Abstract: Described herein are examples of improved material (and/or universal) testing machines having a lower crossbeam that may be moved via a drive system of the material testing machine. In some examples, this may be accomplished via drive shafts with different threading in upper and lower portions, and/or independent drive systems for upper and lower crossbeams. The ability to dynamically adjust (e.g., raise) the lower crossbeam may allow an operator to interact with test samples at a more comfortable height, and reduce the need for an operator to repeatedly bend and/or kneel.

Abstract: A testing machine includes a base, at least a pair of columns joined to the base and a crosshead joined to the columns at a location spaced apart from the base. At least a pair of specimen holders are provided. A first specimen holder is supported by the crosshead and faces the base, and a second specimen holder is supported by the base, the base being that portion joined to each of the columns closest to the crosshead. An actuator connected in series between one of the specimen holders and the corresponding base or crosshead. A brace connected to each of the columns and spanning between the columns, the brace being connected to each of the columns at a location along a length thereof between the base and the crosshead.

Abstract: The present disclosure discloses a temperature-controllable large-size geotechnique true triaxial multi-field coupling test system and a test method. The system includes a host loading mechanism, a deformable large-size soil box, an independent three-dimensional loading unit, a refrigeration, water and salt supplementation unit, and a soil-water-ice-salt change monitoring unit. The deformable large-size soil box is arranged on the host loading mechanism. In combination with the special structural design, monitoring is carried out by dividing a large-size soil test sample into environmental soil and a core soil region to eliminate the size effect of the test. The solution can simulate a three-dimensional stress state of the soil test sample in a three-dimensional open system. In consideration of the evolution of hydrothermal salt and three-dimensional migration of temperature, water, salt, etc. between the soil and the environment, temperature-water-salt-stress-strain multi-field coupling is realized.

Abstract: A first object for assembly with a second object, the first object comprising: a body having a first mating portion; and a first electronic element fabricated on the body; wherein the first electronic element is provided to establish an electrical coupling with a second electronic element fabricated on one of: the body and the second object, wherein a second mating portion is provided on the second object, and wherein the electrical coupling is configured to provide a measurable output for positioning the first mating portion at a desired position relative to the second mating portion according to an analysis of the measurable output against a predetermined reference output.

Abstract: An in-situ test device and method for surrounding rock strength of bolt supported roadway is provided. The test device includes a fixing mechanism, a loading mechanism, a measuring mechanism and a control system. The loading mechanism includes a hydraulic pump and a plunger pump, the hydraulic pump drives the plunger pump to work and controls the lifting speed of the loading cylinder; the measuring mechanism includes an infrared ranging unit and a wireless pressure monitoring unit; the control system controls the work of the loading mechanism and processes the monitoring data. The test device is directly installed in the roadway and fixed with the bolt. The device is loaded after leveling, the device is disassembled after the monitoring data are obtained, and the in-situ test for the surrounding rock strength of the bolt supported roadway is completed. The steps are simple and adaptable.

Abstract: The present invention discloses a double cantilever beam-encoding lead screw combined sensing tensile test method and machine. The double cantilever beam-encoding lead screw combined sensing tensile test machine comprises a main frame, a standard, a test piece and a microcomputer numerical control unit. The main frame is a force-deformation combined sensing mechanism composed of a double cantilever beam sensor, an encoding lead screw and a drive device. The double cantilever beam sensor is composed of a fixed cantilever beam sensor and a movable cantilever beam sensor. The encoding lead screw is composed of a drive lead screw and a tristate encoder. The double cantilever beam sensor matches with the encoding lead screw to achieve three functions, namely, test piece clamping, force sensing and deformation sensing, as well as to measure the size of the test piece.

Abstract: A robotic arm includes a base, a first robotic arm, a second robotic arm, a robotic hand and a cigarette holder connected in sequence. The cigarette holder includes a cigarette insertion hole and a cigarette smoking tube. The cigarette smoking tube is connected to a smoking simulator. The robotic arm further includes at least one air exhausting hole. The air exhausting hole is located around the cigarette holder and communicated with an air exhauster through an air exhausting pipe. The robotic arm swings to control the cigarette holder to carry a cigarette from a smoking position to an ash flicking position. Airflow is formed near the air exhausting hole by means of air exhaustion, so as to simulate influences of a wind speed in an outdoor environment on the columnar ash in the cigarette smoking process of the human body.

