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A comparative study is made between three methods for balancing single-model assembly lines. These include: 10-SP, which selects the best of ten single-pass solutions; ARCUS—a random multi-pass method, and MALB, an iterative backtracking method. The assembly tasks contain up to 140 work elements with widely differing precedence structures. Measurements of the Balance Delay are used for comparing the solution efficiencies and computation times are also compared. The experiments show significant differences between the three line balancing methods and that these differences are accentuated for certain conditions of task size, precedence structure and the imposed balancing requirements. It is shown that 10-SP is yet another simple but effective technique for balancing single-model assembly lines.

The interaction of the social and medical sciences lacks an adequate integrative model for facilitating inter-disciplinary research. An attempt is made to synthesize findings in the area of hypertension from the disciplines of sociology and psychology toward formulating a single model for guiding future research. The intervening role of perception for studying social and psychological factors in hypertension is explored. Using the proposed model for subsequent research in diseases with social factors implicated as etiological, may be a step toward furthering understanding of these disease processes.

The purpose of the present investigation was (a) to examine the effect of two variables in developing assertive behavior using covert modeling and (b) to develop a technique to assess ongoing imagery during treatment. In a 2 × 2 design, the number of models imagined (imagining several models versus imagining a single model perform assertively) and model reinforcement (imagining favorable consequences following model behavior versus imagining no consequences) were combined. A nonassertive-model control group that imagined assertion-relevant scenes was included in the design. The results indicated that imagining multiple models or model reinforcement enhanced behavior change across self-report inventories and a behavioral role-playing test. Treatment effects transferred to novel role-playing situations and were maintained at a 4-month follow-up assessment. Assessment of imagery during the session corroborated the adherence of subjects to the imagery conditions to which they were assigned. However, subjects systematically introduced elaborations into the scenes. The data suggest the importance of assessing imagery in covert conditioning therapy studies.

This paper presents the results of simulating two-locus systems with Batesian mimicry, with special reference to the evolution of dominance. Systems with a single model, and with two species of models, and their mimics are considered. With one species of model, it is shown that either dominance or recessivity of an original mimicry gene may evolve, depending on the equilibrium state that is reached before the modifier mutation occurs. Using this system, we offer a possible explanation for the recessiveness of the mimicry gene in the Abyssinian population of Papilio dardanus. With two species of model, the system becomes too complex to draw more than partial conclusions, and it seems unlikely that considerations of dominance modifiers alone are a sufficiently informative basis for firm prediction.

We present a single model of the fields in a spiral resonator and compare the predicted properties with those from experiment. The model gives a very good representation of the resonant frequency of the cylindrical resonator and of the fields in all regions away from the immediate neighborhood of the midplane spiral. Shunt impedances cannot be accurately predicted because the model simplifies the form of the spiral, which affects the electrical field along the cavity axis.

j ABORATORY tests were con-1^ ducted with a single model track operating straight line at low speed in level test beds of air-dry sand and of near-saturated clay. Dimensionless terms composed of independent (con-trolled) track and soil variables were developed to predict track perform-ance in the two soil types. Four performance levels (the towed, self-propelled, 20 percent slip, and maximum tractive efficiency condi-tions) and five performance variables (pull, towed force, torque, sinkage, and trim angle) are considered. Validation tests indicate that both the sand and the (preliminary) clay prediction terms can be used to describe prototype vehicle perform-ance

In covert modeling, subjects imagine a model rather than observe a live or film model. In a 2 × 2 design, multiplicity of models (imagining one vs three different models) and variation of fear stimuli (imagining the model perform with one vs two different snakes) were combined. A no-model control group was included in the design to control for fear-related imagery in the absence of a model. Subjects who imagined multiple models, as opposed to a single model, showed greater avoidance reduction on behavioral and self-report measures at posttreatment and at a 3-week follow-up assessment. Subjects who imagined a single snake and those who imagined different snakes were not different in avoidance. In general, the results supported the efficacy of covert modeling over no-model controls.

