• Journal of Power Electronics
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• 제11권5호
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• pp.677-687
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• 2011

In this paper a cycloconverter-type high frequency transformer link inverter with a reduced switch count is analyzed and designed. The proposed topology consists of an H-bridge inverter at the transformer's primary side and a cycloconverter with three bidirectional switches at the secondary. All of the switches of the cycloconverter operate in non-resonant zero voltage and zero current switching modes. To overcome a high voltage surge problem resulting from the transformer leakage inductance, phase angle control based on natural commutation is employed. The effectiveness of the proposed inverter is verified by constructing s 750W prototype. Experimentally, the inverter is able to supply a near sinusoidal output voltage with a total harmonic distortion of less than 1%. For comparison, a PSpice simulation of the inverter is also carried out. It was found that the experimental results are in very close agreement with the simulation.

• 한국산림과학회지
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• 제28권1호
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• pp.1-20
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• 1975

소나무 천연집단(天然集團)의 변이(變異)를 연구(硏究)하기 위(爲)해 주왕산(경북), 안면도(충남), 오대산(강원)의 3개 집단(集團)을 선발(選拔)하고 각 집단(集團) 20개체(個體)를 대상으로 하여 외형적(外形的) 특성(特性), 침엽(針葉)의 특성(特性) 및 재질특성(材質特性)에 대한 변이(變異)를 조사(調査)하였다. 그 결과(結果) 다음과 같은 성적(成績)을 얻었다. 1. 외형적(外形的) 특성(特性)중 수간(樹幹)의 통직성(通直性), 가지의 굵기, 분지각(分枝角)등에서 오대산 집단(集團)이 타 집단에 비하서 바람직한 형태(形態)를 가지고 있다. 2. 침엽(針葉)의 거치밀도(鋸齒密度), 기공열수(氣孔列數), 수지도수(樹脂道數) 등의 형질(形質)에서 집단간(集團間) 개체간(個體間)의 차이(差異)를 인정할 수 있다. 3. 수지도지수(樹脂道脂數)(RDI), 하표피층수(下表皮層數), 유관속(維管束)의 접근도(接近度)등의 관찰결과(結果) 조사된 3개 집 단 모두가 순수한 소나무라는 기준에서 약간의 편의偏倚)가 있다. 4. 추재율(秋材率)과 비중(比重)은 집단간(集團間)의 차이(差異)를 인정할 수 있으나 연륜폭(年輪福)과 가도관(假導管)의 길이에서는 그 차이를 인정할 수 없었다. 개체간(個體間)에는 비중(比重)과 가도관(假導管) 길이에서 유의차(有意差)가 인정된다. 5. 추재율(秋材率)은 11~20년에서 최고치(最高値)를 보이고 21~30년 사이에 감소하여 그 후로는 큰 변화가 없었다. 비중(比重)은 연륜증가에 따라 증가하는 경향을 보였으나 안면도 집단(集團)과 오대산 집단(集團)이 21~30년사이에 한번 감소하였고 주왕산 집단(集團)은 조금씩 계속 증가하였다. 가도관(假導管)은 3개 집단(集團) 모두 연륜의 증가에 따라 증가하는 경향을 보인다. 6. 이곳에 취급한 몇 형질(形質)로써 소나무 3개 집단간(集團間)의 차이가 안정될 수 있다.

• 대한소아신경학회지
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• 제26권4호
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• pp.233-239
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• 2018

