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The analysis of scenarios in which a number of microphones record the activity of speakers, such as in a round-table meeting, presents a number of computational challenges. For example, if each participant wears a microphone, speech from both the microphone's wearer (local speech) and from other participants (crosstalk) is received. The recorded audio can be broadly classified in four ways: local speech, crosstalk plus local speech, crosstalk alone and silence. We describe two experiments related to the automatic classification of audio into these four classes. The first experiment attempted to optimize a set of acoustic features for use with a Gaussian mixture model (GMM) classifier. A large set of potential acoustic features were considered, some of which have been employed in previous studies. The best-performing features were found to be kurtosis, "fundamentalness," and cross-correlation metrics. The second experiment used these features to train an ergodic hidden Markov model classifier. Tests performed on a large corpus of recorded meetings show classification accuracies of up to 96%, and automatic speech recognition performance close to that obtained using ground truth segmentation.

This article reports on a recent survey of community economic development (CED) professionals in Utah. The survey was conducted in two stages. In the first, a questionnaire was mailed to 113 officials in development or development-related departments in state, county, city, and quasigovernmental agencies throughout the state. Then, a follow-up in-depth telephone interview was conducted with a subset of this group. The project was motivated by a dearth of published information on development policy and the use of various development tools in the area and the perceived strengths or weaknesses of these tools. The research objectives were to elicit information about three components of local development efforts, including perceptions about the effectiveness of various development tools and the identification of factors that have contributed to strength or weakness in the local economy, and to assess the success of differential strategies for development. Emphasis was given to the differential ratings of tools and programs by officials in large urban areas and those in smaller cities. Not surprisingly, those in the larger areas (where growth has been especially rapid in recent years) view their efforts as having been quite successful; those in the smaller urban and rural areas indicated mixed results. The article is organized as follows: In the next section, information on Utah’s socioeconomic environment is provided as background or context for the survey results. The design of the written survey is described in the following section, which is followed by a discussion of the results. Next, the important findings from the telephone survey are reviewed. We conclude with a summary of key findings.

Recent work on searching the Semantic Web has yielded a wide range of approaches with respect to the style of input, the underlying search mechanisms and the manner in which results are presented. Each approach has an impact upon the quality of the information retrieved and the user’s experience of the search process. This highlights the need for formalised and consistent evaluation to benchmark the coverage, applicability and usability of existing tools and provide indications of future directions for advancement of the state-of-the-art. In this paper, we describe a comprehensive evaluation methodology which addresses both the underlying performance and the subjective usability of a tool. We present the key outcomes of a recently completed international evaluation campaign which adopted this approach and thus identify a number of new requirements for semantic search tools from both the perspective of the underlying technology as well as the user experience.

This paper describes the main goals and outcomes of the EU-funded Framework 7 project entitled Semantic Evaluation at Large Scale (SEALS). The growth and success of the Semantic Web is built upon a wide range of Semantic technologies from ontology engineering tools through to semantic web service discovery and semantic search. The evaluation of such technologies - and, indeed, assessments of their mutual compatibility - is critical for their sustained improvement and adoption. The SEALS project is creating an open and sustainable platform on which all aspects of an evaluation can be hosted and executed and has been designed to accommodate most technology types. It is envisaged that the platform will become the de facto repository of test datasets and will allow anyone to organise, execute and store the results of technology evaluations free of charge and without corporate bias. The demonstration will show how individual tools can be prepared for evaluation, uploaded to the platform, evaluated according to some criteria and the subsequent results viewed. In addition, the demonstration will show the flexibility and power of the SEALS Platform for evaluation organisers by highlighting some of the key technologies used.

