• Journal of radiological science and technology
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• v.26 no.2
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• pp.49-56
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• 2003

The purposes of this study are to improve the ultrasound resolution of various nylon and metallic mono-filament wires, therefore, it was tested that it analyze on nylon mono-filament wire of 0.1 mm in A Co.'s ultrasonic phantom and synthesis of C15 g tissue mimicking materials(TMM), analyze resolution of nylon and metallic mono-filament wires in water and TMM. The results obtained were summarized as follows: 1. Metallic mono-filament wire of 0.1 mm and nylon mono-filament wire of 0.12 mm, 180 denier showed that it cleared dot echo pattern. 2. Metallic and nylon mono-filament wire of 0.2 mm showed that it cleared comet tail echo by reverberation artifact. 3. Nylon and metallic mono-filament wire of 0.1 mm showed that it can used for dead zone and axial resolution test. 4. Nylon mono-filament wire compared with metallic mono-filament wire showed that it satisfy elasticity and construction. 5. Degree of hardness of na not changed mono-filament's echo textures.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.10
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• pp.867-875
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• 2018

Conventional nylon wire cutting-type holding and release mechanisms (HRMs) are limited to securely hold the solar panel under launch environment as the size of the panel increases because the nylon wire is tightened directly on the surface of the solar panel. In this study, we proposed a nylon wire cutting-type HRM for 6U CubeSat's solar panel applying elliptic-shaped bracket with a Ball & Socket interface. The proposed HRM has the advantage of higher holding capability along in-plane and out-of plane directions of solar panel and simplicity in tightening process of nylon wire. The design drivers of structural design of CubeSat's solar panel with the proposed HRM were defined by structural analysis under launch loads. In addition, The design effectiveness of the proposed HRM was verified through the functional tests according to the thickness of nylon wire and the number of wire winding under various temperature conditions.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.5
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• pp.1235-1244
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• 1994

In this study, experimental results of the nucleate boling of wire-wrapped tubes are provided. Both water and R-113 were boiled. Solid stainless steel wires, stranded copper wires and stranded nylon wires were tested. Solid stainless wire is effective to enhance the boiling of water. The performance is approximately the same(or slightly better at certain conditions) as that of GEWA-T tubes. For the test range of wire diameter 0.6 $mm{\le}d{\le}2.6 mm$, the optimum gap width increases as the wire diameter increases. The maximum heat transfer coefficient was obtained for the 1.0 mm diameter wire, and it is 1.6 times larger than that of the GEWA-T at the heat flux of 20 $kW/m^{2}.$ Solid stainless wire is also effective to enhance the boling of R-113 at low heat fluxes. The performance of the wire-wrapped tube approaches that of GEWA-T. At high heat fluxes, however, the enhancement decreases. The reason may be attributed to the cavity shape and the high wettability of the refrigerants. Stranded copper or nylon wire is effective to enhance the boiling of R-113. The performance is approximately the same(or slightly better) as that of GEWA-T tubes. Maximum heat transfer was obtained for the stranded nylon wire, and it is approximately 1.4 times larger than that for the GEWA-T at the heat flux of 20 $kW/m^{2}.$ The reason may be atrributed to the favorable thermal environment in the restricted regions formed by twisted wires.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.21 no.5
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• pp.1-8
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• 2022

Fused deposition modeling (FDM), based on stacking a continuous filament of polymer or composite materials, is well matured and is thus widely used in additive manufacturing technology. To advance FDM-based 3D printing technology, the mechanical properties of additively manufactured composite materials must be improved. In this study, we proposed a novel FDM 3D printing process using metal wire-polymer composites, enabling enhanced mechanical properties. In addition, we developed a new type FDM filament of copper wire wrapped in nylon material for stable 3D printing without thermal damage during the printing process. After FDM printing of the copper wire-nylon composite filament, we conducted a tensile test to investigate the mechanical behavior of the printed composite materials. The experimental results confirmed that the tensile strength of the 3D-printed metal wire-polymer composites was higher than that of the conventional single polymer material. Thus, we expect that the FDM printing process developed in this study may be promising for high-load-bearing applications.

