Study of High Speed SRM Using Vector Control for Electric Vehicle

K. Aiso,M. Takaha shi,K. Akatsu 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

In order to realize downsizing motor in an electric vehicle (EV), the high speed motor is effective. Switched Reluctance Motor (SRM) is suitable for the high speed drive because the rotor has simple and robust structure. However, as a disadvantage, the vibration and the acoustic noise are large. Moreover, the complicated unipolar current excitation results in the difficulty of the torque controller design. To overcome these problems, the vector control has been proposed for SRM. However, the vector control has not been applied to the SRM in the high speed region. In this paper, the drive conditions such as switching frequency, bus voltage to apply the vector control to the SRM in the high speed region are clarified. It is shown by the experiment that the proposed SRM can be driven by the vector control in the high speed region and can realize the high output power and low vibration.

Variations in Growth Characteristics and Stress-wave Velocities of Zelkova serrata Trees from Eight Half-sib Families Planted in Three Different Initial Spacings

Prasetyo, Agung,Endo, Ryota,Takashima, Yuya,Aiso, Haruna,Hidayati, Fanny,Tanabe, Jun,Ishiguri, Futoshi,Iizuka, Kazuya,Yokota, Shinso Institute of Forest Science 2015 Journal of Forest Science Vol.31 No.3

Zelkova serrata is an important hardwood species for the timber industry in Japan. Tree breeding programs for this species have mainly focused on growth characteristics such as stem diameter (D), tree height (TH), stem form, and branching. In order to fulfill timber industry needs, wood quality improvement should be included in the tree breeding program of this species. In the present study, growth characteristics, such as D and TH, and the stress-wave velocity (SWV), which is highly correlated with Young's modulus of wood, were measured for 20-year-old Z. serrata from eight half-sib families planted in a progeny test site with three different initial spacings. Significant differences in all the measured characteristics were found among the eight half-sib families. The variance components of the half-sib families for D, TH, and SWV were 27.2%, 47.3%, and 33.5%, respectively. These results indicate that all the measured characteristics of this species could be improved by tree breeding programs. In addition, only low correlation coefficients were obtained between the growth characteristics and SWV, indicating that extensive selection on SWV in tree breeding programs may not always lead to a reduction in yield volume.

Variations in Growth Characteristics and Stress-wave Velocities of Zelkova serrata Trees from Eight Half-sib Families Planted in Three Different Initial Spacings

Agung Prasetyo,Ryota Endo,Yuya Takashima,Haruna Aiso,Fanny Hidayati,Jun Tanabe,Futoshi Ishiguri,Kazuya Iizuka,Shinso Yokota 강원대학교 산림과학연구소 2015 Journal of Forest Science Vol.31 No.3

Zelkova serrata is an important hardwood species for the timber industry in Japan. Tree breeding programs for this species have mainly focused on growth characteristics such as stem diameter (D), tree height (TH), stem form, and branching. In order to fulfill timber industry needs, wood quality improvement should be included in the tree breeding program of this species. In the present study, growth characteristics, such as D and TH, and the stress- wave velocity (SWV), which is highly correlated with Young’s modulus of wood, were measured for 20-year-old Z. serrata from eight half-sib families planted in a progeny test site with three different initial spacings. Significant differences in all the measured characteristics were found among the eight half-sib families. The variance components of the half-sib families for D, TH, and SWV were 27.2%, 47.3%, and 33.5%, respectively. These results indicate that all the measured characteristics of this species could be improved by tree breeding programs. In addition, only low correlation coefficients were obtained between the growth characteristics and SWV, indicating that extensive selection on SWV in tree breeding programs may not always lead to a reduction in yield volume.

Preliminary evaluation of anatomical characteristics of four common Mongolian softwoods

Sarkhad Murzabyek,Ishiguri Futoshi,Nezu Ikumi,Aiso Haruna,Ngadianto Agus,Tumenjargal Bayasaa,Baasan Bayartsetseg,Chultem Ganbaatar,Ohshima Jyunichi,Yokota Shinso 한국산림과학회 2022 Forest Science And Technology Vol.18 No.3

To effectively and sustainably utilize wood resources from boreal forests in Mongolia, ana- tomical characteristics, tracheid morphology, cell proportion, annual ring width, and late- wood percentage were preliminary determined in Pinus sylvestris, Pinus sibirica, Picea obovata,andLarix sibirica trees naturally growing in Mongolia. Based on the observation, the anatomical characteristics of four common Mongolian softwoods were the same as those previously observed in the same species or the same genus species. Based on the parame- ters of the Gompertz functions for annual ring width, silvicultural management, such as thin- ning timing and harvesting age, should be considered depending on the species when the plantation is established. The results of the model selection for relationships between late- wood percentage and basic density indicated that the increase ratio of basic density corre- sponded to an increase of latewood percentage is almost the same irrespective of species, although there are species-specific values of basic density corresponding to specific late- wood percentages. The results obtained in the present study contribute effective and sus- tainable utilization of wood resources from Mongolian forestry.

