Yasuyuki Ishida 교수

Identifying the main factors influencing the land surface temperature (LST) of each local climate zone (LCZ) built type is of great significance for controlling LST. This study investigated the main factors influencing the LST of each LCZ built type in two Asian megacities: Tokyo and Shanghai. Each area in both megacities was classified according to the LCZ scheme. The diurnal LST, pervious surface fraction (PSF), surface albedo (SA), average building height (⟨BH⟩), and gross building coverage r

Abstract The Local Climate Zone (LCZ) scheme is an urban classification system which classifies urban areas into discrete local climates by morphological and land cover characteristics, proposed based on urban heat island researches in 1970s to 2000s. However, while the original scheme defines high‐rise buildings as areas higher than 25 m on average, buildings over 100 m have become more common in Asia since the 2000s. With the heterogeneity of urban areas, directly applying the original LCZ sch

High-rise buildings cause accelerated winds around them. However, the interference effects of high-rise buildings on the surrounding low-rise buildings in urban blocks have not been evaluated. This study investigated the wind pressure coefficients on the roofs and walls of low-rise buildings surrounding a high-rise building through wind tunnel experiments. Seventy-two wind directions were considered from 0° to 355° in 5° increments, and the influence of the wind direction on the wind pressure co

Capturing useful data in a complex and dense urban space is an inherently challenging task. There is so much data people can capture in a city, yet they may fail to capture important information, some of which they don’t even know that it exists. In this paper, we discuss an implicit approach to urban sensing and introduce an implicit sensing system that combines wearable sensors and mobile phone networks to support early-stage exploration of urban issues. An important technical issue that arose

The use of sea breeze with a huge cool potential has been regarded as one of the effective countermeasures against urban heat island phenomenon, and many studies have reported the effect of sea breeze on reducing air temperature. On the other hand, atmospheric observations have been conducted to understand the characteristics of wind in the urban boundary layer. Especially, in recent years, with the development of remote sensing technology, many studies to measure the mean or turbulent character

Transmission characteristics of 1.3-μm-band single-mode optical fibers were studied experimentally and theoretically. OH-ion content dependence of optical loss in the 1.3-μm region was investigated on single-mode fibers fabricated by the VAD method. The optical loss was evaluated for OH-ion content by calculating correlation factors between the optical loss and 1.39-μm OH-peak absorption loss. It was clarified that the optical loss calculated by correlation factors agreed approximately with the

Most previous studies clarify the interference effect between only two or three buildings, and very few assess the effect of a high-rise building within an urban block on its surrounding buildings. Accordingly, in this study, wind tunnel experiments were conducted on low-rise urban blocks having a high-rise building, and the wind pressure acting on the low-rise buildings was measured. For low-rise buildings located downwind of a high-rise building, an extremely low negative peak pressure was obs

In this paper we describe a prototype system of identifying environment condition utilizing signals emitted by people. Many people move around in many places such as urban and mountain areas. If each person emits information about identifying the state of the place where he/she and all the information is collected to one site, we can know the state of an area. Based on the idea, we have extended WINFO, a previously developed system, to accommodate reading people's walking conditions obtained by

In recent years, high dense cities such as Tokyo and Hong Kong are facing serious problems regarding thermal comfort and air quality of outdoor space caused by the poor ventilation in cities. Urban ventilation has been regarded as an effective countermeasure against such problems in many studies. The majority of previous attempts for improving urban ventilation have focused on the methods to lead the horizontal wind inside the urban area by reducing building coverage ratio, that is, to secure “h