The term vernacular architecture is being increasingly applied to the buildings used by ordinary people, especially in pre-industrial societies.1 Vernacular architecture characteristically exhibits consid erable regional variety of style. Within regions there is marked and voluntary adherence by the majority of society to a single model or ideal pattern of house form. Even though professional builders may be operating, the basic model is not seriously questioned by builder or peasant. The model has no designer but is part of the anonymous folk tradition and tends to be persistent in time. Conformity, anonym ity, and continuity may be seen as the hallmarks of regional vernacu lar architecture, reflecting the cultural coherence, simplicity, and con servatism of peasant communities and the deep rooted traditions within the building crafts. With the growth of commercial agriculture and industrialization in particular, rural society becomes more strati fied and diverse. Building activities respond. There is more variety in house design and departure from traditional models. Regional differ ences are also blurred or eradicated. But the decay of the vernacular tradition in domestic building is difficult to date precisely because it is a protracted process and proceeds at a different pace from region to region. Even with the advent of machinery and the mass production

In three experiments pairs of Ss (sixth, seventh, and eighth graders in Exps. I and II; third and fourth graders in Exp. III) learned four consecutive sets of one of three PA transfer paradigms (A-B′, C-D, A-D), yoked observers alternately listening to the List-1 performances of models and learning the transfer lists directly. On Set 4, Ss either continued learning on the same paradigm or were switched to a different paradigm. Results for model Ss closely replicated earlier findings with adults, overall performance on List 1 increasing over sets and transfer on A-B′ showing marked increments from Set 1 to Set 2. Observers showed poorer transfer than models across paradigms, although the data suggest the presence of a complex Paradigm × Conditions of Learning × Age interaction. For both models and observers there was no Training Paradigm × 4th-Set Test Paradigm interaction, performance on Set 4 being dependent solely on the nature of the test paradigm. In Exp. III, exposure to different models over successive sets yielded consonant results with single model exposure.

A simple holographic recording of a photo-elastic object under stress allows the isochromatics to be observed. The isopachics are obtained by double-exposure interferometry: a second traverse of the wavefront through the object after a 90° rotation of its polarization by a Faraday cell eliminates the unwanted isochromatics.

Various theories of fibre structure are briefly reviewed, and it is shown that the original ‘fringed-micelles’ theory is no longer considered valid. The influence of the genesis of fibres on their structure is demonstrated, and it is shown that, because of this difference in fibre formation, it is difficult to fit a single model to all fibres. The architectural models proposed for various fibres are discussed, and it is pointed out that the validity of these models can be tested by reference to the fibre properties. It is emphasized that there is still insufficient knowledge of the behaviour of fibres subjected to transverse stresses, and it is shown that some of the phenomena that occur under the action of such stresses can be explained by the comparatively recent ‘fringed-fibrils’ theory of fibre structure. Finally, attention is drawn to some aspects of the structure and behaviour of fibres that are still unexplained, and towards which it is proposed that further research should be directed.

Leads were used to determine the activity of the optical radiation fibers, studying the responses of the cat's CGL receptive fields to changes in the surface size and illumination of a testing light spot and the illumination of the background. Three types of receptive fields were found. The receptive fields type I are characterized by a reduction in the zone of central summation as illumination of the spot increases. For fields of types II and III this zone remains unchanged when the illumination changes; however in fields of type II the response increases with an increase in lighting while in the type III fields the response does not depend on illuminance of the spot. There also exist differences in responses of the various fields to changes in the background. All the receptive fields can be described by a single model. Changes in individual parameters of the model permit transition from one field type to the other.

Publisher Summary This chapter describes sensitivity dipole and the sensitivity points method. In addition to the general methods of computing sensitivity functions, several special methods have been developed for certain classes of systems. Among these, the method of sensitivity points is particularly useful for linear systems, offering two important advantages. All sensitivity functions can be obtained simultaneously from a single model that is identical to the model of the basic system. To obtain sensitivity function, it is sufficient to apply at the input of the sensitivity model the output of the signal of the basic system or its model. The method of sensitivity points is based on a structural interpretation of logarithmic sensitivity function. The sensitivity points are defined as those points in the system up to which, starting from the input of the system, the transmittance is equal to the logarithmic sensitivity function.

