A Design of FIR Filter Using CSD with Minimum Number of Registers

Suzuki, Kenichi,Ochi, Hiroshi,Kinjo, Shigenori 대한전자공학회 1996 APCCAS:Asia Pacific Conference on Circuits And Sys Vol.1 No.1

This paper proposes an algorithm to be used for VLSI design of FIR filter using a canonical signed digit (CSD) representation with a minimum number of registers. The coefficients represented by CSD have a common digit pattern, so that they can reduce the number of adders to calculate same digit patterns. The proposed method takes advantage of this technique without using more registers than that of the transfer function.

A PRELIMINARY EVALUATION OF UNPROTECTED LOSS-OF-FLOW ACCIDENT FOR A PROTOTYPE FAST-BREEDER REACTOR

TOHRU SUZUKI,Yoshiharu Tobita,KENICHI KAWADA,HIROTAKA TAGAMI,JOJI SOGABE,KENICHI MATSUBA,KEI ITO,HIROYUKI OHSHIMA 한국원자력학회 2015 Nuclear Engineering and Technology Vol.47 No.3

In the original licensing application for the prototype fast-breeder reactor, MONJU, the event progression during an unprotected loss of flow (ULOF), which is one of the technically inconceivable events postulated beyond design basis, was evaluated. Through this evaluation, it was confirmed that radiological consequences could be suitably limited even if mechanical energy was released. Following the Fukushima-Daiichi accident, a new nuclear safety regulation has become effective in Japan. The conformity of MONJU to this new regulation should hence be investigated. The objectives of the present study are to conduct a preliminary evaluation of ULOF for MONJU, reflecting the knowledge obtained after the original licensing application through CABRI experiments and EAGLE projects, and to gain the prospect of in-vessel retention for the conformity of MONJU to the new regulation. The preliminary evaluation in the present study showed that no significant mechanical energy release would take place, and that thermal failure of the reactor vessel could be avoided by the stable cooling of disrupted-core materials. This result suggests that the prospect of in-vessel retention against ULOF, which lies within the bounds of the original licensing evaluation and conforms to the new nuclear safety regulation, will be gained.

Development and validation of fuel stub motion model for the disrupted core of a sodium-cooled fast reactor

Kenichi Kawada,Tohru Suzuki 한국원자력학회 2021 Nuclear Engineering and Technology Vol.53 No.12

To improve the capability of the SAS4A code, which simulates the initiating phase of core disruptiveaccidents for MOX-fueled Sodium-cooled Fast Reactors (SFRs), the authors have investigated in detail thephysical phenomena under unprotected loss-of-flow (ULOF) conditions in a previous paper (Kawada andSuzuki, 2020) [1]. As the conclusion of the last article, fuel stub motion, in which the residual fuel pelletswould move toward the core central region after fuel pin disruption, was identified as one of the keyphenomena to be appropriately simulated for the initiating phase of ULOF. In the present paper, based on the analysis of the experimental data, the behaviors related to the stubmotion were evaluated and quantified by the author from scratch. A simple model describing fuel stubmotion, which was not modeled in the previous SAS4A code, was newly proposed. The applicability ofthe proposed model was validated through a series of analyses for the CABRI experiments, by which thestub motion would be represented with reasonable conservativeness for the reactivity evaluation ofdisrupted core

Mucosal and Submucosal Thickening of Esophageal Wall Is a Promising Factor in the Development of Symptoms in Eosinophilic Esophagitis

Suzuki Yugo,Ochiai Yorinari,Hosoi Atsuko,Okamura Takayuki,Hayasaka Junnosuke,Mitsunaga Yutaka,Tanaka Masami,Odagiri Hiroyuki,Nomura Kosuke,Yamashita Satoshi,Matsui Akira,Kikuchi Daisuke,Ohashi Kenichi 거트앤리버 소화기연관학회협의회 2024 Gut and Liver Vol.18 No.1