목적: 바이러스성 위장염은 유소아에서 흔한 질병이다. 바이러스성 위장염은 위장염과 연관된 양성 경련의 형태로서 경련을 일으킬 수 있다. 로타바이러스 백신 개발 후 노로바이러스는 소아에서 더욱 임상적으로 의미를 갖게 되었다. 본 연구에서는 바이러스 감염이 확진된 위장염과 연관된 소아 경련 환자에서, 특히 노로바이러스를 중심으로 후향적으로 임상양상을 분석해 보고자 하였다. 방법: 2014년 7월부터 2016년 6월까지 명지병원을 내원한 소아환자 중 경련 및 위장염으로 입원한 15세 미만의 소아 환자를 대상으로 의무 기록 조회를 통한 후향적 연구를 진행하였다. 결과: 경련 및 위장염으로 입원한 46명의 환자(남아 24명, 여아 22명)을 대상으로 연구하였다. 이 환자들 중 노로바이러스 21건(45.7%), 아데노바이러스 3건(6.5%), 로타바이러스 2건(4.3%), 아스트로바이러스 1건(2.2%)이 검출되었다. 노로바이러스 위장염군의 환자는 비-노로 바이러스성 위장염군에 비해 설사 발생률이 높았다(61.9% vs 28.0%, P<0.05). 노로바이러스 위장염과 연관된 양성 경련은 전신발작 형태를 보였다. 12명의 환자는 뇌전증 지속상태가 나타났으며, 그 중 5명 (23.8%)이 노로바이러스 위장염군에서, 7명 (33.0%)이 비-노로 바이러스 위장염군(P=0.837) 에서 발생하였다. 발작은 12명의 환자 중 8명(66.7%)에서 정맥으로 투여한 benzodiazepines에 의해 효과적으로 종결되었다. 12명의 환자 중 3명(25%)에서 fosphenytoin이나 levetiracetam과 같은 지속성 항 경련제가 필요하였다. 결론: 위장염과 연관된 양성 경련 환자는 원인이 노로바이러스 또는 비-노로바이러스임에 따라 임상양상이 크게 달라지지 않으나, 초기에 적극적인 항경련 치료를 필요로 하는 경우를 드물지 않게 확인할 수 있었다.

• 한국독어학회지:독어학
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• 제2집
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• pp.149-163
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• 2000

Die Negation im Deutschen wird in der Tradition, besonders aus dem syntaktischen Aspekt, in zwei verschiedenen Arten unterschieden: Sondemegation(Wortnegation oder Konstituentennegation) vs. Satznegation. Demzufolge bei der Satznegation bezieht sich das Negationswort auf die gesamte Aussage, d.h. die vom gesamten Satz $ausgedr\"{u}ckten$ Propositionskomplexe und bei der Sondernegation auf Teile des gesamten Satzes. Diese Unterscheidung wird hauptsachlich durch die Stellungsmoglichkeiten von 'nicht' $begr\"{u}ndet$. Sie wird aus kommunikativ orientierten Aspekten problematisiert. Solche $Ans\"{a}tze$ gehen davon aus, $da{\ss}$ die Negation eine Blockierungsoperation bei der Bearbeitung bereits vorhandener Kenntnisse ist. Aus kommunikativ orientierten Aspekten wird nur bei der Satznegation von 'Negierung' gesprochen, und bei der Sondernegation liegt nur eine negierte Teilstruktur vor, die den Chakrakter der Affirmierung des Gesamtsatzes zwar modifiziert, aber nicht aufhebt. Als $vorla\"{u}figes$ Fazit stellt man fest, $da{\ss}$ die Beschreibung der Negation aus kommunikativ-pragmatischen Sichten die Unterscheidung Satznegation/Sondernegation nicht $\"{u}berfl\"{u}ssig$ macht. Um die Negation besser zu ermitteln, werden nicht nur unterschiedliche syntaktische $Stellungsm\"{o}glichkeiten$ von 'nicht' $ber\"{u}cksichtigen$, sondern auch die im Satz verschieden gegebene Intonation und auch kommunikative $Handlungszusammenh\"{a}nge$.

• 동력기계공학회지
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• 제12권3호
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• pp.50-54
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• 2008

Various Sialon ceramics were fabricated by hot-pressing mixtures of $Si_3N_4$ with additive $Y_2O_3$ and $Al_2O_3$. The polished specimen of SiAlON $I{\sim}III$ went on increasing in strength by heat treatment, heat treated non-polished specimen were similar or up to polished specimen in strength. The polished specimen of both SiAlON IV and V showed a very high strength, but were not Increasing of strength by heat treatment. All specimens were fractured on the surface and at the inner flaws. Surface fractures were initiated from the polished surface flaw and corner flaw. Inner fractures were initiated from an internal defect.

