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We have been developing the scale removal system utilizing superconducting magnet that can remove iron scale from boiler feed-water in a thermal power plant. The scale removal prevents the plants from the reduction in power generation efficiency. Iron oxide scale consists of the ferromagnetic and the paramagnetic particles, and the optimal separation conditions largely differ depending on the magnetic properties of the particles. So, single separation condition may cause the filter blockage by over capture or inadequate capture. We proposed the two-stage magnetic separation according to the magnetic properties of the aggregates, where the ferromagnetic particles are captured in the 1st stage in low magnetic field and field gradient, and then the paramagnetic ones are captured in the 2nd stage in high magnetic field and field gradient. It was shown that two-stage magnetic separation system for the mixture of ferromagnetic and paramagnetic particles is possible by utilizing one superconducting solenoidal magnet.

In the boiler feed-water system of thermal power plants, iron oxide scale is generated due to the corrosion of piping, which decreases the effectiveness of the heat exchanger in the boiler and contributes to reduced power generation efficiency. Scale removal can prevent this phenomenon, which consequently results in decreased carbon dioxide emission. In a previous study, an iron scale removal system was developed using superconducting magnets, and high-gradient magnetic separation (HGMS) experiments were conducted using the height difference between the inflow and outflow tanks. As a result, particles were intensively captured by the filters at the inflow side. We succeeded in eliminating this capture by properly controlling the applied magnetic field. However, because the suspension also flowed due to the height difference in this experiment, the problems of partial blockage of the filter and the resulting decrease in the flow rate were not resolved even under the controlled magnetic field. In this study, HGMS experiments were conducted under a constant flow rate with a large pump in a large-scale system having a filter diameter of 300 mm to simulate a boiler feed-water system or chemical cleaning line. Furthermore, we investigated the feasibility of the large-scale HGMS system and elucidated the scale-up effect on the amount captured and the spatial distribution of the captured particles on the filters. Based on these results, a plant-scale HGMS system (800 mm filter diameter) was designed.

We have been developing a scale removal system utilizing a superconducting magnet that can remove the iron oxide scale from the boiler feed-water in the thermal power plants. Scale removal can prevent a decrease in the power generation efficiency and contribute to reduce the carbon dioxide emissions. In our previous study, we conducted the large-scale experiments for practical use, but model particles were intensively captured by the inflow side filter. In this paper, we succeeded to homogenize the distribution of captured particles in the filter stacks by controlling the applied magnetic field strength. In addition, magnetic field strength dependency of filter blockage was examined in the lab-scale experiments to clarify a detailed mechanism of blockage.

In Eqs. (1-2), t is the pointing time, A is the amplitude (distance) to the target, W is the target size and a, b are constants that depend on experiment conditions. ID is larger as A is larger and/or W is smaller. Values of a and b in Eq. (1) are determined by sampling (A, W, t) data and applying the linear regression analysis to the data. Eq. (2) shows that ID values are the same for (A, W) and (nA, nW) where n > 0. This research is motivated by recent smart phones that employ touch UIs. Compared with other touch screen devices such as tablet PCs, mobile phones have smaller screens so that widgets on mobile phone screens are likely to be smaller. Widgets can be designed for devices with various screen sizes so that theoretical ID values in Eq. (2) are consistent among the devices: larger/smaller sizes & distances for larger/smaller screens. If ID in Eq. (2) is an appropriate index of actual pointing difficulty independently of screen sizes, users’ pointing performances on the same device are consistent among widget designs (A, W) and (nA, nW): note that a, b in Eq. (1) are constant (independent to ID) so that a, b must be the same for two data sets sampled with the two widget designs (A, W) and (nA, nW). The aim of this research is to investigate whether the above is true: appropriateness of the ID formulation in Eq. (2) is evaluated from the viewpoint of dependency on screen sizes, by experiments with participants. Limitations of Fitts’ law have been researched and extensions have been proposed. For example, an extension for 2D pointing tasks was proposed (MacKenzie & Buxton, 1992). Our research aims at investigating possible limitations on screen sizes. A related research was previously reported (Oehl et al., 2007). They investigated how display size influenced pointing performances on a touch UI and reported that in large displays a fast and comparably accurate execution was chosen in contrast to a very inaccurate and timeconsuming style in small displays. In their research the size of small screen was 6.5”, and only a large screen touch UI device was utilized for user experiments: screen sizes were