Abstract: An apparatus for determining 3D load displacement characteristics of an anatomical joint formed by a first body portion and a second body portion moveable with respect to the first body portion. The apparatus includes a first frame for receiving and securing the first body portion and a load displacement assembly. The load displacement assembly includes a first axis for alignment with a first anatomical plane of the joint, a second frame for receiving and securing the second body portion. The second frame is movable relative to the first frame. The load displacement assembly also includes a first counterweight configured to balance the weight of the second frame, a force for applying a load to the second frame, and a displacement sensor for measuring displacement of the second frame relative to the first frame upon application of the force.

Abstract: A shape memory effect measuring apparatus is provided that is useful for tensile stress, strain and recovery stress measurement. The apparatus includes a load cell, a linear variable displacement transducer, a temperature sensor, a rigid platform, a computer-based data recorder and a processing system a load frame, grips to hold sample, and a liquid bath. The liquid bath is mounted on the rigid stand platform to hold the liquid bath. A uniform temperature of liquid is attained by controlled heating and stirring arrangement. The computer-based processing system may be used to monitor and control the desired temperature of the sample. A change in length of a specimen and stress generated during expansion thereof may be recorded, from which strain and stress may be calculated using the apparatus.

Abstract: A testing apparatus includes a crosshead and a head assembly. The head assembly includes a head cover having an interior volume. An electric actuator, controls and other electric components are located within the interior volume, wherein the motor, controls and other electric components generates heat when energized. A divider within the interior volume separates a first volume from a second volume. The first volume includes the heat generating electric motor, controls and electric components and the second volume contains substantially no heat generating components. The head assembly includes at least one fan within the second volume that draws cool air from outside the head cover and forces the cool air through the second volume and into the first volume to remove heat.

Abstract: A device, assembly and method for clamping single fibers that utilizes snubbing surfaces simultaneously with magnetic gripping action are described. The device can be fabricated at miniature sizes with very low mass and volume, which are desirable requirements for testing of small fibers in highly sensitive force-transducing load frames. Advantageously, the combined use of snubbing surfaces and magnetic gripping greatly reduces the probability of slippage or fiber failure at the grip during testing.

Abstract: Systems and methods provide for testing a cement by applying force in a first direction until the first portion of the cement sample fails in compression or tension; and applying force a second direction opposite the first direction until the second portion of the cement sample fails in tension or compression.

Abstract: A compression testing assembly for compression testing of a test material includes a testing stage with a first surface and a second surface. The test material is disposed between the first and second surfaces. The assembly also includes a thickness detector that automatically detects a thickness of the test material. Moreover, the assembly includes an actuator that moves at least one of the first and second surfaces toward the other of the first and second surfaces to compress the test material to a predetermined percentage of the detected thickness of the test material. Additionally, the assembly includes a load detector that detects a compression load of the test material and that detects a change in the compression load over time.

Abstract: A method and apparatus for generating a tension wave. A beam of coherent light is directed to an absorber surface of a transducer structure. A compression wave is generated within the transducer structure. The compression wave is reflected on a reflecting surface of the transducer structure to form the tension wave. The tension wave is directed through a test object in a desired direction using a configuration of the reflecting surface relative to the test object.

Abstract: A testing machine includes a stand and a test device. The stand includes a base, box frame, a slide device driven to slide by a motor, and a control system controls the force applied on the test specimen. The test device is coupled at the slide device for performing various hardness tests consisting of Rockwell hardness test, Vickers hardness test, Brinell hardness test, micro-hardness test, and tension-compression test. The test device includes a force sensor and a data processing circuit converting an analog signal of the force sensor into digital data to interface with the control system.

