• 농업과학연구
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• 제40권2호
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• pp.139-146
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• 2013

This study was performed to develop a rapid test kit for pathogenic Staphylococcus in various samples. The rapid detection kit has been fabricated based on nitrocellulose lateral-flow strip. Colloidal gold and Staphylococcus antibodies were used as a tag and a receptor, respectively. Manually spotted Staphylococcus antibody and anti-mouse antibody on the surface of nitrocellulose membrane were used as test and control lines, respectively. Feasibility of the rapid kit to detect Staphylococcus aureus in samples were evaluated. The intensity of the color of the test line started to increase with the samples in which higher concentration of the cells were contained. The sensitivity of the sensor was $10^6$ cfu/mL Staphylococcus spiked in PBS. Also, the rapid test kit could detect $10^5$ cfu/mL of Staphylococcus in chicken meat extract.

• JSTS:Journal of Semiconductor Technology and Science
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• 제2권1호
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• pp.59-69
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• 2002

A semi-analytical model based on exact numerical analysis of the 2DEG channel in pseudo-morphic HEMT (PMHEMT) is presented. The exactness of the model stems from solving both Schrodinger's wave equation and Poisson's equation simultaneously and self-consistently. The analytical modeling of the device terminal characteristics in relation to the charge control model has allowed a best fit with the geometrical and structural parameters of the device. The numerically obtained data for the charge control of the channel are best fitted to analytical expressions which render the problem analytical. The obtained good agreement between experimental and modeled current/voltage characteristics and small signal parameters has confirmed the validity of the model over a wide range of biasing voltages. The model has been used to compare both the performance and characteristics of a PMHEMT with a competetive HEMT. The comparison between the two devices has been made in terms of 2DEG density, transfer characteristics, transconductance, gate capacitance and unity current gain cut-off frequency. The results show that PMHEMT outperforms the conventional HEMT in all considered parameters.

• 대한조선학회지
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• 제24권4호
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• pp.9-18
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• 1987

The hydrodynamic radiation forces acting on a ship travelling in waves have been conventionally treated by strip theories or by direct three dimensional approaches, most of which have been formulated in frequency domain. If the forward speed of a ship varies with time, or if its path is not a straight line, conventional frequency domain analysis can no more be used, and for these cases time domain analysis may be used. In this paper, formulations are made in time domain with applications to some problems the results of which are known in frequency domain. And the results of both domains are compared to show the characteristics and validity of time domain solutions. The radiation forces acting on a three dimensional body within the framework of a linear theory. If the linearity of entire system is assumed, radiation forces due to arbitrary ship motions can be expressed by the convolution integral of the arbitrary motion velocity and the so called impulse response function. Numerical calculations are done for some bodies of simple shapes and Series-60[$C_B=0.7$] ship model. For all cases, integral equation techniques with transient Green's function are used, and velocity or acceleration potentials are obtained as the solution of the integral equations. In liner systems, time domain solutions are related with frequency domain solutions by Fourier transform. Therefore time domain solutions are Fourier transformed by suitable relations and the results are compared with various frequency domain solutions, which show good agreements.

• 한국정밀공학회지
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• 제21권5호
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• pp.131-141
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• 2004

In this study a 3-D automatic die design supporting system for a bonnet panel has been developed using Pro/ROGRAM of the widespread CAD software Pro/ENGINEER A standard drawing die was defined in terms of the punch profile, the die face geometry, and the blank sheet size. The strip layout of a trimming die was defined, in addition, in terms of the trimming line and the locations of scrap cutters. Necessary relations for each design step are formulated and rules for bottom-up type 3-D die design were set up for the automatic design of drawing and trimming dies of a bonnet. With the input geometric data of punch profile, die face, and blank sheet, this 3-D design supporting system could complete the basic design process, in case of the bonnet drawing die, in a time 78% shorter than that required by a typical 2-D CAD system. The new design system showed remarkable design efficiency also when it was applied to the case of redesign and modification of the previous standard output for a different car type.

