• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2001.06a
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• pp.73-73
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• 2001

Boron-containing materials have several excellent properties, such as superlnardness, insulation and non-Rinear optical property. Recently, oxynitride compounds, such as Si(ON), Ti(ON), became the promising materials applied in diffusion barrier layer and solar cell. With the expectation of obtaining the hybrid property, we have firstly grown the BON thin film by radio frequency (R.F.) plasma enhanced metalorganic chemical vapm deposition (PEMOCVD) with 100 kHz frequency and trimethyl borate precursor. The plasma source gases used in this study were Ar and $H_2$, and two kinds of nhmgen source gases, $N_2$ and <$NH_3$, were also employed. The as-grown films were characterized by XPS, IR, SEM and Knoop microlhardness tester. The relationship between the films hardness and the growth rate indicated that the hardness of the film was dependent on several factors such as nitrogen source gas, substrate temperature and film thickness due to the variation of the composition and the structure of the film. Both nitrogen and carbon content could raise the film hardness, on which nitrogen content did stronger effect than carbon. The smooth morphology and continuous structure was benefit of obtaining high hardness. The maximum hardness of BON film was about 10 GPa.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2003.02a
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• pp.470-477
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• 2003

토양에 함유된 수분은 식물의 생육뿐만 아니라 식물뿌리의 호흡, 미생물 활성 및 토양의 화학적 상태에 큰 영향을 미친다. 즉, 토양수분은 물에 용해된 무기물과 토양 내의 양분을 녹여 식물 뿌리로 흡수될 수 있도록 이동시키며, 토양 속의 온도를 조절하여 뿌리의 영양분 흡수 능력을 향상시키는 기능을 한다. 또한 토양 속으로 수분이 이동하면서 고갈된 산소를 공급하는 등의 중요한 기능을 하고 있다 (Hillel, 1980). 따라서 토양 내 수분이 과다하거나 부족한 경우 인위적으로 최적 상태의 함수비로 조절하는 물 관리 기술의 중요성이 대두되고 있으며 물 관리 기술의 개발에서 가장 중요한 기술 중의 하나는 토양의 수분 함량을 온라인으로 계측하는 것으로서 관개배구 자동화 기술의 핵심부분이라고 할 수 있다. (중략)

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 1999.05a
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• pp.248-253
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• 1999

The content of this paper is concerned with the revision of technical specifications for the wireless microphone used in domestic. In order to revise the technical specifications at present, this paper analyzes radio interference to other station used adjacent band and introduces RF specifications of wireless microphone in worldwide. And the paper proposes draft revision of technical specifications for wireless microphone in accordance with domestic frequency environments.

• Journal of information and communication convergence engineering
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• v.18 no.2
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• pp.115-122
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• 2020

Audiovisual (AV) facilities such as TVs and signage are installed in various public places. However, audio cannot be used to prevent noise and interference from individuals, which results in a loss of concentration and understanding of AV content. To address this problem, a total technique for remotely listening to audio from audiovisual facilities with clean sound quality while maintaining video and lip-syncing through personal smart mobile devices is proposed in this paper. Through the experimental results, the proposed scheme has been verified to reduce system power consumption by 8% to 16% and provide real-time processing with a low latency of 120 ms. The system described in this paper will contribute to the activation of audio telehearing services as it is possible to provide audio remote services in various places, such as express buses, trains, wide-area and intercity buses, public waiting rooms, and various application services.

• Journal of the Korean Society for Heat Treatment
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• v.3 no.1
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• pp.1-7
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• 1990

To investigate the influence of r.f. power and electrode distance on the TiN deposition, TiN films were deposited onto STC3, STD11 steel and Si-wafer from gas mixtures of $TiC_4/N_2/H_2$ using the radio frequency plasma assisted chemical vapor deposition. The crystallinity of TiN film could be improved by the increase of r.f. power and the decrease of electrode distance. The TiN coated layer contains chlorine, its content were decreased with increasing r.f. power as well as decreasing electrode distance. And the thickness of deposited TiN was largely affected by r.f. power and electrode distance. The hardness of deposited TiN reached a maximum value of about Hv 2,000.

