We describe several classes of Montesinos links up to mutation and 5-move equivalence, and obtain from this a Jones and Kauffman polynomial test for a Montesinos link.

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For motion planning of a manipurator, the use of a configuration space is highly efficient. Algorithms of the collision-free planning in static environments have been proposed in many papers. The efficiency of the algorithms depends on the description of obstacles in a configuration space. In general, the complexity of a configuration space map exponentially increases with the number of joints. Therefore, building the configuration space map is a time-consuming process, and the collision-free path can not be searched in real time. In this paper, we illustrate mathematical properties of a new kind of configuration space and propose an approach to parameterizing an obstacle in the configuration space. A spherical obstacle in a work space is transformed into a characteristic subspace in the configuration space. Therefore, we can approximate parameters of a sphere as a set of geometric entities. The transformation of a complex work space into the configuration space is described in terms of integrating the transformation of each element of a set of spheres. A collision-free path in a dynamic environment is found by using a Penalty-Function-Method. The Penalty-Function is modified according to the factors of the velocity along axes in a polar coordinates system.

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The competitiveness of Japan's semiconductor industry fell sharply in the latter half of the 1990s. This paper attempts to explore structural factors behind this by focusing particularly on production systems. In doing so, special attention is paid to the rapid increase in complexity of technologies and markets, a phenomenon brought about by the “self-propagating” evolution of information technologies of the semiconductor industry's own making. Such an increase in complexity calls for highly specialized knowledge⁄know-how. At the same time, it is necessary to create a mechanism for combining such knowledge⁄know-how so as to ensure its cumulative and agile generation in an integral form. Japan's semiconductor industry, however, has yet to create such a mechanism for its production system. This paper attempts to identify factors behind this and find clues toward solving the problem.

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In this study, indium tin oxide (ITO) and indium zinc oxide (IZO) films were deposited on quartz glass through alternating sputtering. The optical and electrical properties of these films were characterized through spectroscopic ellipsometry (SE). The optical constants of ITO and IZO films were accurately estimated using a model that combined the Tauc–Lorentz, Gauss, and Drude models. However, the estimated resistivity was close to the Hall measurements only when the film thickness was higher than 250 nm. Anisotropy caused by the preferential orientation of crystallites increased the difficulty of the SE fitting process. Furthermore, a k-factor defined on the basis of the estimated optical constants was used to examine the Zn content of the IZO films. Variation in the k-factor was consistent with the band gap of the IZO films.

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In former studies for the cusps on coupler curves, only the number of cusps for some special types of six-link mechanisms was obtained, and mechanisms having cusps have not yet been synthesized. In the present paper, the Stephenson-I mechanism among three types of six-link path-generators is described. First the types of cusps are classified, and the number and positions of them are defined. Then considering the four- and degenerated six-link mechanisms which are equivalent to general six-link ones in the neighbourhoods of cusps, the inclinations of tangents at cusps are obtained. Further, a new method for expressing the error between the ideal and generated curves is suggested, and as a result, the synthesis of a six-link mechanism is carried out such as to satisfy the number and positions of cusps, the inclinations of tangents at cusps, and the shape of the ideal curve.

