研究者詳細 - 谷川　寛樹

論文 - 谷川　寛樹

分割表示 252 件中 21 - 40 件目／全件表示 >>

Sustainable assessment and resource recycling opportunities identification for China's pig industry: Integrating environmental, economic and social perspectives 査読有り

Bai, YY; Zhai, YJ; Zhang, TZ; Ren, K; Jia, YK; Zhou, XY; Cheng, ZY; Tanikawa, H; Hong, JL

SUSTAINABLE PRODUCTION AND CONSUMPTION 39 巻頁： 425 - 437 2023年7月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Sustainable Production and Consumption

Livestock plays a vital role in the livelihoods and nutritional security of people worldwide and leads to significant environmental challenges. Manure management is a major hurdle for sustainable livestock development and serves as a critical source of natural fertilizer and green energy. Given that pork accounts for the highest meat production and consumption share, this study systematically evaluates China's pig production and main manure resource utilization scenarios from life-cycle environmental, economic, and social perspectives. Results show that China's pig production poses considerable potential environmental risks, primarily in the categories of fossil depletion, freshwater ecotoxicity, particulates formation, global warming, and water depletion. Feed production coupled with traditional manure treatment scenario contributes to 94.4 %–98.4 % of the key environmental impact categories and socioeconomic impact, with 32.0 % to 38.3 % of the economic costs also stemming from feed costs. In the energy utilization scenario, the potential benefits of fossil depletion and global warming categories resulting from the replacement of synthetic fertilizers with manure-based organic fertilizers in the traditional pig manure treatment scenario could be expanded by 89.6 % and 39.2 %, respectively. China's pig production contributed 0.72 % of the national carbon emissions in 2020. Fully utilizing energy potential and organic fertilizer from pig manure would achieve 0.63 % of national carbon reduction potential, as well as an economic benefit of $1.45 × 1012 and a social benefit of $8.89 × 109. Precision feeding technology, rebuilding the spatial connection between pig farms and arable land, and internalizing external costs were recommended to ensure the sustainable development of China's pig industry.

DOI： 10.1016/j.spc.2023.05.018

Web of Science

Scopus

Uncovering urban transportation infrastructure expansion and sustainability challenge in Bangkok: Insights from a material stock perspective 査読有り

Khumvongsa, K; Guo, J; Theepharaksapan, S; Shirakawa, H; Tanikawa, H

JOURNAL OF INDUSTRIAL ECOLOGY 27 巻 ( 2 ) 頁： 476 - 490 2023年4月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Industrial Ecology

Development of transportation infrastructure that extends roads and railways in Bangkok has overlooked the negative environmental impact of construction material accumulation. To analyze the extent of this impact, we originally established road and railway's material intensity coefficients and investigated spatially explicit roadway and railway material stock (MS) for the years of 2004, 2009, 2014, 2019, and 2037, based upon the master plans’ target year. We further analyzed how MS evolution relates to the city's socio-economic indicators and CO2 emission. Significant growth is found in transportation MS during 2004–2019, and roadways particularly increased from 122 to 164 million metric tons (Mt). The master plans would require 43 and 6.55 Mt construction materials for roadway and railway extension, respectively, by 2037. More material-intensive roads (cross-provincial highways and major local roads) built to the suburbs of the cities and underground/elevated structures of the mass rapid transit system in dense urban areas will require three times the annual cement and steel consumption of that in the 2004–2019 period. Furthermore, a 2–3 fold increase in the number of registered vehicles and associated CO2 emissions during the study period have brought questions to the transportation infrastructure MS efficiency. The findings of this study will enable informed decision-making regarding the concern of resource consumption and for considering environmentally friendly approaches in urban transportation planning for Bangkok and other developing cities.

DOI： 10.1111/jiec.13342

Web of Science

Scopus

日本における建設資材ストック・フローの時空間分析査読有り

太田裕也, 山下奈穂, 蛭田有希, 白川博章, 谷川寛樹

環境情報科学 52 巻 ( 1 ) 頁： 120 - 120 2023年3月

滞留年数の延長による資源循環及び気候変動緩和への影響評価査読有り

藤川奈々, 山下奈穂, 蛭田有希, 白川博章, 谷川寛樹

環境情報科学 52 巻 ( 1 ) 頁： 119 - 119 2023年3月

Does Deep Learning Enhance the Estimation for Spatially Explicit Built Environment Stocks through Nighttime Light Data Set? Evidence from Japanese Metropolitans 査読有り

