• Title/Summary/Keyword: Longitudinal Slope

Search Result 144, Processing Time 0.028 seconds

Estimation of Stream Geomorphological Characteristics Based on the Informational Entropy (정보엔트로피 개념에 의한 하천 지형특성인자의 산정)

  • Jeon, Min-Woo;Lee, Dae-Gyu
    • Journal of Wetlands Research
    • /
    • v.11 no.2
    • /
    • pp.89-98
    • /
    • 2009
  • This study determines the stream mean slope, stream slope and longitudinal stream profile based on the concept of informational entropy. Maximizing the entropy will make the probability distribution of longitudinal stream profile as uniform as possible while satisfying the constraints. Using this relationships the mean stream slope, stream slope and longitudinal stream profile formulas were derived. The parameters of the applied streams were estimated by the least square method using the geomorphological factors of Dalchon stream basin obtained from Chungcheong Buk-Do local stream consolidation scheme drawings. The comparative investigation was performed between the observed and simulated mean stream slope and longitudinal stream profile, and are in good agreement with the measured data. It is noted that this results can be used in the estimation of stream mean slope and longitudinal stream profile.

  • PDF

Longitudinal mediation effect of mathematics class factors between goal perception and mathematics academic achievement on middle school students (중학생들의 목표인식과 수학학업성취도 관계에 대한 수학수업요인의 종단매개효과)

  • Jung, Hee Sun
    • The Mathematical Education
    • /
    • v.58 no.1
    • /
    • pp.21-39
    • /
    • 2019
  • This study examines the longitudinal effect of goal perception, mathematics class factors(perceptions about mathematics teachers (PMT), mathematics classroom attitude), and mathematics academic achievement. This study consists of three research models. First, we examined the longitudinal change of goal perception, perceptions about mathematics teachers (PMT), mathematics classroom attitude, and mathematics academic achievement using latent growth curve modeling. Secondly, the slope of PMT is a critical mediator between the slope of goal perception and the slope of mathematics academic achievement. Finally, the slope of mathematics classroom attitude is a critical mediator between the slope of goal perception and the slope of mathematics academic achievement. Data were extracted from Seoul Education Longitudinal Study from 2010 to 2012 (in three waves), and the analysis used by middle school students, measured by 4163 students of the three-wave surveys. Latent growth modeling was applied to verify the research problems. The results of the research are as follows. First, the slope of goal perception had positive and significant effects on the slope of PMT and mathematics classroom attitude, respectively. Second, the slope of PMT and mathematics classroom attitude had positively significant effects on the slope of mathematics academic achievement. Finally, it was confirmed that the slopes of PMT and mathematics classroom attitude are critical mediators between the slope of goal perception and the slope of mathematics academic achievement.

Applicability Evaluation of PSC-U Type Girder and Precast Deck to the Vertical Curves in Urban Maglev Train Route (도심형 자기부상열차 선로 종곡선 구간에서의 PSC-U 형 거더와 프리캐스트 바닥판 적용성 평가)

  • Jin, Byeong-Moo;Kim, In-Gyu;Kim, Young-Jin;Lee, Yun-Seok;Ma, Hyang-Wook;Oh, Hyun-Chul
    • Proceedings of the KSR Conference
    • /
    • 2008.06a
    • /
    • pp.24-30
    • /
    • 2008
  • One of the characteristics of the Maglev Train is the prominent capability of upgoing. Maglev train with the aim of longitudinal slope 7/100 is under development by the Center for Urban Maglev Program in Korea. To realize these slope, vertical curves must be inserted before and after the slope. The inserted curve has the radius of 3,000m generally. The insertion of these vertical curve results in the additional differences between the girder upper face and the guide rail, and the alignments are controlled by cast in place concrete at present. In this study, for longitudinal curved route with longitudinal slope 6/100, the applicability of PSC-U type girder and precast deck was evaluated for the span length 25m, 30m and vertical curve radii with 3,000m and 1,500m with respect to longitudinal slope 6/100.

