A Study on Ship’s Autopilot System for a Small Boat

Toshihiko NAKATANI,Makoto ENDO,Keiji SASAYA,Takashi MIWA,Hiroshi MIKAMI,Taizo KANEDA,Emi KANAYAMA,Erika URA 제어로봇시스템학회 2011 제어로봇시스템학회 국제학술대회 논문집 Vol.2011 No.10

This paper describes dynamics analysis of a small training boat and the application of a gain map PID controller to the autopilot of the vessel. After upgrading the autopilot of the Sazanami, an actual small training boat, in order to identify the boat model, zigzag maneuver trials were performed at various speeds. It was found that the Nomoto gain and time constant changed considerably with the vessel’s speed. Based on this analysis, an improved autopilot system that utilizes a gain map PID controller to compensate for vessel maneuverability changes was designed. From the results of various control simulations, we determined that the proposed system offered significant performance improvements over the vessel’s conventional autopilot.

Changes in work accuracy in a noisy environment

Yanbin Wu,Makoto Uchida,Yuh Sasawaki,Maki Kado,Gamini Lokuketagoda,Takashi Miwa 한국마린엔지니어링학회 2017 한국마린엔지니어링학회지 Vol.41 No.5

A study of difficulty factors in piping diagram reading in an engine room simulator environment

Nozomi Takemura,Gamini Lokuketagoda,Masumi Nakamura,Makoto Uchida,Takashi Miwa 한국마린엔지니어링학회 2020 한국마린엔지니어링학회지 Vol.44 No.4

Demand for an engine room simulator has recently increased. Several manufacturers provide 3-dimensional animation or computer graphic imaging for application in virtual reality technology. Furthermore, educational tool hardware are improving on a daily basis. As educational institute researchers, we consider the planning of effective training exercises based on a simulated envi-ronment. In addition to hardware-related issues, software-related issues also exist in educational situations. One of the major difficul-ties associated with solving these problems is adjusting the task level according to the skill of the student, for which it must be known if the students are in fact finding any difficulty. We therefore conducted a questionnaire survey and factor analysis to detect the latent factors that affect the degree of difficulty, using data gathered via a questionnaire survey. Based on the findings of a questionnaire survey, we presented the difficulty factors encountered by students in understanding an engine room piping diagram.

Fatigue condition under the engine room environment and improving work accuracy

Yanbin Wu,Yuh Sasawaki,Maki Kado,Hossein Enshaei,Makoto Uchida,Takashi Miwa 한국마린엔지니어링학회 2018 한국마린엔지니어링학회지 Vol.42 No.2

Size-segregated Allergenic Particles Released from Airborne Cryptomeria japonica Pollen Grains during the Yellow Sand Events within the Pollen Scattering Seasons

Qingyue Wang,Xiumin Gong,Miho Suzuki,Senlin Lu,Kazuhiko Sekiguchi,Daisuke Nakajima,Makoto Miwa 한국대기환경학회 2013 Asian Journal of Atmospheric Environment (AJAE) Vol.7 No.4

Cryptomeria japonica pollen is the most common pollen,which are scattering during each spring season in Japan. Japanese cedar (Cryptomeria japonica) pollinosis is one of seasonal allergic rhinitis that mainly occurs in Japan. In addition, long range transportation of Yellow Sand from the East Asian continent was also found during the pollen scattering seasons in Japan. Therefore, the interaction or impact between pollen and Yellow Sand should be concerned. In this study, our objective was to investigate the airborne behaviour of Cryptomeria japonica pollen grains and its size-segregated allergenic (Cry j 1)particles as the airborne tracer of Cryptomeria japonica pollen during the Yellow Sand events. Airborne Cryptomeria japonica pollen grains and its size-segregated allergenic particles were collected at roadside of urban residential zones of Saitama city during the pollination periods from February to March in two year investigation of 2009 and 2010. The overlap of Yellow Sand events and dispersal peak of pollen grains was observed. According to the Meteorological data,we found that the peaks of airborne pollen grains appeared under higher wind speed and temperature than the previous day. It was thought that Yellow Sand events and airborne pollen counts were related to wind speed. From the investigation of the airborne behavior of the size-segregated allergen particles by determining Cry j 1 with Surface Plasmon Resonance (SPR), the higher concentrations of the allergenic Cry j 1 were detected in particle size equal to or less than 1.1 μm(PM1.1) than other particle sizes during Yellow Sand events, especially in the rainy day. We conclude that rainwater trapping Yellow Sand is one of the important factors that affect the release of allergenic pollen species of Cry j 1. Therefore, it is very important to clarify the relationships between Cryptomeria japonica pollen allergenic species and chemical contents of the Yellow Sand particles in further studies.

Diurnal and Nocturnal Behaviour of Airborne Cryptomeria japonica Pollen Grains and the Allergenic Species in Urban Atmosphere of Saitama, Japan

Wang, Qingyue,Nakamura, Shinichi,Lu, Senlin,Nakajima, Daisuke,Suzuki, Miho,Sekiguchi, Kazuhiko,Miwa, Makoto Korean Society for Atmospheric Environment 2013 Asian Journal of Atmospheric Environment (AJAE) Vol.7 No.2