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Contributions of the receptor and basolateral membranes to the resting potential in bullfrog taste cells were studied by replacing the superficial and interstitial fluids of the tongue by various salines. When the interstitial K⁺ concentration ([K⁺]₀) was increased to 100mM, the resting potential decreased by 45%. A similar increase in superficial [K⁺]₀ decreased the resting potential by 15%. A simultaneous increase in both superficial and interstitial [K⁺]₀ to 100mM decreased the resting potential by 60%. Total removal of Na⁺ from either the superficial or interstitial fluid increased the resting potential by 40%. Ouabain (10^-4M) in the interstitial fluid decreased the resting potential by 30%, while the drug in the superficial fluid had no effect. Amiloride (10^-3M) in the superficial fluid hyperpolarized the cells to 145%, while the drug in the interstitial fluid caused no change in the resting potential. Ca²⁺ -free superficial saline reduced the resting potential to 75%. Interstitial Ca²⁺ did not affect the resting potential. Total removal of either superficial Cl^- or interstitial Cl^- did not change the resting potential. These results suggest: 1) Na⁺ and + across the receptor and basolateral membranes of the taste cell down their electrochemical gradients, 2) Na⁺ is extruded from the taste cell by the Na-K pump which exists only in the basolateral membrane, 3) the resting potential of a frog taste cell consists of the diffusion potentials of Na⁺ and K⁺ across the receptor and basolateral membranes, and the potential resulting from the activity of the electrogenic Na-K pump in the basolateral membrane.

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Phospholipases are a class of ubiquitous enzymes and ditected either intracellularly or intercellularly over a wide variety of organisms. The functions of phospholipases are diverse: 1, The action of phospholipases in digestion (digestion of extracellular phospholipids in phagocytes and digestion of dietary phospholipids in the intestine), 2, Regulatory phospholipases. Some phospholipases may play an important role in the transmembrane control and also in the generation of bio-active lipids such as icosanoids and PAF, both of which may function as a mediator of various cell-cell communications. 3, Detoxication. 4, Remodeling of membrane phospholipids.
The functional and structural aspects of various phospholipases will be reviewed in this article.

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In this paper, we report on an application of tabu search to the graph partitioning problem which has applications on circuit board wiring and program segmentation. We discuss how to adapt tabu search to the graph partitioning problem and compare the performance with simulated annealing, another variant of local search incorporating randomized technique. Numerical experiments show that our algorithm dominates the simulated annealing algorithm in accuracy of solutions and speed on both uniform and geometric instances. In particular, our tabu search implementation works much better than the simulated annealing algorithm on structured (geometric) instances. We also investigate how to tune up our implementation and to optimize the various parameters via extensive numerical experiments.

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A synchrotron radiation white X-ray diffraction of a Heusler-type Ni_2.18Mn_0.82Ga single crystal was observed by changing the temperature from 400 to 103 K. To investigate precisely the process of the martensitic transformation, changes in Laue spots during the transformation process were observed. The following phenomena were discovered: The single crystal at 300 K before increasing temperature shows a tetragonal structure, the a- or b-axis of which is parallel to the direction of crystal growth. It shows a cubic Heusler structure at 400 K after heating. One of the cubic axes is parallel to the direction of crystal growth. With decreasing temperature, the crystal transforms into many small variants with tetragonal structures. One of the variants evolves so that the a- or b-axis is parallel to the direction of the crystal growth, and the orientation of the other variants can be represented by its rotation about the cubic ⟨111⟩ axis. The rotation angle is at most a few degrees, which changes gradually with decreasing temperature. At 103 K the transformation is almost complete and many tetragonal variants are rearranged into one tetragonal structure, the a- or b-axis of which is parallel to the direction of crystal growth.

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This paper proposes a low-complexity algorithm to calculate log likelihood ratios (LLRs) of coded bits, which is necessary for channel decoding in coded MIMO mobile communications. An approximate LLR needs to find a pair of transmitted signal candidates that can maximize the log likelihood function under a constraint that a coded bit is equal to either one or zero. The proposed algorithm can find such a pair simultaneously, whereas conventional ones find them individually. Specifically, the proposed method searches for such candidates in directions of the noise enhancement using the MMSE detection as a starting point. First, an inverse matrix which the MMSE weight matrix includes is obtained and then the power method derives eigenvectors of the inverse matrix as the directions of the noise enhancement. With some eigenvectors, one-dimensional search and hard decision are performed. From the resultant signals, the transmitted signal candidates to be required are selected on the basis of the log likelihood function. Computer simulations with 4×4 MIMO-OFDM, 16QAM, and convolutional codes (rate =1/2,2/3) demonstrate that the proposed algorithm requires only 1.0dB more E_b/N₀ than that of the maximum likelihood detection (MLD) in order to achieve packet error rate of 10^-3, while reducing the complexity to about 0.2% of that of MLD.

