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In order to study the problem of short-term traffic prediction more effectively, experts and scholars have put forward various car-following models. Among data-driven algorithms, k-nearest neighbor algorithm is the most widely used due to its simplicity, flexibility and high accuracy. In this paper, the three-dimensional model based on improved knn algorithm is constructed. It transforms the input vector of basic knn algorithm into a three-row matrix. Data of three dimensions are considered, including only the previous moment data, short period of history data and long period of history data. Three-dimensional matrixes are constructed for prediction and similarity is measured by sum of 2-norm of 3 row vectors. Besides, weighted distance calculation method based on temporal distance is introduced to differentiate impacts data of different dimensions have on the results.

In Intelligent and Connected Transportation Systems (ICTS), vehicles, infrastructure, pedestrians exchange information through two-way telecommunication network. The system collects and uses multi-source data sufficiently so that control measures can be implemented in real-time. However, few studies have discussed how to achieve fairness based on dynamic priority. In this paper, the Platoon Dynamic Dispatching Model (PDDM), based on Vehicle-Intersection Coordination Scheme (VICS), is proposed to control vehicles. The first stage establishes the trajectory model and defines the conflict zones at the intersection. Platoons forms at the upstream, then the conflict risk indicator model is applied to predict the collision risk of the platoons. The dynamic priority dispatching model is applied to change the passing order of platoons at an intersection from all directions in real-time according to their status at the upstream. Finally, PDDM is solved by the wolf pack algorithm.

The general way to generate shifting schedule for a new developed vehicle is taking manual calibration way and doing test on the real vehicle that means a time-costing duty. Shift schedule auto-generation has been taken by more and more manufactures for its high efficiency. For auto-generation way, two groups of data set are important. The first is engine steady test data; and the other is drivability constraints defined by customers. Some useful results have been achieved in the field of passenger cars. But for off-road vehicle, there are some special requirements needed to consider, such as vehicle mass, 4WD function and etc. Four-wheel drive vehicles ask for more attraction for improving their performance considering their working in various driving environment. Automatic Transmission has been widely equipped in demanding off-road vehicles responding to the complex driving requirements for its advantage of easy operating.

With advantages of high efficiency and low cost, AMT (Automated Manual Transmission) has a very potential for auto-transmission, especially for heavy commercial vehicle, which has special requirements on low cost and easier operating. Recent years, some developments on multi-speed and electronic control, give us more confidence to consider AMT for heavy commercial vehicles, which offers a convenient and low cost way to multi-speed, and existed abundant gas resource for providing driven power. On the other hand, some technique issues challenge AMT in the application widely. For example, It is difficult to realize servo control for compressibility of gas. It therefore needs to find a way to realize the accurate control on auto-clutch operation system based on high quality system response. Accordingly, this work presents a system to realize hydraulic control powered with pneumatic power resource.

The shifting process always activates some changes of noise quality for its transient characteristics, especially for non-powered-shift transmissions, with which the power from engine is intermitted during the shifting period, such as Manual Transmission (MT) and Automated Manual Transmission (AMT). This type of noise change should have a very close relationship with the status of engine directly. But the essential reasons and how to estimate the noise have not been explored before. Therefore there is no clear understanding upon it and no formal methods yet described in the literature. The present study focuses on the phenomenon and makes effort to build reasonable research methods based on vehicles equipped with AMT. Furthermore, the metrics for assessing the noise has been developed with several different experiments and Support Vector Machines (SVMs) technique.

The reliability of a valve stem seal (VSS) is directly related to its ability to deliver the correct rate of lubrication. Too little lubrication may result in valve stem wear; too much may result in ‘burnt’ valves and seats. The correct operational envelope will therefore depend upon an engineer's ability to predict how parameters such as seal geometry and material properties change over the life of the seal. This paper discusses the use of accumulative leakage measurements to study the life performance of a VSS as changes are made to ‘key’ design sealing features. A standard design VSS is used for ‘normal’ leakage bench marking. The results are to be used in the development of predictive leakage models that use both close scrutiny leakage testing and continued lubrication theory development.