525 research outputs found
LANDSAT-4 and LANDSAT-5 Multispectral Scanner Coherent Noise Characterization and Removal
A technique is described for characterizing the coherent noise found in LANDSAT-4 and LANDSAT-5 MSS data and a companion technique for filtering out the coherent noise. The techniques are demonstrated on LANDSAT-4 and LANDSAT-5 MSS data sets, and explanations of the noise pattern are suggested in Appendix C. A cookbook procedure for characterizing and filtering the coherent noise using special NASA/Goddard IDIMS functions is included. Also presented are analysis results from the retrofitted LANDSAT-5 MSS sensor, which shows that the coherent noise has been substantially reduced
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Of Arsenic and Old Laws: Looking Anew at Criminal Justice in Late Imperial China
On the Limits of Grand Theory in Comparative Law
I am pleased that the American Association for the Comparative Study of Law has decided to focus upon the legal systems of East Asia this year, and flattered that Professor Dan Henderson, who has organized today\u27s program, has asked me to speak about the question of comparability with respect to China. In so doing, Professor Henderson is clearly heeding Deng Xiaoping\u27s message to turn to youth-albeit in this case, callow youth. Since he has been kind enough to do so, I hope that you will be equally kind in not blaming him for my remarks. This talk is dedicated to the memory of Ted L. Stein, a law school classmate and friend who was a brilliant young specialist in international law until his untimely death in an accident in June of 1985. Although only thirty-two when he died, Ted already was much accomplished professionally. I will remember and miss Ted, though, as much for his personal attributes as for his professional achievements, for he was an individual of extraordinary character. It is truly a privilege to invoke his memory in conjunction with this presentation
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Ventures in the China Trade An Analysis of China's Emerging Legal Framework for the Regulation of Foreign Investment
In this Article, Messrs. Alford and Birenbaum examine laws and regulations recently promulgated by the People's Republic of China to govern the conduct of business and investment in China. After establishing the cultural, historical, bureaucratic and developmental contexts within which the authors believe these laws and regulations must be understood, they comprehensively examine and discuss the new legal pronouncements
Some Effects of Horizontal-Tail Position on the Vertical-Tail Pressure Distributions of a Complete Model in Sideslip at High Subsonic Speeds
An investigation has been made in the Langley high-speed 7- by 10-foot tunnel of some effects of horizontal-tail position on the vertical-tail pressure distributions of a complete model in sideslip at high subsonic speeds. The wing of the model was swept back 28.82 deg at the quarter-chord line and had an aspect ratio of 3.50, a taper ratio of 0.067, and NACA 65A004 airfoil sections parallel to the model plane of symmetry. Tests were made with the horizontal tail off, on the wing-chord plane extended, and in T-tail arrangements in forward and rearward locations. The test Mach numbers ranged from 0.60 to 0.92, which corresponds to a Reynolds number range from approximately 2.93 x 10(exp 6) to 3.69 x 10(exp 6), based on the wing mean aerodynamic chord. The sideslip angles varied from -3.9 deg to 12.7 deg at several selected angles of attack. The results indicated that, for a given angle of sideslip, increases in angle of attack caused reductions in the vertical-tail loads in the vicinity of the root chord and increases at the midspan and tip locations, with rearward movements in the local chordwise centers of pressure for the midspan locations and forward movements near the tip of the vertical tail. At the higher angles of attack all configurations investigated experienced outboard and rearward shifts in the center of pressure of the total vertical-tail load. Location of the horizontal tail on the wing- chord plane extended produced only small effects on the vertical-tail loads and centers of pressure. Locating the horizontal tail at the tip of the vertical tail in the forward position caused increases in the vertical-tail loads; this configuration, however, experienced considerable reduction in loads with increasing Mach number. Location of the horizontal tail at the tip of the vertical tail in the rearward position produced the largest increases in vertical-tail loads per degree sideslip angle; this configuration experienced the smallest variations of loads with Mach number of any of the configurations investigated
Theoretical and Experimental Investigation of the Subsonic-Flow Fields Beneath Swept and Unswept Wings with Tables of Vortex-Induced Velocities
The flow-field characteristics beneath swept and unswept wings as determined by potential-flow theory are compared with the experimentally determined flow fields beneath swept and unswept wing-fuselage combinations. The potential-flow theory utilized considered both spanwise and chordwise distributions of vorticity as well as the wing-thickness effects. The perturbation velocities induced by a unit horseshoe vortex are included in tabular form. The results indicated that significant chordwise flow gradients existed beneath both swept and unswept wings at zero lift and throughout the lift range. The theoretical predictions of the flow-field characteristics were qualitatively correct in all cases considered, although there were indications that the magnitudes of the downwash angles tended to be overpredicted as the tip of the swept wing was approached and that the sidewash angles ahead of the unswept wing were underpredicted. The calculated effects of compressibility indicated that significant increases in the chordwise variation of flow angles and dynamic-pressure ratios should be expected in going from low to high subsonic speeds
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