• Title/Summary/Keyword: ramp system

Search Result 243, Processing Time 0.028 seconds

A Study on Development of Systems to Enforce the interfering Cars on the Ramp (끼어들기 단속시스템 개발 연구)

  • Lee, Ho-Won;Hyun, Cheol-Seung;Joo, Doo-Hwan;Jeong, Jun-Ha;Lee, Choul-Ki
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.11 no.5
    • /
    • pp.7-14
    • /
    • 2012
  • We frequently confront with cars interfering into our lane on the ramp. We suffered from serious traffic congestion due to the interfering cars. But the police enforcement has not done actively because it's hard to enforce. In this study, we have evaluated the systems to enforce cutting-in cars through the field test. Generally, the image processing method depends on the weather. To overcome this limitation we proposed a new algorithm combined with section detection method. In the filed test we concluded the results as follows. Whereas the violation detection rate of the general image processing was 58.2%, a new algorithm proposed by this study was 74.5%. And, an error rate enforcing vehicles that do not violate was 0.0%. Also, we can use the existing facilities, such as street light because of compact and lightweight systems which are integrated camera with controller. Therefore, we concluded that it is possible to enforce the interfering Cars using vehicle enforcement systems.

Development of Two Dimensional Filter for the Reconstructive Image Processing (영상 재구성 처리를 위한 이차원 필터의 구성)

  • Lee, Hwang-Soo
    • Journal of the Korean Institute of Telematics and Electronics
    • /
    • v.16 no.6
    • /
    • pp.16-21
    • /
    • 1979
  • Two dimensional kernels which reconstruct a tomographic image from a blurred one formed by simple back-projection are investigated in the frequency domain and their performances are compared. The kernels are derived from a point spread function of the tomographic system and have the form of a ramp filter modified by several window functions to suppress ringings or artifacts in the reconstruction. Computer simulation using computer-generated phantom image data with different filter functions has been carried out. In this simulation, it is found that the computation time for 2-D reconstruction is much less than that of 1-D convolution method by a factor of ten or more whereas the reconstructed image quality of the former is far poorer than the latter. In 2-D reconstruction heavy windowing results in less noisy reconstruction but details smear out in this case. The trade-offs between these points are considered.

  • PDF

Performance Predictions of Gas Foil Journal Bearing with Shim Foils (심포일을 갖는 가스 포일 저널 베어링의 성능 예측)

  • Hwang, Sung Ho;Moon, Chang Gook;Lee, Jong Sung;Kim, Tae Ho
    • Tribology and Lubricants
    • /
    • v.34 no.3
    • /
    • pp.107-114
    • /
    • 2018
  • This paper presents a computational model of a gas foil journal bearing with shim foils between the top foil and bumps, and predicts its static and dynamic performance. The analysis takes the previously developed simple elastic foundation model for the top foil-bump structure and advances it by adding foil models for the "shim foil" and "outer top foil." The outer top foil is installed between the (inner) top foil and bumps, and the shim foil is installed between the inner top foil and outer top foil. Both the inner and outer top foils have an arc length of $360^{\circ}$, but the arc length of the shim foil is shorter, which causes a ramp near its leading edge in the bearing clearance profile. The Reynolds equation for isothermal and isoviscous ideal gas solves the hydrodynamic pressure that develops within the bearing clearance with preloads due to the ramp. The centerline pressure and film thickness predictions show that the shim foil mitigates the peak pressure occurring at the loading direction, and broadens the positive pressure as well as minimum film thickness zones except for the shortest shim foil arc length of $180^{\circ}$. In general, the shim foil decreases the journal eccentricity, and increases the power loss, direct stiffness, and damping coefficients. As the shim foil arc length increases, the journal eccentricity decreases while the attitude angle, minimum film thickness, and direct stiffness/damping coefficients in the horizontal direction increase.

Physicochemical and Adsorptive Properties of Black Carbon for Radioactive Cesium under Various Combustion Conditions and Tree Species (연소 조건과 수종을 달리한 블랙카본의 물리화학적 성질 및 세슘의 흡착 특성)

