• Journal of electromagnetic engineering and science
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• 제9권2호
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• pp.85-97
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• 2009

As operating frequency is raised and as more integration with active and passive elements is required, it becomes difficult to fabricate more than 120 ${\Omega}$ characteristic impedance of a mierostrip line. To solve this problem, an equivalent high impedance transmission-line section is suggested, which consists mainly of a pair of coupled-line sections with two shorts. However, it becomes a transmission-line section only when its electrical length is fixed and its coupling power is more than half. To have transmission-line characteristics(perfect matching), independently of coupling power and electrical length, two identical open stubs are added and conventional design equations of evenand odd-mode impedances are modified, based on the fact that the modified design equations have the linear combinations of conventional ones. The high impedance transmission-line section is a passive component and therefore should be perfectly matched, at least at a design center frequency. For this, two different solutions are derived for the added open stub and two types of high impedance transmission-line sections with 160 ${\Omega}$ characteristic impedance are simulated as the electrical lengths of the coupled-line sections are varied. The simulation results show that the determination of the available bandwidth location depends on which solution is chosen. As an application, branch-line hybrids with very weak coupling power are investigated, depending on where an isolated port is located, and two types of branch-line hybrids are derived for each case. To verify the derived branch-line hybrids, a microstrip branch-line hybrid with -15 dB coupling power, composed of two 90$^{\circ}$ and two 270$^{\circ}$ transmission-line sections, is fabricated on a substrate of ${\varepsilon}_r$= 3.4 and h=0.76 mm and measured. In this case, 276.7 ${\Omega}$ characteristic impedance is fabricated using the suggested high impedance transmission-line sections. The measured coupling power is -14.5 dB, isolation and matching is almost perfect at a design center frequency of 2 GHz, showing good agreement with the prediction.

• 한국전자파학회논문지
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• 제18권8호
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• pp.895-903
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• 2007

임의의 종단 임피던스를 갖는 DC block을 정합하기 위한 새로운 설계식이 소개되었으며, 이 설계식을 이용한 microstrip DC block이 제작, 측정되었다. 기존의 DC block은 완전히 정합기지 않았기 때문에, 한 단자에서 여기 된 power가 다른 단자로 모두 전달되지 않는 문제점이 있었다, 이런 문제점을 해결하기 위하여, 한 단자의 등가 공진기 회로를 제시하였으며, 이 등가회로를 이용하여, coupling coefficient에 관계없이, 어느 경우에도 완전 정합을 이룰 수 있는 설계식을 유도했다. 이 설계식을 이용하여 측정된 microstrip DC block의 삽입, 반사 손실은 중심 주파수 4.1 GHz에서 0.82dB, -31dB를 보였으며, 이 측정 결과는 예상된 결과와 잘 일치함을 보여주고 있다.

• 한국의류학회지
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• 제30권9_10호
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• pp.1476-1484
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• 2006

This study is on the esthetic characteristics of Tuxedo-Look in the modern women fashion from 1990s to the present. It could contribute to understand the aspects and the sense of beauty of the modern fashion. This study is performed by reviewing the precedent studies, related literature and deploying fashion portfolios, domestic and international fashion magazines for the exploratory study. The results of the study are the following. First, Tuxedo-Look expresses the androgenous image which weakens the superficial message of masculinity or femininity and produces the unified image of men and women. Tuxedo-Look, a symbolic male dress item, is brought in the women clothes and it is recreated by design modification, new wearing style, and producing effects. Second, Tuxedo-Look emphasizes femininity by using a exposure and body line stressed design and matching the women dress items with various materials and colors or tuxedo. Third, Tuxedo-Look suggests a dismantling point of view such as exaggeration, distortion, secession, and breaking from the convention. Tuxedo-Look expresses uncertain value by breaking up the symbolic valueby coordinating with casual items and denies formal construct of tuxedo such as perfect balance, symmetrical silhouette, formality, totality.

• 한국멀티미디어학회논문지
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• 제14권2호
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• pp.201-209
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• 2011

이 논문은 이미지 매칭 알고리즘의 일종인 수정된 SURF(Speeded Up Robust Feature)와 이미지 블렌딩 알고리즘의 일종인 멀티밴드 블렌딩으로 구성된 파노라마 이미지 스티칭 시스템을 제안한다. 이 논문은 처음에 수정된 SURF를 기술하고 SIFT(Scale Invariant Feature Transform)와 비교하여 SURF를 이 시스템에서 채택한 이유에 대하여 논한다. 그리고 멀티밴드 블렌딩에 대하여 기술하고, 이어서 제안된 파노라마 이미지 스티칭 시스템의 구조에 대하여 설명하고 마지막으로 이미지 질과 처리시간에 대한 평가를 한다. 평가결과는 제안된 시스템이 개별 이미지들을 이음매 없이 연결하였으며, 많은 개개의 이미지 데이터에 대해서도 완전한 파노라마 이미지를 생성하였으며 처리 시간도 SIFT보다 빨랐다.

