Real-Time Display Of 3-D Computer Data Using Computer Generated Holograms

1989 ◽  
Author(s):  
Hamid Farhoosh ◽  
Yashaiahu Fainman ◽  
Kristopher Urquhart ◽  
Sing H. Lee
Keyword(s):  
Real Time ◽  
Computer Data ◽  
Computer Generated Holograms

Real-time photorealistic computer-generated holograms based on backward ray tracing and wavefront recording planes

2018 ◽  
Vol 429 ◽  
pp. 12-17 ◽  
Author(s):  
Yuan Wang ◽  
Xinzhu Sang ◽  
Zhidong Chen ◽  
Hui Li ◽  
Linmin Zhao
Keyword(s):  
Real Time ◽  
Ray Tracing ◽  
Computer Generated Holograms

scholarly journals The Impact of Computers on the Test Cell of Tomorrow

1983 ◽  
Author(s):  
Clifford F. Ash
Keyword(s):  
Data Acquisition ◽  
Real Time ◽  
Test Procedure ◽  
Processing System ◽  
Open Loop ◽  
Engine Operation ◽  
Computer Data ◽  
Automatic Data ◽  
Data Acquisition And Processing ◽  
The Impact

Rapidly increasing fuel costs, the increasing complexity of the new engines now available, along with the inaccuracies, inefficiencies and long test cycles inherent in manual testing push the cost of engine testing to unnecessary levels. One promising avenue of relief is the automation of gas turbine testing through the use of real-time computer data acquisition and processing systems. Remarkable progress has been made in the area of closed-loop or fully automatic operation of the test process from start-up using various programmable steps, recording results as dictated by the test procedure, controlling operation and a safe engine shut down. This paper discusses the successful application of a real-time computer system with both closed and open-loop capabilities. This particular system called “ADAPS™” (Automatic Data Acquisition and Processing System) handled its first 3,000 hours of engine operation without a single hardware or software interruption. Savings in manpower alone in that period was nearly 18,000 man-hours.

scholarly journals MODULE OF PROCESSING EXPERIMENTAL THERMAL CHARACTERISTICS OF MACHINE TOOLS IN REAL-TIME MODE USING HIGH ORDER DERIVATIVES

2019 ◽  
Vol 4 (5) ◽  
pp. 155-164
Author(s):  
В. Позевалкин ◽  
Vladimir Pozevalkin ◽  
И. Парфёнов ◽  
Igor' Parfenov ◽  
А. Поляков ◽  
...  
Keyword(s):  
Real Time ◽  
Machine Tools ◽  
Thermal State ◽  
Thermal Characteristics ◽  
High Order ◽  
Automated System ◽  
Software Module ◽  
Computer Data ◽  
Characteristic Points ◽  
High Level

The article presents processing module of experimental thermal characteristics of machine tools in real time using high order derivatives. It is developed in a high level programming language. This module is a part of automated system of tests and diagnostics of machines thermal state. The module is equipped with a graphical user interface; it works in real time, allows performing procedures for smoothing experimental thermal characteristics and determining their prognostic values. This allows building curves of speed, acceleration and sharpness of temperature change over the time. The developed software module implements a new algorithm based on the Horner’s method. The practice of developing algorithmic software shows that the chosen method is very convenient and effective for machine implementation, due to the absence of a division operation at each computational step. It is experimentally confirmed that the total costs of performing the calculations of high order derivatives of an arbitrary degree polynomial using the Horner’s method according to the described algorithm are acceptable for real-time calculations on a standard personal computer. Data temperature and temperature movements of the machine working bodies can be processed using the developed algorithms. In addition, this algorithm allows calculating the value of the approximating polynomial and simultaneously obtaining the values of all its derivatives at a given point. This allows to solve the problem of "shift in time by step" of the position of characteristic points.

scholarly journals Real-time terahertz meta-cryptography using polarization-multiplexed graphene-based computer-generated holograms

Nanophotonics ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 2861-2877 ◽  
Author(s):  
Hamid Rajabalipanah ◽  
Kasra Rouhi ◽  
Ali Abdolali ◽  
Shahid Iqbal ◽  
Lei Zhang ◽  
...  
Keyword(s):  
Real Time ◽  
Data Storage ◽  
Secure Communication ◽  
Information Science ◽  
Near Field ◽  
Polarization Rotation ◽  
Data Rates ◽  
Theoretical Predictions ◽  
Perfect Secrecy ◽  
Computer Generated Holograms

