Short Tape Research Articles

The Biomechanical Effects of Kinesiology Taping Methods on Side-Step Cutting Movements in Chronic Ankle Instability.

Background: The ankle joint is among the most vulnerable areas for injuries during daily activities and sports. This study focuses on individuals with chronic ankle instability (CAI), comparing the biomechanical characteristics of the lower limb during side-step cutting under various conditions. The aim is to analyze the impact of kinesiology tape (KT) length on the biomechanical properties of the lower limb during side-step cutting, thereby providing theoretical support and practical guidance for protective measures against lower-limb sports injuries. Methods: Twelve subjects with CAI who met the experimental criteria were recruited. Each subject underwent testing without taping (NT), with short kinesiology tape (ST), and with long kinesiology tape (LT), while performing a 45° side-step cutting task. This study employed the VICON three-dimensional motion capture system alongside the Kistler force plate to synchronously gather kinematic and kinetic data during the side-step cutting. Visual 3D software (V6.0, C-Motion, Germantown, MD, USA) was utilized to compute the kinematic and kinetic data, while OpenSim 4.4 software (Stanford University, Stanford, CA, USA) calculated joint forces. A one-way Analysis of Variance (ANOVA) was conducted using SnPM, with the significance threshold established at p < 0.05. The Origin software 2021 was used for data graphic processing. Results: KT was found to significantly affect joint angles, angular velocities, and moments in the sagittal, frontal, and transverse planes. LT increased hip and knee flexion angles as well as angular velocity, while ST resulted in reduced ankle inversion and increased knee internal rotation. Both types of KT enhanced hip abduction moment and knee adduction/abduction moment. Additionally, LT reduced the ankle joint reaction force. Conclusions: These findings suggest that the application of KT over a short duration leads to improvements in the lower-limb performance during side-step cutting motions in individuals with CAI, thus potentially decreasing the risk of injury.

Investigations of the effect of circular perforations and V-cut on SLTT in DPHE: An experimental analysis using IoT approach

The objective of this research is to explore the characteristics of the mean Nusselt number, friction factor, and enhancement efficiency in a double pipe heat exchanger. The emphasis lies in using short twisted tapes featuring round holes and a V-shaped cut. To conduct the experiment, an IoT-based DPHE setup was employed. In the experiment, various twisted tape configurations were examined to investigate their impact on heat transfer and pressure loss. These configurations included a full-length twisted tape and three short-length tapes with different perforation diameters. The full-length tape, with a twist ratio of x/ b = 4, spanned throughout length of the tube. In contrast, the plain short-length tape and modified short-length tapes, with the same twist ratio, were inserted in the section’s entrance. The shorter inserts, with a length ratio (LR = ls/lf) of 0.50, were compared to the full-length tape. The experimental findings demonstrated that the short-length tapes with LR = 0.50 consistently exhibited lower thermohydraulic performance compared to full-length inserts. Specifically, within the Re range of 4000–24,000, Nusselt numbers and friction factors for the short inserts were approximately 11%, 9.1%, and 6.1% lower, and 20.6%, 16.1%, and 11.2% lower, respectively, compared to the full-length inserts.

Numerical Study on Mechanical Behavior and Electromechanical Properties of Solder-Jointed REBCO-Coated Conductors.

As the second-generation high-temperature superconducting conductors, rare earth-barium-copper-oxide (REBCO) coated conductor (CC) tapes have good potential as high-field and high-energy superconductors. In superconducting applications, several joints are required for conjugating comparatively short REBCO CC tapes. Soldering lap joints are the simplest and most commonly applied REBCO CC joints. In addition to joint resistance, the mechanical behavior and electromechanical properties are also crucial for superconducting applications. In this paper, the electromechanical properties and mechanical behaviors of soldering lap joints at 77 K under a self-field were studied. The mechanical behavior was addressed by using a full three-dimensional multilayer elastic-plastic finite element model (FEM) with REBCO CC tape main layers and solder connecting layers. Then, the electromechanical properties were analyzed by using Gao's strain-Ic degradation general model on the basis of the FEM results. Both the mechanical behavior and electromechanical properties were verified by experimental results. The effects of soldering lap conditions including lap length, soldering thickness and lap style on the electromechanical properties and mechanical behaviors were discussed. The results indicate that shorter overlap lengths and a thinner solder can reduce the premature degradation of Ic due to stress concentrations nearby the joint edges; moreover, the irreversible critical strain is significantly higher in the back-to-back joint approach compared to the widely used face-to-face joint approach.

