• Title/Summary/Keyword: Road field

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Rho-dependent Transcription Termination: More Questions than Answers

  • Banerjee Sharmistha;Chalissery Jisha;Bandey Irfan;Sen Ranjan
    • Journal of Microbiology
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    • v.44 no.1
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    • pp.11-22
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    • 2006
  • Escherichia coli protein Rho is required for the factor-dependent transcription termination by an RNA polymerase and is essential for the viability of the cell. It is a homohexameric protein that recognizes and binds preferably to C-rich sites in the transcribed RNA. Once bound to RNA, it utilizes RNA-dependent ATPase activity and subsequently ATPase-dependent helicase activity to unwind RNA-DNA hybrids and release RNA from a transcribing elongation complex. Studies over the past few decades have highlighted Rho as a molecule and have revealed much of its mechanistic properties. The recently solved crystal structure could explain many of its physiological functions in terms of its structure. Despite all these efforts, many of the fundamental questions pertaining to Rho recognition sites, differential ATPase activity in response to different RNAs, translocation of Rho along the nascent transcript, interactions with elongation complex and finally unwinding and release of RNA remain obscure. In the present review we have attempted to summarize 'the knowns' and 'the unknowns' of the Rho protein revealed by the recent developments in this field. An attempt has also been made to understand the physiology of Rho in the light of its phylogeny.

Performance and Adequate Usage of Deicing Materials (도로 융설제 성능 평가와 적정 사용량 산정)

  • Yun Duk-Geun;Jeong Jun-Hwa
    • International Journal of Highway Engineering
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    • v.8 no.1 s.27
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    • pp.55-64
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    • 2006
  • Deicing work is usually considered as a main part of winter road management activity. The deicing includes the physical method which removes snow with tools and the chemical method which melts snow with deicing materials. When removing snow using deicing materials, using excessive deicing materials will cause the environment and budget problems. When deicing materials are used less than the required amount, snow will remain on the road surface. In this research, the performance of deicing marerials has been evaluated and the amount of deicing materials has been determined by the laboratory and the field experiments. Also the adequate usages of deicing materials has been proposed.

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Effects of Ground Surface Condition on Steering Force for Tractors with Electronic Power Steering System (노면상태가 전동조향식 트랙터 조향력에 미치는 영향)

  • Lee S. S.;Lee K. S.;Park W. Y.;Kim S. Y.;Lee J. Y.;Mun J. H.
    • Journal of Biosystems Engineering
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    • v.30 no.6 s.113
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    • pp.327-332
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    • 2005
  • In this study, the electronic power steering control system was developed and it was carried out to investigate experimentally the effect of the steering force for the on-road and off-road. The electronic power steering control system was engineered new trend system of power steering control system for tractor. It was composed of the electronic controller, detector, motor and mechanism mounted on tractor chassis. It was tested at the field in condition of tractor traveling speed 0 km/h, 3 km/h, 8 km/h, 11 km/h, 15 km/h, 18 km/h, 22 km/h, 25 km/h for measuring a maximum steering force. As a speed of tractor increased, a steering force decreased regardless of on-road or off-road. In addition, it is sufficiently a possibility of application of the steering system of tractor.

A Comparative Study on Policy of Modal Shift for Enhancing of Eco-friendly Rail Freight Transportation (친환경수단으로서의 철도화물운송 증대를 위한 Modal Shift 정책 비교 연구)

  • Lee, Yoon-Mi;Moon, Dae-Seop;Yoo, Jae-Kyun
    • Proceedings of the KSR Conference
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    • 2008.06a
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    • pp.2455-2462
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    • 2008
  • Global warming has become one of the most important social responsibilities. After Kyoto protocol for greenhouse gas reduction by climatic change convention came into effect, developed countries are presenting various policies to reduce greenhouse gas that is produced in transport field. One of those policies is modal shift that change from road freight to sea, inland waterway and railway transportation that is eco-friendly. Because increase of road freight brings about road congestion and accident, logistics cost, air pollution and green house gases. Railways are superior to all other modes of transport in mass transportability, high speed, timeliness, safety and environmental-friendliness, but the railway industry has been pushed behind in competition. In developed country's government actively promoted relevant legislation, policies, and countermeasures known as modal shift policies to shift freight transport from road to large volume mode such as railway and ship. In this paper, we discuss the current situation in modal shift, compare it with cases in other countries EU and Japan, identify problems in Korea, and propose the following ways to enhance competitiveness of rail freight.

