Role-playing in the elementary school

Thesis (Ed. M.)--Boston University, 1963. Includes bibliographical references (leaves 73-74

Economic Impacts of Establishing Short Rotation Woody Crops to Support Energy Production in Minnesota

The utilization of short rotation woody crops (SRWC) to produce wood on marginal crop and pasture land could greatly enhance the production of wood for various uses in Minnesota with utilization for energy being of current interest. SRWC involves the more intensive application of inputs on more valuable land than naturally regenerated forests that currently supply the bulk of the forest products industry in Minnesota. Breeding efforts to improve productivity and disease resistance in hybrid poplar species are making the technology of SRWC competitive with agricultural uses of marginal land. This study models the economic impact of a potential shift in use of the land resource by replacing production of hay and pasture that provides feed for cow-calf beef operations in northwest and west central Minnesota with SRWC. Regional economic impacts of such a shift are measured with established input-output techniques, using the software tool IMPLAN. To complete this analysis, the magnitudes and sectors of expenditures needed to produce either beef calves or hybrid poplar plantations were compared using farm records and hybrid poplar budgets. Construction of a $175 million energy conversion facility capable of making 44 million gallons of ethanol and 7.6 million gallons of mixed alcohols by catalytic means following gasification would result in creation of 2,412 jobs during the construction period, with$158 million in value-added (mainly employee compensation and business taxes). Operation of the facility after the end of construction, if supported by 200,000 acres of hybrid poplar production, would not change the number of jobs very much compared with using the land for cow-calf operations. However, the SRWC-related jobs would likely be at higher average salary levels and business tax collections would be higher, for a value-added increase of $80 million annually. In addition to greater wood supplies to support the forest products industry, logging pressures may be reduced on public forest land as a consequence of greater deployment of technology and methods that can result in production per acre that is eight to ten-fold greater than naturally regenerated forests.Hybrid Poplar, SRWC, IMPLAN, economics, energy, ethanol, OSB, Resource /Energy Economics and Policy,

Three-meter balloon-borne telescope

The Three-Meter Balloon-Borne Telescope is planned as a general purpose facility for making far-infrared and submillimeter astronomical observations from the stratosphere. It will operate throughout the spectral range 30 microns to 1 millimeter which is largely obscurred from the ground. The design is an f/13.5 Cassegrain telescope with an f/1.33 3-meter primary mirror supported with a 3-axis gimbal and stabilization system. The overall structure is 8.0 m high by 5.5 m in width by 4.0 m in depth and weighs 2000 kg. This low weight is achieved through the use of an ultra lightweight primary mirror of composite construction. Pointing and stabilization are achieved with television monitoring of the star field, flex-pivot bearing supports, gyroscopes, and magnetically levitated reaction wheels. Two instruments will be carried on each flight; generally a photometric camera and a spectrometer. A 64-element bolometer array photometric camera operating from 30 to 300 microns is planned as part of the facility. Additional instruments will be derived from KAO and other development programs

