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Showing papers by "Waseda University published in 1989"


Journal ArticleDOI
TL;DR: The results for the 1986 survey are compared in this paper, showing that the Japanese are clearly ahead in the trade-off between flexibility and cost efficiency, while the European and North Americans are not yet seizing the opportunity to cut costs through rapid production and design changes, and are focusing more on traditional cost reduction programmes and the improvement of quality.
Abstract: Over the past 4 years research teams from INSEAD (Fontainebleau), Boston University and Waseda University (Tokyo) have administered a yearly survey on the manufacturing strategy of the large manufacturers of the three industrialized regions of the world In this paper the results for the 1986 survey are compared One of the most striking results of that year's survey is the emphasis some of the more advanced manufacturers put on their efforts to overcome the trade-off between flexibility and cost efficiency In particular for the Japanese respondents these attempts become clear Europeans and North Americans are not yet seizing the opportunity to cut costs through rapid production and design changes, and are focusing more on traditional cost reduction programmes and the improvement of quality This might mean that they are preparing the basis on which they can built to obtain added value from flexible automation If this is the case then the Japanese are clearly ahead

464 citations


Proceedings ArticleDOI
01 Jan 1989
TL;DR: In this paper, a generalization of the definition of zeta function is presented, and the computation of Zx(u) for some well known families of graphs is discussed.
Abstract: Publisher Summary This chapter focuses on zeta functions of finite graphs and representations of p-adic groups. It discusses two different subjects: first is a combinatorial problem in algebraic graph theory, and the other is arithmetic of discrete subgroups of p-adic groups and their representations. The chapter presents the notation and basic definitions in graph theory. It also presents a generalization of the definition of zeta function. Spectrum of a finite multigraph is analyzed in the chapter. Moreover, the chapter also describes harmonic functions and the Hodge decomposition. The chapter also presents the computation of zeta functions Zx(u) for some well known families of graphs. These computations give many examples of graphs that are not Ramanujan graphs.

395 citations


Journal ArticleDOI
TL;DR: Observation of the decay lifetime of photoluminescence and calculations using the ab initio molecular-orbital program show that the 7.6-eV band is caused by a singlet-to-singlet transition, while the 5.0-ev band is cause by a singslet- to-triplet transition.
Abstract: Various uv and vacuum-uv optical-absorption bands found in as-manufactured high-purity ${\mathrm{SiO}}_{2}$ glass were studied. Two types of absorption bands were found near 5.0 eV, one of which is attributed to the oxygen vacancy (?Si-Si?). The absorption band at 7.6 eV is also found to be caused by the same oxygen vacancy. Observation of the decay lifetime of photoluminescence and calculations using the ab initio molecular-orbital program show that the 7.6-eV band is caused by a singlet-to-singlet transition, while the 5.0-eV band is caused by a singlet-to-triplet transition.

262 citations




Journal ArticleDOI
TL;DR: In this article, the authors investigated the nature of excess oxygen in as-manufactured and γ-irradiated high-purity synthetic silicas and found that the excess oxygen exists in the glass in two forms: as peroxy linkages and as interstitial molecular oxygen.
Abstract: The nature of excess oxygen in as‐manufactured and γ‐irradiated high‐purity synthetic silicas is investigated. Electron‐spin‐resonance measurements suggest that peroxy radicals ( 3/4 SiOO⋅) could be produced either by the cleavage of peroxy linkages ( 3/4 SiOOSi 3/4 ) or by the reaction of E’centers ( 3/4 Si⋅) with oxygen molecules. The excess oxygen is found to exist in the glass in two forms: as peroxy linkages and as interstitial molecular oxygen. The peroxy linkage is shown to be the cause of optical absorption at 3.8 eV. Heat treatment at 900–1000 °C results in the growth of the 3.8‐eV band, that is, the peroxy linkages, through the reaction of oxygen vacancies and interstitial dioxygen molecules. These results indicate that the 5.0‐ and 3.8‐eV bands (which are characteristic of ‘‘oxygen‐deficient’’ and ‘‘oxygen‐surplus’’ silica, respectively) can coexist in a glass, depending on the synthesis conditions.

