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Nuclear fission is one of the most complex processes in nuclear physics, involving a strong interplay between nuclear structure and dynamics, as well as various many-body correlations and fluctuation effects. Systematically theoretical and experimental research on the fission problems is of great significance to clarify the fission mechanism, reveal the complexity of low-energy nuclear dynamics, and test the nuclear model theory based on the nuclear many-body theory. However, despite the huge theoretical effort pursued by several generations of physicists, many crucial facets of this process are still not understood at a fundamental level, warranting further exploration of its dynamics. This is more so when viewed from the microscopic theoretical point of view. In the subject of study on nuclear fission, scission dynamics represents one of the most challenging problems in many-body theory as it plays a crucial role for determining the main properties of fission fragments and the emitted light particles. In the scission and post-scission processes, the fragments can experience a rapid change in shape and thus trigger the non-adiabatic effects coming from couplings between collective and intrinsic degrees of freedom. Therefore, from microscopic point of view, a reasonable description of the entire fission process could be achieved with an adiabatic model describing the slow evolution across the barrier, followed by a non-adiabatic treatment of the scission and post-scission dynamics. In this paper, with the aid of the nuclear mean-field model and Gogny effective nucleon-nucleon interaction, a three-dimensional Cartesian mesh code of time-dependent Hartree-Fock-Bogoliubov theory (Gogny-TDHFB Code for Fission) has been developed for solving the static and/or dynamic equations with isolated or periodic boundary conditions and no further symmetry assumptions. In contrast with the Skyrme HFB, the particle-hole channel and the particle-particle channel are treated on an equal footing in the HFB calculations with the Gogny interaction (Gogny HFB). The code consists of two parts: One is the constrained HFB for calculating the adiabatic fission potential energy surface in the multi-dimensional collective phase space, the other is TDHFB for studying the dynamical process of nuclear fission. In order to describe the extremely large deformation of nuclei in the direction of fission, the basis functions in the spatial grid points of the Lagrange mesh are introduced with respect to the direction of the z -axis, and the deformation harmonic oscillator eigenfunctions are used as the basis functions in the ( x , y ) directions. In the calculation of multi-dimensional potential energy surfaces, the constraints are imposed on expectation values of the multi-pole moments Q lm and the augmented Lagrangian method (ALM) is exploited for multi-constrained calculations. A parallel interface using the message passing interface (MPI) library has been implemented for large-scale calculations on massively parallel computers. Under the help of Gogny-TDHFB Code for Fission and by mainly focusing on the scission process, various aspects including the nuclear fission processes, the multi-dimensional potential energy surface, the configuration of scission point, more importantly, the non-adiabatic dynamics in the course of deformation from saddle to scission and also in post-scission are microscopically investigated in order to make clarification on the fission mechanisms, the nature of scission and some other basic problems. As an example, the spontaneous fission process of 240Pu has been studied. The results on the non-adiabatic dynamics in the course of deformation from saddle to scission and also in post-scission show that the pairing correlation plays crucial roles in the scission dynamics of nuclear fission.

Background: The density-constrained time-dependent Hartree-Fock method is currently a tool of choice to predict fusion cross sections. However, it does not include pairing correlations, which have been found recently to play an important role. Purpose: To describe the fusion cross section with a method that includes the superfluidity and to understand the impact of pairing on both the fusion barrier and cross section. Method: The density-constrained method is tested first on the following reactions without pairing, O16+O16 and Ca40+Ca40. A new method is developed, the density-constrained time-dependent Hartree-Fock-Bogoliubov method. Using the Gogny-TDHFB code, it is applied to the reactions O20+O20 and Ca44+Ca44. Results: The Gogny approach reproduces the experimental data well for reaction O16+O16 and Ca40+Ca40. The DC-TDHFB method is coherent with the TDHFB fusion threshold. The effect of the phase-lock mechanism is shown for those reactions. Conclusions: The DC-TDHFB method is a useful new tool to determine the fusion potential between superfluid systems and to deduce their fusion cross sections., SCOPUS: ar.j, info:eu-repo/semantics/published

