Ophthalmic optics. Format of digital data files for data transfer for profiling of spectacle lenses

1998 ◽  
2018 ◽  
Vol 7 (2.4) ◽  
pp. 46 ◽  
Author(s):  
Shubhanshi Singhal ◽  
Akanksha Kaushik ◽  
Pooja Sharma

Due to drastic growth of digital data, data deduplication has become a standard component of modern backup systems. It reduces data redundancy, saves storage space, and simplifies the management of data chunks. This process is performed in three steps: chunking, fingerprinting, and indexing of fingerprints. In chunking, data files are divided into the chunks and the chunk boundary is decided by the value of the divisor. For each chunk, a unique identifying value is computed using a hash signature (i.e. MD-5, SHA-1, SHA-256), known as fingerprint. At last, these fingerprints are stored in the index to detect redundant chunks means chunks having the same fingerprint values. In chunking, the chunk size is an important factor that should be optimal for better performance of deduplication system. Genetic algorithm (GA) is gaining much popularity and can be applied to find the best value of the divisor. Secondly, indexing also enhances the performance of the system by reducing the search time. Binary search tree (BST) based indexing has the time complexity of  which is minimum among the searching algorithm. A new model is proposed by associating GA to find the value of the divisor. It is the first attempt when GA is applied in the field of data deduplication. The second improvement in the proposed system is that BST index tree is applied to index the fingerprints. The performance of the proposed system is evaluated on VMDK, Linux, and Quanto datasets and a good improvement is achieved in deduplication ratio.


Author(s):  
Jon R. Lindsay

This chapter investigates the Combined Air Operations Center (CAOC), the analogue to the Fighter Command Ops Room in the modern U.S. Air Force. The air force formally designates the CAOC as a weapon system, even as it is basically just a large office space with hundreds of computer workstations, conference rooms, and display screens. The CAOC is an informational weapon system that coordinates all of the other weapon systems that actually conduct air defense, strategic attack, close air support, air mobility and logistics, and intelligence, surveillance, and reconnaissance (ISR). One might be tempted to describe the CAOC as “a center of calculation,” but modern digital technology tends to decenter information practice. Representations of all the relevant entities and events in a modern air campaign reside in digital data files rather than a central plotting table. The relevant information is fragmented across collection platforms, classified networks, and software systems that are managed by different services and agencies. Thus, in each of the four major U.S. air campaigns from 1991 to 2003, CAOC personnel struggled with information friction. They rarely used the mission planning systems that were produced by defense contractors as planned, and they improvised to address emerging warfighting requirements.


1994 ◽  
Vol 48 (12) ◽  
pp. 1545-1552 ◽  
Author(s):  
Peter Lampen ◽  
Heinrich Hillig ◽  
Antony N. Davies ◽  
Michael Linscheid

JCAMP-DX has, for several years, been the standard form for the exchange of infrared spectral data. More recently JCAMP-DX protocols have been published for chemical structure data and for nuclear magnetic resonance spectroscopy. This publication presents a new JCAMP-DX data exchange protocol for mass spectrometry, covering the transport of single spectra, spectral series, and raw data files. The protocol can be implemented on any computer system and storage media. It is completely manufacturer independent. As with previous publications in this series, the aim is to provide reliable data transfer without loss of information regardless of the hardware or software involved. A comparison to the work on a binary protocol currently being carried out by the Analytical Instrument Association is also presented.


Author(s):  
R Vanitha ◽  
K Ramkumar ◽  
G Rajtilak ◽  
V Rajasekar

ABSTRACT A 37-year-old female patient reported to the hospital with a nasal defect due to carcinoma. She was previously restored with nasal prostheses, but was not satisfied with its cosmetic appeal. A computerized tomographic (CT) scan of the defect area was made and converted into 3- dimensional (3D) digital data using dedicated medical imaging software. From the 3D image, measurements of the defect were calculated and compared with various nasal fossa measurements available in the digital database. A 3D nose model which had measurements that closely matched the defect area was extracted and superimposed on the defect area and margins adjusted. The data files were then sent for rapid prototyping (RP). A RP model was fabricated which was duplicated in wax and processed. The final result was a nasal prosthesis that conformed well to the patients’ face and was also esthetically acceptable. The main advantage of computer-aided designing (CAD)-RP is that it allows trying various nasal forms on the patients face within few hours. This saves chair time, eliminates the impression step and provides patient and dentist an option of variety. How to cite this article Vanitha R, Ramkumar K, Rajtilak G, Rajasekar V. Designing a Nasal Prosthesis using CAD-RP Technology. Int J Prosthodont Restor Dent 2012;2(3):108-112.


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