•Consider coordinated traffic signal controls under both deterministic and stochastic demands.•A new mixed integer linear programming (MILP) for deterministic optimization is proposed.•The MILP has a ...network structure and its size is smaller than the existing formulations.•The problem is extended to treat the stochastic fluctuations in traffic demand.•An accurate and efficient approximation method of expected delays is developed.•Optimal control parameters for deterministic and stochastic controls are examined.
This study considers an optimal coordinated traffic signal control under both deterministic and stochastic demands. We first present a new mixed integer linear programming (MILP) for the deterministic signal optimization wherein traffic flow is modeled based on the variational theory and the constraints on a signal control pattern are linearly formulated. The resulting MILP has a clear network structure and requires fewer binary variables and constraints as compared with those in the existing formulations. We then extend the problem so as to treat the stochastic fluctuations in traffic demand. We here develop an accurate and efficient approximation method of expected delays and a solution method for the stochastic version of the signal optimization by exploiting the network structure of the problem. Using a set of proposed methods, we finally examine the optimal control parameters for deterministic and stochastic coordinated signal controls and discuss their characteristics.
► A methodology is proposed to combine fixed and probe sensor data to reconstruct vehicle trajectories on signalized arterials. ► Probe trajectories are used as reference to reconstruct the ...trajectories of other vehicles. ► Proposed method is applied to real world data and its robustness is confirmed by changing the input data characteristics. ► The basic methodology is extended so as to incorporate the vehicles coming in and out from midblock intersections.
A data fusion framework is examined to reproduce vehicle trajectories on urban arterials by combining probe and fixed sensor data, and signal timing parameters. The methodology is based on the kinematic wave theory and employs the variational theory for the solution method. However, the original methodology cannot deal with the vehicles coming in and out in the middle of the study section despite the frequent existence of such vehicles in the real world. Therefore, the methodology is extended so as to incorporate the vehicles coming in and out. The proposed method is then applied to real world data and its robustness is confirmed by changing the input data characteristics.
A thalidomide-binding aptamer was produced by systematic evolution of ligands by exponential enrichment from a library of non-natural DNA in which thymidine had been replaced with a modified ...deoxyuridine bearing a cationic functional group via a hydrophobic methylene linker at the C5 position. The additional functional group in the modified DNA aptamer could improve stability against nucleases and increase the binding affinity to thalidomide. The selected aptamer could recognize thalidomide enantioselectively, although a racemic thalidomide-attached gel was used for the selection. Surface plasmon resonance and fluorescence titration studies revealed that the selected modified DNA aptamer and a truncated version bound with an (R)-thalidomide derivative with high enantioselectivity, but not with the (S)-form. The modified group in the DNA aptamer is indispensable for the interaction with thalidomide, as the corresponding natural type DNA bearing the same base sequence showed no binding affinity with (R)- nor (S)-thalidomide. Computational sequence analysis suggested that the selected apatamer (108mer) could fold into a three-way junction structure; however, truncation of this aptamer (31mer) revealed that the thalidomide-binding site is a hairpin-bulge region that is a component of one of the arms of the three-way junction structure. The K d value of the truncated 31mer aptamer for binding with the (R)-thalidomide derivative was 1.0 μM estimated from fluorescence titration study. The aptamer that can recognize a single enantiomer of thalidomide will be useful as a biochemical tool for the analysis and study of the biological action of thalidomide enantiomers.
We have developed a 500-kV, 10-mA photocathode DC gun for energy recovery linac (ERL) light sources. A segmented ceramic insulator with guard rings is employed to improve robustness at high voltage ...operation, because this structure can prevent field emission electrons from directly striking the ceramic surface. We have recently succeeded in applying 500 kV on the ceramics for eight hours without any discharge. This high voltage testing was performed with a simple configuration without NEG pumps, cathode and anode electrodes to mainly study the field emission from a tube supporting the cathode electrode. The same high voltage testing with a full configuration necessary for beam generation was carried out up to 380 kV where some increase of radiation was observed. Up-to-date status of our gun development is presented in detail.