  • Jeon, Sodam;Choung, Sungwook;Han, Weon Shik;Jang, Kyoung-Soon;Shin, Woosik;Hwang, Jeonghwan
    • Journal of Korean Society on Water Environment
    • /
    • v.33 no.6
    • /
    • pp.689-695
    • /
    • 2017
  • This study was carried out to investigate the physicochemical and adsorptive characteristics of black carbon (BC) materials for cesium in case of severe nuclear accidents. The BC was prepared with a xylem of oak and pine trees incompletely combusted with different ramp rate and final temperature. Carbon (C), hydrogen (H) and oxygen (O) atomic ratios, BET, pore structure, and zeta potential were characterized for the produced BC. A low cesium concentration ($C_w{\approx}10^{-7}M$) was used for sorption batch experiments. The H/C and O/C ratios of BC decreased with the increase of final temperature, which indicates a carbonization of the wood materials regardless of ramp rate and tree species. However, SEM images showed different pore structures depending on tree species such as steric and plate-like for oak-BC and pine-BC, respectively. The greatest sorption distribution coefficients of $K_{d,Cs}{\approx}1,200{\sim}1,800L\;kg^{-1}$ were observed for the oak-BC produced at $400^{\circ}C$, while comparatively low $K_{d,Cs}$ < $100L\;kg^{-1}$ for pine-BC. In addition, the sorption capabilities of BC declined with the increase of combustion temperature up to $600^{\circ}C$, because high temperature destroyed surface functionalities with the rise of ash components in the BC. Therefore, the sorption processes of BC for radioactive cesium are predominantly controlled by final production temperature of BC as well as raw materials (e.g., tree species).

Mooring chain fatigue analysis of a deep draft semi-submersible platform in central Gulf of Mexico

  • Jun Zou
    • Ocean Systems Engineering
    • /
    • v.14 no.2
    • /
    • pp.171-210
    • /
    • 2024
  • This paper focuses on the rigorous and holistic fatigue analysis of mooring chains for a deep draft semi-submersible platform in the challenging environment of the central Gulf of Mexico (GoM). Known for severe hurricanes and strong loop/eddy currents, this region significantly impacts offshore structures and their mooring systems, necessitating robust designs capable of withstanding extreme wind, wave and current conditions. Wave scatter and current bin diagrams are utilized to assess the probabilistic distribution of waves and currents, crucial for calculating mooring chain fatigue. The study evaluates the effects of Vortex Induced Motion (VIM), Out-of-Plane-Bending (OPB), and In-Plane-Bending (IPB) on mooring fatigue, alongside extreme single events such as 100-year hurricanes and loop/eddy currents including ramp-up and ramp-down phases, to ensure resilient mooring design. A detailed case study of a deep draft semi-submersible platform with 16 semi-taut moorings in 2,500 meters of water depth in the central GoM provides insights into the relative contributions of wave scatter diagram, VIMs from current bin diagram, the combined stresses of OPB/IPB/TT and extreme single events. By comparing these factors, the study aims to enhance understanding and optimize mooring system design for safety, reliability, and cost-effectiveness in offshore operations within the central GoM. The paper addresses a research gap by proposing a holistic approach that integrates findings from various contributions to advance current practices in mooring design. It presents a comprehensive framework for fatigue analysis and design optimization of mooring systems in the central GoM, emphasizing the critical importance of considering environmental conditions, OPB/IPB moments, and extreme single events to ensure the safety and reliability of mooring systems for offshore platforms.

Development of Korea-China Train Ferry System An Example of Short Sea Shipping in Northeast Asia

  • Lee, Jae-Wook;Lee, Seung-Hee;Kang, Young-Jin
    • Journal of Ship and Ocean Technology
    • /
    • v.10 no.3
    • /
    • pp.36-48
    • /
    • 2006
  • The train ferry, accommodating trains roll on and off, is often called as 'Railway on the Sea' or 'Blue High-way' since she can connect the railways or roads segregated by the sea and improve the accessibility and continuity of land transport systems. The ferry is especially appropriate to the intermodal transport routes mostly passing through the land but have relatively short sea segment. As the train ferry can considerably reduce the cost and time for cargo handling and modal shift and unnecessitates excessive initial investment on infrastructures such as large harbor cranes or vast container yards, introduction of train Ro-Ro ferries lessen the total transport cost for door-to-door transportation with full exploitation of the existing railway system. All the ports placed in Shandong, Liaoning and Jiangsu provinces of China are connected to the hinterlands via well developed railway and road systems. Therefore, realization of the Incheon-Yantai train ferry system will link Korea railways to TCR and the 4,131-kilometer-long Longhai-Lanxin Railway, along the famous Eurasian Continental Bridge. In the present paper, the Incheon-Yantai train ferry will be introduced as a good example of an efficient multimodal short sea shipping system for Northeast Asia.

