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A 5-year-old male toy poodle was referred for corrective surgery of an atrial septal defect. A sinus venosus-type atrial septal defect (ASD) with partial anomalous venous connection, suspected pulmonary hypertension, and pulmonary edema was confirmed by radiography, echocardiography, and cardiac computed tomography. Thoracic radiographs showed right heart enlargement. Echocardiography revealed right atrial and ventricular dilatation with mild flattening of the interventricular septum. Left-to-right shunt flow through the ASD was observed on color Doppler examination. Surgical correction of the sinus venosus ASD with a partial anomalous pulmonary venous connection was performed under cardiopulmonary bypass. A follow-up evaluation at 1 year after surgery showed resolution of the right-sided volume overload and no evidence of recurrence of ASD. Complications were not observed. Our findings indicate that surgical correction under cardiopulmonary bypass is a valid treatment option for an ASD with a partial anomalous pulmonary venous connection.

Introduction Information about real-time three-dimensional (3D) transesophageal echocardiography (TEE) for the evaluation of canine mitral valve morphology is lacking in veterinary medicine. Objectives To evaluate the feasibility of 3D TEE for the evaluation of canine mitral valves and whether there was a difference in mitral valve morphology between American College of Veterinary Internal Medicine (ACVIM) stages. Animals Thirty-one dogs were evaluated, including nine dogs classified as ACVIM stage B2, 15 as stage C, and seven as stage D. Materials and methods Three-dimensional TEE was performed after anesthetic induction for mitral valve surgery, and the 3D geometry of the mitral valve apparatus was measured. Results The intraclass correlation coefficient was good in both inter- and intraobserver analyses of the 3D measurements of mitral valve annulus geometry and excellent in both inter- and intraobserver analyses in the 3D measurements of mitral valve annular and leaflet sizes. Annulus height to commissural width ratio of stage D dogs showed significantly lower values than B2 dogs (B2: 14.2% [9.1–20.5%]; C: 10.6% [6.5–24.1%]; D: 9.5% [4.7–13.8%]). The aortic–mitral angle of stages C and D were significantly flatter than stage B2 (B2: 122.32 ± 9.39; C: 133.66 ± 8.43; D: 140.70 ± 10.70). Conclusions Real-time 3D echocardiography using TEE is a feasible method to evaluate the morphology of the mitral valve in dogs. The saddle shape of the mitral annulus and aortic–mitral angle were flatter in stage D. Further studies are required to understand the pathology of mitral valve disease in dogs.

A method of suppressing vibration in lateral directions is investigated based on varying stiffness strategy. A vertically controlled magnetic suspension system is often subjected to vibration in lightly damped lateral directions. In this paper, a novel approach is proposed to detect the lateral displacement of such magnetic suspension system, and how this displacement can be used to reduce vibration by varying stiffness control is presented. The principle of edge effect is applied to detect the lateral displacement in a magnetic suspension system operated in differential mode. A switching stiffness control and a modified control strategies are used to vary the stiffness of the system in order to reduce lateral vibration. Several experiments are carried out to validate the efficiency of the proposed method.

A frequency-following servocompensator is applied to a rotary gyro with flexures gimbal to eliminate the oscillating components from the estimated signals. In the targeted gyro, a synchronous motor is fixed to a rectangular holder and a disk-type rotor is driven by the motor to generate gyroscopic couplings. The coupled two rotational motions of the holder are controlled by four electromagnets on the stator; the angular velocities are estimated from the control currents to regulate the relative displacement of the holder to the stator. The other four-degree-of-freedom motions of the holder are constrained by the flexures gimbal. Such suspension using flexures makes the system less damped so that high accuracy is expected to this gyro. However, one of the problems is that an oscillating component caused by rotor unbalance appears in the estimated signal because the estimation is based on the control input. To solve this problem, the frequency-tracking servocompensator is applied to eliminate the oscillating component. The virtually perfect elimination of the component from the estimated signal was achieved.

