• 전기학회논문지
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• 제63권12호
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• pp.1655-1660
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• 2014

In this paper, we propose a design of a triple-band microstrip circular patch antenna. The proposed antenna generates the triple frequency resonance at 1.85GHz(LTE), 2.45GHz(ISM) and 5.5GHz(WLAN). Firstly, we design the dual-band antenna. The dual-band antenna consist of the circular patch, slits, and the slot. The circular patch and slot are designed for dual frequency of 2.45GHz and 5.5GHz, respectively. And then the dual-band antenna is combined with additional arm-shaped structure for the triple-band characteristic. The arm-shaped structure is operated as the dipole. It is designed for lowest frequency of 1.85GHz. Each part of the antenna unites to a new structure. In order to design the proposed antenna automatically and optimally, APSO algorithm is adopted. During APSO, the mismatch of the proposed antenna is resolved. The optimal designed antenna has an acceptable return loss(-10dB) at each bands(i.e, 1.85GHz, 2.45GHz and 5.5GHz).

• 복식
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• 제58권5호
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• pp.118-133
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• 2008

The basic costumes of the joseon dynasty such as pants and jackets were not particularly distinctive over the period in comparison to po. The coat that was worn over pants and jacket, however, had different forms in the course of the joseon dynasty. In this paper, I will analyze the changing style of pyeonbokpo, the daily costumes of Joseon man, which were excavated in recent years. Changes in the collar style were the most distinctive of joseon pyeonbokpo such as cheolik, dapho, aekjueum, jikryeong, daechangyeui, jungchimak, and juyeui. Although pyeonbokpo had double collars in the early joseon dynasty, they disappeared in the seventeenth century: a straight line also replaced by a curve for the collar perimeter. Front-adjusting of pyeonbokpo was very deep in the early joseon dynasty; front-adjusting became simple in the late joseon dynasty, resulting in the central positioning of a ribbon. The rectangular form of a gusset(mu) was stitched to the bodice through various pleats. Gusset patterns changed greatly into various forms in the seventeenth and eighteenth centuries, along with the ladder gusset form. The long vest(dapho) was half-sleeved and had a deep front adjustment in the early joseon dynasty; however, it did not have collars and sleeves since the eighteenth century. The waist line of cheolik had the ratio of 1.2 to 1 for the bodice to skirt. But the length of skirts grew gradually into the ratios of 1 to 1, 1 to 2, and 1 to 3.8 while the waist line moved upwards to the chest line. Sleeves of all po had a straight form but they gradually developed the tendency to widen towards the wrists. Later, sleeves changed again, having a wide rectangular form starting from the armpits. Cheolik was widely worn in the early joseon dynasty; however, it was worn less in later years. Instead, clothes that had slits such as dopo, daechangeui, and jungchimak were greatly available. These characteristics of the change in men's costumes enable us to measure the time period of excavated findings despite the lack of records for Joseon graves.

• 한국항해항만학회지
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• 제28권1호
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• pp.43-49
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• 2004

결함검사는 생산공정에 있어서 상품의 디자인과 함께 매우 중요한 부분으로서, 상품의 경쟁력을 높이는데 필수 불가결한 것이다. 만약, 실시간 결함검출이 상품에 대한 어떤 손상도 없이 할 수 있다면, 품질 및 공정의 효율적 관리와 고비용 인력의 절감을 통하여 생산원가를 줄일 수 있다. 본 논문에서는 철판과 같은 표면에 결함이 있는 경우 필요한 정보만을 추출할 수 있는 3가지 공간필터법에 대하여 제안하였고, 공간필터의 특성을 통하여 결함검출 시스템을 구성하였다. 그리고, 최적의 표면결함 계측용 공간필터법을 개발하기 위하여 결함의 크기와 형태, 광도의 크기 및 외부 광간섭 그리고 슬리트의 개수와 같은 파라메타의 변화에 따른 측정 성능을 비교 및 분석하였다.