Usability and user satisfaction are of paramount importance when designing interactive software solutions. Furthermore, the optimal design can be dependent not only on the task but also on the type of user. Evaluations can shed light on these issues; however, very few studies have focused on assessing the usability of semantic search systems. As semantic search becomes mainstream, there is growing need for standardised, comprehensive evaluation frameworks. In this study, we assess the usability and user satisfaction of different semantic search query input approaches (natural language and view-based) from the perspective of different user types (experts and casuals). Contrary to previous studies, we found that casual users preferred the form-based query approach whereas expert users found the graph-based to be the most intuitive. Additionally, the controlled-language model offered the most support for casual users but was perceived as restrictive by experts, thus limiting their ability to express their information needs.

nixon2011a; International audience; This paper describes the first five SEALS Evaluation Campaigns over the semantic technologies covered by the SEALS project (ontology engineering tools, ontology reasoning tools, ontology matching tools, semantic search tools, and semantic web service tools). It presents the evaluations and test data used in these campaigns and the tools that participated in them along with a comparative analysis of their results. It also presents some lessons learnt after the execution of the evaluation campaigns and draws some final conclusions.

The main problem with the state of the art in the semantic search domain is the lack of comprehensive evaluations. There exist only a few efforts to evaluate semantic search tools and to compare the results with other evaluations of their kind.In this paper, we present a systematic approach for testing and benchmarking semantic search tools that was developed within the SEALS project. Unlike other semantic web evaluations our methodology tests search tools both automatically and interactively with a human user in the loop. This allows us to test not only functional performance measures, such as precision and recall, but also usability issues, such as ease of use and comprehensibility of the query language.The paper describes the evaluation goals and assumptions; the criteria and metrics; the type of experiments we will conduct as well as the datasets required to conduct the evaluation in the context of the SEALS initiative. To our knowledge it is the first effort to present a comprehensive evaluation methodology for Semantic Web search tools.

Sound source localisation cues are severely degraded when multiple acoustic sources are active in the presence of reverberation. We present a binaural system for localising simultaneous speakers which exploits the fact that in a speech mixture there exist spectro-temporal regions or ‘fragments’, where the energy is dominated by just one of the speakers. A fragment-level localisation model is proposed that integrates the localisation cues within a fragment using a weighted mean. The weights are based on local estimates of the degree of reverberation in a given spectro-temporal cell. The paper investigates different weight estimation approaches based variously on, i) an established model of the perceptual precedence effect; ii) a measure of interaural coherence between the left and right ear signals; iii) a data-driven approach trained in matched acoustic conditions. Experiments with reverberant binaural data with two simultaneous speakers show appropriate weighting can improve frame-based localisation performance by up to 24%.

Teleconference participants often multitask: they work on a text-based ‘foreground’ task whilst listening in the ‘background’ for an item of interest to appear. Audio material should therefore be presented in a manner that has the smallest possible impact on the foreground task without affecting topic detection. Here, we ask whether dichotic or spatialised audio presentation of a meeting is less disruptive than the single-channel mixture of talkers normally used in teleconference audio. A number of talker location configurations are used, and we examine how these impact upon a text-based foreground task: finding all letter ‘e’ occurrences in a block of text. Additionally, we examine the effect of cueing the listener to direction or gender and record listener preferences for audio presentation style. Our results suggest that spatialised audio disrupts the foreground task less than single-channel audio when direction or gender is cued.

A speech separation system is described in which sources are represented in a joint interaural time difference-fundamental frequency (ITD-F0) cue space. Traditionally, recurrent timing neural networks (RTNNs) have been used only to extract periodicity information; in this study, this type of network is extended in two ways. Firstly, a coincidence detector layer is introduced, each node of which is tuned to a particular ITD; secondly, the RTNN is extended to become two-dimensional to allow periodicity analysis to be performed at each best-ITD. Thus, one axis of the RTNN represents F0 and the other ITD allowing sources to be segregated on the basis of their separation in ITD-F0 space. Source segregation is performed within individual frequency channels without recourse to across-channel estimates of F0 or ITD that are commonly used in auditory scene analysis approaches. The system is evaluated on spatialised speech signals using energy-based metrics and automatic speech recognition.

