大学院工学研究院

武居 昌宏

タケイ マサヒロ  (Masahiro Takei)

基本情報

所属
千葉大学 大学院工学研究院総合工学講座 教授
学位
博士(工学)(1995年3月 早稲田大学)

ORCID ID
 https://orcid.org/0000-0003-3855-7202
J-GLOBAL ID
200901064060287550
researchmap会員ID
1000182863

外部リンク

論文

 358
  • Soichiro Ueno, Daisuke Kawashima, Katsuhiro Matsuura, Hiromichi Obara, Ryou Tanaka, Masahiro Takei
    Bioelectrochemistry 163 2025年6月  
    Heparin concentration c in a blood extracorporeal circulation has been real-timely predicted based on the relaxation strength Δεm at relaxation frequency fm extracted by relaxation time distribution (RTD). The simulated extracorporeal circulation was conducted to optimize the number of Δεm for the prediction of c using the porcine whole blood (WB) and low-leukocyte and −platelet blood (LLPB) under the condition of the gradual increment of c from 0 to 8 U/mL with constant flow rate and blood temperature. The experimental results show that among the three relaxation strengths Δε1, Δε2 and Δε3 (in ascending order of frequency), Δε2 at f2 = 5.2 ∼ 6.2 MHz and Δε3 at f3 = 42 ∼ 50 MHz were correlated to c. The Δε3 was decreasing with increasing c in both cases, which was influenced by the plasma macromolecular concentrations, while the Δε2 was increased with increasing c in WB case but was hardly changed in LLPB case because the Δε2 is influenced by the blood cell concentrations and the shape changes of blood cell membranes. Heparin concentration c is estimated by the linear regression formula cPRE=a1(Δε2-Δε2c=0)+a2(Δε3-Δε3c=0) (a1 = -0.991, a2 = -0.123) within the mean absolute percentage error (MAPE) of 0.291.
  • Arbariyanto Mahmud Wicaksono, Daisuke Kawashima, Ryoma Ogawa, Shinsuke Akita, Masahiro Takei
    Biomedical physics & engineering express 11(2) 2025年1月31日  
    Albumin andγ-globulin concentrations in subcutaneous adipose tissues (SAT) have been quantified by multivariate regression based on admittance relaxation time distribution (mrARTD) under the fluctuated background of sodium electrolyte concentration. ThemrARTD formulatesP=Ac+Ξ(P: peak matrix of distribution function magnitudeγˆand relaxation timesτˆ,c: concentration matrix of albumincAlb,γ-globulinGloc, and sodium electrolyteNac,A: coefficient matrix of a multivariate regression model, andΞ: error matrix). ThemrARTD is implemented by two processes which are: (1) the training process ofAthrough the maximum likelihood estimation ofPand (2) the quantification process ofcAlb,Gloc, andNacthrough the model prediction. In the training process, a positive correlation is present betweencAlb,Gloc, andNactoγˆ1atτˆ1= 0.1 as well asγˆ2atτˆ2= 1.40 μs as under a fixed concentration of proteins solution into a porcine SAT (cAlb= 0.800-2.400 g/dL,Gloc= 0.400-1.200 g dl-1andNac= 0.700-0.750 g dl-1). ThemrARTD method quantifiescAlb,Gloc, andNacin SAT with an absolute error of 33.79%, 44.60%, and 2.18%, respectively.
  • 上野 総一朗, 川嶋 大介, 松浦 功泰, 田中 綾, 武居 昌宏
    91(942) 24-00208 2025年  
  • Galih Setyawan, Kiagus Aufa Ibrahim, Ryoma Ogawa, Prima Asmara Sejati, Hiroshi Fujimoto, Hiroto Yamamoto, Masahiro Takei
    Biomedical physics & engineering express 10(6) 2024年9月19日  
    Breast cancer detection and differentiation of breast tissues are critical for accurate diagnosis and treatment planning. This study addresses the challenge of distinguishing between invasive ductal carcinoma (IDC), normal glandular breast tissues (nGBT), and adipose tissue using electrical impedance spectroscopy combined with Gaussian relaxation-time distribution (EIS-GRTD). The primary objective is to investigate the relaxation-time characteristics of these tissues and their potential to differentiate between normal and abnormal breast tissues. We applied a single-point EIS-GRTD measurement to ten mastectomy specimens across a frequency rangef= 4 Hz to 5 MHz. The method calculates the differential ratio of the relaxation-time distribution functionΔγbetween IDC and nGBT, which is denoted byΔγIDC-nGBT,andΔγbetween IDC and adipose tissues, which is denoted byΔγIDC-adipose.As a result, the differential ratio ofΔγbetween IDC and nGBTΔγIDC-nGBTis 0.36, and between IDC and adiposeΔγIDC-adiposeis 0.27, which included in theα-dispersion atτpeak1=0.033±0.001s.In all specimens, the relaxation-time distribution functionγof IDCγIDCis higher, and there is no intersection withγof nGBTγnGBTand adiposeγadipose.The difference inγsuggests potential variations in relaxation properties at the molecular or structural level within each breast tissue that contribute to the overall relaxation response. The average mean percentage errorδfor IDC, nGBT, and adipose tissues are 5.90%, 6.33%, and 8.07%, respectively, demonstrating the model's accuracy and reliability. This study provides novel insights into the use of relaxation-time characteristic for differentiating breast tissue types, offering potential advancements in diagnosis methods. Future research will focus on correlating EIS-GRTD finding with pathological results from the same test sites to further validate the method's efficacy.