117 citations


Journal ArticleDOI
TL;DR: In this article, le cinetique et les constantes d'equilibre for le transfert d'azote a travers des membranes constituees par un copolymere de methacrylate d'octyle and d'un complexe de manganese sont determinees.
Abstract: La cinetique et les constantes d'equilibre pour le transfert d'azote a travers des membranes constituees par un copolymere de methacrylate d'octyle et d'un complexe de manganese sont determinees

91 citations


Journal ArticleDOI
TL;DR: A way to grasp the spatial information of sound fields from impulse responses measured at closely located four points, the origin and three points of the same distance from the origin on the rectangular coordinate axes is discussed.
Abstract: When we estimate a sound field in a room, it is important to grasp the spatial informa-tion, especially of the early reflection periods. In this paper we'll discuss a way to grasp the spatial information of sound fields from impulse responses measured at closely located four points, the origin and three points of the same distance (3∼5cm) from the origin on the rectangular coordinate axes. From these four impulse responses the coordinates and powers of virtual image sources are calculated by correlation technique or intensity technique. Concert halls, opera theaters and many other sound fields are measured by this technique. The distributions of virtual image sources and directivity patterns of some concert halls are shown.

78 citations


Journal ArticleDOI
TL;DR: Magnetic and magnetoelectric measurements were made on a single crystal of ferroelectric PbFe0.5Nb0.3 in this paper, and it was revealed that the magnetic class below and above T m c was determined to be m' and ml', respectively.
Abstract: Magnetic and magnetoelectric measurements were made on a single crystal of ferroelectric PbFe0.5Nb0.5O3. It was revealed that PbFe0.5Nb0.5O3 has a weak ferromagnetic moment and linear magnetoelectric effect below a transition point T m c of approximately 9 K. The magnetic class below and above T m c was determined to be m' and ml', respectively. A possible model of the transition which explains this symmetry change is proposed.

69 citations




Book ChapterDOI
Atsuo Takanishi1, M. Tochizawa1, T. Takeya1, H. Karaki1, Ichiro Kato1 
01 Jan 1989
TL;DR: In 1984, the authors succeeded in attaining dynamic walking on a flat floor using a biped walking robot, WL-10RD, and accomplished the ascending and descending of stairs and slight inclines using the same robot.
Abstract: In 1984, the authors succeeded in attaining dynamic walking on a flat floor using a biped walking robot, WL-10RD. The walking lasted 1.3[sec] with a 0.4[m] step. Moreover, in 1985, the authors accomplished the ascending and descending of stairs and slight inclines using the same robot.

Journal ArticleDOI
TL;DR: It is strongly suggested that rdgA gene correlates closely with DG kinase activity, and the defect of DG Kinase activity is a primary cause of retinal degeneration in rdGA mutant.

Journal ArticleDOI
TL;DR: In this article, the envelope equation was generalized to analyze a resonance among multiple modes by using the method of multiple scales, an excellent method for analyzing large-scale nonlinear systems and demonstrated through numerical simulations that the generalized envelope equation is valid for predicting the resonance phenomena themselves and also for examining the critical factors responsible for severe resonances.
Abstract: The envelope equation derived earlier is generalized to analyze a resonance among multiple modes by using the method of multiple scales, an excellent method for analyzing large-scale nonlinear systems. It is demonstrated through numerical simulations that the generalized envelope equation is valid for predicting the resonance phenomena themselves and also for examining the critical factors responsible for severe resonances. The factors chosen for study are the heaviness of the load, small dampings, and disturbances. The method is promising for the analysis of general multimode resonances. >

Journal ArticleDOI
TL;DR: Montmorillonite-acrylamide intercalation compounds were prepared by treating sodium montmorillonites with acrylamides aqueous solutions, the concentrations of which were varied from 4% to 20% as mentioned in this paper.
Abstract: Montmorillonite-acrylamide intercalation compounds were prepared by treating sodium montmorillonite with acrylamide aqueous solutions, the concentrations of which were varied from 4% to 20%. The basal spacings of the compounds prepared from 4% and 20% acrylamide aqueous solutions were ca. 15 A and 20 A, respectively. These values suggested that acrylamide was intercalated as monomolecular and bimolecular arrangements in the interlayer space of montmorillonite with the molecular plane perpendicular to the silicate sheet. After the removal of excess acrylamide by washing with nonpolar organic solvents, the intercalated acrylamide was polymerized to form montmorillonite-polyacrylamide intercalation compounds. These compounds absorbed more water than raw sodium montmorillonite.