  • PDF

Research on Longitudinal Slope Estimation Using Digital Elevation Model (수치표고모델 정보를 활용한 도로 종단경사 산출 연구)

  • Han, Yohee;Jung, Yeonghun;Chun, Uibum;Kim, Youngchan;Park, Shin Hyoung
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.20 no.6
    • /
    • pp.84-99
    • /
    • 2021
  • As the micro-mobility market grows, the demand for route guidance, that includes uphill information as well, is increasing. Since the climbing angle depends on the electric motor uesed, it is necessary to establish an uphill road DB according to the threshold standard. Although road alignment information is a very important element in the basic information of the roads, there is no information currently on the longitudinal slope in the road digital map. The High Definition(HD) map which is being built as a preparation for the era of autonomous vehicles has the altitude value, unlike the existing standard node link system. However, the HD map is very insufficient because it has the altitude value only for some sections of the road network. This paper, hence, intends to propose a method to generate the road longitudinal slope using currently available data. We developed a method of computing the longitudinal slope by combining the digital elevation model and the standard link system. After creating an altitude at the road link point divided by 4m based on the Seoul road network, we calculated individual slope per unit distance of the road. After designating a representative slope for each road link, we have extracted the very steep road that cannot be climbed with personal mobility and the slippery roads that cannot be used during heavy snowfall. We additionally described errors in the altitude values due to surrounding terrain and the issues related to the slope calculation method. In the future, we expect that the road longitudinal slope information will be used as basic data that can be used for various convergence analyses.

Experimental study on the influence of the ground surface slope on the longitudinal load transfer in shallow tunnel (얕은 터널에서 지표경사가 종방향 하중전이에 미치는 영향에 대한 실험적 연구)

  • Yim, Il Jae;Lee, Sang Duk
    • Journal of Korean Tunnelling and Underground Space Association
    • /
    • v.19 no.6
    • /
    • pp.887-903
    • /
    • 2017
  • Lots of shallow tunnels are constructed in the mountainous areas where the stress distribution in the ground around tunnel is not simple, also the impact of stress conditions on the longitudinal load transfer characteristics is unclear. The tunnel construction methods and the ground conditions would also affect the longitudinal load transfer characteristics which would be dependant on the displacement patterns of tunnel face. Therefore, in this study, the slope of the ground surface was varied in $0^{\circ}$, $10^{\circ}$, $20^{\circ}$, $30^{\circ}$, and the longitudinal load transfer depended on the deformation conditions of tunnelface (that were maximum deformation on the top, constant deformation, and maximum deformation on the bottom), and the stress distribution at tunnelface. As results, when the tunnelface deformed, the earth presure on the tunnelface decreased and the load at tunnel crown increased. The load transferred on the crown was influenced by the earth presure on tunnel face. Smaller load would be transfered to the wide areas when the slope of ground surface decreased. When the slope of ground surface became larger, the longitudinal load transfer would be smaller and would be concentrated on tunnelface, In addition, the shape of the transferred load distribution in the longitudinal direction was dependant on the deformation shape of tunnelface. The deformation shape of tunnelface and stress conditions in longitudinal sections would affect the shape and the magnitude of the load transfer in the longitudinal directions.

Autonomous Driving Acceleration Estimation Model According to the Slope of the Road (도로의 경사도에 따른 자율주행 가속도 추정 모델)

  • Park, KyeoungWook;Heo, Myungseon;Oh, Youngchul;Han, Jihyeong;Jeong, HwaHyen;You, Byungyong
    • IEMEK Journal of Embedded Systems and Applications
    • /
    • v.16 no.6
    • /
    • pp.285-292
    • /
    • 2021
  • Autonomous vehicles are divided into an upper controller that calculates control value through cognitive judgment and a lower controller that appropriately transmits its control value to an actuator. Here, the longitudinal control in a lower controller has a problem as the road slopes due to the property of the Acceleration sensor to output the acceleration as the slope of the device. Therefore, in this paper, a sigmoid function is proposed to determine the slope to compensate for this problem. Through the experiment, Checked performance by comparing the existing table model with the proposed model.

Evaluation of Slope Failure Possibility on Forest Road Using Fuzzy Theory(I) - On the Fill Slope of the Metamorphic Rock Area - (Fuzzy이론(理論)을 이용(利用)한 임도사면(林道斜面)의 붕괴가능성(崩壞可能性) 평가(評價)(I) - 변성암지역(變成岩地域)의 성토사면(盛土斜面)을 중심(中心)으로 -)