Abstract: The present invention includes: a pair of columnar members 12 disposed on both sides of a specimen piece SP; a crosshead 15, bridging the pair of columnar members 12, that applies a load to the specimen piece SP by moving in a direction of a longitudinal axis of the columnar member 12 and; a movable member 31 disposed at a side of the columnar member 12, extending in the direction of the longitudinal axis and elastically supported so as to be movable in the direction of the longitudinal axis; a striker 35, integrally attached to the movable member 31 so as to be displaceable in the direction of the longitudinal direction, that is allowed to be pushed by a movement of the crosshead 15 to a position where the striker is attached; a position sensor 38 that detects a movement of the movable member 31 by being pushed by the striker 35; a limitation member 34 that limits the position where the striker 35 is attached; and an elastic member 36 that supports the striker 35 so that the striker 35 is capable of relative

Abstract: A gripper and a driving method using the same are disclosed, wherein an actuator has a configuration combined with a piezoelectric operating unit and a bending structure, whereby an amount of variation of a gap between fingers are amplified more than that of the piezoelectric operating unit by generating a movement of the fingers perpendicular to a movement direction of the piezoelectric operating unit, and wherein the gripper having arms including a strain gauge sensor can precisely measure a force applied to a micro object.

Abstract: The crosshead for a universal testing machine includes a interior face which is formed at angle to the front face which is typically about 17°. A wedge pocket is machined with walls perpendicular to the interior face, and therefore at an angle other than perpendicular to the front surface of the crosshead. This allows a rectangular steel plate to be oriented to match the machine column locations. Therefore, the material cost is significantly reduced as no special casting shape is required.

Abstract: A hybrid bioreactor for cell culture is disclosed. To simultaneously apply compressive strain for cell differentiation and shear strain for cell proliferation to cells, the hybrid bioreactor includes a plurality of reactor tube assemblies (100), a compressive strain motor (5), a shear strain motor (25), a lower anchor mount (20) having a plurality of toothed anchors (70) to respectively anchor the lower ends of the reactor tube assemblies (100) to the lower anchor mount (20), a ball screw (90) operated in conjunction with the compressive strain motor (5), an upper anchor mount (60) which engages with the ball screw (90) to vertically move upward and downward and having a plurality of compressive strain anchors (80) to anchor the upper ends of the reactor tube assemblies (100) to the upper anchor mount (60), a power transmission unit to transmit the rotating force of the shear strain motor (25) to the toothed anchors (70).

Abstract: The apparatus has an elongate and vertically running carrier (90) for pressure sensors (50), which precedes a group of levers (71 ). The cross section of this carrier (90) is arcuate, so that it has two flanks (93, 94 ). During the testing of a leg garment (80), this carrier (90) simulates the region of the shin. The apparatus has, furthermore, moldings or stays (88) which are carried by the levers and which simulate the rear face of the calf or of the thigh of a leg. The width of these stays corresponds to the width of the calf or of the thigh of a leg. The apparatus also comprises two longitudinally running groups (50) of pressure sensors, one of which is in each case assigned to outside of one of the flanks (93, 94) of the carrier (90). The leg garment (80) to be tested, in order to test it, is slipped over this apparatus in such a way that it lies on the outer faces both of the carrier (90) and of the stays and exerts pressure on the pressure sensors (51).

Abstract: A method and system are provided for obtaining force-displacement responses for a specimen or sample of material. The sample is supported with a spanning portion spanning in an environment between at least three points not in a line, wherein the points are fixed relative to each other, and wherein the spanning portion is capable of displacement relative to the points. An oscillating mechanical excitation at at least one frequency and at at least one known amplitude is applied to the spanning portion. In addition, at least one other mechanical excitation is also applied to the spanning portion independently of the oscillating mechanical excitation.

Abstract: A method for evaluating thermal fatigue resistance for a welding consumable alloy can include the following steps: placing a test specimen of a welding consumable alloy in a testing device such that a tensile load and a compressive load can be introduced to the test specimen; heating the test specimen to a first temperature; applying a compressive force to the test specimen while heating the test specimen; cooling the test specimen to a second temperature; and applying a tensile force to the test specimen while cooling the test specimen.

Abstract: A testing system includes a soft reaction structure formed by column assemblies, a base and a crosshead. Compliant devices are disposed between the column assemblies and the base and/or the crosshead to isolate interaction of these components and reduce structural vibration mode excitation.

Abstract: A method and a device for detection of physical or approximately physical bottom contact for objects, for instance fishing tackles, which are dragged closely above or on a sea bottom, said method consisting of sensoring an alteration of a force acting on a tension sensor (4) as a consequence of a mass (7) coupled to the tension sensor (4) coming into physical contact with the bottom, said alteration being used as indication of bottom contact, and that frictional forces (F2) being due to the dragging of the mass (7) along the bottom mainly are taken up by means of a tension release means (8). The device comprise the mass (7) being suspended in a tension sensor (4) in such a manner that the sensor (4) is actuated by bottom contact, and at least one tension release means (8) connected to the mass (7) and adapted to take up forces caused by dragging of the mass above the bottom.

