The 2008 New Zealand public transport management act: Rationale, key provisions, and parallels with the United Kingdom

In January 2009, following a lengthy industry review and consultation process, the New Zealand Public Transport Management Act (PTMA) came into force. The Act allows Regional Transport Authorities, as the primary procurers of public transport services, to place either a control or a contracting requirement upon services that are registered as commercial requiring no subsidy. The imposition of either the control or the contracting requirement is designed to facilitate greater system integration, improve service continuity and enhance services to the customer, andallow the Authority to invest in key strategic projects, such as integrated fares and ticketing, so as to grow patronage.The PTMA’s other objective is to ensure improved value for public subsidies. Recent years have seen significant subsidy inflation for seemingly little commensurate benefits. The Act will allow the Regional Transport Authority to achieve greater value for money through improved farebox, a shift to longer, larger contracts to increase competition in the market, a more appropriate allocation of risk, and the removal of the ability of operators to ‘game’ the current system by using strategically placed commercial services as barriers to competition.Similar concerns have also stimulated new legislation in the UK and this paper illustrates the parallels in the environment and proposed response.     

Tex13基因非放射性原位杂交探针的制备

目的研究制备地高辛(DIG)标记的Tex13(testis expressed gene 13)基因非放射性原位杂交探针,用于检测小鼠性腺Tex13基因的表达。方法采用RT-PCR方法扩增Tex13靶序列,将其插入带SP6和T7 RNA聚合酶启动子的pGEM-T Easy质粒,转入大肠杆菌DH10B,经蓝白斑筛选获得重组质粒,用T7和SP6引物对重组质粒进行PCR扩增,以此PCR产物为模板,以DIG RNA Labeling Mix为底物,经SP6 RNA聚合酶和T7 RNA聚合酶体外转录,分别制备DIG标记的反义链和正义链RNA探针。结果应用正常小鼠睾丸组织非放射性原位杂交实验,证实制备的探针具有较高的特异性和敏感性。结论 DIG标记Tex13基因杂交探针的成功制备,为进一步研究Tex13基因在小鼠性腺中的表达定位和发育规律以及它在减数分裂过程中的作用提供了实验基础。     

Controller design for soft-disability remedy of the electric power steering system

The electric power steering (EPS) system is designed to reduce the effort exerted by driver on the steering wheel. One of the most common and critical failures of EPS is the soft-disability of the torque sensor or the loss of its signal, which leads to the instant shutdown of the EPS system while turning and causes serious traffic accidents. In this paper, a novel controller based on the self-alignment torque (SAT) estimation was designed to remedy the soft-disability of EPS system. After the SAT estimation method was verified by the empirical Magic Formula (MF) tire model, the remedy control strategy based on the SAT estimation was developed and evaluated by simulations under step and sinusoidal inputs. To further evaluate the performance of the controller on a real vehicle, experiments on a real EPS system were implemented under step and sinusoidal inputs. The results of simulation and experiment using the controller based on estimated SAT showed this controller to be feasible and capable of eliminating the abrupt reaction torque increment caused by shutdown of EPS and of remedying the soft-disability of EPS system under common input signals.     

Design of an energy management strategy for parallel hybrid electric vehicles using a logic threshold and instantaneous optimization method

A novel parallel hybrid electric vehicle (PHEV) configuration consisting of an extra one-way clutch and an automatic mechanical transmission (AMT) is taken as the study subject of this paper. An energy management strategy (EMS) combining a logic threshold approach and an instantaneous optimization algorithm is developed for the investigated PHEV. The objective of this EMS is to achieve acceptable vehicle performance and drivability requirements while simultaneously maximizing engine fuel economy and maintaining the battery state of charge (SOC) in its rational operation range at all times. Under the MATLAB/Simulink environment, a computer simulation model of the studied PHEV is established using the bench test results. Simulation results for the behavior of the engine, motor, and battery illustrate the potential of the proposed control strategy in terms of fuel economy and in keeping the deviations of SOC at a low level.     

Sensor fusion-based lane detection for LKS+ACC system

This paper discusses the market trends and advantages of a safety system integrating LKS (Lane Keeping System) and ACC (Adaptive Cruise Control), referred to as the LKS+ACC system, and proposes a method utilizing the range data from ACC for the sake of lane detection. The overall structure of lane detection is the same as the conventional method using monocular vision: EDF (Edge Distribution Function)-based initialization, sub-ROI (Region Of Interest) for left/right and distance-based layers, steerable filter-based feature extraction, and model fitting in each sub-ROI. The proposed method adds only the system for confining lane detection ROI to free space that is established by range data. Experimental results indicate that such a simple adaptive ROI can overcome occlusion of lane markings and disturbance of neighboring vehicles.     