A novel extension to recurrent timing neural networks (RTNNs) is proposed which allows such networks to exploit a joint interaural time difference-fundamental frequency (ITD-F0) auditory cue as opposed to F0 only This extension involves coupling a second layer of coincidence detectors to a two-dimensional RTNN. The coincidence detectors are tuned to particular ITDs and each feeds excitation to a column in the RTNN. Thus, one axis of the RTNN represents FO and the other ITD. The resulting behaviour allows sources to be segregated on the basis of their separation in ITD-F0 space. Furthermore, all grouping and segregation activity proceeds within individual frequency channels without recourse to across channel estimates of FO or ITD that are commonly used in auditory scene analysis approaches. The system has been evaluated using a source separation task operating on spatialised speech signals.

A model of auditory scene analysis is proposed, which incorporates an attentional mechanism and is implemented using a network of neural oscillators. The core of the model is a two-layer neural oscillator network which performs stream segregation and selection on the basis of oscillatory correlation. A stream is represented by a sychronised oscillator population, whereas different streams are represented by desynchronised oscillator poplations. The output of the model is an 'attentional stream, describing which parts of the auditory scene are in the attentional foregrouns. The model simulates a number of perceptual phenomena including two tone streaming and the capture of a tone from a harmonic complex.

Structured recursive hierarchical models such as context-free grammars have applications in many areas and the attractions of the LR parsing strategy are such that generalisations which enable this strategy to be employed in new areas should be warmly welcomed by many researchers. An area of particular interest to us is the recognition of continuous speech and it was with this application in mind that the probabilistic LR parser was developed. However, there are likely to be other applications as well, perhaps in handwriting and optical character recognition and in certain compilers.

Participants in a teleconference often multitask during meetings, e.g., they work on a text‐based “foreground” task whilst listening in the 'background' for a topic of interest to appear. Audio material should therefore be presented in a manner that has the smallest possible impact on the foreground task without affecting topic detection. Here, we ask whether spatialised audio presentation of a meeting is less disruptive than the single‐channel mixture of talkers that is normally used in teleconference audio. Head‐related impulse responses are used to synthesise a stereo signal in which each meeting participant is placed at a spatially distinct location. A number of talker location configurations are used, and we examine how these impact upon a text‐based foreground task: finding all letter “e” occurrences in a block of text as quickly as possible. We also examine the effect of listening task (e.g., “listen for keyword x” versus “listen for keyword x spoken by talker on left”) and record listener preferences for audio presentation style. Our results suggest that single‐channel and spatialised audio are equally disruptive when listeners are unaware of the audio presentation style. We also report studies in which presentation type and target direction/gender are cued.

This paper examines the use of binaural cues for estimating the location of individual sources in multi‐source acoustic mixtures. In most environments, location cues such as interaural time difference (ITD) and interaural intensity difference (IID) are rendered unreliable by noise due to competing sources and reverberation. We propose a method that examines spectro‐temporal regions where such effects are minimised. Source location is estimated by combining two processing stages. First, following [Christensen et al, Interspeech (2007)], as pitch cues are generally less affected by noise, a multi‐pitch estimation and tracking algorithm is used to identify local spectro‐temporal 'fragments' in which the SNR is high. Second, the confidence of ITD and IID estimates arising from each time‐frequency 'pixel' is estimated based on interaural coherence [Faller and Merimaa, J. Acoust. Soc. Am. 116, 3075‐‐3089 (2004)] and reverberation estimation [Heckmann et al, Int. Conf. Int. Robots and Systems (2006)]. A location estimate is then constructed by integrating suitably weighted cues from each pixel within the fragment. Experiments are carried out on a large corpus of multi‐speaker data, mixed from binaural recordings in a real, reverberant environment. The fragment based processing is shown to provide significant improvements when compared to competitive baseline approaches.

