Showing papers by "Harbin Institute of Technology published in 1989"
TL;DR: In this paper, a lower bound approach is proposed for the first time to solve the macroscopic yield loci of porous materials, which is shown to be much more in accordance with the experimental results than the Gurson's.
Abstract: A lower bound approach is proposed for the first time to solve the macroscopic yield loci of porous materials. The results are then compared with Gurson's upper bound yield loci and those of the experiments. It is shown that the present analysis is much more in accordance with the experimental results than the Gurson's.
48 citations
TL;DR: In this article, a new technology in the field of manufacturing spherical vessels has been developed, the distinguishing feature of which is that the sheet blank is cut into simple polygons which are then welded into a polyhedral shell, by pressurising the shell hydraulically, the polyhedron is gradually expanded into a spherical vessel; however, certain technical measures need to be taken.
43 citations
TL;DR: Five ternary logic implementations: Complement, Max(x), Min(x, y), Cycle, and Literals, have been demonstrated experimentally and any ternARY logic function can be generated with the light-current mirror and the logic primitives.
Abstract: A design for optoelectronic multiple-value logic circuits that uses bistable laser diodes or light-emitting diodes is reported. In this multiple-valued logic design, an optoelectronic tristable switching circuit, or light-current mirror, in which two bistable light-emitting diodes are connected in parallel serves as the basic logic element. Five ternary logic implementations: Complement, Max(x, y), Min(x, y), Cycle, and Literals, have been demonstrated experimentally. Furthermore, any ternary logic function can be generated with the light-current mirror and the logic primitives.
30 citations
TL;DR: Etude du processus de precipitation de la phase Ti 3 Ni 4 and son influence sur les temperatures de transformation de phase de la matrice dans un alliage Ti-51,8% at. Ni apres vieillissement
26 citations
TL;DR: Etude theorique de la lubrification elastohydrodynamique dans le cas d'un lubrifiant liquide contenant des particules solides in suspension as discussed by the authors.
Abstract: Etude theorique de la lubrification elastohydrodynamique dans le cas d'un lubrifiant liquide contenant des particules solides en suspension
21 citations
TL;DR: In this paper, a group of new equations which can be used to calculate the tilt angle for crystal specimen orientation adjustment in the transmission electron microscope was presented, which avoids the difficulties associated with orientation adjustment of severely strained and small grain size specimens using the Kikuchi map procedure.
17 citations
TL;DR: In this article, an equation has been used to calculate the practical tilt angles of TEM specimens using a double-tilt holder, which is more convenient and less time consuming when compared to other methods.
15 citations
14 citations
01 Nov 1989-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: In this paper, the effect of the morphology and distribution of ferrite, especially acicular ferrite in a Widmanstatten structure, on the fracture behaviour of mild steel at low temperatures is discussed in detail.
Abstract: The effect of the morphology and distribution of ferrite, especially acicular ferrite in a Widmanstatten structure, on the fracture behaviour of mild steel at low temperatures is discussed in detail. The microstructures of polygonal ferrite, intersecting acicular ferrite and parallel acicular ferrite were obtained using an interrupted cooling procedure, and the different effects on the fracture toughness at low temperature were found. If an intersecting acicular ferrite microstructure is present, then the steel has superior toughness at low temperature in comparison with that of polygonal ferrite. If the microstructure is mainly composed of parallel acicular ferrite, however, the steel toughness is comparable to that of polygonal ferrite.
13 citations
TL;DR: In this paper, the surface integrity of bearing steel GCr15 with resin bonded cubic boron-nitride (CBN) wheels was investigated, and two new dressing techniques, elastic dressing and ultrasonic vibration dressing, were used to make the wheels have a strong cutting capacity to obtain higher ground surface integrity.
12 citations
TL;DR: In this article, it is considered that filiform wear products can be formed when the molten asperities of wearing surface come into contact and then move away from each other, followed by rapid cooling.
TL;DR: It is shown that fuzzy Φ-mean convergence is equivalent to convergence in fuzzy measure and LΦ(μ)=L1(μ) for any Orlicz function Φ.
TL;DR: Ion-sensitive field effect transistors (ISFETs) have been successfully introduced into a titration system for flow injection analysis (FIA), with good linearity between teq (titration time) and log C02 (concentration of analysed substance), with a regression coefficient better than 0.9997.
TL;DR: In this article, a modelle de clivage et al. analyse de plusieurs temperatures de transition dans la rupture de l'acier doux and determine a temperature caracteristique for the fragile case.
TL;DR: A general method for the precise evaluation of the integrated effective emissivity of a diffuse frustrum-cone cavity is formulated and can be applied to calculate precisely the integrated emISSivity of, or the irradiance of a detector from, any practical axisymmetric cavity with circular symmetry.
