Evaluasi Kinerja Apill dan Geometrik Simpang 3 Sungai Bengkel Kota Bengkalis

Third junction of Sungai Bengkel was a Signalized Intersection which a hasn’t have traffic jam ,which has three approach, are North approach, West approach and East approach. However, the alinyemen for the North approach has problems that make it difficult for vehicles, especially four-wheelers to turn because the effect bottle neck resulting in the slow motion of the vehicle and change of phase time . the problem solving, the evalution of traffic light and intersection geometry were carried out by widening the alinyemen for the North approach and East approaches and doing changes in cycle time. The purpose of evaluating the performance of traffic light and Geometrics at the third intersection of Sungai Bengkel is to determine the value of the degree of saturation and to know the performance of the intersection.At the intersection planning, it refers to the PKJI 2014 for Intersection Performance, while for the Geometrics it refers to Module 4 of the Ministry of Public Works and Public Housing on Geometric Planning of Plane Intersections.Based on the calculation results of the Sungai Bengkel junction performance indicate that, the degree of saturation < 0.85,which is 0.529 for North, 0.537 for East, and 0.570 for West .With the radius is 15 m, and the cycle time of traffic light 50 second, with the delay time as long as 17 second/pcu

Intersection Sight Distance Characteristics of Turbo Roundabouts

A turbo roundabout uses spiral circulatory roads for effectively counteracting the problems faced in modern multilane roundabouts. First developed in 1996, the turbo roundabout has an advantage over the conventional roundabout regarding capacity and safety. Turbo roundabouts are still in the developing phase in North America, but even in the European subcontinent where they exist in large numbers, reliable analytical studies on the critical parameters of roundabout visibility are lacking. Visibility (sight distance) helps to shape the geometry of the intersection and aids in safety. This paper presents the mathematical characteristics of the intersection geometry and intersection sight distance (ISD) of the turbo roundabout. Mathematical formulas are presented for the sight distance from the approaching vehicle to the conflicting-entering and circulating vehicles. The maximum lateral clearances to the conflicting vehicles are derived using mathematical optimization. The developed analytical method is verified graphically using AutoCAD. To assist in practical applications, design aids for the maximum lateral clearance are presented. The presented method and design aids should aid in promoting safety at turbo roundabouts.

DEM ACCURACY RESEARCH BASED ON UNMANNED AERIAL SURVEY DATA

Currently, digital elevation models (DEM) created by photogrammetric method based on unmanned aerial survey data are becoming an increasingly popular product. They are used in various areas of human activity related to modelling and analysis of terrain, namely: topography, engineering and geodetic surveys, surveying, archaeology, geomorphology, etc. The accuracy of digital surface and terrain models obtained by the photogrammetric method depends on the accuracy of aerial triangulation and dense point cloud from a number of overlapping images. In turn, the accuracy of the aerial triangulation is determined by the accuracy of the measurements of the tie points, GCP's / check points and the intersection geometry. When constructing a dense cloud using the SGM algorithm, the quality of the surface/terrain model depends not only on the accuracy of point identification, but also on filtering outliers and rejecting unreliable measurements. This article presents the results of evaluating the accuracy of creating a digital elevation model obtained by various unmanned aerial survey systems on a single test area.

A Method for Determining the Capacity of an Exclusive Left Lane with a Permitted Phase under Nonstrict Priority

A new method has been developed for estimating the capacity of an exclusive left lane with a permitted phase under nonstrict priority. Different from maneuvers under strict priority, these left-turning vehicles were released in the form of a left-turn group. A field survey was first conducted to explore the maximum number of vehicles in a left-turn group, and the releasing process of the permitted left turns. The observations revealed that (1) the maximum number is related to the intersection geometry and (2) the releasing process includes two stages: the first left-turn group crossing at the beginning of a permitted phase and the following left-turn groups crossing using gaps provided by opposing right turns. Next, a method based on probability theory and these observation results were applied to estimate the capacity of an exclusive left lane. The procedure contains two stages and eight steps. Finally, the estimation of the left-turn capacity using the proposed model was validated by comparing the capacity from the strict priority and actual maximum volumes.

Peer-to-Peer Priority Signal Control Strategy in a Connected Vehicle Environment

This paper presents a methodology that enhances the priority signal control model in the multi-modal intelligent traffic signal system (MMITSS). To overcome the range limit of vehicle to infrastructure (V2I) and the intersection geometry message (MAP) distance limits, peer-to-peer intersection communications are utilized to send priority requests from adjacent intersections. Through integrated communication, the peer priority control strategy can create a signal plan for prioritized vehicles that considers longer term (headway) arrival times. Transit vehicles are considered in this study. The longer-term signal plan provides a flexible signal schedule that allows local phase actuation. The peer priority strategy is effective in reducing the number of stops and delay for priority eligible vehicles, while minimizing the negative impact on regular vehicles. To validate the strategy, a simulation experiment was designed to compare fully actuated control, coordination, and MMITSS priority control using two different VISSIM simulation networks (Arizona and Utah). The result shows that the peer-to-peer long term planning strategy can improve transit service reliability while limiting the adverse impact on other traffic.