The controllability and observability of parallel magnetic suspension systems are investigated analytically. A parallel magnetic suspension system has multiple floators and electromagnets driven by a single amplifier. In this paper, the multiplicity is set to an arbitrary counting number n. Parallel systems are classified into four types based on the output of the power amplifier and the connection of the coils. This paper treats three of them: current-controlled with series-connected coils; voltage-controlled with series-connected coils; and voltage-controlled with parallel-connected coils. The conditions of controllability and observability of each system are clarified. The feasibility of parallel magnetic suspension is demonstrated by simulations and experiments.

Introduction In recent years, novel MOSFET characteristics dominated by a single dopant-atom were reported by several groups [1-4], where carrier transport mechanism is tunneling through individual dopant atoms. In this background, we have proposed and demonstrated a variety of dopant-atom devices, i.e., dopant-atom (DA) transistors [4], DA memories [5], DA turnstiles [6-8] and DA photonic devices [9-11]. In those devices, only one or a few dopants are intentionally used and one dopant works as a quantum well for electron (or hole) tunneling transport. Here, we present a brief overview of such devices from experimental and theoretical point of view. P-donor in nano-Si When we focus on a phosphorous (P) donor atom, it is known that the ionization energy, or the binding energy, with respect to the Si conduction band minimum, is ~45 meV. Therefore, single-electron tunneling P-atom devices can operate only at low temperatures, below ~20 K, since at high temperatures electrons are thermally excited and tunneling transport mechanism does not work. However, when a dopant is embedded in sufficiently small Si structures, its ionization energy is enhanced due to dielectric and quantum size confinement effects [12], leading to high-temperature operation. Recently, we have demonstrated operation of donor-atom SOI-MOSFETs at around 100 K in specifically-designed nano-stub-channels [13]. A good correlation is found between the operation temperature and binding energy (E a), with the highest SET-operation temperature being achieved for a P donor with E a≅ 100 meV [13]. A few coupling donors So far, in most investigated dopant-atom devices, the dopants were introduced in random positions. Only a few works addressed directly the control of dopants, either in number, using single ion implantation [14], or in position, with atomic manipulation using scanning tunnelling microscope tips [15]. Most recently, we have challenged a more practical and simpler doping technique using nanoscale doping masks [16]. The channel of SOI-MOSFET was selectively doped within an area of ~30 nm in width by the conventional diffusion process. Even in such a classical doping process, the number of dopants in the doped area may be controlled to around 5. I-V characteristics measured for these selectively-doped FETs are consistent with the model [16]. Nano-pn junctions Individuality of dopants appears not only in nano-FETs, but also in nano-pn diodes. In fact, we have reported dopant-induced random telegraph signals (RTS) in nanoscale pn diodes [17], and attributed the RTS to charging and discharging of a single dopant near the pn junction. Observation of dopant potential In research of dopant-atom devices, it is extremely important to establish an observation tool to monitor dopants’ positions and their individual potentials. For this purpose, we have developed low-temperature Kelvin probe force microscopy (LT-KFM) which allows measurements of devices under regular operation. Using this technique, we succeeded in detection of potential profiles due to individual dopants and potential changes due to single-electron injection effects [18-21]. References [1] H. Sellier et al: Phys. Rev. Lett. Vol. 97 (2006), p. 206805. [2] G.P. Lansbergen et al: Nature Phys. Vol. 4 (2008), p. 656. [3] Y. Ono, et al: Appl. Phys. Lett.Vol. 90 (2007), p. 102106. [4] M. Tabe et al: Phys. Rev. Lett. Vol. 105 (2010), p. 016803. [5] E. Hamid et al: Appl. Phys. Lett. Vol. 97 (2010), p. 262101. [6] D. Moraru et al: Phys. Rev. B Vol. 76 (2007), p. 075332. [7] D. Moraru et al: Appl. Phys. Express Vol. 2 (2009), p. 071201. [8] K. Yokoi et al: J. Appl. Phys. Vol. 108 (2010), p. 053710. [9] M. Tabe et al: Phys. Stat. Sol. A Vol. 208 (2011), p. 646. [10] A. Udhiarto et al: Appl. Phys. Lett. Vol. 99 (2011), p. 113108. [11] A. Udhiarto et al: Appl. Phys. Express Vol. 5 (2012), p. 112201. [12] M. Diarra et al: Phys. Rev. B Vol. 75 (2007), p. 045301. [13] E. Hamid et al: Phys. Rev. B Vol. 87 (2013), p. 085420. [14] E. Prati et al: Nature Nanotechnol. Vol. 7 (2012), p. 443. [15] M. Fuechsle et al: Nature Nanotechnol. Vol. 7 (2012), p.242. [16] D. Moraru et al: Sci. Rep. Vol. 4 (2014), p. 6219. [17] S. Purwiyanti et al: Appl. Phys. Lett. Vol. 103 (2013), p. 243102. [18] M. Ligowski et al: Appl. Phys. Lett. Vol. 93 (2008), p. 142101. [19] M. Anwar et al: Appl. Phys. Lett. Vol. 99 (2011), p. 213101. [20] M. Anwar et al: Jpn. J. Appl. Phys. Vol. 50 (2011),p. 08LB10. [21] R. Nowak et al: Appl. Phys. Lett. Vol. 102 (2013), p. 083109.

