Showing papers by "Military Academy published in 1992"
TL;DR: In this article, a correlator using a gray scale amplitude modulator for an input device and a grey scale phase modulator in the filter plane was constructed using two liquid crystal cells from a commercially available color projection television.
Abstract: We have constructed a correlator using a gray scale amplitude modulator for an input device and a gray scale phase modulator in the filter plane. The spatial light modulators used in the correlator are two of the three liquid crystal cells from a commercially available color projection television. The cells (twisted nematic liquid crystals) may be operated in an amplitude mostly or phase mostly mode by selecting the polarization of the light and the operating bias voltage. We show the Jones matrix analysis of the laboratory measurements and the corresponding operating curves. Signal to noise ratios on the order of 100:1 have been observed for some test objects using simple phase mostly filters.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
17 citations
TL;DR: In the presence of a catalytic amount of 60% perchloric acid, 4-acetyl-3-substituted sydnones were obtained more conveniently with greater yields by the sonochemical reaction of 3 -substitized sydnone with acetic anhydride as discussed by the authors.
Abstract: In the presence of a catalytic amount of 60% perchloric acid, 4-acetyl-3-substituted sydnones were obtained more conveniently with greater yields by the sonochemical reaction of 3-substituted sydnone with acetic anhydride. Some 4-acetylsydnones which are difficult to synthesize by a known process were obtained in 17-68% yields.
4-Bromo-3-(bromoaryl)sydnones with activated zinc powder dispersed in methanol were debrominated regioselectively by ultrasound in high yields (60-96%). 3-(2′-/4′-Amino-3′,5′-dibromophenyl)sydnone is synthesized easily from 3-(2′/4′-aminophenyl)sydnone by reduction, bromination and debromination subsequently.
13 citations
TL;DR: Diazotized primary artomatic amines4 coupled with the ketosulfones1-3 in ethanol in the presence of sodium acetate at 0°C to afford the corresponding hydrazones5-7 as mentioned in this paper.
Abstract: Diazotized primary artomatic amines4 coupled with the ketosulfones1–3 in ethanol in the presence of sodium acetate at 0°C to afford the corresponding hydrazones5–7. Also diazotized 3-aminopyrazoles14 coupled with1–3 in ethanolic sodium acetate to give the pyrazolotriazines18–20 in good yields. Compounds5–7 and18 can also be obtained from the reaction of hydrazidoyl halides8–10 and21 with sodium benzenesulfinate. The hydrazones11–13 can easy be oxidized to the hydrazones5–7, using hydrogen peroxide in acetic acid.
12 citations
TL;DR: Furoylhydroximoyl chloride3 as mentioned in this paper reacts with 2-aminopyridine, 2-amino-polymorphine, O-phenylenediamine and aminothiophenol to obtain aminophyridine derivatives.
Abstract: Furoylhydroximoyl chloride3 reacted with 2-aminopyridine, 2-aminopyrimidine,O-aminophenol,O-phenylenediamine and aminothiophenol to afford imidazo[1,2-a]pyridine6, imidazo[1,2-a]pyrimidine8, benzoxadiazine10, nitrosobenzopyrazine13a and nitrosobenzothiazine13b, respectively. Isoxazoline18 and pyrrolidino[3,4-d]isoxazolin-4,6-dione derivatives19a and19b obtained by the reaction of3 with acrylonitrile and N-arylmaleimide. Hydroximoyl chloride3 reacted with thiophenol and sodium benzenesulfinate to yield furylglyoxaloxime16a and16b, respectively. Hydroximoyl chloride3 reacted also with some active methylene compound to give isoxazole derivatives20–23, respectively.
9 citations
TL;DR: In this paper, the temperature of a non-stationary Kerr-Newman black hole is given and the temperature is homogeneous everywhere at the event horizon and only depends on the time.
Abstract: Following a new method developed by the authors the temperature of a non-stationary Kerr-Newman black hole is given. The temperature is homogeneous everywhere at the event horizon and only depends on the time.
7 citations
TL;DR: In this article, 2-mercaptobenzimidazole and 2-aminothiazoles were used for the reaction of hydrazidoyl halides with 3-substituted 2-arylazothiazolo-[3,2-a] benzimidrazole6a-c, respectively.