Driving environment assessment using fusion of in- and out-of-vehicle vision systems

Because the overall driving environment consists of a complex combination of the traffic Environment, Vehicle, and Driver (EVD), Advanced Driver Assistance Systems (ADAS) must consider not only events from each component of the EVD but also the interactions between them. Although previous researchers focused on the fusion of the states from the EVD (EVD states), they estimated and fused the simple EVD states for a single function system such as the lane change intent analysis. To overcome the current limitations, first, this paper defines the EVD states as driver’s gazing region, time to lane crossing, and time to collision. These states are estimated by enhanced detection and tracking methods from in- and out-of-vehicle vision systems. Second, it proposes a long-term prediction method of the EVD states using a time delayed neural network to fuse these states and a fuzzy inference system to assess the driving situation. When tested with real driving data, our system reduced false environment assessments and provided accurate lane departure, vehicle collision, and visual inattention warning signals.     

Physical-chemical properties of ethanol-diesel blend fuel and its effect on the performance and emissions of a turbocharged diesel engine

This paper deals with the main physical-chemical properties of ethanol-diesel blend and the effects of ethanoldiesel blends (up to 15% volume) on engine performance (full load torque vs. engine speed, BSEC vs. torque at 1400 r/min and 2300 r/min, and effect of start of injection angle) and emissions in ECE R49 tests (steady 13 points) using a 6.6 L inline 6-cylinder turbocharged direct injection diesel engine. The results show that an increase in ethanol fraction results in decreased viscosity of the blend fuel and very high distillation characteristics in the low temperature range. Solvents can improve the solubility of ethanol-diesel blends. The engine power was degraded proportional to the ethanol content (10% and 15%) due to the LHV (low heating value) of the blends. The higher latent heat of vaporization and lower CN (cetane number) of ethanol, which results from the steady state emissions of CO, HC, and SOF (soluble organic fraction), were much higher in the ECE R49 tests at low loads. Soot (solid mass) emissions were improved. The particulate matter emissions were significantly increased with higher blend volumes, and NOx emissions slightly increased with higher ethanol volumes. By increasing the injection angle properly, the performance parameters of the diesel engine were improved, but NOx emissions were deteriorated slightly.     

Research on the electro-hydraulic variable valve actuation system based on a three-way proportional reducing valve

As the internal combustion engine moves into the 21st century, fully flexible valve actuation systems are being proposed as an enabling technology for advanced internal combustion engine concepts. Electro-hydraulic valve actuator systems are being considered as a potential variable valve technology. Compared to the servo control system, the system using a proportional valve has the advantages of low price, high anti-pollution ability and high reliability. Our research focuses on exploring the dynamic characteristic of the electro-hydraulic variable valve system, which is based on three-way proportional reducing valve. In this paper, the structure and working principles of the system are described. The dynamic mathematical model of the system is derived. From the analysis of a linearized model and dynamic simulation, it is demonstrated that the system will be stable only if the proportional reducing valve has a positive opening. Some structural factors that affect the system’s dynamic characteristics, such as input signal, the stiffness of the return spring and the pre-tightening force of the return spring, are studied using AMESim. The experimental results coincide with the theoretical and simulated analyses. Further study shows that the dynamic response can be improved effectively by adopting closed-loop control of valve lift.     

Interior sound field refinement of a passenger car using modified panel acoustic contribution analysis

Panel acoustic contribution analysis (PACA) is a practical engineering tool for the reduction of interior structure-borne noise in passenger cars. In this study, the current PACA method has been improved for sound field refinement of the entire interior. Two new parameters, the “acoustic contribution sum” and the “total sound field contribution”, are introduced to analyze the interior sound field characterized with multiple field points and sound pressure peaks, and to evaluate the integrated acoustic contributions of auto body panels. In addition, a systematic methodology for automotive interior sound field refinement is also proposed on the basis of the modified PACA method. An example of a passenger car model demonstrates the application of the sound-field-refinement methodology and shows the advantage of using damping layers at optimum locations on the auto body. The example also shows that the modified PACA method has practical significance for refining the interior sound field and decreasing added mass in accord with the trend towards lightweight auto bodies.     

Motor control of input-split hybrid electric vehicles

A motor control strategy for an input-split hybrid electric vehicle (HEV) is proposed. From a power characteristic analysis, it is found that the powertrain efficiency decreases for speed ratios at which power circulation occurs. Using dynamic models of an input-split HEV powertrain, a motor-generator control algorithm for obtaining high system efficiency is designed by inversion-based control. The performance of the control algorithm is evaluated by the simulator which is developed based on PSAT, and simulation results are compared with the test results. It is found that, even if the engine thermal efficiency is sacrificed by moving the engine operation point from the OOL for the control strategy, improved overall powertrain system efficiency can be achieved by the engine operation that gives a relatively high efficiency from the viewpoint of the overall powertrain efficiency. The control algorithm developed can be used in design of future electric vehicles.