• Clinics in Shoulder and Elbow
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• v.17 no.4
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• pp.159-165
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• 2014

Background: Kirschner's wire (K-wire) transfixation and locking hook plate fixation techniques are widely used in the treatment of acute acromioclavicular joint (ACJ) dislocation. The purpose of this study was to compare the clinical and radiologic outcomes between K-wires transfixation and a locking hook plate fixation technique. Methods: Seventy-seven patients with acute ACJ dislocation managed with K-wire (56 shoulders) and locking hook plate (21 shoulders) were enrolled for this study. The mean follow-up period was 61 months. Results: At the last follow-up, the shoulder rating scale of the University of California at Los Angeles (UCLA) was higher in patients treated with locking hook plate than with K-wires ($33.2{\pm}2.7$ vs. $31.3{\pm}3.4$, p=0.009). In radiologic assessments, coracoclavicular distance (CCD) (7.9 mm vs. 7.7 mm, p=0.269) and acromioclavicular distance (ACD) (3.0 mm vs. 1.9 mm, p=0.082) were not statistically different from contralateral unaffected shoulder in locking hook plate fixation group, but acromioclavicular interval (ACI) was significant difference. However, there were significant differences in ACI, CCD, and ACD in K-wire fixation group (p<0.001). Eleven complications (20%) occurred in K-wire transfixation group and 2 subacromial erosions on computed tomography scan occurred in locking hook plate fixation group. Conclusions: ACJ stabilization was achieved in acute ACJ dislocations treated with K-wires or locking hook plates. Locking hook plate can provide higher UCLA shoulder score than K-wire and maintain CCD, and ACD without ligament reconstruction. K-wire transfixation technique resulted in a higher complication rate than locking hook plate.

• Progress in Superconductivity
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• v.13 no.2
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• pp.111-116
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• 2011

Since superconducting wires have no resistance, electromagnets based on the superconducting wires produce no resistive heating with DC current as long as the current does not exceed the critical current of the wire. However, unlike resistive wires, superconducting wires exhibit AC heat loss. Embedding fine superconducting filaments inside copper matrix can reduce this AC loss to an acceptable level and opens the way to AC-capable superconducting coils. Here, we introduce an easy and accurate method to measure AC heat loss from sample superconducting coils by measuring changes in the rate of gas helium outflow from the liquid helium dewar in which the sample coil is placed. This method provides accurate information on total heat loss of a superconducting coil without any size limit, as long as the coil can fit inside the liquid helium dewar. With this method, we have evaluated AC heat loss of two superconducting solenoids, a 180-turn solid NbTi wire with 0.127 mm diameter (NbTi coil) and a 100-turn filamented wire with 1.4 mm diameter where 7 NbTi filaments were embedded in a copper matrix with copper to NbTi ratio of 6.7:1 (NbTi-Cu coil). Both coils were wound on 15 mm-diameter G-10 epoxy tubes. The AC heat losses of the NbTi and NbTi-Cu coils were evaluated as $53{\pm}4.7\;{\mu}W/A^2Hzcm^3$ and $0.67{\pm}0.16\;{\mu}W/A^2Hzcm^3$, respectively.

• Electrical & Electronic Materials
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• v.8 no.4
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• pp.478-486
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• 1995

Cu/NbTi multilayer thin films and superconducting wires were fabricated and heat treated with conventional annealing and analyzed by differential scanning calorimetry (DSC) as a basic study for the enhancement of Jc. Interfacial reactions of Cu/NbTi multilayer thin films and superconducting wires were investigated with optical microscope, SEM, and XRD. According to the effective heat of formation (EHF) model, CU$\_$3/Ti was predicted as a first phase. However, considering the crystalline structure and thermodynamics, CuTi was predicted as a first phase. According to the results of DSC and XRD, CU$\_$2/Ti was found to be the first phase, followed by the formation Of CU$\_$4/Ti. The difference in first crystalline phase between the experimental result and the predicted one was discussed. In case of Cu/NbTi superconducting wires, the compounds formed at the Cu/NbTi interface grew with annealing time and the amount of compounds formed in Nb-47wt%Ti alloy was larger than that in Nb-50wt%Ti alloy. It seemed that the incubation time for the formation of compounds in Nb-50wt%Ti alloy was longer than that formed in Nb-47wt%Ti alloy. Also, the diffusion was the rate controlling step for the growth of compounds in all specimens. These compounds were formed at 500-600.deg. C for I hour annealing and, thus, the drawing time below I hour must be required to minimize the growth of compounds for the enhancement of Jc.