To improve thermal power plant efficiency, we proposed a water treatment system with a high gradient magnetic separation (HGMS) system using a superconducting magnet, which is applicable in high-temperature and high-pressure conditions. This is a method to remove the scale from feed-water utilizing magnetic force. One of the issues for practical use of the system is how to extend the continuous operation period. In this paper, we succeeded in solving the problem by eliminating the deviation of captured scale quantity by each filter. In fact, in the HGMS experiment using the solenoidal superconducting magnet, it was shown that a decrease in separation rate and an increase in pressure loss were prevented, and the total quantity of captured scale increased by proper filter design. The design method of the magnetic filter was proposed and will be suitable for long-term continuous scale removal in the feed-water system of the thermal power plant.

We are developing a superconducting magnetic separation system to remove scale or iron oxide from boiler feedwater in thermal power plants. The reduction of scale improves energy conversion efficiency of thermal power plants and reduces discharged CO 2 . We have studied suitable installation locations and operation conditions and examined the separation ability of the system located near the boiler where the water is at high temperatures and pressures. We have concluded that the magnetic separation system is effective to remove scale of boiler feedwater and that the use of a superconducting magnet is essential for the system.

A Superconducting High Gradient Magnetic Separation (HGMS) system is proposed for treatment of feed-water in thermal power plant [1]. This is a method to remove the iron scale from feed-water utilizing magnetic force. One of the issues for practical use of HGMS system is to extend continuous operation period. In this study, we designed the magnetic filters by particle trajectory simulation and HGMS experiments in order to solve this problem. As a result, the quantity of magnetite captured by each filter was equalized and filter blockage was prevented. A design method of the magnetic filter was proposed which is suitable for the long-term continuous scale removal in the feed-water system of the thermal power plant.

Effects of magnetic fields on thermal convection in conductive aqueous solutions at ambient temperatures have been studied through heat transport measurements. The suppression of thermal convection...

By the accident of Fukushima Daiichi Nuclear Plant, all the nuclear plants have stopped in Japan. As a result, the operation rate of thermal power plants has been increased. It caused growth in CO 2 emission, which requires some kind of countermeasure. We focused on the iron oxide scales deposited on the piping system and boiler which declines the heat exchange efficiency of thermal power plants. In this study we attempt to remove the iron scales from the piping system and the boiler to maintain the power generation efficiency. In the current thermal plant treated by All Volatile Treatment (AVT) the iron elutes to the feed water in the low-temperature part which changes into iron ion or the paramagnetic fine iron oxide particles. On the other hand at the high-temperature part the main component of the scales is large ferromagnetic particles of magnetite. Therefore the magnetic separation at the high-temperature part is the more effective to remove the scale than that at the low-temperature part. For the reason, the existing method using the electromagnetic filter placed in the low-temperature part is not effective to remove the scales. We studied the high gradient magnetic separation (HGMS) at high-temperature part to remove a large amount of the scale. In this study, we assumed to install the HGMS system using the superconducting magnet at the inlet of the boiler.

The magneto-Archimedes separation allows for separating mixtures of feeble magnetic materials into its components based on the difference of their densities and magnetic susceptibilities. So far, this technique was applied for the separation of relatively large particles of several millimeters in diameter. Here we apply this technique experimentally to the simultaneous quantitative analysis of multiple micrometer-sized particles in a fluid. It was confirmed that the magneto-Archimedes separation can be applied for the separation of mixture of microspheres larger than 20 μm. Further high performance separation efficiency is expected with the optimization of separation conditions including the control of the spatial distribution of the magnetic field.

Particle swarm optimization (PSO) is a well-known instance of swarm intelligence algorithms and there have been many researches on PSO. In this paper, the author proposes an extension of PSO for solving fuzzy-valued optimization problems. In the proposed extension, genotype values (i.e. values in particle position vectors) are not real numbers but fuzzy numbers. Search processes in PSO are extended so that PSO can handle genotype instances with fuzzy numbers. The proposed method is experimentally applied to evolution of neural networks with fuzzy weights and biases. Experimental results showed that fuzzy neural networks evolved by the proposed method could model hidden target fuzzy functions despite the fact that no training data was explicitly provided.