A series of polyols was prepared from epoxidized tallow, by reaction with trimethylolpropane in refluxing toluene, sequentially under basic and acidic catalysis. In preliminary experiments, under catalysis by sodium methoxide alone, the trimethylolpropane reacted rapidly with glyceride linkages and very slowly with oxirane groups. Under catalysis by p-toluenesulfonic acid alone, oxirane was rapidly consumed. Polyols were prepared by the following sequences: (A) reaction under acidic followed by basic catalysis; (B) reaction under basic followed by acidic catalysis; (C) reaction under basic catalysis followed by further treatment with HBr gas to introduce fire retardance; (D) treatment of whole tallow first with trimethylolpropane under basic conditions and secondly with bromine; (E) reaction of epoxidized tallow with diethanolamine under basic catalysis; and (F) treatment of epoxidized tallow first with trimethylolpropane under acidic conditions and then with diethanolamine under basic catalysis. The polyols described were adjusted to equivalent weights of 100 and 120 with added triisopropanolamine and treated with a polymeric isocyanate to give rigid foams. Densities ranged from 1.5–1.8 lb/ft3. Open cell content, for foams made at the equivalent wt of 100, ranged from 14–21%; at the equivalent wt of 120, from 17–27%. Compressive strengths ranged from 14–23 psi, being lower than those of the best previous epoxidized tallow-trimethylolpropane products.

The viscosities obtained for the copolymer blends of the previous paper were correlated with several relations derived to describe more fundamental behavior of polymer–diluent mixtures at both infinite dilution and finite concentrations. Only the most efficient blends showed any appreciable expansion of hydrodynamic volume as temperature increased from 25° to 98.9°C. However, in spite of restricted coil expansion, all of the copolymers were effective viscosity index improvers. The mechanism of viscosity index improvement in multigrade oils was shown to be largely regulated by the translational friction generated by the polymer coils. This greatly increased the apparent negative entropy change of the blends; the enthalpy change characteristic of the base oil was retained. Efficiency resulted from coil contraction at low temperatures, but enthalpy decrease below that of the base oil was small. In contrast, viscosity index improvement using higher molecular weight solvents was accompanied by large enthalpy increases. Thus, undesirably high viscosities resulted at low temperatures. The structure of these blends was uncomplicated by polymer chain entanglements; unit values of the Fox-Flory exponent were obtained for the relation between viscosity and weight-average carbon backbone length. The lack of evidence for coil compression in the thermodynamically miscible blends above a critical reduced concentration was anomalous. Intermingling of side chains and their interaction may have overcome normal excluded volume effects.

Polyols of higher hydroxyl content than previously obtained from tallow were prepared for use in urethane foams. Epoxidized tallow was caused to react with trimethylolpropane with catalysis by p-toluenesulfonic acid (2%). Reaction at 120 C in toluene gave best results. Alcoholysis occurred both at oxirane and at glyceride linkages, the latter reaction conferring hydroxyl functionality even on nonepoxidized glyceride units. Hydroxyl content of polyol products increased with the functional ratio of the reaction mixture, that is, the molar ratio of OH available from trimethylolpropane to oxirane plus ester from tallow. To provide fire retardant polyols, epoxidized tallow was caused to react with trimethylolpropane and gaseous HBr, best at 80 C in benzene. Examined by thin layer chromatography, the polyols showed polarities in the range of mono-and diglycerides.

