The paper begins by reviewing what is known about route choice processes and notes the mismatch between this knowledge and the route choice assumptions embedded in the most widely used assignment models. Empirical evi...
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The paper begins by reviewing what is known about route choice processes and notes the mismatch between this knowledge and the route choice assumptions embedded in the most widely used assignment models. Empirical evidence on the influence of route guidance advice on route choice is reviewed and, despite its limited nature, is seen to suggest that users are reluctant to follow advice unless they find it convincing and that, the more familiar they are with the network, the less likely they are to accept advice. Typically only a small minority of journeys are made in total compliance with advice. Results from an interactive route choice simulator (IGOR) are summarised and are seen to reveal that compliance depends on the extent to which the advice is corroborated by other factors, on the drivers' familiarity with the network and on the quality of advice previously received. It is noted that the IGOR results are in a form which would enable response models to be calibrated. Recent approaches to the modelling of route choice in the context of guidance are discussed. Some are seen to make simplifying assumptions which must limit the relevance of their results;most make no allowance for the fact that drivers are unlikely to comply with all advice and several are not able to represent the benefits which guidance might bring in the context of sporadic congestion or incidents. As an alternative, a two phase model comprising a medium term strategic equilibrium and a day-specific simulation with explicit representation of driver response is proposed.
Automated guidance Vehicles' guidance techniques, make use, in most vehicles, of a painted strip or a cable buried in the floor. Free ranging vehicles are now also available in limited types but at prohibitive cos...
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The problem of path keeping of marine vehicles along curved paths is considered. In particular, we are concerned with circular arcs that join two consecutive straight line segments. This provides smooth path changes b...
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The problem of path keeping of marine vehicles along curved paths is considered. In particular, we are concerned with circular arcs that join two consecutive straight line segments. This provides smooth path changes between one segment and the next utilizing a purely geometric reference path construction. Pure pursuit guidance is coupled with orientation angle control law to ensure stability and accuracy. Sensitivity analysis with respect to inaccuracies in the knowledge of the vehicle hydrodynamic characteristics is performed. The results demonstrate the validity of this approach and offer a way to achieve accurate path keeping in confined spaces.
The atmospheric flight of a spacecraft is considered when a aeroassisted orbit change maneuver is performed. Both guidance and control problems are solved and make respectively use of nonlinear control theory and clas...
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The atmospheric flight of a spacecraft is considered when a aeroassisted orbit change maneuver is performed. Both guidance and control problems are solved and make respectively use of nonlinear control theory and classical adaptive control schemes. The originality of the work lies in the consideration of the overall guidance and control problem. A second point which is worth to be noticed is that focus is set on computational time. Whereas gain scheduling is known to be compatible with limited computing power, the main stream in literature consists in implementing some optimizing routines when the guidance problem is tackled. This scheme is dramatically time consuming and is deliberately skipped in the paper; it is replaced by a trajectory tracking guidance policy issued from modem nonlinear control theory. The guidance and control solution is shown to be quite unsensitive to atmospheric density deviations which constitute major unknown parameters in the higher layers of the atmosphere.
Guided bus is a transport concept which ought more properly to be termed `guidable bus', because its essential characteristic is that the vehicles can operate steered on ordinary roads in the normal manner or can ...
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Guided bus is a transport concept which ought more properly to be termed `guidable bus', because its essential characteristic is that the vehicles can operate steered on ordinary roads in the normal manner or can be guided wherever infrastructure is provided for this purpose. Guided bus is intended to bring together the best features of road and rail transport to provide a high-performance, highly reliable system offering origin-destination transport for the majority of users, in today's idiom, genuinely a seamless rapid transit system. Compared to ordinary busways, guided busways offer the opportunity for substantial reductions in the amount of space required and provide an enhanced ride and performance. Buses can be guided electronically or mechanically;although research on the current generation of guided buses started with electronic guidance, the greatest success has been achieved with mechanical guidance. In particular, the concept of kerb-guidance where the vehicle is steered by two 180 mm dia. solid rubber wheels in a bus lane provided with 180 mm high kerbs set 2.6 m apart, has achieved greatest provenance with over 12 years of continuous operational use. Because guidance need only be provided where congestion or circuitous road networks would otherwise delay buses the design of any system needs to explore localized opportunities as well as the overall system performance. Introduction can be incremental, as funds allow and needs require. The operational design implications for a guided bus system therefore are that great care needs to be taken in the application of a broad range of design features in a wide variety of potential applications to achieve the most cost-effective and efficient rapid transit system.