Further development of dopant-atom-based transistors requires investigation of the effects of discrete dopant distribution on device operation. Hence, it is important to monitor dopants’ arrangement inside transistor channels. We used Kelvin Probe Force Microscope (KPFM) to measure surface potential profiles of field-effect transistor (FET) channels doped with different concentrations of phosphorus atoms. We observed three basic configurations of dopants: solitary donors, “clusters” of a few coupled donors, and “clusters” of many donors. Our systematic observation provides information about the formation of quantum dots consisting of a single donor or a number of coupled donors.

Two vibration control techniques, negative stiffness and displacement cancellation, are characterized and employed to achieve active vibration isolation. A horizontal vibration isolation system is developed and then used to investigate each of these techniques theoretically and experimentally. The respective responses of the developed system are measured separately while closed-loop poles of the system are kept unchanged; these measured responses are compared. The developed system is based on a series combination of two isolators and consists of two moving tables; one of the moving tables is mounted on the series-connected isolators and the other is placed between the isolators. Using the negative stiffness technique, the isolators are controlled so that one of them has a negative stiffness and the other has a positive stiffness of equal absolute magnitude; using the displacement cancellation technique, one isolator is set to cancel displacement while the other behaves as a positive-stiffness isolator. The active negative, positive, and displacement cancellation isolators are created using voice-coil motors guided by a negative stiffness controller, proportional derivative controller and integral-proportional derivative controller, respectively.

Objectives To evaluate the functionality of an autologous heart valve with stent (Stent-biovalve or SBV) after implantation in the pulmonic valve position in beagle dogs. Animals Five beagle dogs. Methods A mold with an aperture of a tri-leaflet structure was constructed from a pair of concave and convex rods to which a nitinol (NiTi) stent was mounted. This mold was embedded in a dorsal subcutaneous pouch in beagle dogs for 4 weeks. At the time of the removal, the surfaces of the molds were completely covered with connective tissues, tri-leaflet valves were formed and the NiTi stent was tightly connected to the structure. Results The mean burst strength of the SBV leaflet was 2710 mmHg (range 2280–3116 mmHg), which was approximately equal to that of the native pulmonic valve leaflet. After implantation in the pulmonary position, the SBV showed good functionality as a pulmonic valve. At 84 days after implantation, the SBV was replaced with autologous fibroblasts and collagenous tissues, and showed organization similar to that of native heart valves. Conclusion Stent-Biovalves achieved good valvular function with laminar flow in the pulmonic valve position of beagle dogs.

A solar-powered magnetic suspension carrier is fabricated which achieves noncontact power supply to the carrier. There are two conventional methods of supplying power to a carrier. One is through wires or contacts such as pantograph and the other is an on-board battery in the carrier. However, the contactless property is lost in the former while stations for charging the on-board battery are necessary in the latter. These problems are overcome by the proposed carrier system using solar magnetic suspension that can achieve continuous levitation. It is assumed for the system to operate indoors like inside a factory building. The generation of power by solar cells is low so that the magnetic suspension needs power saving. A zero power control system is applied to the suspension of the floator. In addition, low-power peripheral devices are also fabricated. The developed carrier system achieved a 24-hour levitation without external power supply in a bright environment.