Abstract: A beam transducer employs a linear bearing which surrounds the active element of the transducer which is the beam. One end of the bearing is welded to the inactive end of the load beam. The other end of the bearing is not welded, allowing the active end of the beam to move freely. The linear bearing eliminates friction and jamming which will cause inaccurate load measurement, but the ability to allow the active element to move freely with one end free enables the load beam sensitivity to be maximized. The free end is sealed environmentally by employing a flexible metal membrane or diaphragm which is welded between the bearing end and the load beam. This configuration provides a hermetic seal to protect the load beam and the sensitive gages which are placed on the load beam.

Abstract: Anchor chain load measurement arrangement for measuring the reactive load in structures which support an anchor chain. In one arrangement, standard resistance compression load cells are mounted directly in the load path between a chain retainer and a trunnion block. In another arrangement a non-contact sensor is positioned to measure the deflection of an inner portion of the trunnion block with respect to a supported outer portion of the trunnion block. The non-contact sensor can be based on capacitive, eddy current or optical measurement principles.

Abstract: A beam transducer employs a linear bearing which surrounds the active element of the transducer which is the beam. One end of the bearing is welded to the inactive end of the load beam. The other end of the bearing is not welded, allowing the active end of the beam to move freely. The linear bearing eliminates friction and jamming which will cause inaccurate load measurement, but the ability to allow the active element to move freely with one end free enables the load beam sensitivity to be maximized. The free end is sealed environmentally by employing a flexible metal membrane or diaphragm which is welded between the bearing end and the load beam. This configuration provides a hermetic seal to protect the load beam and the sensitive gages which are placed on the load beam.

Abstract: A load increasing in a stepped manner from an initial load is applied to a test piece (4) of material in order to examine mechanical properties of the material by applied load, but the load having a next step load added thereto is applied to the test piece after it is confirmed that the variation of strain within a unit time applied to the test piece in the load (Wn) applied in each step falls within a predetermined value whereby there are measured physical variation and time variation in the load applied in each step. The load applied to the test piece is preferably kept at a constant value and the applied load (Wn) and and time variation are preferably recorded.

Abstract: A material testing system includes a base and first and second specimen holders. A first displacement sensor measures displacement of the first specimen holder relative to the base. In addition, a second displacement sensor measures displacement of the second specimen holder relative to the base.

Abstract: A force measuring device and method for determining a force required to move a cart. The force measuring device includes a force generating device, a load member, a load cell, and a controller. The force generating device is connected to the load member and moves the load member toward or away from the cart so as to apply pushing or pulling forces to the cart. The load cell is disposed between the load member and the cart, and transmits sensed force data to the controller. During a test, the controller collects the force data from the load cell. By testing carts of various configurations under all expected loading conditions, the performance of each cart configuration can be experimentally determined. The performance data is assembled in a database to permit a user to identify an optimum cart for an intended application.

Abstract: A creep testing fixture and method for applying a precise amount of constant tensile stress to a creep test specimen to allow for precise measurement of creep in the test specimen. The fixture includes first and second mounting grips for holding opposite ends of a test specimen. A frame supports the mounting grips for relative reciprocal movement toward and away from each other. A tensile spring is connected between the first and second mounting grips. The frame subjects a test specimen held between the mounting grips to tensile stress in response to axially inward force that the tensile spring applies to the frame.

Abstract: A force measuring device and method for determining a force required to move a cart. The force measuring device includes a force generating device, a load member, a load cell, and a controller. The force generating device is connected to the load member and moves the load member toward or away from the cart so as to apply pushing or pulling forces to the cart. The load cell is disposed between the load member and the cart, and transmits sensed force data to the controller. During a test, the controller collects the force data from the load cell. By testing carts of various configurations under all expected loading conditions, the performance of each cart configuration can be experimentally determined. The performance data is assembled in a database to permit a user to identify an optimum cart for an intended application.