  • Cha, Du Song;Ji, Byoung Yun;Oh, Jae Heun
    • Journal of Korean Society of Forest Science
    • /
    • v.89 no.1
    • /
    • pp.33-40
    • /
    • 2000
  • This study was carried out to evaluate the fill slope failure possibility of forest road in Metamorphic rock area using fuzzy theory which is non-linear model. The results were summarized as follows. The potential slope failure by nine factors was mainly occurred under the such conditions as the total road width ranging from 4m to 5m, longitudinal gradients below $2^{\circ}$, fill slope length greater than 8m, fill slope gradients steeper than $40^{\circ}$, road on ridge position, soil types with weathered rock, slope gradients steeper than $40^{\circ}$, aspect of NW, and longitudinal slope form in convexity. The weight of importance by factors on fill slope failure was ranked in the order of fill slope length, fill slope gradient, road position, soil type, aspect and longitudinal slope form. The analysis showed that the fill slope failure possibility was low with less than 0.485 of the fuzzy integral value and high with more than 0.620 of the value. And the discriminant accuracy was 74.6%. The analysis with six out of nine factors indicated that the possibility was low with less than 0.441 of the fuzzy integral value and high with more than 0.583 of the value. In this case, the discriminant accuracy was slightly increased to 78.0%.

  • PDF

Charateristics of the Jointed Steel-Grid Reinforcement and the Application (결합강그리드보강재의 특성 및 적용)

  • Han, Jung-Geun
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.5 no.3
    • /
    • pp.15-22
    • /
    • 2002
  • To analysis of the embanked slope stability using a jointed reinforcement, the internal stability and the external stability have to be satisfied, respectively. But, because the lengths of ready-made steel-grid were limited, the reinforcements must be connecting themselves to the reinforcing. In this study, the mechanical test was carried out to investigate the tensile failure and the pullout failure at the joint parts of them, which was based on the analysis of reinforced slope in field. Through the tensile tests in mid-air for the jointed steel-grid, the deformation behavior was seriously observed as follows : deformation of longitudinal member, plastic deformation of longitudinal member and of crank part. Those effects were due to the confining pressure and overburden pressure of the surrounding ground. The bearing resistance at jointed part of jointed steel-grid was due to the latter only. The maximum tensile forces were higher about 20kN~27kN than ultimate pullout resistance, but, the results of those was almost the same in mid-soil. The failures of steel-grid occurred at welded point both of longitudinal members and transverse members and of jointed parts. The strength of jointed parts itself got pullout force about 20kN, which was about 65% for ultimate pullout force of the longitudinal members N=2. To the stability analysis of reinforced structure including the reinforced slope, the studying of connection effects at jointed part of reinforcement members must be considered. Through the results of them, the stability of reinforced structures should be satisfied.

Stereo-Vision Based Road Slope Estimation and Free Space Detection on Road (스테레오비전 기반의 도로의 기울기 추정과 자유주행공간 검출)

  • Lee, Ki-Yong;Lee, Joon-Woong
    • Journal of Institute of Control, Robotics and Systems
    • /
    • v.17 no.3
    • /
    • pp.199-205
    • /
    • 2011
  • This paper presents an algorithm capable of detecting free space for the autonomous vehicle navigation. The algorithm consists of two main steps: 1) estimation of longitudinal profile of road, 2) detection of free space. The estimation of longitudinal profile of road is detection of v-line in v-disparity image which is corresponded to road slope, using v-disparity image and hough transform, Dijkstra algorithm. To detect free space, we detect u-line in u-disparity image which is a boundary line between free space and obstacle's region, using u-disparity image and dynamic programming. Free space is decided by detected v-line and u-line. The proposed algorithm is proven to be successful through experiments under various traffic scenarios.

A Monte-Carlo method and Boltzmann Equation analysis on the electron swarm parameter in SiH$_4$+Ar mixtures gas. ($SiH_4+Ar$ 혼합기체의 전자군 파라미터에 대한 볼츠만 방정식 및 몬테 칼로법 해석)

  • 김대연;하성철
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 1999.05a
    • /
    • pp.387-390
    • /
    • 1999
  • Electron swarm parameterdthe drift velocity and longitudinal diffusion coefficienthn $SiH_4-Ar$ mixtures containing 0.5% and 5% monosilane were measured using over the range of E/N from 0.01 to 300 Td at room temperature. Electron swarm parameters in argon were drastically changed by adding a small amount of monosilane. The electron drift velocity in both mixtures showed unusual behaviour against E/N. It had negative slope in the medium range of E/N, yet the slope was not smooth but contained a small hump. The longitudinal diffusion coefficient also showed a corresponding feature in its dependence on E/N. A two-tern approximation of the Boltzmann equation analysis and Monte Carlo simulation have been used to study electron transport coefficients.

  • PDF