Showing papers by "Military Academy published in 1998"
TL;DR: A new method for ranking fuzzy numbers by distance method, based on calculating the centroid point, which can rank more than two fuzzy numbers simultaneously, and the fuzzy numbers need not be normal.
772 citations
TL;DR: A general model based on pseudo-arithmetical operations and g -functions will be created and shown to be reasonable only up to an isomorphism of fuzzy partitions.
42 citations
TL;DR: This paper presents a novel motion estimate scheme, called correlation search, which attempts to find the highest motion-correlation neighbor block from the spatial and temporal neighbor blocks.
Abstract: Block-matching motion estimation plays an important role in video coding. In general, there exists a high motion correlation between neighbor blocks in spatial and temporal directions. This paper presents a novel motion estimate scheme, called correlation search, which attempts to find the highest motion-correlation neighbor block from the spatial and temporal neighbor blocks. The motion vector of the highest motion-correlation neighbor block is regarded as the motion estimate of the current block. The correlation search scheme can be based on any existing block matching algorithms. When the scheme is based on a full-search algorithm, it achieves almost the same estimate accuracy with a significant reduction of computational complexity. If the scheme is based on a fast search algorithm, it obtains better estimate accuracy in addition to the improvements in computation.
37 citations
TL;DR: Examined the results of excimer laser phototherapeutic keratectomy combined with simple excision in recurrent pterygium to minimize the recurrence rate and obtain a smooth corneal surface, this procedure seems to be effective and safe.
Abstract: Purpose: To analyze the results of excimer laser phototherapeutic keratectomy (PTK) combined with simple excision in recurrent pterygium to minimize the recurrence rate and obtain a smooth corneal surface. Setting: Veni Vidi Eye Health Centre, Istanbul, Turkey. Methods: Combined pterygium excision and excimer laser PTK was performed in 22 eyes with recurrent pterygium (22 patients). Both spot and scan modes of the Meditec MEL 60 excimer laser were used to produce a wide ablation layer (depth 40 to 80 μm). Results: During the mean follow-up of 16.5 months (range 6 to 27 months), visual acuity, refraction, slitlamp, and corneal topography examinations were recorded. Pterygium recurred in only 1 eye (4.5%). Postoperative visual acuity improved in 15 eyes (68.2%). Keratometric readings were not accurately measured preoperatively because of corneal surface irregularities but could be easily taken after the surgery. Corneal astigmatism ranged from 0 to 2.00 diopters (D) (mean 1.23 D). Three months after surgery, no haze persisted in any eye. No significant intraoperative or postoperative complication was detected. Conclusion: Excimer laser PTK appears to simplify pterygium surgery because a superficial keratectomy is sufficient to remove pterygium. The excimer laser can be used to ablate the visible residual tissues and smooth the corneal surface, resulting in good postoperative refraction and visual acuity. Consequently, this procedure seems to be effective and safe.
35 citations
TL;DR: The results suggest that N- and L-type, but not T- type, voltage-dependent calcium channels are implicated in the spinal processing of nociceptive information.
Abstract: 1. Antinociceptive effects of intrathecally administered aminoglycoside antibiotics, calcium-channel blockers, nickel and calcium ions on the acetic acid–induced writhing test in mice were examined. 2. Neomycin (0.5–20.0 μg/mouse) gentamicin (5–40 μg/mouse), nicardipine, diltiazem and verapamil (0.5–80.0 μg/mouse) and calcium ions (0.02–1.0 μmol/mouse) exerted a dose-dependent antinociceptive activity on the acetic acid–induced writhing test. Nickel ions ( 2.5, 5.0 and 10.0 μmol/mouse) were found ineffective in this test. 3. These results suggest that N- and L-type, but not T-type, voltage-dependent calcium channels are implicated in the spinal processing of nociceptive information.
32 citations
TL;DR: In this paper, a submersible manipulator was used to measure the compressive mechanical properties of polyethylene composites and to model the behavior by finite element analysis. And the fracture strength and the buoyance was obtained.
