• Title/Summary/Keyword: patch loading

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A Study on the Design of Dual-Band Equilateral-Triangular Microstrip Antennas (듀얼-밴드 정삼각형 마이크로스트립 안테나 설계에 관한 연구)

  • 문정군;임정섭;장재삼;윤서용;황호순;이문수
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2003.05a
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    • pp.546-550
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    • 2003
  • For dual-band operation, it can be done by loading two pair of narrow slots in the equilateral-triangular patch, one embedded close to the side edges of the patch and the other inserted at the bottom edge of the patch. The obtained two operating frequencies are of same polarization planes. The frequency ratio of the two operating frequencies is turnabled by varing the positions and lengths of the inserted slots at the bottom edge of the patch. In this paper, A single-feed equilateral-triangular microstrip patch with two pairs of narrow slot for dual-frequency operation is printed on the substrate(TMN-4 Rosers Co.) of the 60 miles. the antenna radiation characteristics are calculated by Ensemble ver. 5.0 software, and compared with the experimental results.

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Formulation and Pharmaceutical Properties of Transdermal Patch of Flurbiprofen (플루비프로펜 함유 경피 패취제의 제제설계 및 약제학적 성질)

  • 이계주;고유현;우종수;황성주
    • YAKHAK HOEJI
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    • v.43 no.4
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    • pp.447-457
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    • 1999
  • The purpose of this study is to prepare the adhesive type patch containing flurbiprofen, and to demonstrate the feasibility of flurbiprofen administration through the intact skin using adhesive type patch preparation. For this purpose, two pressure sensitive adhesives, Polyisobutylene(PIB) and $Gelva^{\circledR}737$, were selected from the chemical grade of polymers, and the adhesive type patches of flurbiprofen were prepared. The release rate of flurbiprofen from the PIB-based adhesive patch was higher than that from $Gelva^{\circledR}737$ based adhesive patch. The release rate of flurbiprofen from the PIB-based A-type patch with 1.0mm, 1.5mm or 2.0mm thicknesses followed the first order kinetics. In the skin permeation study, using male hairless mouse skin, a monophasic skin permeation profile was observed with 1% flurbiprofen loading dose. The inclusion of palmitic acid or SLS(0.25~0.5%) as an enhancer produced a remarkable enhancement in the skin permeation rate of flurbiprofen, and the percentile ratio of drug and enhancer appeared to be important for the effective enhancement. In the in vivo percutaneous absorption study, the plasma concentration of the optimal formulation was significantly (p<0.01) higher than that of the conventional cataplasma ($Bifen^{\circledR}$). These studies demonstrate a good feasibility of flurbiprofen administration through the intact skin using a transdermal patch, and show a possibility of the development of flurbiprofen patches.

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Post-buckling Behaviour of Aluminium Alloys Rectangular Plate Considering the Initial Deflection Effect (초기 처짐 영향을 고려한 알루미늄 합금 사각형 판의 좌굴 후 거동)

  • Oh, Young-Cheol;Kang, Byoung-Mo;Ko, Jae-Yong
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.20 no.6
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    • pp.738-745
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    • 2014
  • In this paper, It is performing to the elastic and elasto-plastic large deformation series analysis using a numerical method for the initial deflection effect of the aluminum alloy rectangular plate in the elasto-plastic loading area patch loading size. It is assumed a boundary condition to be a simply supported condition and consider the initial deflection amplitude, aspect ratio. It examined the critical elastic buckling load and post-buckling behaviour of aluminium alloy A6082-T6 rectangular plate. It used a commercial program for the elastic and elasto-plastic deformation series analysis. If the initial deflection amplitude is smaller, the in-plane rigidity with increasing to load is reduced from the start and occurs significantly more increasing the amplitude. More higher the aspect ratio, the initial yield strength is gradually decreased, and the plate thickness thicker and occurs larger than the thin walled plate a reduction ratio of the initial yield strength of the patch loading size as 0.5.

Numerical analysis of interface crack problem in composite plates jointed with composite patch

  • Cetisli, Fatih;Kaman, Mete O.
    • Steel and Composite Structures
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    • v.16 no.2
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    • pp.203-220
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    • 2014
  • Stress intensity factors are numerically investigated for interfacial edge crack between two dissimilar composite plates jointed with single side composite patch. Variation of stress intensity factor under Mode I loading condition is examined for different material models and fiber orientation angles of composite plates and patch. ANSYS 12.1 finite element analysis software is used to obtain displacements of crack surfaces in the numerical solution and repaired plates are modeled in three dimensions. Obtained results are presented in the form of graphs. It is found that fiber orientation angle of composites is an effective parameter on interfacial stress intensity factor.

Numerical study of bonded composite patch repair in damaged laminate composites

  • Azzeddine, Nacira;Benkheira, Ameur;Fekih, Sidi Mohamed;Belhouari, Mohamed
    • Advances in aircraft and spacecraft science
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    • v.7 no.2
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    • pp.151-168
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    • 2020
  • The present study deals with the repair of composite structures by bonding composite patches. The composite structure is a carbon/epoxy laminate with stacking sequence [45/-45/0/90]S. The damaged zone is simulated by a central crack and repaired by bonding symmetrical composite patches. The repair is carried out using composite patches laminated from the same elemental folds as those of the cracked specimen. Three-dimensional finite element method is used to determine the energy release rate along the front of repaired crack. The effects of the repair technique used single or double patch, the stacking sequence of the cracked composite patch and the adhesive properties were highlighted on the variations of the fracture energy in mode I and mixed mode I + II loading.