The effect of high magnetic field on diamagnetic fluid flow has been studied by in-situ optical observation. The Schlieren optics utilizable under high magnetic fields was developed to carry out in-situ observation of the behavior of feeble magnetic fluids. Using a crystal of the diamagnetic aluminum potassium sulfate dodecahydrate, the behavior of the downward flow of high concentration solution in the sample dissolution process was observed. It was found that the direction of diamagnetic fluid flow was changed under spatially varied magnetic field. This phenomenon was understood qualitatively by considering the magnetic force acting on the high concentration solution and the surrounding solution.

Precise protein structure determination provides significant information on life science research, although high-quality crystals are not easily obtained. We developed a system for producing high-quality protein crystals with high throughput. Using this system, gravity-controlled crystallization are made possible by a magnetic microgravity environment. In addition, in-situ and real-time observation and time-lapse imaging of crystal growth are feasible for over 200 solution samples independently. In this paper, we also report results of crystallization experiments for two protein samples. Crystals grown in the system exhibited magnetic orientation and showed higher and more homogeneous quality compared with the control crystals. The structural analysis reveals that making use of the magnetic microgravity during the crystallization process helps us to build a well-refined protein structure model, which has no significant structural differences with a control structure. Therefore, the system contributes to improvement in efficiency of structural analysis for “difficult” proteins, such as membrane proteins and supermolecular complexes.

A quasi-microgravity environment appears in a high-field superconducting magnet bore where a large magnetic force counterbalances gravity acting on a diamagnetic substance. This suppresses convection of the diamagnetic solution in the crystallization cell placed in the bore from which protein crystals precipitate. A 16 T class superconducting magnet has been developed with a special coil configuration; one of the component coils produces a magnetic field the direction of which is opposite to that of the other coils. Thus, a large magnetic field gradient occurs, creating a magnetic force large enough to levitate water and hinder convection. This magnet system is operated in persistent mode, which is adequate for a rather time-requesting crystallization process of proteins. Preliminary experiments have shown that the protein crystallization process is substantially retarded in the magnetic force field.

The magnetic chromatography (MC) is a very useful system for an ion and/or fine magnetic particle separation due to its strong magnetic field gradients in a very small flow channel. We have not only developed the MC system to separate the fine particles and ions, we have also developed the numerical analysis computer code based on the fluid dynamics and electromagnetism to investigate the separating characteristics and to optimize design of magnetic column. In this paper, we studied MC technology for magnetic particles and ion separations using micro-scale magnetic column with ferromagnetic wires experimentally. The influences of the strength of magnetic gradient, flow velocity and coefficient of viscosity of solvent were studied by the developed computer code.

Alumina with nanoholes was prepared by anodic oxidation of aluminium and subsequently the synthesis of Fe nanofibers was attempted using nanoholes in alumina as a template. Various Fe nanofibers were synthesized by electroplating into alumina templates and subsequent chemical treatments in mixed-acid solutions to remove the templates. Obtained Fe nanofibers had the dimension with 20 nm-30 nm in diameters and typically 500 nm-2 μm in length. Effect of anodic oxidation treatments for a template on the microstructure of Fe nanofibers was examined. The length of Fe nanofibers could be changed by modifying the synthetic conditions, such as anodic oxidation times and electroplating times.

In order to make sure the great potential of steelmaking slag as a new phosphorus resource, domestic phosphorus material flow in Japan including iron and steel industry has been investigated based on the statistical data on 2002. It has been demonstrated that phosphorus in the steelmaking slag is almost equivalent with that in the imported phosphate rock in the view points of the amount and the concentration. Phosphorus exists mainly in the form of calcium-phosphate or its solid solution with calcium-silicate rather than the FetO rich liquid phase in the slag and exhibits remarkable segregation in the solidified slag. If the strong magnetic field is applied to the crushed slag, precipitated calcium-phosphate solution phase can be separated from FetO matrix phase due to the large difference of each magnetic property. It has also been indicated by the Waste Input–Output model that the phosphorus recovery from steelmaking slag by the new process proposed in the present work has great environmental and economical benefits.