AbstractAs one of the cutting-edge technologies in advanced information science, wave-based cryptography is a prerequisite to enable a plethora of secure encrypting platforms which can be realized by smart multiplexing techniques together with suitable metasurface holograms (meta-holograms). Here, relying on the polarization multiplicity and re-writability of a computer-generated meta-hologram, a fully secure communication protocol is elaborately developed at the terahertz spectrum to host unique merits for exploring real-time metasurface-based cryptography (meta-cryptography) where highly restricted access of information is imposed. The proposed meta-cryptography exploits two dynamic near-field channels of a meta-hologram whose information can be instantaneously re-written without any polarization rotation and with high contrast and acceptable frequency bandwidth. The computer-generated meta-hologram is constructed based on the weighted Gerchberg–Saxton algorithm via a two-dimensional array of vertical graphene strips whose anisotropic reflection is merely determined by external biasing conditions. Several illustrative examples have been presented to demonstrate the perfect secrecy and polarization cross-talk of the proposed meta-cryptography. Numerical simulations corroborate well our theoretical predictions. As the first demonstration of dynamic THz meta-cryptography, the meta-hologram information channels can be deciphered into manifold customized messages which would be instrumental in data storage systems offering far higher data rates than electronic encryption can deliver.

Some Recent Results in Quiescent Prominence Spectrometry

1979 ◽  
Vol 44 ◽  
pp. 41-47
Author(s):  
Donald A. Landman
Keyword(s):  
Real Time ◽  
Computer System ◽  
Spectral Response ◽  
Absolute Intensity ◽  
Solar Observatory ◽  
Target Size ◽  
Small Target ◽  
Signal Averaging ◽  
Quiescent Prominence

This paper describes some recent results of our quiescent prominence spectrometry program at the Mees Solar Observatory on Haleakala. The observations were made with the 25 cm coronagraph/coudé spectrograph system using a silicon vidicon detector. This detector consists of 500 contiguous channels covering approximately 6 or 80 Å, depending on the grating used. The instrument is interfaced to the Observatory’s PDP 11/45 computer system, and has the important advantages of wide spectral response, linearity and signal-averaging with real-time display. Its principal drawback is the relatively small target size. For the present work, the aperture was about 3″ × 5″. Absolute intensity calibrations were made by measuring quiet regions near sun center.

Video real-time imaging of artificial membranes during freeze-drying by cryo-electron microscopy

1988 ◽  
Vol 46 ◽  
pp. 16-17
Author(s):  
Alan S. Rudolph ◽  
Ronald R. Price
Keyword(s):  
Real Time ◽  
Self Assembly ◽  
Freeze Drying ◽  
Video Capture ◽  
Drying Process ◽  
Artificial Membranes ◽  
The Past ◽  
Cryo Electron Microscopy ◽  
Spherical Structures ◽  
Capture Techniques

We have employed cryoelectron microscopy to visualize events that occur during the freeze-drying of artificial membranes by employing real time video capture techniques. Artificial membranes or liposomes which are spherical structures within internal aqueous space are stabilized by water which provides the driving force for spontaneous self-assembly of these structures. Previous assays of damage to these structures which are induced by freeze drying reveal that the two principal deleterious events that occur are 1) fusion of liposomes and 2) leakage of contents trapped within the liposome [1]. In the past the only way to access these events was to examine the liposomes following the dehydration event. This technique allows the event to be monitored in real time as the liposomes destabilize and as water is sublimed at cryo temperatures in the vacuum of the microscope. The method by which liposomes are compromised by freeze-drying are largely unknown. This technique has shown that cryo-protectants such as glycerol and carbohydrates are able to maintain liposomal structure throughout the drying process.

An Interactive Minicomputer Program for the Indexing and Simulation of Electron Diffraction Patterns

1976 ◽  
Vol 34 ◽  
pp. 542-543
Author(s):  
R.P. Goehner ◽  
W.T. Hatfield ◽  
Prakash Rao
Keyword(s):  
Electron Diffraction ◽  
Real Time ◽  
Pattern Analysis ◽  
Flow Diagram ◽  
Hard Copy ◽  
Time Analysis ◽  
Real Time Analysis ◽  
Transmission Electron ◽  
One Step ◽  
Diffraction Patterns

Computer programs are now available in various laboratories for the indexing and simulation of transmission electron diffraction patterns. Although these programs address themselves to the solution of various aspects of the indexing and simulation process, the ultimate goal is to perform real time diffraction pattern analysis directly off of the imaging screen of the transmission electron microscope. The program to be described in this paper represents one step prior to real time analysis. It involves the combination of two programs, described in an earlier paper(l), into a single program for use on an interactive basis with a minicomputer. In our case, the minicomputer is an INTERDATA 70 equipped with a Tektronix 4010-1 graphical display terminal and hard copy unit.A simplified flow diagram of the combined program, written in Fortran IV, is shown in Figure 1. It consists of two programs INDEX and TEDP which index and simulate electron diffraction patterns respectively. The user has the option of choosing either the indexing or simulating aspects of the combined program.

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