A mass-spring system with a dynamic vibration absorber has a fixed point in its frequency response curves. A method of measuring mass using this property was proposed. It has an advantage that mass is estimated independently of the damping in the absorber. The developed system was characterized by using a phase-looked loop to achieve the tuning condition. However, because the actuator producing the harmonic force was mounted on the base, the reaction force was transmitted to the surrounding structure. It may cause a severe vibration of the surrounding structure. Therefore, it is necessary to prevent transmission of force to the surrounding structure in measuring. In this paper, a new type of mass measurement system is proposed which uses an inertial-mass vibrator to reduce the transmitted vibration. The tuning conditions are derived for both systems with a damped absorber and with an undamped absorber. The principles of measurement are described based on a mathematical model. An experimental apparatus is designed and fabricated. The efficacy of the measurement system with an inertial mass-type vibrator is studied both analytically and experimentally.

The controllability of gyroscopic systems is studied analytically. Two rotational motions of the rotor interact each other due to gyroscopic effects when the rotor is rotating. They are usually controlled with two control inputs in totally active magnetic bearing systems. Meanwhile, two degrees of freedom are controlled with a single control input in double parallel magnetic suspension systems. Such an approach is applied to gyroscopic systems in this article. Two rotational motions are controlled with a single control input. The conditions for gyroscopic systems to be controllable are clarified.

The use of stent grafts for endovascular aortic repair has become an important treatment option for aortic aneurysms requiring surgery. This treatment has achieved excellent outcomes; however, problems like type 1 endoleaks and stent graft migration remain. Bio stent grafts (BSGs), which are self-expanding stents covered with connective tissue, were previously developed using "in-body tissue architecture" technology. We assessed their early adaptation to the aorta after transcatheter implantation in a beagle model. BSGs were prepared by subcutaneous embedding of acryl rods mounted with self-expanding nitinol stents in three beagles for 4 weeks (n = 3/dog). The BSGs were implanted as allografts into infrarenal abdominal aortas via the femoral artery of three other beagles. After 1 month of implantation, aortography revealed no stenosis or aneurysmal changes. The luminal surface of the BSGs was completely covered with neointimal tissue, including endothelialization, without any thrombus formation. The cover tissue could fuse the luminal surface of the native aorta with tight conjunctions even at both ends of the stents, resulting in complete impregnation of the strut into the reconstructed vascular wall, which is expected to prevent endoleaks and migration in clinical applications.

As electronic device dimensions are continuously reduced, applied bias conditions significantly change and the transport mechanisms must be reconsidered. Tunneling devices are promising for scaled-down electronics because of expected high-speed operation and relatively low bias. In this work, we investigated the tunneling features in silicon-on-insulator lateral nanowire pn junction and pin junction devices. By controlling the substrate voltage, tunneling features can be observed in the electrical characteristics. We found that the minimum substrate voltage required for tunneling to occur in pn junctions is higher as compared with pin junctions. The main cause of these effects relies in the difference between the doping profiles, since the pn junctions contain a co-doped region, while the pin junctions contain an i-layer.

Nanoscale pn junctions have been investigated by Kelvin probe force microscopy and several particular features were found. Within the depletion region, a localized noise area is observed, induced by temporal fluctuations of dopant states. Electronic potential landscape is significantly affected by dopants with ground-state energies deeper than in bulk. Finally, the effects of light illumination were studied and it was found that the depletion region shifts its position as a function of light intensity. This is ascribed to charge redistribution within the pn junction as a result of photovoltaic effect and due to the impact of deepened-level dopants.

A vibration isolation module with zero-power magnetic suspension is developed to retrofit a passive vibration isolation system to improve the performance against direct disturbance. In the module, the zero-power magnetic suspension mechanism is connected in series with a normal spring through a middle mass. This structure can generate zero compliance to direct disturbance while the transmitted vibration is still reduced. Such zero- compliance module was actually designed and fabricated. The characteristics of the fabricated module were studied experimentally. A passive vibration isolation system using air springs were retrofitted with four modules. It was demonstrated that the performance against direct disturbance was improved significantly.