Phase relations in the Fe2O3-FeTiO3-TiO2 system were investigated by equilibrating synthetic samples in evacuated sealed quartz tubes at a temperature of 1373 K. The equilibrium partial pressure of oxygen was measured by the electromotive force (EMF) method in the temperature range of 1273 to 1373 K. The phase diagram and oxygen partial pressure diagram in the titanium-iron-oxygen ternary system were then constructed at 1373 K. Rutile extraction from natural ilmenite ore was discussed from the thermodynamic viewpoint. It is found that rutile can be produced from common natural ilmenite ores not only by the reduction as the conventional titanium-rich slag process but also by an oxidation. Then, the oxidation experiment was conducted in air using Australian ilmenite ore to obtain rutile as one of the coexistent phases. Magnetic separation and leaching experiments for synthesized pseudobrookite and reagent rutile were conducted to confirm the possibility of separation of rutile from pseudobrookite. A new rutile extraction process was then proposed.

A computational fluid dynamics (CFD) model was developed for High Gradient Magnetic Separation (HGMS) of particles in liquids flowing through magnetic filters. Using this model, we simulated the effect of fluid flow, magnetic forces, and particle diffusion on the particle filtration efficiency in an HGMS liquid particle filter. By simulating capture efficiency of the simple configuration, the overall filtration efficiency of HGMS filters can be determined. This paper describes this numerical model and simulation results for an HGMS liquid particle filter.

We have developed a high gradient magnetic separation (HGMS) system to remove arsenic from geothermal water and to supply hot water for public use by using a superconducting magnet. We attained the reduction of arsenic concentration to 0.015 mg/L that is less than the standard for discharge of 0.1 mg/L and slightly larger than the environmental standard of 0.01 mg/L in Japan. The system consists of a pretreatment process that adds extra magnetization to arsenic by chemical reaction, and a reciprocal HGMS filter using a superconducting magnet that extracts magnetized arsenic from the geothermal water. We present the experimental results of the removal system.

We aim to apply the superconducting bulk magnets to high gradient magnetic separation technique. Two bulk magnets are face-to-face arranged and a pipe stuffed magnetic filters composed of ferromagnetic wires is placed between the magnetic poles. We setup the magnetic separation system and test it using slurry mixed with hematite particles (Fe2O3). Y123 bulk superconductors are magnetized by the “IMRA” method (pulsed-field magnetization), and consequently a magnetic field of 1.59 T is generated at the center of 20 mm gap between the magnetic poles. As a result of experiment on the magnetic separation, hematite particles of over 90% were removed from slurry at the flow rate of 2 l/min.

An intense magnetic field generator yielding 3.15 T in the open space between the magnetic poles has been constructed by using a pair of melt-processed bulk superconductors as trapped field magnets. The field was measured in a 2 mm gap between the magnetic poles set face-to-face after the pulsed-field magnetization “IMRA” method. This field generator is composed of Sm-based 123 compounds, vacuum pumps, pulsed-field coils and GM refrigerators with compressors. The system can be used in various applications. We investigated, for instance, the application to a high gradient magnetic separation system. It was found that the alpha hematite fine particles mixed in the flowing water was completely removed by this technique which was operated in the field of 1.7 T in the gap of 20 mm.

A superconducting permanent magnet system capable of generating strong magnetic fields has been constructed by using melt-processed bulk superconductors as trapped field magnets. The trapped field in the open space between two magnetic poles that are set face to face has reached 3.15 T when magnetized by a pulsed-field magnetization (PFM) technique. That was operated at 30 K attained by GM-cycle refrigerators. The performance exceeds that of conventional rare earth magnets or large scale electromagnets by far. It was found that the iteratively magnetizing pulsed field operation with reducing amplitude (IMRA) method is very effective in magnetizing the bulk superconductors. The magnet system can be used as a high field generator in various applications.

Our research is to magnetize the high-T/sub c/ bulk superconductors and to supply magnetic field environment realized by superconducting bulk magnets to various applications. In this paper, we aim to apply the superconducting bulk magnets to the high gradient magnetic separation (HGMS). Using a face-to-face type superconducting bulk magnet system in which a pair of bulk superconductors are oppositely arranged, Y123 bulk superconductors are magnetized by the "IMRA" method (pulsed field magnetization), and consequently, a magnetic field of 1.6 T is achieved between the magnetic poles. Next, HGMS using superconducting bulk magnets is demonstrated. A separation pipe into which filter matrices composed by ferromagnetic wires are stuffed is set between the magnetic poles and the slurry mixed with fine powder of /spl alpha/-hematite (Fe/sub 2/O/sub 3/) particles is flown. As the results of HGMS, over 90% of the Fe/sub 2/O/sub 3/ was separated. Moreover, separation filters have to be washed so that they are not clogged with captured particles. We confirmed that the filter was briefly washed by flowing water after moving the separation pipe from magnetic poles.