International audience; In a mean-field description of superfluidity, particle number and gauge angle are treated as quasiclassical conjugated variables. This level of description was recently used to describe nuclear reactions around the Coulomb barrier. Important effects of the relative gauge angle between two identical superfluid nuclei (symmetric collisions) on transfer probabilities and fusion barrier have been uncovered. A theory making contact with experiments should at least average over different initial relative gauge-angles. In the present work, we propose a new approach to obtain the multiple pair transfer probabilities between superfluid systems. This method, called phase-space combinatorial (PSC) technique, relies both on phase-space averaging and combinatorial arguments to infer the full pair transfer probability distribution at the cost of multiple mean-field calculations only. After benchmarking this approach in a schematic model, we apply it to the collision O20+O20 at various energies below the Coulomb barrier. The predictions for one pair transfer are similar to results obtained with an approximated projection method, whereas significant differences are found for two pairs transfer. Finally, we investigated the applicability of the PSC method to the contact between nonidentical superfluid systems. A generalization of the method is proposed and applied to the schematic model showing that the pair transfer probabilities are reasonably reproduced. The applicability of the PSC method to asymmetric nuclear collisions is investigated for the O14+O20 collision and it turns out that unrealistically small single- and multiple pair transfer probabilities are obtained. This is explained by the fact that relative gauge angle play in this case a minor role in the particle transfer process compared to other mechanisms, such as equilibration of the charge/mass ratio. We conclude that the best ground for probing gauge-angle effects in nuclear reaction and/or for applying the proposed PSC approach on pair transfer is the collisions of identical open-shell spherical nuclei.

The interpretation of the new effect of the superfluidity in reactions with small number of particles is discussed in a simple model where the exact solution is accessible. It is find that the fluctuations of observable with the gauge angle reproduce well the exact fluctuations. Then a method of projection is proposed and tested to determine the transfer probabilities between two superfluid systems., Comment: 4 pages, 4 figures, proceeding of the FUSION17 conference

A numerical method to solve time-dependent Hartree-Fock-Bogoliubov equations by using a hybrid basis of two-dimensional harmonic oscillator eigenfunctions and a one-dimensional Lagrange mesh with the Gogny effective interaction is applied to head-on collisions of superfluid $^{20}\mathrm{O}$ nuclei. Taking the energies around the barrier top, the trajectories, pairing energies, and numbers of transferred nucleons are displayed. Their dependence on the relative gauge angle at the initial time is studied.

Plasma was generated in water by irradiation at high frequency of 13.56 MHz, and the behavior of bubbles including the plasma was observed by a high-speed camera. The generation pattern of the bubbles was classified into four types according to liquid temperature and supplied power. Conducting the simulation, the maximum temperature in the bubble was found to be from 3500 K to 4300 K, and the decomposition of water molecule occurred. The gas in the bubble was found to become high ratio of hydrogen. The phenomenon can be regarded as a film boiling of exceptionally high heat flux.

WINDS is the experimental communications satellite currently under joint development by Japanese Aerospace Exploration Agency (JAXA) and the National Institute of Information and Communications Technology (NICT). The high-speed satellite communication system is very effective for quick deployment of high-speed networks economically. The WINDS will realize ultra high-speed networking and demonstrate operability of satellite communication systems in high-speed internet. NICT is now developing high-speed satellite communication system for WINDS. High-speed TDMA burst modem with high performance TPC error correction is underdevelopment. Up to the DAC on the transmitter and from the ADC on the receiver, all modem functions are performed in the digital processing technology. Burst modem has been designed for a user data rate up to 1244 Mbps. NICT is developing the digital terminal as a user interface and a network controller for this earth station. High compatibility with the Internet will be provided.