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Development of a Map Matching Method for Land Vehicles Navigation (차량 항법을 위한 지도 정합법 개발)

  • Sung Tae-Kyung;Pyo Jong-Sun
    • Journal of the Institute of Electronics Engineers of Korea SC
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    • v.42 no.4 s.304
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    • pp.1-10
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    • 2005
  • This paper presents a map matching method using multiple hypothesis technique(MHT) to identify the road that a land vehicle is located on. To realize a map matching method using MHT, Pseudo-measurements are generated utilizing adjacent roads of GPS/DR position and the MHT is reformulated as a single target problem. Since pseudo-measurements are generated using digital map, topological properties such as road connection, direction, and road facility information are considered in calculating probabilities of hypotheses. In order to improve the map matching performance under when bias errors exist in digital road map data, a Kalman filter is employed to estimate the biases. Field experimental results show that the proposed map matching method provides the consistent performance even in complex downtown areas, overpass/underpass areas, and in the areas where roads are adjacent in parallel.

Monte Carlo Simulation of MR Damper Landing Gear Taxiing Mode under Nonstationary Random Excitation

  • Lee, Hyo-Sang;Jang, Dae-Sung;Hwang, Jai-Hyuk
    • Journal of Aerospace System Engineering
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    • v.14 no.4
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    • pp.10-17
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    • 2020
  • When an aircraft is taxiing, excitation force is applied according to the shape of the road surface. The sprung mass acceleration caused by the excitation of the road surface negatively affects the feeling of boarding. This paper addresses the verification process of the semi-active control method applied to improve the feeling of boarding. The Magneto-Rheological damper landing gear model is employed alongside the control method. It is a Oleo-Pneumatic damper filled with a fluid having the characteristics of increasing yield stress when subjected to a magnetic field. The control method involves verifying Skyhook Control Type2 developed by Skyhook control. The Sinozuka white noise model that considers runway characteristics was employed for the road surface in the simulation. The runway road surface obtained through this model has stochastic characteristics, so the dynamic characteristics were analyzed by applying Monte-Carlo simulation. A dynamic analysis was conducted by co-simulating the landing gear model made by RecurDyn and the control method designed by Simulink. Simulation results show that the Skyhook Control Type2 method has the best control effect in the low speed range compared to the passive type (without control) and skyhook control.

In the middle of a perfect storm: political risks of the Belt and Road project at Kyaukphyu, Myanmar

  • Morris, David
    • Journal of Contemporary Eastern Asia
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    • v.20 no.2
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    • pp.210-236
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    • 2021
  • China's Belt and Road Initiative infrastructure connectivity and other projects are presented in much of the discourse as a grand strategy to trap developing nations in debt, to exert asymmetric power and construct a new world economic order. The asymmetric relationship between China and Myanmar might therefore be expected to generate a range of political risks for stakeholders. Myanmar itself presents a "perfect storm" of problems, with dysfunctional governance, civil conflict, under-development and growing economic dependence on China. The Kyaukphyu port project and associated Special Economic Zone in Myanmar's troubled Rakhine state is investigated as a case study of risks on the Belt and Road. While worst case fears China might seize military control of the port appear unlikely, at least in current conditions, empirical observation indicates the complexity on the ground generates an array of other risks - as well as opportunities, should conditions allow. Further, despite challenges and constrained capacity, Myanmar governments have demonstrated agency, including by re-negotiating control and costs of the Kyaukphyu project. The case underlines that conditions are more complicated than simply China's asymmetric power. A sceptical approach is taken to normative discourses in order to build inductive understanding of how stakeholders and local experts perceive dynamics underway. A political risk approach is deployed to develop a framework to identify, analyse and assess risks for actors in relation to the Kyaukphyu project. The research findings are presented on an interim basis, given current constraints on field interviews due to the current crisis.

