An Adaptive Block-Based Eigenvector Equalization for Time-Varying Multipath Fading Channels

In this paper we present an adaptive Block-Based EigenVector Algorithm (BBEVA) for blind equalization of time-varying multipath fading channels. In addition we assess the performance of the new algorithm for different configurations and compare the results with the least mean squares (LMS) algorithm. The new algorithm is evaluated in terms of intersymbol interference (ISI) suppression, mean squared error (MSE) and by examining the signal constellation at the output of the equalizer. Simulation results show that the BBEVA performs better than the non-blind LMS algorithm

The use of the psychiatric history interview: a study made at the Rhode Island State Hospital

Thesis (M.S.)--Boston University, 1947. This item was digitized by the Internet Archive

An Efficient and Effective Pilot Space-Time Adaptive Algorithm for Mobile Communication Systems

In this paper we present a new adaptive space-time algorithm for mitigating the effects of CCI and ISI and minimizing the probability of error in mobile communication systems, and evaluate its performance for different mobile velocities. The proposed algorithm is computationally efficient and provides better performance than the conventional RLS algorithm

The Collatz Conjecture and Integers of the Form \u3cem\u3e2\u3csup\u3ek\u3c/sup\u3eb−m\u3c/em\u3e and \u3cem\u3e3\u3csup\u3ek\u3c/sup\u3eb−1\u3c/em\u3e

One of the more well-known unsolved problems in number theory is the Collatz (3n + 1) Conjecture. The conjecture states that iterating the map that takes even n ∈ N to n/2 and odd n to (3n+1)/2 will eventually yield 1. This paper is an exploration of this conjecture on positive integers of the form 2kb−m and 3kb−1, and stems from the work of the first author\u27s Senior Seminar research. We take an elementary approach to prove interesting relationships and patterns in the number of iterations, called the total stopping time, required for integers of the aforementioned forms to reach 1, so that our results and proofs would be accessible to an undergraduate. Our results, then, provide a degree of insight into the Collatz Conjecture

Determining Biases in the Card-Chameleon Cryptosystem

Throughout history, spies, soldiers, and others have relied on so-called {\em hand ciphers} to send encrypted messages. Since the creation of Pontifex (also known as Solitaire) by Bruce Schneier in 1999, a number of hand ciphers utilizing a standard deck of playing cards have emerged. Since there are $52! \approx 2^{225.58}$ possible ways to order a deck of cards, there are over 225 bits of entropy in a well-shuffled deck of cards. Theoretically, this can provide enough security to rival modern computer-based cryptosystems. In this paper, we describe and analyze one such playing card cipher, Card-Chameleon, created by Matthew McKague. Our analysis reveals new weaknesses in this cryptosystem, particularly the tendency for a letter to encrypt to itself. This bias makes it easy to recover the plaintext if it is encrypted into multiple different ciphertexts. We will describe variations of Card-Chameleon which significantly reduced these weaknesses but did not completely eliminate them

VRAKA—A Probabilistic Risk Assessment Method for Potentially Polluting Shipwrecks

Shipwrecks around the world contain unknown volumes of hazardous substances which, if discharged, could harm the marine environment. Shipwrecks can deteriorate for a number of reasons, including corrosion and physical impact from trawling and other activities, and the probability of a leakage increases with time. Before deciding on possible mitigation measures, there are currently few comprehensive methods for assessing shipwrecks with respect to pollution risks. A holistic method for estimating environmental risks from shipwrecks should be based on well-established risk assessment methods and should take into account both the probability of discharge and the potential consequences. The purpose of this study was therefore to present a holistic risk assessment method for potentially polluting shipwrecks. The focus is set to developing a method for estimating the environmental consequences of potential discharges of hazardous substances from shipwrecks and to combine this with earlier research on a tool for estimating the probability of discharge of hazardous substances. Risk evaluation should also be included in a full risk assessment and is the subject of further research. The consequence assessment was developed for application in three tiers. In Tier 1, the probability of discharge and possible amount of discharge are compared to other shipwrecks. In Tier 2, a risk matrix, including a classification of potential consequences, is suggested as a basis for assessment and comparison. The most detailed level, Tier 3, is based on advanced tools for oil spill trajectory modeling and sensitivity mapping of the Swedish coast. To illustrate the method an example application on two wrecks is presented. Wreck number 1 present a lower probability of discharge and a lower consequence in a Tier 1 and Tier 3 assessment. For the Tier 2 consequence assessment, the two example wrecks present equal consequence. The tool for estimating the probability of discharge of hazardous substances from shipwrecks, and the approach for consequence estimation, offers a comprehensive method for assessing the risks presented by potentially polluting shipwrecks. The method is known as VRAKA (short for shipwreck risk assessment in Swedish) and provides decision support, facilitating prioritization of risk mitigation measures enabling efficient use of available resources

Hantering och rapportering av risk

Syftet med uppsatsen är att diskutera utformning och effekter av intern hantering och extern rapportering av risk i tre börsnoterade företag. Empirin består av presentationer av tre svenska börsnoterade företags arbete med och syn på hantering och rapportering av risk. Presentationerna baseras på intervjuer med riskansvariga på företagen samt företagens årsredovisningar. De studerade företagens externa rapportering skiljer sig åt både i utformning och innehåll, vilket minskar jämförbarheten mellan företagen. Samtliga företag anser att riskrapportering är en konkurrensfördel och det kan ses som ett incitament till att lämna frivilliga upplysningar. Det finns även en tendens till att riskrapportering hos företag inom samma bransch blir likformig. Företagen anser att de regleringar som finns avseende riskupplysningar är tillräckliga, men resultatet av denna studie visar att det företag som följer striktast reglering har den mest transparenta riskrapporteringen.The purpose of our study is to discuss the design and effects of internal risk management and external reporting of risk in three listed companies. The empirical material consists of presentations of how three Swedish listed companies view and work with risk management and risk reporting. The presentations are based on interviews with risk managers and corporate annual reports. The result shows that the three examined companies external reports differ both in form and content, which reduce the comparability between companies. All companies consider risk reporting a competitive advantage, which can be seen as an incentive to make voluntary disclosures. There is also a tendency for risk reporting among companies within the same industry to become uniform. Companies find the current regulations regarding risk disclosures as sufficient, but this study show that the company with the strictest regulation also has the most transparent risk reporting