Single crystal of nonlinear optical crystal CsB₃O₅ (CBO) which has good properties for deep ultra-violet (UV) generation was investigated, and some optical properties were measured for the first time. In this report, the growth conditions were experimentally established. Single crystals with good optical homogeneity were obtained when the rotation rate of crystal was faster than 30 rpm. This phenomenon was explained by considering growth phenomena of segregation effect. Large single crystals were grown by a top seeded solution growth with the established conditions. The size of one of these was a×b×c=45×41×44mm³. Optical absorption edges at UV and IR regions were measured quantitatively to be 168 nm and 3400 nm.

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We demonstrated low noise blue SHG (Second Harmonic Generation) light by a single mode oscillation for intracavity frequency doubled laser diode (LD) pumped Cr dope LiSrAlF₆ (Cr:LiSAF) solid state laser. The SHG crystal used LiB₃O₅ (LBO). A birefringent filter and an etalon plate were used for single mode of Cr:LiSAF laser oscillation wave. The maximum blue SHG output power obtained 32 mW by using 1mm thickness of birefringent filter and 20% reflectivity 200 μm thickness of an etalon plate. The oscillation wavelength is changed with 0.24 pm/hPa for atmospheric pressure. The long term stability showed 300 hours by the cavity inserted into pressure box.

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We have developed a new rare-earth calcium oxyborate crystal Gd_xY_1-xCa₄O (BO₃)₃ (GdYCOB) in order to control the birefringence in nonlinear optical crystal. This GdYCOB has been grown by the Czhocralski technique. In addition, we have succeeded to generate noncritically phase-matched (NCPM) second and third harmonic of Nd:YAG laser radiation. Though, we observed two types of photo induced damage in high power third harmonic genaration (THG). we report the circumvention on these damage by elevated crytal temperature and THG performance in GdYCOB crystal.

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We have developed an all-solid-state deep-ultraviolet (DUV) coherent source based on sum-frequency-mixing (SFM) of two single-frequency lasers operating at a 5kHz repetition-rate. The system consists of a CW diodepumped, Q-switched Nd:YLF laser operating at 1047nm, a Ti:sapphire laser at 785-nm, and cascading SFM stages. The system generated 16.2W of 349 nm and 3.4W of 241.6nm as the intermediate outputs. By using a temperature-tuned CLBO crystal for the final mixing stage, 1.5W of 196.3nm output was produced. The linewidth of the DUV output was measured to be less than 200MHz.

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We have analyzed the relation between the conversion efficiency of CLBO crystal for fourth-harmonic generation of Nd:YAG laser and the effect of frequency-conversion parameters such as peak intensity, crystal length, and so on. We have found that the conversion efficiency of CLBO crystal is interrelated with the product of input average intensity and crystal length. It has been theoretically confirmed for the first time that this interrelation is caused by the thermal dephasing. By use of this theoretical examination, we have generated 20.5-W UV output power by fourth-harmonic generation of Nd:YAG laser in a CLBO crystal. This value is, to our knowledge, the highest UV power generated in all-solid-state lasers.

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We propose a power stabilizing method on SHG blue laser consisting of a quasi-phase-matched second harmonic generation (QPM-SHG) devise and a tunable distributed Bragg reflector laser diode (DBR-LD) by controlling the wavelength of a DBR-LD. The control algorithm for realizing low electric-power consumption was constructed. The wavelength of a DBR-LD is controlled within the phase-matching wavelength allowance range of the QPM-SHG device. The power fluctuation of blue light within ±3% was attained.

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Effect of ion beam etching on UV damage resistance was investigated in CsLiB₆O₁₀(CLBO) crystal. In high-power UV lasers, these optical surfaces were damaged due to absorption of the polishing compound embedded inside the surface. From SIMS analysis, the polishing compounds were found to be embedded in the CLBO surfaces to a depth of 60 nm. These polishing compound could be removed by using Ar ion beam etching. No ion beam-induced surface damage was observed when the applied ion beam voltage was 200 V. The lifetime of CLBO surface for the fourth-harmonics generation of Nd:YAG laser (266 nm, 20 ns, 4 kHz) was measured on etched sample. Etched CLBO surface exhibits an improvement lifetime 4 times longer than that of as-polished surface.

