Non-Flying-Type MEID Mechanism for Lunar/Planetary Exploration Spacecraft Landing

Susumu Hara,Shintaro Matsui,Naoaki Saeki,Masatsugu Otsuki 대한기계학회 2015 대한기계학회 춘추학술대회 Vol.춘계 No.-

In these days, lunar/planetary detailedv exploration attracts attention again. When lunar/planetary exploration spacecraft land, large shock force may suspend them from continuing the mission by damages to mounted devices. Additionally, its shock caused spacecraft to rebound and tip over, and highly precise explorations become hard. Therefore novel landing methods to lunar/planetary surface are needed to be developed. Inprevious studies, the authors’ research group proposed the shock response control methods on the basis of momentum exchange principles. Conceretely, they adopted momentum exchange impact dampers (MEIDs) that exchange the controlled object’s momentum for that of extra masses (damper masses) close to the object. However, flying damper masses may reshock to the spacecraft or pollute the lunar/planetary surface. Therefore, the authors discuss Non-Flying-Type MEID (NFMEID) mechanism in this paper. NFMEID mechanism can exchange a part of the shock in landing for the rotary momentum of the damper masses and landing gear. If this type is available, MEID mechanisms can be applied to not only spacecraft but also general mechanical structures. The usefulness of MEID mechanism may be dramatically extended. This paper shows the effectiveness of NFMEID mechanism by some falling simulations.

Experimental Study on Low-Speed Control for Motorcycles Using SPACAR Model and Gain-Scheduling Control

Hara Susumu,Tsuchiya Mitsuo,Kimura Tetsuya,Akai Naoki 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.3

Recently, many studies have presented on realizing novel mobility technologies with consideration for aging society. The aim of these studies is to establish autonomous driving technology (ADT). The objects of ADT are mainly four-wheel motor vehicles. On the other hand, ADT for motorcycles has not been fully addressed yet. Motorcycles have straight-line stability in the state of high-speed driving. However, their stability tends to diminish when being driven at extremely low speed. This study addresses how a motorcycle should be stabilized under low-speed driving. From the viewpoint of actual use, including high-speed driving, major structural changes should be avoided. In order to obtain a linearized motorcycle model without skidding, a model based on SPACAR, a finite element method computation program, is introduced. Furthermore, velocity-dependent gain-scheduling control is applied to utilize the feedback control gains obtained by the linearized model with respect to velocity. Following the deceleration simulation success in the authors’ previous paper, we mainly verify the experimental investigation of the above model and control system design. The gain-scheduling method is improved from that in the previous simulation study. The experimental responses show stable driving at 1.5 km/h.

Identification of Arsenic Speciation and Accumulated Organic Species in Different Environment of Organic Sedimentation

Junko Hara,Susumu Norota,Yasuyuki Kakihara,Yoshishige Kawabe,Ming Zhang 한국토양비료학회 2014 한국토양비료학회 학술발표회 초록집 Vol.2014 No.6

Review : EUS-Guided Biliary Drainage

( Kenji Yamao ),( Kazuo Hara ),( Nobumasa Mizuno ),( Akira Sawaki ),( Susumu Hijioka ),( Yasumasa Niwa ),( Masahiro Tajika ),( Hiroki Kawai ),( Shinya Kondo ),( Yasuhiro Shimizu ),( Vikram Bhatia ) The Editorial Office of Gut and Liver 2010 Gut and Liver Vol.4 No.s1

Endoscopic ultrasonography (EUS) combines endoscopy and intraluminal ultrasonography, and allows imaging with a high-frequency transducer over a short distance to generate high-resolution ultrasonographic images. EUS is now a widely accepted modality for diagnosing pancreatobiliary diseases. EUS-guided fineneedle aspiration (EUS-FNA) using a curved linear- array echoendoscope was initially described more than 20 years ago, and since then many researchers have expanded its indications to sample diverse lesions and have also used it for various therapeutic purposes. EUS-guided biliary drainage (EUS-BD) is one of the therapeutic procedures that has been developed using a curved linear-array echoendoscope. Technically, EUS-BD includes rendezvous techniques via transesophageal, transgastric, and transduodenal routes, EUS-guided choledochoduodenostomy (EUS-CDS), and EUS-guided hepaticogastrostomy (EUS-HGS). Published data have demonstrated a high success rate, albeit with a comparatively high rate of nonfatal complications for EUS-CDS and EUS-HGS, and a comparatively low success rate with a low complication rate for the rendezvous technique. At present, these procedures represent an alternative to surgery or percutaneous transhepatic biliary drainage (PTBD) for patients with obstructive jaundice when endoscopic biliary drainage (EBD) has failed. However, these procedures should be performed in centers with extensive experience in linear EUS and therapeutic biliary ERCP. Large prospective studies are needed in the near future to establish standardized EUS-BD procedures as well as to perform controlled comparative trials between EUS-BD and PTBD, between rendezvous techniques and direct-access techniques (EUS-CDS and EUS-HGS), and between EBD and EUS-BD. (Gut Liver 2010;4(Suppl. 1):S67-75)