A Triply Linked Copper(III) Dicarbacorrole Dimer.

A triply linked dicarbacorrole dimer (7) was synthesized from a new meso-meso singly linked dicarbacorrole dimer precursor (6) via an oxidative fusion reaction by 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) in the presence of trifluoromethanesulfonic acid (TfOH). Single crystal X-ray structure of 7 adopts a flat conformation with a length as ca. 15.946 Å and a width as 6.903 Å, which can be regarded as a short carbaporphyrinoid tape. Two coordinated Cu ions keeps the +3 oxidation state in 7, as confirmed by NMR spectroscopy, single crystal X-ray diffraction and X-ray photoelectron spectroscopy (XPS). This is in sharp contrast to the Osuka's triply linked tetrapyrrolic corrole dimers, where the inner 3NH form is not stable and thus can only act as a divalent ligand. Due to the non-aromatic nature of dicarbacorrole macrocycle, the largely decreased HOMO-LUMO gap and red-shifted absorption of 7 are best ascribed to the strong electronic interaction between two dipyrromethene-type chromophores. To our knowledge, this is the first fully fused carbaporphyrinoid dimer with β-β, meso-meso, β-β triply linkages prepared to date.

Critical current degradation behavior of 7-filamentary Ba1−x K x Fe2As2 tapes under uniaxial strain

122-type iron-based superconductors (IBS) have attracted extensive attention due to their excellent performance. The 100 m class Ba1−x K x Fe2As2 (Ba-122) 7-filamentary IBS tapes were successfully fabricated by the Institute of Electrical Engineering, Chinese Academy of Sciences. In this study, we have performed tests of the 7-filamentary Ba-122 short tape samples (Bas samples) and the 100 m class 7-filamentary Ba-122 tape samples (Ba100 samples) under various kinds of strain using U-shaped bending spring devices. Both types of samples were still reversible even when the applied compressive strain reached −0.65%. In addition, the reversible tensile strain limit of the Bas and Ba100 samples were 0.25% and 0.28%, which increased to 0.38% and 0.41% after considering the effect of the cooling process.

Measurement of Shear Delamination Strength of REBCO Coated Conductors

A new test method for the measurement of shear interfacial delamination strength of Rare-earth barium copper oxide (REBCO) coated conductor (CC) tapes was implemented in this study. A novel shear specimen was designed and constructed. The shear specimen of epoxy resin was cured by three-dimensional printing technology and embedded with a short REBCO CC tape. The tape plane is parallel to the longitudinal axis of the specimen to realize pure shear load to REBCO CC tape through the universal uniaxial tensile load. The torque effect, non-interface elastic-plastic mechanical deformation and overflowed solder appearing in the traditional testing method are omitted. The experimental results show that the valid shear delamination strength is from 10.30 MPa to 11.98 MPa with the average value of 11.27 MPa, indicating the serious scattering of the tested data in traditional testing methods is eliminated. Through the analysis of delaminated interfaces morphology and the energy dispersive spectroscopy, it is observed that the interface delamination mainly occurs within the REBCO superconducting film itself, and a small portion of buffer layers are also peeled due to the brittle nature. In addition, based on the analysis of invalid data and the corresponding morphology after delamination, it is shown that the initial defects and failures significantly affect the experimental data, resulting in a lower testing value than the real shear interfacial delamination strength.