• Journal of Astronomy and Space Sciences
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• v.32 no.3
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• pp.167-180
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• 2015

Herein, we discuss the in situ measurement of the electron temperature in the ionosphere/plasmasphere by means of DC Langmuir probes. Major instruments which have been reported are a conventional DC Langmuir probe, whose probe voltage is swept; a pulsed probe, which uses pulsed bias voltage; a rectification probe, which uses sinusoidal signal; and a resonance cone probe, which uses radio wave propagation. The content reviews past observations made with the instruments above. We also discuss technical factors that should be taken into account for reliable measurement, such as problems related to the contamination of electrodes and the satellite surface. Finally, we discuss research topics to be studied in the near future.

• Journal of Korea Society of Digital Industry and Information Management
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• v.6 no.2
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• pp.143-151
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• 2010

RFID System of Ubiquitous which is one of problem that may occur in a process of replacing bar code in 21st century. Ubiquitous computer environment should be considered to be most important task to protect information. For introduction, this presentation going to discuss the background information, the purpose of Ubiquitous and potential problems in individual privacy in computer environment. In main part, the content will handle the practices and weakness in security of computer environment in Ubiquitous. Last part of presentation going to examine, futuristic views in solving existing problems with alternative solutions to prohibit invasion in privacy.

• The Bulletin of The Korean Astronomical Society
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• v.38 no.1
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• pp.33.2-33.2
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• 2013

We present 12CO ($J=1{\rightarrow}0$) observations of a set of local galaxies (0.04 < z < 0.08) with a large cool gas reservoir, dubbed "HI Monsters". The data were obtained using the Redshift Search Receiver (RSR) on the Five College Radio Astronomy Observatory (FCRAO) 14 m telescope. The sample consists of 20 galaxies with $M_{HI}$ > $3{\times}10^{10}M_{\odot}$ identified by the ALFALFA survey and 8 additional objects with comparable HI mass from a separate LSB galaxy study ($M_{HI}$ > $1.5{\times}10^{10}M_{\odot}$). Our sample selection is purely based on the amount of neutral hydrogen in galaxies, thereby providing a chance to study how atomic and molecular gas relate to each other in these extremely HI-rich systems. We have detected CO in 15 out of 20 ALFALFA selected HI Monsters and 4 out of 8 LSB HI Monsters. We present the global molecular gas properties of the sample and discuss how their molecular gas properties correlate with their star formation activities.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.35 no.9A
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• pp.896-905
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• 2010

In this paper, we present a new sensing method based on phase entropy. Entropy is a measurement which quantifies the information content contained in a signal. For the PSK modulation, the information is encoded in the phase of the transmitted signal. By focusing on phase, more information is collected during sensing, which suggests a superior performance. The sensing based on Phase entropy is not limited to PSK signal. We generalize it to PAM signal as well. It is more advantageous to detect the phase. The simulation results have confirmed the excellent performance of this novel sensing algorithm.

• Korean Journal of Remote Sensing
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• v.17 no.2
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• pp.141-153
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• 2001

A semi-empirical polarimetric backscattering model for bare soil surfaces is presented. Based on measurements by using polarimetric scatterometers and the JPL AirSAR, as well as the theoretical models, the backscattering coefficints $\sigma$$^0_w$, $\sigma$$^0_{hh}$ and $\sigma$$^0_{vh}$, and the parameters of the copolarized phase-difference probability density function, namely the degree of correlation $\alpha$ and the copolarized-phase-difference $\zeta$, are modeled empirically in terms of the volumetric soil moisture content m$_v$ and the surface roughness parameters $k_s$ and $k_l$, where k=2$\pi$f/c, s is the rms height and l is the correlation length.