Night-to-Day Road Image Translation with Generative Adversarial Network for Driver Safety Enhancement (운전자 안정성 향상을 위한 Generative Adversarial Network 기반의 야간 도로 영상 변환 시스템)

  • Ahn, Namhyun;Kang, Suk-Ju
    • Journal of Broadcast Engineering
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    • v.23 no.6
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    • pp.760-767
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    • 2018
  • Advanced driver assistance system(ADAS) is a major technique in the intelligent vehicle field. The techniques for ADAS can be separated in two classes, i.e., methods that directly control the movement of vehicle and that indirectly provide convenience to driver. In this paper, we propose a novel system that gives a visual assistance to driver by translating a night road image to a day road image. We use the black box images capturing the front road view of vehicle as inputs. The black box images are cropped into three parts and simultaneously translated into day images by the proposed image translation module. Then, the translated images are recollected to original size. The experimental result shows that the proposed method generates realistic images and outperforms the conventional algorithms.

Accuracy Analysis of Road Surveying and Construction Inspection of Underpass Section using Mobile Mapping System

  • Park, Joon Kyu;Um, Dae Yong
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.39 no.2
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    • pp.103-111
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    • 2021
  • MMS (Mobile Mapping System) is being used for HD (High Definition) map construction because it enables fast and accurate data construction, and it is receiving a lot of attention. However, research on the use of MMS in the construction field is insufficient. In this study, road surveying and inspection of construction structures were performed using MMS. Through data acquisition and processing using MMS, point cloud data for the study site was created, and the accuracy was evaluated by comparing with traditional surveying methods. The accuracy analysis results showed a maximum of 0.096m, 0.091m, and 0.093m in the X, Y, and H directions, respectively. Each RMSE was 0.012m, 0.015m, and 0.006m. These result satisfy the accuracy of topographic surveying in the general survey work regulation, indicating that construction surveying using MMS is possible. In addition, a 3D model was created using the design data for the underpass road, and the inspection was performed by comparing it with the MMS data. Through inspection results, deviations in construction can be visually confirmed for the entire underground roadway. The traditional method takes 6 hours for the 4.5km section of the target area, but MMS can significantly shorten the data acquisition time to 0.5 hours. Accurate 3D data is essential data as basic data for future smart construction. With MMS, you can increase the efficiency of construction sites with fast data collection and accuracy.

Implementation of Image Transmission Based on Vehicle-to-Vehicle Communication

  • Piao, Changhao;Ding, Xiaoyue;He, Jia;Jang, Soohyun;Liu, Mingjie
    • Journal of Information Processing Systems
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    • v.18 no.2
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    • pp.258-267
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    • 2022
  • Weak over-the-horizon perception and blind spot are the main problems in intelligent connected vehicles (ICVs). In this paper, a V2V image transmission-based road condition warning method is proposed to solve them. The encoded road emergency images which are collected by the ICV are transmitted to the on-board unit (OBU) through Ethernet. The OBU broadcasts the fragmented image information including location and clock of the vehicle to other OBUs. To satisfy the channel quality of the V2X communication in different times, the optimal fragment length is selected by the OBU to process the image information. Then, according to the position and clock information of the remote vehicles, OBU of the receiver selects valid messages to decode the image information which will help the receiver to extend the perceptual field. The experimental results show that our method has an average packet loss rate of 0.5%. The transmission delay is about 51.59 ms in low-speed driving scenarios, which can provide drivers with timely and reliable warnings of the road conditions.