Correlation of Isokinetic Testing and ACL Failure With the Short Graft Tape Suspension Technique at Six Months

PurposeThe objective of this study was to correlate the data of the 6-month postoperative isokinetic muscle evaluation before resuming sports activities with the occurrence of ACL reconstruction rerupture after semitendinosus short graft.MethodsFrom 2015 to 2018, all patients who were operated for an ACL reconstruction with a short semitendinosus autograft (TLS System) and who performed isokinetic tests on dynamometer at their 6th postoperative month were included in this study. The follow-up was prospective with the measurement of epidemiological, radiographic, and isokinetic parameters at 6 months of the ACL reconstruction. The cohort was divided into 2 groups: one group without an ACL reconstruction rerupture (Group 1) and the second group with a rerupture (Group 2).ResultsOne hundred and four patients were analyzed with an average follow-up of 42.3 months (Minimum: 24; Maximum: 63.5), of which 11 patients (10.6%) had an ACL reconstruction rerupture. Group 1 consisted of 93 patients with an average age of 26.5 ± 9.0 years old who did not have an ACL reconstruction rerupture with an average follow-up of 41.6 ± 12.1 months. Group 2 consisted of 11 patients with an average age of 22.7 ± 6.1 years old, who had an ACL reconstruction rerupture with an average follow-up of 44.8 ± 11.3 months. Concerning extension force recovery, the ratio between operated and healthy knee was 81.8% ± 32.0 for Group 1, and 53.4% ± 20.6 for Group 2 (P = .035). A statistically significant difference was also found (P = .0017) during 60°/s flexion isokinetic test between the two groups.ConclusionsThis study revealed a significant link between muscle weakness in flexion and extension during 60°/s isokinetic test at 6 months of ACL reconstruction and semitendinosus autograft rerupture. Patients with an ACL reconstruction retear had inferior muscle dynamometric recovery results at 6 months before resuming sports activities.Level of EvidenceLevel III, prognostic, retrospective cohort study.

Heat Enhancement Effectiveness Using Multiple Twisted Tape in Rectangular Channels

Heat enhancement and heat removal have been the subject of considerable research in the energy system field. Flow-through channels and pipes have received much attention from engineers involved in heat exchanger design and construction. The use of insert tape is one of many ways to mix fluids, even in a laminar flow regime. The present study focused on the use of different twisted tapes with different pitch-to-pitch distances and lengths to determine the optimum design for the best possible performance energy coefficient. The results revealed that twisted tape of one revolution represented the optimal design configuration and provided the largest Nusselt number. The length of the tape played a major role in the pressure drop. The results revealed that the insertion of a shorter twisted tape can create mixing while minimizing the changes in the pressure drop. In particular, the best performance evaluation criterion is found for a short tape located towards the exit of the channel. The highest performance energy coefficient was obtained for the half-twisted tape for a Reynolds number varying between 200 and 600.

Kinesiology tape length and ankle inversion proprioception at step-down landing in individuals with chronic ankle instability

ObjectivesTo determine the effect of different lengths of kinesiology tape (KT) on ankle inversion proprioceptive performance in individuals with or without chronic ankle instability (CAI). DesignA repeated measures study. MethodsFifteen participants with unilateral CAI and fifteen participants with no CAI volunteered. The Ankle Inversion Discrimination Apparatus for Landing (AIDAL) was used to measure ankle proprioceptive acuity. All participants were tested under four KT conditions: no tape (baseline), short tape length (only foot and ankle complex involved), mid length (below the knee) and long length (above the knee) taping. After the baseline test, participants underwent the 3 different taping tests in a random order. ResultsRepeated measures ANOVA indicated that, compared to those without CAI, individuals with CAI performed significantly worse across the 4 different conditions (F = 8.196, p = 0.008). There was a significant KT main effect (F = 7.489, p < 0.001) and a significant linear effect (F = 17.083, p < 0.001), suggesting that KT significantly improved ankle proprioceptive performance in landing, and with longer tape length there was greater proprioceptive enhancement. Post-hoc analysis showed that for the CAI group, both mid length (p = 0.013, 95%CI = −0.063, −0.009) and long length (p = 0.010, 95%CI = −0.067, −0.011) taping can significantly improve ankle proprioceptive performance compared to no tape, whereas for the non-CAI group, ankle proprioceptive acuity was significantly improved only with long length taping (p = 0.007, 95%CI = −0.080, −0.015). ConclusionsKT can be used to improve ankle inversion proprioceptive performance during landing in both individuals with and without CAI and increasing tape length may achieve greater proprioceptive improvement.