• 한국해양공학회지
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• 제25권1호
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• pp.32-38
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• 2011

Galvanized steel has gone through a chemical process to keep it from corroding. The steel gets coated in layers of zinc because rust will not attack this protective metal. For countless outdoor, marine, or industrial applications, galvanized steel is an essential fabrication component. The reduction of the corrosion rate of zinc is an important topic. In the past, a very popular way to reduce the corrosion rate of zinc was to use chemical conversion layers based on $Cr^{+6}$. However, a significant problem that has arisen is that the use of chromium salts is now restricted because of environmental protection legislation. Therefore, it is very important to develop new zinc surface treatments that are environmentally friendly to improve the corrosion resistance of zinc and adhesion with a final organic protective layer. In this study, a Urethane solution (only Urethane 20 wt.%; S-700) and an organic/inorganic solution with Si (Si polysilicate 10 wt.% + Urethane 10 wt.%; LRO-317) are used. Based on the salt spray test of 72 h, S-700 and LRO-317 had a superior effect for the corrosion resistance on EGI and HDGI, respectively.

• 한국해양공학회지
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• 제24권5호
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• pp.67-74
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• 2010

Chromate conversion coating is a coating technique used to passivate aluminum, zinc, cadmium, copper, silver, magnesium, tin, and their alloys to slow corrosion. The process uses various toxic chromium compounds, which may include hexavalent chromium. The industry is developing less toxic alternatives in order to comply with substance restriction legislation, such as RoHS. One alternative is to develop a Cr-free coating solution. In this study, eco-friendly, Cr-free solutions (urethane solution S-700, organic/inorganic solution with Si LRO-317) were used. Test specimens were dried in a drying oven at $190^{\circ}C$ for 3, 5, 7, and 9 minutes. Corrosion resistance was evaluated using a salt spray test for 72 hours. The results show that the optimum corrosion resistance was achieved at $190^{\circ}C$ for five minutes for EGI and three or five minutes for HDGI, respectively. The adhesive properties of the two types of coating solutions were superior regardless of drying time.

• 한국해양공학회지
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• 제24권5호
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• pp.60-66
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• 2010

Zinc has a number of characteristics that make it well suited for use as a coating to protecting iron and steel products from corrosion. Its excellent corrosion resistance in most environments accounts for its successful use as a protective coating on a variety of products and in many exposure conditions. The excellent field performance of zinc coatings results from their ability to form dense, adherent films that corrode at a rate that ranges from 1% to 10% of the corrosion rate of ferrous materials, depending on the environment. Recently, EU RoHS and EU ELV prohibited the use of materials that adversely affect the environment, such as Pb, Hg, Cd, and $Cr^{+6}$. In this study, environmentally-friendly, Cr-free solutions (epoxy solution, acrylic solution, and urethane solution S-700) and organic/inorganic solution with Si; LRO-317) were used to evaluate the corrosion resistance of zinc-coated steel subjected to a saltwater spray for 72 hours. The coating of urethane solution (S-700) was best among the three kinds of solution with heat treatment during five minutes at $190^{\circ}F$. Test specimens with S-700 and LRO-317 coating were heat treated in a drying oven at 170, 180, 190, 200, and $210^{\circ}C$ for five minutes. The results show that the optimum corrosion resistance was $190^{\circ}C$ in EGI and $170^{\circ}C$ in HDGI, respectively.

• 한국독어학회지:독어학
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• 제4집
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• pp.181-203
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• 2001

Die vorliegende Arbeit zielt ab nicht auf die sprachwissenschaftlichen Auseinandersetzungen, sondern auf dem $\"{U}berblick$ der Analysetypen der Werbesprache. Werbung ist als ein Mittel behandelt, womit die kommunikativen Probleme zwischen den Sendern und den $Empf\"{a}ngern\;gel\"{o}st$ werden will. Und die Werbetexter bedienen sich der Sprache als Kommunikationsmittel. Dabei soli die Kommunikation der Werbung sowohl zur Kommunikation als auch der Persuasion und der Manipulation beitragen. Nach Baumgart(1992:28) bildet die Werbung Vorstellungen im $Bewu{\ss}tsein$ der Rezipienten, und entwickelt das spezielle Image eines produktes, ohne das dieses kaum eine Chance $h\"{a}tte$, gekauft zu werden. Wegen dieser starken $Zweckm\"{a}{\ss}igkeit$ der Werbung ist die Werbesprache mit allen $n\"{o}tigen\;K\"{u}nstlichkeiten$ wohl versehen und als eine Art von der Sprachplannung angesehen. Ihre hohe $K\"{u}nstlichkeit$ ist eine der sprachlichen Faktoren der Werbesprache, die Werbesprache von der Alltagssprache unterscheiden $k\"{o}nnen$. Am Anfang der Industrialisierung hat die Sprachwissenschaft geringeres Interesse an die Werbesprache. Mit der Ausweitung der Warenproduktion durdch Industrisierung kommt die Werbung in Aufschwung, und ihre Sprache wird Gegenstand von verschiedenen $F\"{a}chern$ wie der Soziologie und den Wirtschaftswissenschaften $einschlie{\ss}lich$ der Sprachwissenschaft. Erst seit den $f\"{u}nfziger$ Jahren wird die Werbesprache aus sprachwissenschaftlicher Perspektive interessant. Die meisten sprachwissenschaftlichen Untersuchungen $\"{u}ber$ die Werbesprache beziehen sich auf die sprachlichen Formen($Satzl\"{a}nge$, Satzbau, Satzarten), den Wortschatz(Wortbildungen, $Neusch\"{o}pfungen$, Zusammensetzungen, Ableitungen, Wortarten, $Schl\"{u}sselworter,\;Worth\"{a}ufigkeit,\;Fremd\w\"{o}rter$), die Stilmittel oder rhetorische Mittel, textlinguistische Merkmale (Kommunikationsimplikatur, illokutive Bedeutungen), kulturelle und soziologische Merkmale($Kulturabh\"{a}ngigkeit,\;Kulturspezifit\"{a}t,\;Interkulturalit\"{a}t$), die Sprachkritik, und den semiotischen Aspekt.

