• Title/Summary/Keyword: transport characteristic

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Study on the reduction of green house effect gas emission by RORO ship coastal transport of import-export container cargo (RORO선을 이용한 수출입컨테이너화물의 연안운송에 의한 온실가스 배출량 삭감에 관한 연구)

  • Kim S. H.;Koh C. D.
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.6 no.3
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    • pp.16-25
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    • 2003
  • In this paper, the reduction of green house effect gas CO₂ emission and NOx gas emission by using the RORO ship coastal transport of import-export container cargo was investigated. At first, the domestic CO₂ gas emission and the transportation of import-export container cargo were Investigated. Next, the characteristic of a RORO ship and CO₂ emission standard and NOx emission standard were investigated. And also, the reduction of CO₂ emission and NOx emission by the shift of coastal transport from land transport for the transportation of import-export container cargo between Kyongin area and Pusan Port were calculated. Finally, the change of CO2 and NOx gas emission due to the change of the share of coastal transportation and the load efficiency of RORO ship are investigated. The research results show that the shift of RORO ship coastal transport from land transport was very effective to reduce the CO₂ emission but it was no good to reduce the NOx emission.

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Fluctuation of Transport Properties of Random Heterogeneous Media (비정형 혼합재 이동성질의 변동)

  • Kim, In-Chan
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.20 no.9
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    • pp.3015-3029
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    • 1996
  • The notion of effective transport property of a heterogeneous medium implies that the medium is large enough that the ergodic theorem holds and local fluctuation of the property can be neglected. In case that the medium is not large enough compared to its characteristic microstructure length scale, the effective property fluctuates and differs from the value of the medium being large enough. As a representative transport phenomenon, diffusion was considered and the fluctuation of varying effective diffusion property, diffusion coarseness $C_k$, was defined as a quantifying parameter. Scaled effective diffusion property, $^*$>/k$_1$ and $C_k$ were computed for the two phase random media consisting of matrix of diffusion coefficient k$_1$ and spheres of diffusion coefficient k$_2$. Numerical simulations were performed by use of the so-called first passage time technique and data were collected for existing microstructure models of hard spheres(HS), overlapping spheres(OS) and penetrable concentric shells(PCS).

Innovative Differential Hall Effect Gap Sensor through Comparative Study for Precise Magnetic Levitation Transport System

  • Lee, Sang-Han;Park, Sang-Hui;Park, Se-Hong;Sohn, Yeong-Hoon;Cho, Gyu-Hyeong;Rim, Chun-Taek
    • Journal of Sensor Science and Technology
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    • v.25 no.5
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    • pp.310-319
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    • 2016
  • Three types of gap sensors, a capacitive gap sensor, an eddy current gap sensor, and a Hall effect gap sensor are described and evaluated through experiments for the purpose of precise gap sensing for micrometer scale movement, and a novel type of differential hall effect gap sensor is proposed. Each gap sensor is analyzed in terms of resolution and environment dependency including temperature dependency. Furthermore, a transport system for AMOLED deposition is introduced as a typical application of gap sensors, which are recently receiving considerable attention. Based on the analyses, the proposed differential Hall effect gap sensor is found to be the most suitable gap sensor for precise gap sensing, especially for application to a transport system for AMOLED deposition. The sensor shows resolution of $0.63mV/{\mu}m$ for the overall range of the gap from 0 mm to 2.5 mm, temperature dependency of $3{\mu}m/^{\circ}C$ from $20^{\circ}C$ to $30^{\circ}C$, and a monotonic characteristic for the gap between the sensor and the target.

Forecasting Passenger Transport Demand Using Seasonal ARIMA Model - Focused on Joongang Line (계절 ARIMA 모형을 이용한 여객수송수요 예측: 중앙선을 중심으로)

  • Kim, Beom-Seung
    • Journal of the Korean Society for Railway
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    • v.17 no.4
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    • pp.307-312
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    • 2014
  • This study suggested the ARIMA model taking into consideration the seasonal characteristic factor as a method for efficiently forecasting passenger transport demand of the Joongang Line. The forecasting model was built including the demand for the central inland region tourist train (O-train, V-train), which was opened to traffic in April-, 2013 and run in order to reflect the recent demand for the tourism industry. By using the monthly time series data (103) from January-, 2005 to July-, 2013, the optimum model was selected. The forecasting results of passenger transport demand of the Joongang Line showed continuous increase. The developed model forecasts the short-term demand of the Joongang Line.

