• 한국산업융합학회 논문집
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• 제22권3호
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• pp.373-379
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• 2019

Nowadays, the IoT portable electronic devices have become more useful and diverse, so they require various supply voltage levels to operate. This paper presents a DC-DC buck converter with pulse width modulation (PWM) for portable electronic devices. The proposed step-down DC-DC converter consists of passive elements such as capacitors, inductors, and resistors and an integrated chip (IC) for signal control to reduce power consumption and improves ripple voltage with the resolution. The proposed DC-DC converter is simulated and analyzed in PSPICE circuit design platform, and implemented on the prototype PCB board with a Texas Instruments LM5165 IC. The proposed buck converter is showed 92.6% of peak efficiency including a load current range of 4-10 mA, 3.29 mV of the voltage ripple at 5 V output voltage for the supply voltage 12 V. Measured and Simulated power efficiency are made good agreement with each other.

• 패션비즈니스
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• 제28권1호
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• pp.51-67
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• 2024

Recently, as the "Kidult" culture has become the culture of life, the vintage fashion doll market is rapidly emerging. This change, coupled with a tendency to cherish childhood memories among adults, shows a phenomenon that vintage dolls are gaining popularity. This study explored the possibility of creative fashion doll clothing design, aiming to satisfy consumers' more diverse and unique emotional needs and provide new perspectives and inspiration to the doll fashion industry and the fashion doll industry. Therefore, this study attempted to propose a fashion doll costume design using the Y2K fashion style that is currently popular. Based on publications and prior research considerations, the Y2K fashion style could be categorized into four main styles: 'Future Technology', 'The Matrix', 'Millennium Spice Girl', and 'Harajuku'. Based on characteristics of these four styles, this study designed and produced eight stylish doll costumes incorporating the Y2K style under themes of 'Ex Machina', 'Digital Warrior', 'Rebelious Sugar', and 'Harajuku Dopamine'. This can inspire fashion doll costume design and production based on trendy styles. This study can be a useful foundation for presenting more diverse directions for fashion doll costume design.

• 한국식품저장유통학회지
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• 제19권3호
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• pp.376-384
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• 2012

본 연구는 학교급식 식재료의 품질 관리 향상을 위한 기초자료를 마련하기 위해 대구 경북의 영양(교)사 271명을 대상으로 식재료 구매실태를 조사하였다. 전처리 채소의 사용비율은 도라지(88.4%), 마늘(87.8%), 데친 고사리(80.1%), 연근(65.7%), 우엉(63.5%), 실파(63.5%), 토란대(57.6%), 생강(35.1%), 알타리무(30.6%), 데친 취나물(29.2%), 대파(25.8%), 당근(25.5%), 양파(21.4%), 감자(8.9%) 순이었다. HACCP 인증제품 사용비율은 육류(75.9%), 계란류(66.7%), 두부(65.5%), 전처리 수산물(55.1%), 묵(49.9%), 양념류(44.9%), 김치(30.9%), 전처리 채소류(22.7%), 과일류(6.9%) 순이었다. 친환경식재료의 사용비율은 알류(31.0%), 육류(28.7%), 두부류(22.1%), 과일류(17.7%), 전처리 수산물(16.7%), 양념류(11.9%), 전처리 채소류(10.5%), 김치류(6.7%) 순이었다. 수입 식재료의 이용비율은 묵류(29.2%), 전처리 수산물(24.7%), 두부류(20.5%), 양념류(15.9%), 과일류(10.1%), 전처리 채소류(4.8%), 알류(0.7%), 김치류(0.4%) 순이었다. HACCP 인증이 필요하다고 생각하는 품목은 쇠고기와 돼지고기(81.5%), 닭고기(80.1%), 전처리 수산물(78.6%), 냉동만두(73.8%), 두부(71.6%), 깐 알류(70.8%), 어묵(69.4%), 묵(65.7%), 우유(63.1%), 김치(54.6%), 양념류(50.6%), 냉동우동(45.4%), 전처리채소(44.3%), 두채류(29.5%) 순이었다. 학교에 공급되는 전체 식재료의 품질은 상등급의 식재료가 공급되고 있다고 생각하는 학교가 59.0%로 가장 많았고, 식재료 품질 위변조 사실을 확인한 경험이 있는 경우는 전체의 8.1%, 품질인증 위변조를 확인한 품목은 육류가 12건, 농산물 2건, 닭고기와 수산물이 각 1건이었고, 위변조 사실 확인 후 시정을 요구한 것은 6건, 계약을 취소한 경우 1건이었다. 따라서 우수하고 안전한 식재료가 학교급식에 더 많이 공급될 수 있도록 생산 가공업체, 유통업체의 적극적인 협조와 영양(교)사의 철저한 검수와 적극적인 자세가 요구되었다.

