• 한국산학기술학회논문지
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• 제4권3호
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• pp.284-288
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• 2003

본 논문에서는 유궤도 이동로봇의 이점을 활용하고 궤도의 유연성을 높여주기 위해 금속 테잎형태의 유궤도를 갖는 이동로봇 시스템을 제작하였다 제작된 무인 운반용 이동로봇은 초음파 및 광(적외선)센서가 탑재된 센서부, 모터 및 엔코더로 이루어진 모터부. 사용자 인터페이스부, 중앙제어부, 컴퓨터 인터페이스부로 구성된다. 초음파센서를 이용하여 이동 경로상의 장애물을 감지하고, 광(적외선)센서를 이용하여 금속 테잎의 궤도를 정확히 감지하여 원하는 위치에 이동할 수 있도록 하였다 개발된 유궤도 이동로봇은 금속 테잎형태의 궤도를 사용함으로써 궤도의 유연성을 높여줄 백만 아니라 무인 이동로봇들의 하드웨어적 소프트웨어적인 비용을 상당부분 절감할 수 있도록 하였다.

• 한국음향학회지
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• 제11권2호
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• pp.28-37
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• 1992

본 연구에서는 압전 특성이 우수한 PZT계 압전세라믹스를 원판상으로 박판화하여 금속 진동판에 부착시킨 PZT/Metal음향변환기를 제작하였다. 이 때 압전 세라믹스를 박판화하기 위해 'tape casting 방법‘을 사용했으며, 제작된 PZT/Metal 음향 변환기를 압전 부자, 압전 스피커등의 소자에 응용 시키기 위해 음향특성을 연구하였다. 연구 결과, 세라믹스의 압전 계수($d_{31}$)이 증가함에 따라 레벨(dB)이 -6dB에서 - 14dB로 증가된다. 음향 변환기의 직경비 ${\eta}$가 0.7-08이고, 두꺼비 (${\beta}$)가 1일 때 최적 음압 특성을 나타냈으며, 음압은 -15~-16dB정도이었다.

• 전기학회논문지
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• 제66권1호
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• pp.243-248
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• 2017

This study used general carbon fibers(CF), which can be utilized for a low voltage cable screen, as well as metal-coated carbon fibers(MCF) to make cables and analyzed the properties of electromagnetic effectiveness. Both braid CF and MCF cables with 3,000 strands, 16 spindles, and braid density of 90% or over were adopted. The tape-type MCF specimens were spread into a tape(width: 15mm) using a hot melt to make a cable. The shield effectiveness was measured up to the 1GHz range in accordance with IEC 62153-4-6; braid shielded cables featured a superior shielding effect at 63dB than tape-type shielded cables. That was because the tape-type shielded cable has relatively more gaps and holes between carbon fibers than the braid type, resulting in a more inflow or emission of electromagnetic waves. In the case of braid cables, the characteristics of their electromagnetic waves were enhanced, with higher spindles and higher conductivity of carbon fibers. The shield effectiveness of the MCF shielded cable, however, was lower than that of tin-coated one.

• 한국전기전자재료학회논문지
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• 제13권3호
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• pp.247-253
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• 2000

We evaluated the electric properties of Bi-2223 jointed tapes processed by both resistive-and superconducting-joint methods. For resistive-joint. filler materials of wood metal Pb/Sn. In and silver paste were used whereas for superconductive-joint lap joint method was used. In the resistive joint tape. critical transport property(CCR) n-value and contact resistance were observed to be in the range of 10-85% 1-8,9. and 0.71x10$\^$-6/-0.13x10$\^$-6/Ω, respectively. depending on their filler materials. Specifically it is believed that the electrical properties of resistive joint tape are significantly related to the resistivity of filler materials. On the other hand the CCR of superconductin joint type was varied 55 to 85% with uniaxial pressure probably due to the irregular microstructure in the transition region.

• 한국초전도ㆍ저온공학회논문지
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• 제7권3호
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• pp.9-12
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• 2005

[ $Y_1Ba_2Cu_3O_{7-8}$ ] (YBCO) coated conductor has been fabricated by batch-type process using oxide-precursor-based metal-organic deposition (MOD) method. The batch-type process can be scaled up more simply to Produce long-length YBCO conductor than the reel-to-reel process. Also, it has less handling problems and is adequate to the ambient gas environment. In this work, YBCO oride powder was used as a starting precursor for MOD method. After reel-to-reel dip coating process, me ter-long-buffered metal tape was wound around a cylinder and underwent calcination and annealing processes. Annealed YBCO films showed good c-axis alignment and dense surface morphology with no cracks, but exhibited very low critical current density of $10^5\;A/cm^2$.