• Journal of Aerospace System Engineering
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• v.15 no.4
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• pp.1-6
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• 2021

The non-explosive holding and release mechanism is used to prevent damage to the mission component caused by explosives when the deployment structure for Cube Satellites is separated. However, among the several types available, the non-explosive holding and release mechanism system using nylon wires depend on the nylon wire knot method and tightening power of the worker. Therefore, in this study, we conducted experiments with the operation of a new holding and release mechanism system by conceptualizing the Boa System Dial, which can provide a constant tightening force regardless of worker proficiency and deploying a imitational solar panel. In this study, the process of binding and unbinding with constant tension was recorded while applying the novel non-explosive holding and release mechanism using the Boa System Dial proposed. In addition, required advances are indicated for the application of the proposed system to actual Cube Satellites.

• Journal of Biosystems Engineering
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• v.28 no.3
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• pp.209-216
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• 2003

Red pepper calyx cutting devices using a impacting force by a rotational cutter were devised and tested to obtain the fundamental data for development of a calyx removal unit. Fresh red peppers with 80∼87%(w.b.) of initial moisture contents were used as experimental materials. Square and wire type of rotational cutters were used to cut the red pepper calyx and the fresh red peppers were fed into the device both manually and automatically. Three rotational speeds of 250, 500, 700rpm were selected for a square, and 1000, 1500, 1800rpm for a wire type cutter respectively. Four types of red pepper fixing unit were used in manual feeding. The cutting rate of the square type cutter was over 50% regardless the shape and specification of the cutter. For the wire type cutter, the copper wire and nylon chord could not be applied to cut the red pepper calyx because of the low cutting rate. But for the fine wire, the cutting rate was higher and the cutting mechanism was more steady than copper wire and nylon chord. The cutting rate of automatic feeding and wire type cutting unit was about 70% for all levels of the rotational speed. The cutting rate was highly related to the impacting point of red pepper in carrier box. To increase the cutting rate using the rotational cutter, a proper device and mechanism was required to keep the impacting point consistently.

• The tire
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• s.22
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• pp.17-24
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• 1969

• Journal of Aerospace System Engineering
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• v.15 no.5
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• pp.81-88
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• 2021

In general, a non-explosive nylon wire cutting-based holding and release mechanism has been used to store and deploy deployable solar panels of CubeSat. However, with this method, accessing the solar panel's access port for charging the cube satellite's battery and electrical inspection and testing of the PCB and payloads while the solar panel is in storage is difficult. Additionally, the mechanism must have a reliable release function in an in-orbit environment, and reusability for stow and deploy of the solar panel, which is a hassle for the operator and difficult to maintain a consistent nylon wire fastening process. In this study, we proposed a pin-puller-based solar panel holding and release mechanism that can easily deploy a solar panel without cutting nylon wires by separating constraining pins. The proposed mechanism's release function and performance were verified through a solar panel deployment test and a maximum separation load measurement test. Through this, we also verified the design feasibility and effectiveness of the pin-puller-based separation device.

• Journal of Trauma and Injury
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• v.20 no.2
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• pp.72-76
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• 2007

Purpose: The purpose of this clinical trial was to evaluate the fixation method for treating alveolar fractures in an emergency department. Methods: The efficiency of using the fixation method was judged on the basis of clinical criteria. Stability, occlusion state, bleeding amount after fixation, operation time, and difficulties during procedural operation were recorded. Results: Eight patients were enrolled in this study. In all instances, the fixation method was effective in bleeding control. Each patient had a noticeable decrement in bleeding. A wire was used for four of the eight patients, and nylon strings was used for the others. The average operation time was 6.3 minutes for the wire patients and 2.8 minutes for the Nylon string patients. No specific problem was identified during the procedural operation. However, the difference in the fixation material influenced the effectiveness of the procedure, the operation time, and the satisfaction of the doctor. Conclusion: In the emergency department, the fixation method using wire or nylon string in the treatment of alveolar fractures is effective in bleeding control

• Journal of Aerospace System Engineering
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• v.12 no.5
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• pp.69-75
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• 2018

In this study, we proposed a nylon wire cutting-type solar panel separation mechanism for CubeSat applications using spring-loaded pogo-pins, which has been widely used as temporary electrical interface between two separate electronics. The mechanism proposed in this study has great advantages of higher holding capability, ability to constrain along in-plane and out-of-plane directions of solar panels, simplicity in tightening of nylon wire and synchronous separation of multiple panels. In addition, the pogo-pins used for the proposed mechanism act as electrical power interface, separation status switch and separation spring. In this study, the functionality of the proposed mechanism was validated through the separation tests with various number of nylon wire windings.