Public key cryptosystems : theory, application and implementation

The determination of an individual's right to privacy is mainly a nontechnical matter, but the pragmatics of providing it is the central concern of the cryptographer. This thesis has sought answers to some of the outstanding issues in cryptography. In particular, some of the theoretical, application and implementation problems associated with a Public Key Cryptosystem (PKC).The Trapdoor Knapsack (TK) PKC is capable of fast throughput, but suffers from serious disadvantages. In chapter two a more general approach to the TK-PKC is described, showing how the public key size can be significantly reduced. To overcome the security limitations a new trapdoor was described in chapter three. It is based on transformations between the radix and residue number systems.Chapter four considers how cryptography can best be applied to multi-addressed packets of information. We show how security or communication network structure can be used to advantage, then proposing a new broadcast cryptosystem, which is more generally applicable.Copyright is traditionally used to protect the publisher from the pirate. Chapter five shows how to protect information when in easily copyable digital format.Chapter six describes the potential and pitfalls of VLSI, followed in chapter seven by a model for comparing the cost and performance of VLSI architectures. Chapter eight deals with novel architectures for all the basic arithmetic operations. These architectures provide a basic vocabulary of low complexity VLSI arithmetic structures for a wide range of applications.The design of a VLSI device, the Advanced Cipher Processor (ACP), to implement the RSA algorithm is described in chapter nine. It's heart is the modular exponential unit, which is a synthesis of the architectures in chapter eight. The ACP is capable of a throughput of 50 000 bits per second

An efficient asynchronous multiplier

An efficient asynchronous serial-parallel multiplier architecture is presented. If offers significant advantages over conventional clocked versions, without some of the drawbacks normally associated with similar asynchronous techniques, such as excessive area. It is shown how a general asynchronous communication element can be designed and illustrated with the CMOS multiplier chip implementation. It is also shown how the multiplier could form the basis for a faster and more robust implementation of the Rivest-Sharmir-Adleman (RSA) public-key cryptosystem

Survival, Nest Success and Productivity of Female Common Eiders (Somateria mollissima dresseri) on Flag Island, Harspwell, Casco Bay, Maine

In 2008, we concluded the 6th and final year of what was originally designed as a 5-year study to examine survival, recruitment and recovery rates of nesting common eiders (Somateria mollissima dresseri) on Flag Island, Harpswell, Maine. The total breeding population of common eiders on Flag Island was estimated to be about 500 nesting pairs in 2008, which is at the long term estimate of approximately 500-600 nesting pairs for this island. Both the 2007 and 2008 nesting estimates were, however, a marked improvement from the 2006 estimate when only 200 hens actually nested. This low point coincided with the beginning of significant non-nesting events by hen eiders in east Casco Bay at and leading up to two significant mortality events on the wintering grounds in Massachusetts. One cause contributing to these die-offs was determined to by an RNA virus. Nest success over the duration of this study was high at 75% in 2005, 74% in 2006 to 89% in 2007. Although the percentage of nesting great black-backed gulls increased during this investigation, the overall size of the nesting gull population remained fairly constant

An efficient asynchronous multiplier

An efficient asynchronous serial-parallel multiplier architecture is presented. If offers significant advantages over conventional clocked versions, without some of the drawbacks normally associated with similar asynchronous techniques, such as excessive area. It is shown how a general asynchronous communication element can be designed and illustrated with the CMOS multiplier chip implementation. It is also shown how the multiplier could form the basis for a faster and more robust implementation of the Rivest-Sharmir-Adleman (RSA) public-key cryptosystem

Acute effect of repeated sprints on inter-limb asymmetries during unilateral jumping

The aim of the present study was to investigate the effects of multiple repeated sprints on unilateral jump performance and inter-limb asymmetries. Eighteen recreationally active males performed three single leg countermovement jumps (SLCMJ) as baseline data. The repeated sprint protocol was 6 x 40 m with 20 seconds of passive rest between each sprint. This protocol was conducted four times, each set separated by four minutes of rest. Within that rest period, subjects performed one SLCMJ on each limb after two minutes of rest. A one-way ANOVA showed significant reductions (p < 0.05; ES = -0.52 to -0.99) in jump height on both limbs after each set relative to baseline. Inter-limb asymmetries increased at each time point and ranged from 7.62-14.67%, with significant increases in asymmetry seen after sets three (p = 0.046) and four (p = 0.002). Significant increases in sprint time were shown between sprints one and six in each set (p ≤ 0.01). A fatigue index (%) was also calculated and showed an exponential increase from 5.74% (set one) to 13.50% (set four), with significant differences between all sets (p < 0.001) with the exception of sets three and four. Results from this study show that a 6 x 40 m repeated sprint protocol is a sufficient dose for implementing acute fatigue in recreationally active subjects. This was manifested by reductions in jump height at all time points and jump height asymmetries after the third and fourth sets. These findings indicate that jump height from unilateral jump testing may be a useful metric to use during the monitoring process in recreationally trained athletes