Are Newer Extracorporeal Shock Wave Lithotripsy Models Truly Improving Pancreatolithiasis Lithotripsy Performance? A Japanese Single-Center Study Using Endoscopic Adjunctive Treatment

Ito Ken,Okano Naoki,Takuma Kensuke,Iwasaki Susumu,Watanabe Koji,Kimura Yusuke,Yamada Yuto,Yoshimoto Kensuke,Hara Seiichi,Kishimoto Yui,Matsuda Takahisa,Igarashi Yoshinori 거트앤리버 소화기연관학회협의회 2023 Gut and Liver Vol.17 No.4

Background/Aims: Many Japanese institutions use electromagnetic extracorporeal shock wave lithotripsy (ESWL) systems for treating pancreatic duct stones. However, there are no reports on direct comparisons between recent electromagnetic lithotripters. This study aimed to verify whether the new electromagnetic lithotripter can improve the efficiency of pancreatic stone fragmentation, and to clarify the role of combined endoscopic treatment on the clearance of pancreatic duct stones. Methods: We retrospectively identified 208 patients with pancreatolithiasis who underwent endoscopic adjunctive treatment after pancreatic ESWL at a single Japanese center over a 17-year period. We evaluated the outcome data of this procedure performed with SLX-F2 (last 2 years; group A) and Lithostar/Lithoskop (first 15 years; group B), as well as additional endoscopic treatments for pancreatolithiasis. We also performed logistic regression analysis to detect various factors associated with the procedure. Results: For pancreatic head stones, ESWL disintegration was achieved in 93.7% of group A patients and 69.0% of group B patients (p=0.004), and adjunctive endoscopic treatment removed stones in 96.8% of group A patients and 73.0% of group B patients (p=0.003). Multivariate analysis revealed that lithotripter type (odds ratio, 6.99; 95% confidence interval, 1.56 to 31.33; p<0.01) and main pancreatic duct stricture (odds ratio, 2.87; 95% confidence interval, 1.27 to 6.45; p<0.01) were significant factors for ESWL fragmentation. Conclusions: The SLX F2 showed high performance in fragmenting the pancreatic duct stones. In addition, endoscopic adjunctive treatment improved the overall success rate of the procedure. The improved ESWL lithotripter has many advantages for patients undergoing pancreatic lithotripsy treatment.

Semi-Active Operation Assist Control Device for Manual Conveyance of Flexible Parts

Kensuke Yamaguchi,Michihiro Takeshige,Noritaka Sato,Yoshifumi Morita,Hiroyuki Ukai,Susumu Hara 제어로봇시스템학회 2012 제어로봇시스템학회 국제학술대회 논문집 Vol.2012 No.10

This paper proposes an assist-handle for manual conveyance of flexible part and its semi-active operation assist control. The assist-handle consists of a handle, a variable damper and a mechanical spring. The variable damper and the mechanical spring are connected in parallel. The assist-handle can be attached to a general hand cart, through which a human operates the hand cart. In order to suppress the vibration of the flexible part, the operating force is shaped by changing the viscosity of variable damper. Then the shaped force is transmitted to the hand cart through the assist-handle. The controlled system, which consists of the assist-handle, a hand cart and a flexible part, is represented as a bilinear system. The semi-active operation assist control is designed by using the bilinear optimal control theory. The performance index of bilinear optimal control involves the vibration of the flexible part and the control input. The effectiveness of the assist-handle and the semi-active operation assist control is verified by simulations.