Cargo navigation across 3D microtubule intersections

The eukaryotic cell’s microtubule cytoskeleton is a complex 3D filament network. Microtubules cross at a wide variety of separation distances and angles. Prior studies in vivo and in vitro suggest that cargo transport is affected by intersection geometry. However, geometric complexity is not yet widely appreciated as a regulatory factor in its own right, and mechanisms that underlie this mode of regulation are not well understood. We have used our recently reported 3D microtubule manipulation system to build filament crossings de novo in a purified in vitro environment and used them to assay kinesin-1–driven model cargo navigation. We found that 3D microtubule network geometry indeed significantly influences cargo routing, and in particular that it is possible to bias a cargo to pass or switch just by changing either filament spacing or angle. Furthermore, we captured our experimental results in a model which accounts for full 3D geometry, stochastic motion of the cargo and associated motors, as well as motor force production and force-dependent behavior. We used a combination of experimental and theoretical analysis to establish the detailed mechanisms underlying cargo navigation at microtubule crossings.

PRECISION ANALYSIS OF VISUAL ODOMETRY BASED ON DISPARITY CHANGING

This thesis aims to analyze the precision of Position and orientation of cameras on Mobile Mapping System (MMS) determined by disparity based VO (DBVO). Dual forwards taken cameras on MMS are applied to obtain a sequence of stereo pairs. The Interior Orientation Parameters (IOPs) and Relative Orientation Parameters (ROPs) are derived in advance. The pose estimation is achieved by DBVO without additional control data. The procedure of DBVO consists of four steps. First up, keypoint detection and matching is conducted to obtain tie points in consecutive images. Then, image rectification is implemented to transform tie points into epipolar image space. Next, parallax equation is applied to estimate the 3D coordinates of interest points in epipolar image 3D space. Since their image points have different disparity in neighboring stereo pairs, the 3D coordinates of interest points in neighboring pairs are different as well. Finally, 3D conformal transformation is employed to derive the transformation parameters between neighboring pairs according to changing of coordinates of interest points. The posteriori STDs are adopted to assess the quality of transformation. Besides, check data of ground trajectory derived by photo triangulation are applied to evaluate the result. The relative errors of horizontal and vertical translations derived by DBVO are 2&amp;thinsp;% and 3&amp;thinsp;% in non-viewing direction. However, the translation in viewing direction and three rotation angles derived by DBVO have significant systematic errors about 1&amp;thinsp;m, 3°, 3° and 10° respectively. The influence of error propagation is not significant according to the chart of error distance ratio. In open area, the trajectory of INS/GPS is similar to ground truth, while the trajectory derived by DBVO has 44&amp;thinsp;% relative error. In residential district, the trajectory derived by INS/GPS has drift error about 2&amp;thinsp;m, while the relative error of the trajectory derived by DBVO decreases to 38&amp;thinsp;%. It is presumed that the systematic error results from 3D coordinates estimated by parallax equation because of poor intersection geometry. It will be proved by adding sideward photographing cameras in the future.

Kinesin-12 motors cooperate to suppress microtubule catastrophes and drive the formation of parallel microtubule bundles

Human Kinesin-12 (hKif15) plays a crucial role in assembly and maintenance of the mitotic spindle. These functions of hKif15 are partially redundant with Kinesin-5 (Eg5), which can cross-link and drive the extensile sliding of antiparallel microtubules. Although both motors are known to be tetramers, the functional properties of hKif15 are less well understood. Here we reveal how single or multiple Kif15 motors can cross-link, transport, and focus the plus-ends of intersecting microtubules. During transport, Kif15 motors step simultaneously along both microtubules with relative microtubule transport driven by a velocity differential between motor domain pairs. Remarkably, this differential is affected by the underlying intersection geometry: the differential is low on parallel and extreme on antiparallel microtubules where one motor domain pair becomes immobile. As a result, when intersecting microtubules are antiparallel, canonical transport of one microtubule along the other is allowed because one motor is firmly attached to one microtubule while it is stepping on the other. When intersecting microtubules are parallel, however, Kif15 motors can drive (biased) parallel sliding because the motor simultaneously steps on both microtubules that it cross-links. These microtubule rearrangements will focus microtubule plus-ends and finally lead to the formation of parallel bundles. At the same time, Kif15 motors cooperate to suppress catastrophe events at polymerizing microtubule plus-ends, raising the possibility that Kif15 motors may synchronize the dynamics of bundles that they have assembled. Thus, Kif15 is adapted to operate on parallel microtubule substrates, a property that clearly distinguishes it from the other tetrameric spindle motor, Eg5.