NAVAL ENIGMA: M4 AND ITS ROTORS

The wiring of rotors in the naval version of Enigma is given (including that of beta and gamma) and events leading to the introduction of Triton, a cipher for Atlantic U-boats, are described. It is shown that an alpha rotor did not enter service, and that Triton became operational in October 1941.     

Spanish Enigma: A History of the Enigma in Spain

Abstract

The presentation of a brief study of the use of Enigma Machines in Spain, during the Spanish Civil War (1936–1939) and later, until their final replacement.     

Quantification of Fatty Acids and their Regioisomeric Distribution in Triacylglycerols from Porcine and Bovine Sources Using 13C NMR Spectroscopy

The uptake of specific fatty acids in humans is dependent on their position on the glycerol backbone. There is a great interest in methods that can access this information fast and accurately. By way of high-resolution NMR, we have analyzed TAG extracted from pig and beef tissues and obtained quantitative data for the composition and regioisomeric distribution of all major unsaturated fatty acids usually found in these source materials, using a combination of manual integration and deconvolution of ¹³C NMR spectra. In addition, we have developed a method for determining composition and regioisomeric distribution of the two main saturated fatty acids found in pork (16:0, 18:0). The results are discussed in relation to species-specific genetic characteristics of fatty acid and TAG biosynthesis. The developed method could support decisions related to breeding for desired fatty acid profiles, and stimulate further methodology developments using high field NMR.     

Replacement and component rules in hierarchically ordered mathematics rule learning tasks.

Investigated ordered and equivalence relations among hierarchically arranged fraction identification tasks to determine whether hierarchical ordering among fraction identification problems reflected the replacement of simple rules by complex rules. 456 middle-class 2nd, 3rd, and 4th graders were asked to identify fractional parts of sets of objects. Latent class techniques revealed that Ss applied rules that were adequate for simple problems but had to be replaced to solve more complex problems. (9 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Solution algorithms for nonlinear structural problems

The article discusses characteristic types of nonlinearities in structural systems. Various ways of illustrating such nonlinearities are suggested. Mathematical equations that form the basis for alternative numerical solution algorithms are stated. The use of the current stiffness parameter for characterizing nonlinear systems is discussed. Some new formulations and applications of this parameter are suggested. A new class of solution techniques utilizing simultaneous iteration on the loading parameter as well as the displacements is also proposed. By these techniques it is not necessary to formulate a nonlinear stiffness matrix and incrementation of displacement pattern can be used instead of load incrementation. No special load reversal criterion is normally required for passing limit points.     

Transaction processing using remote procedure calls (RPC) for a heterogeneous distributed clinical information system

The Johns Hopkins Hospital is developing a distributed clinical information system that integrates functionally several UNIX, IBM MVS/CICS and MUMPS computer systems. Distributed application development is accomplished by interprocess communications across Ethernet using remote procedure calls. The remote procedure call (RPC) protocol provides a standard approach to the development of distributed applications using the metaphor of a subroutine call. The Sun Microsystems RPC and XDR (external data representation) protocols have been implemented in these environments. The systems, the distributed model, RPC implementations and applications examples are discussed.