Abstract: A method for testing the stability of vertically braced masts wherein the relevant mast is subjected to the load of a bending force starting from a defined initial value, and increasing to a maximum pre-set testing force above its bracing, the mast thereby being laterally displaced. The load is then removed from the mast and is subjected to a restoring force which reduces to zero. The mast is evaluated in conjunction with the load removal procedure to determine damage to the mast and/or its bracing. The mast is subjected to an additional bending force in the opposite direction of the first bending force, and the load is once again removed from the mast in a second test procedure. A possible remaining displacement of the mast/bracing system is evaluated in conjunction with the highest mast loads to determine the type of possible damage to the mast.

Abstract: The present invention aim at providing a releasing/hooking force meter, which measures the releasing/hooking force of the leader pin of the magnetic tape cartridge.

Abstract: A force transducer assembly for measuring compressive and tensile loads applied to a force transmission device, the assembly includes a housing, a sleeve assembly and a sensor device. The housing has a hollow interior. The sleeve assembly is coupled within the interior of the housing. The sensor device is secured within the interior of the housing between a portion of the sleeve assembly and a portion of the housing. The sensor device includes first and second sensors each including an isolation diaphragm at least partially defining an oil-filled cavity, and a piezoresistive sensor positioned so as to be effected by a change in pressure in the oil-filled cavity. When a first force is applied to the apparatus in a first direction via the force transmission device, one of the isolation diaphragms is deflectable in response thereto, and when a second force is applied in a second direction opposite to the first direction, the other of the isolation diaphragms is deflectable in response thereto.

Abstract: A device to monitor and quantify the tension and compression forces acting on a well logging instrument string during deployment. The device eliminates the undesirable effects of downhole hydrostatic pressure on the sensors, and eliminates the need for a costly, complex, and high maintenance hydraulic pressure equalizing system in the force gage assembly. The device provides improved measurement accuracy, provides enhanced reliability and longer life of the sensors, and allows lower cost of manufacture and maintenance.

Abstract: A method and apparatus for estimating the degree of cleanliness of a substrate surface, particularly an inorganic surface used in the manufacturing of electronic components. A soft metal, eg., indium, probe is pressed against the substrate surface to be tested and then withdrawn. A tensile force, caused by the surface energies of the two materials, opposes the separation. If the inorganic surface is contaminated by any organic material, this force will be greatly affected. The tensile force is measured with a load cell and the displacement from the expected value will indicate the degree of contamination of the substrate surface.

Abstract: A force sensor has an elastically deformable carrier (10; 110) which absorbs the force to be measured and on which there are a first and a second strain measurement element (21, 31; 121, 131) arranged such that the elastic deformation of the carrier (10; 110) which is caused by the force leads to different elongations in the two strain measurement elements (21, 31; 121, 131). This difference in elongations is used as a measure for the force to be measured. The force sensor as claimed in the invention is largely immune to disruptive ambient influences such as temperature changes, electromagnetic interference, tensile, compressive and/or shearing forces in the lengthwise direction of the tube, shearing forces transversely to the lengthwise direction of the tube, etc. Wheel load scales with several force sensors as claimed in the invention have such a short response time that it enables measurement of the wheel loads of moving vehicles.

Abstract: According to the method suggested, the mast is submitted to an increasing force, and both this force and the deflection path are correlated to establish a characteristic load line. After it has been loaded, the mast is again relieved from the load, a characteristic load relief line is determined and the return force is correlated to the decreasing return path. The finds related to the mast solidity and anchorage are based on the tracing of the characteristic load relief line and the comparison with the characteristic load line.

Abstract: A circuit and method for correcting a sense signal of a sensor (100) where the sense signal is reduced by a negative nonlinear error component introduced by membrane stress in a sensor structure (101). A first transducer (103) is disposed at a location (203) having substantial bending stress to produce a sense signal having a linear component and the nonlinear error component. A second transducer (102) is disposed at a location (202) with substantially zero bending stress to produce a sense signal having the nonlinear error component but a substantially zero linear component. The sense signal from the second transducer (102) is added to the sense signal from the first transducer (103) to correct the nonlinear error for producing a linear output sense signal (VOUT) of the sensor (100) which is representative of the physical condition.

