• Title/Summary/Keyword: long-take

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슬라이딩 모드 제어를 이용한 시각센서 기반의 차선변경제어 시스템 설계 (Vision-Based Lane Change Maneuver using Sliding Mode Control for a Vehicle)

  • 장승호;김상우
    • 한국자동차공학회논문집
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    • 제8권6호
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    • pp.194-207
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    • 2000
  • In this paper, we suggest a vision-based lane change control system, which can be applied on the straight road, without additional sensors such as a yaw rate sensor and a lateral accelerometer. In order to reduce the image processing time, we predict a reference line position during lane change using the lateral dynamics and the inverse perspective mapping. The sliding mode control algorithm with a boundary layer is adopted to overcome variations of parameters that significantly affects a vehicle`s lateral dynamics and to reduce chattering phenomenon. However, applying the sliding mode control to the system with a long sampling interval, the stability of a control system may seriously be affected by the sampling interval. Therefore, in this paper, a look ahead offset has been used instead of a lateral offset to reduce the effect of the long sampling interval due to the image processing time. The control algorithm is developed to follow the desired trajectory designed in advance. In the design of the desired trajectory, we take account of the constraints of lateral acceleration and lateral jerk for ride comfort. The performance of the suggested control system is evaluated in simulations as well as field tests.

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What is the Role of Co-coordinator?: From Internship's Experience

  • Onishi, Mai;Morimoto, Emi;Kamada, Mahito
    • 공학교육연구
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    • 제15권5호
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    • pp.42-46
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    • 2012
  • Graduate Students in engineering at The University of Tokushima can take part in an educational program which is offered long-term internship opportunities (at a company or the government). Onishi, one of authors, took part in this educational program. She is studying environmental conservation at the university and is interested in environmental conservation activities led by residents. Striking a balance between environmental conservation and human economic activities is seen as important to society. However, the continuing in environmental conservation activities is difficult. Therefore, collaborative activities attract attention as a way of the continuing in environmental conservation activities. A person called "co-coordinator" is a key to make many people to participate in the sustainable collaboration activities. The main role of co-coordinator is connecting people who are interested in environmental conservation activities. The purpose of joining in environmental conservation activities is different from person to person depending on where they belong to or where they live. Onishi took part in the educational program to learn the techniques of adjusting the differing interests. She did her internship at environmental consulting company in Kamikatsu town, Tokushima prefecture. She participated in several environmental conservation activities and work experience as a coordinator. Through this experience, she learned not only the technique but also the difficulty of the work. This paper reports the results obtained from her experience.

An Opportunity-based Age Replacement Policy with Warranty Analysed by Using TTT-Transforms

  • Iskandar, Bermawi P.;Klefsjo, Bengt;Sandoh, Hiroaki
    • International Journal of Reliability and Applications
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    • 제1권1호
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    • pp.27-38
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    • 2000
  • In a recent paper Iskandar & Sandoh (1999) studied an opportunity-based age replacement policy for a system which has a warranty period (0,S]. When the system fails at age x $\leq$ S a minimal repair is performed. If an opportunity occurs to the system at age x, S $\leq$ x $\leq$ T, we take the opportunity with probability p to preventively replace the system, while we conduct a corrective .replacement when its fails in (S,T). Finally, if its age reaches T, we perform a preventive replacement, Under this policy the design variable is T. For the case when opportunities occur according to a homogeneous Poisson process, the long-run average cost of this policy was formulated and studied analytically by Iskandar & Sandoh (1999). The same problem is here analysed by using a graphical technique based on scaled TTT-transforms. This technique gives, among other things, excellent possibilities for different types of sensitivity analysis. We also extend the discussion to the situation when we have to estimate T based on times to failure.

