Visualization of Skilled Worker Motion and its Effect on Product Quality and the Design of Skill Training Systems in Metallic Painting Operations

Masaki Kubo,Takuya Hida,Ryosuke Nakajima,Toshiyuki Matsumoto 대한산업공학회 2019 Industrial Engineeering & Management Systems Vol.18 No.1

Many tasks are currently automated in the manufacturing field, but some are still performed by workers, which require technical knowledge and skills. However, it is difficult for a new worker to learn skills that require precise motion and extensive experience. Conventional on-the-job training (OJT) has a problem, which is the difficulty of defining and evaluating a correct task. Therefore, this study aimed to visualize the proper skills and their effects on quality in metallic painting operations, and to design the concept for a skill training system. Product quality depends on a worker’s motion and the effects of tools. To train a skill based on these factors, it is necessary to visualize the proper skill and to devise a method of training. Therefore, changes to a worker’s motion and the quality of products were visualized using a motion capture (MOCAP) system and three-dimensional computer graphics (3DCG) software. Furthermore, such a system requires a trainee to experience the proper motion and to evaluate his or her skills. The motion of two skilled workers was therefore analyzed to extract their skills as explicit knowledge. The skilled workers’ motion was measured using the MOCAP system. The obtained data were then analyzed as positional and rotational data in three axes for each motion of the main parts of the body. Consequently, 11 types of skills were extracted by analyzing the data. Then, an experiment was conducted to visualize the quality of the metallic painting operation using film thickness as an index. Seven factors for film thickness were extracted, and these were quantified in the experiment. Moreover, these factors were applied to 3DCG, and the film thickness was reproduced by simulation. As the result of a statistical test, the reproducibility of the film thickness was guaranteed in 3DCG. Based on the results, a training system was designed for to enable a new worker to learn the skill.

QUASI-PASSIVE MOS FREQUENCY-TO-VOLTAGE AND VOLTAGE-TO-FREQUENCY CONVERTERS

Hiroki Matsumoto,Masaki Natsume 대한전자공학회 1989 JTC-CSCC : Joint Technical Conference on Circuits Vol.- No.-

Diffusion Tensor Imaging of the Spinal Canal in Quantitative Assessment of Patients with Lumbar Spinal Canal Stenosis

Norimoto Masaki,Eguchi Yawara,Kanamoto Hirohito,Oikawa Yasuhiro,Matsumoto Koji,Masuda Yoshitada,Furuya Takeo,Orita Sumihisa,Inage Kazuhide,Maki Satoshi,Shiga Yasuhiro,Kinoshita Hideyuki,Abe Koki,Inoue 대한척추외과학회 2021 Asian Spine Journal Vol.15 No.2

Study Design: Retrospective observational study. Purpose: Lumbar spinal stenosis (LSS) has traditionally been evaluated morphologically, there is a paucity of literature on quantitative assessment of LSS. The purpose of this study was to investigate whether intraspinal diffusion tensor imaging (DTI) parameters such as apparent diffusion coefficient (ADC) and fractional anisotropy (FA) are useful for assessing LSS. Overview of Literature: Quantitative assessment of LSS is challenging. Methods: Study participants comprised five healthy volunteers (mean age, 27.2 years) and 27 patients with LSS (mean age, 58.4 years) who were individually assessed using 3.0 Tesla magnetic resonance imaging. Intraspinal ADC and FA values of 10 intervertebral discs from healthy volunteers and 52 intervertebral discs from LSS patients were measured. Also, intraspinal canal area, Schizas classification (A: normal, B: mild stenosis, C: severe stenosis) and correlations with symptoms were investigated. Clinical symptoms were checked for the presence of low back pain (LBP), intermittent claudication (IMC), and bladder and bowel dysfunction (BBD). Results: Compared to healthy individuals, LSS patients had significantly lower ADC (p <0.05) and significantly higher FA values (p <0.01). In Schizas classification, stenosis worsened from A to C. ADC values decreased significantly while FA values increased significantly in that order (p <0.05). A positive correlation was found between intraspinal canal area and ADC values (r =0.63, p <0.01) and a negative correlation between intraspinal canal area and FA values (p =−0.61, p <0.01). No correlations were noted between LBP and ADC or FA values. On the other hand, ADC values were significantly lower (p <0.05) and FA values were significantly higher (p <0.05) in patients with IMC or BBD. Conclusions: Intraspinal DTI parameters such as ADC and FA values were associated with the Schizas classification, intraspinal canal area, and clinical symptoms, suggesting that ADC and FA may be useful for quantitative assessment of LSS.