A fast, inexpensive, and versatile technique for patterning the surface of glass coverslips with molecules of biological interest is described. The technique combines photolithographic, silane-coupling, and protein ad...
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A fast, inexpensive, and versatile technique for patterning the surface of glass coverslips with molecules of biological interest is described. The technique combines photolithographic, silane-coupling, and protein adsorption procedures to pattern coverslips with amines, alkanes, and proteins with micrometer spatial resolution. The attachment of amines and alkanes was verified using contact angle and X-ray photoelectron spectroscopic (XPS) measurements. XPS results showed that amines and alkanes were attached in 1-4 nm thickness covering approximately 20% and 45%, respectively, of the surface. Patterns of amines were visualized using fluorescent staining, and patterns of proteins were detected immunochemically. Patterned coverslips were used to investigate adhesion and neurite outgrowth of mouse neuroblastoma (N1E-115) cells. Cells were examined on the following patterns: alkane-glass, protein-glass, amine-alkane, and amine-protein. Cell attachment and neurite outgrowth on patterned coverslips displayed the following preferences: laminin, fibronectin, or collagen IV > amine or glass > alkane or bovine serum albumin. This patterning method should be useful for studies of cell-surface interactions, cell migration, nerve regeneration, and the formation of neural networks in vitro.
We have proposed the Intelligent Operation Support System (IOSS) for sewage plants, which can be applied to bulking prediction and control for the activated sludge process. The IOSS can provide guidance and control me...
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We have proposed the Intelligent Operation Support System (IOSS) for sewage plants, which can be applied to bulking prediction and control for the activated sludge process. The IOSS can provide guidance and control messages to operators on actions to Lake based on various kinds of integrated information including on-line process data, image signals on microorganisms, heuristics on plant control and data analyzed manually. To get on-line microorganism image information, a high resolution submerged microscope was developed and applied in a full scale plant. By combining image data with heuristics, the loss allows prediction of the symptoms of abnormal phenomena like bulking occurrence, and then provides ways to control the abnormalities thus decreasing the operators' work loads. Furthermore, diagnosis methods for detecting sensor troubles are proposed. Simulation results indicate the IOSS is effective.
The following notes have been compiled for the guidance of authors who are preparingpapers for submission to Chinese Geographical *** of papersPapers may be sent for editorial consideration to the Editorial *** the ed...
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The following notes have been compiled for the guidance of authors who are preparingpapers for submission to Chinese Geographical *** of papersPapers may be sent for editorial consideration to the Editorial *** the editors has the responsibility for deciding whether a paper is to be accepted, re-jected or referred back to the author for amendment. He will be guided by the advice
To improve microwave hyperthevmia in cancer therapy, the thermal effect of fer-rimagnetic resonance (FMR) during microwave irradiation was studied. Resonant temperatureelevation (RTE) of single crystal grain and polyc...
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To improve microwave hyperthevmia in cancer therapy, the thermal effect of fer-rimagnetic resonance (FMR) during microwave irradiation was studied. Resonant temperatureelevation (RTE) of single crystal grain and polycrystal powder of resonant media was measuredalone and in imitative muscle and egg white and in mice. The results indicated that the RTE produced by FMR could be used to improve penetrationdeepness, heating selectivity and temperature distribution of microwave hyperthermia in cancertreatment. It was expected that the potential function of the FMR heating system would be ex-ploited greatly for cancer therapy, and then magnetically guided microwave hyperthermia thera-py, chemotherapy, radiotherapy and immunotherapy might he combined multiply within this sys-tem by means of the static magnetic field (SMF) and magnetic microcarrier. Limitation of reso-nant heating was also discussed in this paper.
The Naval Postgraduate School is currently conducting research in the area of autonomous underwater vehicles. 1 support of this research, the school has developed a testbed vehicle and graphic simulation. One of the m...
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The Naval Postgraduate School is currently conducting research in the area of autonomous underwater vehicles. 1 support of this research, the school has developed a testbed vehicle and graphic simulation. One of the major thrusts • the project is the development of a control system. This work explores the implementation and testing of a guidance scheme proposed by Kanayama called spatial acking. The method is evaluated with and without consideration for AUV dynamics. Spatial tracking is also com- ired with an earlier guidance scheme attributed to Kanayama known as cross track guidance. The NPS AUV testbed vehicle and simulator are also described within this work.
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