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Evaluation of Plasma Spray Hydroxy Apatite coatings on Metallic Materials

  • Take, S.;Mitsui, K.;Kasahara, M.;Sawai, R.;Izawa, S.;Nakayama, M.;Itoi, Y.
    • Corrosion Science and Technology
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    • 제6권6호
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    • pp.286-290
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    • 2007
  • Biocompatible Hydroxy apatite (HAp) coatings on metallic substrate by plasma spray techniques have been developed. Long-term credibility of plasma spray HAp coatings has been evaluated in physiological saline by electrochemical measurements. It was found that the corrosion resisitance of SUS316L based HAp/Ti conbined coatings was excellent even after more than 10 weeks long-term immersion. It was shown that postal heat treatment improved both the crystallinity and corrosion resistance of HAp. By lowering cooling rate during heat treatment process, less cracks produced in HAp coating layer, which lead to higher credibility of HAp during immersion in physiological saline. The ICP results showed that the dissolution level of substrate metallic ions was low and HAp coatings produced in this research can be acceptable as biocompatible materials. Also, the concentration of dissolved ions from HAp coatings with postal heat treatment was lower compared to those from samples without postal heat treatment. The adherence of HAp coatings with Ti substrate and other mechanical properties were also assessed by three-point bending test. The poor adhesion of HAp coating to titanium substrate can be improved by introducing a plasma spray titanium intermediate layer.

전형적(典型的)인 학질의 증례(證例) 보고(報告) (Case study on the Fever pattern of Malaria)

  • 박재현
    • 대한한방내과학회지
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    • 제19권2호
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    • pp.451-457
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    • 1998
  • This study was performed on the bases of clinical consideration about patient who has malaria. The symptoms of malaria are periodic alternating of chills and fever on everyone, two or three days. The patients feel a chill at the first time of malaria, and have a fever, headache and sweating at the next time. The long cycle of malarial fever such as every 2 or 3 days means that it takes a turn for the worse. In this study, oriental medicine was taken based on the oriental medicine principle such as Dalwonum(達原飮), Sosihotang(小柴胡湯) and Bojungikgitang(補中益氣湯), and the patients take a turn for the better. In the process of treatment if there is no fever in the expected date of the malarial fever, it is sure to have fever in the next expected date. It is favorable that patients lose the chills first and the fever lately in the process of treatment, and we can explain that supporting healthy energy to eliminate evil(扶正祛邪). The long cycle of malarial fever such as every 4, 6 or 9 days means that it is just before the recovery.

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초고압 송전선로용 V련 현수애자장치의 개발 (A Development of V type Suspension String Set for UHV Transmission Lines)

  • 손흥관;이형권;금의연;민병욱;최진성;최인혁
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 하계학술대회 논문집 A
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    • pp.497-499
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    • 2004
  • Due to a typhoon named MAEMI on Sep12, 2004, 7 transmission towers collapsed and 3 were damaged in the Gyeongnam and Busan areas. These caused long-term black-outs in Goeje-do. When a transmission tower collapses or is damaged, Construction will take more than 2 months and this will be accompanied by long-term black-outs. Therefore a temporary iron pole is used in such emergencies. Current temporary rehabilitation angle steel iron Pole consistes of around 800 members, 2,800 bolts and it takes about 5 days to construct a temporary transmission line. Consiquently wide black-outs occur during the construction of the temporary transmission line. To reduce black-out time, the construction period must be reduced as much as possible. This paper presents new methods to reduce temporary transmission line construction time to within 48 hours by applying a self-reliance assembling method instead of the current man power assembling method and by modulizing each angle steel with duralumin.

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A Study on the Determinants of Bilateral Trade : Evidence from China and US

  • He, Yugang
    • 동아시아경상학회지
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    • 제7권1호
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    • pp.27-38
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    • 2019
  • Purpose - Recently, the trade war between China and US has been escalating, which has also attracted worldwide attention. Based on this background, this paper sets China and US as an example to explore the determinants of bilateral trade between China and US. Research design, date, and methodology - A quarterly data from the 2000-Q1 to the 2017-Q4 will be used to perform an empirical analysis under some econometric approaches such as the fully modified least squares and the vector error correction estimates. Result - The results illustrate that the two economic entities of China and US have the greatest positive effect on bilateral trade between China and US. The real exchange rate has a positive effect on bilateral trade between China and US. The nominal exchange rate has a negative effect on bilateral trade between China and US in the short run. US's average price has a positive effect on bilateral trade between China and US in the short run. China's average price has a negative effect on bilateral trade between China and US in the short run. Meanwhile, the bilateral trade between China and US also suffers from the economic crisis happened in 2008. Even through the bilateral trade between China and US in the short run is deviate from the long-run equilibrium, there exist an error correction mechanism back to the long-run equilibrium. Conclusion - This paper provides some empirical evidences for both governments. Based on the results of this paper, both governments should take corresponding measures to promote the development of bilateral trade between China and US.