The rubber hand illusion (RHI) is a bodily illusion that a fake rubber hand is felt as if it was one's own hand when both the hands are synchronously stimulated. Also, it is well-known that people can experience the RHI when the movements of the visible fake and invisible real hands are synchronized. However, underlying mechanism of the RHI and relationship between action and body ownership are still open questions. Based on the RHI paradigm, the present paper discusses how the agency of a body part affects the sense of body ownership at the other body part. In this study, we examined if a simple up-and-down action of right index finger induces the RHI to left hand which was kept still by using virtual reality and robotics technologies. Our experimental results indicated that the action of the right index finger allowed the embodiment of the virtual hands at both the right and left hands. This implies that only a simple action of a body part increases the sense of body ownership at the other body part.

The aim of this study was to evaluate the efficacy of pimobendan with conventional therapies on survival and reocurrence of pulmonary edema in dogs with congestive heart failure (CHF) caused by myxomatous mitral valve disease (MMVD). Records of 197 client-owned dogs from 14 veterinary hospitals were included in this study. Dogs were administered conventional treatments with or without pimobendan. Sixty-four dogs received a standard dose of pimobendan (0.20-0.48 mg/kg every 12 hr (q12hr)), 49 dogs received a low dose of pimobendan (0.05-0.19 mg/kg q12hr), and 84 dogs received conventional therapy alone. Dogs in the standard-dose and low-dose pimobendan groups had significantly longer median survival times than dogs in the conventional group (334, 277 and 136 days, respectively; P

Silicon tunnel devices are important for low power-consumption and fast-switching electronics. Inter-band tunneling current is, however, limited due to the indirect-bandgap nature of Si, but low-dimensionality of the devices may bring new effects into play. In this work, we analyze two-dimensional lateral Si Esaki diodes and first observe that inter-band tunneling is still largely mediated by phonon assistance. More importantly, however, we find that tunnel current is significantly enhanced by resonances involving dopant-atoms with deeper energy levels in the depletion region. These results experimentally illustrate the impact of atomistic effects in low-dimensional tunnel devices.

Single-electron tunneling in donor-atom transistors has been reported mostly at low temperatures, due to the relatively low tunnel barrier. Higher tunnel barrier, necessary for room-temperature operation, can be expected by coupling closely-placed donors to form a quantum dot (QD). For that purpose, we fabricate a-few-donor QDs in narrow-channel SOI-FETs by a selective-doping technique. In these devices, we observe Coulomb diamonds up to high temperature (T>150 K), while current peaks prominently survive even up to room temperature. The interplay between barrier height and charging energy in promoting room-temperature operation is also discussed.

A positioning device for placing a magnetized component on a ferromagnetic plate without collision has been fabricated. When the magnetized component approaches to the plate, the attractive force between them increases sharply as the gap decreases. It sometimes causes them to collide. To prevent such collision, a force compensation control is applied to cancel such nonlinear disturbance force by the actuator driving the component. In addition, a command revision control is implemented to avoid collision even in the presence of errors in modeling and positioning. The effectiveness of the proposed control schemes is demonstrated experimentally.

In near-field levitation, an object can be levitated vertically upward above vibrating surface of an ultrasonic transducer. In this case, a repulsive force acts on the object. On the other hand, it has been reported that a minute object can be suspended vertically downward under the vibrating surface with a small gap in the air. We call this phenomenon ultrasonic suspension. Under the suspension, an attractive force acts on the object. When an object is suspended, there is restoring force, which pulls the object to the center of the vibrating surface. Our aim is to characterize the actuation forces under the suspension. Simultaneous measurement of vertical and horizontal actuation forces is required. A servo type measuring mechanism was proposed. A 1 DOF mechanism with a cantilever and a voice coil motor (VCM) was fabricated as a prototype. The prototype was calibrated and utilized for measurement of vertical actuation force. The result showed enough accuracy and repeatability. Then, a 2 DOF actuation force measurement mechanism was fabricated. The mechanism was consisted of a base to fix the object and two thin wires to support the base. Position of the base was controlled by three VCMs based on PID control. The ultrasonic suspension actuation forces were characterized successfully.