• 전기전자학회논문지
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• 제12권3호
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• pp.167-171
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• 2008

저항형 센서 브리지를 인터페이싱 하기 위한 저항 편차-주파수 변환기를 제시하였다. 이 변환기는 선형 연산 트랜스컨덕턴스 증폭기(linear operational transconductance amplifier: LOTA)와 전류-제어 발진기(current-controlled oscillator: CCO)로 구성된다. 제시된 변환기를 상업용 개별 소자들을 이용하여 SPICE 시뮬레이션 하였다. 시뮬레이션 결과는, 변환기가 16.90 kHz/${\Omega}$의 변환 감도와 ${\pm}$0.03 %의 최대 선형 오차를 가진다는 것을 보여준다.

• 한국자원식물학회지
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• 제25권6호
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• pp.707-718
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• 2012

This study was carried out in order to catalogue the folk plants of 7 counties and cities of northern region of Chungcheongbuk-do from March to October, 2011. Based on the 626 survey sheets collected from 67 residents at 17 places of 7 counties and were subsequently analysed. The identified folk plants in the northern region of Chungcheongbuk-do consisted of a total 348 taxa; 98 families, 250 genera, 298 species, 5 subspecies, 38 varieties, and 7 forms. The use by its usage were: 223 taxa; edible, 123 taxa; medicinal, 4 taxa; dye, 2 taxa; aroma, 6 taxa; spice, 32 taxa; ornamental, 11 taxa; oil, 4 taxa; starch, 22 taxa; and others, respectively, so the edible use is the highest. The most useful part was the leaf, followed by fruit and root. The consistency comparison between the scientific and the local name were the highest in the 50's and the lowest in 80's.

• 대한전자공학회논문지SD
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• 제41권2호
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• pp.67-75
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• 2004

본 논문은 인덕턴스 성분을 포함한 단일 도선 및 트리 구조 RLC 연결선의 버퍼 삽입 방법을 제시한다. 이를 위해 먼저 CMOS 버퍼가 구동하는 단일 RLC 도선에 대한 시간 지연의 대수식을 제시한다. 이 수식은 현재의 서브마이크로미터 공정을 위한 n-th power law 기반에서 유도되었으며, 다양한 RLC 부하를 가지고 실험해 본 결과, 실제 SPICE 시뮬레이션 결과에 비해 최대 9％ 오차를 갖는 것으로 나타났다. 본 논문은 이 지연 시간 수식을 바탕으로 단일 도선 RLC 연결선을 여러 개로 나누는 버퍼 삽입에 관한 수식과 RLC 트리 연결선의 시간 지연을 최적화하기 위해 삽입될 버퍼의 사이즈를 결정하는 알고리듬을 제시한다. 제시된 버퍼 삽입 알고리듬은 0.25㎛ CMOS 공정의 트리 연결선에 적용하였으며, HSPICE 결과를 이용하여 정확도를 검증하였다.