Effect of Loading Split-Ring Resonators in a Microstrip Antenna Ground Plane

  • Lee, Hong-Min
    • Journal of electromagnetic engineering and science
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    • v.15 no.2
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    • pp.120-122
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    • 2015
  • This study presents a new, simple method for improving the front-to-back (F/B) ratio of a microstrip patch antenna (MSA) based on surface wave suppression. The back radiation of the MSA is significantly reduced by using the meandered ground plane edges and placing split-ring resonators (SRRs) in the middle of the meandered slots. By loading SRRs near the center of the meandered ground plane edges, some parts of the diffracted back-lobe power density can be reduced further. Compared to the F/B ratio of a conventional MSA with a full ground plane of the same size, an improved F/B ratio of 18 dB has been achieved experimentally for our proposed MSA.

Strategies of Caffeine Loading into Silk Fibroin Film for Weight Loss Patch

  • Yun, Na Kyong;Lee, Ki Hoon
    • International Journal of Industrial Entomology and Biomaterials
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    • v.27 no.2
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    • pp.312-316
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    • 2013
  • Caffeine is a thermogenic agent that can be used in weight loss products. In order to achieve a sustained release of caffeine, silk fibroin (SF) film was uses as carrier. It has been shown that the loading method of caffeine into SF film affected the uniform distribution of caffeine in the SF film. When caffeine was added directly into SF solution, gelation has been occurred immediately and prevented the uniform distribution of caffeine. On the other hand, caffeine was dissolved in methanol in order to load the caffeine in SF film and crystallize the SF film at the same time. However, due to the fast evaporation of methanol, caffeine was recrystallized on the surface of SF film rather than penetrating into the film. Finally, caffeine was loaded into pre-crystallized SF film and uniform distribution of caffeine could be achieved. There was an initial burst of caffeine during the first 15 min, but after that a sustained release was achieved.

A Switchable Microstrip Patch Antenna for Dual Frequency Operation

  • Sung, Young-Je
    • ETRI Journal
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    • v.30 no.4
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    • pp.603-605
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    • 2008
  • A novel design for equilateral-triangular microstrip antennas with switchable resonant frequency is proposed. For dual-frequency operation, the proposed design is achieved by loading a pair of slits in the triangular patch, and two PIN diodes are utilized to switch the slits on or off. By increasing the length of the slits, the lower resonant frequency can be varied in the range from 1.22 GHz to 1.72 GHz whereas the upper resonant frequency remains unchanged.

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Skin Permeation Characteristics of Estradiol Patches and Their Comparative Efficacy Test in Ovariectomized Rabbits (에스트라디올 패취의 피부투과 특성 및 난소제거 토끼에서의 비교 효력시험)

  • Ryoo, Je-Phil;Choi, Mi-Suk;Choi, Jong-Kun;Kim, Soo-Hyeon;Kim, Eung-Goo;Yoon, Byung-Il
    • Journal of Pharmaceutical Investigation
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    • v.25 no.1
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    • pp.47-54
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    • 1995
  • Transdermal patch formulations of estradiol to treat post-menopausal symptoms and prevent osteoporosis in women were developed and evaluated for the permeation characteristics through the excised hairless mouse abdorminal skin and the uterotropic effect on the ovariectomized rabbits. The design of patch formulations was optimized by varying several formulation parameters, such as type of enhancers, amount of enhancers, amount of drug loading and coating thickness. Compared to a commercially available transdermal product, several patch formulations showed the similar skin permeation profiles (following zero-order kinetics), but their skin permeation rates were lasted for the longer period (a week). In one-week uterotropic efficacy test in the ovariectimized rabbits, the selected patch formulations showed the positive effect in atrophy of the urogenital epithelium. The mean values of uterus weight in rabbits after application of patches containing estradiol were much higher than those in control group (containing no drug).

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The failure analysis of patch bonded repair on Al 6061-T6 alloy structures with cracked bolt hole (볼트 균열 홀을 갖는 알루미늄 6061-T6 합금의 패치 본딩 보수/보강 부위에 대한 파괴역학적 해석에 관한 연구)

  • Yoon, Young-Ki;Kim, Guk-Gi;Park, Jong-Jun;Yoon, Hi-Seak
    • Proceedings of the KSME Conference
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    • 2000.04a
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    • pp.148-152
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    • 2000
  • The aluminum alloy 6061-T6 has been successfully used in structural applications especially the pressure vessel of the Advanced Neutron Source research reactor. And aluminum alloys, including 6061-T6, have a face-centered-cubic crystals structure. Under normal circumstances face-centered-cubic crystal structures do not exhibit cleavage fractures even at very lo9w temperatures. In aluminum-based structures, plates frequently find use as connecting links. Mechanical fasteners are often utilized in instances where ease of application, familiarity with fabrication processes, and severe dynamic loading are of concern. Plates frequently find use as connecting elements in structures built from aluminum alloys. Many structural elements employ mechanical fasteners. Twenty and twenty aluminum alloy 6061-T6 plates, representing four different bolt patterns, were mechanically deformed. And variable materials such as A1 6061-T6, Al 2024-T3, Carbon/Epoxy, Glass/Epoxy Composite and Woven fiber composite, are used as patch materials. From this experiment, it has been shown that the strength of patch-repaired specimens is different with the patch materials.

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