Abstract: A general method for the precise evaluation of the integrated effective emissivity of a diffuse frustrum-cone cavity is formulated. The mathematical expressions derived can be applied to calculate precisely the integrated emissivity of, or the irradiance of a detector from, any practical axisymmetric cavity with circular symmetry. Some typical values of integrated emissivity are presented for cylinders, cylindro-cones, double cones, and cylindro-inner-cones, and comparisons between such cavities are made.
TL;DR: Etablissement d'un modele physique pour decrire le processus de clivage dans un acier bas carbone permettant une meilleure comprehension du parametre qui dicte le comportement de rupture par clivages as mentioned in this paper.
TL;DR: In this paper, the potential of laser plasma soft X-ray sources for scientific and technical applications is briefly reviewed and the influence of different soft Xray spectra on the laser energy has been investigated.
Abstract: Spectra of laser-induced plasmas at low laser energies and intensities (around 100 mJ and 1010 W cm−2 respectively) have been recorded in the spectral range of 20 to 100 nm for different target materials, laser intensities at the target and laser wavelengths. For heavy target materials, a broadband spectrum with a spectral maximum typically around 30 nm is obtained. This broadband radiation source is well suited for photoionization processes and the generation of short wavelength inner-shell photoionization lasers. For the cadmium-photoionization laser, the influence of different soft X-ray spectra on the laser energy has been investigated. The potential of laser plasma soft X-ray sources for scientific and technical applications is briefly reviewed.
TL;DR: This paper presents a new approach, called semi-structured movements, based on the idea of cursor movement paths, or streams, that the cursor can follow in a program, that eliminates the ‘treeness’ of structured movements and the flatness of textual movements, while providing an inherent support for program editing and browsing.
Abstract: It has been recognised that cursor movements on a textual representation of a program present some problems when the movements are based on an underlying abstract syntax tree in a programming system. Approaches taken in many systems are to use structured or textual cursor movements, although both these approaches have some drawbacks. This paper presents a new approach, called semi-structured movements, based on the idea of cursor movement paths, or streams, that the cursor can follow in a program. The key benefits of this approach are that it eliminates the ‘treeness’ of structured movements and the flatness of textual movements, while providing an inherent support for program editing and browsing. Semi-structured cursor movements have been successfully implemented in the MUPE-2 programming environment, and this paper gives several scenarios in order to illustrate example cursor movements.
14 Nov 1989
TL;DR: It is shown that it is possible to process a large segment data in azimuth as to improve resolution and track loss arising from target scintillation or shadowing effect can be greatly reduced.
Abstract: In this paper, a method of precise motion compensation for InverseSynthetic Aperture Radar (ISAR) has been submitted. It is the overall target and not any particular target scatter which is tracked to do the motion compensation. Thus track loss arising from target scintillation or shadowing effect can be greatly reduced. So, it is possible to process a large segment data in azimuth as to improve resolution. The results shown in this paper demonstrate that the method of motion compensation is effective and feasible against maneuvering target.
TL;DR: Based on the hypothesis of linearity of nonlinear machine tool chatter, a new system model of cutting dynamics is presented in this article, which unifies the existing linear chatter theory, the non-linear chatter theory and the mechanism of the restraint of ultrasonic vibration assisted cutting on chatter.
Abstract: Based on the hypothesis of linearity of non-linear machine tool chatter, a new system model of cutting dynamics is presented in this paper, which unifies the existing linear chatter theory, the non-linear chatter theory and the mechanism of the restraint of ultrasonic vibration assisted cutting on chatter.
After introducing the boundary modulation N(s), the transformation function of the new system model is deduced. Then the system model is modified according to the workpiece surface outline. The characteristic equation is deduced from the modified model.
The difference between the boundary modulation frequency and the close-loop mode frequency is analyzed according to the characteristic equation, and our experimental research verifies the analysis.
Ultrasonic vibration assisted cutting is an efficient technology to restrain machine tool chatter. The mechanism of this is that, in ultrasonic vibration assisted cutting, the modulus of the non-linear modulation N(s) is less than 1.00, so that the real cutting stiffness decreases to |N(s)| times that in traditional cutting with the same cutting condition.
01 Jan 1989
TL;DR: In this paper, series solutions to the Navier-Stokes equations are obtained, on the basis of an asymptotic expansion in the radial direction and a new theory of multifold series expansion for the time variable.
Abstract: The present paper concerns the unsteady laminar incompressible flow between two parallel disks with a fluid source at the center of the disk (s). Both the flow rate of the source and the gap width between the disks are varied arbitrarily with time and independently of each other. Such a flow often appears in a nozzle-flapper valve or in a statical pressure bearing such as the piston shoes of a swash type axial piston pump. Series solutions to the Navier-Stokes equations are obtained, on the basis of an asymptotic expansion in the radial direction and a new theory of “multifold series expansion” for the time variable. The solutions describe precisely the non-linear interaction between the two coexisting flows. Experiments were carried out for the case where both the gap width and source flow were varied sinusoidally. The solutions agree well with the experimental results over a wide range of the flow conditions.