Abstract: The objective of this work is to manufacture particulate composites, to measure their compressive mechanical properties and to model the behavior by finite element analysis. Syntactic foams, glass bubbles in epoxy resin, have low density and hence are ofparticular interest for subsea applications. The research reported here is undertaken in the context ofa submersible manipulator. In the laboratory two types of specimens are manufactured and tested. including (a) coupons ofthe same particle size with varied particle volume fractions and (b) coupons of the same particle volume fraction with different particle sizes. From the compressive test, we receive the fracture strength and observe the fracture mechanism. Also the buoyance is obtained. In order to correlate the experimental data, the three-dimensional (3-D) finite element method of axis symmetry and cubic center symmetry is used numerically. The predicted values and locations ofthe maximum tensile stresses of specimens agree well with the failure mechanism. It is found that small particles are stronger than matrix, whilst larger particles are weaker than matrix. A decrease in particle volume fraction increases the strength at fixed particle size. An increase in panicle size increases the strength at fixed particle volume fraction.
23 citations
19 citations
TL;DR: In this article, the authors compared substituent effects on reactivity for base hydrolysis of tris-ligand-iron(II) complexes of Schiff base ligands derived from 2-acetylpyridine and substituted benzylamines and their aniline analogues.
Abstract: Substituent effects on reactivity are compared for base hydrolysis of tris-ligand-iron(II) complexes of Schiff base ligands derived from 2–acetylpyridine and substituted benzylamines and their aniline analogues. The methylene spacer in the former effectively isolates the iron from substituent effects in the phenyl ring, as indicated by the almost equal rate constants for base hydrolysis of the complexes derived from benzylamine and its 4–methyl, 4–fluoro, and 4– trifluoromethyl derivatives. Rate constants for base hydrolysis of the (substituted) benzylamine derivatives are also reported for some Me2CO-H2O and DMSO-H2O solvent mixtures. Reaction is faster in all these binary aqueous mixtures, mainly due to the higher chemical potentials of hydroxide ion.
16 citations
TL;DR: In this paper, a fluid model of magnetically confined surface-wave plasma columns maintained in a diffusion-controlled regime is given, where the propagation of the Trivelpiece-Gould mode which sustains the discharge is in a strong magnetic field.
Abstract: A fluid model of magnetically confined surface-wave plasma columns maintained in a diffusion-controlled regime is given. The propagation of the Trivelpiece-Gould mode which sustains the discharge is in a strong magnetic field. The self-consistent wave-discharge behaviour is ensured by a nonlocal nonlinearity involving transport (diffusion) along the external magnetic field. Simultaneous variation along the discharge's length of the plasma density and maintenance field intensity is the final result presenting the axial structure of the discharge.
13 citations
12 citations
TL;DR: In this article, the authors demonstrate that the C40 cluster molecule is easily formed to Td symmetry structure and its ground state is 5A2 open shell with four unpaired electrons.
Abstract: Herein we demonstrate that the C40 cluster molecule is easily formed to Td symmetry structure and its ground state is 5A2 open shell with four unpaired electrons. These four unpaired electrons are located at the tip points of the Td symmetry structure. This work also indicates that these four unpaired electrons can easily react with a single valence atom, such as hydrogen or halogen atoms, to form a stable carbon hydrogen cluster molecule, C40H4, and carbon halogen cluster molecules, C40X4 (X=F, Cl, Br, I), respectively. The PM3 semiempirical molecular orbital method from Gaussian 94W computer program package was applied very well to these cluster molecules. According to the results in this study, the structures of geometrical optimization, ionization potential, energy gap, heat of formation, atomization energy, vibration frequency, and the remaining data of C40H4 and C40X4 cluster molecules. The above-calculated data prove that these unknown cluster molecules are stable and have a stable capacity similar to 1,3,5,7-tetrahaloadamantane molecules. They can be possibly synthesized experimentally in the near future. © 1998 John Wiley & Sons, Inc. Int J Quant Chem 68: 273–284, 1998
TL;DR: In this paper, the built-in electric fields and interfacial state densities in a series of oxide-GaAs heterostructures fabricated by in situ molecular beam epitaxy were studied using room temperature photoreflectance.