A DIGITAL CAPACITANCE COMPARATOR

Hiroki Matsumoto,Masaki Natsume 대한전자공학회 1989 JTC-CSCC : Joint Technical Conference on Circuits Vol.- No.-

Quantitative Approaches to Assess Key Carcinogenic Events of Genotoxic Carcinogens

Shoji Fukushima,Min Gi,Masaki Fujioka,Anna Kakehashi,Hideki Wanibuchi,Michiharu Matsumoto 한국독성학회 2018 Toxicological Research Vol.34 No.4

Chemical carcinogenesis is a multistep process. Genotoxic carcinogens, which are DNA-reactive, induce DNA adduct formation and genetic alterations in target cells, thereby generating mutated cells (initiation). Subsequently, preneoplastic lesions appear through clonal proliferation of the mutated cells and transform into tumors (promotion and progression). Many factors may influence these processes in a dose-dependent manner. Therefore, quantitative analysis plays an important role in studies on the carcinogenic threshold of genotoxic carcinogens. Herein, we present data on the relationship between key carcinogenic events and their deriving point of departure (PoD). Their PoDs were also compared to those of the carcinogenesis pathway. In an experiment, the liver of rats exposed to 2-amino-3,8-dimethylimidazo-(4,5-f)quinoxaline (MeIQx) was examined to determine the formation of MeIQx-DNA adducts, generation of mutations at LacI transgene, and induction of preneoplastic glutathione S-transferase placental form (GST-P)-positive foci and tumors (benign and malignant). The PoDs of the above key events in the carcinogenicity of MeIQx were increased as the carcinogenesis advanced; however, these PoDs were lower than those of tumor induction. Thus, the order of key events during tumor induction in the liver was as follows: formation of DNA adducts ≪ Mutations ≪ GST-positive foci (preneoplasia) ≪ Tumor (adenoma and carcinoma). We also obtained similar data on the genotoxic and carcinogenic PoDs of other hepatocarcinogens, such as 2-amino-3,8-dimethylimidazo(4,5-f)quinoline. These results contribute to elucidating the existence of a genotoxic and carcinogenic threshold.

Evaluating Spinal Canal Lesions Using Apparent Diffusion Coefficient Maps with Diffusion-Weighted Imaging

Kanamoto Hirohito,Norimoto Masaki,Eguchi Yawara,Oikawa Yasuhiro,Orita Sumihisa,Inage Kazuhide,Abe Koki,Inoue Masahiro,Kinoshita Hideyuki,Umimura Tomotaka,Matsumoto Koji,Masuda Yoshitada,Furuya Takeo,K 대한척추외과학회 2020 Asian Spine Journal Vol.14 No.3

Study Design: Observational study.Purpose: To evaluate healthy volunteers and patients with spinal canal lesions using apparent diffusion coefficient (ADC) maps with diffusion-weighted imaging.Overview of Literature: Decompression surgery for lumbar spinal stenosis (LSS) is selected on the basis of subjective assessment and cross-sectional magnetic resonance imaging (MRI). However, there is no objective standard for this procedure.Methods: We performed 3T MRI in 10 healthy volunteers and 13 patients with LSS. The ADC values in the spinal canal were evaluated at 46 vertebrae (L4/5 and L5/S1 for each participant), and the reduced and conventional fields of view were compared.Results: The ADC values were 2.72±0.12 at L4/5 in healthy volunteers, 2.76±0.19 at L5/S1 in healthy volunteers, 1.77±0.58 at L4/5 in patients with LSS, and 2.35±0.29 at L5/S1 in patients with LSS. The ADC value at L4/5 in patients with LSS was significantly lower than that at L5/S1 in patients with LSS and that at L4/5 and L5/S1 in healthy volunteers (<i>p</i> <0.05). With an ADC cutoff value of 2.46 to identify LSS, this approach provided an area under the curve of 0.81, sensitivity of 0.92, and specificity of 0.76 (<i>p</i> <0.05).Conclusions: Preoperative examination using ADC maps permits visualization and quantification of spinal canal lesions, thus proving the utility of ADC maps in the selection of decompression surgery for LSS.

Whole body vibration accelerates the functional recovery of motor nerve components in sciatic nerve-crush injury model rats

Atsushi Doi,Kyoka Oda,Masaki Matsumoto,Honoka Sakoguchi,Mizuki Honda,Yuma Ogata,Asuka Nakano,Misato Taniguchi,Shunya Fukushima,Kyogo Imayoshi,Kanta Nagao,Masami Toyoda,Hiroki Kameyama,Motoki Sonohata 한국운동재활학회 2023 JER Vol.19 No.3

Effect of Stagger Angle on the Three-Dimensional Separation Around a NACA65 Blade in a Decelerating Flow

Yoichi Kinoue,Yuya Matsumoto,Masaki Sakaguchi,Norimasa Shiomi 한국유체기계학회 2021 International journal of fluid machinery and syste Vol.14 No.1

In order to examine the fundamental characteristics of a corner separation in a decelerating cascade flow, an experimental apparatus was made and the three-dimensional separation around a NACA65 blade in a decelerating channel flow was investigated experimentally. Effect of stagger angle of 14 deg. and 10 deg. on the channel flow was focused on. The experimental investigation by the five-hole probe showed that the accumulations of the low energy fluid was seen around the corner part and the overturning flow due to the secondary flow existed for 14 deg. of stagger angle, whereas the accumulations of the low energy fluid were seen at around midspan for 10 deg. of stagger angle. PIV measurement showed that various focus-type separations were seen in the flow for 10 deg. of stagger angle and three-dimensional vortex structure was considered by using a vortex filament.