Performance testing of the iron-based superconductor inserted coils under high magnetic field

The iron-based superconductor (IBS) is considered to have a great potential application under high magnetic field. It is one of the important steps to carry out the research on high magnetic field IBS inserted coil in order to promote the practical application of IBS. We developed a type of Ba122 single and double pancake inserted coils with 35 mm outer diameter, and its performance has been tested at 4.2 K in the background magnetic field of 30 T, in contrast, the transport critical current (Ic) of 30mm short tape form the same batch was measured at 4.2 K in the background magnetic field of 30 T. In this paper, design, manufacturing and heat treatment of this coils are introduced in brief, and performance testing of this coils, as well as the analysis of test results, are presented in detail. The results show the single and double pancake inserted coils can carry high transport current at 30 T background magnetic field.

Self-Reinforced Polypropylene Composites based on Discontinuous Tapes - An Experimental and Numerical Study of the Influence of Tape Length

The creation of highly oriented, coextruded polypropylene (PP) tapes allows the production of recyclable self-reinforced polypropylene (SRPP) or all-PP composites, with a large temperature processing window and high volume reinforcement content (sim90%). The objective of this research is to assess the performance potential of SRPP composites based on discontinuous or short tapes. For this, the critical tape length for effective mechanical reinforcement of aligned discontinuous PP tapes was determined, while the stress transfer from PP matrix to PP tape was investigated in single tape model composites in combination with an optical strain mapping technique. Mechanical behaviour of both single tape as well as aligned tape model composites was evaluated using finite element analysis (FEA) and used to predict the properties of randomly oriented short tape composites. These discontinuous tape SRPP composites may be of interest from a manufacturing as well as recycling point of view. In terms of manufacturing, such systems are of interest as they may show improved formability during stamping or compression moulding operations while from a recycling point of view it would allow the re-use of production waste like cuttings of fabrics or tapes.

Short and spaced twisted tapes to mitigate fouling in tubular membranes

Static mixers are an efficient means to mitigate membrane fouling as they deflect the fluid, thus increasing the shear rate at the membrane surface and enhancing back-transport of rejected matter. However, inserting static mixers in the flow channel of a membrane imposes an additional pressure drop. To decrease this detrimental effect of static mixers, we shorten twisted tape mixers and investigate how this shortening translates into a reduction of fouling mitigation. We follow two approaches known from heat transfer enhancement: i) shorten the total length of the twisted tape and ii) use regularly spaced short twisted tape elements which are kept at their position by smooth rods placed in between the twisted elements. Computational fluid dynamics (CFD) is applied to analyze the flow pattern, the shear rate at the membrane and the resulting pressure drop. The results allow for the selection of modified twisted tape mixers with lower pressure loss, but sufficient flow properties for fouling mitigation. The most promising mixer designs were selected according to the CFD study, 3D-printed, and their fouling mitigation effect experimentally investigated using silica suspensions. Additionally, the effect of foulant concentration in this system is analyzed. For low silica concentrations (0.03g/L) the short and spaced twisted tapes mitigate fouling as efficiently as the full-length twisted tape. At high silica concentrations and fluxes, the full-length mixer mitigates fouling more strongly than the short and spaced twisted tapes. However, the modified twisted tapes prove to be more energy-efficient up to a certain fouling exposure.

Study on Electromechanical Properties of Solder Jointed YBCO Coated Conductors With Etched Copper Stabilizer Under Axial Tension

The YBa2Cu3O7-x (YBCO) coated conductor (CC) is one of the most promising superconducting materials because of their high critical current (Ic) and low dependency of the Ic on the external magnetic field. For superconducting applications, a large number of joints are required to join relatively short YBCO CC tapes. In this paper, we study the electromechanical behavior of lap-jointed YBCO CC tapes fabricated by etching Cu stabilizer at its service temperatures (77 K) under self-field. The effects of etching Cu stabilizer on Ic and joint resistance (Rj) of YBCO CC tapes were discussed. The Rj was reduced and the Ic values of the joints are consistent with the parent CCs tape by etching the Cu stabilizer. Preferable electrical properties under applying axial tension are achieved and proved by the axial tension tests and finite element simulations. This fabrication technique is a unique practicable solution to reduce joint resistance for YBCO CC tapes with thicker metal stabilizing layers and improving electromechanical performance in second generation high temperature superconductor (2G HTS) devices.