Recent developements in analytical photogrammetry seem to be remarkable, especially with the expansion in the ield o its application, and also the demand or higheraccuracies in photogrammetric surveying is growing day by day, throwing beore us many interesting problems.Due to the recent developments in analytical photogrammetry, we have become convinced that these problems can be solved. Having been engaged in analytical photogrammetry during the past six years, we recently examined the inluence of the lens distortion on accuracies, and we ound that it was unexpectedly large. In this paper, we will discuss the problems which we had to deal with and the particular applications o the results.First o all, the method o analysis and the corrections or symmetric and asymmetric radial lens distortions will be shown and secondly we will make observations rom various standpoints on the phenomena which appeared in the actual examples when applied the lens distortion correction i. e. the inluence on a single model, on a strip and on the relation between the bending coeicient o a strip and the variations o orientation elements caused by the lens distortions.

Frequently, one reads in the literature about “the” emergency room, as if all emergency rooms were similar and a single model would suffice to describe them all. In this interview-survey of 1,113 patients attending the emergency rooms of four hospitals in New York City, however, it was found that each emergency room served very different populations and played very different roles in the medical-care patterns of those patients. As a result of this study and of a review of the previous literature, the authors suggest that there are three major roles for emergency rooms: 1. trauma treatment centers; 2. physician-substitutes when a private practitioner or out-patient clinic are not available; and 3. “family physician” to the urban poor. These roles are not mutually exclusive and all can be present to some degree in any one emergency room.

Recent impasses reached by nuclear theory, a recurrent desire to interpret quantum phenomena in mechanistic terms and a certain loss of glory suffered by the general theory of relativity make it appear timely, perhaps, to review discarded attempts at common-sense explanations of atomic and relativistic physics, making sure that they have not been too hastily rejected. Mr. Hartley has been a persistent and circumspect advocate of a mechanical view which, even if it cannot claim to solve all problems in the universal flash of brilliance for which physicists and philosophers have waited in vain for decades, raises worthwhile points for consideration. The nature of this task and the preoccupation of technical journals with imminent matters singles out our journal as the proper carrier for Mr. Hartley's thoughts. They are here presented without mathematical detail but in a manner suggestive of the unity of his treatment. Technical details are discussed in some of the items of the bibliography.

Results of a two-dimensional photoelastic study of turbine-shell flanges are reported. Equations of transition from model to prototype are given. A special loading jig for applying a uniform pressure to the boundary of a plane model is described. Pertinent aspects of the experimental technique are summarized.

In this article an extension of the learning curve concept is introduced by considering the rate of reduction in direct labor assembly time for mixed model assembly situations. Here, more than one model is assembled on the same assembly line; hence, the repetitions of the assembly work are not always the same. Following a short description of the mathematical formulation of the learning curve (for convenience called the single model learning curve), a development of a mixed model learning curve is presented. An example is given to demonstrate the application of mixed model learning.

Measurements have been made of the sorption of O 2 , Ar, CH 4 , C 2 H 6 , C 3 H 8 , n -C 4 H 10 , iso-C 4 H 10 , n -C 5 H 12 , neo-C 5 H 12 , n -C 6 H 14 , C 6 H 6 and cyclo-hexane in a sodium-potassium form of zeolite L. In some cases heats of inclusion have been evaluated as functions of amounts sorbed. For the n -paraffins C 1 to C 4 the initial isosteric heat q st obeyed the equation q st = 4.8 + 2.2( n − 1) kcal per mole where n denotes the number of carbon atoms. This additive property of q st indicates that it is dominated by dispersion and repulsion energy contributions. As the amount of included hydrocarbon increases, sorbate-lattice interaction is augmented by sorbate-sorbate interaction, leading to maxima in the heat curves near saturation. Saturation values appear to decrease rather rapidly with increasing temperature.