MISC

 282

書籍等出版物

 41

講演・口頭発表等

 879
  • Yosephus Ardean Kurnianto Prayitno, Yoshiyuki Iso, Tong Zhao, Masahiro Takei
    International Conference on Nuclear Engineering, Proceedings, ICONE 2019年5月18日
    Copyright © 2018-2019 by JSME The demand for high separation efficiency needs an advanced device which can be installed in the separation machinery. To meet this demand, the development of a wireless electrical resistance detector (WERD) was introduced. This research presents particle sedimentation thickness detection method in centrifugal separation system using WERD. The main focus is to observe the particle sedimentation thickness in the specific positions inside an industrial-scale centrifuge. The wireless apparatus has an excellent performance in ultra-high rotation operating speed due to its light weight and flexibility. In this study, the solid phase was represented by acrylic particles of diameter D = 10μm. The acrylic particles were mixed with NaCl solutions and pumped into the centrifuge. As a result, the particle sedimentation thickness nearer to the liquid discharge port is low. Under Re1 = 383.71, the thickness at Z1 = 0.8D and at Z3 = 1.4 are lP1 = 1.15 mm and lP3 = 1.84 mm, respectively. A higher feeding flow rate gives a thicker particle sedimentation thickness. Under Re2 = 1151.15 at Z3 = 1.4D, the particle sedimentation thickness increases by 43%. These results are relative to the constant relative centrifugal force, RCF = 2130G therefore we conclude that the separation efficiency can be optimized by controlling the feeding rate and the rotational velocity of the centrifuge. These findings confirm that WERD is able to monitor the separation process in a centrifuge.
  • Wuqiang Yang, Zhen Ren, Masahiro Takei, Jiafeng Yao
    IST 2018 - IEEE International Conference on Imaging Systems and Techniques, Proceedings 2018年12月14日
    © 2018 IEEE. While electrical capacitance tomography (ECT) and electrical impedance tomography (EIT) have found many successful industrial applications, only recently, research into medical applications of ECT and EIT were carried out at University of Manchester and Chiba University, including (1) Visualization of tooth surface by ECT for tooth canal treatment, (2) Visualization by ECT and EIT for revision hip replacement surgery, (3) Microfluidics for cell sensing and manipulation, (4) Imaging clots in blood flows and (5) Non-intrusive diagnosis of lymph problems. This paper will review the above medical applications of electrical tomography, from necessity of the work or problems to be addressed, sensing principles, experiment arrangement to some initial results. In addition, other research related to medical application of electrical tomography will also be briefly reviewed, such as by Swisstom AG in Switzerland, Dartmouth College in USA and some universities in China.
  • Daisuke Kawashima, Xiayi Liu, Michiko Sugawara, Hiromichi Ohara, Masahiro Takei
    MHS 2017 - 28th 2017 International Symposium on Micro-NanoMechatronics and Human Science 2018年2月28日
    © 2017 IEEE. Electrical impedance spectroscopy (EIS) has been proven to be a useful technique for analyzing biological cell suspensions and tissues because of its capacity of noninvasive measurement. In this paper, the electrical characteristics of medical research council cell strain 5 (MRC-5) are detected by EIS in a multi-layered microchannel. In this research, the equivalent circuit of MRC-5 solution is created by the principle of cell electrical properties. In the experiments, MRC-5 and yeast cells are detected by EIS in multi-layered microchannel, the results reveal that EIS in the micro sensor distinguishes the different cells by their different electrical impedance.
  • Min-Ho Jeon, Kyung-Youn Kim, Masahiro Takei
    2016 IEEE INTERNATIONAL INSTRUMENTATION AND MEASUREMENT TECHNOLOGY CONFERENCE PROCEEDINGS 2016年 IEEE
    It is important to get reliable measurement data in Electrical impedance tomography (EIT) for getting satisfactory reconstruction result. Because EIT inverse problem is non-linear and ill-posed, incorrect data such as measured data through fault electrode can effect the estimation of resistivity distribution. So, EIT measurement system with methods for checking reliability has been developed. However, most existing methods require extra cost to evaluate reliability of EIT system. This paper presents modified Gauss-Newton (GN) method based on random sample consensus (RANSAC) algorithm for finding fault electrodes and getting good reconstructed image with faulty data for two-phase flow application. Also, suitable residual equation is proposed for determining the threshold to use RANSAC algorithm. Numerical simulations are performed to validate the performance of the proposed method. The results show that the proposed method has a good reconstruction performance compared to the conventional GN method.

主要な共同研究・競争的資金等の研究課題

 104

メディア報道

 1