Bending properties of solder joint of YBCO coated conductors by etching copper stabilizer

The YBa2Cu3O7−x coated conductor (YBCO CC) is one of the most promising superconducting materials for magnet applications because of its high critical current (Ic) and low dependency of the Ic on the external magnetic field. For magnet applications, plenty of joints are required to meet the connection of relatively short YBCO CC tapes. The bending properties of the joints inevitably become one of the critical factors that determine the performance of the superconducting magnet. In this paper, we fabricated the joints of YBCO CC tapes by etching Cu stabilizer and studied their bending properties under various bending diameter at 77 K and self-field. Compared with the soldering joint, lower joint resistance (Rj) and preferable electrical properties under applying various bending deformation were achieved and proved by the bending strain tests and finite element simulations. This fabrication technique is a unique practicable solution to reduce the Rj and improve the bending properties for the joints of YBCO CC tapes with thicker metal stabilizing layers in second generation high temperature superconductor (2G HTS) applications.

Advance and challenge of secondary-generation high- temperature superconducting tapes for high field applications

High-field magnet application is one of most driving forces for the development of high temperature superconducting (HTS) materials. Recently, the magnet consisting of ReBa2Cu3O7- δ based coated conductors (RE123, also called as secondary-generation high-temperature superconducting tapes, 2G-HTS) has exhibited the magnetic field as high as 26.4 T, over than the limit of conventional NbTi-Nb3Sn magnets. As well, an overall superconductor magnet consisting of a 2G-HTS magnet inserted into the background with low temperature superconducting magnetic field of 17 T gave rise to the magnetic field up to 32 T, reaching a new world record with regard of all superconductor magnets. In reality, these breakouts take place thanks to the latest advances in practical HTS materials, showing the promising future for power applications. The great advantages and promising prospects of RE123 coated conductors over than other practical superconducting materials have spurred the related researches and rapid development of this field worldwide recently. The further development, however, will depend on the fundamental properties, producing yield, and optimum performance/price etc. In the present paper we give a brief introduction to RE123 coated conductor and its typical structure, as well as main technical routes for the scale-up preparation. We introduce the status and development for RE123 coated conductors around the world, including the existing research institutions and technologies they employed. In past decade, people have tested a variety of thin film techniques to realize the biaxial textured RE123 coated conductors epitaxially grown on flexible metallic tapes. For the most institutions working on the preparation of RE123 coated conductor, both IBAD and RABiTS have been used as popular technical routes due to their availability of long textured substrates, the feasibility of controlled buffer growth and the potential for cost-effective processing. At the same time, various thin film coating techniques including sputtering, pulse laser deposition (PLD), metallorganic chemical vapor or solution depositions (MOCVD, MOD) are employed to prepare the coated conductors for both buffer layers and superconducting layers. Particularly, some emerged MOD technologies for preparing superconducting layer with organic addition into the precursor solution or reduced fluorine content precursor solution have been addressed, due to their great potential for a cost-effective and rapid technical route to prepare RE123 coated conductor. It is also demonstrated that the considerable efforts for artificial flux pinning in RE123 coated conductor by introducing nanoparticles and substrate surface decoration have effectively improved the J c value of RE123 under applied magnet field. The thickness effect of 2G-HTS is also an important issue, because in most case the critical current density would decrease while the thickness of superconducting layer increases. Such an effect may be suppressed with controlled techniques and microstructures or compositions. The coated conductors may maintain good biaxial texture as the thickness of superconducting layer increase from 1 to 5 μm, leading to huge increase in current-carrying capability of resultant 2G-HTS tape. It is believed that the mechanical properties of 2G-HTS tape are better than 1G-HTS tape, which is very important during the magnet coil winding. Excessive stress relief or Lorentz force would make coils split or deformed. To improve the anisotropy and mechanical properties, people have designed various types of practical conductors with RE123 tape stacks or metal tubes covered. Moreover, the welding technique of 2G-HTS tape is investigated due to importance on improving the usage rate of short tapes. In summary, the present review introduces the state of the art of 2G-HTS tape and relevant key science and technical issues, including the technical routes, artificial flux pinning, field dependence and thickness induced degradation of critical current density, joint technologies, as well as power applications, especially in the field of HTS magnet.