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The earth potential difference (EPD) signals have been observed continuously to monitor the naturally induced earth current together with some meteorological elements at Sado island in the Japan Sea. All these signals were transferred into digital recorded data with 1 s sampling time over one winter season. The EPD signals have no variation in a period of no wind, however, multi-trained pulse signals are observed in a period of strong wind. It is revealed that like this EPD variations occur when the wind speed exceeds the threshold value of 20 m/s. The streaming potential effect might be generated under the ground caused by strong wind over the ground surface.

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One fundamental problem in two-mass positioning systems is suppression of disturbance inputs, which are applied to the motor and the outputshaft. For example, apoor suppression results in degradation of positioning performances. In this paper, two-degree of freedom control for a two-mass positioning systemwith small inertia ratio is described. The control system consists of a state feedback controller (SFC), a sliding mode regulator (SMR) and an adaptive feedforward controller (AFC). The objective of the SFC is to suppress the vibration for the reference input and the step disturbance to the output shaft. The SMR is used to restrain the influence of the disturbance to the motor. The parameters of the AFC are adjusted by an adaptation law so that the tracking error converges to zero. The responses of the proposed positioning system for some disturbance inputs are measured. The experimental results demonstrate the effectiveness of the proposed system.

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This paper considers the quadratic stabilization of nonstandard singularly perturbed systems with uncer-tainties such that the so-called “matching conditions” are not satisfied. The construction of the stabilizing controller involves solving a certain algebraic Riccati equation with small parameter ε<0. The main result in this paper is to propose a new recursive algorithm to solve the above equation and to find an ε independent sufficient conditions for the existence of the full-order stabilizing controller. One noteworthy advantage of the Riccati equation approach to obtaining a stablizing controller is that the uncertain matrix. A₂₂+ΔA₂₂(r₂₂(t)) has unstable mode. Thus, our new results are applicable to both standard and nonstandard uncertain Singularly perturbed systems. To show the effectiveness of the proposed algorithm, numerical examples are included.

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Virtual Reality technology has been studied actively because of its remarkable merits, such as user's interaction to contents and sense of high immersion, which are not provided with other information media so far. However, high cost of contents producing and low reality of contents reflection are considered as problems. To remove these, an approach, Image-based Rendering, has been proposed, which utilizes real photograph directly to construct a 3D virtual space instead of geometry modeling. But this approach can not be available for industrial use, such as visual or engineering design, because this approach aims at walk-through observation to virtual spaces mainly. Accordingly, we studied a new technique which is based on the geometry modeling with merits of the Image-based Rendering, that is, high reality and low cost of producing. This technique consists of following sequence. At first, user assumes a hexahedron in a real indoor space. Second, user takes six photographs corresponding to inner surface of the hexahedron. Finally computer process with some simple user operation generates a 3D virtual space from these photographs semi-automatically. We examined our technique by error evaluation of calculated sizes and image quality, and also tried to apply it to our virtual reality software, the elevator renovation sales assistance system.

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This paper presents a design method for multi-input single-output nonlinear adaptive digital filters using neural networks. By applying neural networks in the field of adaptive signal processing, we propose in this paper a design method for parallel nonlinear adaptive digital filters using back-propagation training of parallel connected several small-scale feedforward multilayered neural networks, in order to design the nonlinear adaptive digital filter required for real time processing with many parameters. Furthermore, in comparison with this method and the method based on conventional linear theory, if proposed method is used, a good result can be obtained. and, it is possible that the learning efficiency is improved, because the parallel learning is carried out in this method. Finally, the results of computer simulation are presented to illustrate the effectiveness of the proposed method.

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Recently various kinds of coals which have, for example, heavy slagging or slowly burning properties are required to be fired in boilers at power stations. In addition, large capacity coal fired boilers shall not be exceptions to the frequent load swinging duties in the near future. The key to complying the requirement is the boiler controlling technique adaptive to the coal grindability, burning profile and the thermal conductance through the slagging. Thus, an advanced boiler controlling technique, which is coping with the dispersion in the coal characteristics, being considerable even though from the same mine, and the fluctuations in the thermal conductance through the slag adhering to and coming off the boiler heating surfaces has been developed and applied to a 1000 MWe thermal power station. In this report, not only an outline of the newly developed controlling technique which features the pulverizers dynamics model and the acoustic gas temperature measurement but also validations of its accuracy and usefulness are introduced.