Design of the timing controller for automatic magnetizing system

  • Yi Jae Young;Arit Thammano;Yi Cheon Hee
    • Proceedings of the IEEK Conference
    • /
    • 2004.08c
    • /
    • pp.468-472
    • /
    • 2004
  • In this paper a VLSI design for the automatic magnetizing system has been presented. This is the design of a peripheral controller, which magnetizes CRTs and computers monitors and controls the automatic inspection system. We implemented a programmable peripheral interface(PPI) circuit of the control and protocol module for the magnetizer controller by using a O.8um CMOS SOG(Sea of Gate) technology of ETRI. Most of the PPI functions has been confirmed. In the conventional method, the propagation/ramp delay model was used to predict the delay of cells, but used to model on only a single cell. Later, a modified "apos;Linear delay predict model"apos; was suggested in the LODECAP(LOgic Design Capture) by adding some factors to the prior model. But this has not a full model on the delay chain. In this paper a new "apos;delay predict equationapos;" for the design of the timing control block in PPI system has been suggested. We have described the detail method on a design of delay chain block according to the extracted equation and applied this method to the timing control block design.

  • PDF

Analysis on Required Capacity of Energy Storage System to Mitigate Wind Power Fluctuation (풍력발전기의 출력 안정화를 위한 에너지 저장장치 용량 산정 사례연구)

  • Kang, Min Hyeok;Chae, Sang Heon;Ahn, Jin Hong;Kim, Eel-Hwan
    • Journal of the Korean Solar Energy Society
    • /
    • v.37 no.6
    • /
    • pp.59-68
    • /
    • 2017
  • In accordance with the policy of local government, the large scale of wind farms have been installed in Jeju power system. However, The intermittent characteristics of wind power output may cause grid voltage and frequency variation, especially in weak power system. One of the solution to solve this problem is installation of Energy storage system (ESS). In this case, the ESS will regulate the active power generated from wind farm to mitigate fluctuation. Actually, the local government of Jeju island constructed ESS connected to Hangwon wind turbine in 2016. From this point, this paper analyzes requirement capacity of ESS to mitigate wind power fluctuation based on measured data from Hangwon wind turbine and ESS. The simulation results will be carried out by Matlab program.

Damping for Wind Turbine Electrically Excited Synchronous Generators

  • Tianyu, Wang;Guojie, Li;Yu, Zhang;Chen, Fang
    • Journal of Electrical Engineering and Technology
    • /
    • v.11 no.4
    • /
    • pp.801-809
    • /
    • 2016
  • The electrically excited synchronous generator (EESG) is applied in wind turbine systems recently. In an EESG control system, electrical torque is affected by stator flux and rotor current. So the control system is more complicated than that of the permanent-magnet synchronous generator (PMSG). Thus, the higher demanding of the control system is required especially in case of wind turbine mechanical resonance. In this paper, the mechanism of rotor speed resonant phenomenon is introduced from the viewpoint of mechanics firstly, and the characteristics of an effective damping torque are illustrated through system eigenvalues analysis. Considering the variables are tightly coupled, the four-order small signal equation for torque is derived considering stator and rotor control systems with regulators, and the bode plot of the closed loop transfer function is analyzed. According to the four-order mathematical equation, the stator flux, stator current, and electrical torque responses are derived by torque reference step and ramp in MATLAB from a pure mathematical deduction, which is identical with the responses in PSCAD/EMTDC simulation results. At last, the simulation studies are carried out in PSCAD software package to verify the resonant damping control strategy used in the EESG wind turbine system.

Progressive Iterative Forward and Backward (PIFAB) Search Method to Estimate Path-Travel Time on Freeways Using Toll Collection System Data (고속도로 경로통행시간 산출을 위한 전진반복 전후방탐색법(PIFAB)의 개발)

  • NamKoong, Seong
    • Journal of Korean Society of Transportation
    • /
    • v.23 no.5 s.83
    • /
    • pp.147-155
    • /
    • 2005
  • The purpose of this paper is to develop a method for estimation of reliable path-travel time using data obtained from the toll collection system on freeways. The toll collection system records departure and arrival time stamps as well as the identification numbers of arrival and destination tollgates for all the individual vehicles traveling between tollgates on freeways. Two major issues reduce accuracy when estimating path-travel time between an origin and destination tollgate using transaction data collected by the toll collection system. First, travel time calculated by subtracting departure time from arrival time does not explain path-travel time from origin tollgate to destination tollgate when a variety of available paths exist between tollgates. Second, travel time may include extra time spent in service and/or rest areas. Moreover. ramp driving time is included because tollgates are installed before on-ramps and after off-ramps. This paper describes an algorithm that searches for arrival time when departure time is given between tollgates by a Progressive Iterative Forward and Backward (PIFAB) search method. The algorithm eventually produces actual path-travel times that exclude any time spent in service and/or rest areas as well as ramp driving time based on a link-based procedure.