On the basis of the symmetry-unrestricted, cranked Skyrme-Hartree-Fock (SHF) calculations, we discuss superdeformed (SD) rotational bands in (1) the 40 Ca region along the N=Z line, and (2) neutron-rich Sulfur isotopes up to the neutron-drip line. The calculation was carried out with the use of the three-dimensional (3D) coordinate-mesh representation without imposing any symmetry restriction. Stability of the SD bands against exotic deformations breaking both reflection and axial symmetries were carefully examined. The analysis indicates possible appearance of negative-parity rotational bands associated with octupole shape vibrational excitations built on the SD yrast band. We then present results of selfconsistent RPA calculation for such a new type of collective vibrational modes. The selfconsistent RPA calculations based on the SD local minima obtained by the SHF calculation were carried out by means of the mixed representation on the 3D Cartesian mesh in a box.

In this paper, we propose a new control method for two-wheeled non-holonomic mobile robots. Since the non-holonomic mobile robots has non-integrable constraint conditions, it is difficult to derive a control law so that the robots are convergent to the target state. The proposed method designs a nonlinear regulator carrying out asymptotic convergence of non-holonomic mobile robots to a given trajectory family. The trajectory family is chosen so that it passes through the origin and its gradient at the origin is equal to zero. As the result, the mobile robots are convergent to the origin as the target state while generating their path. We name this method Path-generating Regulator. Neither the coordinate transformation nor the input transformation is needed in this method unlike other methods. Global asymptotic regulation property of this method is proven by a Lyapunov-based stability analysis. By numerical simulations and experiments, we show the validity of the proposed method.

Metal removal performance of filter cartridge with bi-layered structure was investigated. The filter was prepared using UHMWPE and ion exchange membrane made by grafting polymerization. In filtration experiment, feed ultrapure water was controlled spiking of 15 metals at ppt level, and removal performance of each metal was determined using ICP-MS measurement of filtrate. Metal adsorption behavior for most of the metals were following the classical fluid dynamic theory and the boundary layer controlled reaction. The results were compared to conventional UHMWPE membrane filter and discussed for each metal.

We present a computational method to solve the RPA eigenvalue equation employing a uniform grid representation in three-dimensional Cartesian coordinates. The conjugate gradient method is used for this purpose as an iterative method for a generalized eigenvalue problem. No construction of unoccupied orbitals is required in the procedure. We expect this method to be useful for systems lacking spatial symmetry to calculate accurate eigenvalues and transition matrix elements of a few low-lying excitations. Some applications are presented to demonstrate the feasibility of the method, considering the simplified mean-field model as an example of a nuclear physics system and the electronic excitations in molecules with time-dependent density functional theory as an example of an electronic system.

Electroless nickel initial deposition and subsequent steady state deposition process on a nonconductor and conductor were investigated.It is indicated that phosphorus contents in the deposited films during the initial nickel deposition reaction were higher than the subsequent steady state deposited films. The plating baths containing acetic acid, propionic acid, succinic acid, malic acid, citric acid, glycine and aspartic acid as a complexing agent showed higher phosphorus in the deposited films.On the conductor, lactic acid and glycolic acid added bath showed the shortest induction time and deposited films readily changed to continuous films at the initial deposition steps. Also, it is confirmed that a bath exhibiting a higher deposition rate compared with a basic bath leads to extraneous particles during the initial deposition period.On the nonconductor, the morphology of initially deposited nickel was not a layer-by-layer structure on nonconductor, it is confirmed that deposited films are composed of fine particles. Also, particle sizes of nickel-phosphorus deposits ranged from 10 to 40nm.