Dichlorido(4,7-diaza-1-azoniacyclo­nonane-κ2 N 4,N 7)palladium(II) p-toluene­sulfonate

The title compound, [PdCl2(C6H16N3)](C7H7SO3), consists of a PdII atom bonded to two N atoms of the 1,4,7-triaza­cyclo­nonane (TACN) ligand and two chloride ions, which define a distorted square-planar geometry. The third N atom of the TACN ligand is protonated and hydrogen bonds to the p-toluene­sulfonate anion. The Cl—Pd—Cl angle is larger than the N—Pd—N angle. The packing is dominated by layers, which are formed by the criss-crossing of two different hydrogen-bonded chains. One chain is composed of hydrogen-bonded Pd(TACNH)Cl2 + cations, while the second is formed through hydrogen bonding between the p-toluene­sulfonate anion and the Pd(TACNH)Cl2 + cation

Autoconfiguration, Registration and Mobility Management for Pervasive Computing

Special Issue of Pervasive Computing</p

Svećenik Rudolf Mikec, mučenik za vjeru otaca : (jedno novigradsko sjećanje)

Background New-onset atrial fibrillation (AF) is the most common arrhythmia in critically ill patients. Although evidence base and expert consensus opinion for management have been summarised in several international guidelines, no specific considerations for critically ill patients have been included. We aimed to establish current practice of management of critically ill patients with new-onset AF. Methods We designed a short user-friendly online questionnaire. All members of the Intensive Care Society were invited via email containing a link to the questionnaire, which comprised 21 questions. The online survey was conducted between November 2016 and December 2016. Results The response rate was 397/3152 (12.6%). The majority of respondents (81.1%) worked in mixed Intensive Care Units and were consultants (71.8%). Most respondents (39.5%) would start intervention on patients with fast new-onset AF and stable blood pressure at a heart rate between 120 and 139 beats/min. However, 34.8% of participants would treat all patients who developed new-onset fast AF. Amiodarone and beta-blockers (80.9% and 11.6% of answers) were the most commonly used anti-arrhythmics. A total of 63.8% of respondents do not regularly anti-coagulate critically ill patients with new-onset fast AF, while 30.8% anti-coagulate within 72 hours. A total of 68.0% of survey respondents do not routinely use stroke risk scores in critically ill patients with new-onset AF. A total of 85.4% of participants would consider taking part in a clinical trial investigating treatment of new-onset fast AF in the critically ill. Discussion Our results suggest a considerable disparity between contemporary practice of management of new-onset AF in critical illness and treatment recommendations for the general patient population suffering from AF, particularly with regard to anti-arrhythmics and anti-coagulation used. Amongst intensivists, there is a substantial interest in research for management of new-onset AF in critically ill patients

RATE OF DEGRADATION OF CENTRALIZED OPTIMIZATION SOLUTIONS AND ITS APPLICATION TO HIGH PERFORMANCE DOMAIN FORMATION IN AD HOC NETWORKS

Future military systems such a FCS require a robust and flexible network that supports thousands of ad hoc nodes; therefore, we must ensure the scalability of networking protocols (e.g., rout-ing, security and QoS). The use of hierarchy is a powerful solu-tion to the scaling problem, since it allows networking protocols to operate on a limited number of nodes, as opposed to the entire network. We have proposed an automated solution to dynami-cally create and maintain such hierarchy based on a combina-tion of global optimization algorithms [1] and local distributed maintenance protocols [2]. Global optimization clearly im-proves performance in a static network but, it is unclear how effective it is in a dynamic ad hoc environment. As network and node characteristics change, the optimization algorithm may use incomplete, stale, or even inaccurate metrics. In this paper, we analyze how the hierarchy created deteriorates from the optimal as network conditions change. We show that the fragility of the optimization depends on the particular cost function and the number of metrics that change. More important, we show, for the first time, that global optimization can remain effective for long periods with good cost functions, even in large dynamic ad hoc networks (where metrics may change rapidly due to node mobility and links making and breaking). This result shows that, with fast optimization algorithms such as modified Simulated Annealing [1], future military systems can use global optimiza-tion to autoconfigure domains to significantly improve perform-ance. We also show that local maintenance protocols support the global optimization mechanisms by extending the time the hierarchy remains feasible