Several nitrile rubber elastomers were polyblended, across the composition range, with selected polymeric compositions containing vinyl chloride. The compositions incorporated were (a) bulk poly(vinyl chloride) (PVC); (b) copolymers of vinyl stearate and vinyl chloride containing, respectively, 0.21, 0.36, and 0.47 weight fraction of the vinyl ester; and (c) mixtures containing the same weight fractions of di-2-ethylhexyl phthalate (DOP) with PVC. Mechanical, viscoelastic, optical, and volatility properties were studied on all blends in this first paper. To accurately compare the mechanical properties of polyblends of different systems, a criterion of mechanical equivalence was taken as the observance of similar stresses at break for compositions selected to have identical 100% moduli. Optimum mechanical equivalence, therefore, occurred at the largest ratios of 100% modulus to break stress for all systems compared. Optimum mechanical property equivalence was observed for NBR blends with PVC and for similar blends of both internally and externally plasticized systems containing 0.21 weight fraction of plasticizer. However, considerably more nitrile rubber was needed for PVC blends to acquire the properties of the plasticized systems. Mechanical equivalence was observed, but was not optimum for systems having more plasticizer because tensile strengths were lower. Polyblending with NBR improved the toughness and low-temperature properties of starting vinyl stearate copolymers. Improved toughness was indicated by the expansion of areas under stress–strain curves. Refractive index matching appeared to explain the transparency of the best films and their relative freedom from haze. On heating at 85°C, poly(vinyl chloride) and the copolymer polyblends suffered no volatility loss. Volatility of DOP from the blends was 1.5 times greater than for PVC–DOP mixtures. Because modulus–temperature curves and mechanical Tg values of the filler component shifted with composition, the mechanical behavior of these blends was in harmony with an accepted standard of interdomain compatibility.

Isochronal viscoelastic parameters were obtained for the polyblends of nitrile rubbers with internally and externally plasticized poly(vinyl chloride) (PVC) whose mechanical properties were studied in the previous paper. Thus, the room-temperature mechanical properties of the previous paper were extended to included a wide temperature range in this work. Phase immiscibility, indicated by the observance of two glass transition temperatures, using differential scanning calorimetry, was observed for most of the polyblends. In contrast, blend compatibility was indicated by mechanical measurements, because the inflection temperatures of the isochronal curves (Ti) shifted with blend composition. It was concluded that mechanical spectroscopy-monitored volume elements large enough to include contributions to viscoelastic response from both phases; this caused the curves to shift with composition. On the other hand, the much shorter-range segmental responses characteristic of Tg produced transitions at the discrete temperature intervals representative of each phase. Using a relation between torsional stiffness at room temperature and tensile strength, failure strengths with respect to temperature were estimated and compared at varied free-volume increments (T − Tg) up to 50°C. Approximate equivalence was found by this procedure for fillers of bulk PVC and those containing 21 wt-% of both internal and external plasticizer, in analogy with findings for mechanical property optimization of the previous paper. Low-temperature properties and viscoelastic response of the polyblends containing vinyl stearate copolymers were greatly improved over their neat state. In addition, data from isochronal temperature–composition diagrams suggested viscoelastic equivalence, but greater ease of processability for the blends containing vinyl ester, compared to the others.

Compositionally and structurally varied copolymers all containing n-octadecyl acrylate were prepared and evaluated as viscosity index improvers in a common base oil under conditions of low shear. Systems evaluated over a range of copolymer and blend composition were: copolymers of n-octadecyl acrylate with, respectively, methyl methacrylate, 2-ethylhexyl acrylate, and n-dodecyl acrylate; and homopolymers of poly(n-octadecyl acrylate), prepared with a wide range of molecular weights. Properties were compared with those of blends of commercial methacrylate copolymers (acryloids) which had been freed of their entraining liquid. Mixtures of base oil with copolymers of n-octadecyl acrylate and methyl methacrylate, compared at fixed SAE viscosities, were the most efficient of all blends studied. They had the smallest rate of change of viscosity with temperature (as measured by their ASTM slopes), particularly in the composition region of incipient polymer precipitation at room temperature. Efficiency of certain of these composition was somewhat greater than that of the acryloids. A parameter that related concentration and weight-average molecular weight was used to correlate all of the data for ASTM slope and viscosity. Empirical relations developed by using this parameter enabled rheological data to be estimated that agree within 6% of experimental values for the case of thermodynamically good base oil solvents. These data demonstrated the relatively small contributions of copolymer structure to viscosity index improvement.