In this study, the authors focus on active touch by a stylus and reproduction of its sensation. Using the stylus, they can recognize the texture of an object surface through a stylus vibration according to the touch. Introducing a concept “Tele-touch,” users can experience the texture at remote site through the controlled stylus. A tele-touch stylus was proposed to realize the stylus-based tele-touch system. The authors focused the rotational vibration of the stylus by rubbing, thus a gyro sensor was installed in the stylus. At a remote site, a stylus acts as a capturer of vibration. The captured information is transmitted to the user site and utilized for the control of a tactile display to reproduce the sensation. The user can experience the texture at the remote site. This paper describes the tele-touch stylus, transfer functions involved in system control and experimental results.

Objective—To determine whether mitral valve repair (MVR) under cardiopulmonary bypass would be an effective treatment for mitral regurgitation in small-breed dogs. Design—Retrospective case series. Animals—48 small-breed dogs (body weight, 1.88 to 4.65 kg [4.11 to 10.25 lb]; age, 5 to 15 years) with mitral regurgitation that underwent surgery between August 2006 and August 2009. Procedures—Cardiopulmonary bypass was performed with a cardiopulmonary bypass circuit. After induction of cardiac arrest, a mitral annuloplasty was performed, and the chordae tendineae were replaced with expanded polytetrafluoroethylene chordal prostheses. After closure of the left atrium and declamping to restart the heart, the thorax was closed. Results—Preoperatively, cardiac murmur was grade 3 of 6 to 6 of 6, thoracic radiography showed cardiac enlargement (median vertebral heart size, 12.0 vertebrae; range, 9.5 to 14.5 vertebrae), and echocardiography showed severe mitral regurgitation and left atrial enlargement (median left atrium-to-aortic root ratio, 2.6; range, 1.7 to 4.0). 45 of 48 dogs survived to discharge. Three months after surgery, cardiac murmur grade was reduced to 0/6 to 3/6, and the heart shadow was reduced (median vertebral heart size, 11.1 vertebrae, range, 9.2 to 13.0 vertebrae) on thoracic radiographs. Echocardiography confirmed a marked reduction in mitral regurgitation and left atrium-to-aortic root ratio (median, 1.7; range, 1.0 to 3.0). Conclusions and Clinical Relevance—We successfully performed MVR under cardiopulmonary bypass in small-breed dogs, suggesting this may be an effective surgical treatment for dogs with mitral regurgitation. Mitral valve repair with cardiopulmonary bypass can be beneficial for the treatment of mitral regurgitation in small-breed dogs.

Mitral valve repair is one of the treatment options for mitral regurgitation. Expanded polytetrafluoroethylene (ePTFE) is a polymer that has been widely used in cardiovascular surgery. In this case series, we report the autopsy and histological findings in 6 dogs that underwent cardiopulmonary bypass for mitral annuloplasty using ePTFE sheets and chordoplasty using ePTFE sutures. From May 2005 to October 2009, 3 female and 3 male dogs with severe mitral regurgitation underwent mitral valve repair. This case series included 3 Cavalier King Charles spaniels, 2 Maltese, and 1 Shih Tzu. The survival period after surgery was 19–72 (35 ± 19) months. In all the cases, autopsy revealed that the ePTFE sheets and sutures were not damaged and well integrated into the surrounding highly differentiated, connective tissues. Low-power microscopy revealed that in all cases, the tissues surrounding the ePTFE sheet in the mitral valve annulus had almost completely been covered by granulation tissue. No inflammatory infiltrate or thrombogenesis was observed around the ePTFE in any of the cases. There was no evidence of reactive changes in the region surrounding the ePTFE. These results suggest that ePTFE has excellent tissue compatibility and durability and can be effectively used for canine mitral valve repair.

In this paper we present an improved zero-power controlled magnetic suspension system that has the capability to adjust stiffness. The conventional zero-power control system produces constant negative stiffness, and the stiffness solely depends on the capacity of the permanent magnets or the gap–force coefficient of the magnets. This becomes an obstacle to the fields of application of zero-power control where the adjustment of stiffness is necessary, such as developing a vibration isolation system. In this research, the basic zero-power control system is modified such that it can adjust stiffness by adding a minor proportional feedback of displacement to the zero-power controller. Finally, a vibration isolation system is developed by combining a positive stiffness spring in series with a negative stiffness suspension realized by the modified zero-power controller. The proposed control system and the developed vibration isolation system are investigated both analytically and experimentally.

