The beam application to nanoscience, especially next generation lithography producing the semiconductor devices, is expanded by so-called quantum beam technology. EUV (Extreme Ultraviolet) lithography is now evaluated to be the best solution of the next generation lithography for 22 nm node and beyond 22 nm node. Recent progress in the development of EUV lithography, especially resist processes and materials, is supported by many kinds of beam technology such as pulse radiolysis.

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Since a phase locked loop (PLL) is used in the clock extraction of digital communication and high-density digital recording, it is required to have simultaneously low jitter, fast pull-in, and wide lock-in range characteristics. However, in the case of the conventional dividing ratio changeable digital PLL based on phase state memory and double clock-edge detection (PM-DCPLL), the output jitter in the steady state becomes no less than the half pulse width of the base clock controlling the loop, and the upper bound frequency of lock-in range is limited accordingly.
In this paper, we propose the dividing ratio changeable digital phase locked loop (MC-DCPLL) with low jitter, wide lock-in range and fast pull-in characteristics using the multi-phase clock divider. Since the output jitter of this circuit is the 1 phase difference of the multi-phase clock in a steady state. The circuit can thus reduce the output jitter to 1/k of that of conventional PM-DCPLL when the k phase clock is used. Therefore, the upper bound frequency becomes k times as high as that of conventional PM-DCPLL. Furthermore, the initial pull-in is completed in one period of the input signal by using the initial pull-in circuit.

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We propose a new design method of a class of FIR low-pass filters having steep cut-off with small number of taps. This is a significant improvement of our precedent result where desired frequency characteristics are realized by a set of frequency scalings of basic filters and their series connection. Though the method can realize an FIR filter with much smaller number of taps than conventional Remez method, the resulting characteristics can be such that their cut-off edges are not steep due to just the simple series connection of scaled filters. In this paper, we consider the series connection with each module consisting of a function of the basic filters. It turns out that the function can be written as a recursion with the basic filters, called mean operation. The mean operation is performed in such a way that the skirts of the transition region is subtracted recursively one by another to cancel the gradual slope, so that the resulting characteristics become steep. In a design example, the proposed method is compared with conventional ones and is shown to approximate a desired characteristics with smaller number of multiplies.

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Pulsed ultrasonic distance measurement systems are frequently used in robotics applications, thanks to their low cost and small size. The pulse compression techniques, originally developed by radar engineers, were adopted to eliminate frequent misreadings caused by crosstalk or external ultrasound sources. High-performance computing systems for the implementation of pulse compression techniques enable reliable and accurate distance measurement. In most cases however, they significantly increase the complexity of the total system, cutting down one of the advantages of ultrasonic systems. The ultrasonic ranging using a digital polarity correlator can overcome this drawback, because the cost of realizing delay and multiplication for each point on the polarity correlation function as a parallel operation is very low. This paper presents an analysis of the binary coded frequency shift keyed signals for the ultrasonic ranging using a digital polarity correlator. The spectra of the frequency shift keyed signals have been observed to be narrow compared with the spectra of the corresponding phase shift keyed signals. This suggests the possibility of a more reliable and accurate distance measurement with the frequency shift keyed signals in terms of occupied bandwidth.

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The theory of descriptor system (DS) has been studied intensively in recent years, but little attention was paid to study the model following control system (MFCS) for DS. In this paper, a design method of model following control system for nonlinear descriptor systems using stable assignment of invariant zeros is proposed. We can design nonlinear model following control systems whose inner states are bounded based on the consideration to separate the object system into a linear part and a nonlinear part. In model following control system zeros of linear part must be stable. It is desirable to remove the condition which is a constraint of design. We can remove that condition based on stable assignment of invariant zeros. Finally numerical simulations with disturbances verify the availability of this method.

