The Hardware CPG Model for Humanoid Robot HOAP2

Shiho Akazawa,Yoshifumi Sekine 대한전자공학회 2007 ITC-CSCC :International Technical Conference on Ci Vol.2007 No.7

In recent years, the development of humanoid robots is advancing rapidly. Development of robots, which are learning, is being widely improved, for example robots, which can work in harmony with humans. However, for the humanoid robot’s information processing system to simulate a human being’s brain function, research in neural networking must be greatly advanced. We are researching to control robots using pulse-type hardware neuron model modeling the pulse form of an actual human brain. In this paper, we propose the hardware CPG (Central Pattern Generator) model using software for humanoid robot HOAP2. We clarify the stability in the step movement by using the hardware CPG model.

The application of machine learning for predicting recurrence in patients with early-stage endometrial cancer: a pilot study

Munetoshi Akazawa,Kazunori Hashimoto,Katsuhiko Noda,Kaname Yoshida 대한산부인과학회 2021 Obstetrics & Gynecology Science Vol.64 No.3

ObjectiveMost women with early stage endometrial cancer have a favorable prognosis. However, there is a subset of patientswho develop recurrence. In addition to the pathological stage, clinical and therapeutic factors affect the probabilityof recurrence. Machine learning is a subtype of artificial intelligence that is considered effective for predictive tasks. We tried to predict recurrence in early stage endometrial cancer using machine learning methods based on clinicaldata. MethodsWe enrolled 75 patients with early stage endometrial cancer (International Federation of Gynecology and Obstetricsstage I or II) who had received surgical treatment at our institute. A total of 5 machine learning classifiers were used,including support vector machine (SVM), random forest (RF), decision tree (DT), logistic regression (LR), and boostedtree, to predict the recurrence based on 16 parameters (age, body mass index, gravity/parity, hypertension/diabetic,stage, histological type, grade, surgical content and adjuvant chemotherapy). We analyzed the classification accuracyand the area under the curve (AUC). ResultsThe highest accuracy was 0.82 for SVM, followed by 0.77 for RF, 0.74 for LR, 0.66 for DT, and 0.66 for boosted trees. The highest AUC was 0.53 for LR, followed by 0.52 for boosted trees, 0.48 for DT, and 0.47 for RF. Therefore, the bestpredictive model for this analysis was LR. ConclusionThe performance of the machine learning classifiers was not optimal owing to the small size of the dataset. The useof a machine learning model made it possible to predict recurrence in early stage endometrial cancer.

Bone Mineral Density and Physical Performance of Female Patients 27 Years or Longer after Surgery for Adolescent Idiopathic Scoliosis

Tsutomu Akazawa,Toshiaki Kotani,Tsuyoshi Sakuma,Takehide Katogi,Shohei Minami,Hisateru Niki,Yoshiaki Torii,Shigeta Morioka,Sumihisa Orita,Kazuhide Inage,Kazuki Fujimoto,Yasuhiro Shiga,Kazuhisa Takahas 대한척추외과학회 2017 Asian Spine Journal Vol.11 No.5

Study Design: Retrospective cohort study. Purpose: To assess bone mineral density (BMD) and bone metabolism ≥27 years after surgery in female patients who underwent spinal fusion for adolescent idiopathic scoliosis (AIS) during adolescence and to determine their associations with physical performance. Overview of Literature: There are no studies investigating postsurgical BMD in middle-aged AIS patients. Methods: This study included 23 patients who provided informed consent among 229 female patients with AIS who underwent spinal fusion from 1968 until 1988. Average age at the time of observation was 48.8 years. BMD was measured at the left femoral neck, and the levels of two bone metabolism markers– procollagen type 1 N-terminal propeptide (P1NP) and tartrate-resistant acid phosphatase 5b (TRACP-5b)–were measured from blood samples. Physical performance was measured using grip strength, sit-ups, sit-andreach, side step, and standing long jump. Results: Mean BMD was 0.784 g/cm2. According to the World Health Organization diagnostic criteria, one subject (4.3%) had osteoporosis, whereas nine subjects (39.1%) had osteopenia. In patients with osteoporosis or osteopenia, P1NP and TRACP-5b levels were high, and BMD loss was because of high metabolic turnover. All calculated standard scores for physical performance were lower in the study cohort than in healthy individuals. There was a positive correlation between BMD and the standard score for grip strength, whereas there were weak positive correlations between BMD and the standard scores for side step and standing long jump. Conclusions: In female AIS patients who underwent spinal fusion in adolescence, 4.3% and 39.1% had osteoporosis and osteopenia, respectively, ≥27 years after surgery. Exercise performance of these patients was poor compared with the national standards. In these patients, increased physical activity should be encouraged to prevent BMD loss in middle age.

