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View 3: A Programming Environment For Distributed Programming, Ann Kratzer Jan 1986

View 3: A Programming Environment For Distributed Programming, Ann Kratzer

Computer Science Technical Reports

View 3 is an experimental programming environment to support the development and use of distributed programs. It builds upon three major concepts. First, distributed programs and distributed processes are basic objects. Second, the port mechanism allows a process to exchange information with another process, a file or an I/O device without concern for the type of the object on the other end of the port. Third, test and use of distributed programs are facilitated by the user interface program screen format that allows the user to control both the format and contents of the physical terminal.

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Producing Software Using Tools In A Workstation Environment, Mark Sherman, Robert L. Scot Drysdale Jan 1986

Producing Software Using Tools In A Workstation Environment, Mark Sherman, Robert L. Scot Drysdale

Computer Science Technical Reports

We discuss how we taught students to build and use translation, interpretive, editing and monitoring tools in an undergraduate software engineering course. Students used the tools on low-cost workstations (Macintoshes) to build large, group projects. The students' projects used all available features of workstation environments, including graphics, windows, fonts, mice, networks, and sound generators. We found that 1) the use of tools increased student productivity, 2) a shift in a data structure and algorithm topics is needed to cover material relevant for workstation environments, 3) new topics in system design are required for a workstation environment, 4) traditional material can …

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An Algorithm For Resource Allocation Requiring Low Overhead Communication, Ann Marks Jan 1986

An Algorithm For Resource Allocation Requiring Low Overhead Communication, Ann Marks

Computer Science Technical Reports

A heuristic algorithm for allocating resource units to sites in a distributed system is presented. Starting with a given allocation of sites, the algorithm performs a series of optimizations involving pairs of sites in an attempt to improve the worst pair-wise imbalance present in the system; termination occurs when no further improvement is possible. After outlining the general form of the algorithm, which effectively defines an entire family of algorithms, we present theoretical results that speak to the performance of the algorithm as measured in the number of optimizations that can be done, the amount of control communication required and …

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Using Low-Cost Workstations To Investigate Computer Networks And Distributed Systems, Mark Sherman, Ann Marks Jan 1986

Using Low-Cost Workstations To Investigate Computer Networks And Distributed Systems, Mark Sherman, Ann Marks

Computer Science Technical Reports

A quality education in contemporary computer science requires that students gain experience with realistic systems. Many efforts at bringing empirical computer science to undergraduates focus on rather old technologies, for example, building a compiler or simulating a disk scheduler. Although efforts are being made to use some newer technologies, the efforts are concentrating on teaching traditional material in a new medium. However, the medium itself -- networked workstations in a server environment -- is worthy of exploration by undergraduate students in a laboratory setting. At Dartmouth, we developed a Computer Network Laboratory to let students experiment with computer networks, protocols …

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A Network Package For The Macintosh Using The Dod Internet Protocols, Mark Sherman Jan 1986

A Network Package For The Macintosh Using The Dod Internet Protocols, Mark Sherman

Computer Science Technical Reports

This memo describes the design, implementation and use of the MacIP libraries and programs for running DoD Internet Protocols on the Macintosh over Apple Talk. It is preliminary documentation and out of date, but it is all that exists.

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Bruce: A Graphics System With Hidden Line And Hidden Surface Algorithms, Keith Vetter, Christopher Roche May 1985

Bruce: A Graphics System With Hidden Line And Hidden Surface Algorithms, Keith Vetter, Christopher Roche

Computer Science Technical Reports

Accurately representing the physical world by computer is a topic which has direct benefits to fields like chemistry and architecture, and is a source of much research in computer science. This paper examines the steps necessary to develop and implement a graphical system that will allow for the modeling of physical world objects. In particular, this is a description of BRUCE: a graphical system that will describe a world of three dimensional polyhedra, implementing algorithms for hidden line and hidden surface removal. This paper also deals with the problems incurred along the way and suggestions for further improvement of BRUCE.