Three-dimensional analysis of dermal backflow in cancer-related lymphedema using photoacoustic lymphangiography

Anna Oh,Hiroki Kajita,Nobuaki Imanishi,Hisashi Sakuma,Yoshifumi Takatsume,Keisuke Okabe,Sadakazu Aiso,Kazuo Kishi 대한성형외과학회 2022 Archives of Plastic Surgery Vol.49 No.1

Background Dermal backflow (DBF), which refers to lymphatic reflux due to lymphatic valve insufficiency, is a diagnostic finding in lymphedema. However, the three-dimensional structure of DBF remains unknown. Photoacoustic lymphangiography (PAL) is a new technique that enables the visualization of the distribution of light-absorbing molecules, such as hemoglobin or indocyanine green (ICG), and can provide three-dimensional images of superficial lymphatic vessels and the venous system. This study reports the use of PAL to visualize DBF structures in the extremities of patients with lymphedema after cancer surgery. Methods Patients with a clinical or lymphographic diagnosis of lymphedema who previously underwent surgery for cancer at one of two participating hospitals were included in this study. PAL was performed using the PAI-05 system. ICG was administered subcutaneously in the affected hand or foot, and ICG fluorescence lymphography was performed using a near-infrared camera system prior to PAL. Results Between April 2018 and January 2019, 21 patients were enrolled and examined using PAL. The DBF was composed of dense, interconnecting, three-dimensional lymphatic vessels. It was classified into three patterns according to the composition of the lymphatic vessels: a linear structure of lymphatic collectors (pattern 1), a network of lymphatic capillaries and lymphatic collectors in an underlying layer (pattern 2), and lymphatic capillaries and precollectors with no lymphatic collectors (pattern 3). Conclusions PAL showed the structure of DBF more precisely than ICG fluorescence lymphography. The use of PAL to visualize DBF assists in understanding the pathophysiology and assessing the severity of cancer-related lymphedema.

Photoacoustic lymphangiography before and after lymphaticovenular anastomosis

Oh, Anna,Kajita, Hiroki,Matoba, Eri,Okabe, Keisuke,Sakuma, Hisashi,Imanishi, Nobuaki,Takatsume, Yoshifumi,Kono, Hikaru,Asao, Yasufumi,Yagi, Takayuki,Aiso, Sadakazu,Kishi, Kazuo Korean Society of Plastic and Reconstructive Surge 2021 Archives of Plastic Surgery Vol.48 No.3

Background Lymphaticovenular anastomosis (LVA) is a minimally invasive surgical procedure used to treat lymphedema. Volumetric measurements and quality-of-life assessments are often performed to assess the effectiveness of LVA, but there is no method that provides information regarding postoperative morphological changes in lymphatic vessels and veins after LVA. Photoacoustic lymphangiography (PAL) is an optical imaging technique that visualizes the distribution of light-absorbing molecules, such as hemoglobin or indocyanine green (ICG), and provides three-dimensional images of superficial lymphatic vessels and the venous system simultaneously. In this study, we performed PAL in lymphedema patients before and after LVA and compared the images to evaluate the effect of LVA. Methods PAL was performed using the PAI-05 system in three patients (one man, two women) with lymphedema, including one primary case and two secondary cases, before LVA. ICG fluorescence lymphography was performed in all cases before PAL. Follow-up PAL was performed between 5 days and 5 months after LVA. Results PAL enabled the simultaneous visualization of clear lymphatic vessels that could not be accurately seen with ICG fluorescence lymphography and veins. We were also able to observe and analyze morphological changes such as the width and the number of lymphatic vessels and veins during the follow-up PAL after LVA. Conclusions By comparing preoperative and postoperative PAL images, it was possible to analyze the morphological changes in lymphatic vessels and veins that occurred after LVA. Our study suggests that PAL would be useful when assessing the effect of LVA surgery.