Effect of decaying swirl flow on tubular turbulent heat transfer enhancement by using short length helical tapes

This study deals with an experimental investigation on turbulent thermal-hydraulic performances in a plain tube (PT) mounted with swirl flow devices of short length helical tapes (SL-HTs). The heat transfer experiments were conducted at constant heat flux wall conditions while the pressure drop tests were performed at iso-thermal wall conditions. Effects of Reynolds number (Re) at 5000–19,000, tape length ratios (L/D) at 31.034–46.552, hole diameter ratios (W/D) at 0.276–0.414 and pitch length ratios (P/D) at 1.034–1.724 were explored by employing air as working fluid. The main findings are that the Nusselt number (Nu) and friction factor (f) in the PT inserted with SL-HTs could be enhanced by around 1.58–2.64 times and 4.72–16.26 times respectively in comparison with the alone use of PT. The obtained information also provides that both the Nu and f increase with increasing L/D, decreasing W/D and decreasing P/D while the PEC increases as L/D and P/D increase. In addition, the maximum PEC of about 1.17 is gained by the SL-HT at Re=5971, L/D=46.552, W/D=0.276 and P/D=1.724. The comparisons with some previous studies indicate that the SL-HTs hold certain competitive advantage. At last, the thermal-hydraulic characteristics correlations are developed with Re, L/D, W/D and P/D and the deviations from the experimental values are within ±5% for Nu and ±9% for f.

Evaluation of Clinical Outcome and Risk Factors for Failure of Single-incision Midurethral Short Tape Procedure (Solyx Tape) for Stress Urinary Incontinence

To evaluate the clinical outcome and identify risk factors for failure of the Solyx (Boston Scientific Corporation, Marlborough, MA) single-incision sling (SIS) in the treatment of urodynamic stress incontinence (USI). A retrospective observational study (Canadian Task Force classification II-2). A tertiary referral center. Patients diagnosed with USI without needing concurrent procedures that underwent continence surgery using the Solyx SIS from February 2015 to May 2017. Anti-incontinence surgery. The primary outcome of this study was the rate of objective cure defined as the absence of demonstrable leakage of urine on the cough stress test and a 1-hour pad test weight of less than 2g. The secondary outcome was the rate of subjective cure defined as a negative response to Urinary Distress Inventory question 3 (no leakage on coughing, sneezing, or laughing) and the identification of the different risk factors of cure failure. A total of 113 patients were evaluated in the study. Postoperative USI and the 1-hour pad test significantly improved from 24.2 ± 26.9 gm (range, 19.1-29.3) to 2.5 ± 8.7 gm (range, 0.9-4.2); p <0.001 through 1 year. Data analysis showed an objective cure rate of 90% (102/113) and a subjective cure rate of 86% (97/113). USI recurred in 11 patients with no repeat surgery done becausesymptoms were tolerable to the patients. No patient had bladder outlet obstruction. Peak flow rates 23.7 ± 9.1 ml/s (20.0-27.4) and residual urine volume 38.5 ± 25.8 ml (29.8-47.2) were within normal limits with no significant changes. Previous anti-incontinent surgery, previous prolapsed surgery, intrinsic sphincter deficiency, maximum urethral closure pressure <40cm H2O, and neurogenic disease were significant risk factors for sling failure. Subjective assessment on the quality of life significantly improved (p <0.001). The Solyx SIS is an effective and safe treatment option for women with USI, showing high objective and subjective cure rates with a low incidence of complications 1 year after treatment. The identified independent risk factors forfailure are related to poor urethral function and previous pelvic reconstructive surgery.

Influence of High-Thermal-Conductivity Plastic With Negative Thermal Expansion Coefficient on Cooling Performance in Conduction-Cooled HTS Coils

We evaluated an insulative-high-conduction plastic (IHCP) sheet, which had high thermal conductivity perpendicular to its plane, as an electrical insulation sheet in a high-temperature superconducting (HTS) coil. Thermal conductivity of the IHCP was measured at cryogenic temperatures and was found to be 20–40 times higher than that of a glass-fiber-reinforced plastic (GFRP). Next, the thermal strain of the IHCP was measured, and a negative thermal expansion coefficient was found along the fiber direction. The IHCP expanded to produce a strain of approximately 0.4% during cooling from room temperature to liquid nitrogen temperature. Finally, a short HTS tape was sandwiched by the IHCPs and was quenched with a local heater placed on the tape. The time required for quenching with the IHCP was several times longer than that with the GFRP. From numerical simulations of the quench tests, the IHCP's thermal contact resistance with the HTS tape was estimated to be approximately 35–40% lower than that for the GFRP. We think the IHCP is effective for increasing the thermal stability of an HTS coil.