• 한국항행학회논문지
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• 제21권2호
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• pp.193-199
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• 2017

본 논문에서는 이중대역 저지 특성을 가지는 2.4 GHz WLAN (2.4 ~ 2.484 GHz) 및 UWB (3.1 ~ 10.6 GHz) 겸용 모노폴 안테나를 제안하였다. 3.5 GHz WiMAX 대역 저지 특성을 얻기 위하여 기존의 방사패치 중앙에 위치한 U-형태 슬롯을 대신하여 방사패치 가장자리에 위치하는 한쌍의 L-형 슬롯이 사용되고, 반면에 7.5 GHz 대역 저지를 위하여 급전선 인근에 배치되는 한 쌍의 C-형태의 스트립 공진기를 사용한다. 제안된 안테나의 제작 및 측정 결과, 임피던스 대역폭 (${\mid}S_{11}{\mid}{\leq}-10dB$) 이 8.62 GHz (2.38 ~ 11 GHz)로 2.4 GHz WLAN 대역을 포함한 UWB 대역을 충분히 만족하고, 반면에 3.5 GHz WiMAX 저지 대역 (${\mid}S_{11}{\mid}$ > -10 dB) 은 1.13GHz (3.15 ~ 4.28 GHz), 7.5 GHz 저지 대역은 800 MHz (7.2~8 GHz) 의 저지 대역폭을 가지는 것을 확인 할 수 있었다. 특히 사용하고자 하는 전 주파수 대역에서 안정되고 우수한 무지향성 방사패턴을 얻을 수 있었으며 2.51~6.81 dBi의 높은 이득 또한 얻을 수 있었다.

• 한국정보통신학회논문지
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• 제21권4호
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• pp.679-687
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• 2017

본 논문에서는 DGS (Defected Ground Structure)를 적용한 WLAN/WiMAX 시스템에 적용 가능한 모노폴 안테나를 제안하였다. 제안된 안테나는 마이크로스트립 급전을 바탕으로 두 개의 선로와 DGS를 갖도록 구성하여 삼중대역 특성을 갖도록 설계하였다. 두 개의 선로 그리고 세 개의 슬릿의 위치 및 길이와 DGS 위치와 길이를 적절한 조정하여 본 논문에서 요구되는 특성을 얻기 위한 최적화 수치를 얻었다. 제안된 안테나는 $34mm(W_1){\times}34mm(L_1){\times}1.6mm(t)$의 비유전율 4.4인 FR-4 유전체 기판 위에 $17.0mm(W_6){\times}30.75mm(L_3+L_4+L_9)$의 크기로 제작되었다. 제작 및 측정결과로부터 -10 dB 임피던스 대역폭을 기준으로 360 MHz (2.335~2.695 GHz), 645 MHz (3.37~4.015 GHz) 그리고 1,770 MHz (5.14~6.91 GHz)의 대역폭을 얻었다. 또한 제안된 안테나는 요구되는 삼중대역에서 측정된 이득과 방사패턴의 얻었다.

• 마이크로전자및패키징학회지
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• 제28권3호
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• pp.25-32
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• 2021

본 논문에서는 X-Band 대역에서 이중 편파 특성을 갖는 Magneto-Electric(ME) dipole 배열안테나를 제안하고, 이를 Low Temperature Co-fired Ceramic (LTCC) 공정을 이용하여 구현 및 측정하였다. 제안된 배열안테나는 LTCC로 구성된 1 × 1 ME dipole 안테나 32 개를 Teflon PCB에 배열하여 8 × 4 배열 안테나로 구성된다. 1 × 1 ME dipole 안테나는 두 쌍의 방사체에서 각각 수직 편파와 수평 편파를 방사하여 이중 편파를 구현하게 된다. 2개의 Port 급전은 LTCC를 이용한 적층 공정을 통해 구현하였으며, 각 각의 Port는 포트 간 격리도를 확보하기 위해 Γ-shaped feeding strip을 통해 독립적으로 방사체에 급전된다. 안테나 배열에 사용된 Teflon PCB는 4층 구조로 형성하였으며, 상단 면과 하단 면을 통해 2개의 Port가 급전된다. 그리고 배열되는 안테나와 Teflon PCB의 임피던스 정합을 위해 Teflon PCB의 전송선로에 λ_g/4 변환기를 적용하였으며 시뮬레이션을 통해 최적 파라미터를 얻었다. 구현된 ME dipole 8 × 4 배열안테나의 크기는 15.5 mm × 11 mm × 4.2 mm이며, Port 1 급전 시 측정된 방사 최대 이득은 18.2 dBi, cross-pol은 1.0 dBi이고 Port 2 급전 시 측정된 방사 최대 이득은 18.1 dBi, Cross-pol은 3.2 dBi로 확인하였다.