Abstract: Hydrazidoyl halides were condensed with 2-mercaptobenzimidazole2 yielding4a-c which were cyclized to the corresponding 3-substituted 2-arylazothiazolo-[3,2-a] benzimidazole6a-c, respectively. Imidazo-[2,1-b] thiazoles9, 12, 15, and16 were obtained by the reaction of hydrazidoyl halides1 with 2-mercapto 4,5-dihydroimidazole3 and 2-aminothiazoles10. The structures of the products were established on the basis of their elemental analysis and spectral data studies.
6 citations
Journal Article•
TL;DR: It was found that skin lesions in sarcoids and sarcoidosis do not differ regarding either in clinical or histological manifestations, and the changes in the functional activity of monocytes and macrophages were the same.
Abstract: Twenty patients with cutaneous sarcoidosis and 21 patients carrying isolated skin sarcoids were studied. (We use the term 'sarcoid' to emphasize that exclusively skin was altered.) Both groups were compared by clinical and histological patterns and certain data concerning the state of the mononuclear phagocyte system (MPS). It was found that skin lesions in sarcoids and sarcoidosis do not differ regarding either in clinical or histological manifestations. The changes in the functional activity of monocytes and macrophages were the same. The data obtained allow us to suggest that sarcoids should be regarded as a systemic disease connected with changes in the MPS reaction.
6 citations
TL;DR: In this article, the bending stress in the root fillets of gear teeth having convex, circular-arc profiles has been calculated using a new analytic model for variable surface pressure distribution, where the gear tooth is modeled as a wedge with the load applied at the apex.
5 citations
TL;DR: In this paper, an incremental three-dimensional constitutive relation for concrete has been developed, where linear anisotropic and path-dependent behavior is modeled by updating the stiffness matrix at each load increment.
Abstract: An incremental three-dimensional constitutive relation for concrete has been developed. The linear anisotropic and path-dependent behavior is modeled by updating the stiffness matrix at each load increment.
4 citations
TL;DR: In two cases, heel defects with loss of both bony and soft tissue, resulting from gun-shot and mine explosion injuries, were successfully reconstructed using an osteocutaneous free groin flap based on the deep circumflex iliac artery (DCIA).
Abstract: In two cases, heel defects with loss of both bony and soft tissue, resulting from gun-shot and mine explosion injuries, were successfully reconstructed using an osteocutaneous free groin flap based on the deep circumflex iliac artery (DCIA). The follow-up periods ranged from 8 to 17 months. Functionally useable feet were obtained in both cases.
3 citations
TL;DR: In this paper, the salient features and concepts of a model developed in part I of the paper are reviewed and extended to include dilatancy and shear compaction which are determined from uniaxial stress-strain relationships.
Abstract: The salient features and concepts of a model developed in part I of the paper are reviewed. The model is extended to include dilatancy and shear compaction which are determined from uniaxial stress-strain relationships.
25 Nov 1992
TL;DR: In this paper, the authors review the field of digital phase grating optics and discuss some of their modern applications, including Fourier domain signal processing, matched filtering, optical interconnects, and switches for digital optical computing.
Abstract: Binary holographic phase gratings, also known as Dammann gratings, can be electronically synthesized by using the acousto-optic effect. We review the field of digital phase grating optics, and discuss some of their modern applications. We present the underlying grating theory and describe an approach to realizing these gratings in an acousto-optic device. Potential applications include Fourier domain signal processing, matched filtering, optical interconnects, and switches for digital optical computing.
TL;DR: In this article, the most recent ab initio potentials for H2(1∑g+), which include relativistic, adiabatic and radiative corrections, were used to calculate the spectrum of quasibounded states.
Abstract: The most recent ab initio potentials for H2(1∑g+), which include relativistic, adiabatic and radiative corrections, were used to calculate the spectrum of quasibound states. The levels, widths and tunneling permeability of resonant states were also studied by the quantum phase-shift method. A new set of relevant resonance states for the calculations of atomic recombination of hydrogen is indicated by the present work. In comparison with the previous studies, significant improvements have been found for the resonances.
TL;DR: In this paper, the fused B2O3-SiO2 was added to the calcined ferrites during the milling stage to enhance the magnetic properties; (BH)max can reach 3.0 MGOe for the ferrite sintered at 1220°C for 2 h.
