Sichere Kommunikation über Abhörkanäle mit mehreren Empfängern und aktiven Störsendern

We derive a state of the art strong secrecy coding scheme for the multi-receiver wiretap channel under the joint and individual secrecy constraints. we show that individual secrecy can utilize the concept of mutual trust to achieve a larger capacity region compared to the joint one. Further, we derive a full characterization for the list secrecy capacity of arbitrarily varying wiretap channels and establish some interesting results for the continuity and additivity behaviour of the capacity.Für den Abhörkanal mit mehreren Empfängern wird ein Kodierungsschema hergeleitet unter dem gemeinsamen als auch individuellem Sicherheitskriterium. Das individuelle Kriterium basiert auf dem Konzept des gegenseitigen Vertrauens, um eine größere Kapazitätsregion zu erreichen. Weiterhin wird eine vollständige Charakterisierung der Sicherheitskapazität für den beliebig variierenden Kanals aufgestellt, sowie Eigenschaften bezüglich der Kontinuität und des Additivitätsverhalten bewiesen

Factors Influencing Companies to Engage in Voluntary Internet Financial Reporting: A Review

This paper aimed to survey the accounting literature for the supporting factors of voluntary internet financial reporting by corporations. It is generally and widely believed that the Internet may encourage companies to disclose more information and to develop websites for that purpose. However, these tendencies are limited by many concerns on the part of companies and users of companies’ financial information.     Thus, this study surveys the literature for the studies that may fall under any of the two categories. However, Studies that come under the first category have identified various factors that support voluntary internet financial disclosure. These include timeliness and updatability, cost savings, presentation flexibility and feedback, widening information provision among many others. The other category of those studies identified discouraging factors of internet financial reporting that include boarder problem, information overload, reliability, integrity, confidentiality of disclosed data, lack of regulations, access problems among other hampering factors. &nbsp

Dynamic analyses of suspension bridge structures

A method of dynamic analysis for vertical, torsional and lateral free vibrations of suspension bridges has been developed that is based on linearized theory and the finite-element approach. The method involves two distinct steps: (1) specification of the potential and kinetic energies of the vibrating members of the continuous structure, leading to derivation of the equations of motion by Hamilton's Principle, (2) use of the finite-element technique to: (a) discretize the structure into equivalent systems of finite elements, (b) select the displacement model most closely approximating the real case, (c) derive element and assemblage stiffness and inertia properties, and finally (d) form the matrix equations of motion and the resulting eigenvalue problems. The stiffness and inertia properties are evaluated by expressing the potential and kinetic energies of the element (or the assemblage) in terms of nodal displacements. Detailed numerical examples are presented to illustrate the applicability and effectiveness of the analysis and to investigate the dynamic characteristics of suspension bridges with widely different properties. This method eliminates the need to solve transcendental frequency equations, simplifies the determination of the energy stored in different members of the bridge, and represents a simple, fast and accurate tool for calculating the natural frequencies and modes of vibration by means of a digital computer. The method is illustrated by calculating the modes and frequencies of a bridge and comparing them with the measured frequencies

Engineering data and analyses of the Whittier, California earthquake of January 1, 1976

A magnitude 4.2 earthquake occurred near Whittier, California on January 1, 1976 at 09:20 Pacific Standard time. The shock was centered at 33.58N (Lat.) and 117.53W (Long.) in the Puente Hills of Los Angeles County. The ground shaking was recorded within a 14 Km (8.7 miles) radius of the instrumentally determined epicenter, and eleven strong-motion accelerograph records were obtained on 70 mm film from SMA-1 accelerographs operated as part of the U.S.G.S. Seismic Engineering Branch network. Although of relatively small magnitude, the earthquake did produce peak ground accelerations as high as 187% g, which merit an engineering analysis. The locations of the strong-motion accelerograph stations at the time of the earthquake are shown in Fig. 1. The eleven records were obtained from different structures as follows: (1) three records from a ten-story modern reinforced-concrete building in Whittier, (2) three records from the Carbon Canyon earth-dam site, (3) two records from the Brea earth-dam site, (4) two records from the Diemer Filtration Plant, and finally (5) one record from the Orange County Reservoir. Instruments located at Whittier Dam (16.4 Km from the instrumental epicenter) and at Puddingstone Dam (15.0 Km from the epicenter) were operational, but were not triggered by the event (Etheredge and Nielson, Ref. 1)

A Real Time Distributed Network Monitoring Platform (RTDNM)

Perkembangan geografi dan peningkatan saiz dalam rangkaian-rangkaian komputer menjadikan keperluan pemantauan terhadapnya menjadi semakin penting. As computer networks increase in size and expand geographically, the necessity to monitor them becomes increasingly important

Technical-Economic Analysis in the Application of Series Capacitor Compensation for Distribution Networks

Series capacitor compensation has been widely known as a successful technique of increasing the overall transmission efficiency in power systems by reducing the line reactance by a certain ratio which is defined by the term degree of compensation

Characterization and Lethality of Endotoxic Lipopolysaccharides (LPS) of Salmonellae

Salmonellae Lipopolysaccharides (LPS) could be extracted from different serovars in amounts varying from 1.5% to 5% of bacterial weight. No clear influence of motility on the amount of extracted LPS was detected. These LPS were studied by Sodium Dodecyl Sulphate Polyacrylamide gel electrophoresis (SDS-PAGE) and all of them gave one major band representing the core antigen with a molecular weight varying from 4 to 12 while some of them showed extra minor bands. The LD50 of different LPS preparations varied from 150 to 300 µg. The highest value was obtained by motile and non-motile Salmonella Dublin (300 µg each). Sensitization of mice at time of LPS injection by galactosamine resulted in the exaggeration of lethality induced by LPS preparation for up to 300 times. Keywords: Lipopolysaccharide – LPS – Salmonella– SDS-PAGE – electrophoresis