Japanese cedar (Cryptomeria japonica) pollinosis is the most popular pollinosis in Japan. It has been reported that Cryptomeria japonica pollen allergenic species are suspended as fine particles in the urban atmosphere. These allergenic fine particles are responsible for inducing asthma by breaking into the lower respiratory tract. It has also been found that pollinosis symptoms on the sufferers appear mainly at night-time by the results from epidemiological studies. However, the exact reason for these phenomena is not yet clarified. In this study, the diurnal and nocturnal behaviours of Cryptomeria japonica pollen grains and their allergenic species in the urban area of Saitama city of Kanto Plain were investigated. Airborne pollen grains and allergenic Cry j 1 concentrations in total suspended particulate matter (TSP) were investigated at two sampling sites, a heavy traffic road (roadside site) and at the balcony of the $10^{th}$ floor of the Building of Research and Project of Saitama University (general urban site). The latter sampling site where located about 300 m away from the roadside site was used as a general urban site unaffected by automobile traffic. The airborne pollen counts were measured with a real-time pollen monitor. Cry j 1 particles were collected with two high volume air samplers, and these concentrations were measured by surface plasmon resonance method with a Biacore J system. The diurnal variation of the airborne pollen counts was similar to the trends of temperature and wind speed during the day-time; whereas its tendency with wind speed trend was not observed during the night-time. Airborne pollen counts were lower with northern wind than with southern wind because the pollen comes from the mountainous areas, and the mountains in the south are closer, about half the distance to the northern mountains. It is suggested that the peaks of airborne pollen counts during night-time in the sampling site occurred by transport of pollen grains released during day-time in the mountainous forest areas, located c.a. 100 km away from the sampling site. On the roadside site the allergenic Cry j 1 concentrations were higher than at the general urban site, nevertheless pollen grains counts were lower. These results suggested that worsening of pollinosis symptoms during night-time in urban area was caused by transport of pollen grains during day-time in the mountainous forest areas. Moreover, pollen allergenic species become different morphology from pollen grain at roadside site, and the subsequent pollen grains re-suspension by automobile traffic.

Diurnal and Nocturnal Behaviour of Airborne Cryptomeria japonica Pollen Grains and the Allergenic Species in Urban Atmosphere of Saitama, Japan

Qingyue Wang,Shinichi Nakamura,Senlin Lu,Daisuke Nakajima,Miho suzuki,Kazuhiko Sekiguchi,Makoto Miwa 한국대기환경학회 2013 Asian Journal of Atmospheric Environment (AJAE) Vol.7 No.2

Japanese cedar (Cryptomeria japonica) pollinosis is the most popular pollinosis in Japan. It has been reported that Cryptomeria japonica pollen allergenic species are suspended as fine particles in the urban atmosphere. These allergenic fine particles are responsible for inducing asthma by breaking into the lower respiratory tract. It has also been found that pollinosis symptoms on the sufferers appear mainly at night-time by the results from epidemiological studies. However, the exact reason for these phenomena is not yet clarified. In this study, the diurnal and nocturnal behaviours of Cryptomeria japonica pollen grains and their allergenic species in the urban area of Saitama city of Kanto Plain were investigated. Airborne pollen grains and allergenic Cry j 1 concentrations in total suspended particulate matter (TSP)were investigated at two sampling sites, a heavy traffic road (roadside site) and at the balcony of the 10th floor of the Building of Research and Project of Saitama University (general urban site). The latter sampling site where located about 300 m away from the roadside site was used as a general urban site unaffected by automobile traffic. The airborne pollen counts were measured with a real-time pollen monitor. Cry j 1 particles were collected with two high volume air samplers, and these concentrations were measured by surface plasmon resonance method with a Biacore J system. The diurnal variation of the airborne pollen counts was similar to the trends of temperature and wind speed during the day-time;whereas its tendency with wind speed trend was not observed during the night-time. Airborne pollen counts were lower with northern wind than with southern wind because the pollen comes from the mountainous areas, and the mountains in the south are closer, about half the distance to the northern mountains. It is suggested that the peaks of airborne pollen counts during night-time in the sampling site occurred by transport of pollen grains released during day-time in the mountainous forest areas, located c.a. 100 km away from the sampling site. On the roadside site the allergenic Cry j 1 concentrations were higher than at the general urban site, nevertheless pollen grains counts were lower. These results suggested that worsening of pollinosis symptoms during nighttime in urban area was caused by transport of pollen grains during day-time in the mountainous forest areas. Moreover, pollen allergenic species become different morphology from pollen grain at roadside site, and the subsequent pollen grains re-suspension by automobile traffic.

Characterization of the Physical Form of Allergenic Cry j 1 in the Urban Atmosphere and Determination of Cry j 1 Denaturation by Air Pollutants

Qingyue Wang,Jun Morita,Xiumin Gong,Shinichi Nakamura,Miho Suzuki,Senlin Lu,Kazuhiko Sekiguchi,Takuya Nakajima,Daisuke Nakajima,Makoto Miwa 한국대기환경학회 2012 Asian Journal of Atmospheric Environment (AJAE) Vol.6 No.1

In this study, we characterized the physical form of allergenic Cry j 1 in the urban atmosphere. Through an immunofluorescence antibody method, we showed that allergenic Cry j 1 exists as fine particles (‹1.1μm). To determine Cry j 1 concentrations and its particle size distribution, we used the ELISA method to confirm that most Cry j 1 exists as fine particles in the urban atmosphere and is found at high concentrations on fine day next to rainy day. Furthermore,we evaluated Cry j 1 denaturation by using the Biacore J system based on the surface plasmon resonence (SPR) principle and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). We showed that the dissociation constant (KD) of Cry j 1 that has been exposed to urban polluted air is lower (1.76×10-14 M) than that of Cry j 1 (1.32×10-9-3.37×10-9 M) of original pollen grains that has not been exposed to air pollutants. Cry j 1 turns into low molecular weight proteins by reacting with various acidic solutions. In sum, we showed that allergenic Cry j 1exists as fine particles that can deposit in the lower respiratory tract. This finding clarifies the relationship between Japanese cedar pollinosis and air pollutants.