• Journal of Electrical Engineering and Technology
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• 제9권1호
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• pp.301-306
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• 2014

We proposed a new PCB-type 'common-mode current($I_c$) and differential-mode current($I_d$) detector' working for fast detection of $I_c$ and $I_d$ from the differential-mode signaling, with miniaturization effect and possibility of cheaper fabrication. In order to realize this device, we suggest a branch-line-coupler balun having a composite right- and left-handed(CRLH) one-layer microstrip phase-shifting line as compact as roughly ${\lambda}_g/14$. The presented balun obviously is different from the conventional bent-&-folded delay lines or slits on the ground for coupling the lines on the top and bottom dielectrics. As we connect the suggested balun output ports of the differential-mode signal lines via the through-port named U and coupled-port named L, $I_c$ and $I_d$ will appear at port ${\Delta}$ and port ${\Sigma}$ of the present device, in order. The validity of the design scheme is verified by the circuit-and numerical electromagnetic analyses, and the dispersion curve proving the metamaterial characteristics of the geometry. Besides, the examples of the $I_c$ and $I_d$ indicator are observed as the even and odd modes in differential-mode signal feeding. Also, the proposed device is shown to be very compact, compared with the conventional structure.

• 한국해안·해양공학회논문집
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• 제27권5호
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• pp.295-303
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• 2015

관성항과 비선형 항력항을 포함한 직립 슬릿벽에 의한 파의 산란을 고유함수전개법을 사용하여 해석하였다. 슬릿벽에서의 에너지 손실효과를 나타내는 비선형 항력항을 등가 선형화기법으로 선형화시켰다. Yoon et al.(2006)과 Huang(2007)이 제안한 실험식을 통하여 구한 항력계수를 적용한 해석결과는 Kwon et al.(2014)과 Zhu and Chwang(2001)의 수리모형 실험결과와 비교하였고, 서로 잘 일치함을 확인하였다. 개발된 해석모델을 이용하여 슬릿벽의 주요 설계변수들인 공극률, 잠긴 깊이, 슬릿 형상, 파랑특성 등을 바꿔가면서 슬릿벽에서의 에너지 손실효과를 평가하였다. 잠긴 깊이에 따라 다소 차이는 있지만 공극률이 0.1보다 작은 값에서 슬릿벽에서의 에너지 손실률이 가장 크게 일어났다. 현재의 해석해는 슬릿벽 방파제에 의한 소파효율을 예측하는데 유용하게 이용될 것이다.

• 한국의류학회지
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• 제16권4호
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• pp.485-493
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• 1992

Three kinds of tight skirts, slim type, straight type, and semi-tight type were investigated to obtain necessary information about the size of the back slit. Fourteen college students put on these experimental clothes and walked on the flat floor, going up and down the stairs. The dimensions of the back slit were measured by width and length. The stride length was taken from the record of footprints of walking. The correlation between the body measurement, stride length and the size of the back slit was studied. As a result of this experiment, the findings are as follows: 1. The size of the back slits differed from each skirt type at the level of p<0.001. In the case of walking on the floor, the average dimension of the back slit was 14.0 cm long 5.0 cm wide for the slim type,9.5 cm long 2.8 cm wide for the straight type and 2.1 cm long 0.5 cm wide for the semi-tight type. 2. In the case of walking on the stairways, the average dimension of the back slit was 16.0 cm long 5.8 cm wide for the slim type, 12.4 cm long 3.9 cm wide for the straight type and 3.1 cm long 1.1 cm wide for the semi-tight type. 3. The correlation between the height (stature, waist height, knee height) and the size of back slit was 0.3 to 0.6. The correlation between the girth (waist, hip) and the size of back slit was 0.3 to -0.5. 4. The correlation between the stride length and the size of back slit was 0.76 for the slim skirt, 0.56 for the straight skirt, 0.28 for the semitight skirt.

• 한국의류학회지
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• 제34권5호
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• pp.819-830
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• 2010

This study proposes medical gowns for interns and residents that address the functions of utility and activity. Based on the questionnaires, the prototype focused on the pockets for practical use and movement adaptability. Functional pockets were made by increasing pocket sizes and separating pockets with sections according to use. An inside pocket and a loop for an identification tag was placed on the chest pocket and the side seam pocket were oblique lined. To resolve horizontal stress on the back of the gown,6 cm action pleats were added at both ends of the bladebone. The elbow area was tucked up to improve the workplace activities. To reduce hamper on the gown hemline, slits were added along the gown side seam. The front button was changed into an inside button closure. The cuffs, belt, and back waist belt were removed due to occupational cases of inconvenience. The length of the sleeves was adjusted with belts to improve the movement of the arms. In accordance with design preference, the gown was designed to be knee-length with wrist length sleeves. Blue colored (2.5PB 3/12: by Munsell) material was inserted to reduce the contamination on the neck, cuffs, front closure, and hemline area. The planning cloth of the experimental gown was designed to improve activity function, cleaning, and comfort from light materials. The field test (with 30 doctors at university hospitals and the objective assessment with 9 subject groups)were done by the valuation between the existing gown and the prototype. The results showed that the prototype had to be modified by decreasing the pocket size, expanding the usage of the penholder, and simplify front pockets in order to maintain unity. The loop for the identification tag, inside pocket, and the blue colored material had to be removed. The front closure of the gown had to return to its original state.