• 한국자원식물학회지
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• 제32권6호
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• pp.669-676
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• 2019

Zanthoxylum piperitum D.C. (ZP) peels has been used as a natural spice and herb medicine for hypertension reduction, for strokes, and for its anti-bacterial and anti-oxidant activity. However, the anti-inflammatory mechanisms employed by ZP have yet to be completely understood. In this study, we elucidate the anti-inflammatory mechanism of ZP in lipopolysaccharide (LPS)-induced RAW264.7 cells. We evaluated the effects of ZP in LPS-induced levels of inflammatory cytokines, prostaglandin E₂ (PGE₂), and caspase-1 using ELISA. The expression levels of inflammatory-related genes, including cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS), were assayed by Western blot analysis. We elucidated the effect of ZP on nuclear factor (NF)-κB activation by means of a luciferase activity assay. The findings of this study demonstrated that ZP inhibited the production of inflammatory cytokine and PGE₂ and inhibited the increased levels of COX-2 and iNOS caused by LPS. Additionally, we showed that the anti-inflammatory effect of ZP arises by suppressing the activation of NF-κB and caspase-1 in LPS- induced RAW264.7 cells. These results provide novel insights into the pharmacological actions of ZP as a potential candidate for development of new drugs to treat inflammatory diseases.

• 센서학회지
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• 제19권1호
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• pp.25-30
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• 2010

This paper presents a low noise CMOS regulator for a low power capacitive sensor interface in a $0.5{\mu}m$ CMOS standard technology. Proposed LDO regulator circuit consist of a voltage reference block, an error amplifier and a new buffer between error amplifier and pass transistor for a good output stability. Conventional source follower buffer structure is simple, but has a narrow output swing and a low S/N ratio. In this paper, we use a 2-stage wide band OTA instead of source follower structure for a buffer. From SPICE simulation results, we got 0.8 % line regulation and 0.18 % load regulation.

• 한국식품조리과학회지
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• 제18권4호
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• pp.455-460
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• 2002

This experiment was conducted to obtain basic information on the natural spice of Elsholtzia splendens, which is one of the native Korean aromatic plants for aromatic, medicinal and ornamental uses. The overall acceptability and the masking effects on the fetid smell of beef were investigated with Elsholtzia splendens-flavored oils by sensory evaluation. The ability of an electronic nose with six metal oxide sensors to classify Elsholtzia splendens flavored oils based on their odors was studied. The response by electronic nose was analyzed by principal component analysis (PCA). In EOI, EOII, and ESI, (이것들이 무엇을 의미하는지 기술할 필요가 있음). overall acceptability of French dressing showed a same level of preference during storage. Fetid smell of beef was not changed by the addition of 4 types of Elsholtzia splendens-flavored oil during storage. In EO I -flavored oil, the proportion of 1st principal component was 0.829, and the proportion of 1st principal component was 0.818 in ESI-flavored oil. The PCA plot was used to detect stored Elsholtzia splendens flavored oils.(앞 뒤 문맥이 안맞음. 뒤에 이어지는 글이 있는지\ulcorner).

• 한국정보과학회논문지:시스템및이론
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• 제29권6호
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• pp.354-360
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• 2002

지연시간 계산은 지연시간을 고려한 배치 단계에서 백만 번 이상도 수행되므로 효과적이면서 간단해야 한다. 본 논문에서는 계산은 매우 빠르고 간단하지만 수 백%의 오차를 가질 수 있는 Elmore delay를 개선하기 위해 Elmore delay와 SPICE 결과의 비율을 보상값으로 이용하는 방법을 제안한다. 제안한 새로운 방법은 resistance shielding effects를 고려하여 실험적으로 지연시간을 보상하여 그 오차를 크게 줄이며, 계산 복잡도는 Elmore delay와 같은 정도로 간단하다. Elmore delay가 31.6 ~ 145.2% 오차를 갖는 RC 트리에 대하여 실험한 결과, 보상된 delay의 오차는 2.5 ~ 22.7%로 크게 줄었다.