Dedicated parallel Processor SMASH for Sparse LU Decomposition

Nobuyuki Tanaka,Hideki Asai 대한전자공학회 1990 JTC-CSCC : Joint Technical Conference on Circuits Vol.- No.-

Emissions of Volatile Organic Compounds from a Hen Shed in Japan

Nobuyuki Tanaka,Megumi Ohtsu,Akane Miyazaki 한국대기환경학회 2020 Asian Journal of Atmospheric Environment (AJAE) Vol.14 No.3

To clarify the emissions of volatile organic compounds (VOCs) from hen rearing in Japan, we collected air samples from inside a hen shed for the four seasons in 2019 and analyzed 34 VOCs in the air samples by gas chromatography-mass spectrometry and high performance liquid chromatography. The temperature and humidity inside and outside of the shed were monitored simultaneously during each sampling campaign. The average concentrations of VOCs in the shed ranged from 150 to 427 µg m-3 , the concentrations being higher in summer and lower in winter. Acetone, dimethyl sulfide, 2-butanone, 2-pentanone, and acetic acid were dominant throughout all the seasons and these five compounds accounted for 70-89% of the total VOCs. The reactivity of each VOC with hydroxyl radical was also calculated and dimethyl sulfide was found to be the most reactive VOC, accounting for 84-94% of the total hydroxyl radical reactivity. The emission rate (ER) for the total VOCs(µg h-1 kg-1 ) was 602 in winter, 7,900 in spring, 46,500 in summer and 37,600 in autumn, respectively. Acetone, dimethyl sulfide, 2-butanone, 3-pentanone and acetic acid had higher ERs throughout all the seasons, and these five components accounted for 70-90% of the ERs for the total VOCs. The ERs of the VOCs increased exponentially in accord with temperature increases inside the shed, indicating that the ERs of the VOCs depended on the ambient temperature. The annual VOC emission from one hen and from the hen shed was calculated to be 405 g y-1 and 121 kg y-1 , respectively.

Emissions of Volatile Organic Compounds from a Dairy Cattle Shed in Japan

Nobuyuki Tanaka,Kaede Moriyama,Megumi Ohtsu,Akane Miyazaki 한국대기환경학회 2019 Asian Journal of Atmospheric Environment (AJAE) Vol.13 No.3

To clarify the nature and characteristics of volatile organic compounds (VOCs) emitted from dairy cattle within a cattle shed located in Chiba, Japan, air samples were collected and analyzed for the four seasons in 2017-2018. Thirty-four VOCs were determined by gas chromatography-mass spectrometry and high performance liquid chromatography. In addition, air temperature and relative humidity inside and outside of the shed were monitored during each sampling campaign to estimate the ventilation rate of the shed. The average concentrations of total VOCs (μg m-3) in the shed in each season were 50.5 (spring), 128.4 (summer), 168.8 (autumn), and 199.5 (winter). Ketones were always the most dominant components followed by alcohols and volatile fatty acids (VFAs). The sum of ketones, alcohols, and VFAs accounted for more than 80% of the total VOCs in all seasons. Acetone, 3-pentanone, 1-butanol, and acetic acid were the major components regardless of the season, accounting for more than 60% of the total VOCs. The average emission rates of total VOCs from the shed (μg h-1 kg-1) were calculated to be 623 (spring), 1520 (summer), 585 (autumn) and 469 (winter). The emission rates of almost all the VOCs except alcohols increased exponentially with increase of air temperature in the shed. The ranges of the emission rates for each class of chemical (μg h-1 kg-1) were 39-170 (VFAs), 247-913 (ketones), 65-134 (alcohols), 40-122 (phenols), 10-122 (aldehydes), 4.17- 22.3 (sulfur compounds), and 0.0067-0.74 (indoles). Furthermore, the annual emissions of VOCs for a single dairy cattle and for the cattle shed were estimated to be 5.5 kg and 44 kg, respectively.

Relationship between human behavior and indoor air quality of private room in a care facility for the elderly in Japan

Nobuyuki Tanaka,Tatsuji Munaka,Joao Filipe Papel,Shun‑ichi Hattori,Toshiya Iwamatsu,Teruhisa Miura,Fujio Tsutsumi 한국대기환경학회 2023 Asian Journal of Atmospheric Environment (AJAE) Vol.17 No.1