Inhaled Corticosteroid and Secondary Glaucoma: A Meta-analysis of 18 Studies

Ishii Mai,Horita Nobuyuki,Takeuchi Masaki,Matsumoto Hiromi,Ebina-Shibuya Risa,Hara Yu,Kobayashi Nobuaki,Mizuki Nobuhisa,Kaneko Takeshi 대한천식알레르기학회 2021 Allergy, Asthma & Immunology Research Vol.13 No.3

Purpose Guidelines and systematic reviews frequently warn of inhaled corticosteroid (ICS)-induced glaucoma. However, most of the published studies deny it. Methods We performed a systematic review of randomized, cohort, nested-case control, cross-sectional studies by using Meta-analyses of Observational Studies in Epidemiology statement. Four major databases, PubMed, EMBASE, Cochrane Search Manager, and the Web of Science Core Collection as well as meta-analysis were used. Studies comparing incidence, prevalence and intraocular pressure (IOP) between patients who were treated with and without ICSs were included. A random-model meta-analysis was performed using the inverse variance method. Results Out of 623 studies screened, 18 with 31,665 subjects were finally included. No significant difference between the 2 groups was observed for crude glaucoma incidence (odds ratio [OR], 0.95; 95% confidence interval [CI], 0.86–1.04; P = 0.26; I 2 = 0%; P for heterogeneity = 0.57) as a primary endpoint, adjusted glaucoma incidence (OR, 0.90; 95% CI, 0.65–1.24; P = 0.64), crude prevalence (OR, 1.82; 95% CI, 0.23–14.19; P = 0.57), adjusted prevalence (OR, 1.22; 95% CI, 0.50–2.96; P = 0.66), IOP change during ICS treatment (mean difference [MD] +0.01 mmHg; 95% CI, −0.19–0.20; P = 0.95), and single measurement IOP (MD +0.37 mmHg; 95% CI, −0.24–0.97; P = 0.23). Time-to-event analysis for glaucoma development as one of the secondary endpoints (adjusted hazard ratio, 0.52; 95% CI, 0.28–0.96) suggested a reverse association between ICS and glaucoma. Conclusions The ophthalmological side effects of ICSs, such as glaucoma and intraocular hypertension, should not be exaggerated.

Efficacy and safety of cold forceps polypectomy utilizing the jumbo cup: a prospective study

( Hiroshi Hasegawa ),( Shigeki Bamba ),( Kenichiro Takahashi ),( Masaki Murata ),( Taketo Otsuka ),( Hiroshi Matsumoto ),( Takehide Fujimoto ),( Rie Osaki ),( Hirotsugu Imaeda ),( Atsushi Nishida ),( 대한장연구학회 2019 Intestinal Research Vol.17 No.2

Background/Aims: There are few prospective studies on cold forceps polypectomy (CFP) using jumbo cup forceps. Therefore, we examined patients with diminutive polyps (5 mm or smaller) treated with CFP using jumbo cup forceps to achieve an ade-noma-free colon and also assessed the safety of the procedure and the recurrence rate of missed or residual polyp after CFP by performing follow-up colo-noscopy 1 year later. Methods: We included patients with up to 5 adenomas removed at initial colonoscopy and analyzed data from a total of 361 patients with 573 adenomas. One-year follow-up colonoscopy was performed in 165 patients, at which 251 lesions were confirmed. Results: The one-bite resection rate with CFP was highest for lesions 3 mm or smaller and decreased significantly with increasing lesion size. Post-procedural hemorrhage was observed in 1 of 573 lesions (0.17%). No perforation was noted. The definite recurrence rate was 0.8% (2/251 lesions). The probable recurrence rate, which was defined as recurrence in the same colorectal segment, was 17%. Adenoma-free colon was achieved in 55% of patients at initial resection. Multivariate analysis revealed that achievement of an adenoma-free colon was significantly associated with number of adenomas and years of endoscopic experience. Conclusions: CFP using jumbo biopsy forceps was safe and showed a high one-bite resection rate for diminutive lesions of 3 mm or smaller. The low definite recurrence rate confirms the reliability of CFP using jumbo biopsy forceps. Number of adenomas and years of endoscopic experience were key factors in achieving an adenoma-free colon. (Intest Res 2019;17:265-272.)