Abstract: Built-in electric fields and interfacial state densities (Dit) in a series of oxide–GaAs heterostructures fabricated by in situ molecular beam epitaxy were studied using room temperature photoreflectance. The samples investigated were air-, Al2O3–Ga2Ox–, and Ga2O3(Gd2O3)–GaAs. We found that the built-in electric fields are 48, 44, and 38 kV/cm for air-, Al2O3-, and Ga2Ox–GaAs samples, respectively. For the Ga2O3(Gd2O3)–GaAs sample, the built-in electric field is negligibly small, indicating a very low interfacial state density. Estimated by the low field limit criterion, Dit is less than 1×1011 cm−2 eV−1. Our results on the Ga2O3(Gd2O3)–GaAs sample are consistent with the data obtained previously using capacitance–voltage measurements in quasistatic/high frequency modes and photoluminescence measurements.
TL;DR: Optical parameters of undoped semi-insulating GaAs before and after neutron irradiation are reported in this paper, where the Kramers-Kronig dispersion analysis applied to nearly-normal reflectance data was carried out to determine the optical constants and associated parameters.
Abstract: Optical parameters of undoped semi-insulating GaAs before and after neutron irradiation are reported. Optical properties in the photon energy range between 1.5–6.0 eV were investigated. The Kramers–Kronig dispersion analysis applied to nearly-normal reflectance data was carried out to determine the optical constants and associated parameters.
TL;DR: In this article, the cobaltacarborane anion labelled with 60Co was used to study the solvent extraction and stability of its ion associates with a series of organic nitrogen base cations or quaternary salts, some of which are psychoactive.
Abstract: The cobaltacarborane anion labelled with 60Co was used to study the solvent extraction and stability of its ion associates with a series of organic nitrogen base cations or quaternary salts, some of which are psychoactive. The aqueous phase was 0.1 M HCl, the organic phase was chloroform. The extraction constants of the ion associates were calculated. A method was devised for competitive extraction of ion associates with additional dye anions which are used in the extraction-photometric determination of selected bases.
Journal Article•
TL;DR: Thomas Jefferson and historical self-construction: The Earth Belongs to the Living? The Historian: Vol. 61, No. 2, pp. 289-310 as discussed by the authors, 1998
Abstract: (1998). Thomas Jefferson and Historical Self‐Construction: The Earth Belongs to the Living? The Historian: Vol. 61, No. 2, pp. 289-310.
11 Nov 1998
TL;DR: In this paper, the authors discuss implementations of the wavelet transform using acousto-optic correlators and smart pixels as spatial light modulators, and present a specific smart pixel implementation consisting of analog liquid crystal integrated on silicon 2.0-micrometers CMOS circuitry.
Abstract: Wavelet transforms have found many practical applications in signal processing, including image processing, pattern recognition, and feature extraction. Since the wavelet transform is fundamentally given by the correlation of an input signal with a family of daughter wavelets, any real- time correlator can be used to implement the wavelet transform. Optical correlators are particularly well suited to this application, since the wavelet transform of a 1D signal produces a 2D wavelet transform. In this paper,w e discuss implementations of the wavelet transform using acousto-optic correlators and smart pixels as spatial light modulators. Smart pixels integrate both electronic processing and optical devices in a 2D array, which takes full advantage of the programmability of electronics and the parallel processing of optical devices. We describe a specific smart pixel implementation consisting of analog liquid crystal integrated on silicon 2.0-micrometers CMOS circuitry; and present experimental results of the wavelet transform implementation. An acousto-optic architecture for real-time wavelet correlators using this device will also be presented.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
TL;DR: There appeared to be a relationship between the degree of chlorination of the phenols and inhibition of zeta-crystallin activity, and the position of the chlorine substituent on the phenol may also influence the potency of these compounds.
