
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    • 2015
  • Existing LDMOS power amplifier that used class-AB and doherty system shows 55% of efficiency in 60MHz narrow band. Because RRH has been applied to power amplifier at base station. It is required that over 100MHz expanded band and more than 60% high efficiency power amplifier. In this paper we designed class-J power amplifier using LDMOS FET which has over 60% high efficiency characteristic in 200MHz. The output matching circuit of designed class-J power amplifier has been optimized to contain pure reactance at second harmonic load and has low quality factor Q. As a measurement result of the amplifier, when we input continuous wave signal, we checked 62~70% of power added efficiency(PAE) in 2.06~2.2GHz including WCDMA frequency as a 10W class-J power amplifier.

Anomaly Detection Performance Analysis of Neural Networks using Soundex Algorithm and N-gram Techniques based on System Calls (시스템 호출 기반의 사운덱스 알고리즘을 이용한 신경망과 N-gram 기법에 대한 이상 탐지 성능 분석)

  • Park, Bong-Goo
    • Journal of Internet Computing and Services
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    • v.6 no.5
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    • pp.45-56
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    • 2005
  • The weak foundation of the computing environment caused information leakage and hacking to be uncontrollable, Therefore, dynamic control of security threats and real-time reaction to identical or similar types of accidents after intrusion are considered to be important, h one of the solutions to solve the problem, studies on intrusion detection systems are actively being conducted. To improve the anomaly IDS using system calls, this study focuses on neural networks learning using the soundex algorithm which is designed to change feature selection and variable length data into a fixed length learning pattern, That Is, by changing variable length sequential system call data into a fixed iength behavior pattern using the soundex algorithm, this study conducted neural networks learning by using a backpropagation algorithm. The backpropagation neural networks technique is applied for anomaly detection of system calls using Sendmail Data of UNM to demonstrate its performance.

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Case study on the lake-land combined seismic survey for underground LPG storage construction (LPG 지하저장기지 건설을 위한 수륙혼합 탄성파탐사 사례)

  • Cha Seong-Soo;Park Keun-Pil;Lee Ho-Young;Lee Hee-Il;Kim Ho-Young
    • 한국지구물리탐사학회:학술대회논문집
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    • 2002.09a
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    • pp.101-125
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    • 2002
  • A lake seismic survey was carried out to investigate possible geohazards for construction of the underground LPG storage at Namyang Lake. The proposed survey site has a land-lake combined geography and furthermore water depth of the lake is shallow. Therefore, various seismic methods such as marine single channel high resolution seismic reflection survey, sonobuoy refraction survey, land refraction survey and land-lake combined refraction survey were applied. Total survey amounts are 34 line-km of high resolution lake seismic survey, 14 lines of sonobuoy refraction survey, 890 m of land refraction survey and 8 lines of land-lake combined refraction survey. During the reflection survey, there were severe water reverberations from the lake bottom obscured subsurface profiling. These strong multiple events appeared in most of the survey area except the northern and southern area near the embankment where seems to be accumulated mainly mud dominated depositions. The sonobuoy refraction profiles also showed the same Phenomena as those of reflection survey. Meanwhile the results of the land-lake combined refraction survey showed relatively better qualities. However, the land refraction survey did not so due to low velocity soil layer and electrical noise. Summarized results from the lake seismic survey are that acoustic basement with relatively flat pattern appeared 30m below water level and showed three types of bedrock such as fresh, moderately weathered and weathered type. According to the results of the combined refraction survey, a velocity distribution pattern of the lake bottom shows three types of seismic velocity zone such as >4.5 km/s, 4.5-4.0km/s and <4.0km/s. The major fault lineament in the area showed NW-SE trend which was different from the Landsat image interpretation. A drilling was confirmed estimated faults by seismic survey.

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A study on the Frequency Allocation of Terrestrial UHDTV Broadcasting in 700MHz Band (700MHz 대역 지상파 UHD 방송 주파수 배치 방안 연구)

  • Lee, Sang Woon
    • Journal of Broadcast Engineering
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    • v.20 no.1
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    • pp.82-91
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    • 2015
  • The purpose of this paper is to propose the frequency allocation plan for the terrestrial UHDTV in 700MHz frequency band. Currently 700MHz frequency band is being requested by broadcasting, communication, and public safety sites for the use of UHDTV, LTE/LTE-A and PPDR (Public Protection and Disaster Relief) by each site. Validity and proper timing of each request is examined by references, and the frequency allocation plan is proposed. As results 9 channels and guard bands are allocated for the UHDTV service, under the consideration of two 10MHz frequency bands of the PPDR in700MHz band.

A Study on Tomographic Inversion of Crosshole Seismic Traveltimes in Transversely Isotropic Layers (횡적등방성 지층의 시추공 간 탄성파 주시 자료의 토모그래피 역산 연구)

  • 장성형;양승진;황세호;김중열
    • The Journal of Engineering Geology
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    • v.3 no.3
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    • pp.231-239
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    • 1993
  • This paper presents a result on the determination of velocity distribution by a tomographic inversion of crosshole seismic traveltimes in transversely isotropic(aniso tropic) media. The crosshole traveltimes used in this study are synthetic ones computed by ray tracing for some models having isotropic and transversely isotropic velocity distributions. The traveltimes are inverted by a general ART and ansotropic ART which considers the transversely isotropic effect during inver sion. The aniotropic ART gives accurate velodty distributions of transversely isotropic and isotropic models, while the isotropic ART determines accurate velocities only for the isotropic model but inaccurate for the transversely isotropic one. Therefore, the anisotropic ART may be used in case where no information is known on the isotropy or transverse isotropy of a survey area.

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Symmetrical Scanning Leaky Wave Antenaa Using Double Negative and Double Positive Transmission Line (Double Negative, Positive 전승 선로를 이용한 대칭적적인 주파수 스캐닝 누설파 안테나)

  • 이재곤;이정해
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.15 no.11
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    • pp.1069-1074
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    • 2004
  • In this paper, we have designed artificial double negative(DNG) transmission line composed of series inter-digital capacitor and two shunt inductive short stubs. This artificial DNG transmission line has the property of double positive (DPS) transmission line over some frequency ranges due to RF nature. In detail, this transmission line simultaneously has the contrary properties of DNG and DPS transmission line depending on operation frequency. DPS/DNG transmission line at leaky region is utilized to design frequency scanning antenna with backfire-to-endfire. We have simulated and measured the dispersion and for-field radiation beam patterns of symmetrical leaky wave antenna. The results show rough agreement.