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This paper develops a new Lyapunov recursive design for the model following control problem of rigid-link electrically-driven robot manipulators. The novelty is in the strategy to construct such a Lyapunov function recursively that ensures not only stability of a model following error system but also an L₂-gain constraint for the model following performance. First, the system dynamics are linearized by using geometric techniques. Then, the penalty signal for model following error between the outputs of the manipulator system and a reference model is introduced and the model following performance is evaluated by L₂-gain from the reference signal to the penalty signal. A state feedback control law is designed recursively such that the error system is globally exponentially stable with the L₂-gain less than any given small level. Experimental works were carried out for tracking control of a two-link electrically-driven manipulator. The results show the effectiveness of the proposed control scheme.

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This paper describes a neuron model with interaction among synapses. This model is based on the morphogenesis of dendrite and the nonlinear interactions between excitatory and inhibitory synapses on dendrite in retinal ganglion cells, which were not considered in traditional neuron models. The neuron model consists of a three-layer network: connection layer, AND layer and SOMA layer. The nonlinear interactions are idealized to be logical AND operations and neuron cells to be logical OR operations. The types of inputs from other cells are described as a connection function and determined by a back-propagation based learning. We can know the morphogenesis of dendrite, the location of synapses and the types of the synapse's connection from simulations on learning. Simulations show that this model can learn Exclusive-OR problem and other complicated problems with only one neuron.

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For automatic replacement of old plants' sequential controllers to modern programmable logic controller(PLC), we had proposed Sequential control Programs Automatic Inductive Regeneration method(SPAIR) from input-output signals and action specifications of a target controller. However, this method cannot regenerate the logics including interior coils.
Therefore, we propose an efficient inference method of interior coils for SPAIR using Logic Part Attaching Algorithm. In this method, the target logic of interior coil is acquired by repeatedly selective attaching of logic part. We confirmed the effectiveness through applying to some sequential programs including interior logics.

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In this paper, we describe an approach for finding signboard information in a grey scene image and rectifying a distorted signboard image taken from a nonorthogonal viewing direction. First, signboards in scene images are detected using several heuristics of characters and character lines. Then, we attempt to compute the orientation of the camera relative to a detected signboard from a single view. Finally, we rectify the distortion of signboard images, making the recognition of characters under a wider range of viewing conditions much easier. We show experimental results that demonstrate the effectiveness of the proposed approach. Lastly, we present an application of the proposed method to robot navigation using signboards on walls and doors as landmarks, where we could navigate a mobile robot in indoor environments successfully. Using signboards in scenes as landmarks enables us to realize humanlike navigation and map generation, and also benefits human-robot communication.

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In this paper, we propose a fuzzy adaptive identifier of SISO systems with nonlinearities in their input terms using new adaptation scheme. First, we mention briefly the fuzzy basis function expansion and the fuzzy approximator. Next, a fuzzy model of SISO plants with input nonlinearities is derived. Moreover, an adaptive identifier of the fuzzy model is proposed using the adaptation law which does not require the strictly positive realness. Finally, the performance of the proposed fuzzy identifier is investigated by the MATLAB simulation.

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The effects of introducing a workflow system include improved work efficiency, reduced processing time (that is, turnaround time), standardized business processes, and paperless processing. However, no concrete methodology for quantitatively evaluating these effects has been established.
In this paper, by analyzing some examples of introducing workflow systems, we extracted the factors that influence the effects, and we used quantification theory type I to create a mathematical model for predicting the rate of reduction of processing time as an effect of introducing a workflow system. As a result, we extracted (1) the process improvement factor and (2) business process type before the introduction of the workflow system as the factors that influence the effects. Value of the multiple correlation coefficient shows that both factors have a great influence. It can be said that the estimation model is effective because appropriate predictors are obtained within the error for the prediction by evaluating the residual for verification sample data. This means that before introducing a workflow system, we can predict quantitative effects of that system based on qualitative data

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Beef marbling is the most important determinant of meat quality being adopted in Japan. Beef marbling is being evaluated by means of the fat content and the distribution of fat particles in accordance with the 12-category Beef Marbling Standard(BMS). Grading is being performed through the subjective experience of graders by visual inspection. In this paper, a practical on-line beef marbling grading system that can support graders by automatically quantifying beef marbling is being presented. For the practical usage of the grading system, it is being required that particular attention be paid to the robustness of the system as well as the ability for on-line processing. In order to satisfy these requirements, the proposed method is constructed from very simple algorithms, discriminant threshold selection method and run length processing. From the experimental results obtained, the usefulness of the proposed grading method has been confirmed.

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