矩形顶管关键技术研究现状及发展趋势探讨

首先，对矩形顶管技术的发展历程及其国内外研究现状进行综述，介绍当前矩形顶管技术主要的应用场景，并结合顶推力预测、注浆减阻、背土效应演化机制和控制对策、顶进过程中的地层响应模式和沉降计算、工作面稳定性评估等关键技术问题，对矩形顶管的理论研究进展进行回顾和讨论。其次，根据矩形断面掘进机的结构形式和切削方式，对国内外矩形顶管掘进机的开发现状及其分类进行介绍。最后，归纳当前矩形顶管在装备及工程应用领域面临的技术挑战，探讨矩形顶管技术的发展趋势，对矩形顶管装备智能化，矩形曲线顶进，长距离、大断面及复合地层等复杂场景下的矩形顶管技术进行展望。     

Long-term impact of the Shinkansen on rail and air demand: analysis with data from Northeast Japan

This paper analyses how the high-speed rail construction in Northeast Japan (Tohoku) has affected total demand and interregional travel patterns. We use annual interregional passenger data from 1989 to 2012 and apply regression analysis with the demand between Tokyo and the Tohoku prefectures as the dependent variable. We distinguish particularly between the ‘Full-’ and the ‘Mini-’ Shinkansen, where the latter are branch services running with reduced speed. We find that the ‘Full-Shinkansen’ quickly increases rail and total public transport trips and generates additional rail demand year on year. The ‘Mini-Shinkansen’ impacts are less pronounced. Furthermore, our analysis shows that the Shinkansen has shifted some demand from air to rail once it started operation and increased rail share gradually. We therefore suggest that predictions of demand impacts should carefully distinguish immediate from gradual impacts. We also discuss differences in regional demand in that not all prefectures have gained equally from Shinkansen construction.     

Direct yaw moment control and power consumption of in-wheel motor vehicle in steady-state turning

Driving force distribution control is one of the characteristic performance aspects of in-wheel motor vehicles and various methods have been developed to control direct yaw moment while turning. However, while these controls significantly enhance vehicle dynamic performance, the additional power required to control vehicle motion still remains to be clarified. This paper constructed new formulae of the mechanism by which direct yaw moment alters the cornering resistance and mechanical power of all wheels based on a simple bicycle model, including the electric loss of the motors and the inverters. These formulation results were validated by an actual test vehicle equipped with in-wheel motors in steady-state turning. The validated theory was also applied to a comparison of several different driving force distribution mechanisms from the standpoint of innate mechanical power.     

Evaluation of expected maximum values of forces acting on containers and lashing rods on a container ship

The appearance of a number of large container ships in the 8000 TEU range raises the importance of a plan for container lashing arrangements on deck in relation to the design of the ship. Therefore, it is expected that a new method for evaluating the lashing arrangements on deck will be introduced which is applicable regardless of the ship's size and the lashing pattern, instead of using the standards of several different societies, as happens at present. To evaluate the lashing arrangements on deck, the expected maximum values of the forces acting on the containers and lashing rods should be evaluated. This paper presents a new method of evaluating the container lashing arrangements on a container ship using an "acceleration ellipsoid." The applicability of the acceleration ellipsoid to an evaluation of the expected maximum values of the forces was examined by comparing the expected maximum values of the forces calculated by the long-term distribution calculation known as the "Fukuda method," to those calculated using the acceleration ellipsoid. By comparing these results, it was confirmed that the expected maximum values of the forces calculated using the acceleration ellipsoid were not less than those calculated through by the long-term distribution calculation. It is concluded that the acceleration ellipsoid can be used to evaluate the expected maximum values of the forces acting on containers and lashing rods. Received: December 14, 2000 / Accepted: March 22, 2001     

Prediction of thermal environment via revision of PMV index with body temperature

PMV （Predicted Mean Vote） is a widely used index for evaluating the thermal environment. However, few studies have been conducted to take physiological values directly as evaluating indices. This paper assumes a linear relation between body temperature and both sweating rate and heat produced by shivering, and introduces the linear relation into the human heat balance equation to revise the classic PMV. And the assumption of linear relation is subsequently proved. The revised PMV possesses the same characteristic of dependent heat load as that of the classic one, and moreover it is convenient to be calculated.     

