bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Behavioralist Visits the Factory: Increasing Productivity Using Simple Framing Manipulations
Authors: Hossain Tanjim , List John A. 
Published: July 2012

Recent discoveries in behavioral economics have led to important new insights concerning what can happen in markets. Such gains in knowledge have come primarily via laboratory experiments—a missing piece of the puzzle in many cases is parallel evidence drawn from naturally occurring field counterparts. We provide a small movement in this direction by taking advantage of a unique opportunity to work with a Chinese high-tech manufacturing facility. Our study revolves around using insights gained from one of the most influential lines of behavioral research—framing manipulations—in an attempt to increase worker productivity in the facility. Using a natural field experiment, we report several insights. For example, conditional incentives framed as both “losses” and “gains” increase productivity for both individuals and teams. In addition, teams more acutely respond to bonuses posed as losses than as comparable bonuses posed as gains. The magnitude of this framing effect is roughly 1%: that is, total team productivity is enhanced by 1% purely due to the framing manipulation. Importantly, we find that neither the framing nor the incentive effect lose their significance over time; rather, the effects are observed over the entire sample period. Moreover, we learn that repeated interaction with workers and conditionality of the bonus contract are substitutes for sustenance of incentive effects in the long run. This paper was accepted by Gérard P. Cachon, decision analysis.
Reflected Knowledge and Trust in Global Collaboration
Authors: Mortensen Mark , Neeley Tsedal B. 
Published: July 2012

Scholars argue that direct knowledge about distant colleagues is crucial for fostering trust in global collaboration. However, their arguments focus mainly on how trust accrues from knowledge about distant collaborators' personal characteristics, relationships, and behavioral norms. We suggest that an equally important trust mechanism is “reflected knowledge,” knowledge that workers gain about the personal characteristics, relationships, and behavioral norms of their own site through the lens of their distant collaborators. Based on surveys gathered from 140 employees in a division of a global chemical company, we found that direct knowledge and reflected knowledge enhanced trust in distinct ways. Although both enhanced feelings of closeness with others, results indicate that direct knowledge increased focal actors' understanding of their distant colleagues, whereas reflected knowledge promoted feelings of being understood. We discuss implications of reflected knowledge to theories of trust and interpersonal dynamics in globally distributed collaboration.This paper was accepted by Jesper Sørensen, organizations.
Managers and Students as Newsvendors
Authors: Bolton Gary E. , Ockenfels Axel , Thonemann Ulrich W. 
Published: July 2012

We compare how experienced procurement managers and students solve the newsvendor problem. We find that managers broadly exhibit the same kind of pull-to-center bias as students do. Also, managers use information and task training no better than students. The performance of managers is positively affected by the level of their education and their level in the organizational hierarchy. We discuss implications for theory and for how ordering might be improved in practice. This paper was accepted by Teck Ho, decision analysis.
Knowledge Recombination Across Technological Boundaries: Scientists vs. Engineers
Authors: Gruber Marc , Harhoff Dietmar , Hoisl Karin 
Published: July 2012

Building on the seminal work of Thomas J. Allen, we contribute to the emerging microlevel theory of knowledge recombination by examining how individual-level characteristics of inventors affect the breadth of their technological recombinations. Our data set combines information from 30,550 European patents with matched survey data obtained from 1,880 inventors. The analysis supports the view that inventors with a scientific education are more likely to generate patents that span technological boundaries (in our case, 30 broad, top-level technological domains) than inventors with an engineering degree. A doctoral degree is associated with increased recombination breadth for all groups of inventors. The breadth of an inventor's technological recombinations diminishes with increasing temporal distance to his education, but the differences between scientists and engineers persist over time. Our findings provide several new insights for research on inventors, the literature on organizational learning and innovation, and strategy research.This paper was accepted by Lee Fleming, entrepreneurship and innovation.
Some investigations of the effects of core size and steel and concrete quality in short reinforced concrete columns
Authors: King J. W. H. 
Published: July 2012

Summary: The work described is a continuation of earlier work on short concrete columns, which had as its object the determination of the effect of lateral reinforcement on column strength. It was clear from this earlier work that relative core size would be likely to have a significant effect on strength, and the present investigations were initiated primarily to examine this. On the assumption that the currently accepted formula for helically bound columns had some justification for taking as one of its terms “"core area by concrete strength,” it was believed that high quality concrete would demonstrate the effect of core size better than a more ordinary concrete and a series of tests (Group I) was carried out in this way. As the tests failed to indicate any marked effect, columns (Group II) were made with normal concrete and high quality steel. To round off the work a third group was made of normal quality steel and concrete. In the main, binders were of a normal square type and of a materially constant strength, but a few were of modified shapes. As a result of the tests it has been possible to formulate general conclusions concerning the effect of core size, cover thickness, concrete and main steel strength, and core shape, to confirm the general conclusions of earlier work that binder contribution to strength was proportional to 1/pitch2 and to indicate that there is material advantage in using high quality steel as main reinforcement. Actual test loads are compared in the tables with loads calculated by a formula derived from the earlier tests, where core area was a constant proportion of the column area (51 per cent.), where concrete strength was sensibly constant, and where main steel consisted of various sizes of normal black bar. The significance of the various changes is thus revealed more clearly.
A plastic theory of design for ordinary reinforced and prestressed concrete including moment re-distribution in continuous members
Authors: Baker A. L. L. 
Published: July 2012