• 한국의류학회지
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• 제26권6호
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• pp.821-832
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• 2002

The purpose of this study was to develop grading method of the basic brassiere patterns therewith, provide for 12 size's brassiere patterns and prove fitness of their's and shape. The collected data were statistically processed using the SAS 6.12 for Means, Standard Deviation, etc. The results of this study can be summarized as follows; 1. The basic sizes adopted at the first design stage (see fig.1-2) were 75AA, 75A and 75B each of which was designed as upper foundation basic pattern in reference to the cup size. At the second stage, each of the upper body foundation basic pattern was used to design lower cup, upper up, front panel and wing in their order(see fig.3-6). At the third stage, the other sizes were graded in reference to the three brassiere patterns (75AA, 75A and 75B) to produce 12 brassiere sizes(see Tab. 7-8). In order to develop the basic patterns of adult women's brassieres, 33 women were selected per 11 size combination(3 women per size combination), and then, their brassiere fitting was teated. As a result, the fronts of the basic patterns were found to have such problems as undone front center, poor levelling of upper cup's bottom line or lower cup's top line, poor shape of upper cup's outside top line and shoulder strip position. On the other hand, on the rear side of the basic patterns, the central part of the wing was slightly lifted, while the wing width and straps'interval did not befit the ful1-cup brassiere. The result of this first brassiere fitting test showed that the functionality and aesthetics of the basic pattern brassieres were more or less satisfactory, and thus, the problems were addressed for the second teat. In the second test, the aesthetics, breast-shaping effect and functionality of the basic pattern brassieres were much improved. 2. We were to present the final brassiere sizing system to extend the interior length of breast and the exterior length of breast on the basis of fitting test. Thereby, 75B$.$80A$.$80B$.$85A$.$85B's the interior lengths of breast were enlarged to 0.7cm, the rest size was enlarged to 0.5cm and the exterior length of breast was enlarged to 0.5cm regardless of sizes. 3. The upper foundation basic patterns of 75AA and 75B were presented and and the basic brassiere pattern and grading pattern were presented through to.

• 대한전자공학회논문지SD
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• 제39권3호
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• pp.49-60
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• 2002

본 논문에서는 DRAM 모듈의 전원 평면에 대한 효과적인 설계 방법을 제시하였고 그 방법은 다음과 같이 세 단계로 구성되어 있다. 1) PEEC 등가회로를 이용한 2D 전송선 구조로 전원평면의 모델링 및 해석. 2) 측정값 비교를 통한 해석 결과 검증. 3) 전원 평면의 물리적 파라미터를 이용한 설계 가이드 제시. 제시한 내용을 바탕으로 하여 DRAM 모듈에서 전원 및 접지평면 성능을 안정화를 이루기 위한 효과적인 De-coupling 커패시터의 용량과 개수를 결정하는 방법을 기술하였다 이 설계 방법론은 스트립 구조 및 do-coupling 커패시터를 갖는 DRAM 모듈에서 효과적으로 사용할 수 있다.

• 한국정보통신학회논문지
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• 제22권2호
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• pp.338-346
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• 2018

본 논문에서는 W-LAN/WiMAX 시스템에 적용 가능한 모노폴 안테나를 설계 제작하였다. 제안된 안테나는 마이크로스트립 급전을 바탕으로 세 개의 선로와 하나의 슬릿을 갖도록 구성하여 삼중대역 특성을 갖도록 설계하였다. 세 개의 선로의 길이와 슬릿을 적절하게 조정하여 본 논문에서 요구되는 특성을 얻기 위한 최적화된 수치를 얻었다. 제안된 안테나는 $42.5mm(W1){\times}52mm(L1){\times}1.0mm(t)$의 유전체 기판 위에 $32.0mm(W2+W3){\times}47.1mm$ (L3+L4+L5+L8)의 크기로 제작되었다. 제작 및 측정 결과로부터 158 MHz (813 ~ 971MHz), 630 MHz (2.10 ~ 2.73GHz) 그리고 1190 MHz (4.83 ~ 6.02GHz)의 대역폭을 얻었다. 또한 제작된 안테나의 통해 삼중대역 안테나에서 요구되는 이득과 방사 패턴 특성을 확인하였다.