특별기고 : 동경재판과 전쟁책임

아카자와시로 ( Akazawa Shiro ) 한국민족연구원 2006 민족연구 Vol.0 No.28

TVコマ-シャルを使用した日本語授業

赤澤幸 한국일어일문학회 2003 日語日文學硏究 Vol.46 No.1

この論文の目的は, 最近の技術發展とともにます多樣化している視聽覺メディアの中からTVコマ-シャルを取り上げ, 外國語としての日本語授業における具體的な使用方法について考察することである. 第2章では, いわゆる「視聽覺メィア敎材」について, 最近さまな意味で用いられていることから, その定義について確認する. そして, 現視点での敎育環境に照らし合わせて, TVコマ-シャルを日本語敎育で使用する際のもっとも現實的で有效な視聽覺メディアについて考えてみる. 第3章では, 多樣な外國語敎育理論を踏まえながら, 日本語授業におけるTVコマ-シャル使用の利点につて論じる. 第4章では, TVコマ-シャルを構成する要素を分析する. 特に, 視覺と聽覺による知覺に注目し, 映像で提示される素材に畵像と字幕, 音聲で提示される素材に音, 音樂, 歌, 發話があることを示す. さらに, 素材ごとに學習者に傳達される情報が言語的情報か非言語的情報かを分析することによって, 敎師が授業に使用するTVコマ-シャルをどのように選擇すればいいか, その基準となるものを示唆する. 第5章では, TVコマ-シャルを使用した敎室活動の具體的なアイデアを示す. もっとも效果的に使用するために, TVコマ-シャルのタイブを字幕仕立て, 歌仕立て, 會話仕立てなど7つのタイブに分類し, それぞれの特徵に適した使用のためのアイデアを考察する. 第6章では, TVコマ-シャルを日本語授業で使用する際に, 學習者に起こりうる問題点とその對處法を考察する. TVコマ-シャルを使用した活動において. 問題が起こりうる學習者を「パニック型」と「耳すまし型」に分類し, 學習者がそれらの問題を克服するための對處法を考える. 最終章では, 學習者の視覺, 聽覺を通じた認識の仕組みについて, これからの硏究課題となる点が示唆される.

Spin Thermal Hall Conductivity of a Kagome Antiferromagnet

Doki, Hayato,Akazawa, Masatoshi,Lee, Hyun-Yong,Han, Jung Hoon,Sugii, Kaori,Shimozawa, Masaaki,Kawashima, Naoki,Oda, Migaku,Yoshida, Hiroyuki,Yamashita, Minoru American Physical Society 2018 Physical Review Letters Vol.121 No.9

$C_{x}F_{y}$ Polymer Film Deposition in rf and dc $C_{7}F_{16}$ Vapor Plasmas

Sakai, Y.,Akazawa, M.,Sakai, Yosuke,Sugawara, H.,Tabata, M.,Lungu, C.P.,Lungu, A.M. The Korean Institute of Electrical and Electronic 2001 Transactions on Electrical and Electronic Material Vol.2 No.1

$C_{x}F_{y}$ polymer film was deposited in rf and dc Fluorinert vapor ($C_{7}F_{16}$) plasmas. In the plasma phase, the spatial distribution of optical emission spectra and the temporal concentration of decomposed species were monitored, and kinetics of the $C_{7}F_{16}$ decomposition process was discussed. Deposition of $C_{x}F_{y}$ film has been tried on substrates of stainless steel, glass, molybdenum and silicon wafers at room temperature in the vapor pressures of 40 and 100 Pa. The films deposited in the rf plasma showed excellent electrical properties as an insulator for multi-layered interconnection of deep-submicron LSI, i.e. the low dielectric constant ∼2.0, the dielectric strength ∼2 MV/cm and the high deposition rate ∼100nm/min at 100W input power.

Accuracy of Pedicle Screw Placement in Scoliosis Surgery: A Comparison between Conventional Computed Tomography-Based and O-Arm-Based Navigation Techniques

Toshiaki Kotani,Tsutomu Akazawa,Tsuyoshi Sakuma,Kayo Koyama,Tetsuharu Nemoto,Kento Nawata,Atsuro Yamazaki,Shohei Minami 대한척추외과학회 2014 Asian Spine Journal Vol.8 No.3

