• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.20 no.5
• /
• pp.874-879
• /
• 2016

A wideband stacked patch antenna with parasitic elements, rectangular and triangle shaped patches, is proposed. Two different shaped parasitic elements are placed in the above of main rectangular microstrip patch antenna in order to achieve wide bandwidth for 860 MHz band. Coupling between the main patch and parasitic patches is realized by thick air gap. The gap and locations of parasitic patches are found to be the main factor of the wideband impedance matching. The proposed antenna is designed and fabricated on a ground plane with small size of $119mm{\times}109mm$ for application of compact transceivers. The fabricated antenna on an FR4 substrate shows that the minimum measured return loss is below -11.68dB at 824 MHz and an impedance band of 818~919 MHz(11.7%) at 10dB return loss level. The measured radiation patterns are similar to those of a conventional patch antenna with maximum gain of 2.11 dBi at 824 MHz.

• The Korean Journal of Pain
• /
• v.31 no.1
• /
• pp.39-42
• /
• 2018

Background: Venipuncture pain is an uncomfortable suffering to the patient. It creates anxiety, fear and dissatisfaction. The ketoprofen transdermal patch is a proven treatment for musculoskeletal and arthritic pain. We planned this study to evaluate the efficacy of the ketoprofen patch to reduce venipuncture pain. Methods: Two hundred adult patients, aged 18-60 years, of either sex, ASA grade I or II, were enrolled. Presuming that therapy would decrease venipuncture pain by 30%, a power calculation with ${\alpha}=0.05$ and ${\beta}=0.80$ required enrollment of at least 24 patients into each group. However, 100 patients in each group were recruited. Group I (Control) received a placebo patch; Group II (Ketoprofen) received a 20 mg ketoprofen patch. A selected vein on the dorsum of the patient's non-dominant hand was cannulated with 18 g intravenous cannula 1 h after the application of the respective patch. Assessment of pain was done by a 10 cm visual analogue scale (VAS) of 0-10, where 0 depicts "no pain" and 10 is "the worst imaginable pain". The venipuncture site was assessed for the presence of skin erythema, swelling and rashes at 12 h, 24 h and at the time of decannulation. Results: Incidence of pain was 100% (94/94) in the control group as compared to 93% (85/91) in the ketoprofen group. The severity of the venipuncture pain was 6 (2) and 2 (2) for control and ketoprofen groups respectively (P < 0.05). Conclusions: Application of a ketoprofen patch at the proposed site of venipuncture one hour before the attempt is effective and safe for attenuating venipuncture pain.

• Journal of Pharmaceutical Investigation
• /
• v.36 no.2
• /
• pp.97-102
• /
• 2006

The aim of this study was to investigate the feasibility and optimize permeability of slim patch type as a transdermal delivery system of caffein. Slim patch type was formulated and tested in modified Franz diffusion cell across cellulose membrane and hairless mouse skin in pH 5.8 phosphate buffer solution (PBS). The effect of $Pharmsolv^{\circledR}$ and drug concentration on permeation at four model, 1,2% $Pharmsolv^{\circledR}$ with $0.12\;mg/cm^2$ caffein and 0.12, $1.2\;mg/cm^2$ caffein with 2% $Pharmsolv^{\circledR}$ through hairless mouse skin was studied in vitro. The release of caffein from slim patch with various loading was fitted by the Higuchi's diffusion equation. The result showed that chemical $Pharmsolv^{\circledR}$ produced a large and significant increase of permeation. The effect of 2% $Pharmsolv^{\circledR}$ on permeation of caffein was greater about 10-fold greater than 1% $Pharmsolv^{\circledR}$ in first 60 minutes. The effect of drug concentration, however, was lower than that produced by chemical $Pharmsolv^{\circledR}$. Within the tested system, the most efficient combination for caffein slim patch type was $0.12\;mg/cm^2$ caffein with 2% $Pharmsolv^{\circledR},$ although $1.2\;mg/cm^2$ caffein with 2% $Pharmsolv^{\circledR}$ showed highest amounts permeation, because permeated percentages were significantly lower about $1/4{\sim}1/5$ times.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.42 no.1
• /
• pp.67-78
• /
• 2005

We proposed a blind watermarking for 3D mesh model using the patch CEGIs. The CEGI is the 3D orientation histogram with complex weight whose magnitude is the mesh area and phase is the normal distance of the mesh from the designated origin. In the proposed algorithm we divide the 3D mesh model into the number of patch that determined adaptively to the shape of model and calculate the patch CEGIs. Some cells for embedding the watermark are selected according to the rank of their magnitudes in each of patches after calculating the respective magnitude distributions of CEGI for each patches of a mesh model. Each of the watermark bit is embedded into cells with the same rank in these patch CEGI. Based on the patch center point and the rank table as watermark key, watermark extraction and realignment process are performed without the original mesh. In the rotated model, we perform the realignment process using Euler angle before the watermark extracting. The results of experiment verify that the proposed algorithm is imperceptible and robust against geometrical attacks of cropping, affine transformation and vertex randomization as well as topological attacks of remeshing and mesh simplification.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.27 no.1
• /
• pp.48-57
• /
• 2007

The fatigue crack growth behavior of a cracked and patch-repaired Ah2024-T3 panel has been monitored by acoustic emission(AE). The overall crack growth rate was reduced The crack propagation into the adjacent hole was also retarded by introducing the patch repair. AE signals due to crack growth after the patch repair and those due to debonding of the plate-patch interface were discriminated by usiag the principal component analysis. The former showed high center frequency and low amplitude, whereas the latter showed long rise tine, low frequency and high amplitude. This type of AE signal recognition method could be effective for the prediction of fatigue crack growth behavior in the patch-repaired structures with the aid of AE source location.