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In order to satisfy the transportation demand for elderly and disabled people, providing efficient dial-a-ride systems is an important issue. Appropriate vehicle routes for dial-a-ride systems can increase transportation efficiency and reduce the operation cost. Most literatures focus on improving the vehicle routing and scheduling and assume that the travel time is a constant value. However, the travel time can fluctuate dramatically due to traffic congestion or incident. Using the constant travel time to solve dial-a-ride problems (DARP) cannot obtain the efficient vehicle routes. To consider the variation of the travel time, this paper formulates a mixed integer programming formulation for the time-dependent DARP with time window. In the formulation, the travel time variations are treated as step functions. The simulation-assignment model, DynaTAIWAN is applied to generate time-dependent travel time matrices and simulate traffic flows in the real network. Numerical experiments are conducted in a Kaohsiung network.

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In order to satisfy the transportation demand for elderly and disabled people, providing efficient dial-a -ride systems is an important issue. Appropriate vehicle routes for dial-a-ride systems can increase transportation efficiency and reduce the operation cost. Most literatures focus on improving the vehicle routing and scheduling and assume that the travel time is a constant value. However, the travel time can fluctuate dramatically due to traffic congestion or incident. Using the constant travel time to solve dial-a-ride problems (DARP) cannot obtain the efficient vehicle routes. To consider the variation of the travel time, this paper formulates a mixed integer programming formulation for the time-dependent DARP with time window. The simulation-assignment model, DynaTAIWAN is applied to generate time-dependent travel time matrices and simulate traffic flows in the real network. Numerical experiments are conducted in a Kaohsiung network.

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Physical-layer network coding with binary turbo coding in a two-way relay channel is considered. A two-user turbo decoding scheme is proposed with a simplified sum trellis. For two-user iterative decoding at a relay, the component decoder with its simplified sum trellis decodes the superimposed signal to the arithmetic sum of two users' messages. The simplified sum trellis is obtained by removing one of the states in a pair of mutual symmetrical states from a sum trellis. This removal reduces the decoding complexity to half of that with the sum trellis, and does not degrade decoding performance over AWGN channel since two output sequences from the pair of mutual symmetrical states are the same.

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Application of high-carbon metallic briquette (HCMB) in the blast furnace (BF) ironmaking for coke saving was previously proposed. This paper is focused on clarifying the in-furnace phenomena and demonstrating the advantages of applying the HCMB in BF ironmaking. A mathematical model has been formulated based on the gas-solid counterflow and its validity was confirmed by the comparison of the simulation results with the averaged industrial data from a BF with a productivity of 6250 tHM/day. Afterward, BF operations under two HCMB mixing ratios (5% and 10%) were simulated. Simulation results indicate that charging HCMB in BF can suppress the coke gasification and improve the ore reduction above the CZ. Coke of approximately 12 kg could be saved for producing one-ton hot metal from the ore under an HCMB mixing ratio of 5%, and approximately 17 kg under an HCMB mixing ratio of 10%. Simulation results still indicate that the reasonable mixing ratio of HCMB is less than 5%, under which, significant changes of the BF operation conditions for HCMB charging are not required.

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It is known that principal orbits of Hermann actions on a symmetric space of non-compact type are curvature-adapted isoparametric submanifolds having no focal point of non-Euclidean type on the ideal boundary of the ambient symmetric space. In this paper, we investigate the mean curvature flows for such a curvature-adapted isoparametric submanifold and its focal submanifold. Concretely the investigation is performed by investigating the mean curvature flows for the lift of the submanifold to an infinite dimensional pseudo-Hilbert space through a pseudo-Riemannian submersion.

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