AN EXAMINATION OF A DEVELOPMENT RIGHTS PURCHASE PROGRAM FOR ALASKA AGRICULTURAL LANDS

A report submitted to the Department of Natural Resources, State of Alaska, in accordance with terms of research contract OCTO 1142.Many Alaskans are concerned about the conversion of highly productive agricultural lands to nonagricultural uses now occurring in the state. Land on the urban fringes of Anchorage and Fairbanks that once produced vegetables and grains or supported dairy farms appears most vulnerable to this conversion. As major population centers grow, residential, shopping center and industrial land uses displace agriculture because they render greater returns. This displacement is viewed by some as not being in society's best interest. Those concerned about the loss of agricultural lands argue that these lands are some of the best agricultural lands in the state and are vital to maintaining the agricultural economy of the state. In addition, it is suggested that their preservation will help to maintain a much desired way of life and to provide needed open space. The state and municipal governments in Alaska have made attempts to intervene in the land market to slow down or stop agricultural land conversion. Methods employed to date include tax incentives and the sale of only the agricultural rights on state or municipal lands. This report discusses the feasibility of an alternative means of preserving agricultural lands, namely, the public purchase of development rights from private landowners. Under this voluntary arrangement, private agricultural landowners would be compensated for giving up their option to develop their land for nonagricultural purposes.Introduction: Overview, Plan of Report -- Market Failure and the Allocation of Agricultural Land Resources -- Agricultural Land Conversion in Alaska -- Present and Potential Agricultural Development in Alaska: Introduction, Present Agricultural Situation, Agricultural Lands for Future Development, Future Agricultural Development in Alaska -- Purchase of Development Rights: Suffolk County: History, Maryland, New Jersey, Massachusetts and Connecticut, Definition of Development Rights, Strengths and Weaknesses of Development Rights Purchases -- Applicability of a Development Rights Program in Alaska: Introduction, Development Rights Survey in Alaska: Response, Farm Size of Respondents, Interest in Selling Development Rights, Market Values of Cleared and Uncleared Agricultural Lands, Value of Development Rights, Distance from a Population Center, Interest in Selling Development Rights, and Perceived Value of Development Rights -- Economic Size Agricultural Operations -- Potential Costs of a Purchase of Development Rights Program: Other Costs -- Benefits of Development Rights Acquisition: Maintenance of the Local Agricultural Economy, Locally Produced Food, Open Space and Other Public Good Amenities, Removal of Uncertainty -- Other Agricultural Land Control Tools: Comparison of Agricultural Land Preservation Tools -- Summary and Conclusions -- References -- Appendix A: Operation of of Purchase of Development Rights Programs -- Appendix B: Alaska Agricultural Lands Survey -- Appendix C: Additional Comments from Respondents -- Appendix D: Alternative Agricultural Land Control Technique

Levels or Differences in Meat Demand Specification

We estimated a wholesale demand system for beef, pork, lamb, chicken, and turkey using quarterly U.S. data and a dynamic, CBS system (Keller and Van Driel). The CBS system is a differential system, which means that it might be more appropriately applied in those situations where the data have unit roots. If there are unit roots, differencing the data can improve the properties of the estimates. If the data do not have unit roots, differencing the data might harm the properties of the estimates. We tested the specification of the model's error terms using state-space techniques. State-space units allow one to deal with roots on the unit circle without filtering the data (See Durbin and Koopman). The demand system has only four independent error terms. The state-space model we used could have decomposed these four independent error terms into four errors with unit roots and four with 0 roots. Adding state-space features to the model greatly improved its performance as measured by the likelihood ratio statistics. The estimates imply that the raw demand data have two unit roots and three 0 roots. Our mixed approach improves the properties of the estimates.Demand and Price Analysis,

Quantum Channels and Representation Theory

In the study of d-dimensional quantum channels $(d \geq 2)$, an assumption which is not very restrictive, and which has a natural physical interpretation, is that the corresponding Kraus operators form a representation of a Lie algebra. Physically, this is a symmetry algebra for the interaction Hamiltonian. This paper begins a systematic study of channels defined by representations; the famous Werner-Holevo channel is one element of this infinite class. We show that the channel derived from the defining representation of SU(n) is a depolarizing channel for all $n$, but for most other representations this is not the case. Since the Bloch sphere is not appropriate here, we develop technology which is a generalization of Bloch's technique. Our method works by representing the density matrix as a polynomial in symmetrized products of Lie algebra generators, with coefficients that are symmetric tensors. Using these tensor methods we prove eleven theorems, derive many explicit formulas and show other interesting properties of quantum channels in various dimensions, with various Lie symmetry algebras. We also derive numerical estimates on the size of a generalized ``Bloch sphere'' for certain channels. There remain many open questions which are indicated at various points through the paper.Comment: 28 pages, 1 figur

The Impact of Domestic and Import Prices on U.S. Lamb Imports: A Production System Approach

As U.S. lamb imports increased relative to domestic production, and the relative share of chilled to frozen lamb imports increased, importers of chilled lamb have become less responsive to domestic and import prices, while the direct opposite is the case for frozen lamb imports. From 1990 to 2003, chilled lamb imports from Australia and New Zealand became less and less responsive to U.S. prices, and frozen imports became more responsive. Unconditional own-price elasticities also show that, over time, imports of chilled lamb became less responsive to import prices while frozen imports became more responsive to import prices.lamb, demand, imports, trade, import demand, production, International Relations/Trade,

U.S. DEMAND FOR IMPORTED LAMB BY COUNTRY: A TWO-STAGE DIFFERENTIAL PRODUCTION APPROACH

Due to a depressed wool industry sheep inventories have been declining resulting in significant increases in lamb and mutton imports. Goals of this paper are to estimate the derived demand and output supply for U.S. lamb imports, estimate demand elasticities, and to determine the impact of TRQ reductions on imports.Demand and Price Analysis,