Abstract: Chlorophenols comprise a major class of environmental contaminants. They are extensively used as insecticides, fungicides, mold inhibitors, antiseptics and disinfectants. We found some of these compounds to be strong inhibitors of crystallin. This oxidoreductase enzyme was isolated from camel lens and its enzymatic activity was inhibited by the chlorophenols tested in a time-independent but concentration-dependent manner. 2,4,5-Trichlorophenol was the most potent inhibitor (IC50 = 3μM; Ki=3.2μM) whereas 4-chlorophenol was the least potent (IC50 = 4.1 mM). There appeared to be a relationship between the degree of chlorination of the phenols and inhibition of crystallin activity. The position of the chlorine substituent on the phenol may also influence the potency of these compounds.
03 Nov 1998
TL;DR: Other approaches to oversampling A/D conversion incorporating space-time processing of optical signals leading to ultra-high resolution at very high speed are described.
Abstract: The majority of the signals encountered in nature ar analog while the preferred method of processing these signals is digital. Digital signal processors provide higher resolution, improved flexibility and functionality, and improved noise immunity over its analog counterparts. As a result, the analog-to-digital, (A/D) interface is generally considered to be the most critical part of any signal acquisition and processing systems. Because of the difficulty in achieving high-resolution and high-speed A/D converters, this A/D interface has been and continues to be a barrier to the realization of high-speed, high-throughput systems. Electronic A/D techniques have been investigated but appear to be limited. (Sigma) (Delta) techniques have been successful in providing high-resolution converters but only for audio frequency signal. Optical approaches have also ben investigated to leverage the wide bandwidth and parallelism of optics but most have been limited by the component linearity, device speed, or dynamic range. We previously proposed and demonstrate an optical approach to A/D conversion based on oversampling techniques using a modification of the (Sigma) (Delta) architecture and multiple quantum well modulators as the optical devices. Here we describe other approaches to oversampling A/D conversion incorporating space-time processing of optical signals leading to ultra-high resolution at very high speed.
TL;DR: In this paper, the HF/6−31G∗ ab initio method was applied very well in tricyclo[3,3,1,13,7]-decane and their silicon-carbon mixed derivatives, C10 − nSinH16 (n = 0, 4, 6, 10).
Abstract: The HF/6–31G∗ ab initio method which from Gaussian 94W program packages was applied very well in tricyclo[3,3,1,13,7]-decane, tricyclo[3,3,1,13,7]decsilane and their silicon-carbon mixed derivatives, C10 − nSinH16 (n = 0, 4, 6, 10). After the work, the structures of geometrical optimization, ionization potentials, HOMO energies, LUMO energies, energy gaps, heat of formations, atomization energies, vibration frequencies of these molecules were obtained. The above calculation results prove that tricyclo[3,3,1,13,7]decsilane and silicon-carbon mixed derivatives at present work suggest that they should be stable, and their stable capacity is similar to tricyclo[3,3,1,13,7]decane molecule. It is quite possible that they can be synthesized experimentally in the near future.
09 Oct 1998
TL;DR: In this article, a photorefractive holographic interferometer is modified to implement the wavelet transform, and a potential application of this architecture known as progressive pattern recognition is discussed.
Abstract: In this paper, we describe how a photorefractive holographic interferometer may be modified to implement the wavelet transform. By placing phase-only spatial light modulators, such as acousto-optic devices, in the optical path of the sample and reference beams, it is possible to perform correlations on the phase modulated signals and then convert them into intensity modulated signals for detection and signal processing. We discuss a potential application of this architecture known as progressive pattern recognition using the wavelet transform.
TL;DR: Smart pixel arrays can function as spatial light modulators providing additional electronic processing features at each individual pixel and therefore are naturally well-suited to realize the wavelet transform.