The E- and F1-layer data obtained at pairs of stations during the eclipses of 1952 and 1954 were consistent on each occasion with a single model for the distribution of sources of ionizing radiation on the sun. The results obtained at Singapore in December 1955 can not be explained in terms of any likely distribution. It seems possible that vertical movements, and the consequent invalidity of the Chapman theory, may have been responsible for this discrepancy. No significant change occurred in the critical frequency of the F2-layer but there is evidence of a complex redistribution of ionization in the lower part of the F-layer.

This paper deals with the development of a new model for a class of microwave filters. With this model one can reproduce and systematize from a general viewpoint results now in the literature. Its most prominent feature, however, is that the use of the model permits the development of a synthesis procedure for the wide-band filter. From this single model a wide variety of structural realizations are readily obtained. Designs employing this model, and the appropriate synthesis, show significant improvement of desired characteristics over conventional designs. The general multiple quarter wave matching transformer problem is also discussed.

Two-dimensional photoelasticity is used for minimising stress concentration associated with a fillet present at the end of a solid propellant rocket grain subjected to restrained shrinkage. For this purpose, successive holes were added along the bonded interface of case and propellant, but no decrease was obtained. The photoelastic method used illustrates two uncommon techniques of interest to experimental stress analysts: (1) restrained shrinkage loading and (2) a parametric stress-analysis solution obtained with a single model.

Glasses in the systems As2S3As2Se3 and As2Se3As2Te3 have been studied. Optical absorption at room temperature and electrical conductivity at temperatures between 30°C and 150°C have been measured. It is concluded that no single model of conductivity is applicable to all materials. The results are consistent with the suggestion that the conductivity may be controlled by potential barriers arising from structural and compositional fluctuations.

THIS PAPER REPORTS the preliminary results of a project aimed at developing an empirical model explaining capital flows among the major OECD countries. The work is based on the portfolio-equilibrium, stock-adjustment view of capital flows.' Here we discuss the estimation of equations explaining the net capital flows-the capital account balancefor six countries: the U.K., Canada, Japan, France, Western Germany, and Italy. Even with these highly aggregated and imperfect data, stable relationships between net flows and various interest rates can be estimated. In section II we briefly discuss the stock-adjustment view and its implications for specification of capital flow equations. We then develop a specific estimating equation for the OECD net flow data at our disposal. Next, in section III, we report the estimated equations for total net flows of private capital into the six countries. In this preliminary study no attention is paid to problems of simultaneity or to questions of adding-up consistency across the equations. Nevertheless, we find that many short-term and long-term interest rates, income velocities of money (v = GNP/M1), and trade flows are significant in explaining the six capital flow series. Satisfactory equations are estimated for the U.K., Canada, Japan, and Germany; those for France and Italy, while statistically significant, are less satisfactory. A separate, six-equation model of the U.S. capital account is added in section IV. This model is reported fully in Branson and Hill (1970), and is only summarized here. The equations were estimated on data consistent with the six country equations, so the complete set of equations can be viewed as a single model. In section V we present and discuss a multiplier table that summarizes the equations estimated in sections III and IV. The table can, in principle, be used to study the effects of monetary policy changes in one country on the flows into each of the seven countries. Of course, since the section III equations are highly preliminary estimates, so are the section V multipliers. Finally, we conclude with some comments of caution, and a suggestion that further work begin with disaggregation of the net flow data into net changes in assets and liabilities by country.

Some mechanisms related to the excitation of atoms passing through foils are discussed. Simple models simulating these mechanisms are constructed and calculations performed in an attempt to gain qualitative understanding of the excitation process. Though no single model has been found to provide a reasonable guide to this complex problem, some qualitative relationships not in disagreement with experiment emerge. The energy dependence of electron capture by protons in a foil follows a E p −3 law at higher energies, consistent with recombbination in streaming plasmas. The role of inner-shell processes is also discussed.

Experimental data from several different climatic regions were used to develop a statistical model for actual water loss rates from land surfaces. The actual evapotranspiration rate was considered to be influenced by the amount of available water in the soil and by meteorological and plant conditions which determine the potential evapotranspiration rate. Experimental measurements of these three variables from various environmental conditions were combined into a single model expressing the composite relationship. Actual evapotranspiration rates were calculated from this relationship using the variables soil moisture and potential evapotranspiration. Initial testing showed that the model gave satisfactory results when used for estimating moisture changes in the soil.