Enhanced electrochemical strain in polypyrrole films

Takaharu Nakashima,Devendra Kumar,Wataru Takashima,Tetsuji Zama,Susumu Hara,Shingo Sewa,Keiich Kaneto 한국물리학회 2005 Current Applied Physics Vol.5 No.2

Electrochemomechanical characteristics of polypyrrole (PPy) lms, electrodeposited from tetra-n-butylammonium triuorometh-ane-sulfonate dissolved in methyl benzoate (PPyFMS), have been investigated using a simultaneous measurement of electrochem-omechanical deformation (ECMD) with cyclic voltammetry (CV) by comparing with PPy lms deposited fromp-phenol sulfonate inaqueous media (PPyPPS). The ECMD magnitude of PPyFMS lm was reached around 9% at 1st cycle and was decreased to beabout 3.2% at 20th cycle with electrochemical cycling in 1 M NaPF6. While in 1 M NaCl solution, the ECMD magnitude was1.9% at 20th cycle in CV measurement. In the case for the PPyPPS lm, ECMD magnitude at 20th cycle was around 0.8% and1.1% in 1 M NaPF 6 and 1 M NaCl solutions, respectively. The results indicate that the combination of electrolytes employed inboth the electrodeposition and the device actuation plays the very important role for achieving the enhancement of ECMD magn-itudes. In the case of ECMD behaviors, it was found that the electrolyte used in the lm actuation determines the ECMD charac-teristics..

Peroral Pancreatoscopy with Videoscopy and Narrow-Band Imaging in Intraductal Papillary Mucinous Neoplasms with Dilatation of the Main Pancreatic Duct

Yui Kishimoto,Naoki Okano,Ken Ito,Kensuke Takuma,Seiichi Hara,Susumu Iwasaki,Kensuke Yoshimoto,Yuto Yamada,Koji Watanabe,Yusuke Kimura,Hiroki Nakagawa,Yoshinori Igarashi 대한소화기내시경학회 2022 Clinical Endoscopy Vol.55 No.2

Background/Aims: Endoscopic evaluation of intraductal papillary mucinous neoplasms (IPMNs) is useful in determining whetherthe lesions are benign or malignant. This study aimed to examine the usefulness of peroral pancreatoscopy (POPS) in determiningthe prognosis of IPMNs. Methods: POPS with videoscopy was performed using the mother–baby scope technique. After surgery, computed tomography/magnetic resonance cholangiopancreatography or ultrasonography and blood tests were performed every 6 months during thefollow-up. Results: A total of 39 patients with main pancreatic duct (MPD)–type IPMNs underwent POPS using a videoscope, and theprotrusions in the MPD were observed in 36 patients. The sensitivity and specificity of cytology/biopsy performed at the time ofPOPS were 85% and 87.5%, respectively. Of 19 patients who underwent surgery, 18 (95%) patients had negative surgical margins and1 (5%) patient had a positive margin. Conclusions: In IPMNs with dilatation of the MPD, POPS is considered effective if the lesions can be directly observed. Thediagnosis of benign and malignant lesions is possible depending on the degree of lesion elevation. However, in some cases, slightlyelevated lesions may increase in size during the follow-up or multiple lesions may be simultaneously present; therefore, carefulfollow-up is necessary.

Efficacy of Hypertonic Saline-Epinephrine Local Injection Around the Anal Side before Endoscopic Papillectomy for Ampullary Tumors

Naoki Okano,Yoshinori Igarashi,Ken Ito,Saori Mizutani,Hiroki Nakagawa,Kouji Watanabe,Yuuto Yamada,Kensuke Yoshimoto,Yuusuke Kimura,Susumu Iwasaki,Kensuke Takuma,Seiichi Hara,Yuui Kishimoto 대한소화기내시경학회 2021 Clinical Endoscopy Vol.54 No.5

Background/Aims: Bleeding is a complication of endoscopic snare papillectomy for ampullary tumors. This study aimed toinvestigate the clinical efficacy of hypertonic saline-epinephrine (HSE) local injection before endoscopic papillectomy for preventionof bleeding. Methods: We retrospectively reviewed the data of 107 consecutive patients with ampullary tumors who underwent endoscopicpapillectomy. The rates of en bloc resection, pathological resection margins, and prevention of immediate or delayed bleeding in thesimple snaring resection group (Group A) and the HSE injection group (Group B) were compared. Results: A total of 44 and 63 patients were enrolled in Groups A and B, respectively. The total complete resection rate was 89.7%(96/107); the clinical complete resection rates in Group A and Group B were 86.3% (38/44) and 92.1% (58/63), respectively (p=0.354). Post-papillectomy bleeding occurred in 22 patients. In Groups A and B, the immediate bleeding rates were 20.5% (9/44) and 4.8%(3/63), respectively (p=0.0255), while the delayed bleeding rates were 7% (3/44) and 11% (7/63), respectively (p=0.52). The rates ofpositive horizontal and vertical pathological margin in both groups were 27% and 16%, respectively. Conclusions: HSE local injection was effective in preventing immediate bleeding and was useful for safely performing endoscopicpapillectomy for ampullary tumors.