We have developed a superconducting High Gradient Magnetic Separation (HGMS) system to remove endocrine disrupters from water. The system was able to purify 70 L of endocrine disrupter-polluted water within about 10 min without generating any secondary waste. The system consists of pretreatment processes to form magnetized compounds with endocrine disrupters, and an HGMS device to extract them from water by using a strong magnetic force. We produced novel adsorbent made of micron-sized ferric oxide particles that are not only magnetic but also hydrophobic. Because some endocrine disrupters are hydrophobic as well, the ferric oxide particles adsorb endocrine disrupters eluted in water according to hydrophobic interaction. We succeeded in decreasing bisphenol A concentrations in the fortified water from 69 to 16 ng/L and nonylphenol from 7.0 to 0.9 mg/L. Furthermore, we have successfully demonstrated that we could regenerate the ferric oxide particles, so that they can be re-used for adsorption of endocrine disrupters in water.

本報告は，高勾配磁気分離を用いて水中のEDCsを大量・高速に浄化可能なことを実証したものである．著者らは，EDCsを水中から除去する目的で超伝導磁石による強力な磁気力を利用した高勾配磁気分離システムを開発した．このシステムは二次廃棄物を出さず，かつ高速除去が可能という特長を持つ．システムはEDCsに磁性を持たせる前処理と，磁気力を用いて除去する高勾配磁気分離装置で構成される．前処理には著者らが開発した疎水性を持つ強磁性酸化鉄微粒子を用いた．システムの原理は以下のとおりである．EDCsの多くは疎水性を持つので，疎水性表面を持つ微粒子を近づければ，疎水性相互作用によりそこへ吸着する．この微粒子に磁性があれば磁気分離が適用でき，汚染水を浄化することができる．実験では水中のビスフェノールAを69 ng/lから16 ng/lに，ノニルフェノールを7.0 mg/lから0.9 mg/lに減少できた．かつ，EDCsを含む約70 lの水を10数分間という短時間で浄化できた．更にEDCsを吸着した強磁性酸化鉄微粒子を再生し再利用できることも示した．

We measured the removal efficiency of hematite (Fe/sub 2/O/sub 3/) and iron (III) hydroxide (Fe(OH)/sub 3/) fine particles suspended in water in a high gradient magnetic separation (HGMS) system. Fe/sub 2/O/sub 3/ and Fe(OH)/sub 3/ have relatively small magnetic relative susceptibilities (MKS) near 10/sup -3/ and average particle diameters near 1 /spl mu/m. We demonstrated that HGMS is able to effectively separate weakly magnetized particles.

We are developing a water processing system for the removal of arsenic from geothermal water. We adopt the coprecipitation method of Fe (III) hydroxide, in which As is adsorpted to the flocks of Fe (III) hydroxide, and the High Intensity and High Gradient Magnetic Separation (HIHGMS) by superconducting magnets to extract the flocks. We demonstrated that the method reduce arsenic to 0.015mg/L that closed to the environmental standard in Japan, from 3.4mg/L and we purified a large amount of water at high speed. We also describe an estimate of a feasible plant for removal of arsenic in the geothermal water for public use.

Our objective was to apply superconducting bulk magnets to a magnetic separation technique. A pair of Sm123 bulk superconductors were magnetized by the “IMRA” method and arranged opposite each other with a gap of 20mm. The maximum flux density at the surface of the magnetic poles containing the bulk magnets and at the center of the gap of the poles was 2.26T and 1.76T, respectively. We set up a magnetic separator by placing a pipe between the magnetic poles of face-to-face superconducting bulk magnets and conducted experiments for two types of magnetic separation: high gradient magnetic separation (HGMS) with the use of a stainless steel filter, and open gradient magnetic separation (OGMS) without filters. The former uses separation filters composed of ferromagnetic wires stuffed into a glass pipe, and therefore a high gradient magnetic field is generated near the wires. The latter does not use filters. The separation ratio is investigated by the experiments using water mixed with fine powder of Fe3O4 and the performance of about 100% is achieved in HGMS.