• 한국초전도ㆍ저온공학회논문지
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• 제22권3호
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• pp.13-19
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• 2020

This study presents the experiment and simulation results on the magnetic field response and electrical stability behaviors of no-insulation (NI) and metal insulation with stainless steel tape (MI-SS) which wound in form of racetrack type coils. First of all, the structural design of the racetrack type bobbin was shown along with its parameters. Then, the current-voltage tests were carried out to measure the critical current of both test coils. Also, the sudden discharging and charging tests were performed in the steady state to estimate the decay field time and magnetic field response, respectively. Finally, the overcurrent tests were conducted in the transient state to investigate the electrical stability of these test coils. Based on the experimental results, the contact surface resistances were calculated and applied to the field coils (FCs) of 10-MW-class second generation high temperature superconducting generator (2G HTSG) used in wind offshore environment. The charging delay time and electrical stability for NI and MI-SS HTS FCs of 10-MW-class 2G HTSG are analyzed by the equivalent circuit model and the key parameters which were obtained from the electromagnetic finite element analysis results.

• 한국초전도ㆍ저온공학회논문지
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• 제24권3호
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• pp.30-34
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• 2022

Effects of electron beam (EB) irradiation on the mechanical strength of Cu (conducting sheath) and Nb (diffusion barrier) of Cu/Nb/MgB₂ superconducting was investigated. Wire- and tape-type Cu/Nb/MgB₂ samples were irradiated at E-beam energy of 2.5 MeV and 5 mA and a maximum E-beam dose was 5×10¹⁷ e/m². The hardness value of Cu and Nb region was measured by the Vickers micro-hardness method. In the case of the wire sample, the hardness of Cu and Nb increased proportionally as the dose was increased up to 5×10¹⁷ e/m², whereas in the case of the tape sample, the hardness increased up to a dose of 0.5×10¹⁷ e/m², and decreased slightly 5×10¹⁷ e/m². The hardness increase of Cu and Nb is believed to be due to the decrease of the deformability of Cu and Nb due to the defects formed inside the materials by E-beam irradiation.

• 한국세라믹학회지
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• 제33권11호
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• pp.1267-1275
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• 1996

Green sheet was prepared by tape casting in the composition of (1-x)Pb(Mg1/3Nb2/3)O3-PbTiO3 system using Pb(Mg1/3Nb2/3)O3 and PbTiO3 synthesized with PbO, Nb2O5 MgO and TiO2 The densest green sheet was obtained in the weight ratio 70:30 of powder to binder. Green sheet wasmultilayered in metal mould and formed into lamination at 7$0^{\circ}C$, 300kg/cm2 The lamination was sintered at 110$0^{\circ}C$ 2hr, Dielectric constant and Curie temperature of disc type sintered body was highered with increasing the amount of PbTiO3 and was in the range of 19000-21000, -7~45$^{\circ}C$ respectively. Green and sintered relative density of lamination was 61% and 95% respectively.

• 대한금속재료학회지
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• 제56권11호
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• pp.835-843
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• 2018

In this work, we report a delta rosette strain sensor based on highly stretchable silver nanowire (AgNW) percolation piezoresistors. The proposed rosette strain sensors were easily prepared by a facile two-step fabrication route. First, three identical AgNW piezoresistive electrodes were patterned in a simple and precise manner on a donor film using a solution-processed drop-coating of the AgNWs in conjunction with a tape-type shadow mask. The patterned AgNW electrodes were then entirely transferred to an elastomeric substrate while embedding them in the polymer matrix. The fabricated stretchable AgNW piezoresistors could be operated at up to 20% strain without electrical or mechanical failure, showing a maximum gauge factor as high as 5.3, low hysteresis, and high linearity ($r^2{\approx}0.996$). Moreover, the sensor responses were also found to be highly stable and reversible even under repeated strain loading/unloading for up to 1000 cycles at a maximum tensile strain of 20%, mainly due to the mechanical stability of the AgNW/elastomer composites. In addition, both the magnitude and direction of the principal strain could be precisely characterized by configuring three identical AgNW piezoresistors in a delta rosette form, representing the potential for employing the devices as a multidimensional strain sensor in various practical applications.

• 한국의류산업학회지
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• 제20권2호
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• pp.219-225
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• 2018

The purpose of this study is to make an ideal dummy for adult Maltese with proper investigation of its character and direct measurement of dog body-shape. The results of the study are as follows; First, there were 6 factors to affect the characteristics of Maltese body in the analysis, which are size of body, leg shape, chest shape, leg thickness, body length, length between fore-legs. In the cluster analysis with the 6 factors there were two types of Maltese body. Type 1 has body characteristics with large body, thick leg, and small distance between front legs. Type 2 has average size of all factors including body size, leg thickness, and length between fore-legs. Second, type 2 was selected as a representative one to make a dummy reflected body shape of characteristics because it took 67.71% from entire considered factors and has average value in the measured size. The first dummy pattern was planned by copying the surface area of the representative body shape with the method of surgical tape. A dummy of single body with trunk and legs was made using 30's cotton cloth, polyester inside batting, compressed form PVC and metallic wire on the joint of trunk and legs to support dummy shape. The second pattern was made by correcting size difference of the pattern and adding the pattern of neck covering plate, metal magnetic button was inserted on the center of joint area of trunk and legs to make detachable legs for easy slip on and off the pet's wear.