Study Design: Retrospective study. Purpose: We compared the accuracy of O-arm-based navigation with computed tomography (CT)-based navigation in scoliotic surgery. Overview of Literature: No previous reports comparing the results of O-arm-based navigation with conventional CT-based navigation in scoliotic surgery have been published. Methods: A total of 222 pedicle screws were implanted in 29 patients using CT-based navigation (group C) and 416 screws were implanted in 32 patients using O-arm-based navigation (group O). Postoperative CT was performed to assess the screw accuracy, using the established Neo classification (grade 0: no perforation, grade 1: perforation <2 mm, grade 2: perforation ≥2 and <4, and grade 3: perforation ≥4 mm). Results: In group C, 188 (84.7%) of the 222 pedicle screw placements were categorized as grade 0, 23 (10.4%) were grade 1, 11 (5.0%) were grade 2, and 0 were grade 3. In group O, 351 (84.4%) of the 416 pedicle screw placements were categorized as grade 0, 52 (12.5%) were grade 1, 13 (3.1%) were grade 2, and 0 were grade 3. Statistical analysis showed no significant difference in the prevalence of grade 2–3 perforations between groups C and O. The time to position one screw, including registration, was 10.9±3.2 minutes in group C, but was significantly decreased to 5.4±1.1 minutes in group O. Conclusions: O-arm-based navigation facilitates pedicle screw insertion as accurately as conventional CT-based navigation. The use of O-arm-based navigation successfully reduced the time, demonstrating advantages in the safety and accuracy of pedicle screw placement for scoliotic surgery.

Current Transport, Fermi Level Pinning, and Transient Behavior of Group-III Nitride Schottky Barriers

Hideki Hasegawa,Masamichi Akazawa 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.55 No.3

The current transport, Fermi level pinning and transient behavior of Group-III nitride Schottky barriers are reviewed. First, an overview of interface models is given. Then, the current transport mechanism in GaN, AlGaN, and InGaN Schottky barriers is discussed. We show that discrepancy in barrier height measurements in the I-V and the C-V methods, as well as large reverse leakage currents, can be explained by using the thin surface barrier (TSB) model. This understanding has led to a large leakage reduction by using an oxygen gettering process. Finally, the transient behavior of AlGaN/ GaN planar Schottky diodes is discussed to get insight into the surface-related current collapse phenomenon in AlGaN/GaN high electron mobility transistors (HEMTs). The responses are explained in terms of the dispersive transport caused by a time-continual random walk with hopping through surface states. This provides a new understanding of the current collapse. The current transport, Fermi level pinning and transient behavior of Group-III nitride Schottky barriers are reviewed. First, an overview of interface models is given. Then, the current transport mechanism in GaN, AlGaN, and InGaN Schottky barriers is discussed. We show that discrepancy in barrier height measurements in the I-V and the C-V methods, as well as large reverse leakage currents, can be explained by using the thin surface barrier (TSB) model. This understanding has led to a large leakage reduction by using an oxygen gettering process. Finally, the transient behavior of AlGaN/ GaN planar Schottky diodes is discussed to get insight into the surface-related current collapse phenomenon in AlGaN/GaN high electron mobility transistors (HEMTs). The responses are explained in terms of the dispersive transport caused by a time-continual random walk with hopping through surface states. This provides a new understanding of the current collapse.

Biochemical and histo-morphometrical analyses of bone and cartilage induced by human decalcified dentin matrix and BMP-2

( Masaru Murata ),( Toshiyuki Akazawa ),( Junichi Hino ),( Junichi Tazaki ),( Katsutoshi Ito ),( Makoto Arisue ),( Maxillofacial Surgery ) 조선대학교 치의학연구원 2011 Oral Biology Research (Oral Biol Res) Vol.35 No.1

The aim of this study was to evaluate the hard tissue-inductive capability by human decalcified dentin matrix (DDM) with or without recombinant human bone morphogenetic protein-2 (BMP-2). Human teeth were crushed, completely decalcified and freeze-dried. We named the material DDM. The shape of DDM was a particle type and its size varied from 0.4 to 0.8 mm. The hard tissue induction by 70 mg of DDM was estimated histologically in the nude mice subcutaneous tissue at 4 weeks after implantation. The DDM alone induced bone and cartilage, independently, in the back skin. In addition, the time-course of bone induction by BMP-2 (5.0 μg)/DDM (70 mg) was analyzed in the rat subcutaneous tissues. Histological findings showed that the BMP-2/DDM induced bone and marrow between the DDM particles. Calcium content in the BMP-2/DDMinduced tissue was compatible to the histological findings. The morphometric analysis demonstrated that the BMP-2/DDM showed 66.9%, 79.0% in the volume of bone and marrow, and 32.4%, 21.0% in that of DDM at 8, 32 weeks, respectively. These results indicate that human DDM particles are osteo-chondroinductive and absorbable matrics. Human DDM are effective biomaterials of BMP-2 delivering for bone engineering.