Background/Aims: Asymptomatic esophageal eosinophilia (aEE) is considered to be a potential precursor of eosinophilic esophagitis (EoE). However, there are few clinical parameters that can be used to evaluate the disease. Therefore, we aimed to clarify the factors involved in the symptoms of EoE by examining the clinicopathological differences between aEE and EoE. Methods: We reviewed 41 patients with esophageal eosinophilia who underwent endoscopic ultrasonography and high-resolution manometry. They were divided into the aEE group (n=16) and the EoE group (n=25) using the Frequency Scale for the Symptoms of Gastroesophageal Reflux Disease score. The patients’ clinicopathological findings were collected and examined. Results: The median Frequency Scale for the Symptoms of Gastroesophageal Reflux Disease score was 3.0 in the aEE group and 10.0 in the EoE group. There was no significant difference in patient characteristics, endoscopic findings and pathological findings. The cutoff value for wall thickening was 3.13 mm for the total esophageal wall thickness and 2.30 mm for the thickness from the surface to the muscular layer (total esophageal wall thickness: 84.0% sensitivity, 75.0% specificity; thickness from the surface to the muscular layer: 84.0% sensitivity, 68.7% specificity). The high-resolution manometry study was abnormal in seven patients (43.8%) in the aEE group and in 12 (48.0%) in the EoE group. The contractile front velocity was slower in the EoE group (p=0.026). Conclusions: The esophageal wall thickening in the lower portion of the esophagus is an important clinical factors related to the symptoms in patients with EoE.

Distributed Control of Robot Functions using RT Middleware

Kenichi Ohara,Takashi Suzuki,Noriaki Ando,Bong Keun Kim 제어로봇시스템학회 2006 제어로봇시스템학회 국제학술대회 논문집 Vol.2006 No.10

Use of colony-stimulating factor in patients with ovarian cancer receiving paclitaxel and carboplatin in Japan

Kenichi Harano,Akihiro Hirakawa,Takayuki Kato,Keisuke Suzuki,Sachiko Watanabe,Noriyuki Katsumata 대한부인종양학회 2014 Journal of Gynecologic Oncology Vol.25 No.2

Objective: To assess the use of colony-stimulating factors (CSFs) in patients with ovarian cancer who receive adjuvant paclitaxel and carboplatin chemotherapy in clinical practice and to assess whether the frequency of CSF use differs among hospitals in Japan. Methods: CSF use in patients with ovarian cancer who received first-line paclitaxel and carboplatin was analyzed retrospectively using data from the Japanese hospitalization payment system. Results: A total of 1,050 patients at 104 hospitals were identified. The median age was 60 years (range, 22 to 88 years). Of these, 163 patients (15.5%) were diagnosed with neutropenia and 134 patients (12.8%) received CSFs. Among the patients who received CSFs, 125 (93%) received them for the treatment of neutropenia without fever and 1 received them for febrile neutropenia. In total, CSFs were administered for 272 cycles of chemotherapy. Among them, CSFs were used as treatment for neutropenia without fever in 259 cycles (95%), as prophylaxis (primary or secondary) in 12 cycles (4%), and as treatment for febrile neutropenia in 1 cycle. Among hospitals, a median of 4.0% of patients received CSFs with an interquartile range of 25% (Q1, 0%; Q3, 25%). A logistic random effects model showed that the variation in the proportion of patients receiving CSFs among the 104 hospitals was 2.0 (p<0.001), suggesting that the use of CSFs varied across hospitals. Conclusion: Most patients received CSFs for neutropenia without fever. Standardized and evidence-based use of CSFs is critically required among hospitals in Japan.

Long-term Outcome of Asymptomatic Esophageal Eosinophilia

( Yugo Suzuki ),( Yorinari Ochiai ),( Daisuke Kikuchi ),( Mako Koseki ),( Kenichi Ohashi ),( Shu Hoteya ) 대한소화기학회 2024 Gut and Liver Vol.18 No.4

Background/Aims: Asymptomatic esophageal eosinophilia (aEE), characterized by eosinophil infiltration in the esophagus without clinical symptoms, has been reported as a precursor of eosinophilic esophagitis (EoE). Nevertheless, no report exists on the long-term clinical course of the disease. Therefore, this study aimed to investigate the long-term clinical course of aEE over 5 years, including the symptomatic conversion rate and the effect of treatments. Methods: We reviewed 28 patients with aEE who had been followed up for over 5 years with endoscopic monitoring. The basal characteristics of patients were compared with those of 58 patients diagnosed with EoE during the same period. Patients’ clinicopathological findings were collected and examined. Results: No significant differences in basal characteristics and histopathological findings were observed between the patients with aEE and those with EoE. The median follow-up duration was 64 months. Among the 28 patients with aEE, seven were treated with proton pump inhibitor or potassium-competitive acid blocker and the remaining 21 opted for follow-up with no medication. Among the treated patients, six (85.7%) exhibited endoscopic and pathologic improvements. Among the cases followed up without medication, the findings worsened in two (9.5%), improved spontaneously in seven (33.3%), and were unchanged in 12 (57.1%), and three (14.3%) developed symptoms at a mean time of 40 months. Symptoms developed in cases where endoscopic and pathologic findings remained unchanged or worsened during follow-up. Conclusions: Some patients with aEE had improved findings without treatment, whereas others developed symptoms, emphasizing the importance of long-term monitoring and individualized treatment decisions. (Gut Liver 2024;18:632-641)