The evolution of a state in a many-body system can be formulated in either Schrodinger picture or the Heisenberg picture.The evolution of the Heisenberg operator for a density matrix is given by the Liouville equation.The Liouville evolu- tion function has an analyticity that differs from the Schrodinger evolution function, because the Liouville eigenvalue equation yields the splitting of two energy eigenval- ues, while Schrodinger equation yields each of the energy eigenvalues.However, no method to exactly solve the Liouville evolution equation for a given Hamiltonian has yet been established.With regard to the splitting of two nearly degenerate energy eigenvalues in the context of collective tunneling transitions, we obtain an expres- sion for the energy splitting from the analytical structure of the spectral function for the Liouville evolution employing the projection operator method.The projection operator method for the Liouville equation is powerful for the purpose of analyzing the evolution of a density matrix. The projection operator method for the Liouville equation has been extensively applied to analyze the evolution of many-body systems. 1) The evolution of a system expressed in terms of time convolution is usually formulated to second order in the perturbation Hamiltonian. 2) When the second order calculation does not yield a rea- sonable result, however, it is necessary to develop an exact expression.In particular

Periodic input sometimes controls mechanical systems dynamically. We have investigated a pendulum system from a view point of such a dynamic control. In this paper, we present the motion control that stabilizes the pendulum to a desired limit cycle by a periodic input. In our method, the periodic input is added so that the energy of the pendulum may become the energy of the desired limit cycle, and is consisted of a periodic solution of van der Pol's equation which is inputted the angle of the pendulum. Experimental results support the effectiveness of the proposed method.

Electroless nickel plating is not initiated on the copper substrate since there is little catalytic action with respect to the oxidation reaction of sodium hypophosphite on the copper. Therefore, a palladium catalyst treatment is generally applied. However, the extraneous deposition of nickel on the resist or resin is often observed as a result of treatment with the palladium catalyst along with the shrinking of patterns.This research involved improving the selective deposition through the use of Dimethyl Amine Borane (DMAB) instead of the palladium catalyst. Selective deposition has improved with the addition of DMAB to the electroless nickel plating bath as a second reducing agent.The mechanism of the selective deposition on the copper through the use of DMAB in electroless nickel plating has been explained in this study.

An electro-graph test using zinc instead of cadmium was evaluated as a alternative porosity measurement method. This technique was effective in the porosity evaluation of electroless nickel plating on copper substrate.Pinholes of electroless nickel deposits produced on copper substrate by the conventional palladium catalyst process have been compared to direct electroless nickel plating on copper using DMAB as a second reducing agent.Results confirmed that fewer pinholes are produced on electroless nickel films when not using the palladium catalyst process than with films treated using the conventional palladium catalyst process. The direct electroless nickel plating films displayed excellent corrosion resistance.

The effect on genetically obese mice of a milk whey protein isolate (WPI) and soy protein isolate (SPI) and their hydrolysates (WPI-H, SPI-H) on the rate of body fat disappearance was investigated. Male yellow KK mice were made obese by feeding with a high-fat diet containing 30% fat from 6 to 10 weeks of age. They were then fed with an energy-restricted low fat (5.0%) and high protein (35% WPI, WPI-H, SPI or SPI-H) diet for 2 weeks at the 60% level of energy intake by mice on laboratory feed. During the weight reduction period, the body weight of the WPI, WPI-H, SPI and SPI-H groups changed by -9.1, -9.1, -10.0 and -11.1 g/14 days, respectively, the reduction being significantly lower in the SPI-H group than in the WPI and WPI-H groups. The plasma total cholesterol level was significantly lower with the SPI diet, and the plasma glucose level was lower with the SPI and SPI-H diets than with the WPI and WPI-H diets. Although the body protein content was comparable in all the groups, the body fat content was significantly lower with the SPI diet than with the WPI diet, and was also significantly lower with the SPI-H diet than with the WPI and WPI-H diets. The weight of the perirenal fat pads was significantly lower with the SPI-H diet than with the WPI and WPI-H diets. These results indicate that SPI and SPI-H are suitable protein sources in an energy-restricted diet for treating obesity.