Summary: A general expression is derived for the ultimate strength in bending of ordinary reinforced concrete and two types of prestressed concrete beams, taking into account plasticity. A method of calculating elasto-plastic deformations is developed and applied to the problem of re-distributing bending moments in continuous members and frames.
The non-destructive testing of concrete
Authors: Jones R. 
Published: July 2012

Summary: A method is described which has been used to determine the velocity of longitudinal waves in concrete specimens by measuring the time taken for an ultrasonic pulse to travel through a known length of concrete. Results are given which illustrate the use of the method for studying the variations occurring among laboratory specimens. The value of the longitudinal wave velocity as an index of concrete quality is discussed, with reference to tests made on a variety of specimens subsequently subjected to compressive and flexural strength tests and density analysis. Deterioration of concrete quality due to freezing and thawing can be detected before superficial damage occurs. The Poisson's ratio of several types of concrete has been measured and values from 0·16 to 0·31 obtained depending mainly upon the type of aggregate.
The distribution of concrete stress in reinforced and prestressed concrete beams when tested to destruction by a pure bending moment
Authors: Prentis J. M. 
Published: July 2012

Summary: A method is given for utilizing experimental data derived from bending tests on reinforced and prestressed concrete beams to determine the stress-strain relationship for concrete. No initial assumption is made as to the shape of this curve, and the result obtained is unique for the given test data, so that the factors which govern the validity of the final result are simply the basic assumptions of the method of analysis.
Principles underlying the steam curing of concrete at atmospheric pressure
Authors: Saul A. G. A. 
Published: July 2012

Summary: This paper summarizes the conclulions drawn from experimental work carried out at the Cement and Concrete Association Research Station and elsewhere concerning the principles underlying steam curing at atmospheric pressure. It is shown that if the temperature gradient of the concrete after the time of mixing does not exceed a certain value, the concrete gains strength during and after treatment in relation to its “maturity” (reckoned in temperature-time) approximately in accordance with the same law as holds for normally cured concrete. Concrete which is raised in temperature more rapidly is shown not to obey this law, and to be adversely affected in strength at a later age. The use of the too rapid early temperature rises often employed in practice introduces various opposing variables which suggest optimum temperatures, delayed treatments and other arrangements of the curing cycle; such expediencies are unnecessary, however, if a slow initial temperature gradient is used. The paper contains tables of results supporting these conclusions, and an appendix in which a possible cause of the phenomena is suggested.
Experimental blastfurnace cement incorporating high-magnesia slag
Authors: Stutterheim N. , Nurse R. W. 
Published: July 2012

Summary: Experimental granulations have been carried out on slags from blastfurnaces employing a dolomitic burden. The resulting slags, containing 15–18 per cent MgO, were made up as Portland blastfurnace cements and standard tests were carried out. Cements of good quality were obtained, although the substitution of MgO for CaO in the slag results in a fall in strength. In spite of the high MgO contents, no periclase was formed in the slags, and the cements showed no long-term unsoundness.
Tests on end-anchored unbonded prestressed concrete beams having parabolic steel eccentricity, subject to uniformly distributed loading
Authors: Gifford F. W. 
Published: July 2012

Summary Tests were carried out on a series of four rectangular beams in which the prestressed was induced by two 5 mm wires placed in parabolic grooves cast into the sides of the beams. The loading applied was approximately uniformly distributed, and while the widths of the beams were varied, the working stress in the concrete was maintained at approximately one-quarter of the cube strength, necessitating varying initial stresses in the steel. The beams were tested to destruction, the main object being to establish the factors of safety against cracking and failure, and to obtain data in connexion with the theory of the ultimate strength of prestressed concrete beams.
The percentage voids in compacted gravel as a measure of its angularity
Authors: Shergold F. A. 
Published: July 2012