Properties of Chemical Beam Epitaxy grown GaAs0.995N0.005 homo-junction solar cell

Boussairi Bouzazi,Kenichi Nishimura,Hidetoshi Suzuki,Nobuaki Kojima,Yoshio Ohshita,Masafumi Yamaguchi 한국물리학회 2010 Current Applied Physics Vol.10 No.2

The minority carrier diffusion length in Chemical Beam Epitaxy (CBE) grown GaAs0.995N0.005 based homojunction solar cell was estimated and found to be L = 0.08 lm. In addition, the majority carrier traps in Nvarying unintentionally doped p-type GaAsN samples grown by CBE were investigated using Deep Level Transient Spectroscopy (DLTS) technique. Five hole traps, HC1–HC5, were detected, where HC2 and HC5coexist in all samples. These two hole traps were suggested to be a N-related defect and the double donor state of EL2, respectively.

Comparison of the Effects of Ezetimibe-Statin Combination Therapy on Major Adverse Cardiovascular Events in Patients with and without Diabetes: A Meta-Analysis

홍남기,이용호,Kenichi Tsujita,Jorge A. Gonzalez,Christopher M. Kramer,Tomas Kovarnik,George N. Kouvelos,Hiromichi Suzuki,한경도,이찬주,박성하,이병완,차봉수,강은석 대한내분비학회 2018 Endocrinology and metabolism Vol.33 No.2

Background: Ezetimibe-statin combination therapy has been found to reduce low density lipoprotein cholesterol levels and the risk of major adverse cardiovascular events (MACEs) in large trials. We sought to examine the differential effect of ezetimibe on MACEs when added to statins according to the presence of diabetes. Methods: Randomized clinical trials with a sample size of at least 50 participants and at least 24 weeks of follow-up that compared ezetimibe-statin combination therapy with a statin- or placebo-controlled arm and reported at least one MACE, stratified by diabetes status, were included in the meta-analysis and meta-regression. Results: A total of seven trials with 28,191 enrolled patients (mean age, 63.6 years; 75.1% men; 7,298 with diabetes [25.9%]; mean follow-up, 5 years) were analysed. MACEs stratified by diabetes were obtained from the published data (two trials) or through direct contact (five trials). No significant heterogeneity was observed among studies (I2=14.7%, P=0.293). Ezetimibe was associated with a greater reduction of MACE risk in subjects with diabetes than in those without diabetes (pooled relative risk, 0.84 vs. 0.93; Pheterogeneity=0.012). In the meta-regression analysis, the presence of diabetes was associated with a greater reduction of MACE risk when ezetimibe was added to statins (β=0.87, P=0.038). Conclusion: Ezetimibe-statin combination therapy was associated with greater cardiovascular benefits in patients with diabetes than in those without diabetes. Our findings suggest that ezetimibe-statin combination therapy might be a useful strategy in patients with diabetes at a residual risk of MACEs.

Development of Automatic Chatter Suppression System in Parallel Milling by Real-Time Spindle Speed Control with Observer-Based Chatter Monitoring

Shuntaro Yamato,Kenichi Nakanishi,Norikazu Suzuki,Yasuhiro Kakinuma 한국정밀공학회 2021 International Journal of Precision Engineering and Vol.22 No.2

To maximize the potential for high material removal rates in simultaneous processes such as parallel milling, developing strategies for successful chatter suppression/avoidance is an important concern for manufacturers. In this study, the effectiveness of the spindle speed difference method (SDM) for chatter suppression is discussed in a parallel end-milling process where a flexible workpiece is machined by two tools rotating in opposite direction. The process model is developed, considering that the dynamic variation due to the regenerative eff ect occurs on a plane perpendicular to the tool axis direction. Through the process simulations and the experiments, this study provides informative discussion for comprehending the process behavior. Additionally, a real-time active chatter suppression system with adaptive SDM, where the spindle speed difference is sequentially optimized during the process according to the tracked chatter frequency, is developed by integrating a chatter monitoring system based on sensorless cutting force estimation with sliding discrete Fourier transform. The results show that the developed real-time adaptive system of spindle speed suppresses chatter vibrations more effectively than non-adaptive SDM system; hence, the integrated system can contribute self-optimizing machining systems oriented to Industry 4.0.