Study on the urban heat island mitigation effect achieved by converting to grass-covered parking

The urban heat island mitigation effect of conversion from asphalt-covered parking areas to grass-covered ones is estimated by observation and calculation. The mean surface temperature in a parking lot is calculated from a thermal image captured by an infrared camera. The sensible heat flux in each parking space is calculated based on the surface heat budget. The reduction in the sensible heat flux is estimated to be approximately 100-150 W m⁻² during the day and approximately 50 W m⁻² during the night, in comparison with an asphalt surface. The air temperature reduction by the spread of grass-covered parking areas is calculated to be about 0.1 °C. Furthermore, consideration is given to the appearance of the parking lot, the growth of grass, the effects of the weight of a car and the heat radiated from its engine, the costs of construction and maintenance, etc.     

Automatic Train Operation Using Autonomic Prediction of Train Runs

In this paper, we present an automatic train control method adaptable to disturbed train traffic conditions. The proposed method presumes transmission of detected time of a home track clearance to trains approaching the station by employing equipment of Digital ATC (Automatic Train Control). Using the information, each train controls its acceleration by a method that consists of two approaches. First, by setting a designated restricted speed, the train controls its running time to arrive at the next station in accordance with predicted delay. Second, the train predicts the time at which it will reach the current braking profile generated by Digital ATC, along with the time when the braking profile transits ahead. By comparing them, the train correctly chooses the coasting drive mode in advance to avoid deceleration due to the current braking profile. We evaluated the effectiveness of the proposed method regarding driving conditions, energy consumption, and reduction of delays by simulation. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 175(3): 65–73, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.10020/eej.21080     

Power system control method using customers' energy storage systems and the verification of proposed method

Advanced energy storage systems have been widely applied to industries and are being installed at large buildings and factories to realize efficient energy usage. This paper presents a control method involving load frequency control and distribution network control (loss reduction control) using a part of customers' owned battery capacity. When 10% of total battery capacity of 100 MW in a network of 30‐GW generator capacities is used for load frequency control, a total of 1500‐MW generation units for load frequency control, at maximum, can be stopped without deterioration of power quality. In addition, when batteries are used for loss reduction in a distribution network, 2% of the loss on a summer day can be reduced. To realize both effects to their fullest, a novel integrated control algorithm is proposed and its economic effect is evaluated by numerical simulations. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(4): 11–20, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20704     

Damage repair in CMSX-4 alloy without fatigue life reduction penalty

The microstructural changes in a single-crystal Ni-base superalloy, CMSX-4, that might occur during the processes of repair and recoating of hot section components for advanced gas turbines were studied. It is shown that the cellular γ/γ′ microstructure is formed when the material is subjected to local plastic straining, followed by the reheat treatments during the course of damage recovery. The formation of cellular microstructure in the material led to the remarkably reduced fatigue strength. In order to reduce or prevent the preceding undesirable effect resulting from cellular microstructure, a new method based on applying overlay coating technique was developed. The method is based on an idea that the alloying elements that are depleted in base alloys could be supplemented via the overlay coating. An X alloy, which contains grain boundary strengthening elements, was selected and coated on the CMSX-4 with the cellular microstructure by low-pressure plasma spraying. The fatigue tests on the coated CMSX-4 specimens demonstrated the effectiveness of the method. The observations of the crack initiation site, the fatigue fracture mode, the crack density in the cellular transformed area, and the crack propagation morphologies near the prior interface strongly supported the validity of this approach. The method is expected to build a road to a so-called damage cure (or recovery) coating.     

ESR study on radical polymerization of styrene

Summary Propagation rate constant (k_p) for styrene was evaluated at different chain lengths of the polymer radical based on the steady-state concentration of the polymer radical determined by means of ESR spectroscopy at 70°C. Over a range of degree of polymerization of the polymer radical from 40 to 410, the value of k_p, 480±10 L/mol·s, remained constant. A considerable increase in viscosity of the polymerization mixture did not affect this value.     

40-Gb/s packet-selective photonic add/drop multiplexer based on optical-code label header processing

A packet-by-packet-selective photonic add/drop multiplexer, of the finest data granularity, is experimentally demonstrated at 40 Gb/s. An optical-code label, attached to the packet, enables determination, in the optical domain, of whether to drop, cut through, or add packets.     

Monitoring of cerebrospinal fluid pressure during embolization of AVM

We experienced that therapeutic embolization of a large cerebral arteriovenous malformation (AVM) led to venous outflow obstruction resulting in intracranial hypertension in a patient who had undergone external decompression. To evaluate hemodynamic changes after embolization, we monitored the cerebrospinal fluid pressure in the next four patients who underwent endovascular treatment. The embolization of a medium AVM resulted in a slight increase in the cerebrospinal fluid pressure. In two medium AVMs, embolization produced slight decreases in the cerebrospinal fluid pressure. In a small AVM, we did not observe any changes in the cerebrospinal fluid pressure during the endovascular treatment. We discuss the mechanism of changes in the intracranial pressure after embolization and conclude that monitoring of the cerebrospinal fluid pressure immediately yields useful information for hemodynamic changes during endovascular treatment.     

Removal of Cr(VI) from aqueous solution by London plane leaves

The effect of initial metal concentration, contact time and solution temperature on the removal of Cr(VI) from solution by waste London plane leaves, generated by the pruning of street trees, was investigated in batch mode conditions. The removal of Cr(VI) was highly concentration‐dependent and mainly governed by physico‐chemical adsorption under the weak acidic conditions studied. The equilibrium data fit well in the Langmuir isotherm model. The Langmuir constants were calculated at different temperatures and both the adsorption capacity and adsorption intensity increased with rising temperature. The endothermic nature of the Cr(VI) adsorption was confirmed by the thermodynamic parameters. The study has shown that the waste leaves can be used as an effective adsorbent for removal of Cr(VI) from wastewater. Copyright © 2003 Society of Chemical Industry     

WDM field trials of 43-Gb/s/channel transport system for optical transport network

This paper describes recent technical challenges and the progress toward the realization of the optical transport network (OTN) based on 43 Gb/s channel. We describe the new digital frame format "OTU3: Optical Channel Transport Unit 3," which is standardized in ITU-T for OTN, for the enhancement of the network management capability in the OTN based on 43-Gb/s channels. We first proposed 43-Gb/s/ch dense wavelength-division multiplexing (DWDM) dispersion-managed transmission system using carrier-suppressed return-to-zero (CS-RZ) format that has several attractive features; it advances the evolution of OTN into 100 GHz-spaced long-haul DWDM transport networks. The first wavelength-division multiplexing (WDM) field trials confirmed the superiority of CS-RZ format in the DWDM transmission performance for the first time. The first 1 Tb/s (25 /spl times/ 43 Gb/s) WDM field trial confirmed the excellent network management capability of OTU3 in future data-centric OTN using the newly developed 43-Gb/s OTN line-terminal prototype.     

Ultrahigh-speed driverless MQW intensity modulator, and 20 Gbit/s, 100 km transmission experiments

An InGaArInAlAs MQW modulator with the low voltage of 1.5 V for 10 dB extinction ratio and 16 GHz bandwidth has been developed. This ultrahigh-speed modulator enables the modulator driver to be eliminated from the transmitter. 100 km transmission experiments have been carried out using either a 1 V peak to peak output monolithic-IC-driven modulator at 15 Gbit/s or a 2 V peak to peak output multiplexer-driven modulator at 20 Gbit/s. This is the first report on multigigabit operation of MQW modulators to the authors' knowledge.<>