• Journal of the Institute of Convergence Signal Processing
• /
• v.6 no.4
• /
• pp.198-205
• /
• 2005

In this paper, the miniaturization of aperture-coupled RHCP patch antenna for the GPS system is treated. Circularly polarization characteristics is implemented by truncating diagonal corners of the square patch. Antenna size is reduced by inserting four uniform slits at the patch edges, which was equivalently lengthened the surface current by meandering it, This antenna uses aperture-coupled feeding structure with crossed-slot shape in order to give easy miniaturization of RHCP patch antenna. Simulated and measured results show that $42.7\%$ lower antenna size is obtained, and also $56\%$ lower -10dB bandwidth and $38.5\%$ lower 3dB AR bandwidth are obtained. when the proposed design scheme is applied to a commercial GPS antenna structure, $42.9\%$ lower patch size and $56\%$ lower 3dB AR bandwidth compared to commercial antenna at the same frequency are obtained.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.15 no.10 s.89
• /
• pp.922-930
• /
• 2004

In this paper, the 3-dimensional microstrip antenna, where the lis is attached near the patch, on the pound and both patch and ground in zigzag, is designed and fabricated to miniaturize size of antenna. The path of surface current and permittivity in patch are increased because of attached Iris near the patch, on the pound and patch and found. In particula., the maximum size reduction effect among the three-type of $79.1\%$(17 mm$\times$90 mm) was presented in zigzag-type compared with the rectangular microstrip patch antenna(MPA) with a height of 9 mm at the resonant frequency of 1.575 GHz. The gain showed -1.15 dBd, -10 dB bandwidth showed 6.2$\%$(98 MHz), and HPBW of E-plane showed $154^{\circ}$. As that result we could confirm that the 3-dimensional structure with attached Irises is the proper form for the miniaturization of microstrip antenna.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.8 no.5
• /
• pp.56-67
• /
• 2005

Rapid and reckless economical development is causing nationwide deforestation; more and more forest is being developed to be used as a base for economic advancement. While benefiting the national economy, this destruction of forest is creating a serious problem in the National Land Plan. To solve this problem, it is imperative to understand the current condition of damaged forest and make an environment-friendly plan. This paper explains the principles of spatial plan and sets the criteria for the plan, such as patch size, connectivity, and edge of the Landscape Ecology. The paper assesses the conservational value of area that are currently being developed or planned to be developed to figure out the current environmental situation. This conservational value was verified by the field survey. The result of assessment appears that the patch size of the major mountains in site is over 1,000ha and edge is located widely beside roads. The area of the high connectivity is located agriculture area in valley or narrow roads. The research shows that the patch size is related to biodiversity the larger the patch size, the more populated the species are. The research also reveals the conservational value indicated by degree of connection to forest, difference in the structure of vegetation between core area and edge area, and effects of surrounding environment. In further study, we will assess other criteria of conservation value, such as patch shape and fragmentation to the Landscape Ecology, and apply those criteria in biological aspects of the spatial plan.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.14 no.3
• /
• pp.467-474
• /
• 2019

In this paper, we studied a method for a broadband stacked patch antenna structure which is widely used for bandwidth improvement. The characteristics according to the distance between the two patches were analyzed and the impedance matching was optimized by connecting parallel open stubs to the main patch feed line. The shunt matching stub is inserted underneath the parasitic patch and so it does not require additional space, which enables the proposed antenna structure to be advantageous in miniaturizing antenna. The effects of the various parameters on the antenna performance are examined, and we introduced the design procedure for the proposed antenna to operate in the frequency range of 2.3~2.7GHz. Experimental results show that the bandwidth of the proposed antenna is about 480MHz with 2.27~2.75GHz bandwidth. And the antenna gain was 5.8dBi at 2.3GHz and 7.8dBi at 2.6GHz within the bandwidth.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.17 no.6
• /
• pp.1063-1068
• /
• 2022

The modern society has become entry into the information age after the spread of Internet. In the information age, internet was developed from the wired access to the wireless Internet access. When a surge in demand for wireless Internet access, performance and speed of 2.4 and 5GHz band for Wi-Fi which leads to saturation of the communication was significantly fall. Accordingly, the communication of the 6GHz band for Wi-Fi 6E came to be interested. In this paper, we studied the design and fabrication of microstrip patch antenna to be used in wireless communication systems operating at around 6GHz band. To obtain antenna parameters such as patch size, inter patch space, antenna was simulated by HFSS(High Frequency Structure Simulator). From these parameters, slot microstrip patch antenna is fabricated using FR-4 of dielectric constant 4.4. The characteristics of fabricated patch type microstrip antenna were analyzed by network analyzer.