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Among various control methods, model predictive control (MPC) becomes one of the major control strategies and has many successful applications. This paper presents an automatic tuning method of MPC using particle swarm optimization (PSO). One of the challenges in MPC is how control parameters can be turned for various target plants and usage of PSO for automatic tuning is one of the solutions. The tuning problem of MPC is formulated as an optimization problem and PSO is applied as the optimization techniques. PSO is one of meta-heuristic methods which are known to search a global optimum at a relatively high ratio and with no use of a gradient. The numerical results for simple examples show the effectiveness of the proposed PSO-based automatic tuning method.

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Recently, a high-speed communication network is rapidly developing. It is expected that the realization of networked control systems using the network infrastructure. In the networked control systems, data dropouts, which are occurred due to link failure and data collision, cause degradation of control performance, especially stability. In this paper, the networked control systems which have outward (plant to controller) and return (controller to plant) communication channels are considered. At first, in this paper, an estimation method of unknown and time-varying data dropout rate in the channel is developed. Next, feedback gain is dynamically adapted depending on the estimated dropout rate. Finally, the usefulness of the proposed method is demonstrated through some numerical examples.

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A method to construct optimal memoryless regulators of large scale systems with time-delays in the interconnections and the states is proposed. Each feedback gain of decentralized control laws is obtained directly from solutions of simultaneous linear matrix inequalities. Firstly, a sufficient condition for the stability of the overall closed loop system is presented. Then it is extended so that the overall system and each subsystem remain to be stable, even if all or some of interconnections between subsystems are cut. Lastly, a simplification of the implementation is discussed in perspective of a feedback loop reduction.

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We propose a novel maximum neural network with stochastic dynamics for solving NP-hard optimization problems, the N-Queens problems. A self-feedback term with stochastic characteristic is introduced into motion function of the maximum neural network, which increases the dynamics of the neural network to search for globally optimal solutions. Moreover, several new constraints having random selection character are presented and used in the proposed algorithm to drive the network to escape from local minima. With the stochastic dynamics and those new constraints, the proposed algorithm has a great ability to find optimal or near-optimal solutions of N-Queens problems. The simulations show that the proposed algorithm is superior to other algorithms in light of successful rate, and it is especially suited to be used in practical system with parallel updating.

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This paper describes a control method for a tripedal robot, which walks with a shufffle. The robot consists of three electromagnets and three piezoelectric elemens. The electromagnet supports the robot as a leg. Two ouf of three electromagnets adheres to an magnetic floor and the other electromagnet moves by the deformation of the piezos. The relation between the control waveforms and the robot motion is described theoretically. The theoretical displacement of the robot is calculated. The piezo deformations which move the robot to the destination are obtained. The control waveform is determined by the piezo deformations.

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In this paper, we propose a system for recommending tags of images. The proposed method presents to its user various tags with high precision by taking into account both the co-occurrence of tags and tags of similar images. Additional search with the user feedback enables us to find some new tags relevant to the image of interest. In order to test the proposed method, we compare it with a method based only on the co-occurrence of tags, as well as a method based only on the similarity of images. From the experimental results using 16002 images, we have confirmed that the proposed method is capable of finding more tags as compared to the methods for comparison. We have also confirmed that the additional search is effective to find additional tags.

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Adaptive Window-Skipping Method (AWS) is known as the fast template matching algorithm. This method can reduce the computational cost using similarity between subtemplates. AWS guarantees the same accuracy as an exhaustive search with template matching. In AWS preprocessing, a reference subtemplate is selected from the set of subtemplates. The position of the reference subtemplate affects the computational cost. But this position has not been taken into account in AWS. In this paper, we propose a new method which takes into account the position of reference subtemplate. Experimental results show that the proposed method is faster than AWS.