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Creating Havoc: Havoc Development Program, David Cohn, Stephen Madancy Jan 1985

Creating Havoc: Havoc Development Program, David Cohn, Stephen Madancy

Dartmouth College Undergraduate Theses

One area where use of the computer is essential is in the modern scientific laboratory. High speed computation, data storage and data analysis enable scientists to perform experiments that would otherwise be impractical. A problem inherent to the effective use of special purpose laboratory computers, however, is the fact that this equipment has generally been developed for highly specific uses, and has either tried to cope with existing high-level languages or has abandoned the attempt and required the user to program in a low-level assembly or machine language. Our idea was to design, develop and implement a programming language that …

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Dartmouth-Smalltalk: An Exercise In Implementation, Joon Sup Lee Jun 1984

Dartmouth-Smalltalk: An Exercise In Implementation, Joon Sup Lee

Computer Science Technical Reports

This report discusses a preliminary implementation of the Smalltalk-80 virtual machine for Vax/Unix.

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An Image Processing Software Package For The Laser Scanning Phase Modulation Microscope, William J. Murray Jun 1984

An Image Processing Software Package For The Laser Scanning Phase Modulation Microscope, William J. Murray

Computer Science Technical Reports

This thesis documents the most recent effort to develop a user-friendly image processing software package for the Laser Scanning Phase Modulation Microscope (LSPMM). The LSPMM is composed of three integrated subsystems, the Laser Scanning (LS) system, the Phase Modulation (PM) system, and Digital Image Acquisition (DIA) system. Under the control of the image processing software, the DIA system can receive and store the digital image data, display the image on a monochrome monitor, and process the image to provide the microscopist with quantitative information regarding the image. The implementation of this image processing software package required the specification of a …

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Spectroscopic Studies Of 4u1735 – 44; Evidence For Binary Motion, A. P. Smale, P. A. Charles, I. R. Tuohy, J. R. Thorstensen Mar 1984

Spectroscopic Studies Of 4u1735 – 44; Evidence For Binary Motion, A. P. Smale, P. A. Charles, I. R. Tuohy, J. R. Thorstensen

Dartmouth Scholarship

We have obtained optical spectroscopy of the X-ray burst source 4U1735 – 44 with spectral resolution of ∼ 1.6 Å and a time resolution of ∼ 30 min. There is strong evidence for cyclic He II velocity variations, but we are unable to confirm or deny either of the previously reported possible binary periodicities in the source. However, kinematic arguments suggest that the companion can be classified as being of spectral type F0–K5 V and the presence of the Ca II K interstellar absorption line at λ 3933 leads to a lower limit on the distance of the source of …

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View-3 And Ada: Tools For Building Systems With Many Tasks, Ann Kratzer, Mark Sherman Mar 1984

View-3 And Ada: Tools For Building Systems With Many Tasks, Ann Kratzer, Mark Sherman

Dartmouth Scholarship

This paper discusses some useful features for tools that are intended to be used for developing systems with multiple tasks. We include a description of one tool that has been built, View-3. We also describe some problems that might be encountered when trying to fit this kind of tool into an APSE system.

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Photometric And Spectroscopic Observations Of An Optical Candidate For The X-Ray Source H 0544 - 665, M. Van Der Klis, J. Van Paradijs, P. A. Charles, J. R. Thorstensen Jun 1983

Photometric And Spectroscopic Observations Of An Optical Candidate For The X-Ray Source H 0544 - 665, M. Van Der Klis, J. Van Paradijs, P. A. Charles, J. R. Thorstensen

Dartmouth Scholarship

We present the results of spectroscopic and UBV observations of the brightest star in the error box of the X-ray source H 0544–665. This object is a B0–1 V star and a member of the LMC. It shows correlated variations in brightness and colour indices. We suggest that it is a Be-type star observed during a stage of low emission strength. Although a relation between this star and the X-ray source has still to be proven the present data add considerable support to the proposed identification.

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Extreme Variability In The Be-Type, Periodic Recurrent X-Ray Transient A0538 - 66: A Highly Eccentric Interacting Binary, P. A. Charles, L. Booth, R. H. Densham, G. T. Bath, J. R. Thorstensen Mar 1983

Extreme Variability In The Be-Type, Periodic Recurrent X-Ray Transient A0538 - 66: A Highly Eccentric Interacting Binary, P. A. Charles, L. Booth, R. H. Densham, G. T. Bath, J. R. Thorstensen