Abstract: Recently, there has been a great deal of interest in the application of wavelet transforms to signal processing applications. Fundamentally, the wavelet transform of a signal is the correlation of the signal with a basis function derived from a mother wavelet and its called versions called daughter wavelets. Thus any real-time correlator can be sued for the implementation of the wavelet transform. Since a 1D input signal produces a 2D wavelet transform, optical correlators provide a natural advantage over conventional electronic implementations. Examples of optical correlation architecture include the VanderLugt correlator, the joint transform correlator and its derivative, the quasi-Fourier transform joint transform correlator. Any optical correlator architecture can be used to implement the wavelet transform provided a suitable spatial light modulator is used to convert the electrical input signal into an appropriate optical signal. The concept of the smart pixel is to integrate both electronic circuitry and individual optical devices on a common integrated circuit to take advantage of the complexity and programmability of electronic processing circuits and the switching speed of optical devices. Arrays of these smart pixels would then bring with them the advantage of parallelism that optics provides. Smart pixel arrays can function as spatial light modulators providing additional electronic processing features at each individual pixel and therefore are naturally well-suited to realize the wavelet transform.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
TL;DR: In this article, the evolution of plane and spherical weak shock waves in dense media is described based on the momentum conservation law for a shock-wave pulse having a saw-tooth shape.
Abstract: Relations that describe the evolution of plane and spherical weak shock waves in dense media are obtained based on the momentum conservation law for a shock-wave pulse having a saw-tooth shape. With distance from the center of spherical shock-wave pulse generation, the dependences which describe its evolution asymptotically becomes those which describe the evolution of a plane pulse.
TL;DR: It was expedient to extend this approach to some other types of biological activity and to expand the circle of polycyclic effeetors of the GABA-receptor complex to include bicyclic insecticides such as endrin, endosulfan, etc.
Abstract: Information gained from modem molecular-biological and toxico-pharmacological investigations and the results of structureactivity relationship modeling led to the notion of the GABA-receptor as a multicomponent complex including various effectors, each having special binding sites of its own [2 6]. It is now commonly accepted that convulsants of the cell structure, including halogenated polycyclic compounds, interact with a picrotoxinin site of the GABA-reeeptor complex (GRC), this interaction having an electron-conformational character and showing strongly pronounced stereospecificity. This was dearly demonstrated for the bicyclic insecticides (BCIs) such as endrin, endosulfan, etc., by constructing models relating the activity in vitro to integral characteristics of their spatial and electronic structures [I]. It was therefore expedient to extend this approach to some other types of biological activity and to expand the circle ofpolycyclic effeetors of the GABA-receptor complex.
TL;DR: In this paper, the synchrotron and wiggler polarizations are mutually orthogonal so that one or the other can be easily eliminated to provide essentially monochromatic radiation.
Abstract: Recent work has described wigglers in which the radiating electron beam circulates azimuthally within a toroidal tube where a surrounding permanent magnet structure keeps the beam on a mean circular path and simultaneously provides the field periodicity for wiggler action. Both the mean field and the periodic field are in the axial direction so that the resulting synchrotron and wiggler radiations are both polarized in the principal toroidal plane. The present work analyzes a structure in which the synchrotron and wiggler polarizations are mutually orthogonal so that one or the other can be easily eliminated to provide essentially monochromatic radiation. This is accomplished by an azimuthally periodic arrangement of magic ring sections that form a toroidal tube. These are oriented with their axial field components constant and equal and their radial components equal but alternating radially outward and inward in direction. The constant axial field holds the electron beam in a circular path while the alternating radial field provides the wiggler action. The wiggler radiation has n times the frequency of the synchrotron radiation where n is the number of azimuthal periods per circuit.
02 Jul 1998
TL;DR: In this article, the major stages of the pointing and tracking process were analyzed based on a mathematical model presented in references, and an analysis of the method was performed, in order to increase the reliability of optical links.
Abstract: A bi-directional pointing and tracking system is needed in order to establish the optical link between two optical transceivers located in two separated points at the ground or on satellites. That usually suppose the presence of a separate laser transmitter an optical beacon used for pointing and tracking purposes. The major stages of the pointing and tracking process were analyzed based on a mathematical model presented in references. In order to increase the reliability of optical links a new optical beacon is purposed and, consequently a new pointing and tracking method is developed. This method requires only communication laser transmitters and uses their optical beams for pointing and tracking process, additionally giving the possibility to increase the signal to noise ratio at the communication receiver. A mathematical model of such a system is developed and an analysis of the method is performed.