Hampshire College

About: Hampshire College is a education organization based out in Amherst Center, Massachusetts, United States. It is known for research contribution in the topics: Genetic programming & Population. The organization has 461 authors who have published 998 publications receiving 40827 citations.

A behavior-based analysis of modal problems

Abstract: Genetic programming (GP) has proven to be a powerful tool for (semi)automated problem solving in various domains However, while the algorithmic aspects of GP have been a primary object of study, there is a need to enhance the understanding of the problems where GP is applied One particular goal is to categorize problems in a meaningful way, in order to select the best tools that can possibly be used to solve them This paper studies modal problems, a conceptual class of problems recently proposed by Spector at GECCO 2012 Modal problems are those for which a solution program requires different modes of operation for different contexts The thesis of this paper is that modality, in this sense, is better understood by analyzing program performance in behavioral space The behavior-based perspective is seen as part of a scale of different forms of analyzing performance; with a coarse view given by a global fitness value and a highly detailed view provided by the semantics approach On the other hand, behavioral analysis is seen as a flexible approach where the context of a program's performance is considered at in a domain-specific manner The experimental evidence presented here suggests that behavior-based search could allow a GP to find programs with disjoint behavioral structures, that can satisfy the requirements of each mode of operation of a modal problem

Evaluating Inquiry Learning Through Recognition-Based Tasks

Abstract: The Rashi inquiry learning environment for human biology was evaluated using a new instrument for assessing gains in scientific inquiry skills. The instrument was designed to be sensitive to the small pre-post skill gains that are hypothesized for short learning interventions. It is also designed to be scored with less effort than the verbal protocol analysis methods most often used to asses higher order skills. To achieve these ends the instrument is “item-based”, “recognition-based” and “difference-based.” We describe our assessment design method and results of its first use.

Superdense teleportation for space applications

Abstract: Establishing a quantum communication network would provide advantages in areas such as security and information processing. Such a network would require the implementation of quantum teleportation between remote parties. However, for photonic "qudits" of dimension greater than two, this teleportation always fails due to the inability to carry out the required quantum Bell-state measurement. A quantum communication protocol called Superdense Teleportation (SDT) can allow the reconstruction of a state without the usual 2-photon Bell-state measurements, enabling the protocol to succeed deterministically even for high dimensional qudits. This technique restricts the class of states transferred to equimodular states, a type of superposition state where each term can differ from the others in phase but not in amplitude; this restricted space of transmitted states allows the transfer to occur deterministically. We report on our implementation of SDT using photon pairs that are entangled in both polarization and temporal mode. After encoding the phases of the desired equimodular state on the signal photon, we perform a complete tomography on the idler photon to verify that we properly prepared the chosen state. Beyond our tabletop demonstration, we are working towards an implementation between a space platform in low earth orbit and a ground telescope, to demonstrate the feasibility of space-based quantum communication. We will discuss the various challenges presented by moving the experiment out of the laboratory, and our proposed solutions to make Superdense Teleportation realizable in the space setting.

Neo-Lamarckism and technique: Hans Spemann and the development of experimental embryology.

Abstract: Adherents of neo-Lamarckism in the early twentieth century are often viewed as a curiosity. Holding on to an outmoded philosophy, they seem less than fully scientific given the new experimental impulses in early twentieth-century biology.' However, it is often forgotten how widespread neo-Lamarckism was around 1900, and that neo-Lamarckians were by no means the underdogs in the battle with Weismannism at that time. The purpose of this paper is to examine the neo-Lamarckian context in which experimental work evolved in Germany in the early twentieth century.2 I will argue that the experimental program devised by Hans Spemann combined an increasingly highly prized technical virtuosity with a neo-Lamarckian view of nature. By examining the experimental program that Speman carried out and comparing it with the suggestions for such a program outlined by Spemann's friend and mentor, August Pauly, I shall try to display the assumptions that shaped Spemann's work.

Mass drivers. 1: Electrical design

Abstract: A mass driver is an electrical device used to accelerate payloads of any material to a high velocity. Small vehicles (called buckets) containing superconducting coils carry the payloads. These buckets are accelerated by pulsed magnetic fields, timed by information on their position, and are guided by induced magnetic fields set up in a surrounding guideway. Upon reaching the correct velocity, the buckets release their payloads, then they are slowed for recirculation to be reused. A rationale is presented that leads to a relatively simple and near-optimum design, as well as basic programs for calculating acceleration. The transverse oscillation frequencies are found to be invariant to guideway transverse dimensions.