Journal ArticleDOI
TL;DR: In this article, the authors provide a game-theoretic interpretation of the central controller, which plays a central role in characterizing all controllers achieving disturbance attenuation in the sense of the H ∞ -norm in the imperfect observation case.

Journal ArticleDOI
TL;DR: A new hierarchical computing scheme is developed by carefully considering mismatches arising from the system decomposition by making use of an extension of a fast second-order load-flow method which allows to employ a fixed Jacobian matrix in the hierarchical algorithm.
Abstract: Hierarchical computing methods for large-scale Power System State Estimation (PSSE) has gained considerable interest over the last few years. So far, however, no method has been developed that is both practical and optimizes the total system's cost function. The Newton-Raphson method for PSSE has the drawback that the Jacobian matrix is evaluated at each iteration and, each time, must be sent to all the other computers in the hierarchical system. In this paper a new hierarchical computing scheme is developed by carefully considering mismatches arising from the system decomposition. The proposed method makes use of an extension of a fast second-order load-flow method which allows to employ a fixed Jacobian matrix in the hierarchical algorithm. In the problem formulation the power network is decomposed into two or more subsystems; the interaction among the systems is taken into account through the tie-line bus voltages. The hierarchical structure of the proposed method consists of two levels: the upper level, where the optimal tie-line bus voltages are evaluated; and the lower level, where the optimal states of each subsystem are determined by minimizing a cost function that involves the entire system. Three test cases of the proposed method are reported in the paper;more » the test results are compared with those obtained by another hierarchical PSSE method.« less

Journal ArticleDOI
TL;DR: In this paper, the authors discuss le probleme aux valeurs limites et initiales: iu t -Δu+f(|u| 2 )u=0, x∈Ω, t>0, u(x,0)=u 0 (x), x ∈ Ω, u/ ∂Ω =0 t > 0, ou Ω est un domaine borne de R 2 a frontiere lisse ∂ Ω
Abstract: On considere le probleme aux valeurs limites et initiales: iu t -Δu+f(|u| 2 )u=0, x∈Ω, t>0, u(x,0)=u 0 (x), x∈Ω, u/ ∂Ω =0 t>0, ou Ω est un domaine borne de R 2 a frontiere lisse ∂Ω

Journal ArticleDOI
TL;DR: In this paper, the natural and Marangoni convections formed spontaneously in the melt inside a two-dimensional rectangular open boat were investigated by means of an order-of-magnitude evaluation and a numerical analysis according to the finite difference method.
Abstract: The natural and Marangoni convections formed spontaneously in the melt inside a two-dimensional rectangular open boat were investigated by means of an order-of-magnitude evaluation and a numerical analysis according to the finite difference method. A quantitative evaluation was made of the Grashof number, Marangoni number, Prandtl number and melt depth, all of which affect the interfacial velocity and the velocity distribution of the melt convection. It was concluded that Marangoni convection as well as natural convection is important when the melt is shallow.

Journal ArticleDOI
TL;DR: In this article, the Gelfand-Zetlin basis of Uq(gl(N+1)) modules is constructed via the lowering operator method, which is a modification of the lower-operator method.
Abstract: The Gelfand-Zetlin basis of Uq(gl(N+1)) modules is constructed via the lowering operator method.

Journal ArticleDOI
TL;DR: In this article, a two-dimensional position sensitive silicon detector (PSSD) with a good linear response, consisting of a square ion-implanted resistive anode with a boundary of an additional resistive-strip electrode, was newly developed.
Abstract: A two-dimensional position sensitive silicon detector (PSSD) with a good linear response, consisting of a square ion-implanted resistive anode with a boundary of an additional resistive-strip electrode, was newly developed. Linearity and resolution for the PSSD were investigated using 40 MeV helium and 95 MeV nitrogen ion beams. The PSSD has an effective area of 45 mm×45 mm, a thickness of 400 μm, a junction capacitance of 500 pF, a surface resistance of the ion-implanted resistive anode of 18 kω□ and a resistance of the strip line of 1.4 kω. The nonlinearities and resolutions (FWHM) of the position were 0.75% and 1.97 mm for 40 MeV helium ions obtained by 6 μs pulse shaping, and 0.47% and 0.71 mm for 95 MeV nitrogen ions obtained by 12 μs pulse shaping, respectively.

