Fundamental studies for the application of quench protection systems based on an active power method for cryocooled LTS coils

When the quenching occurs in a superconducting coil, excessive joule heating in normal area may damage the coil. It is necessary to detect quenching in the coil as soon as possible and discharge the magnetic energy stored in the coil. Therefore, we propose a superconducting coil protection system based on an active power method. The system is highly resistant to the noise and does not require cancel voltage taps, so it is useful for both AC and DC coils. We have presented the effectiveness of the system using some test coils cooled in LN₂ or LHe. However, we have not discussed the effectiveness of the proposed system for helium-free cryocooled magnets, in which a larger temperature rise occurs after quenching than in liquid-cooled magnets. In this paper, we verify the effectiveness and practicality of the proposed system through coil protection tests for a cryocooled Nb₃Al LTS coil.     

Voltage Clamp Processor System

A new method of voltage clamping of biological membranes is developed. Usually, series resistance (Rs) is inevitably introduced to the membrane and Rs makes it difficult to control the membrane voltage. The purpose of this study is to compensate undesirable effects of Rs, and to develop an improved voltage clamp system.     

Selection of an optimized method for pitting processes with sustainability as an important factor

Recent engineering products must meet the demand for downsizing and sophistication. Environmentally benign manufacturing has also become a key technology for sustainable development. Striking a balance between product quality and environmental impact in manufacturing processes has become an important issue in the design of eco-friendly products. However, despite this increasing demand from the industry, there is dearth of research on the environmental impact of processing as compared to studies on conventional manufacturing factors such as cost and time. We have tried to clarify the relationship between quality and environmental impact directly from experimental data. The pitting process that we chose as our experimental process is one of the most general and important processes in the industry. In this paper, we discuss a basic concept for selecting optimal processing methods and conditions for the pitting process from the aspect of employing an environmentally benign process. By applying our study to the industry, engineers can easily conduct processes that are not only high in quality but also low in environmental impact.     

Study for pulse stress NBTI characteristics degradation stress

NBTI characteristic degradation of MOSFET is still one of important reliability physics in semiconductor device. Although it is well recognized that its degradation is recovered immediately after releasing DC test stress, it is also fact that the voltage which is applied to the gate electrode in most semiconductor device is an intermittent stress like pulse, not consecutive DC stress as NBTI test. Accurate NBTI lifetime prediction method under this pulse stress condition can afford an actual reliable lifetime. In this work, we considered the characteristic recovery phenomenon in pulse NBTI stress with MOSFET of TOSHIBA 40 nm and 90 nm CMOS process technology and examined a more realistic life prediction method.     

Bilberry and its main constituents have neuroprotective effects against retinal neuronal damage in vitro and in vivo

Our aim was to determine whether a Vaccinium myrtillus (bilberry) anthocyanoside (VMA) and/or its main anthocyanidin constituents (cyanidin, delphinidin, and malvidin) can protect retinal ganglion cells (RGCs) against retinal damage in vitro and in vivo. In RGC cultures (RGC‐5, a rat ganglion cell‐line transformed using E1A virus) in vitro, cell damage and radical activation were induced by 3‐(4‐morpholinyl) sydnonimine hydrochloride (SIN‐1, a peroxynitrite donor). Cell viability was measured using a water‐soluble tetrazolium salt assay. Intracellular radical activation within RGC‐5 cells was evaluated using 5‐(and‐6)‐chloromethyl‐2,7‐dichlorodihydrofluorescein diacetate acetyl ester (CM‐H₂DCFDA). Lipid peroxidation was assessed using the supernatant fraction of mouse forebrain homogenates. In mice in vivo, we evaluated the effects of VMA on N‐methyl‐D ‐aspartic acid (NMDA)‐induced retinal damage using hematoxylin‐eosin and terminal deoxynucleotidyl transferase‐mediated dUTP nick‐end labeling (TUNEL) stainings. VMA and all three anthocyanidins (i) significantly inhibited SIN‐1‐induced neurotoxicity and radical activation in RGC‐5, (ii) concentration‐dependently inhibited lipid peroxidation in mouse forebrain homogenates. Intravitreously injected VMA significantly inhibited the NMDA‐induced morphological retinal damage and increase in TUNEL‐positive cells in the ganglion cell layer. Thus, VMA and its anthocyanidins have neuroprotective effects (exerted at least in part via an anti‐oxidation mechanism) in these in vitro and in vivo models of retinal diseases.     