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We propose a novel approach for the photon shot noise reduction in image sensors inspired from an M-transform method. In our proposed method, the photon shot noise is transfered to small amplitude random signals. Then the small amplitude random signals are removed by the ε filter. The Sobel method was used for the edge detection and the edge was preserved by not applying the ε filter into the edge. After the noise reduction, the signals are restored to the image by a reverse M-transform. We compared our method with the smoothing filter, the median filter and the Wiener filter. In the photon shot noise according to the Poisson distribution, we changed the incidence number of photons and created the noise image by the simulation. In cases where the number of the maximum incidence photons was 128 pieces (illumination of about 2 lux), the proposal technique indicated the PSNR (Peak-Signal to Noise Ratio) value better than the Wiener filter. Furthermore, the proposal technique confirmed better than the smoothing filter subjectively according to the effect of edge preservation also under dark environment. As the result, our method is confirmed effective for the photon shot noise reduction.

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By the word “Personal vehicle”, we mean a simple and lightweight vehicle expected to emerge as personal ground transportation devices. The motorcycle, electric wheelchair, motor-powered bicycle, etc. are examples of the personal vehicle and have been developed as the useful for transportation for a personal use. Recently, a new types of intelligent personal vehicle called the Segway has been developed which is controlled and stabilized by using on-board intelligent multiple sensors.
The demand for needs for such personal vehicles are increasing, 1) to enhance human mobility, 2) to support mobility for elderly person, 3) reduction of environmental burdens. Since rapidly growing personal vehicles' market, a number of accidents caused by human error is also increasing. The accidents are caused by it's drive ability. To enhance or support drive ability as well as to prevent accidents, intelligent assistance is necessary. One of most important elemental functions for personal vehicle is robust lane detection.
In this paper, we develop a robust lane detection method for personal vehicle at outdoor environments. The proposed lane detection method employing a 360 degree omni directional camera and unique robust image processing algorithm. In order to detect lanes, combination of template matching technique and Hough transform are employed. The validity of proposed lane detection algorithm is confirmed by actual developed vehicle at various type of sunshined outdoor conditions.

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Flexible Job-shop Scheduling Problem is expansion of the traditional Job-shop Scheduling Problem that an operation can be processed one or more machines. The purpose of this problem is to look for the smallest makespan. For that purpose, it is necessary to decide optimal assignment of machines to operations and order of operations on machines. In this paper, we focus on maximum of workloads for all machines and propose new suvival selection, creation method of initial solution, mutation, and escape method to Genetic Algorithm for this problem. The efficacy of our method is demonstrated by comparing its numerical experiment results with another methods.

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An example-based classification algorithm for pedestrian Detection is presented. The classifier integrates component-based classifiers according to the AdaBoost algorithm. A probability estimate by a kernel-SVM is used for the outputs of base learners, which are independently trained for local features. The base learners are determined by selecting the optimal local feature according to sample weights determined by the boosting algorithm with cross-validation. Our method was applied to the MIT CBCL pedestrian image database, and 54 sub-regions were extracted from each image as local features. The experimental results showed a good classification ratio for unlearned samples.

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Until now, many researchers have proposed spatial relations between geographical objects in the field of geographical information systems and spatial databases. However, these proposals have focused on binary relations to represent the features of geographical objects, but have not concentrated on the complexity among geographical objects. In this paper, we aim to model the complex structure among geographical objects. To represent the structure among geographical objects, we define the geometric spatial relation which is composed of an overlapping relation, an adjoining relation, and a neighboring relation. Additionally, we discuss a retrieval function which finds out similar locations by using a sketch as a query. In order to find out locations, we generate a graph structure for representing the relationships among geographical objects using the three relations. We find a similar structure by comparing two graph structures. To decide a similar structure, we define the similarity which is calculated by correspondence among relations. The correspondence among relations is the value which shows the difference between a query and data. By using this similarity, we can find not only sub-graphs but also similarity graphs.

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In recent years, DoS (Denial of Service) attack and more powerful DDoS (Distributed DoS) attack pose security problems on the Internet. As the measure to these attacks, it is important to trace attackers and stop the attacks. However, since information of the attacker is “spoofed”, it is difficult to trace. Therefore, the method of specifying attackers is required. Savage et al. proposed a method to trace flooding attacks by “marked” packets. This method, however, has some problems gathering the attack packets through a lot of hops. In this paper, we propose a method to solve this problem by observing the feature of attack traffic and change the “marking probability” of the routers. We implement algorithms both of our proposed method and extending marking method to estimate the efficiency of them. From the results of some experiments, we will conclude the effectiveness of our proposed scheme.