Journal ArticleDOI
TL;DR: In this article, the surface structures of Si(100)-Al phases of coverages less than one monolayer were studied by low energy electron diffraction (LEED) and Auger electron spectroscopy (AES).

Journal ArticleDOI
Abstract: The first 500-kV long-distance cable line is described. This oil filled self-contained cable has been installed along the Seto-Ohashi bridge connecting Shikoku, the fourth largest of the four major islands that constitute Japan with Honshu, the main island. The power flow will generally be from Shikoku where there is a surplus of power to Honshu, the main island. The technical features of the cable and its installation are described. Polypropylene laminated paper (PPLP), a low-loss insulation paper with high dielectric performance, was adopted, allowing the cable to carry the required transmission capacity of 1200 MW per circuit without forced cooling. The number of splices is also reduced by approximately 40%, resulting in further economy. >


Journal ArticleDOI
TL;DR: Three test cases using the hierarchical computing scheme for power system state estimation made use of an extension of a fast second-order load-flow method that allows a fixed Jacobian matrix to be used in the hierarchical algorithm are reported here.
Abstract: A hierarchical computing scheme for power system state estimation is developed by carefully considering mismatches arising from the system decomposition. The method makes use of an extension of a fast second-order load-flow method that allows a fixed Jacobian matrix to be used in the hierarchical algorithm. In the problem formulation, the power network is decomposed into two or more subsystems; the interaction among them is taken into account through the tie-line bus voltages. The hierarchical structure of the method consists of two levels: the upper level, where the optimal tie-line bus voltages are evaluated; and the lower level, where the optimal states of each subsystem are determined by minimizing a cost function that involves the entire system. Three test cases using the method are reported here and the test results are compared with those obtained by another hierarchical power system state estimation method. >

Journal ArticleDOI
TL;DR: Preparation du PPS par polymerisation du thiophenol ou du disulfure de diphenyle catalysee par VO (acac) 2 en presence d'un acide fort, via la formation d''un sel de phenyl bis-phenylthiosulfonium as discussed by the authors.
Abstract: Preparation du PPS par polymerisation du thiophenol ou du disulfure de diphenyle catalysee par VO (acac) 2 en presence d'un acide fort, via la formation d'un sel de phenyl bis-phenylthiosulfonium

Journal ArticleDOI
TL;DR: It is shown that the kernel can stabilize the solution of the Langevin equation and this scheme is applied to Minkowski stochastic quantization and the numerical simulation of simple polynomial models.

Journal ArticleDOI
TL;DR: In this article, a kaolinite-pyridine intercalation compound was prepared using hydrated hydrated kolinite as an intermediate, which showed the presence of hydrogen bonding between the hydroxyls of the pyridine.
Abstract: A kaolinite-pyridine intercalation compound was prepared using hydrated kaolinite as an intermediate. Hydrated kaolinite having a basal spacing of l0/~ was treated with pyridine to form a well- ordered intercalation compound having a basal spacing of 12.0/k. Infrared spectroscopy indicated the presence of hydrogen bonding between the hydroxyls of the kaolinite and the pyridine. 29Si nuclear magnetic resonance spectroscopy with cross polarization and magic-angle spinning revealed that inter- calated pyridine affected the environment of silicon. The mono-substituted pyridine derivatives were also intercalated with hydrated kaolinite. On the basis of the basal spacings of the intercalation compounds and the stabilities of the derivatives between the layers, the pyridine appeared to be in an approximately perpendicular position, with the nitrogen facing the gibbsitic sheets.

Journal ArticleDOI
TL;DR: In this paper, Bilinear residue formulas for the super-KP hierarchy and the ortho-symplectic super-kP hierarchy were established for the first time.
Abstract: Bilinear residue formulas are established for the super-KP hierarchy and the ortho-symplectic super-KP hierarchy. Furthermore, superframes corresponding to the ortho-symplectic super-KP hierarchy are completely characterized. Soliton solutions to the super-KP hierarchy are given.

Journal ArticleDOI
TL;DR: The device for continuous measurement of SIPA is an important new tool to study one aspect of platelet functions and a good correlation between platelet count and transmitted light intensity under the conditions in which no activation of platelets occurred.