Genetic algorithm (GA) employs real numbers (or bit strings) as genotype values for solving real-valued optimization problems. The author previously proposed an extension of GA. The proposed method extends the processes of GA to handle fuzzy numbers as genotype values so that GA can be applied to fuzzy-valued optimization problems. The author has applied the FGA to the evolution of fuzzy-valued neural networks (FNN) and showed that FGA could evolve FNNs, which model fuzzy functions well, despite that the training (evolution) of the FNNs was not supervised. In the previous paper, fuzzy numbers as the genotype values were symmetric triangular ones. Each symmetric triangular fuzzy number can be specified by its lower and upper limit values or its center and width values, and thus the FGA can employ either of two models, the lower and upper (LU) model or the center and width (CW) model for specifying genotype values. Ability of the FGA in searching solutions may depend on the model, because the crossover and the mutation operations for the fuzzy genotypes with the LU model are slightly different from those operations with the CW model. In this paper, the author compares the two models to investigate which model contributes better for the FGA to find better solutions. Application of the FGA is evolutionary training of the FNNs. An experimental result shows that the CW model contributed slightly better than the LU model in evolving FNNs which model fuzzy functions.

A single-phase voltage-doubler rectifier, which has two auxiliary bidirectional switches, is studied. The proposed rectifier has the advantages that the imbalance of the voltages across the capacitors, connected in series, is minimized independent of the working conditions and the discharge of capacitors is adjusted by arranging two auxiliary bidirectional switches. Therefore, the total capacitance of the rectifier can be reduced. The tested setup, using four insulated-gate bipolar transistors (IGBTs) and a microcomputer as a PI control-ler, is implemented and IGBTs are switched with 20kHz, which is out of audible band. Moreover, a rigorous state-space analysis is introduced to predict the operation of the rectifier. From the results, the well-balanced capacitor voltages can be achieved and the input current can be sinusoidally waveshaped with a near-unity power factor under the steady state and transient conditions even if the rectifier is operated with small series-connected capacitors. Consequently, the single-phase voltage-doubler rectifier studied is suitable for AC-DC conversion equipment with output voltage higher than twice that of the supply and with reduced total capacitance.

A full system of 1 kWh/1 MW superconducting magnetic energy storage (SMES) has been completed early this year. This SMES is the first step to the realization of practical SMES system for power line stabilization. Main points in its design are two module type arrangement of six coils having three coils and one converter as one unit of module, modified-D-shaped coils with mechanical supports, liquid helium vessel type cooling of coils, and high-temperature superconducting current leads. The first test experiment was carried out on the site recently. The above design points were examined. A preliminary test for power line control was also made in the distribution line at the site. Satisfactory results were obtained.

Single-phase buck-boost rectifier with minimized input current distortion is studied in the paper. To sinusoidally waveshape the input current with a near-unity power factor over a wide variety of operating conditions, the output capacitor is operated with voltage reversibility for the supply by arranging the auxiliary diode and power switching device. Then the output voltage is superposed on the input voltage during on-time duration of power switching devices in order to minimize the input current distortion caused by the small input voltage when changing the polarity. The tested setup, using two insulated-gate bipolar transistors (IGBTs) and a microcomputer, is implemented and IGBTs are switched with 20kHz, which is out of the audible band. Moreover, a rigorous state-space analysis is introduced to predict the operation of the rectifier. The experimental and simulated results confirm that the input current can be sinusoidally waveshaped with a near-unity power factor and a satisfactory output voltage regulation can be achieved.

The dynamics of power systems contain the nonlinearities such as trigonometric functions and the parameter uncertainties of reactances of transmission lines caused by short circuit faults. Wang et al. proposed an adaptive nonlinear controller for a single generator connected through two parallel transmission lines to an infinite bus. They employed the feedback linearization technique and the linear adaptive control technique to estimate the line reactance and the infinite bus voltage. Wang et al. used the estimator by integrating the relative speed and called it δ-detector. However, they did not discuss the stability of parameter adjustment law in using δ-detector, we propose an adaptive identifier with δ-detector which guarantees the practical stability, by employing the adaptive parameter adjustment law based on a Riccati equation.

The authors are planning to build a 1 kWh/1 MW (maximum stored energy/maximum power capability) module-type SMES (named ESK; experimental SMES of Kyushu Electric Power) as a first step towards the realization of practical SMESs for power line control. The main points of the design are those of: module-type coils for the development of SMES capacity scale-up; the choice of low loss stranded cables for reducing pulse operating loss; the choices of modified D shape coils and the reduction of stresses in the conductor-which become more serious in scaling-up and high-T/sub c/ superconductor (HTSC) current leads for covering weak points due to thermal loss in a module-type SMES which need many current leads. Some other points are also studied such as the design of the cooling system in which a single coil quench does not induce that of others, and harmonics suppression in the SMES power converter system.