This paper proposes a module-type three-degree-of-freedom vibration isolation system using modified zero-power control. Three vibration isolation modules are connected together using parallel mechanism to control 3-DOF motions. Each module consists of a common base, an individual middle mass and a common isolation table. The base to the middle mass is suspended by positive springs generated by active and passive system, and the middle mass and the isolation table is connected by negative spring realized by active-type modified zero-power control. The developed system could realize zero-compliance to direct disturbances as well as good ground vibration isolation. Furthermore, the isolation table is supported by a weight support mechanism for supporting heavy payloads. In the previous research, a concentrated middle mass with redundant actuators, in the vertical and horizontal directions, were used. Therefore, a vibration isolation system is proposed in this work using modular concept to overcome those drawbacks. Each module is controlled separately by decentralized control technique, and three modules can be used for three-degree-of-freedom of motion control. Therefore, no redundancy of actuator is occurred. Moreover, an improved zero-power controller is presented that can adjust negative stiffness instead of conventional zero-power controller. The results obtained from analytical and experimental studies show that the modular technique is reliable and efficient approach to vibration control, and represents a suitable alternative to the conventional active vibration isolation systems.

Objective: To describe surgical repair of a large atrial septal defect (ASD) in a cat. Study Design: Clinical report. Animal: A 3-year-old, 3.3 kg, intact male Japanese domestic short-haired cat. Methods: A 10.2-mm-diameter ASD detected by echocardiography was surgically corrected because pulmonary vascular resistance-to-systemic vascular resistance ratio (Qp/Qs) was 3.2. Using cardiopulmonary bypass (CPB), open surgical repair was achieved with an expanded polytetrafluoroethylene (e-PTFE) graft. The priming volume of the CPB circuit was minimized by cutting the CPB tubing, and partially replacing the priming fluid with whole cat blood. To prevent hemodilution associated with use of cardioprotective agents, surgery was performed on the beating heart. Results: At 1-year echocardiographic evaluation, the repair was intact, and at 3 years, the cat was alive without need of medication. Conclusions: Large ASD in a cat can be repaired using e-PTFE under CPB.

Transistors have been significantly downsized over the past decades, reaching channel dimensions of around 100 nm. In nanoscale, quantum effects start to play a key role in device operation, allowing the development of applications based on new physics. In silicon nanodevices, for instance, the device downsizing is associated with a reduction of the number of impurities (dopants) incorporated in the channel. Dopants can play an active role in device operation, mediating the electron transport between source and drain. Here, we present a new device concept of a memory based on the interaction between dopants in nanoscale field-effect transistors. As a basis for memory operation, we show experimental results of single-electron charging in individual dopants monitored by a single-electron current flowing through a dopant array.

Low temperature Kelvin Probe Force Microscopy (LT-KFM) can be used to monitor the electronic potential of individual dopants under an electric field. This capability is demonstrated for silicon-on-insulator field-effect-transistors (SOI-FETs) with a phosphorus-doped channel. We show results of the detection of individual dopants in Si by LT-KFM. Furthermore, we also observe single-electron charging in individual dopants located in the Si channel region.

We have demonstrated that Si single-electron SOI-MOSFETs with multidots channel have attractive new functions such as single-photon detection. Multidots formed by nanoscale selective oxidation of thin SOI layer have been used for photon detection. Most recently, we have investigated photon detection capabilities of FETs having phosphorus (P)-doped channel. In such P-doped FETs, each P donor works as a quantum dot for electrons and single-electron transport is achieved by tunnelling through donor potentials. Using such P-doped FETs, single-photon detection has been demonstrated. Furthermore, in order to directly observe the spatial landscape of even a single-dopant potential, we have developed low-temperature-Kelvin probe force microscopy (LT-KFM) and succeeded in detecting a single-dopant potential in the channel region. In this paper, we present results of photon-induced random telegraph signals in crystalline-dot-type and donor-dot-type multidot single-electron SOI-MOSFETs, and direct observation of a single-dopant potential by LT-KFM.