‘Postmodernisation’ is introduced as a unifying concept for the set of processes which characterise the development of the space economy in the 1980s. The concept consists in effects which include: an increase in the unevenness of developmental potential between ‘inner’ and ‘outer’ British regions, growing polarisation in income and unemployment indices over space, a shift towards economies of scope by producers, a growing dynamism in localities with large service-class components displaying a privatistic consumption culture, and a growth of casualised and informal labour-market opportunities at the expense of ‘lifetime’ employment. This contrasts with a set of processes characteristic of what may be termed the ‘modernisation’ period circa 1945–1975 in which there was a relatively even spread of developmental opportunities across regional space, there was income and employment convergence, production pursued volume markets and economies of scale, collective consumption provision was socially predominant and employment was relatively secure. It is suggested that this change is consistent with but by no means fully explained by the recent monetarist shakeout of the British economy.

A laboratory survey of the properties of a series of ethenoxylated fatty acids and alcohols containing about 10, 15, 20, 30, and 40 ethenoxy groups per molecule has brought together information on solubility, cloud point, surface and interfacial tension, detergency, and wetting, foaming and emulsifying properties.

Dichlorocarbene was generated in the presence of lard, olive, safflower, tung and menhaden oil. When solutions of fats or oils in ethyl trichloroacetate were mixed with sodium methoxide inn-heptane at 2C, unsaturated components were transformed in high conversion to dichlorocyclopropane derivatives; fats were converted to methyl-and-ethyl esters (90%) or appeared as glycerides (10%). The proportion of dichlorocyclopropane rings was the same in the glycerides as in the ester products. The reactivity of safflower oil required metered addition of reactants at 25–55C. Properties were measured on dichlorocyclo-propanoid fatty esters freed from glycerides but containing saturated esters. Chlorine content ranged from 12–33%. Compatibility with silicone oils was substantially improved. Viscosities and densities increased with chlorine content. Viscosity indices were 135,150,49,67 and 79 for products from lard, olive, safflower, tung and menhaden oil. Dichlorocarbene could be generated without alcoholysis of glycerides by decomposition of sodium trichloroacetate. This gave dichlorocyclopropanes from safflower oil unsaturates in 50% conversion, but failed with lard. Analyses were performed by TLC, argentation and GLC.

Apparent transfer constants have been determined for styrene, methyl methacrylate vinyl acetate, and diethyl maleate polymerized in N-allylstearamide at 90°C. Regression coefficients for transfer were: methyl methacrylate, 0.301 × 10−3; styrene, with no added initiator, 0.582 × 10−3; styrene, initiated with benzoyl peroxide, 0.830 × 10−3; vinyl acetate, 62.01 × 10−3; and diethyl maleate, 2.24 × 10−3. Rates of polymerization were retarded for both styrene and methyl methacrylate. Vinyl monomer and comonomer disappearance followed an increasing exponential dependence on both initiator and monomer concentration. Although degradative chain transfer probably caused most of the retardation, the cross-termination effect was not eliminated as a contribution factor. Rates for the vinyl acetate copolymerization were somewhat retarded, even though initiator consumption was large because of induced decomposition. The kinetic and transfer data indicated that the reactive monomers added radicals readily, but that rates were lowered by degradative chain transfer. Growing chains were terminated at only moderate rates of transfer. Unreactive monomers added radicals less easily, producing reactive radicals, which transferred rapidly, so that molecular weights were lowered precipitously. Although induced initiator decomposition occurred, rates were still retarded by degradative chain transfer. A simple empirical relation was found between the reciprocal number-average degree of polymerization, 1/Xn1 and the mole fraction of allylic comonomer entering the copolymer F2, which permitted estimation of the molecular weight of copolymers of vinyl monomers with allylic comonomers. This equation should be applicable when monomer transfer constants for each homopolymer are known and when osmometric molecular weights of one or two copolymers of low allylic content have been determined.