01 Jan 1989
TL;DR: In this paper, the sheet blank is cut into simple polygons and then they are welded into a polyhedron shell, by filling the shell with a pumping-force transmission medium, gradually the polyhedral shell will be expanded into a spherical vessel, however certain technical measures are needed to be taken according to a specific loading curve.
Abstract: New Technology in the field of manufacture of spherical vessels has changed the traditional processes for making spherical vessels. The distinguishing feature of this new technology is that the sheet blank is cut into simple polygons and then they are welded into a polyhedron shell. After this, by filling the shell with a pumping-force transmission medium, gradually the polyhedron will be expanded into a spherical vessel, however certain technical measures are needed to be taken according to a specific loading curve. This new technology has novel features. The product has a reasonable structure, artistic appearance and no need for presses and dies. It can be applied to water system, decoration, food chemical industry, oil, metallurgy and atomic industry. The new technology can be used to make spherical vessels of carbon steel, aluminum and stainless steel.
TL;DR: In this paper, some new sufficient conditions for the stability of interval matrices were given by Argoun (1986), however, these conditions are incorrect and are not sufficient for interval matrix stability.
Abstract: Some new sufficient conditions for the stability of interval matrices were given by Argoun (1986). These conditions, however, are incorrect.
TL;DR: In this article, the authors reported the experimental observation of a transitory state during the build-up of photorefractive effects in lithium niobate slab waveguides by prism coupling light into and out of the structure.
TL;DR: Clarification des different processus de rupture and des different facteurs qui les gouvernent a partir des resultats d'essais de traction, de flexion and de choc sur des echantillons de differentes orientations as discussed by the authors.
TL;DR: In this paper, the development of inherent damage near notch tip in 3D carbon-carbon was examined with polariscopic microscope while loading, and a specially designed adjustable stand and loading apparatus were designed and fabricated.
Abstract: First of all, the development of inherent damage near notch tip in 3D carbon-carbon was examined with polariscopic microscope while loading. To track the notch tip during loading, a specially designed adjustable stand and loading apparatus were designed and fabricated. Based on the observation, a very simple analytical model was es tablished. In order to use micromechanics to predict the notched strength, the in-situ strength of fiber bundle was measured with a specially designed fixture. The notched strength of 3D carbon-carbon material was predicted from the longitudinal strength of the portion of the fiber bundle, where the stress concentration takes place. Hedgepeth's stress concentration factor for infinite plate is corrected for finite plate. Calculation of stress fac tors show that failure of a single fiber bundle nearest to the notch tip will cause total failure of the specimen. With Zweben's statistical strength criterion, the strength of the notched 3D carbon-carbon material was predicted and th...
TL;DR: The purpose is to introduce a particular kind of fuzzy topological algebra, viz. fuzzy normed algebras, and to use fuzzy normes to represent locally m -convex fuzzyTopological algebraes.
TL;DR: A new attribute-based Learning algorithm GS, utilizing cycles of generalization and specialization, is introduced, which is simple, efficient and easy to implement.
Abstract: A new attribute-based Learning algorithm GS, utilizing cycles of generalization and specialization, is introduced. GS is simple, efficient and easy to implement. A comparison with existing algorithms AQ11 and ID3 shows that GS has some advantages over them.
TL;DR: In this article, the minimum film thickness and the central film thickness in elastohydrodynamic lubrication (suitable for all regimes) were calculated using two universal formulae, and the limitations and definite applicable ranges of Grubin's formula and Dowson-Toyoda's formula were proposed.
01 Jan 1989
TL;DR: A basic method for the time domainsimulation of fluid transmission lines and a set of rational polynomial approximation sobtained in previous papers is confirmed in time domain for seven unique transfer matrix elements inthe distributed parameter model.
Abstract: A basic method for the time domainsimulation of fluid transmissionlines is introduced in this paper.First of all, accurate approximationare made for propagation operatorr and characteristic impedanceZc in the distributed parametermodel of the lines. Then, the methodof Fast Inversion Laplace Transformis applied to deal with the inversionLaplace transform of the modelwhere propagation operator and characteristicimpedance are replacedby their accurate approximations. Inaddition, by means of the method andcharacteristics method a set ofrational polynomial approximationsobtained in previous papers is confirmedin time domain for sevenunique transfer matrix elements inthe distributed parameter model. Theresearch is meaningful for simulationof hydraulic systems and fluidmeasurement using the dynamic modelof fluid transmission lines.