Abstract: A viscoelasticity measurement instrument having a support whose position can be varied relative to a sample holder for holding an end portion of a sample. A detection rod is resiliently held to the support, and holds a part of the sample. When a DC or AC force is applied to the detection rod, the displacement of the detection rod relative to the support is detected. The position of the support is varied or the DC force is varied to restore the displacement to zero. In this manner, the effect of the elastic constant of the support is eliminated. In one embodiment, a detection rod is support by leaf springs. Negative feedback control is utilized to return deformation of the leaf springs to zero at all times to eliminate the spring constant effect of the leaf springs. Since the average displacement of the leaf springs is zero, the positional relation between the permanent magnet and the coil forming the electromagnetic force generator varies negligibly.

Abstract: A pressure force sensor has two oppositely located connectors for a force introduction to an inside located force sensor module which emits an output signal as a function of an external pressure force, a fork arm attached to each of the connectors and having two fork ends which are offset by 90° and enclose the force sensor module, and pressure elements located between respective bases of the fork arms and a force introduction surface of the force sensor module, the pressure elements being also laterally enclosed by angled sections of the fork ends, so that pressure forces as well as tensile forces can be passed from the connectors to the force introduction surface of the force sensor module.

Abstract: Slackness of a ball spline joint which engages a first member of a circular shape and a second member fitted outside of the first member is measured by measuring a displacement of a first measurement point (P1) and a second measurement point (P2). The measurement points are set on the radial line passing through the center of the first member and the center of the spline groove. Using the distances (R1, R2) between the center of the first member and the measurement points (P1, P2), and the displacement amount (A1, A2) of the measurement points (P1, P2) under a predetermined relative torque, the slackness of the joint is calculated. By arranging the measurement points (P1, P2) on either side of the center of the first member, the effect of measurement error in the displacement amount (A1, A2) on the calculation is reduced.

Abstract: A method and apparatus or device are shown for checking the solidity of vertically anchored masts increasing tensile and compression forces which can be acquired with a force sensor are introduced into the mast above its anchoring, in order to load the mast with bending moments aligned oppositely to one another. With at least one distance sensor which can be brought to bear against the mast above the mast anchoring a lateral deflection of the mast which occurs on account of the bending moments is measured. The readings for the force F and the deflection S produced by the force and distance sensors are processed in an evaluation unit with respect to the functions f=F(S) and f=S(F), this being separately according to the courses of the functions f1 for the compression loading case f2 for the tensile loading case.

Abstract: A tube loading apparatus and method for tensile strength and leak testing an elongated, hollow tube such as a steam generator heat transfer tube of a steam generator plant. The apparatus may be used to determine the axial or compressive load placed on a hollow tube.

Abstract: The tension in an optical fiber being drawn from a preform is monitored by sensing its motion transverse to the drawing direction and analysing the sensed motion using an autoregressive time-series model to provide a power spectrum. One of the peaks of the spectrum is identified as associated with the fundamental natural frequency of the drawn fiber and the frequency of that peak is used in a calculation of the tension of the fiber.

Abstract: A multi-functional test machine is provided.

Abstract: A tensile test fixture for applying constant tensile forces to a tensile test specimen comprises two mounting grips, each mounted to one of two lever arms in a pivoted lever arm frame structure. One end of each lever arm is pivotally attached to a compression column while the other end of each lever arm is attached to one end of a force-applying assembly. The mounting grips are pivotally attached to their respective lever arms between the compression column and the force-applying assembly and are designed to hold opposite ends of a tensile test specimen. The force-applying assembly comprises stress and strain modules that are interchangeably installable into the force-applying assembly to selectively subject tensile test specimens to constant strain and constant stress.

Abstract: A material testing machine includes a support structure and a DC brushless linear motor operable to develop a force along a reaction axis. The DC brushless linear motor includes a set of magnets disposed along a line on the support structure parallel to the reaction axis. An elongated member slidably guided by the support structure on the reaction axis includes a plurality of coils proximate the set of magnets. A controller selectively energizes the coils.

Abstract: A tester for measuring a durability of a knitted yarn portion in which at least two sets of yarns, including a set of first yarns and a set of second yarns, are intersected, the tester includes: a first holding unit holding ends of the two sets of yarns at first positions that are relative to the knitted yarn portion; a second holding unit holding opposite ends of the two sets of yarns at second positions that are relative to the knitted yarn portion; and a position adjusting unit, connected to the first holding unit and the second holding unit, allowing at least one of the first positions and the second positions, relative to the knitted yarn portion, to be moved to other positions, thus varying an intersecting angle of the yarns of the knitted yarn portion.