• Progress in Superconductivity
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• v.12 no.2
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• pp.75-81
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• 2011

We report on the progress that has been made in developing $MgB_2$ superconducting wires and tapes for commercialization and research efforts. A number of techniques have been developed to overcome the obstacle posed by the poor critical current density ($J_c$) of pristine $MgB_2$. Chemical doping has proved to be the effective way to modify and enhance the superconducting properties, such as the $J_c$ and the irreversibility field ($B_{irr}$). More than 100 different types of dopants have been investigated over the past 8 years. Among these, the most effective dopants have been identified to be SiC and malic acid ($C_4H_6O_5$). The best results, viz. a $B_{irr}$ of 22 T and $J_c$ of $30,000\;A{\cdot}cm^{-2}$ at 4.2 K and 10 T, were reported for malic acid doped $MgB_2$ wires, which matched the benchmark performance of commercial low temperature superconductor wires. In this work, we discuss the progress made in $MgB_2$ conductors over the past few years at the University of Wollongong, Hyper Tech Research, Inc., and Ohio State University.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.26 no.3
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• pp.199-205
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• 2013

In this study, the methodology for the fatigue life prediction using finite element method(FEM) in wire, bundle and assembly level of the wire harness system and the development of the fatigue life test machine for the numerical analysis are investigated. To obtain stress-life(S-N) histories of the componential wires of the system, five kinds of wires are prepared and applied to the repeated bending motion using developed fatigue life test equipment. Equivalent model of the wire from the rule of mixtures theory is used for the material modeling of sheath and wire core combination. Contact conditions among the wires, taping conditions are established through the bundle level test and numerical bundle analysis. Wire and bundle level results are adopted for the assembly level analysis. For the assembly level analysis, real wire harness system including bundle and grommet is numerically modeled and applied contact condition between wires with real opening motion. The fatigue life more than 700,000 cycles of the assembly is obtained from the FEM, and it is confirmed that the result has good agreement with the experimental result.

• Superconductivity and Cryogenics
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• v.20 no.2
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• pp.15-22
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• 2018

The present article briefly overviews the plan for a new project on joint technology for HTS wires/cables and describes the development plan for the world's highest field NMR magnet, which is a major development item in the project. For full-fledged social implementation of superconducting devices, high temperature superconducting (HTS) wire is a key technology since they can be cooled by liquid nitrogen and they can generate a super-high magnetic field of >>24 T at liquid helium temperatures. However, one of the major drawbacks of the HTS wires is their availability only in short lengths of a single piece of wire. This necessitates a number of joints being installed in superconducting devices, resulting in a difficult manufacturing process and a large joint resistance. In Japan, a large-scale project has commenced, including two technical demonstration items: (i) Development of superconducting joints between HTS wires, which are used in the world's highest field 1.3 GHz (30.5 T) NMR magnet in persistent current mode; the joints performance is evaluated based on NMR spectra for proteins. (ii) Development of ultra-low resistive joints between DC superconducting feeder cables for railway systems. The project starts a new initiative of next generation super-high field NMR development as well as that of realization of better superconducting power cables.

• Archives of Plastic Surgery
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• v.38 no.1
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• pp.102-104
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• 2011

Purpose: The standard treatments of hand fractures today are fixations by K -wires, metal plates, wires and lag screws. But it is very difficult to reconstruct fractures by placing implants into small bony fragments especially in the comminuted fractures and intra-articular fractures. This paper describes a simple method of reconstruction with Histoacryl$^{(R)}$ for comminuted and intra-articular fractures in hands. Methods: 2 cases with comminuted and intra-articular fractures by crushing injury were reconstructed with Histoacryl$^{(R)}$. We performed applying Histoacryl$^{(R)}$ with swab on the bone cortex carefully to avoid Histoacryl$^{(R)}$ infiltrating into the medulla. We could rearrange and fixate bony fragments using only Histoacryl$^{(R)}$, in addition, metal plates, K-wires, wires, and lag screws could be used for secondary fixation if needed. Results: Post-operative X-ray finding of 2 patients assured that the bony fragments of the hand fractures maintained their original positions. Significant displacement and deviation, infection, nonunion, and malunion during the follow-up period were not observed. Conclusion: This study showed the possibility of using Histoacryl$^{(R)}$ in addition as a simple method of fixation in the comminuted and intra-articular hand fractures.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.1311-1320
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• 2000