Liu, ZW; Saito, R; Guo, J; Hirai, C; Haga, C; Matsui, T; Shirakawa, H; Tanikawa, H

ENVIRONMENTAL SCIENCE & TECHNOLOGY 57 巻 ( 9 ) 頁： 3971 - 3979 2023年3月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Environmental Science and Technology

Built environment stocks have attracted much attention in recent decades because of their role in material and energy flows and environmental impacts. Spatially refined estimation of built environment stocks benefits city management, for example, in urban mining and resource circularity strategy making. Nighttime light (NTL) data sets are widely used and are regarded as high-resolution products in large-scale building stock research. However, some of their limitations, especially blooming/saturation effects, have hampered performance in estimating building stocks. In this study, we experimentally proposed and trained a convolution neural network (CNN)-based building stock estimation (CBuiSE) model and applied it to major Japanese metropolitan areas to estimate building stocks using NTL data. The results show that the CBuiSE model is capable of estimating building stocks at a relatively high resolution (approximately 830 m) and reflecting spatial distribution patterns, although the accuracy needs to be further improved to enhance the model performance. In addition, the CBuiSE model can effectively mitigate the overestimation of building stocks arising from the blooming effect of NTL. This study highlights the potential of NTL to provide a new research direction and serve as a cornerstone for future anthropogenic stock studies in the fields of sustainability and industrial ecology.

DOI： 10.1021/acs.est.2c08468

Web of Science

Scopus

PubMed

Spatial-temporal dynamics of the built environment toward sustainability: A material stock and flow analysis in Chinese new and old urban areas 査読有り

Yang, D; Dang, MY; Guo, J; Sun, LW; Zhang, RR; Han, F; Shi, F; Liu, Q; Tanikawa, H

JOURNAL OF INDUSTRIAL ECOLOGY 27 巻 ( 1 ) 頁： 84 - 95 2023年2月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Industrial Ecology

The urban built environment has accumulated massive amounts of resources, which is the main “hot spot” of construction materials and energy consumption in cities. To effectively monitor and manage resources use and waste disposal toward sustainability, this study intended to explore different metabolic paths of the urban built environment, as well as strategies for new and old urban areas separately with the help of material stock and flow analysis. Based on snapshots of 2003, 2010, and 2017 and combined with big data, a four-dimensional geographic information system buildings database of Lixia District in Jinan, China, was compiled for bottom-up stock modeling. Finally, the environmental impact assessment of the buildings’ demolition and disposal stage was carried out. The results showed that the building material stock was 142.31 Mt in 2017, with an increase of 69% from 2003. The reinforced concrete buildings increased rapidly from 2003 to 2017, especially in new urban areas, which has boosted demand for steel and cement by more than 150% during these 15 years. The material stock of the old urban area tends to be saturated, whereas the new urban area has experienced a rapid expansion with the material inflow four times as large as the material outflow. Potential recycling of waste concrete can reduce the generation of building demolition waste by 50%, save 0.15 km2 of land occupation, increase raw material substitution by nearly 10 times, and reduce CO2 emissions by 2.5 times.

DOI： 10.1111/jiec.13335

Web of Science

Scopus

Estimation of the Lifespan of Imported Passenger Vehicles in Mongolia 査読有り Open Access

Mendjargal, T; Yamasue, E; Tanikawa, H

SUSTAINABILITY 14 巻 ( 21 ) 2022年11月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Sustainability (Switzerland)

In the last few decades, there has been an increase in second-hand imported vehicles in developing countries, including Mongolia. However, the extension of vehicle lifespans abroad promotes circular economy activities. In this study, we investigated the lifespan of second-hand imported passenger vehicles and their implication for the future sustainability of the transportation sector in Mongolia. The methodology used in this study comprised three stages. First, we conducted surveys to investigate the trends in second-hand vehicles in Mongolia. Next, the results from the survey on passenger vehicles were classified into three major categories based on their mode of operation, namely fuel, liquefied gas petroleum (gas), and the hybrid engine vehicle (HV) (of which the Toyota Prius is the most used vehicle in Mongolia). Finally, we estimated the average lifespan of vehicles using the Weibull distribution to measure before and after the import. The results show that the total average lifespans of all vehicles range between 17.3 and 20.2 years, respectively. The results highlight the different shape parameters of each vehicle category (fuel, gas, and HV), providing a better understanding of each vehicle’s lifespan and providing insights on the future management of second-hand imported vehicles, lifecycles, and recycling potentials for the successful development of sustainable transport policies in Mongolia.