• 비파괴검사학회지
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• 제24권6호
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• pp.597-602
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• 2004

유도초음파의 현장적응에 있어 전파모드를 규명하는 것은 매우 어렵지만 중요한 과제이다. 본 연구에서는 분산성이 적은 단일모드를 발생시키고 검출할 수 있는 기법에 대해 다루고 있으며, 현장 적용성과 자동화를 위해 비접촉식의 기법을 적용하였다. 모드 선택성을 강화한 비접촉식의 유도초음파 기법으로는 선배열 슬릿을 이용한 레이저빔을 이용하였으며, 에어커플 변환기를 수신자로 사용하였다. 선배열의 레이저 조명은 파장과 일치하여 특정한 모드를 발생시킬 수 있다 또한, 에어커플 변환기는 공기 중으로 누설되는 유도초음파를 수신각도를 조절하여 선택적으로 모드를 수신할 수 있다. 1mm 두께의 알루미늄 판에 덕 기법을 적용한 실험결과로부터 제안하는 기법의 유용성을 검증하였고, 특히 단일한 $a_0$모드의 발생 및 수신에 효과적인 기법으로 나타났다.

• 물과 미래
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• 제24권2호
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• pp.71-79
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• 1991

한 시험하천에서 평균유속, 수면경사, 통수단면, 수온 등 수리량과 부유사 농도, 부유사 및 하상도의 입경분포 등 유사량을 측정하였다. 측정 대상하천은 남한강의 제1지류인 청미천으로, 경기도 한평교 지점과 장호원의 원부교 지점을 택하였다. 청미천은 그 하상이 완전히 모래로 구성된 하천으로 전형적인 충적하천으로 간주된다. 본 연구에서 측정된 자료의 주요 분석결과는 다음과 같다: 1)시험하천의 경우, 홍수시에만 실질적인 유사이동이 있다; 2)수위-유량관계는 특히 저수시에 자주 변한다; 3)유량의 증가에 따라 하천의 마찰 역시 증가한다; 4) 평수나 저수시에는 부유사중에 이토나 점토가 지배적이나, 홍수시에는 모래가 지배적이다; 5) 유속및 부유사 농도의 연직분포는 각각 Prandt1-von Karman의 대수분포식과 Rouse의 지수분포식으로 표시될 수 있다. 이상의 결과들은 청미천에서의 측정결과에 의한 것이나, 이는 청미천에 국한되지 않고 하상이 모래로 구성된 충적하천의 경우 일반적으로 적용될 것으로 유추된다.

• 한국의류학회지
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• 제30권1호
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• pp.94-105
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• 2006

This study is focused on the man's costumes of Sadangpae(the troupe of performers) shown in Gamrotaenghwa (감로탱화) during the late Chosun dynasty. Originally Gamrotaenghwa was used as a painting for a Buddhist praying ceremony, 또Young-ga-cheon-do-je(영가천도제). It shows us the lives of the commoners in those days. Gamrotaenghwa reflects the changes of costume style in the late Chosun period. The early styles of po(포, coat) for male performers in the 17th century were changeui(창의) and dopo(도포), which had the front panels(seop) overlapped deeply and sleeves that got wider as time passed. After the 18th century, Male performers wore a simpler coat such as sochangeui(소창의), which had narrow sleeves and long slits on the both sides. Especially the coats of acrobats were fastened on the center front with buttons. Heuklip(흑립: black hat), somoja(소모자: small cap) and jeonlip(전립: wool hat) were used as hats for the male performers. Originally, heuklip was the hat that represented the noble status: yangban(양반). However, it was popularized among the commoners in the late Chosun period. As time passed on, the heuklip became more popular and its shape also changed. Somoja and jeonlip were shown throughout the entire Gamrotaenghwa. Unlike heuklip, those were common hats for Sadangpae. The costumes of entertainers shown in Gamrotaenghwa were very similar to those of the commoners. However, it seems that there were some differences of the costumes depending on the roles they performed.