The Influence of Local Critical Current Degradation on the Quench Characteristics of GdBCO Tapes and Coils

We experimentally investigated the influence of local critical current degradation on the thermal and electromagnetic behavior around the local degradation region and the time-dependent characteristics of the voltage across it. The local critical current degradation was produced by cutting a part of the width of a piece of GdBCO tape. The current that caused the tape to burn out and the voltages across the degradation region were measured in short tape samples and pancake coils made using GdBCO tape. In a sample without copper stabilizer covered with Styrofoam, the voltage rapidly increased over a short time period and the sample burned out soon after the operating current exceeded the local critical current. On the other hand, the tape with the copper stabilizer cooled by an LN 2 was able to stably maintain the voltage even when the operating current largely exceeded the local critical current. The current sharing effect of the copper stabilizer greatly contributed to an improvement in stability because the current sharing effect was much larger than the LN2 cooling effect. The cooling effect from the top and bottom surfaces of the coil was also important and should be improved upon as much as possible to suppress the temperature rise during coil excitation. The heat transfer effect in the radial direction between coil layers was smaller than the LN2 cooling effect.

Amicus Brief in Fox News v. TVEyes

The district court’s holdings dramatically expanded the fair use doctrine contrary to the express intent of Congress and inconsistent with existing precedent. TVEyes copies thousands of hours of entertainment, news, sports and other television programming twenty-four hours a day, seven days a week without permission or payment to authors and sells it to business subscribers for further copying and distribution at a fee of $500 per month. TVEyes and its amici attempt to excuse this copyright infringement by falsely characterizing the service as “media monitoring.” (Id.) That characterization is wrong and does not justify the holdings below. Congress thrice rejected requests to add media monitoring to the preamble of Section 107 of the Copyright Act. Instead, Congress enacted a limited alternative in Section 108, allowing libraries and nonprofit archives to engage in certain copying and archiving of works. By choosing not to include media monitoring among the enumerated examples in section 107, Congress struck the important balance between copyright holders’ interests and the general public’s interests in section 107. It is not the courts’ role to legislate or bypass Congressional intent. For this reason alone, the district court’s holdings that considered content-delivery features of TVEyes’ service fair use must be reversed. Moreover, any definition of TVEyes as a “media monitor” is a misnomer. TVEyes goes far beyond the media monitoring that was contemplated and rejected by Congress as potentially eligible for the fair use defense. At that time, a media monitoring service would give a client a short analog VHS tape that was hard to reproduce. Now, TVEyes provides subscribers unlimited digital content and encourages further distribution of works by its clients. TVEyes likewise does not qualify for the more limited non-profit archival protections in Section 108 of the Copyright Act. TVEyes is an expensive, for profit, business-to-business service that copies and digitally distributes copyrighted content from every cable channel around the clock and therefore does not meet the either the threshold requirements of Section 108 or the specific requirements of the exceptions contained therein. In addition, TVEyes’ wholesale copying of thousands of hours of television programming does not fall within the contours of the fair use doctrine as consistently applied by this Court and others to media monitoring services. Nor do this Court’s decisions in Author’s Guild v. Google, Inc. (Google Books) and Author’s Guild v. HathiTrust (Hathitrust) support the result reached below. Setting aside amici’s views on those cases, TVEyes’ service is wholly different from the services at issue in those cases. The service at issue in Google Books was a free service provided to the public for research purposes that incorporated measures intended to ensure that users could not obtain the full value from a work (whether that be the entire work or a key portion of a work like a travel guide or recipe book) via the search function. Likewise, Hathitrust involved a service displaying mere word search term results of copyrighted works. By contrast, TVEyes’ service is designed to replace the original source of the work or licensed distributors of the work. The district court erred in determining otherwise and should be reversed.