Efficient non-malleable commitment schemes

We present efficient non-malleable commitment schemes based on standard assumptions such as RSA and Discrete-Log, and under the condition that the network provides publicly available RSA or Discrete-Log parameters generated by a trusted party. Our protocols require only three rounds and a few modular exponentiations. We also discuss the difference between the notion of non-malleable commitment schemes used by Dolev, Dwork and Naor [DDN00] and the one given by Di Crescenzo, Ishai and Ostrovsky [DIO98]

An Assessment of an Experimental Surgery Scheme in General Practice

A study of aspects of the work and of the opinions of patients and staff was made at times over a period of two years before and one year after the opening of an experimental surgery tmit specially designed for a particular way of organising the doctor/nurse team in general practice. The investigation took place in a busy group practice of three doctors caring between them for over 9000 patients living in a London borough

Media Downloading, Uploading, and Sharing Among College Students

On many occasions over recent years the Recording Industry Association of America (RIAA) has made national headlines with its large-scale effort to launch civil suits against individuals alleged to be involved in illegal downloading of copyrighted material over the Internet including many college students. By reputation, college students are among the most active users of digital media obtained through peer-to-peer downloading and similar techniques. We conducted a three-phase study to understand student beliefs and behavior in the areas of media downloading, copyright, intellectual property ownership, and computing security. The research included a small cohort of personal interviews, an anonymous paper and pencil survey of 164 students, and a Web-based survey with 402 respondents

Performance of a parallel code for the Euler equations on hypercube computers

The performance of hypercubes were evaluated on a computational fluid dynamics problem and the parallel environment issues were considered that must be addressed, such as algorithm changes, implementation choices, programming effort, and programming environment. The evaluation focuses on a widely used fluid dynamics code, FLO52, which solves the two dimensional steady Euler equations describing flow around the airfoil. The code development experience is described, including interacting with the operating system, utilizing the message-passing communication system, and code modifications necessary to increase parallel efficiency. Results from two hypercube parallel computers (a 16-node iPSC/2, and a 512-node NCUBE/ten) are discussed and compared. In addition, a mathematical model of the execution time was developed as a function of several machine and algorithm parameters. This model accurately predicts the actual run times obtained and is used to explore the performance of the code in interesting but yet physically realizable regions of the parameter space. Based on this model, predictions about future hypercubes are made

Equivalence Scales Based on Revealed Preference Consumption Expenditure Microdata - The Case of West Germany zu Lüneburg

Equivalence scales are a prerequisite for any economic well-being comparison with measures on income distribution, inequality and poverty. This paper provides equivalence scales based on revealed preference consumption microdata for West Germany 1983. It is a part of a joint US and German research project comparing equivalence scales with consistent methods and similar microdata bases, recent income and consumption surveys of both countries. We concentrate on a single equation expenditure method with different Engel approaches as well as on a complete demand system approach. The complete demand system approach provides true, constant utility based equivalence scales and is specified by an extended linear expenditure system (ELES). While the Engel methods traditionally focus on food expenditures, the multiple equation expenditure system takes into account a full market basket with all its interdependencies and relative prices. Our equivalence scale study for West Germany based on actual available individual consumption expenditure data shows a variety of interesting results with regard to different goods and services baskets as well as to different household composition effects including the situation of the elderly, of the families with married couples and single mothers, and the cost of children. Our consumption results finally are compared to further consumption, expert, and subjective based equivalence scales.alternative equivalence scales, Germany, USA, distribution of income, inequality, poverty

A study of the recommendations for disposition of cases discharged from the Bradley Home from January, 1952 to December, 1952.

Thesis (M.S.)--Boston Universit

Groundwater Irrigation System for Sustainable Agriculture

The aim of this project was to develop a prototype that may be a model to help relieve food insecurity in rural Liberia. This was accomplished by designing a groundwater extraction, recharge, and irrigation system to facilitate year-long crop-growth. The project was in partnership with BRAID Africa and a community in Zwedru, located in east Liberia, near the border of Côte D’Ivoire. During 2010 and 2011, a civil war broke out in Côte D’Ivoire and led to the citizens of the country taking refuge in Liberia (Leaf 2015). Many refugees have decided to stay in Liberia and are struggling to maintain food security as most subsist on rice with not even enough to sell. Currently, villagers in Zwedru only grow the rice in swamps during the rainy season and, with climate change, the rainy season is becoming increasingly unreliable (USAID 2012). The irrigation system that was designed for this project has allowed villagers to grow certain crops, such as cassava, okra, chard, and squash, during the dry season which will help alleviate food insecurity with the goal of providing a source of income for the farmers. This project was designed for a one hectare (2.47 acres) plot, which can be scaled up or down depending on land area and available resources

Recent Union Contract Concessions

macroeconomics, union concessions