Summary The British Standard for concrete aggregates (B.S. 882:1944) distinguishes “rounded” from “angular” aggregates, but gives no method for defining or measuring different degrees of angularity. The present article describes the development of a test for this purpose. A study of the literature was followed by experimental work which showed thar the most suitable method for expressing the degree of angularity of gravels was the measurement of the proportion of voids in the single-sized aggregate when compacted in a prescribed way. This proportion was found to vary from about 33 per cent in a well-rounded beach gravel to about 45 per cent in a very angular crushed rock. The test result is expressed thus:— “Angularity number” = percentage voids — 33. The angularity number of about 100 samples of aggregate ranged from 0 for very rounded gravel to 11 for an angular crushed material, and showed good agreement with personal opinions of the relative angularity of the samples and with the compacting factor of concrete made from some of the aggregates. Full details of the method of test are given in an appendix.
Test of a prestressed concrete building frame
Authors: Shepley E. 
Published: July 2012

Summary The behaviour of a multi-storey building frame under vertical loading has been simulated in a test to destruction of a full-size replica of a single storey. Reinforced concrete columns and prestressed beams were monolithically married at the joints by in situ concrete and mild steel bars and, during the test, measurements of joint moments and span de flexions were made. The frame was designed according to elastic theory and the sections were detailed in contemporary fashion as regards working stresses in the respective components, i.e. reinforced, prestressed and composite. The test confirmed that a satisfactory design with an adequate factor of safety against collapse can be made on the basis of an elastic analysis.
A method for determining the dynamic Young's modulus of concrete specimens developed for corrosion studies
Authors: Stutterheim N. , Lochner J. P. A. , Burger J. F. 
Published: July 2012

Summary The effect of aggressive environments on concrete can conveniently be studied by observing the resultant changes in the dynamic modulus of elasticity of test specimens. An apparatus for rapid and accurate measurement of the fundamental transverse and longitudinal frequencies of a 1 × 1 × 11 in. concrete specimen is described. Typical experimental results are presented.
A variable-air-gap inductance strain gauge
Authors: Simmons J. C. 
Published: July 2012

Summary This note describes a sensitive inductance strain gauge designed for use on wet concrete test specimens. The gauge is of the variable-air-gap type and depends on the strain of the test specimen causing a change in length of a small air gap in a magnetic circuit. An a.c. bridge network and an amplifier enable the output signal to be measured by a d.c. milliameter. The sensitivity of the gauge can be varied over a wide range and, over the range of sensitivities tested, the calibration curve was sensibly linear. At maximum sensitivity strains of the order of 2 × 10−7 could be detected.
Poisson's ratio of concrete: a comparison of dynamic and static measurements
Authors: Simmons J. C. 
Published: July 2012

Summary This paper describes static and dynamic tests carried out on a series of concrete specimens to determine the values of Poisson's ratio. Three values of the ratio were determined, the static value and two values derived from the dynamic tests. Where possible the values are related to each other and to other properties of the concrete. Values of the elastic moduli determined from both types of tests are also compared. From the results of the dynamic tests an equation is derived by which the dynamic elastic modulus may be determined from measurements of the ultrasonic pulse velocity.
The effect of varying the pre-tension and area of reinforcement on the ultimate bending strength of concrete beams
Authors: Prentis J. M. 
Published: July 2012

Summary Tests on eighteen pre-tensioned concrete beams are reported. The beams were cast in groups of three, the members of anyone group differing only in the amount of pre-tension. The percentage of reinforcement varied between groups but was always sufficient to preclude failure by steel rupture. Two series of tests were made. In the first, three groups of three beams were made and tested by the author who used an extreme range of pre-tension. The second series was made and tested independently by Mr F. C. H. Nisbet, who repeated the author's tests in respect of beam dimensions and percentage of reinforcement, but who used rather higher concrete strengths and a more practical range of pre-tension.(1)* The beams were all 4 in. deep with an effective depth of 2½ in. Two widths were used: 1⅛ in. and It in. The length between supports was 45 in. and under four-point loading the central 15 in. was subjected to a uniform bending moment. Both the area of steel and the degree of pre-tension were found to have an appreciable effect on the bending strength of the beams.
A portable ultrasonic concrete-testing apparatus
Authors: Elvery R. H. , Vale D. W. 
Published: July 2012

Summary The new apparatus described is basically similar to the Road Research Laboratory ultrasonic equipment but has been designed to be more convenient for field testing work. It has been built in two separate units for easy portability and the weight has been reduced to approximately half that of the original apparatus. It is still necessary to provide an a.c. mains supply for the equipment. A number of new features have been incorporated, providing greater convenience in use and servicing.
Maturity and the strength of concrete
Authors: Plowman J. M. 
Published: July 2012

Summary The relationship between concrete strength and its maturity is examined and the datum temperature for maturity calculations determined. Strength-maturity results from varying sources are examined and a law stated relating the strength at any maturity to that at a given maturity. This law is shown to be independent of water/cement ratio, aggregate/cement ratio and cement quality. Examples of the uses of this law are given.
The minimum transverse strength of slab bridges
Authors: Morice P. B. 
Published: July 2012

