580 research outputs found

    Gust Alleviation Control Using Robust MPC

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    Evaluation of contour of unruptured cerebral aneurysm using three-dimensional CT cisternogram.

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    Angiography is gold standard technique as preoperative examination for unruptured aneurysmal surgery. Neurosurgeons have observed the unexpected irregular shape and size of the aneurysmal dome and neck in many cases of unruptured cerebral aneurysms during aneurysmal microsurgery, and known the discrepancy between the findings of angiography and operative view. We could not find out the report described the preoperative evaluation of outer-wall (contour) of aneurysm. In the present study, we attempted to evaluate the outer-wall of an unruptured cerebral aneurysm using three-dimensional CT cisternogram (3D-CTC) to provide useful preoperative information. The study was performed on three cases of unruptured cerebral aneurysm that were identified incidentally by MR angiography. We performed three-dimensional CT aniography (3D-CTA) and 3D-CTC for each patient. In the present study, we visualized the contours of vessels and aneurysms using a 3D-CTC in three cases of unruptured cerebral aneurysm. We found the discrepancy between the 3D-CTC contour image and the intra-luminal image 3D-CTA image. This method may be useful for the decision of the surgical approach and have the potential to evaluate the anatomical structure of aneurysmal dome and neck preoperatively.</p

    NUMERICAL ANALYSIS ON MAGNETIC SHIELDING OF AXIALLY SYMMETRIC SUPERCONDUCTING PLATE

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    The effects of the superconducting plate shape on the magnetic shielding are investigated. The plate shape is assumed to be axially symmetric and the permeability of the plate is assumed non-zero. A numerical code to calculate the magnetostatic field around the plate is developed and the spatial distributions of the decay factors are calculated by means of the code. The results of computations show that the magnetic shielding becomes large with the increase of triangularity and with the decrease of ellipticity

    Japanese Irrigation Management at the Crossroads

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    To achieve the goals of irrigation projects, governments need to ensure appropriate operations and maintenance. The Japanese government has established a national-level participatory irrigation management (PIM) approach since 17th century and the Japanese farmers presently operate and maintain entire irrigation systems at their own cost under the Land Improvement Act enacted in 1949. However, whether this Japanese system is relevant to other countries remains unclear. This paper aims to characterise the PIM system in detail; it analyses its background conditions and extracts implications for successful PIM methodology. To that end, we mobilised and compared all relevant information regarding legal aspects, practices and statistics. We concluded that: 1) farmersā€™ involvement from the initial planning stages ā€“ which is a requirement of the Japanese governmentā€™s application system for irrigation projects ā€“ is critical if projects are to succeed; 2) resolving farmersā€™ conflicts and coordination in advance are the key to success; 3) while transferring all facility management to the farmer irrigation association known as the Land Improvement District (LID), the government must constantly supervise and support the LID; 4) the experiences of Japan are relevant to countries that have small-scale farming systems; and 5) there is a rapid shift underway in the primary actors of Japanese agriculture in rural villages, from many small-scale farmers to a limited number of large-scale farmers. This transformation may require reshaping the Japanese model to adapt to new circumstances

    Design and validation of an MPC controller for CMG-based testbed

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    In the last years, Control Moment Gyros (CMGs) are widely used for high-speed attitude control, since they are able to generate larger torque compared to ā€œclassicalā€ actuation systems, such as Reaction Wheels . This paper describes the attitude control problem of a spacecraft, using a Model Predictive Control method. The features of the considered linear MPC are: (i) a virtual reference, to guarantee input constraints satisfaction, and (ii) an integrator state as a servo compensator, to reduce the steady-state error. Moreover, the real-time implementability is investigated using an experimental testbed with four CMGs in pyramidal configuration, where the capability of attitude control and the optimization solver for embedded systems are focused on. The effectiveness and the performance of the control system are shown in both simulations and experiments

    Antigen-independent Induction of Histamine Synthesis by Immunoglobulin E in Mouse Bone Marrowā€“derived Mast Cells

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    Immunoglobulin (Ig)E-mediated activation of mast cells has long been thought to occur only when FcĪµRI receptor-bound IgE is cross-linked via multivalent antigens. However, recent studies have raised the possibility that mast cells may be activated by the binding of IgE to the FcĪµRI receptor in the absence of antigen. Here we demonstrate that IgE binding without antigen induces the expression of histidine decarboxylase (HDC) in mouse interleukin (IL)-3ā€“dependent bone marrowā€“derived mast cells (BMMCs). The induction of HDC by the binding of IgE was found to require an influx of extracellular calcium ions, which was attenuated by pretreatment with U73122, a phospholipase C inhibitor. Furthermore, the increase in HDC activity upon sensitization with IgE was completely suppressed by pretreatment of BMMCs with protein kinase C inhibitors, such as H7, staurosporine, and Gƶ6976. In addition, immediate activation of the tyrosine kinase Lyn was not detectable upon treatment with IgE. These results suggest that the binding of IgE to its receptor in the absence of antigen results in de novo synthesis of HDC in BMMCs through a signaling pathway distinct to that operating during antigen-stimulated FcĪµRI activation

    Clinical application of the Personal Dialysis Capacity (PDC) test: Serial analysis of peritoneal function in CAPD patients

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    Clinical application of the Personal Dialysis Capacity (PDC) test: Serial analysis of peritoneal function in CAPD patients.BackgroundPeritoneal damage has been reported since the beginning of CAPD therapy.MethodsTo clarify the change of peritoneal function in CAPD patients, we used the Personal Dialysis Capacity (PDC) test in 22 patients with 49 serial studies and 14 patients with single studies. The data were expressed at the condition of 2.5% (2.27g/dl of glucose), four times at 2,000 ml/day.ResultsIn the mass analysis, the urea generation rate, creatinine generation rate, PNA/PCR, and water removal via the peritoneum (PD) were kept at the same level for almost eight years, and then gradually decreased. Urine volume and residual renal creatinine clearance (CCr) became zero at six years. On the other hand, PD CCr increased gradually with the time course of CAPD, and therefore the total CCr remained at the level of 6.0ml/min even after six years. Weekly urea KT/V decreased gradually from almost 2.800 to 2.000. The protein loss remained approximately 7.0g/day for the initial five years, then became 6.0g/day, except in five patients who showed levels above 10.0g/day on the first test of PDC. Weekly urea KT/V was correlated with residual renal CCr (P < 0.005), and significantly correlated with total CCr (weekly urea KT/V = -0.2798 + 0.3720 Ɨ total CCr; r = 0.915, P < 0.001). In the serial analysis, when the first and the last tests were compared, the urea generation rate increased significantly (mean Ā± sd, 2.800 Ā± 3.204 vs. 3.882 Ā± 3.382; P < 0.0001); however, water removal via PD (1364 Ā± 887 vs. 813 Ā± 609; P = 0.021), total ultrafiltration (1762 Ā± 841 vs. 1124 Ā± 843; P = 0.042), and weekly urea KT/V (2.285 Ā± 0.486 vs. 2.112 Ā± 0.512; P = 0.026) decreased significantly. The delta water removal via PD/duration became negative (-10.03 Ā± 6.59 ml/week) in all 7 patients after more than four years, however, it was positive (+14.40 Ā± 7.84 ml/week) in 6 of 10 patients after less than one year.ConclusionThese results suggest that water removal via PD increases within one year, then decreases after four years. The PDC test is useful to evaluate the change of peritoneal function in mass and serial analyses
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