DOI： 10.3390/su142114582

What matters most to the material intensity coefficient of buildings? Random forest-based evidence from China 査読有り

Zhang, RR; Guo, J; Yang, D; Shirakawa, H; Shi, F; Tanikawa, H

JOURNAL OF INDUSTRIAL ECOLOGY 26 巻 ( 5 ) 頁： 1809 - 1823 2022年10月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Industrial Ecology

Material intensity coefficient (MIC) is vital for material stock accounting in the field of industrial ecology. However, the categorization of MIC varies across regions especially for buildings that diverge greatly along the history and space aspect, and acquisition of MIC data and building information have always been a challenge in related studies. In this study, the state-of-art ensemble model “Random Forest” was developed on Chinese buildings to identify the impact of four building attributes (building structure, construction year, use type, and region) on MIC, and these features’ importance was further assessed by considering variable correlations. The features’ importance and their individual effects on MIC were intuitively revealed by depicting the partial dependence plots. Finally, a set of hierarchical MIC values was estimated by integrating the order of four variables’ importance and a quick MIC calculator was provided. Results showed that building structure is the most influential attribute for MIC, followed by the construction year, use type, and region, successively. The RF-based MIC values allow researchers to apply it to material stock and flow analysis by choosing a specific building feature(s) in the MIC calculator, which is (are) available in building physical inventory data. This study provides a method that could help researchers locate key influencing variables and give insights into the comparability of MIC research across regions and play an important role in developing urban mining and circular economy strategies.

DOI： 10.1111/jiec.13332

Web of Science

Scopus

researchmap

Application of GIS and Machine Learning to Predict Flood Areas in Nigeria 査読有り Open Access

Ighile, EH; Shirakawa, H; Tanikawa, H

SUSTAINABILITY 14 巻 ( 9 ) 2022年5月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Sustainability (Switzerland)

Floods are one of the most devastating forces in nature. Several approaches for identifying flood-prone locations have been developed to reduce the overall harmful impacts on humans and the environment. However, due to the increased frequency of flooding and related disasters, coupled with the continuous changes in natural and social-economic conditions, it has become vital to predict areas with the highest probability of flooding to ensure effective measures to mitigate impending disasters. This study predicted the flood susceptible areas in Nigeria based on historical flood records from 1985~2020 and various conditioning factors. To evaluate the link between flood incidence and the fifteen (15) explanatory variables, which include climatic, topographic, land use and proximity information, the artificial neural network (ANN) and logistic regression (LR) models were trained and tested to develop a flood susceptibility map. The receiver operating characteristic curve (ROC) and area under the curve (AUC) were used to evaluate both model accuracies. The results show that both techniques can model and predict flood-prone areas. However, the ANN model produced a higher performance and prediction rate than the LR model, 76.4% and 62.5%, respectively. In addition, both models highlighted that those areas with the highest susceptibility to flood are the low-lying regions in the southern extremities and around water areas. From the study, we can establish that machine learning techniques can effectively map and predict flood-prone areas and serve as a tool for developing flood mitigation policies and plans.

DOI： 10.3390/su14095039

Open Access

Web of Science

Scopus

From efficiency to equity: Changing patterns of China's regional transportation systems from an in-use steel stocks perspective 査読有り国際共著

Xu, ST; Wang, HX; Tian, X; Wang, T; Tanikawa, H

JOURNAL OF INDUSTRIAL ECOLOGY 26 巻 ( 2 ) 頁： 548 - 561 2022年4月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Industrial Ecology

Transportation serves as a bridge for social production, distribution, exchange, and consumption and, thus, plays an important role in boosting the economy. In recent years, the rapid development of China's transportation system has driven a continuous accumulation of steel. In this study, we estimated the in-use steel stocks of 32 types of infrastructure and vehicles in three subsystems (railway, road, and subway) in 31 provinces of China from 1990 to 2019 based on a bottom-up approach. The results show that China's in-use steel stock in the transportation system has increased to 575 Mt in 2019 (34.4% for infrastructure, 65.6% for vehicle). Spatially, this increasing trend shows six diversified patterns among 31 provinces; steel stocks tend to decrease from the east to central and western inland areas. The Gini coefficient curve of the provinces’ stocks shows an inverted “U” shape over time, indicating a shrinking regional gap in recent years; this reflects a transition from efficiency to equity. We also measured the steel stock productivity (GDP per stock) in different regions and observed its diverse evolution types. The stock productivities in all regions climbed up initially, but have dropped in recent years, and the most obvious decrease is observed in western China. For eastern regions, vehicles have been the main growth point in recent years, while western regions are vigorously developing infrastructure. Our results help to illustrate the development status and spatial distribution of China's transportation system and could facilitate improved efficiency and the management of future challenges in China's transformation and development.