Summary A theoretical analysis of the modes of failure and ultimate strength of slab bridges shows that the normal method of elastic analysis leads to a design in which the transverse flexural strength is considerably greater than that required to give a factor of safety in the structure as a whole equal to that of longitudinal elements considered alone. It is suggested, therefore, that in the design of slab bridges advantage can be taken of this by permitting moderate tensile stresses when calculating the degree of transverse prestressing required, and that in reinforced slab bridges the amount of transverse reinforcement can be appreciably reduced.
The effect of temperature on the compressive strength of concrete
Authors: Malhotra H. L. 
Published: July 2012

Summary As part of an investigation on the effect of temperature on the crushing strength of concrete, tests have been carried out using 2 in. diameter by 4 in. long specimens made with ordinary Portland cement, river sand and gravel aggregate, having various mix proportions and water/cement ratios. The crushing strength of concrete at temperatures up to 600°C was independent of the water/cement ratio used but was influenced by the aggregate/cement ratio. Concrete specimens loaded to produce normal design compressive stress during the period of heating showed less reduction in strength than specimens without imposed load. There was afurther loss in the compressive strength of the specimens when cooled after heating to a given temperature.
Site determination of friction in prestressing cables and interpretation of test data
Authors: Trimble E. G. 
Published: July 2012

Summary This paper describes tests carried out on site to determine friction loss in Freyssinet cables in lead-lined steel Kopex tube,* the results of which largely confirm some of the figures published previously by Cooley.† The tests were based on force measurements and it is shown that extension measurements may not always be reliable. It is shown also that the effect of friction may result in the cable tension at the centre-line being higher than that at the anchorages.
An approximate solution to the problem of longitudinally continuous shells
Authors: Morice P. B. 
Published: July 2012

Summary An orthogonal series of functions, described by Inglis as “basic functions”, provides the basis of a method of analysing shells with end conditions other than the usual case of simple support. Owing to the differential relations of the basic functions, it is necessary to use the Schorer shell equation. It is shown that the membrane equations and the simple edge beam analyses yield solutions compatible with that of the edge disturbance problem so that a complete shell edge beam analysis is possible.
An appreciation of the Schmidt rebound hammer
Authors: Kolek J. 
Published: July 2012

Summary The Schmidt rebound hammer is described and some theoretical aspects underlying the functioning of the hammer are discussed and supported by some experimental results. The method of performing the test and its limitations under different conditions are described. Correlations with rate of wear of concrete and compressive strength on the basis of 500 cube results are derived. The Schmidt rebound hammer is recommended for use in two categories of application—on the building site and in precast works.
A sand drier for a concrete laboratory with an Appendix on thermal performance
Authors: Hopkins H. J. , Neville A. M. 
Published: July 2012

Summary This article describes a rotary sand drier made of stock items of equipment to serve the requirements of a laboratory at Canterbury University College, Christchurch, New Zealand, in which all concrete for experimental and demonstration purposes is made with dry aggregate conforming to pre-determined grading curves. From 15 to 20 tons of aggregate are used each year.
Measurement of the thickness of concrete pavements by dynamic methods: a survey of the difficulties
Authors: Jones R. 
Published: July 2012

Summary: This note reviews the practical difficulties and errors occurring in the methods employed in determining the thickness of concrete pavements by non-destructive methods based on the propagation of sound waves in the pavement. Most of the methods give errors in the determination of the thickness of imperfectly compacted slabs when a variation of sound velocity occurs with depth in the slab, but calculations are given which show that the method based on the reflection of an ultrasonic pulse by the bottom of the slab could be made to yield accurate results should the present experimental difficulties be overcome.
The relation between the strains in the concrete and the steel in reinforced and prestressed concrete beams
Authors: Evans R. H. , Williams Alan 
Published: July 2012

Summary Information, obtained by X-ray photography, is presented on the strains in the steel and concrete and on the slip occurring in concrete beams reinforced or prestressed with various types of bar and wire. An expression is derived relating strain in the steel, virtual strain in the concrete, and slip at the steel-concrete interface. A comparison is made between strains in the concrete at the interface and at the surface. It is found that, for reinforced concrete beams, the strain at the surface is lower than the strain in the interior. The strain in the steel at the section of failure is compared with the average surface strain in the concrete at the level of the steel. The influence of several factors on this ratio is discussed. It is found that the ratio of the strain in the steel to the average strain in the concrete has a value greater than unity for reinforcement with good bond characteristics and that the ratio increases as loading increases and when the section of failure occurs at a peak in the bending moment diagram.