In this study, shape memory alloy(SMA) wires and piezoceramic actuators(PZT's) are employed in order to generate higher modes on the beam deformations. Compressive force is generated and applied to the beam by the pre-strained SMA wires attached at both ends of the beam. PZT's apply concentrated moments to several locations on the beam. Combinations of the compressive force and concentrated moments are investigated in order to understand the higher-mode deformation of beams. The first desired mode shape is obtained by controlling the temperature of the SMA wires. The first and third mode shapes are performed experimentally by heating SMA wires up to phase transformation temperature. The adaptive wing is defined as a wing whose shape parameters such as the camber, wing twist and thickness can be varied in order to change the wing shape for various flight conditions. In this research, control of the camber has been studied. The wing model consists of three plates and many ribs. Two of the plates are placed parallel to each other and they are clamped at one edge. Third plate connects the other edges of the parallel plates together. Each rib is made of SMA wire and connected to the parallel plates. It generates concentrated force and applies to the plates in oblique directions. The PZT's are bonded onto the plates and exert concentrated moments upon the plate at several locations. The object of this research is to generate various shape of wing by combining the concentrated forces and moments.

• The korean journal of orthodontics
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• v.20 no.2
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• pp.381-390
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• 1990

The purpose of this study was to evaluate the effects of heat treatment on mechanical properties in $0.016^{{\prime}{\prime}}{\times}0.022^{{\prime}{\prime}}$ blue Elgiloy wires and to measure the amounts of nickel and chromium released from the wires in artificial saliva. Ultimate tensile strength, yield strength and elongation were measured with universal testing machine (Instron). and the amounts of nickel and chromium released from the sample were measured with atomic absorption spectrophotometer after one week immersion in the artificial saliva. Ultimate tensile strength and yield strength were progressively increased below $1000^{\circ}F$, but elongation was decreased. And the results were reversed above $1100^{\circ}F$. After heat treatment of the sample for 9 minutes at $1000^{\circ}F$, the maximum tensile strength and yield strength were $213.6kg/mm^2$, $140.1kg/mm^2$, respectively. Both tensile strength and yield strength were decreased progressively above $1100^{\circ}F$. Elongation was appeared the minimum value (8.6%) after heat treatment for 9 minutes and 12 minutes at $1000^{\circ}F$. There was a pronounced increase in nickel and chromium liberation with increasing time and temperature. The maximum amounts of nickel and chromium released form the sample were $4.947{\mu}m/cm^2$, $3.088{\mu}g/cm^2$, respectively after heat treatment for 12 minutes at $1300^{\circ}F$. Heat treatment is applied to orthodontic wires, especially cobalt-chromium alloys, for the purpose of stress-relievning and hardening. When the heat-treatment of orthodontic wires, the heating procedure should be well controlled in order to have no effect on corrosion resistance and mechanical properties.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.31 no.1B
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• pp.19-25
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• 2006

It's for USB to be used more frequently than another I/O devices. The Universal Serial Bus is the most successful interface in PC history. It's already the do facto interconnect for PCs, and has proliferated into consumer electronics(CE) and mobile devices as well. USB has built on many killer applications, many CE devices, many interfaces. The tangle of wires among the number of devices in your home demands wireless technology. If our devices is unwired, it solves the tangle of wires. In this paper we want to use Legacy USB functionalities, portabilities, multimedia capabilities with wireless interconnection. This paper is related to a study of USB implementation without wires. This paper is related to make the hub function of USB cordless, so it will connect host with devices without wires. In case making USB wireless, it must support the above functionalities. Moreover, It needs the data structure and the resources for host functionalities, e.g. ETD(Endpoint Transfer Descriptor), data memory. This will benefit a convenient use of USB.