The stereochemical course of the reaction between organo-metals and β-asymmetric amino-ketones has been investigated by varying the nature of the reagent and the substituents in the substrate, as well as the distance of the amino-group from the reaction center. The relative configurations of the diastereomeric amino-alcohols obtained were assigned, thus determining the direction of the predominant attack by the nucleophile. The stereoselectivity was found to be strongly dependent on the factors investigated, particularly on the nature of the amino-group and of the reagent. No single model of asymmetric induction proved to be suitable for the prediction of the stereochemical results in the above reactions.

Sltmn2ary.-This paper cities several areas which have received little attention in the literature on behavior therapy. It is suggested that these areas are important from the standpoint of practicing and evaluating a behavior rherapeutic approach to maladaptive behavior. The issues include diagnosing, dealing with more realistic response classes, getting objective measures of additiona1 relevant variables, selecting appropriate behavioral modification techniques for rhe particular case, exploring stimulus conditions leading to the maladaptive behavior, and reporting the carry-over of behavioral changes produced in the experimental environment to the natural environment. In spite of the growing literature on methods and applications of behavior therapy, few papers evaluate this work in light of actual therapeutic demands. Despite the many studies demonstrating the utility of the approach and its potential benefit, there are a number of important issues that have as yet received too little discussion in the literature. These iss~les are discussed in this paper. Although many well-traincd therapists are aware of these issues and each point has received some mention in the literature, in general they have been neglected. Further, while chis paper is written in the context of behavior therapy, it is believed that each point has bearing on other therapies as well. A variety of behavior modification techniques derived from the operant and classical conditioning literature have been described (Bachrach, 1962; Eysenck, 1964; Grossberg, 1964; Kalish, 1966; Rachman, 1963; Truax, 1966; U11man & Krasner, 1965; Wolpe, 1958; Wolpe & Lazarus, 1966). If behavioral change is the goal of therapy, these procedures are important. Techniques include shaping, reinforcing. extinction, desensitization, negative practice, escape and avoidance training, stimulus control, role-taking, and others. Their advantage lies in their being based on principles supported by considerable evidence from st~tdy of both animals and humans. This past research and specific techniques give the behavior therapist a valuable framework and practical armamentarium for approaching a situation in which his aim is to alter behavior (Bandura, 1961). An advantage of this work is that it is relatively precise and objective. Its operational natiue permits the reader to know precisely what behavior is under smdy and what the therapist does in his efforts to modify the behavior. While having a framework of functioning is desirable, this frame of reference should not be too limiting. Rather than viewing therapy as plugging maladaptive behavior into a single model, the therapist should be attuned, as the ex

This paper is concerned with the development of a heuristic algorithm (MALB) for the general solution of large single-model assembly line balancing problems. It is based on the optimum-seeking backtracking method proposed by Mansoor (1964). Excellent results were obtained from tests taken over a wide range of large ALB problems. Over a third of the tests yielded a 100% line efficiency and the overall computation time was 22 sec on an IBM 7040/7044.