DOI： 10.1111/jiec.13203

Web of Science

Scopus

第24 回（2021 年度）学術大会公開シンポジウム「循環経済（サーキュラーエコノミー）とSDGs」報告査読有り

松本亨, 中村崇, 工藤里恵, 林志浩, 松尾康志, 藤井実, 谷川寛樹

環境共生 38 巻 ( 1 ) 頁： 119 - 124 2022年3月

GIS を用いた同一性判定に基づく建築物のLCA 環境負荷の評価査読有り

太田裕也, 吉田英立, 白川博章, 谷川寛樹

環境情報科学 51 巻 ( 1 ) 頁： 117 - 117 2022年3月

名古屋市中心部における建設資材ストックと構造種割合の変遷査読有り

玉崎美結, 白川博章, 谷川寛樹

環境情報科学 51 巻 ( 1 ) 頁： 83 - 83 2022年3月

都市構造物ストック推計手法の再検討査読有り

松代竜毅, 山下奈穂, 白川博章, 谷川寛樹

環境情報科学 51 巻 ( 1 ) 頁： 82 - 82 2022年3月

衛星画像を用いた畳み込みニューラルネットワークによる建物延床面積推計に関する研究査読有り

齋藤隆成, LIU Zhiwei, 平井千津子, 芳賀智宏, 松井孝典, 白川博章, 谷川寛樹

環境情報科学 51 巻 ( 1 ) 頁： 84 - 84 2022年3月

機械学習モデルを用いた画像認識による建設資材ストック推計

長尾征洋, 竹内詢喜, 玉崎美結, 森田大登, 北栄輔, 白川博章, 谷川寛樹

土木学会論文集Ｇ（環境） 78 巻 ( 6 ) 頁： II_19 - II_25 2022年

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：公益社団法人土木学会

<p>　都市部における建設資材ストックを把握することは資源のリサイクルや適正処理のために重要である．正確なストック推定には建築物構造を推定する必要があるが，既往研究では近年増加しているカーテンウォールを備えた鉄骨造は分類されてこなかった．本研究では機械学習モデルを用い建物壁面画像からガラスと壁を判定し，各ピクセル数から壁面ガラス率を算出した．このガラス率67％を閾値として判別に用いるとカーテンウォールを備えた鉄骨造を適切に分類できることが分かった．名古屋駅周辺の262棟を対象に建物構造を分類しストック推計を行った結果，従来の分類方法と比較してコンクリートは18%減少，鋼材は325%増加することが示された．</p>

DOI： 10.2208/jscejer.78.6_ii_19

CiNii Research

非金属鉱物系資源の物量投入産出表の整備及び循環指標群への適用査読有り

山下奈穂, 橋本征二, 白川博章, 谷川寛樹

環境共生 38 巻 ( 2 ) 頁： 176 - 187 2021年11月

The urbanisation-environment conflict: Insights from material stock and productivity of transport infrastructure in Hanoi, Vietnam 査読有り国際共著 Open Access

Miatto, A; Dawson, D; Nguyen, PD; Kanaoka, KS; Tanikawa, H

JOURNAL OF ENVIRONMENTAL MANAGEMENT 294 巻頁： 113007 2021年9月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Journal of Environmental Management

Developing regions experience rapid population growth and urbanisation, which require large quantities of materials for civil infrastructure. The production of construction materials, especially for urban transport systems, however, contributes to local and global environmental change. Political agendas may overlook the environmental implications of urban expansion, as economic growth tends to be prioritised. While elevating the standard of living is imperative, decision-making without careful environmental assessments can undermine the overall welfare of society. In this study, we evaluate the material demand and in-use stock productivity for the large-scale development plan for transport infrastructure in the city of Hanoi, Vietnam, from 2010 to 2030, combining geospatial and socioeconomic data with statistics on roads and railways. The results show that the total material stock could rise threefold from 66 Tg in 2010 to 269 Tg in 2030, which roughly translates to an addition of 30 Empire State Buildings per year by mass. The materials we account are required for construction exceed the availability of local sand and will need to be gathered farther away. Furthermore, the material stock productivity of the transport infrastructure appears to have been declining overall since 2010, and this trend may continue to 2030. These findings demonstrate the importance of informing urban planning with a comprehensive assessment of construction materials demand, supply capacity, and environmental impacts. Policy priorities for improving the in-use stock productivity are also recommended towards achieving a more efficient utilisation of natural resources.