Experimental Study on Structural and Functional Characteristics of Surface-Modified Porous Membrane (다공성 멤브레인의 표면 개질에 따른 구조 및 성능 특성에 대한 실험 연구)

  • Lee, Sang Hyuk;Kim, Kiwoong
    • Journal of the Korean Society of Visualization
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    • v.19 no.1
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    • pp.50-56
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    • 2021
  • With the advances in recent nanotechnology, mass transport phenomena have been receiving large attention both in academic researches and industrial applications. Nonetheless, it is not clearly determined which parameters are dominant at nanoscale mass transport. Especially, membrane is a kind of technology that use a selective separation to secure fresh water. The development of great separation membrane and membrane-based separation system is an important way to solve existing water resource problems. In this study, glass fiber-based membranes which are treated by graphene oxide (GO), poly-styrene sulfonate (GOP) and sodium dodecyl sulfate (GPS) were fabricated. Mass transport parameters were investigated in terms of material-specific and structure-specific dominance. The 3D structural information of GO, GOP, and GPS was obtained by using synchrotron X-ray nano tomography. In addition, electrostatic characteristic and water absorption rate of the membranes were investigated. As a result, we calculated internal structural information using Tomadakis-Sotrichos model, and we found that manipulation of surface characteristics can improve spacer arm effect, which means enhancement of water permeability by control length of ligand and surface charge functionality of the membrane.

A Stepped Impedance Resonator Bandpass Filter with Superior Cut-off Response for ITS Application (우수한 차단 특성을 갖는 ITS용 SIR 대역 통과 여파기)

  • Nam Hee;Yun Tae-Soon;Lee Myeong-Gil;Lee Jong-Chul;Hong Ui-Seok
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.4 no.3 s.8
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    • pp.73-78
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    • 2005
  • In this paper, a bandpass filter with excellent cut off characteristic due to transmission zero using bypass coupling capacitor and with superior harmonic characteristic by interdigital capacitor is suggested. The measurement results for SIR bandpass filter with bypass coupling capacitor and interdigital capacitor show that the insertion loss is less than 1.9 dB and the return loss is better than 15.4 dB with 4.2 % bandwidth at the center frequency of 5.78 GHz.

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A Study on the Fault Diagnosis of Roller-Shape Using Frequency Analysis of Tension Signals and Artificial Neural Networks Based Approach in a Web Transport System

  • Tahk, Kyung-Mo;Shin, Kee-Hyun
    • Journal of Mechanical Science and Technology
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    • v.16 no.12
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    • pp.1604-1612
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    • 2002
  • Rollers in the continuous process systems are ones of key components that determine the quality of web products. The condition of rollers (e.g. eccentricity, runout) should be consistently monitored in order to maintain the process conditions (e.g. tension, edge position) within a required specification. In this paper, a new diagnosis algorithm is suggested to detect the defective rollers based on the frequency analysis of web tension signals. The kernel of this technique is to use the characteristic features (RMS, Peak value, Power spectral density) of tension signals which allow the identification of the faulty rollers and the diagnosis of the degree of fault in the rollers. The characteristic features could be used to train an artificial neural network which could classify roller conditions into three groups (normal, warning, and faulty conditions) The simulation and experimental results showed that the suggested diagnosis algorithm can be successfully used to identify the defective rollers as well as to diagnose the degree of the defect of those rollers.

Characteristics of OLED by co-evaporation methode (Co-evaporation methode에 의한 OLED의 발광 특성)

  • Lee, Jung-Tae;Na, Sun-Woong;Shin, Kyung;Lee, Young-Jong;Chung, Hong-Bay
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07b
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    • pp.1046-1049
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    • 2002
  • In this study, We fabricated Organic Electroluminescence device, in order to improve the efficiency of Blue OLED in the full-color OLED. We made two sample. Sample A is that We used TPD(N,N‘-bis(3-methylphenyl)-N,N'-diphenylbenzidine} as hole transport layer(HTL), and Butyl-PBD(2-(4-Biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole) as emitting material layer(EML) and Alq3(8-Hydroxyquinoline, aluminum} as electron transport layer(ETL). Sample B is that we used TPD(N, N'-bis(3-methylphenyl)-N,N'-diphenylbenzidine} as HTL and co-evaporated Butyl-PBD and Alq3 as EML. We investigated the characteristic of brightness and current-:voltage. The sample B that co-evaporated Butyl-PBD and Alq3 as EML improved characteristic of brightness and current-voltage than sample A. Maximum luminescence of sample B is $310cd/m^2$ and threshold voltage is 7V.

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