Dartmouth Scholarship

We present optical spectroscopy and photometry and IUE spectroscopy of the counterpart of the extremely powerful LMC recurrent X-ray transient A0538 – 66. During one 16.6 day outburst cycle at the end of 1980 December the optical spectra show steadily increasing Balmer and He I emission (indicative of an expanding envelope) superposed on a B2 III–IV spectrum. There is a substantial optical brightness increase of 2 mag at the peak, accompanied by the sudden turn-on of He IIλ 4686. These and other optical spectra show significant radial velocity changes but we can find no clear correlation with the 16.6 …

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Spermidine-Condensed Phi X174 Dna Cleavage By Micrococcal Nuclease: Torus Cleavage Model And Evidence For Unidirectional Circumferential Dna Wrapping., Kenneth A. Marx, Thomas C. Reynolds Nov 1982

Spermidine-Condensed Phi X174 Dna Cleavage By Micrococcal Nuclease: Torus Cleavage Model And Evidence For Unidirectional Circumferential Dna Wrapping., Kenneth A. Marx, Thomas C. Reynolds

Dartmouth Scholarship

Spermidine-condensed phi X174 replicative form (RF) II DNA was digested with micrococcal nuclease to yield seven identifiable DNA bands forming an arithmetic fragment-length series. The DNA monomer unit length was found to be 780 +/- 80 base pairs. This result is most consistent with a proposed model for micrococcal nuclease cleavage of a DNA torus organized by the unidirectional, circumferential wrapping of B-geometry DNA. By a topological consideration, the blunt-end-rod-fusion model for torus formation [Eickbush, T. H. & Moudrianakis, E. N. (1978) Cell 13, 295-306] is shown to be inconsistent with our empirical solution results. We propose a continuous, circumferential …

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Excluded-Volume Effect On Quasi-Elastic Light Scattering By Flexible Macromolecules, Genzo Tanaka, Walter H. Stockmayer Oct 1982

Excluded-Volume Effect On Quasi-Elastic Light Scattering By Flexible Macromolecules, Genzo Tanaka, Walter H. Stockmayer

Dartmouth Scholarship

First-order perturbation expressions are developed for the first cumulant (initial time derivative) of the dynamic structure factor observable by photon-correlation measurements of the light scattered by flexible chain molecules in solution. A dimensionless coefficient C, which measures the initial departure of the first cumulant from proportionality to the square of the scattering vector, is found to be only slightly altered by excluded-volume effects.

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A Classification Of Certain Graphs With Minimal Imperfection Properties, S. H. Whitesides Jan 1982

A Classification Of Certain Graphs With Minimal Imperfection Properties, S. H. Whitesides

Dartmouth Scholarship

The family of (α, ω) graphs are of interest for several reasons. For example, any minimal counter-example to Berge's Strong Perfect Graph Conjecture belongs to this family. This paper accounts for all (4, 3) graphs. One of these is not obtainable by existing techniques for generating (α + 1, ω) graphs from (α, ω) graphs.

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The Role Of Metals In Carcinogenesis: Biochemistry And Metabolism, K Wetterhahn Jennette Aug 1981

The Role Of Metals In Carcinogenesis: Biochemistry And Metabolism, K Wetterhahn Jennette

Dartmouth Scholarship

The oxyanions of vanadium, chromium, molybdenum, arsenic, and selenium are stable forms of these elements in high oxidation states which cross cell membranes using the normal phosphate and/or sulfate transport systems of the cell. Once inside the cell, these oxyanions may sulfuryl transfer reactions. Often the oxyanions serve as alternate enzyme substrates but form ester products which are hydrolytically unstable compared with the sulfate and phosphate esters and, therefore, decompose readily in aqueous solution. Arsenite and selenite are capable of reacting with sulfhydryl groups in proteins. Some cells are able to metabolize redox active oxyanions to forms of the elements …

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Incidence Codes Of Posets: Eulerian Posets And Reed-Muller Codes, Kenneth P. Bogart Jan 1980

Incidence Codes Of Posets: Eulerian Posets And Reed-Muller Codes, Kenneth P. Bogart

Dartmouth Scholarship

This paper shows how to construct analogs of Reed-Muller codes from partially ordered sets. In the case that the partially ordered set is Eulerian the length of the code is the number of elements in the poset, the dimension is the size of a selected order ideal and the minimum distance is the minimum size of a principal dual ideal generated by a member of the order ideal. In this case, the majority logic method of decoding Reed-Muller codes works for incidence codes. A number of interesting combinatorial questions arise from the study of these codes.

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