Impulse Response of Inflation to Economic Growth Dynamics: VAR Model Analysis

  • DINH, Doan Van
    • The Journal of Asian Finance, Economics and Business
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    • 제7권9호
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    • pp.219-228
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    • 2020
  • The study investigates the impact of inflation rate on economic growth to find the best-fit model for economic growth in Vietnam. The study applied Vector Autoregressive (VAR), cointegration models, and unit root test for the time-series data from 1996 to 2018 to test the inflation impact on the economic growth in the short and long term. The study showed that the two variables are stationary at lag first difference I(1) with 1%, 5% and 10%; trace test indicates two cointegrating equations at the 0.05 level, the INF does not granger cause GDP, the optimal lag I(1) and the variables are closely related as R2 is 72%. It finds that the VAR model's results are the basis to perform economic growth; besides, the inflation rate is positively related to economic growth. The results support the monetary policy. This study identifies issues for Government to consider: have a comprehensive solution among macroeconomic policies, monetary policy, fiscal policy and other policies to control and maintain the inflation and stimulate growth; set a priority goal for sustainable economic growth; not pursue economic growth by maintaining the inflation rate in the long term, but take appropriate measures to stabilize the inflation at the best-fitted VAR forecast model.

노인데이케어센터의 지역융합형 발전방향 (Development of Daycare Center for Senior Users as Community-Cohesive Facility)

  • 한정원
    • 한국산학기술학회논문지
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    • 제15권3호
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    • pp.1489-1495
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    • 2014
  • 고령화시대를 맞아서 한국은 2008년부터 노인장기요양보험을 실시하면서 노인부양부담을 가족으로부터 국가의 책임으로 인식하기 시작하였다. 데이케어센터(주간보호센터)는 사회적 보살핌을 제공하는 시설 중의 하나로 입소생활시설과는 다른 주간이용시설인데 설립초기 자원부족 및 서비스 질 향상 등의 문제가 지적되어 왔다. 본 논문에서는 데이케어센터를 지역을 중심으로 접근하면서 그 발전방향을 논의하였다. 또한 전문가심층면접분석을 통해서 데이케어센터의 차후 비전을 제시하였다. 심층분석 결과로는 데이케어센터에서 제공하는 건강케어 프로그램은 지역사회의 문제 및 특성을 반영하여야 하고, 사용자 중심이어야 하며 지역통합적 방식을 취해야 함이 제시되었다.

Fast Millimeter-Wave Beam Training with Receive Beamforming

  • Kim, Joongheon;Molisch, Andreas F.
    • Journal of Communications and Networks
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    • 제16권5호
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    • pp.512-522
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    • 2014
  • This paper proposes fast millimeter-wave (mm-wave) beam training protocols with receive beamforming. Both IEEE standards and the academic literature have generally considered beam training protocols involving exhaustive search over all possible beam directions for both the beamforming initiator and responder. However, this operation requires a long time (and thus overhead) when the beamwidth is quite narrow such as for mm-wave beams ($1^{\circ}$ in the worst case). To alleviate this problem, we propose two types of adaptive beam training protocols for fixed and adaptive modulation, respectively, which take into account the unique propagation characteristics of millimeter waves. For fixed modulation, the proposed protocol allows for interactive beam training, stopping the search when a local maximum of the power angular spectrum is found that is sufficient to support the chosen modulation/coding scheme. We furthermore suggest approaches to prioritize certain directions determined from the propagation geometry, long-term statistics, etc. For adaptive modulation, the proposed protocol uses iterative multi-level beam training concepts for fast link configuration that provide an exhaustive search with significantly lower complexity. Our simulation results verify that the proposed protocol performs better than traditional exhaustive search in terms of the link configuration speed for mobile wireless service applications.