Estimation of left-turning vehicle maneuvers for the assessment of pedestrian safety at intersections

Improving pedestrian safety at intersections remains a critical issue. Although several types of safety countermeasures, such as reforming intersection layouts, have been implemented, methods have not yet been established to quantitatively evaluate the effects of these countermeasures before installation. One of the main issues in pedestrian safety is conflicts with turning vehicles. This study aims to develop an integrated model to represent the variations in the maneuvers of left-turners (left-hand traffic) at signalized intersections that dynamically considers the vehicle reaction to intersection geometry and crossing pedestrians. The proposed method consists of four empirically developed stochastic sub-models, including a path model, free-flow speed profile model, lag/gap acceptance model, and stopping/clearing speed profile model. Since safety assessment is the main objective driving the development of the proposed model, this study uses post-encroachment time (PET) and vehicle speed at the crosswalk as validation parameters. Preliminary validation results obtained by Monte Carlo simulation show that the proposed integrated model can realistically represent the variations in vehicle maneuvers as well as the distribution of PET and vehicle speeds at the crosswalk.     

Performance evaluation of the inside intersection median-turn lane markings on the mobility and safety performance of signalized intersections in the Philippines and Japan

Signalized intersections are one of the key elements that play a vital role at road networks. The efficiency and safety levels of intersections can affect the operational performance of the whole system. In general, turning traffic, especially median-turning, has always been considered as the most problematic movement in the operation of intersections. This becomes more critical with high turning demand where exclusive turning lanes (single or double) can be assigned to provide larger capacities for these movements and to reduce conflicts with through traffic. However, improper treatment of median-turn lanes could create cross-maneuvering behavior which may limit the expected increase in capacity and create safety issues. Median-turning lane markings are commonly provided at intersections in Japan to guide drivers while turning which is expected to reduce the conflicts among turning traffic. Meanwhile, in the Philippines, exclusive median-turn lanes are installed at intersections without proper treatment which may contribute to the low mobility and safety levels. Therefore, this study evaluated the impact of inside intersection lane markings on the operation of median-turn lanes in terms of mobility and safety. The vehicle maneuver, speed and interactions between the turning traffic were utilized as essential components for the assessment. The empirical analysis shows that conflicting trajectories were present on double turn lanes without median-turn lane markings in the Philippines, which resulted to serious conflicts among the turning vehicles and negatively influenced the turning speed and saturation flow rate of the turn lanes. On the other hand, the turn lane markings in Japan, provided a positive impact to mobility and safety of the turning lanes. Moreover, it was also found that the geometric characteristics and traffic signal phasing scheme highly affects the capacity and safety condition of signalized intersections.     

Fostering partnerships towards sustainable urban mobility from the national to local level: Matsuyama,Japan and Yogyakarta,Indonesia

This paper analyzes the implementation of Japan's and Indonesia's national frameworks aiming to promote sustainable urban mobility by placing transport policy coordination as pre-requisites under the decentralization regime. It takes two cities, Matsuyama and Yogyakarta, as the case studies. The analytical framework developed here highlights multi-level government coordination, coordination among local stakeholders, and regulator–operator coordination. The analysis is based on policy documents review, field observation, hearing and a questionnaire survey. The study shows some good practices as well as drawbacks of the schemes and produces lessons-learned from Japan's ‘omnibus town scheme’ to improve Indonesia's public transport program and for other cities in developing countries.     

A study on collision buffer characteristic of sharp entrance angle bow structure

SEA-Arrow (sharp entrance angle bow like an arrow) has no protrusion of the bulbous bow to reduce bow waves and has a transverse stiffening system in the narrow bow space to apply the buffer bow concept. This system has lower longitudinal stiffness than a conventional longitudinal stiffening system and therefore has buffer characteristic in ship-to-ship collision. A comparative collision study of SEA-Arrow and the conventional bulbous bow was conducted using elasto-plastic finite element analysis. A collision scenario where the striking ship hits the side shell of tanker midship perpendicularly was selected. The results showed that the buffer bow characteristic of SEA-Arrow is superior to that of the conventional bulbous bow, since much more energy is dissipated by the plastic deformation of striking and struck ships until the inner shell of struck ship ruptures.     

Dynamic control of a remotely operated vehicle using a neural network

The control of a remotely-operated underwater vehicle to maintain a prescribed depth in shallow water under irregular surface waves is realized through the application of the Robust Adaptive Neuro Controller, a composite control system incorporating—together with the conventional control algorithm—a neural network controller. This network bestows a learning capability on the system, allowing it to deal with unanticipated disturbances that would otherwise cause erroneous behavior of the vehicle. The effectiveness of this application is verified through mathematical simulation of a model vehicle's behavior, through experiment in a model basin, and through simulation of the behavior of an actual remotely operated vehicle in shallow water under irregular surface waves. Graphic data representing the learning process undergone by the neural network distinctly indicate the rising output from the network with the progression of learning, and the vehicle's depth variation traced in terms of the mean square error vividly show the diminution of deviation from the prescribed depth obtained with application of the neural network. Thus controlled to maintain constant depth, under-water vehicles with power supplied externally through a tether for propulsion and for heavy-duty operations should consolidate their advantage for such activities as maintenance of submarine structures and surveys in deep or hazardous water.