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In order to visualize keyword trends embedded in newspaper articles, this paper proposes FACT-Graph (Frequency and Co-occurrence-based Trend Graph). Firstly, we introduce a trend analytical method that works by keywords class. We identify four classes of keywords by TF (Term Frequency) values and DF (Document Frequency) values in an analytical period, and then some keywords are classified into different classes by period. We pay attention to such class transition between periods and make it a clue of trend analysis. Next, we apply a method of identifying relationship between multiple words by their co-occurrence and their transition to resolve problems which occurs in prior class transition analysis. Finally, we output FACT-Graph by extending the traditional simple co-occurrence graph, which visualizes trend analysis and simultaneously examine keyword class and keyword co-occurrence relationship. FACT-Graph is based four classes of keyword, keywords co-occurrence and their transition between time periods. While each class is characterized by shapes of nodes and keywords co-occurrences relationships are represented by the types of lines, the trend transition patterns are colored. Applying the proposed FACT-Graph to the dataset of 220,000 newspaper articles, this paper exemplifies some example result and validates effective in visualizing keyword trends embedded in volumes of text.

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In this paper, grid-connected of the wind power generator was evaluated from viewpoint of the frequency fluctuation. The wind power generation system is the power generation method that depends on natural energy. Therefore, it is feared to exert a bad influence for the electric power quality. As a result, it is necessary to maintain a high electric power quality to do wind power generation in grid-connected.
AC link method,AC-DC link method, and DC link method are enumerated by grid-connected of the wind power generator. The model system was constructed with the use of synchronous generator and induction generator as wind power generator, and the verification experiment was done. The verification experiments that use various grid-connected methods in each generator were conducted. As a result, the steadiest frequency characteristic was obtained in the DC link method. The result in which the stability level is especially the highest in the wind power generation system that adopted DC link method that used wound-rotor induction generator was obtained. Generally, induction generator have grid-connect by AC link method. Therefore, the effectiveness of grid-connected method of induction generator by DC link method could be proven when evaluating it from viewpoint of the frequency fluctuation.

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We propose a multilayer bandpass filter(BPF) with attenuation poles using folded resonators with open-circuited end. Firstly, the basic characteristics of a folded resonator with open-circuited end under the change of the parameters is examined by an electromagnetic simulator. Secondly, 3-pole multilayer BPFs using the resonators above are proposed, simulated and experimented. As a result, the bandpass characteristics with attenuation poles near the lower and higher side of the center frequency is realized by the proposed structure.

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This paper describes a preamplifier circuit of four inputs for full differential voltage comparator, which can compare directly the differential input signal voltage with the differential referential voltage. The problem of a preamp circuit is to occur kickback noise from output terminals to referential terminals through parasitic capacitance of MOS transistors. To suppress the kickback noise, we propose the full differential preamplifier circuit with the current mirror loads. The proposed circuit reduces the kickback noise to 1/10 to compare with a conventional full differential preamplifier circuit.

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This paper proposes a non-contacting certification system by using morphological analysis of contiguous hand images to access security control. The non-contacting hand image certification system is more effective than contacting system where psychological resistance and conformability are required. The morphology is applied to get useful individual characteristic even if the pose of a hand is changed. The experimental results show the more accuracy to certificate individuals was obtained by using contiguous frames compared to conventional method.

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This paper proposes a particle swarm optimization (PSO) with hierarchical structure. In the proposed method, particles are separated into some groups, and besides, in a group particles are parted the particle of the best value from other particles. Particles of the best value in each group are applied to Gbest-Model, and other particles are applied to Lbest-Model. Then, the proposed method is validated through numerical simulations with several functions which are well known as optimization benchmark problems comparing to the conventional PSO methods.

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