Experiments in apply morphological analysis in speech recognition and their cognitive explanation

May 200

An analysis of spacecraft data time tagging errors

An indepth examination of the timing and telemetry in just one spacecraft points out the genesis of various types of timing errors and serves as a guide in the design of future timing/telemetry systems. The principal sources of timing errors are examined carefully and are described in detail. Estimates of these errors are also made and presented. It is found that the timing errors within the telemetry system are larger than the total timing errors resulting from all other sources

Social Structure and Opinion Formation

We present a dynamical theory of opinion formation that takes explicitly into account the structure of the social network in which in- dividuals are embedded. The theory predicts the evolution of a set of opinions through the social network and establishes the existence of a martingale property, i.e. that the expected weighted fraction of the population that holds a given opinion is constant in time. Most importantly, this weighted fraction is not either zero or one, but corresponds to a non-trivial distribution of opinions in the long time limit. This co-existence of opinions within a social network is in agreement with the often observed locality effect, in which an opinion or a fad is localized to given groups without infecting the whole society. We verified these predictions, as well as those concerning the fragility of opinions and the importance of highly connected individuals in opinion formation, by performing computer experiments on a number of social networks

Bootstrapping the Long Tail in Peer to Peer Systems

We describe an efficient incentive mechanism for P2P systems that generates a wide diversity of content offerings while responding adaptively to customer demand. Files are served and paid for through a parimutuel market similar to that commonly used for betting in horse races. An analysis of the performance of such a system shows that there exists an equilibrium with a long tail in the distribution of content offerings, which guarantees the real time provision of any content regardless of its popularity

Dust Evolution and the Formation of Planetesimals

The solid content of circumstellar disks is inherited from the interstellar medium: dust particles of at most a micrometer in size. Protoplanetary disks are the environment where these dust grains need to grow at least 13 orders of magnitude in size. Our understanding of this growth process is far from complete, with different physics seemingly posing obstacles to this growth at various stages. Yet, the ubiquity of planets in our galaxy suggests that planet formation is a robust mechanism. This chapter focuses on the earliest stages of planet formation, the growth of small dust grains towards the gravitationally bound "planetesimals", the building blocks of planets. We will introduce some of the key physics involved in the growth processes and discuss how they are expected to shape the global behavior of the solid content of disks. We will consider possible pathways towards the formation of larger bodies and conclude by reviewing some of the recent observational advances in the field.Comment: 43 pages, 6 figures. Chapter in International Space Science Institute (ISSI) Book on "The Disk in Relation to the Formation of Planets and their Proto-atmospheres", published in Space Science Reviews by Springe

Maximising utility savings through appropriate implementation of combined heat and power scheme

Combined Heat And Power (CHP) Scheme, Also Known As Cogeneration Is Widely Accepted As A Highly Efficient Energy Saving Measure, Particularly In Medium To Large Scale Chemical Process Plants. The Advantages Of A CHP Scheme For A Chemical Plant Are Two-Fold: (I) To Drastically Reduce Electricity Bill From On-Site Power Generation (Ii) To Save On Fuel Bills Through Recovery Of The Quality Waste Heat From Power Generation For Process Heating. In Order To Be Effective, A CHP Scheme Must Be Placed At The Right Temperature Level, In The Context Of An Overall Process System. Failure To Do So Might Render A CHP Venture Worthless. This Paper Describes The Procedure For An Effective Implementation Of A CHP Scheme Using An Ethyl Benzene Process As A Case Study. A Key Visualisation Tool In Pinch Analysis Technique Known As The Grand Composite Curve Is Used To Guide CHP Integration, And Allows It To Be Optimally Placed Within The Overall Process Scenario. The Study Shows That Appropriate CHP Integration With The Ethyl Benzene Process Above The Pinch Can Potentially Result In Significant Savings On Electricity Cost Of Up To 87%