In Japan, the number of elderly people in need of nursing care is increasing while the population of young people is decreasing, and the potential for labor shortages in the field of elder care is of great concern. This study aimed to estimate the behavior of the elderly by using sensors to monitor indoor air quality (IAQ), without placing undue burden on the elderly or their caregivers. Odor and carbon dioxide ( CO2) concentrations were monitored in a private room of a nursing home in the Kanto Region of Japan, the behaviors of the resident and staff members were recorded, and the relationship between the two was analyzed. Both odor and CO2 concentrations were higher when the resident was present than when absent, indicating that the resident was one of the main sources of indoor odor and CO2. In addition, after the resident entered the room, the CO2 concentration increased and remained stable, whereas the odor concentration tended to vary after the resident entered the room, first increasing and later decreasing. This suggested that the increase or decrease in odor could be used to monitor the behavior of the resident and staff members. The relationship between the slopes of odor and CO2 in typical behavioral events suggest that if only odor increases and CO2 does not change, the likelihood of the event in which feces were observed during diaper changes is high. In addition, based on the behavior near the sensor, the rate of CO2 and odor emissions differed between the elderly resident and the younger staff members, suggesting that the ratio of odor slope to CO2 slope may be greater in the elderly than in younger people. Furthermore, the repeated number of increases and decreases in odor and CO2 suggested that multiple events could be distinguished. These results suggest that IAQ can be utilized to estimate the behavior of residents and staff in nursing care facilities for the elderly.

Real-time Monitoring of Bioaerosol in a Residential Property in Central Tokyo

Nobuyuki Tanaka 한국대기환경학회 2021 Asian Journal of Atmospheric Environment (AJAE) Vol.15 No.3

Real-time onsite monitoring of indoor airborne microbes in a residential property in central Tokyo was carried out in 2020 and 2021, following the onset of the COVID-19 pandemic. A microbial sensor utilizing fluorescence emitted by microorganisms was used to measure bioaerosol concentrations in the living room and children’s bedroom as well as on the balcony. Indoor PM2.5 was also monitored simultaneously at certain time points using a PM2.5 sensor. The behavior of the residents was also recorded during some monitoring periods. The average number concentration of microbes as fungi in the living room was 15,100, 58,800, and 10,600 counts m-3 in spring, summer, and winter, respectively, increasing in summer when the outside temperature was high. Microbial number concentrations were closely related to human behavior, increasing rapidly during periods of physical activity, but decreasing again within 20-30 min of the activity ending. There was no clear correlation between indoor microbial number concentrations and PM2.5 concentrations, suggesting that indoor microorganisms are concentrated in coarse particles, such as dust, which are quickly removed via gravitational settling. The concentration of indoor airborne microorganisms decreased significantly after ventilation, and although an occasional increase was observed immediately after ventilation, concentrations decreased again rapidly within 10-20 min. These results suggest that even a short period of ventilation can significantly reduce the indoor bioaerosol.

Influence of Human Behavior on Indoor Air Quality in a Care Facility for the Elderly in Japan

Nobuyuki Tanaka,Tatsuji Munaka 한국대기환경학회 2021 Asian Journal of Atmospheric Environment (AJAE) Vol.15 No.4

Volatile organic compounds (VOCs), CO2, temperature, and humidity in a private room in a care facility for the elderly were measured and the behavior of a resident and staff were recorded in order to clarify the effects of the resident’s behavior, especially defecation, on indoor air quality. Average indoor concentrations of total VOCs (in μg m-3) in summer, autumn, and winter were 40.9, 16.7, and 18.8, respectively. Average indoor concentrations of CO2 in summer, autumn, and winter were 813, 761, and 1144 ppm, respectively, revealing a tendency for the concentrations of CO2 to be higher in winter, in contrast to the VOC concentration. The concentrations of VOCs and CO2 were 1.1 to 1.5 times higher when the resident was present in the room than when the resident was absent. This result suggests that one of the main sources of VOC and CO2 emissions in indoor air was the resident. Acetic acid, 1-butanol, propanoic acid, hexanoic acid, and phenol, which are contained in human sweat, exhaled air, and excrement, were the predominant VOCs in the air of the room regardless of the season, and these five components accounted for more than 90% of the total VOCs. The concentrations of these components were higher when the resident was present in the room, suggesting that the resident was the main source of these components. Based on the changes in the VOC and CO2 concentrations over time and the records of the resident and the staff, it was noted that VOC concentrations decreased, in some cases, before and after diaper changes. Our research suggests that certain aspects of the behavior of residents can be inferred by monitoring changes in indoor air quality.