• 한국독어학회지:독어학
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• 제1집
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• pp.229-245
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• 1999

Mehrere Sprachen insgesamt oder in Ausschnitten miteinander zu vergleichen, hat die Sprachwissenschaft mit je unterschiedlichen Erkenntnisinteressen wenigstens seit dem 17. Jahrhundert unternommen. Bis in diese Zeit reichen die Versuche einer inhaltlichen, d.h. auf die Inhalte sprachlicher Formen bezogene Sprachtypologie zuruck. Im 19. jahrhundert entstand und entwickelte sich die historisch-vergleichende (komparatistische) Sprachwissenschaft mit dem vorrangigen Bestreben, Ursprung, Entwicklungsgeschichte und Verwandtschaftsbeziehungen einzelner Sprachen durch vergleichende Untersuchungen zu rekonstruieren. Die sprachtypologischen $Bem\"{u}hungen\;fr\"{u}herer$ Zeiten haben ihre Forsetzung in der neueren, etwa in den 60er Jahren $verst\"{a}rkt$ einsetzenden Unversalienforschung. In den meiseten $europ\"{a}ischen$ Sprachen gibt es nicht geringe und $auff\"{a}llige$ Lehnwortbestande. Diese $Wortbest\"{a}nde$ beruhen nicht auf $Zuf\"{a}lligkeiten$, sondern sie sind Ergebnisse internationaler Kontakte mit politischen, kulturellen, okonomischen und anderen Voraussetzungen. Diese sprachlichen Gemeinsamkeiten in verschiedenen Sprachen werden mit dem Begriff des Internationalismus $erfa{\ss}t$. Obwohl die $europ\"{a}ischen$ Sprachen sich immer mehr von den gemeinsamen Ursprungssprachen entfernt haben, verraten die $Wortbest\"{a}nde$ der Internationalismen Tendenzen der $Ann\"{a}herungen$ und der Gemeinsarnkeiten, vor allem auf der Ebene des Wortschatzes. Im Ausblick auf $M\"{o}glichkeiten$ der Verwertung von nationalen $Wortsch\ddpt{a}tzen$ kann man so fomulieren: Internatonalismen 1) $k\"{o}nnen$ die Alltags­kommunikation zwischen Menschen verschiedener Herkunftssprachen erleichtern; sie offenbaren, $da\ss$ viele Fremdsprachen gar nicht so fremdartig sind; 2) haben im Hinblick auf den Fremdsprachenerwerb und den Fremdsprachenunterricht multiplizierten Gebrauchwert: Viele Interlexeme $geh\"{o}ren$ zum festen Bestand $europ\"{a}ischer$ Sprachen; 3) geben $Aufschlu\ss\;\"{u}ber$ geschichtliche und kulturelle $Kontaktvorg\"{a}nge$ und Kontaktergebnisse in Europa; 4) $k\"{o}nnen\;als\;Wortsch\"{a}tze\;einer\;m\"{o}glichen\;europ\"{a}ischen$ Integration betrachtet werden'.