Improving the Palatability of Salt-Reduced Food Using Dried Bonito Stock

ABSTRACT:  The characteristic flavors, with the exception of umami, of dried bonito stock not only enhanced saltiness but also improved palatability, namely the acceptability, of salt-reduced foods. However, the respective effects of odorants and tastants of dried bonito stock on palatability have yet to be fully explained. Thus, the effect of dried bonito stock aroma on saltiness enhancement and palatability improvement in salt-reduced food was evaluated by sensory assessment. Probit analysis indicated that aromas of the stocks,  arabushi  and  karebushi , did not affect the intensity of saltiness. However, the test sample with aromas of dried bonito stocks was significantly more palatable than the reference sample. The effects of the taste of dried bonito stock were also evaluated. Probit analysis indicated that enhanced saltiness was not observed in the MSG solution but was observed with the dried bonito stocks, when controlled for aroma. These results suggest that saltiness enhancement by dried bonito stock was caused by the characteristic taste (excluding umami) of dried bonito stock, while its characteristic aroma and umami were involved in preventing the loss of palatability of a low-salt diet. Moreover, it was found that using a combination of  karebushi  and dried kelp, as material for making stock, could contribute effectively to the preparation of palatable salt-reduced foods in Japan. Invention of new seasonings for improving the palatability of salt-reduced foods could exploit these findings.     

Reliability-based structural optimization of frame structures for multiple failure criteria using topology optimization techniques

Topology optimization methods using discrete elements such as frame elements can provide useful insights into the underlying mechanics principles of products; however, the majority of such optimizations are performed under deterministic conditions. To avoid performance reductions due to later-stage environmental changes, variations of several design parameters are considered during the topology optimization. This paper concerns a reliability-based topology optimization method for frame structures that considers uncertainties in applied loads and nonstructural mass at the early conceptual design stage. The effects that multiple criteria, namely, stiffness and eigenfrequency, have upon system reliability are evaluated by regarding them as a series system, where mode reliabilities can be evaluated using first-order reliability methods. Through numerical calculations, reliability-based topology designs of typical two- or three-dimensional frames are obtained. The importance of considering uncertainties is then demonstrated by comparing the results obtained by the proposed method with deterministic optimal designs.     

Joint angle control by FES using a feedback error learning controller.

The feedback error learning (FEL) scheme was studied for a functional electrical stimulation (FES) controller. This FEL controller was a hybrid regulator with a feedforward and a feedback controller. The feedforward controller learned the inverse dynamics of a controlled object from feedback controller outputs while control. A four-layered neural network and the proportional-integral-derivative (PID) controller were used for each controller. The palmar/dorsi-flexion angle of the wrist was controlled in both computer simulation and FES experiments. Some controller parameters, such as the learning speed coefficient and the number of neurons, were determined in simulation using an artificial forward model of the wrist. The forward model was prepared by using a neural network that can imitate responses of subject's wrist to electrical stimulation. Then, six able-bodied subjects' wrist was controlled with the FEL controller by delivering stimuli to one antagonistic muscle pair. Results showed that the FEL controller functioned as expected and performed better than the conventional PID controller adjusted by the Chien, Hrones and Reswick method for a fast movement with the cycle period of 2 s, resulting in decrease of the average tracking error and shortened delay in the response. Furthermore, learning iteration was shortened if the feedforward controller had been trained in advance with the artificial forward model.     

Energy losses at three-way circular drop manholes under surcharged conditions

Energy loss at manholes is of importance in the design of storm sewer networks and in flood-analysis. Some researchers have already investigated the energy loss at three-way manholes under surcharged conditions. However, formulation to calculate the energy loss at manholes, including all variables of structural elements of the pipes and of the manhole has not yet been accomplished. Therefore, more study to formulate the energy loss at three-way drop manholes is needed. In this study, the ratio of the diameter between inflow pipes and an outflow pipe, the ratio of flow rates between those pipes, water depth in a manhole and the drop gaps between those pipes are considered and the energy loss at three-way circular drop manholes is examined. Finally, a modified formula, more accurate than that in the U.S. Federal Highway Administration's 2001 Urban Drainage Design Manual is proposed. The proposed formula takes the influence of the ratio of the diameter between inflow pipes and outflow pipe and drop gaps between those pipes into consideration. The calculated energy loss coefficients in both straight-through and lateral pipes successfully reproduce the measured values.     

Albumin microvascular leakage in brains with diabetes mellitus

Their aim was to examine whether microvascular leakage of endogenous albumin, a representative marker for blood–brain barrier (BBB) damage, was induced in the periventricular area of diabetic db/db mice because periventricular white matter hyperintensity formation in magnetic resonance images was accelerating in elderly patients with diabetes mellitus. Using light and electron microscopes, and semi‐quantitative analysis techniques, immunoreactivity of endogenous albumin, indicating vascular permeability, was examined in the periventricular area and spinal cord of db/db mice and db/+m control mice. Greater immunoreactivity of albumin was observed in the vessel wall of the periventricular area of db/db mice than in controls. Additionally, weak immunoreactivity was observed in the spinal cord of both db/db mice and controls. The number of gold particles, indicating immunoreactivity of albumin, in the perivascular area of db/db mice was significantly higher than that of control mice, but there was no significant difference in the number of particles in the spinal cord between db/db mice and controls. These findings suggest that albumin microvascular leakage, or BBB breakdown, is induced in the periventricular area of diabetic mice. Microsc. Res. Tech. 79:833–837, 2016. © 2016 Wiley Periodicals, Inc.