Associations between Vitamin D Receptor (VDR) Gene Polymorphisms and Colorectal Cancer Risk and Effect Modifications of Dietary Calcium and Vitamin D in a Japanese Population

Takeshige, Nobuyuki,Yin, Guang,Ohnaka, Keizo,Kono, Suminori,Ueki, Takashi,Tanaka, Masao,Maehara, Yoshihiko,Okamura, Takeshi,Ikejiri, Koji,Maekawa, Takafumi,Yasunami, Yohichi,Takenaka, Kenji,Ichimiya, Asian Pacific Journal of Cancer Prevention 2015 Asian Pacific journal of cancer prevention Vol.16 No.5

Much interest has been drawn to possible associations between vitamin D receptor (VDR) gene polymorphisms and colorectal cancer risk in conjunction with potentially protective effects of calcium and vitamin D. In a study of 685 cases of colorectal cancer and 778 community controls in Japan, we examined the associations of the FokI, BsmI, ApaI, and TaqI polymorphisms with colorectal cancer risk and effect modification by dietary calcium and vitamin D. Genotypes were determined by the PCR-RFLP method. The ApaI polymorphism seemed to be associated with a decreased risk of colorectal cancer, particularly of rectal cancer. The adjusted odds ratio of colorectal cancer for the ApaI AA and Aa genotypes combined versus the aa genotype was 0.83 (95% confidence interval [CI] 0.67-1.02), and the corresponding value for rectal cancer was 0.75 (95%CI 0.56-0.99). A decreased risk of colorectal cancer for the ApaI AA and Aa genotypes combined was more evident in individuals with high calcium intake (interaction p=0.055). The FokI polymorphism seemed to be associated with a decreased risk of colon cancer among those with high vitamin D intake (interaction p=0.09). The BsmI and TaqI polymorphisms were unrelated to colorectal cancer risk, and the null associations were not modified by calcium or vitamin D intake. In conclusion, the ApaI polymorphism may be associated with a decreased risk of colorectal cancer in Japanese, dependent on dietary calcium intake.

HIDE : Hierarchical Decomposition System for Preprocessing of Circuit Simulation

Masakatsu Nishigaki,Nobuyuki Tanaka,Hideki Asai 대한전자공학회 1990 JTC-CSCC : Joint Technical Conference on Circuits Vol.- No.-

Emissions of Volatile Organic Compounds from Dairy Cattle Manure in a Cattle Shed in Japan

Arika Aizawa,Akane Miyazaki,Nobuyuki Tanaka KOSAE·JSAE·CSES-CSAE 2022 Asian Journal of Atmospheric Environment (AJAE) Vol.16 No.3

The livestock industry is a major source of atmospheric volatile organic compounds (VOCs), but details on these emissions are not well documented in Japan. In particular, it remains unclear how the rearing method affects the emissions of VOCs from livestock, which originate primarily from feces and urine. Here we aimed to estimate the amounts of VOCs emitted from the feces and urine of tethered Holstein dairy cattle in a cattle shed in Japan. Dimethyl sulfide and acetone accounted for about 60% of the total VOCs emitted from feces, followed by formaldehyde and acetaldehyde. Also, dimethyl sulfide and acetone were the dominant VOCs emitted from urine, accounting for 90% of the total VOCs. The VOCs from manure were considered to be emitted between the excretion and removal of the manure during the cleaning of the shed. As a result of analyzing images from three cameras installed in the shed, the average time between excretion and cleaning during the daytime (8:00 am-5:00 pm) was 80 min for feces and urine, whereas at night (5:00 pm-7:00 am), the average time between excretion and cleaning was 480 min. Based on the above findings, the emissions of VOCs in the interval between excretion and cleaning of the shed were estimated. As a result, the emissions of VOCs from feces and urine per head of cattle in the shed were estimated to be 1.75 and 1.52 g day<SUP>-1</SUP>, respectively. Furthermore, contribution of VOCs emitted from manure to odor activity value (OAV) and hydroxyl radical reactivity (OHR) were also estimated. Volatile fatty acids and sulfur compounds emitted from feces estimated to have high contribution to OAV, whereas aldehydes contributed mainly for OHR from manure.

Emissions of Volatile Organic Compounds from a Swine Shed

Nao Osaka,Akane Miyazaki,Nobuyuki Tanaka 한국대기환경학회 2018 Asian Journal of Atmospheric Environment (AJAE) Vol.12 No.2

The concentrations and chemical compositions of volatile organic compounds (VOCs), including volatile fatty acids, phenols, indoles, aldehydes, and ketones, which are the main organic compounds generated by swine, were investigated in July and October 2016 and January 2017. In addition, the emission rates and annual emissions of these components from the swine shed were estimated. The concentrations of VOCs in the swine shed averaged 511.3 μg m-3 in summer, 315.5 μg m-3 in fall and 218.6 μg m-3 in winter. Acetone, acetic acid, propionic acid, and butyric acid were the predominant components of the VOCs, accounting for 80-88% of the total VOCs. The hourly variations of VOC concentrations in the swine shed in fall and winter suggest that the VOC concentrations were related to the ventilation rate of the swine shed, the activity of the swine, and the temperature in the swine shed. Accordingly, the emission rates of VOCs from the swine shed were 1-2×103 μg (h kg-swine)-1.