• Journal of information and communication convergence engineering
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• 제8권3호
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• pp.281-288
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• 2010

This paper investigates the performance of IEEE 802.11p wireless access in vehicular environments (WAVE) system in small-scale fading models reported by Georgia Institute of Technology (Georgia Tech). We redesign the small-scale fading models to be applied to the computer simulation and develop the IEEE 802.11p WAVE physical layer simulator to provide the bit error rate and packet error rate performances. Moreover, a new channel estimator using decision directed channel estimation and linear minimum mean square error smoothing is proposed in order to improve the performance of the conventional least square channel estimator using two identical long training symbols. The simulation results are satisfactorily coincident with the scenarios of Georgia Tech report, and the proposed channel estimator significantly outperforms the conventional channel estimator.

• 한국전기전자재료학회논문지
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• 제16권12호
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• pp.1103-1109
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• 2003

Crystalline carbon nitride films have been deposited by RF reactive magnetron sputtering system with negative DC bias. The carbon nitride films deposited on various substrates showed ${\alpha}$- C$_3$N$_4$,${\beta}$-C$_3$N$_4$ and lonsdaleite structures through XRD and FTIR We can find the grain growth of hexagonal structure from SEMI photographs, which is coincident with the theoretical carbon nitride unit cell. When nitrogen gas ratio is 70 % and RF power is 200 W, the growth rate of carbon nitride film on quartz substrate is about 2.1 $\mu\textrm{m}$/hr.

• 한국해양공학회지
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• 제12권2호통권28호
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• pp.71-78
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• 1998

In this report for the assessment of creep properties of high-temperature tube materials in power plants, the long-time($10^4$~105h) creep life prediction by ISM for 2.25Cr1Mo steel was studied. It was clarified experimentally and quantitatively that the newly developed long-time creep life prediction equation was very coincident with the actual experimental data with high confidence, and the model was $t_r=\alpha\varepsilon_0^{\beta}\sigma^{-1}$.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.158.2-158
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• 2001

This paper introduces the design and implementation of a signal processing system for an airborne active homing radar system. This airborne active homing radar system uses the pulse Doppler radar of high PRF (Pulse Repetition Frequency) for computation of exact relative velocity of the target. This system carries out two operations mainly. The first is to transmit and receive microwave signal through the antenna. The second is to calculate the relative velocity of the target taking advantage of the Doppler frequency signal reflected from the target and detect the angle error between a target and an antenna LOS (Line Of Sight) to make the antenna direction coincident with the target. The signal processing system has a role of the latter.

• 대한전자공학회논문지
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• 제11권2호
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• pp.33-39
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• 1974

VNIC를 구성하는 방법으로서, 공통베이스접속회로의 베이스단자에 제어전압을 인가하는 방법을 제안하고 이것을 모델화한다. 단낙안정형은 제어압력을 입력전력에 종속하도록 함으로써 실현가능하며, 개방안정형은 입력전류에 종속인 출력전력에 비례하도록 함으로써 가능하다. 제안한 회로모델에 의하여, 회로를 구성하오 해석하여, 회로모델의 횡성기법의 타당성을 찾고, VNIC의 구성이론을 평이화하고자 한다.

• 한국축산시설환경학회지
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• 제4권2호
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• pp.175-182
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• 1998

For the recycling of swine takes 2 different steps in fermenting procedure, acidogenic reactor and methanogenic reactor, the activity of involved microbes can be maintained at the maximum level. This study showed applying 2 separate steps in anaerobic fermentation has improved fermenting efficiency over the conventional 1 step fermentation. Accordingly, the results are coincident with the hypothesis in which 2 steps acidogenic and methanogenic reactor fermentation is more efficient than conventional (1 step) fermentation that makes poisonous materials be obviate and abate. And the results also get the effective performance in the production of methane gas.

• 안보군사학연구
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• 통권7호
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• pp.129-154
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• 2009

The principles of military operations(principles of war) are the fundamental principles ruling warfighting that made based on the experiences of wars from the time of ancient Greeks to the World War II. Recent wars such as Iraq War showed us the change of environment of war and the style of waging a war. It is believed that future war will be executed with the style of Rapid Deceive Operations, Effect Based Operations, Network Centric Operations. Therefor the principles of war which we use should be reconsidered whether it is useful or not in future warfare. By considering the present principles of operation which are using in many countries and analysing the style of waging future war, we suggest new principles of operations : principle of gravity, principle of mass and dispersal, principle of disturbance, principle of speed, principle of paralysis, principle of synchronization and integration, principle of leadership, and principle of information.

• 한국연초학회지
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• 제5권2호
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• pp.25-32
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• 1983

To obtain basic information on the breeding of burley tobacco, classification of 41 varieties was carried out by using the cluster analysis of correlation coefficients and taxonomic distance based on twenty-one agromonic characters. Eight characters, such as days to flowering, length of flower axis, internode length, leaf length, yield, leaf angle to stem, vein angle to midrib and plant height, were useful in monothetic classification. Forty-one varieties were classified into four groups (I, II, III and IV) with weighted variable group method (WVGM ) and weighted jai. group method(WPGM), whereas the results classification of 33 varieties among them by WVGM were coincident with the results by WPGM. As for the characteristics of each group, group I related to late maturity, tall height and high yield, group II related to intermediate maturity, tall height and low yield, group 19 related to early maturity, intermediate height and low yield, and group W related to early maturity, short height and intermediate yield.

• 한국지역사회생활과학회지
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• 제18권4호
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• pp.681-686
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• 2007

This study was conducted to investigate the effects of the thermally different states of human feet on temperature regulation in winter season. Five healthy female students of age 20 volunteered as subjects to participate in the study. Physiological responses such as rectal temperature and skin temperatures as well as subjective responses of thermal comfort and thermal sensation were observed. Preferred clothing and preferred temperature were also evaluated in terms of behavioral temperature regulation. The results obtained through the experiment were statistically analyzed using paired t test. Rectal temperature was decreased greater (p<.01) and mean skin temperature was maintained higher (p<.01) in feet wanning than in feet cooling. Results of preferred clothing were coincident with those of general thermal sensation. There was a higher tendency to prefer temperature in feet wanning than feet cooling in the morning. It was concluded that keeping feet skin temperature lower in the early morning and higher in the late evening would be effective in terms of regulating circadian rhythm of core temperature.

• Journal of Mechanical Science and Technology
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• 제18권10호
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• pp.1849-1858
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• 2004

For examining friction-factor characteristics of round-hole pattern surfaces which are usually applied on damper seals, flat plate test apparatus is designed and fabricated. The measurement method of leakage and pressure distribution along round-hole pattern specimen with different hole area is described and a method for determining the Fanning friction factor is discussed. Results show that the round-hole pattern surfaces provide a much larger friction factor than smooth surface, and the friction factor vs. clearance behavior yields that the friction factor generally decreases as the clearance increases unlike the results of Nava's flat plate test. As the hole depth is decreased, the friction factor is increased, and maximum friction factor is obtained for 50% of hole area. Since the present experimental friction factor results show coincident characteristics with Moody's friction factor model, empirical friction factors for round-hole pattern surfaces are obtained by using the Moody's formula based on curve-fit of the experimental data. Results of Villasmil's 2D CFD simulation support the present experimental test result.