Aluminum stabilizer, which is used in composite superconductors, in external fields at 4.2K prvides a remarkable enhancement of magnetoresistance as compared to predictions by conventional theory. In order to study the cause of this anomalous behavior, we measured the electric resistivities of copper-clad aluminum conductors having rectangular cross-sections in various magnetic fields at 4.2K. The measured values depend on the magnitude and orientation of the applied magnetic field with respect to the sample; the resistivity being several times larger for a parallel field. We calculated the current distributions in the conductors by solving Maxwell's equations, taking the Hall effect into consideration for evaluating resistivities. The predicted resistivities were consistent with our experimental results, leading us to conclude that the current caused by the Hall effect is the main origin of the anomalous magnetoresistance and its anisotropy. Finally, we discussed a method to reduce the anomalous resistivity.

Magnetic chromatograph is a techniques that use magnetic force to separate small particles. It is interesting because the magnetic column can be used repeatedly and does not produce secondary wastes. In order to increase the efficiency of the separation, the magnetic force is desired to be as large as possible. The magnetic force increases in proportion to the magnetic field gradient, and when the source of the magnetic force is a wire, the magnetic field gradient increases in inverse proportion to the diameter of the wire. Therefore, it is estimated that an assembly of ferromagnetic nano-wires can produce large magnetic force. Anodized porous alumina has ordered and uniform nanometer-sized hole arrays. Various materials including ferromagnets, such as Fe, Ni and Co, can be easily electrodeposited from the bottoms of the holes, and the holes can be filled with nano-wires. These ferromagnetic wires have nano-meter sized diameters. Therefore, they are assumed to be able to produce strong magnetic force. We propose to apply ferromagnetic nano-wires in porous alumina arrays to magnetic force generators for magnetic chromatograph.

The author previously proposed an extension of particle swarm optimization (PSO). The proposed method extends the processes of PSO to handle interval numbers as genotype values so that PSO can be applied directly to interval-valued optimization problems. The interval PSO (IPSO) can employ either of two interval models, the lower and upper model or the center and width model, for specifying genotype values. Ability of the IPSO in searching for solutions may depend on the model. In this paper, the author compares the two models to investigate which model contributes better for the IPSO to find better solutions. IPSO is applied to evolutionary training of interval-valued neural networks. A result of preliminary study indicates that the CW model is slightly better than the LU model and both models contribute well: the IPSO with the LU/CW model could evolve neural networks with a small error.

The author proposes an extension of particle swarm optimization (PSO) for solving interval-valued optimization problems and applies the extended PSO to evolutionary training of neural networks (NNs) with interval weights. In the proposed PSO, values in the genotypes are not real numbers but intervals. Experimental results show that interval-valued NNs trained by the proposed method could well approximate hidden target functions despite the fact that no training data was explicitly provided., {"references":["H. Ishibuchi, H. Tanaka and H. Okada, An architecture of neural \nnetworks with interval weights and its application to fuzzy regression \nanalysis, Fuzzy Sets and Systems, vol.57, no.1, pp.27-39, 1993.","D.B. Fogel, L.J. Fogel and V.W. Porto, Evolving neural networks, \nBiological Cybernetics, vol.63, issue 6, pp.487-493, 1990.","X. Yao, Evolving artificial neural networks, Proc. of the IEEE, vol.87, \nissue 9, pp.1423-1447, 1999.","K.O. Stanley and R. Miikkulainen, Evolving neural networks through \naugmenting topologies, Evolutionary Computation, vol.10, no.2, \npp.99-127, 2002.","D. Floreano, P. Durr and C. Mattiussi, Neuroevolution: from architectures \nto learning, Evolutionary Intelligence, vol.1, no.1, pp.47-62, 2008.","H. Okada, Proposal of fuzzy evolutionary algorithms for fuzzy-valued \ngenotypes, Proc. of International Conference on Instrumentation, Control, Information Technology and System Integration (SICE Annual \nConference) 2012, pp.1538-1541, 2012.","G. Alefeld and J. Herzberger, Introduction to Interval Computation, \nAcademic Press, 1983."]}