Abstract: Strontium ferrites (SrO · 5.5Fe2O3) were prepared using hot-rolled mill scale as a source of iron oxides. Calcination was performed at 1200°C for 2 h. The fused B2O3-SiO2, with various mole ratios of B2O3 to SiO2, was added to the calcined ferrites during the milling stage. The ferrites were formed anisotropically. The fused additives are quite effective to enhance the magnetic properties; (BH)max can reach 3.0 MGOe for the ferrite sintered at 1220°C for 2 h. In general, (BH)max is independent of the mole ratio of B2O3 to SiO2 and dominantly influenced by the sintering temperature. The addition of 0.3 or 0.5 wt% fused additives showed no significant difference in the magnet quality. The quality of the magnet was decreased with increasing mole ratio of B2O3 to SiO2 when unfused B2O3-SiO2 was used under the same processing conditions.
01 Apr 1992
TL;DR: In this article, the CO(v,J) product state distributions were probed using an IR tunable diode laser and the results showed that the low J population is the result of rotational relaxation of the nascent CO distribution.
Abstract: The title reaction was studied by probing the CO(v,J) product state distributions. Oxygen atoms were formed by 355 nm photolysis of NO2. Photolysis produces approximately equal populations of NO(v equals 0) and NO(v equals 1). The collision energy of oxygen atoms corresponding to NO(v equals 0) is 1570 cm-1. This is above the O + OCS activation barrier of 1540 cm-1. Oxygen atoms corresponding to NO(v equals 1) do not have sufficient energy to proceed over the activation barrier, thus insuring monoenergetic collisions. CO product was probed using an IR tunable diode laser. Nascent CO distributions were extracted from the transient absorption signals using an initial slope approximation. A vibrational branching ratio of [v equals 1]/[v equals 0] = 2) was not detected. The CO(v equals 0) rotational Boltzmann plot was bimodal. The distribution for 0 = 15, the plot had a temperature of 4400 +/- 390 K. The low J population is the result of rotational relaxation of the nascent CO distribution. The high J signals are direct measure of the nascent CO population. Surprisal analysis resulted in a parameter of (Theta) R equals 3.7 +/- 0.5. Hence, the CO(v equals 0) distribution is colder than a `prior' statistical model.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
01 Apr 1992
TL;DR: In this article, the authors used time-resolved infrared diode laser spectroscopy to state selectively monitor CO produced in the ''hot'' atom reaction of H with CO2 and OCS.
Abstract: Time-resolved infrared diode laser spectroscopy has been used to state selectively monitor CO produced in the `hot' atom reaction of H with CO2 and OCS. For center of mass (CM) kinetic energies of 2.4 and 1.4 eV, respectively, CO internal excitations are substantially colder than predicted by statistical theory, with energy preferentially channeled into CM translation. In the collision energy regime of these experiments, approximately 10,000 cm-1 above the barrier, statistical rate theory is not applicable even with an intermediate.© (1992) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
TL;DR: In the early 1980s, Mexico's reaction to subversion and domestic unrest within the region was one of sympathy and even support for forces seeking to overturn the existing order as discussed by the authors.
Abstract: Contradictions arise from time to time in almost every nation's security policy. Although not normally aired publicly on network television (the U.S. being a notable exception), they are sometimes manifested in curious patterns of state behavior. It is intriguing but not surprising, therefore, to discover certain inconsistencies in the way Mexico handled challenges to security on its southern flank during the early 1980s. The policy conflict centered on Mexico's reaction to subversion and domestic unrest within the region. When this instability afflicted countries not sharing a border with Mexico (i.e., Nicaragua and El Salvador), the official position was one of sympathy and even support for forces seeking to overturn the existing order. When the residue of similar turmoil spilled over the Guatemalan border onto native soil, however, Mexican policy makers responded with much less enthusiasm. Neither guerrillas opposed to the Guatemalan government nor innocent victims fleeing Guatemalan Army repression received a hearty welcome. In part, this incoherency arose because national security thinking in Mexico was almost exclusively oriented toward the threat from within. The prevailing national security consensus offered little or no guidance for dealing with security challenges emanating from the external environment (Sereseres 1984:201-202). Hence, this border issue provides fertile ground for exploring the status of national security thinking in Mexico during the 1980s and may partially account for modifications that were subsequently made in their security policy apparatus. To conduct this exploration properly, it will be essential to examine various international and domestic factors that have impinged upon Mexican decision makers in this issue area. After establishing the context, we will review the unfolding of events along the Guatemalan border following the 1979 Nicaraguan Revolution. Having done this, it will be possible to offer an assessment of Mexico's curious response to its southern security problem.