DOI： 10.1016/j.jenvman.2021.113007

Web of Science

Scopus

PubMed

木造住宅と森林の木材需給を考慮した炭素ストックのシナリオ分析査読有り

山下奈穂, 加用千裕, 谷川寛樹

環境科学会誌 34 巻 ( 4 ) 頁： 184 - 195 2021年7月

記述言語：日本語掲載種別：研究論文（学術雑誌）出版者・発行元：社団法人環境科学会

<p>本研究では，木造住宅と森林の将来炭素ストックに関するシナリオ分析を行う。従来の炭素ストック定量化に関する研究では，住宅もしくは森林の一側面のみに着目したものが多く，日本の住宅と森林の炭素ストックを総合的に評価するものは少ない。特に，住宅は都市における炭素ストックと考えられ，長寿命化などの住宅政策が木材需給及び炭素ストックにもたらす影響を考慮する必要がある。そこで本研究では，木造住宅における木材需要が森林の木材供給に影響を与えるモデルを作成し，将来の木造住宅と森林の合計炭素ストック量に関するシナリオ分析を行う。将来の木材需要を変化させる要因として木造住宅の総延床面積と耐用年数を挙げ，供給のために伐採・再植林される森林の齢級構成を踏まえて全体の炭素ストックをシナリオ間で比較する。推計の結果，現状維持シナリオでは木造住宅と森林の合計で2050年に10.5億t-C，2100年に10.1億t-Cの炭素ストックが算出された。木材の需要増と長寿命化の促進によって木造住宅と森林の合計炭素ストックは最も大きくなり，現状維持のシナリオと比較すると2100年の炭素ストックが1.3億t-C増加することが明らかになった。また，2100年までの本推計期間において，木造住宅の長寿命化は炭素ストックを増加させるが，長寿命化による炭素ストックの増加は耐用年数が長くなるほどゆるやかになることが明らかになった。本研究の対象外である木材利用による間接的なエネルギー消費削減効果及び炭素排出削減効果の評価を今後の課題とした上で，本推計結果からは長寿命化がある程度達成された後には，木材の利用拡大を重点的に行うほうが炭素ストックの増加により効果的であると示唆された。</p>

DOI： 10.11353/sesj.34.184

CiNii Research

High-Resolution Maps of Material Stocks in Buildings and Infrastructures in Austria and Germany 査読有り国際共著 Open Access

Haberl, H; Wiedenhofer, D; Schug, F; Frantz, D; Virág, D; Plutzar, C; Gruhler, K; Lederer, J; Schiller, G; Fishman, T; Lanau, M; Gattringer, A; Kemper, T; Liu, G; Tanikawa, H; van der Linden, S; Hostert, P

ENVIRONMENTAL SCIENCE & TECHNOLOGY 55 巻 ( 5 ) 頁： 3368 - 3379 2021年3月

記述言語：英語掲載種別：研究論文（学術雑誌）出版者・発行元：Environmental Science and Technology

The dynamics of societal material stocks such as buildings and infrastructures and their spatial patterns drive surging resource use and emissions. Two main types of data are currently used to map stocks, night-Time lights (NTL) from Earth-observing (EO) satellites and cadastral information. We present an alternative approach for broad-scale material stock mapping based on freely available highresolution EO imagery and OpenStreetMap data. Maps of built-up surface area, building height, and building types were derived from optical Sentinel-2 and radar Sentinel-1 satellite data to map patterns of material stocks for Austria and Germany. Using material intensity factors, we calculated the mass of different types of buildings and infrastructures, distinguishing eight types of materials, at 10 m spatial resolution. The total mass of buildings and infrastructures in 2018 amounted to 5 Gt in Austria and 38 Gt in Germany (AT: 540 t/cap, DE: 450 t/cap). Cross-checks with independent data sources at various scales suggested that the method may yield more complete results than other data sources but could not rule out possible overestimations. The method yields thematic differentiations not possible with NTL, avoids the use of costly cadastral data, and is suitable for mapping larger areas and tracing trends over time.

DOI： 10.1021/acs.est.0c05642

<谷川 寛樹>

論文 - 谷川 寛樹

<谷川　寛樹>

論文 - 谷川　寛樹