This paper describes the research and development of an On-Board Processor (OBP) for a mobile satellite communications system using a geostationaly satellite. The system, which based on Multi-Carrier Time Division Multiple Access, can realize high performance and facilitate the use of miniature hand-held mobile Earth terminals. Our research and development results indicate as follows. 1. 1) The simultaneous-slot switching method will be the most suitable for an on-board base-band switching with consideration of traffic capacity, time delay, and hardware scale. 2. 2) The OBP performs channel exchange with regeneration that contributes to a reduction in the size of mobile terminals because of the coding gain. 3. 3) Many kinds of Application Specific Integrated Circuits are designed to realize large channel capacity and reduce the size and power consumption of the OBP. These OBP design can increase the channel capacity, which is equivalent to in 5.6kbps voice channel, up to over 500 channels within 5MHz frequency band Some results are applied to the OBP being developed for the Japanese Engineering Test Satellite VII (ETS-VB).

Timely input sometimes can control periodic movement of mechanical systems. In the swing which is the parametric excitation system, when the center of gravity is moved in double cycle, the swing's amplitude increases, and it decreases when this phase is moved π [rad] . But it is difficult to control a swing in the wide range, because the cycle of the swing depends on its amplitude. This paper shows that the van der Pol's equation inputted the swing's angular velocity can compose the frequency observer, and proposed the new control form of a swing that the center of gravity is moved by nonlinear feedback which consists of equation's output.

To find out how quantum bifurcation phenomena manifest themselves in the space of states, various periodic trajectories accompanied with several sets of bifurcated trajectories are studied for a simple quantum model Hamiltonian under a time-dependent mean-field approximation. Making use of the quantum-classical correspondence, a method of classifying the eigenstates and of visualizing the global structures of the whole space of eigenstates is proposed. By means of the profile functions of the eigenstates, appropriate sets of eigenstates representing the quantum correspondents of the bifurcations are found. The idea of quantum bifurcations is supported by similar behavior of the energy vs period time (E-T) plots of the periodic trajectories and the eigenstates.

Periodic stimulation sometimes stabilizes dynamic movement of mechanical systems. In this paper, we investigate the dish spinning trick from a view point of such a periodic stabilization. The system is simply described by using a spring-dumper model of the supporting rod which has two degree of freedom. In our analysis, the movement of the dish is stabilized when the elastic rod is shaken in higher frequency than its native resonant frequency. Our theory is checked by letting a robot play the real dish spinning.

This paper presents a searching algorithm and a tree-type two-dimensional representation of the environment for solving the path-planning problem of a mobile robot navigating in a known space. We propose: (i) a search algorithm that chooses paths by the number of turns needed to reach the goal and, from these, the best one in terms of distance and/or rotation angle, and (ii) a tree-type representation of the environment that results from considering obstacles to be enclosed by their peripheral rectangle and from defining different types of obstacles and vertices. This representation does not expand the obstacles to guarantee a collision-free solution as conventional methods do- a local reactive planner is used instead. Our proposal relies on the following two empirical facts. (i) Distance is not a priority in places where solution paths are relatively short - time and energy must be considered instead. (ii) Calculations are simplified when all obstacles have the same structure. To simplify the path-search...

A new numerical method of calculating the Hartree-Fock-Bogoliubov (HFB) and time-dependent HFB (TDHFB) with the Gogny interaction is proposed. The three-dimensional harmonic-oscillator (3DHO) basis functions are replaced by one-dimensional spatial grid points of Lagrange mesh plus two-dimensional harmonic-oscillator basis functions in the perpendicular plane to the direction of the spatial grid points [Lagrange mesh and harmonic oscillator (LMHO)]. By using the LMHO, the calculations of the HFB and TDHFB are carried out in the typical nuclei of ${}^{20}\mathrm{O}$ and ${}^{34}\mathrm{Mg}$ as an illustration of the feasibility of the TDHFB formulation with the LMHO. The strength functions of the quadrupole vibrations ($K=0$) are obtained and are compared with the ones calculated with the 3DHO.