The paper by Heady and Hall may be divided into three parts: 25 percent of the space is devoted to an introduction and brief enumeration of past spatial studies; 70 percent is allotted to a brief synopsis of two previous studies which Heady has co-authored; and 5 percent (the last three paragraphs) is devoted to a comparison of various types of models. Let me limit my comments to this last 5 percent. They indicate that the usual representative-farm programming models can more accurately reflect short-run resource immobilities than can regional spatial models because the latter assume complete resource mobility among farms in a given region. They suggest that the prospect of combining in a single model the essential characteristics of both regional and typical-farm models "is almost upon us" but leave us in suspense regarding how this might be done. Fortunately, we are not left in suspense very long because Sharples and Schaller claim that they have provided a partial solution to the aggregation problem by using flexibility restraints. However, their concern is with aggregation at a different level: response of an entire region treated as one producing unit vs. individual farm response. So there are really four levels of aggregation involved-all farms in a region treated individually, several farms representative of many others not appearing in the model, one typical or average farm representing all farms in a region, and a region treated as one large farm. If the gap between individual-farm models and regional models can be partially bridged by the use of flexibility restraints, this same technique should be useful in bridging Heady and Hall's gap between representative-farm models and regional models. I will, therefore, confine the remainder of my remarks to the use of flexibility restraints in the Sharples-Schaller model. First, let me say that I am not a strong proponent of using linear programming for positive, short-run supply response predictions. The difference between what profit maximizers should do and what farmers actually do is fairly large, and to my knowledge there have been few successes in predicting short-run supply within a linear programming framework. However, I do see considerable promise in this area with the use of sophisticated flexibility restraints. Although Sharples and Schaller do use flexibility restraints, I would call theirs naive flexibility restraints.

This report develops a framework which structures the variety of modeling approaches that might be taken in quantifying visual target acquisition. Significant omissions in current modeling efforts are identified. Past modeling approaches are described, including those emphasizing cognitive and subjective approaches. It is concluded that mathematical modeling is so dependent upon (1) the objectives of the user, (2) the class of situation being modeled, and (3) the methodological orientation of the modeler, that a single model cannot meet all requirements. This report is particularly useful to those engaged in modeling who desire an overview of modeling techniques.

In this paper I would like to address several basically independent issues relating to the processes of natural language generation (NLG) and research on modeling these processes. In the subsection "Paradigms for Generation" I maintain that, viewed at a moderately abstract level, the vast majority of current research in this area falls into a single model and focuses on the "tail end" of the language generation process. The difference between individual models seems to be based on differing assumptions or convictions regarding the nature of "pre-generative" aspects of language use.

1. The names and functions of the main mesothoracic flight muscles in Lepidoptera are reviewed. 2. The wingbeat period in saturniid moths and monarch butterflies is long and variable. The three parameters, wingbeat period, burst length (number of times a motor unit is activated per wingstroke) and stroke amplitude are interdependent and positively correlated. 3. Partial amputation of the wings in saturniids decreases wingbeat period. Cutting the sensory nerves from the wings increases the period. These results indicate that the influence of wing movement on wingbeat period is mediated by receptors near the base of the wing. 4. The central nervous mechanisms which generate motor patterns during flight in Lepidoptera are discussed and compared with those in locusts. It is proposed that both mechanisms can be described by a single model, with minor differences in the mechanism of burst production.

Conflicting ideas regarding popcorn (burst) noise are compared. It is shown that it is premature to use a single model or claim for a unique representation and explanation.

THE actual configuration in space-time of micro pulsation activity has long been the subject of controversy, and no single model has been able to explain all the features of the different types of micropulsations. This communication concerns the method by which impulsive Pi2 (ref. 1) micropulsations spread over the Earth. Such micropulsations are recognized more easily on the night side of the Earth, although they can be detected on the daylight side also if not masked by other daylight micropulsations such as Pc3, Pc4 and Pc5 (ref. 1).

Electron microscope obesrvations of neutron-irradiated Cu and Au indicate two differences in the nature of the damage: the average spot diameter remains constant in Au but increases in Cu with increasing. exposure; and the spot density increases more rapidly with integrated neutron flux in Au than in Cu. Brinkman, et al., (J. Nucl. Mater., 4: incompatible with a single model of spot production. The author points out that the observations can be explained by defect migration and agglomeration, and that certain experimental facts are in accord with such a model. (W.D.M.)

The anchorage of career perspective is a mechanism common to both the unlimited and limited success orientations toward occupational mobility. The two models of motivation can be considered complementary; they refer to two outcomes of a more general model. The more general model requires that a career perspective be anchored to some reference point, which may be either the starting point of a career, or the level of maximum possible achievement. Level of occupational aspiration need not be treated as determined by separate mechanisms for each level, as current theory sugguest.'7 The more general and parsimonious conception, career anchorage, generates all levels of occupational aspiration from a single model.