3,181 research outputs found
Anaerobic co-digestion of acetate-rich with lignin-rich wastewater and the effect of hydrotalcite addition
The methane potential and biodegradability of different ratios of acetate and lignin-rich effluents from a neutral sulfite semi-chemical (NSSC) pulp mill were investigated. Results showed ultimate methane yields up to 333 ± 5 mL CH4/gCOD when only acetate-rich substrate was added and subsequently lower methane potentials of 192 ± 4 mL CH4/gCOD when the lignin fraction was increased. The presence of lignin showed a linear decay in methane production, resulting in a 41% decrease in methane when the lignin-rich feed had a 30% increase. A negative linear correlation between lignin content and biodegradability was also observed. Furthermore, the effect of hydrotalcite (HT) addition was evaluated and showed increase in methane potential of up to 8%, a faster production rate and higher soluble lignin removal (7–12% higher). Chemical oxygen demand (COD) removal efficiencies between 64 and 83% were obtained for all samples.Peer ReviewedPostprint (author's final draft
NASA software specification and evaluation system design
The Software Specification and Evaluation System (SSES) manager's guide is presented along with the NSSC-2 computer brochure. Development, evaluation, and modification of the SSES are summarized
Childhood and the politics of scale: Descaling children's geographies?
This is the post-print version of the final published paper that is available from the link below. Copyright @ 2008 SAGE Publications.The past decade has witnessed a resurgence of interest in the geographies of children's lives, and particularly in engaging the voices and activities of young people in geographical research. Much of this growing body of scholarship is characterized by a very parochial locus of interest — the neighbourhood, playground, shopping mall or journey to school. In this paper I explore some of the roots of children's geographies' preoccupation with the micro-scale and argue that it limits the relevance of research, both politically and to other areas of geography. In order to widen the scope of children's geographies, some scholars have engaged with developments in the theorization of scale. I present these arguments but also point to their limitations. As an alternative, I propose that the notion of a flat ontology might help overcome some difficulties around scalar thinking, and provide a useful means of conceptualizing sociospatiality in material and non-hierarchical terms. Bringing together flat ontology and work in children's geographies on embodied subjectivity, I argue that it is important to examine the nature and limits of children's spaces of perception and action. While these spaces are not simply `local', they seldom afford children opportunities to comment on, or intervene in, the events, processes and decisions that shape their own lives. The implications for the substance and method of children's geographies and for geographical work on scale are considered
NSSC-2 operating system design requirements specification
The design requirements and implementation standards for an NSSC-2 operating system are defined. An operating system diagram is presented along with system concepts and terminology
Interpretive computer simulator for the NASA Standard Spacecraft Computer-2 (NSSC-2)
An Interpretive Computer Simulator (ICS) for the NASA Standard Spacecraft Computer-II (NSSC-II) was developed as a code verification and testing tool for the Annular Suspension and Pointing System (ASPS) project. The simulator is written in the higher level language PASCAL and implented on the CDC CYBER series computer system. It is supported by a metal assembler, a linkage loader for the NSSC-II, and a utility library to meet the application requirements. The architectural design of the NSSC-II is that of an IBM System/360 (S/360) and supports all but four instructions of the S/360 standard instruction set. The structural design of the ICS is described with emphasis on the design differences between it and the NSSC-II hardware. The program flow is diagrammed, with the function of each procedure being defined; the instruction implementation is discussed in broad terms; and the instruction timings used in the ICS are listed. An example of the steps required to process an assembly level language program on the ICS is included. The example illustrates the control cards necessary to assemble, load, and execute assembly language code; the sample program to to be executed; the executable load module produced by the loader; and the resulting output produced by the ICS
Determination of Chemical Composition of Wood Pulp Hydrolyzates by Paper Chromatography
The available literature on paper chromatography was surveyed. Special attention was given to those techniques dealing with the analysis of wood pulp hydrolyzates. Five hardwood pulp hydrolyzates were analyzed by paper chromatographic means. All hardwood pulp hydrolyzates analyzed tended to fall in a relatively narrow range of chemical composition. Glucose and xylose were found to be the main constituents with traces of mannose and galactose present in some pulp hydrolyzates
A translator writing system for microcomputer high-level languages and assemblers
In order to implement high level languages whenever possible, a translator writing system of advanced design was developed. It is intended for routine production use by many programmers working on different projects. As well as a fairly conventional parser generator, it includes a system for the rapid generation of table driven code generators. The parser generator was developed from a prototype version. The translator writing system includes various tools for the management of the source text of a compiler under construction. In addition, it supplies various default source code sections so that its output is always compilable and executable. The system thereby encourages iterative enhancement as a development methodology by ensuring an executable program from the earliest stages of a compiler development project. The translator writing system includes PASCAL/48 compiler, three assemblers, and two compilers for a subset of HAL/S
Sizing and Energy Management of a Hybrid Locomotive Based on Flywheel and Accumulators
The French National Railways Company (SNCF) is interested in the design of a hybrid locomotive based on various storage devices (accumulator, flywheel, and ultracapacitor) and fed by a diesel generator. This paper particularly deals with the integration of a flywheel device as a storage element with a reduced-power diesel generator and accumulators on the hybrid locomotive. First, a power flow model of energy-storage elements (flywheel and accumulator) is developed to achieve the design of the whole traction system. Then, two energy-management strategies based on a frequency approach are proposed. The first strategy led us to a bad exploitation of the flywheel, whereas the second strategy provides an optimal sizing of the storage device. Finally, a comparative study of the proposed structure with a flywheel and the existing structure of the locomotive (diesel generator, accumulators, and ultracapacitors) is presented
Natural relations among physical observables in the neutrino mass matrix
We find all possible relations among physical observables arising from
neutrino mass matrices that describe in a natural way the currently observed
pattern (tan_23 and tan_12 large, dm^2_Sun/dm^2_Atm and tan_13 small) in terms
of a minimum number of parameters. Natural here means due only to the relative
smallness (vanishing) of some parameters in the relevant lagrangian, without
special relations or accidental cancellations among them.Comment: 14 pages, 1 eps figur
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