As directed self-assembly (DSA) has gained momentum over the past few years, questions about its application to high volume manufacturing have arisen. One of the major concerns is about the fundamental limits of defectivity that can be attained with the technology. If DSA applications demonstrate defectivity that rivals of traditional lithographic technologies, the pathway to the cost benefits of the technology creates a very compelling case for its large scale implementation. To address this critical question, our team at IMEC has established a process monitor flow to track the defectivity behaviors of an exemplary chemo-epitaxy application for printing line/space patterns. Through establishing this baseline, we have been able to understand both traditional lithographic defect sources in new materials as well as new classes of assembly defects associated with DSA technology. Moreover, we have explored new materials and processing to lower the level of the defectivity baseline. The robustness of the material sets and process is investigated as well. In this paper, we will report the understandings learned from the IMEC DSA process monitor flow.

This study determined the effect of dietary (dipalmitoyl) triacylglycerol (TAG) structure on the absorption and metabolism of fat in the presence or absence of cholesterol. Sprague-Dawley male rats weighing approximately 180 g were fed diets containing 10 g/100 g diet 1,3-dipalmitoyl-2-oleoyl-glycerol-rich oil (POP) or 1(3),2-dipalmitoyl-3(1)-oleoyl-glycerol-rich oil (PPO), either with or without cholesterol supplementation (0.5 g/100 g diet), for 2 wk. There were no differences in the growth of rats fed the various diets. The apparent absorption efficiency of dietary fat especially the apparent absorption efficiency of palmitic acid, was significantly lower in the POP groups than in the groups fed the PPO diets. The excretion of cholesterol in feces of rats fed the POP diet with cholesterol was significantly greater than those fed the PPO diet containing cholesterol. The excretion of total bile acids in the rats fed cholesterol was significantly greater than in those fed the diets without cholesterol. Liver cholesterol was significantly greater in rats fed cholesterol and was not affected by the TAG structure. Plasma cholesterol was significantly lower in the POP dietary groups than in the PPO groups. These results suggest that the absorption and metabolism of fat depend on the positional isomer of the fatty acid.

We investigated the effect of dietary Ca on the absorption of 1,3-dipalmitoyl-2-oleoyl glycerol (POP), 1(3),2-dipalmitoyl-3-oleoyl glycerol (PPO), cocoa butter (CB) which contained 1-palmitoyl-2-oleoyl-3-stearoyl glycerol (POS) as major triglycerides, chocolate (Choco) made from cocoa butter and corn oil. Rats were fed the diets containing 10% of one of the above lipids for 7 days. The apparent absorption efficiency of nutrients, especially fat, were lower in rats fed CB+Ca or POP+Ca diet than those fed CB or PPO+Ca diet. The low apparent absorption efficiency of fat was due to the low absorption efficiency of palmitic and stearic acids. Absorbed fat energy was 10% lower in CB+Ca diet group than in CB diet group, and was 18% lower in Choco+Ca diet group than in corn oil diet group. Although the apparent absorption efficiency of energy was lower in Choco diet group than in corn oil diet group, the apparent absorption efficiency of palmitic and stearic acids in Choco were larger than those in cocoa butter even when Ca was fortified. The apparent absorption efficiency of Ca were lower in rats fed Ca-fortified diets than in Ca-non-fortified groups, however absolute amounts of absorbed Ca were not different among all the groups. The present results suggest that Ca-fortification decreased the apparent absorption efficiency of fat with long chain saturated fatty acids, particularly at 1,3 positions of glyceride, and the apparent absorption efficiency of saturated fatty acids in foodstuff such as chocolate were also decreased by Ca-fortification.

To visualize complex structure of the excited states in the many-fermion system, a profile function of the eigenstate within the quantum phase space is defined by using the boson expansion theory. When the anharmonic interaction is sufficiently weak where a corresponding semi-quantum system described by the time-dependent Hartree-Fock (TDHF) theory shows isolated resonant structure, there exists a remarkable similarity between the Poincare section map of the TDHF trajectories and the profile functions of the eigenstates. It is shown that these eigenstates are well understood by using a new concept of quantum nonlinear resonance. It is also shown that a pair of newly appeared states due to the quantum resonance is not associated with any dissolution in a number of the good quantum numbers.