Embryonic stem (ES) cells have pluripotency and give rise to many cell types and tissues, including representatives of all three germ layers in the embryo. We have reported previously that mouse ES ...cells formed contracting gut‐like organs from embryoid bodies (EBs). These gut‐like structures contracted spontaneously, and had large lumens surrounded by three layers, i.e. epithelium, lamina propria and muscularis. Ganglia were scattered along the periphery, and interstitial cells of Cajal (ICC) were distributed among the smooth muscle cells. In the present study, to determine whether they can be a model of gut organogenesis, we investigated the formation process of the gut‐like structures in comparison with embryonic gut development. As a result, we found that the fundamental process of formation in vitro was similar to embryonic gut development in vivo. The result indicates that the gut‐like structure is a useful tool not only for developmental study to determine the factors that induce gut organogenesis, but also for studies of enteric neurone and ICC development.
Development of Spin-Polarized Pulsed TEM Kuwahara, M; Ichihashi, F; Kusunoki, S ...
Journal of physics. Conference series,
01/2012, Letnik:
371, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Recent nanointegration of magnetic storage and spintronic devices is expected to lead to the development of systems that can analyze magnetic and spin states with a nanometer-order spatial ...resolution. Development of a polarized transmission electron microscope (SPTEM) that employs a spin-polarized electron source (PES) has commenced at Nagoya University. A spin-polarized electron beam is extracted from a photocathode that has a negative electron affinity surface. The temporal profile of the electron beam can be modulated by varying the temporal profile of the driving laser. The SPTEM can obtain temporal and spatial information about spin. The design and construction of the PES were optimized for the SPTEM. A beam energy of less than 40 keV (a low energy for a TEM) was used because the spin interaction with condensed matter is very small compared with the Coulomb interaction. A polarized electron gun was realized in an extreme high vacuum by applying a high field gradient of 4 MV/m to the photocathode surface. A 40-keV polarized electron beam with sub-millisecond pulses was generated using a backside-excited photocathode. The illumination system of the TEM was designed with the aim of producing a spin-polarized electron beam. The system contains two components that rotate spin: one performs azimuthal rotation and the other performs in-plane rotation in the condenser magnet system. The SPTEM has the potential to dynamically generate magnetic-field images with high contrast and high temporal resolution.
Bromide ion removal from a real water matrix by hydrortalcite-like compounds (HTCs) was attempted in a column reactor to control the formation of brominated disinfection by-products in drinking water ...treatment process. The performance of HTCs was found to be comparable to a commercially available ion exchange resin for relatively low alkalinity water. Also, it was deduced that HTCs are better than ion exchange resins for high sulfate water because of their unique ion selectivity. In addition, the ion exchange reactions by HTCs were faster than a commercially available resin. Thus, HTCs are expected to provide similar performance to organic resins without the concern about secondary contamination (i.e., elution of organic compounds from resins).
This paper presents a new methodology for optimizing the signal timing controls of oversaturated networks based on the cell transmission model and a goal programming technique with multiple ...objectives. The proposed model accounts for intersection spillovers, equity in delays, and system throughputs. This new formulation is solved by genetic algorithms to obtain signal timing plans. A case study with a nine-intersection network and a comparison between the proposed model and the throughput-maximizing strategy are examined. It is found that the new method can efficiently minimize spillovers, balance delay equity, and provide reasonable system throughputs in their respective order for oversaturated networks. The result also indicates that the throughput-maximizing strategy does not always yield minimum spillovers for oversaturated networks and occasionally provides a larger difference in average link delay at a spillover intersection than the proposed model does.
Oneway carsharing service operators must assess the importance of each station relative to overall demand if resources are limited. We propose a variation of an innovation diffusion model designed to ...estimate new “hesitant” and “fast” adopters for different stations of a one-way carsharing system to understand system adoption dynamics better over time and to derive policy implications. We forecast the number of monthly new adopters and potential market of stations considering their synergistic effects. We further reflect the spatially diverse adoption dynamics during the initial years of a carsharing service. Stations are classified into four groups based on their location and demand pattern. The models are estimated using data from the Ha:mo RIDE carsharing system in Toyota, Japan. We observe two peaks in the new user curve that our model can explain. We propose that the initial peak is caused by information diffusion, whereas the later peak is due to market saturation. Policy relevant implications are that we observe a low degree of follower effect and that new stations in strategic locations are essential for continued demand growth. More specifically, we suggest that carsharing stations in residential areas experience demand stagnation fast, whereas continued demand growth can be expected and quantified for carsharing stations around transit hubs and public facilities. Therefore carsharing operators need to be aware that assessing the importance of a station for the overall system requires time as well as consideration of synergy effect with other service points.
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