When either pure N-allylstearamide or mixed allylamides, made by the aminolysis of hydrogenated tallow, were heated at 90C for 3 hr with benzoyl peroxide, the reaction products were medium-hard, high-melting (ca. 70–80C) waxes of light color suitable for use in polish applications. Hardness increased with increase in benzoyl peroxide, reaching an optimum for 3 to 8 g of peroxide per 100 g amide. Qualitative floor-wear tests on films obtained from paste and emulsion compositions showed the allylamide waxes to be inferior to carnauba and a Fisher-Tropsch wax, but superior to several other synthetic waxes including polyethylene. No special property advantage was found using pure allylsteara-mide. Resistance to oxidation at 90C was good and the waxes emulsified readily. In the reaction of allylstearamide with benzoyl peroxide, polymer formation depends strongly on catalyst concentration (d M/dP=2, compared to 14–50 for allyl esters) and some products of substitution and induced decomposition are formed. Wax properties were related to polyallylstearamide content.

Kinetics of the aminolysis of hydrogenated tallow by allylamine in methanol solution under sodium methoxide catalysis was studied at several temperatures (60 to 90C) and catalyst concentrations. Under the experimental conditions the triglycerides were rapidly converted to the mixed methyl esters, which slowly reacted with the amine to produce the mixed amides. At constant catalyst concentration, disappearance of triglyceride was found to be first order in triglyceride and in amine. Because rate was found to be directly proportional to catalyst concentration, the experimental over-all rate was −d[Triglyceride]/dt=k3[Triglyceride] [Amine] [RO−], and k3 was 2.022 kg2 mole−2 hr−1. A mechanism proposed by Bunnett and Davis for ester aminolysis involving an ester-amine complex formed in a rapid pre-transition-state equilibrium is consistent with thermodynamic terms which reconcile a large negative entropy of activation (−44.17 cal deg−1 equivalent−1) and relatively small energy of activation (11.60 kcal equivalent−1). Relative rate constants at 70C under sodium-methoxide catalysis for the aminolysis of hydrogenated tallow by a variety of structurally different primary amines agreed, in general, with those found by others for the ethylene glycol-catalyzed reaction of methyl acetate with the same amines at 25C. However, monoethanolamine reacted nineteen times faster than predicted, which suggested a mechanism involving initial attack by the alkoxy anion of the ethanolamine in the rate detering step, followed by rapid, base-catalyzed, acyl acyl oxygen-to-nitrogen (O→N) migration. The velocity constants and thermodynamic constants reported enable prediction of the time required for specific yields under a variety of experimental conditions.

The monomer reactivity ratios and the corresponding copolymerization parameters for the copolymerization of N-octadecylacrylamide (M1) and several monomers in tert-butyl alcohol at 60 ± 0.1°C. were determined and were: with acrylonitrile, r1 = 1.44 ± 0.019, r2 = 1.10 ± 0.035; Q1 = 0.60, e1 = 1.20; with vinylidene chloride, r1 = 1.37 ± 0.008, r2 = 0.438 ± 0.008; Q1 = 0.65, e1 = 1.08; with vinyl acetate, r1 = 6.11 ± 0.045, r2 = 0.027 ± 0.009; Q1 = 0.72, e1 = 1.12. The mean copolymerization parameters, therefore, were Q1 = 0.66, e1 = 1.13. The reactivity ratios and the corresponding copolymerization parameters for the copolymerization of N-ally lstearamide (M1) and several monomers, polymerized in tert-butyl alcohol at 80 ± 0.1°C. (except for vinyl acetate, polymerized in bulk at 70 ± 0.1°C.) were determined and were: with acrylonitrile, r1 = 0.118 ± 0.084, r2 = 3.61 ± 0.087; Q1 = 0.058; e1 = 0.21; with vinylidene chloride, r1 = 0 ± 0.136, r2 = 5.23 ± 0.067; Q1 = 0.028, e1 = −0.80; with vinyl acetate, r1 = 0.0532 ± 0.012, r2 = 0.740 ± 0.087; Q1 = 0.043, e1 = −1.18. The mean copolymerization parameters for N-allylstearamide were, therefore, Q1 = 0.043, e1 = −0.59.