• 말소리와 음성과학
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• 제5권4호
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• pp.33-41
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• 2013

This study investigated the perceptual and cepstral/spectral characteristics of phonation and their relationships in dysarthria in connected speech. Twenty-two participants were divided into two groups; the eleven dysarthric speakers were paired with matching age and gender healthy control participants. A perceptual evaluation was performed by three speech pathologists using the GRBAS scale to measure the cepstrual/spectral characteristics of phonation between the two groups' connected speech. Correlations showed dysarthric speakers scored significantly worse (with a higher rating) with severities in G (overall dysphonia grade), B (breathiness), and S (strain), while the smoothed prominence of the cepstral peak (CPPs) was significantly lower. The CPPs were significantly correlated with the perceptual ratings, including G, B, and S. The utility of CPPs is supported by its high relationship with perceptually rated dysphonia severity in dysarthric speakers. The receiver operating characteristic (ROC) analysis showed that the threshold of 5.08 dB for the CPPs achieved a good classification for dysarthria, with 63.6% sensitivity and the perfect specificity (100%). Those results indicate the CPPs reliably distinguished between healthy controls and dysarthric speakers. However, the CPP frequency (CPP F0) and low-high spectral ratio (L/H ratio) were not significantly different between the two groups.

• 천문학회보
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• 제43권1호
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• pp.54.4-55
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• 2018

Propagating speeds of coronal mass ejections (CMEs) have been calculated by several geometrical models based on multi-view observations (STEREO/SECCHI and SOHO/LASCO). But in 2015, we were unable to obtain radial velocity of a CME because the STEREO satellites were located near the backside of the sun. As an alternative to resolve this problem, we propose a method to combine a coronal shock front, which appears on the outermost of the CME, and an EUV-wave that occurs on the solar disk. According to recent studies, EUV-wave occurs as a footprint of the coronal shockwave on the lower solar atmosphere. In this study, the shock, observed as a bubble shape, is assumed as a perfect sphere. This assumption makes it possible to determine the height of a coronal shock, by matching the position of an EUV-wave on the solar disk and a coronal shock front in coronagraph. The radial velocity of Halo-CME is calculated from the rate of coronal shock position shift. For an event happened on 2011 February 15, the calculated speed in this method is a little slower than the real velocity but faster than the apparent one. And these results and the efficiency of this approach are discussed.

• 한국전자파학회논문지
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• 제29권2호
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• pp.77-82
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• 2018

테라헤르츠 영역에서 MIM(Metal - Insulator - Metal) 도파관이 주기적으로 배열되어 있는 경우, 도파관 두께의 변화에 따른 전자파의 투과 특성은 널리 연구되지 않았다. 본 논문에서는 금속이 금으로 구성된 주기 구조의 경우 MIM 도파관에 수직으로 입사하는 수평 편파에 의한 전자파의 투과 특성을 다양한 테라헤르츠 주파수 영역에서 확인하고, 그 결과를 분석하고자 한다. 또한 완전 도체의 경우와 비교해 봄으로써 그 차이점을 확인한다.

• 산경연구논집
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• 제10권4호
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• pp.25-31
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• 2019

Purpose - A framework is suggested in this paper which will help crowdfunding platforms to match projects according to expectations of funders, leading to successful campaigns and thus increase the profitability of the crowdfunding platform. Research design, data, and methodology - The paper is theoretical and conceptual in nature which proposes a model for crowdfunding platforms to match expectations of crowds with project fundraisers. Results - Crowdfunding platforms are going through incremental innovations in order to match customer (funders and fundraisers) expectations. Leading crowdfunding platforms like Kickstart holds benchmark for other players in the market but the secret of success lies in matching quality projects with the appropriate funders. Crowdfunding platforms have to securitize the projects and allow only quality projects but also provide a wide range of options for funders. Thus, to manage this trade-off between quality and quantity of options, a framework is proposed. Conclusions - Crowdfunding platforms have to adopt a model which will help them in providing a perfect match between crowds and fundraisers. Each member of the crowd and every project will be assigned a category and rating based on the past records. Securitization of projects will help to entertain only demanded projects which will reduce the number of failing campaigns.

• 한국식생활문화학회지
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• 제36권2호
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• pp.158-167
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• 2021

This study evaluated the degree of harmony of food pairing with Korean traditional liquors according to the taste and flavor. In-depth interviews were performed with eight experts from May 7 to 17, 2016, to screen Korean traditional liquor and food. For traditional liquor, Sanseong-makgeolli, Hansansogokju, Damsol, Gamhongro, and Andong Soju were chosen. For foods, pan-fried beef, squid with vinegar dressing, clam soup, honey-filled rice cake, prune, grilled mushroom, Swiss cheese, pistachio, honey, and chocolate cake were chosen. Harmonization of the analytical results Sanseong-makgeolli, between honey and Pan-fried Beef achieved the most harmonious results. Hansansogokju with honey and prune were harmonious. Damsol and Gamhongro, which are distilled liquor and containing added ingredients, were perfect matched with chocolate cake and squid with vinegar dressing. In the degree of harmony between Andong Soju and food, it was confirmed that squid vinegar and Swiss cheese were the most harmonious. Through the results of this study, it was found that the degree of harmony with food was different depending on the characteristics of alcoholic beverages. In addition, it is believed that not only taste and flavor, but also the alcohol content of alcoholic beverages will play an important role in the harmony with food.

• International Journal of Advanced Culture Technology
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• 제11권4호
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• pp.210-215
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• 2023

As a public space providing night commercial services, night market represents the regional culture of a region or city to a certain extent. With the development of material economy and the continuous improvement of spiritual civilization, the modern night market has also begun to show some new changes. is an important strategy for the development and transformation of modern night market to build the brand image of night market and turn the traditional night market into a new "national tide" night market". Based on the regional cultural perspective, this paper takes many night markets in Changzhou, China as the object of study, and aims to summarize the effective ways to construct a new night market image. We are designed the following conclusions. The first is to deploy rational and unique features. The second is to enrich the business style and to perfect matching. The third is to regulate management and promote multiple effects. Therefore, it is expected that a new strategy will be proposed to create a night market brand image from a local cultural perspective.