The purification and some properties of two types of lipase (Lipase I and Lipase II) from Rhizopus niveus are described. The enzymes were purified to homogeneity by column chromatographies on DEAE-Toyopearl (1 pass) and CM-Toyopearl (2 passes). Lipase I consists of two polypeptide chains [a small peptide with sugar moiety (A-chain) and a large peptide of molecular weight 34,000 (B-chain)]. Lipase II has a molecular weight of 30,000 consisting of a single polypeptide chain. Lipase I appeared to be converted to Lipase II by limited proteolysis by a specific protease a small amount of which is in the culture supernatant from Rh. niveus, because one of the peptides formed has the same N-terminal sequence and C-terminal amino acid as Lipase II, as well as the molecular mass estimated by SDS-PAGE. Lipase I had a pH optimum of 6.0-6.5 and a temperature optimum of 35 degrees C, while, for Lipase II these values were pH 6.0 and 40 degrees C. Both enzymes were obtained in the crystalline state using the hanging drop method of vapor diffusion and PEG as the precipitating agents.

This paper describes a method to make a wheeled mobile robot follow a given path just like a driver would decelerate the speed of a car before a corner and accelerate it on the straight course of the road. Two kinds of velocity vectors are introduced to determine an optimal direction and speed of the robot in order to follow the path. The velocity defined as a function of curvature of the path is mainly utilized to change the speed of the robot along the path. The other velocity given as the tangent of a virtual potential function produces an attraction force toward the path. Path tracking control of the robot is formulated with current and future sets of these velocity vectors in a frame of the digital preview and predictive control. By this method, the robust tracking performance is achieved.

A simple communication network by microsatellites is studied. A few microsatellites pick up and deliver voice and some digital information from/to ground stations, and/or from/to satellites. 9.6 kbps and 1.2 kbps are used for the ground link and the inter-satellite link respectively with onboard digital processing techniques. It uses the formation of the microsatellites in one orbit, to widen the real-time communication area. The microsatellite is 50 kg of dumbbell shape with an expandable mast.

In this paper, the following two control methods are proposed for path tracking control of robot manipulators : (1) digital control method based on the principle of movement of a nonlinear mechanical system : (2) preview control method utilizing future information of the desired trajectory to improve the tracking control performance of method (1). The features are (a) systematically derived digital control law, (b) disturbance terms that may be unknown if they are functions of position and velocity. Finally, the effectiveness of the proposed control methods is shown by simulation studies and experimental studies.

In travelling crane systems, the load-swing sometimes has an oscillation component perpendicular to a travelling direction by accidental disturbances. This paper analyzes the dynamics of the load swing with the rope length as another control channel to the crane system and proposes a control strategy both to suppress the load swing and to control the trolley position. In the control, the rope length is variated to move the load upwards and downwards following to a sinusoidal function so that the swing direction of the load rotates. At the same time, the trolley is controlled to eliminate the oscillation component of the load growing in its travelling direction and to approach to a desired position of the trolley. The control is evaluated by numerical experiments and proved to be effective.

Enzymatic production of D-Glu was investigated by the succesive reactions of a glutamate racemase (EC 5.1.1.3) and a glutamate decarboxylase (EC 4.1.1.15) on L-Glu.Lactobacillus brevis ATCC8287 was chosen as a source of glutamate racemase. This strain produced a glutamate decarboxylase simultaneously. The glutamate racemase activity in the cell free extracts was 0.035 units/mg protein. The enzyme kept its activity even at 500 Mm of L-Glu (74g/liter). The optimum pHs of the racemase and the decarboxylase were at around 8.5 and below 4.0, respectively. Both enzymes had no activity at the optimum pH for the other enzyme. L-Glu was racemized first by the glutamate racemase at pH 8.5, then the pH was shifted to 4.0 at which L-Glu was decarboxylated by the glutamate decarboxylase. Starting from 100 g/liter of L-Glu, 50 g/liter of D-Glu was produced and no L-Glu remained in the reaction mixture.