This paper discusses the feasibility of zero-power control in parallel magnetic suspension systems. In parallel magnetic suspension systems, multiple floators are suspend with a single power amplifier. The zero-power control has been used in magnetic suspension systems with permanent magnets providing bias flux. This control realizes the steady states where the attractive force produced by the permanent magnets balances the weight of the suspended object and the electromagnet coil current converges to zero. This paper shows that parallel magnetic suspension systems incorporating zero-power control can assign the poles arbitrary if the original parallel suspension systems are controllable. The feasibility of the zero-power control in a parallel magnetic suspension is demonstrated experimentally.

This paper presents a vibration isolation system using negative stiffness suspension. The vibration isolation system is developed by combining a positive stiffness suspension in series with a negative stiffness suspension. The developed system could realize zero-compliance to direct disturbance, as well as ground vibration isolation. In the previous system, the ground vibration and, the static and low frequency sinusoidal direct disturbances were efficiently suppressed. However, there was a reverse action in case of impulse or step wise disturbance. Therefore, a peak was appeared which was, sometimes, larger than the displacement caused by the step load. This unpleasant response might hamper the objective function of many advanced systems. In this research, a feedforward controller is added in combination with zero-power control to overcome this problem. Some experimental results are presented to verify the proposed control system in a vibration isolation apparatus.

A three-degree-of-freedom (3-DOF) active vibration isolation system using displacement cancellation control technique is developed. The displacement cancellation concept is presented and implemented in this research to obtain zero compliance of vibration isolation table against direct static force as well as to suppress the dynamic disturbances acting on the isolation table. In the displacement cancellation control technique, relative movements of the vibration free table are followed with I-PD control and movements of the middle mass respect to base are controlled with PD control. The corresponding controllers are designed in such way so that actuator can generate opposite force against disturbance to cancel the effect of displacement of the middle mass on the vibration isolation table, which finally leads zero compliance of the isolation table. Voice coil motors (VCMs) are used for getting linear actuating effect and corresponding displacements of the table are detected by eddy-current gap sensors. The experimental results showed that the developed system with displacement cancellation mode control has capability to maintain zero compliance against direct static force in the 3-DOF motions associated with horizontal translations and a vertical rotation. Moreover experiments have been conducted to measure the dynamic responses of the vibration isolation table to direct disturbance.

In series-type multiple magnetic suspension systems, multiple floators are suspended in tandem by one electromagnet. The nearest floator to the electromagnet is directly suspended by the electromagnet. The others are indirectly suspended by the attractive force due to the magnetization of the floators. The controllability and observability of series-type multiple magnetic suspension systems with an arbitrary number of floators are discussed. They are controllable and also observable even when only the displacement of the floator nearest to the electromagnet is detected. A series-type multiple magnetic suspension system was fabricated in order to verify the analyses experimentally. In the fabricated system, magnetic suspension units that are equipped with a sensor and an electromagnet are used instead of normal floators to carry out experiments in various conditions. As the first step to realize the levitation of multiple floators using one electromagnet and one sensor, a basic trial was carried out in the fabricated system.

This paper studies the controllability of parallel magnetic suspension. The most basic magnetic suspension system consists of a suspended object (floator), an electromagnet and a power amplifier. In parallel magnetic suspension, multiple floators and electromagnets are controlled with a single power amplifier. The concept and the fundamental properties of parallel magnetic suspension systems have been already presented. They are classified according to the output of power amplifier and the connection of coils. However, the polarity of electromagnet has not been treated yet. In this work, the effect of the polarity is taken into consideration. It is shown that the controllability is independent of the polarity.

A review of mass measurement devices developed by the author is presented. According to the measurement principles, the treated devices are classified into two types. The first type uses a dynamic vibration absorber as a device for both mass measurement and vibration control. The main advantage is no vibration transmitted into the surrounding structures during measurement. The second type uses relay feedback. The advantages are simpler mechanism and robustness against disturbances. In this article, the principles of measurement of each type are presented.