• 제목/요약/키워드: transport characteristic

검색결과 379건 처리시간 0.03초

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

  • 김상현;고창두
    • 한국해양환경ㆍ에너지학회지
    • /
    • 제6권3호
    • /
    • pp.16-25
    • /
    • 2003
  • 본 논문에서는 RORO선을 이용한 연안운송에 따른 CO₂가스 배출량과 NOx가스 배출량의 삭감 효과에 대하여 고찰한다. 먼저 국내 CO₂가스 배출량과 수출입 컨테이너화물의 물동량에 대하여 고찰한다. 다음에 RORO선의 특성, CO₂가스 배출량 기준과 NOx가스 배출량 기준에 대하여 고찰한다. 또한 경인지역과 부산항 사이의 수출입 컨테이너 화물의 운송에 있어서 도로운송을 연안운송으로 전환한 경우의 CO₂가스 배출량과 NOx가스 배출량 삭감 효과에 대하여 계산한다. 마지막으로 RORO선의 적재율과 연안운송 분담율 변화에 따른 CO₂가스 배출량과 NOx가스 배출량 변화에 대하여 조사한다. 본 논문의 결과를 통하여 수출입컨테이너 화물의 운송을 도로운송으로부터 RORO선을 이용한 연안운송으로 전환하는 것이 CO₂가스 배출량 삭감에는 효과적이나 NOx가스 배출량 삭감에는 큰 효과가 없는 것을 확인하였다.

  • PDF

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

  • 김인찬
    • 대한기계학회논문집B
    • /
    • 제20권9호
    • /
    • pp.3015-3029
    • /
    • 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
    • 센서학회지
    • /
    • 제25권5호
    • /
    • pp.310-319
    • /
    • 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.

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

  • 김범승
    • 한국철도학회논문집
    • /
    • 제17권4호
    • /
    • pp.307-312
    • /
    • 2014
  • 본 연구는 중앙선의 여객수송수요를 효율적으로 예측하기 위한 방법으로 계절성 요인을 고려한 ARIMA 모형을 제안하였다. 특히, 최근의 관광수요를 반영하기 위하여 2013년 4월 개통되어 운행되고 있는 중부내륙권 관광전용열차(O-train, V-train)의 수요를 포함하여 예측모형을 구축하였다. 이를 위하여 2005년 1월부터 2013년 7월까지의 월별 시계열 데이터(103개)를 사용하여 최적의 모형을 선정하였으며 예측결과 중앙선의 여객 수송수요는 지속적으로 증가할 것으로 나타났다. 구축된 모형은 중앙선의 단기수요를 예측하는데 활용이 가능하다.

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

  • 이상혁;김기웅
    • 한국가시화정보학회지
    • /
    • 제19권1호
    • /
    • pp.50-56
    • /
    • 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.

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

  • 남희;윤태순;이명길;이종철;홍의석
    • 한국ITS학회 논문지
    • /
    • 제4권3호
    • /
    • pp.73-78
    • /
    • 2005
  • 본 논문에서는 상호 캐패시터 (Bypass coupling Capacitor)를 이용하여 Transmission Zero를 구현함으로써 우수한 차단 응답 특성을 보이며, 또한 IDC (Interdigital Capacitor)을 사용함으로써 더욱 향상된 고조파 특성을 갖는 대역 통과 여파기를 설계 및 구현하였다. 지능형 교통시스템에 사용되고 있는 5.85 GHz의 중심 주파수에서 3 %의 대역폭을 갖도록 설계된 SIR (Stepped Impedance Resonator) 대역 통과 여파기는 1.8 dB의 삽입 손실과 20 dB의 반사 손실 특성을 갖도록 설계 되었으며, 제작된 대역 통과 여파기는 대역폭이 4.2 %로 1.9 dB의 삽입 손실과 15.4 dB의 반사 손실을 측정 결과에서 나타내었다.

  • PDF

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
    • /
    • 제16권12호
    • /
    • pp.1604-1612
    • /
    • 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.

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

  • 이정태;나선웅;신경;이영종;정홍배
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
    • /
    • pp.1046-1049
    • /
    • 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.

  • PDF